Differentials

Pattern-Based Differentials

Quick differential diagnosis lists with practical imaging clues and common traps.

NeuroRing-enhancing brain lesion›

Differential

  • Metastasis
  • Glioblastoma
  • Abscess
  • Tumefactive demyelination
  • Neurocysticercosis
  • Subacute infarct

Useful clues

  • Restricted diffusion favors abscess but is not exclusive
  • Multiple gray-white junction lesions favor metastases
  • Open ring may suggest demyelination
  • Thick irregular wall favors high-grade tumor

Pitfalls

  • Do not call abscess on ring enhancement alone
  • Always check immune status and diffusion map
NeuroDiffusion restriction in brain›

Differential

  • Acute infarct
  • Abscess
  • Hypercellular tumor
  • Encephalitis
  • Seizure-related change
  • Creutzfeldt-Jakob disease

Useful clues

  • Vascular territory favors infarct
  • Cortical ribbon/basal ganglia may suggest CJD
  • Temporal lobe pattern suggests HSV
  • Mass-like restriction can be lymphoma

Pitfalls

  • T2 shine-through needs ADC confirmation
  • Post-ictal change can mimic infarct
NeuroWhite matter lesions›

Differential

  • Chronic microangiopathy
  • Multiple sclerosis
  • Migraine
  • Vasculitis
  • ADEM
  • Leukodystrophy

Useful clues

  • Dawson fingers/callosal lesions favor MS
  • Deep periventricular punctate lesions common with small vessel disease
  • Symmetric confluent disease suggests metabolic/toxic

Pitfalls

  • Avoid diagnosing MS without dissemination pattern and clinical context
  • Age and vascular risk factors matter
ChestMultiple pulmonary nodules›

Differential

  • Metastases
  • Infection/septic emboli
  • Granulomatous disease
  • Rheumatoid nodules
  • AVMs
  • Sarcoidosis

Useful clues

  • Random peripheral nodules favor hematogenous metastases
  • Cavitation and feeding vessel may suggest septic emboli
  • Perilymphatic pattern suggests sarcoid

Pitfalls

  • Distribution is more useful than number alone
  • Always compare growth
ChestGround-glass opacity›

Differential

  • Infection
  • Edema
  • Hemorrhage
  • Organizing pneumonia
  • NSIP
  • Adenocarcinoma spectrum

Useful clues

  • Smooth septal thickening favors edema
  • Peripheral perilobular pattern favors organizing pneumonia
  • Persistent focal GGO raises adenocarcinoma concern

Pitfalls

  • Poor inspiration can mimic diffuse GGO
  • Do not ignore chronic focal GGO
ChestCavitary lung lesion›

Differential

  • Squamous cell carcinoma
  • TB
  • Bacterial abscess
  • Septic emboli
  • Fungal infection
  • Granulomatosis with polyangiitis

Useful clues

  • Thick irregular wall suggests malignancy
  • Tree-in-bud/upper lobe favors TB
  • Multiple peripheral cavitating nodules suggest septic emboli

Pitfalls

  • Wall thickness is a clue, not a diagnosis
  • Clinical immune status changes priority
AbdomenHypervascular liver lesion›

Differential

  • Hemangioma
  • FNH
  • Adenoma
  • HCC
  • Hypervascular metastasis
  • Arterioportal shunt

Useful clues

  • Peripheral nodular discontinuous enhancement favors hemangioma
  • Central scar favors FNH
  • Washout/capsule in cirrhosis favors HCC

Pitfalls

  • Single arterial phase is often insufficient
  • Background liver disease changes diagnosis
AbdomenCystic pancreatic lesion›

Differential

  • IPMN
  • Serous cystadenoma
  • Mucinous cystic neoplasm
  • Pseudocyst
  • Solid pseudopapillary neoplasm
  • Cystic neuroendocrine tumor

Useful clues

  • Duct communication favors IPMN
  • Microcystic scar favors serous cystadenoma
  • History of pancreatitis favors pseudocyst

Pitfalls

  • Do not assume pseudocyst without pancreatitis history
  • Look for mural nodule and duct dilatation
AbdomenBowel wall thickening›

Differential

  • Infection
  • Inflammatory bowel disease
  • Ischemia
  • Neoplasm
  • Edema/hypoproteinemia
  • Radiation enteritis

Useful clues

  • Long segment symmetric thickening favors benign inflammation
  • Disproportionate fat stranding suggests inflammation
  • Reduced enhancement/pneumatosis raises ischemia

Pitfalls

  • Collapsed bowel can mimic thickening
  • Pattern and length are essential
GUEnhancing renal mass›

Differential

  • Clear cell RCC
  • Papillary RCC
  • Oncocytoma
  • Angiomyolipoma without visible fat
  • Metastasis
  • Lymphoma

Useful clues

  • Macroscopic fat favors AML
  • Hypovascular mass may be papillary RCC
  • Central scar can be oncocytoma but overlaps RCC

Pitfalls

  • Enhancement must be measured
  • Do not rely on scar alone
GUAdnexal cystic mass›

Differential

  • Functional cyst
  • Hemorrhagic cyst
  • Endometrioma
  • Dermoid
  • Cystadenoma
  • Borderline/malignant epithelial tumor

Useful clues

  • T1 bright with shading favors endometrioma
  • Fat-fluid level favors dermoid
  • Solid vascular nodules raise malignancy concern

Pitfalls

  • Use age/menopausal status
  • Simple cyst criteria are modality and size dependent
MSKLytic bone lesion›

Differential

  • Metastasis
  • Myeloma
  • Infection
  • Giant cell tumor
  • Aneurysmal bone cyst
  • Brown tumor

Useful clues

  • Age is key
  • Multiple punched-out lesions suggest myeloma
  • Aggressive periosteal reaction/soft tissue mass raises malignancy

Pitfalls

  • Do not classify without age and location
  • Check matrix and zone of transition
MSKBone marrow edema around joint›

Differential

  • Trauma/stress injury
  • Osteoarthritis
  • Inflammatory arthritis
  • Osteonecrosis
  • Infection
  • Transient osteoporosis

Useful clues

  • Subchondral fracture line favors insufficiency injury
  • Serpiginous margin favors osteonecrosis
  • Effusion/synovitis may guide arthritis/infection

Pitfalls

  • Marrow edema is nonspecific
  • Always inspect cartilage and subchondral bone
Head & NeckCystic neck mass›

Differential

  • Branchial cleft cyst
  • Necrotic nodal metastasis
  • Thyroglossal duct cyst
  • Abscess
  • Lymphatic malformation
  • Ranula

Useful clues

  • Adult lateral cystic neck mass is malignant until proven otherwise
  • Midline tract near hyoid suggests thyroglossal duct cyst
  • Rim enhancement and inflammatory fat suggest abscess

Pitfalls

  • Do not call branchial cyst in older adult without excluding HPV-related nodal metastasis
Head & NeckParotid mass›

Differential

  • Pleomorphic adenoma
  • Warthin tumor
  • Mucoepidermoid carcinoma
  • Metastatic node
  • Lymphoma
  • Inflammatory lesion

Useful clues

  • Tail of parotid and bilateral/multifocal lesions favor Warthin
  • Ill-defined invasive lesion raises malignancy
  • Very T2 bright mass often pleomorphic adenoma

Pitfalls

  • Imaging overlap is high
  • Look for facial nerve/perineural spread
NeuroBasal ganglia T1 hyperintensity›

Differential

  • Manganese deposition
  • Chronic liver disease
  • Hyperglycemia
  • Calcification
  • Hemorrhage
  • Fahr disease

Useful clues

  • Check T2/SWI/CT
  • Symmetry favors metabolic cause
  • Clinical liver disease is key

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroCerebellopontine angle mass›

Differential

  • Vestibular schwannoma
  • Meningioma
  • Epidermoid
  • Arachnoid cyst
  • Metastasis
  • Facial nerve schwannoma

Useful clues

  • IAC extension favors schwannoma
  • DWI bright favors epidermoid
  • Dural tail favors meningioma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroSellar mass›

Differential

  • Pituitary macroadenoma
  • Meningioma
  • Craniopharyngioma
  • Rathke cleft cyst
  • Metastasis
  • Hypophysitis

Useful clues

  • Cavernous sinus invasion
  • Calcification suggests craniopharyngioma
  • Stalk thickening suggests inflammatory/metastatic

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroIntraventricular mass›

Differential

  • Ependymoma
  • Central neurocytoma
  • Subependymoma
  • Choroid plexus tumor
  • Metastasis
  • Colloid cyst

Useful clues

  • Location and age narrow list
  • Foramen of Monro suggests colloid cyst/neurocytoma
  • Calcification common in several lesions

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroLeptomeningeal enhancement›

Differential

  • Infection
  • Carcinomatous meningitis
  • Inflammatory meningitis
  • Neurosarcoidosis
  • Postoperative change
  • Subarachnoid blood

Useful clues

  • Basal cisterns suggest TB/fungal/sarcoid
  • Known malignancy changes priority
  • FLAIR sulcal signal helps

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroPachymeningeal enhancement›

Differential

  • Intracranial hypotension
  • Postoperative change
  • Meningioma en plaque
  • Metastasis
  • IgG4 disease
  • Granulomatous disease

Useful clues

  • Brain sagging favors hypotension
  • Nodular thickening raises neoplasm
  • Look for venous sinus disease

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroCorpus callosum lesion›

Differential

  • Multiple sclerosis
  • Glioblastoma/lymphoma
  • Marchiafava-Bignami
  • Trauma/DAI
  • Infarct
  • Cytotoxic lesion

Useful clues

  • Crossing midline mass suggests high grade tumor/lymphoma
  • Transient splenial lesion can be metabolic/infectious
  • DAI favors trauma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroTemporal lobe signal abnormality›

Differential

  • HSV encephalitis
  • Glioma
  • Autoimmune encephalitis
  • Post-ictal change
  • Mesial temporal sclerosis
  • Infarct

Useful clues

  • Insular/cingulate involvement suggests HSV
  • Hippocampal volume loss favors sclerosis
  • DWI and enhancement pattern help

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroCystic brain lesion›

Differential

  • Arachnoid cyst
  • Porencephalic cyst
  • Neuroglial cyst
  • Cystic tumor
  • Abscess
  • Parasitic cyst

Useful clues

  • CSF signal on all sequences favors benign cyst
  • DWI restriction suggests epidermoid/abscess
  • Enhancing mural nodule suggests tumor

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroSkull base lytic lesion›

Differential

  • Metastasis
  • Myeloma
  • Chordoma
  • Chondrosarcoma
  • Infection
  • Fibrous dysplasia

Useful clues

  • Midline clivus favors chordoma
  • Chondroid matrix off midline favors chondrosarcoma
  • Multiple lesions suggest metastasis/myeloma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestTree-in-bud nodules›

Differential

  • Endobronchial infection
  • TB/NTM
  • Aspiration
  • Cystic fibrosis
  • Diffuse panbronchiolitis
  • Tumor emboli rarely

Useful clues

  • Dependent distribution favors aspiration
  • Upper lobe/cavitation favors TB
  • Bronchiectasis suggests chronic infection

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestCrazy paving›

Differential

  • Pulmonary edema
  • Pneumocystis pneumonia
  • ARDS
  • Pulmonary alveolar proteinosis
  • Hemorrhage
  • Adenocarcinoma

Useful clues

  • Acute setting often edema/infection
  • Chronic geographic pattern suggests PAP
  • Clinical immune status essential

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestMiliary nodules›

Differential

  • Miliary TB
  • Fungal infection
  • Hematogenous metastases
  • Sarcoidosis
  • Pneumoconiosis
  • Hypersensitivity pneumonitis

Useful clues

  • Random tiny nodules suggest hematogenous spread
  • Perilymphatic suggests sarcoid
  • Immune status guides infection

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestMosaic attenuation›

Differential

  • Small airways disease
  • Chronic thromboembolic disease
  • Vascular disease
  • Hypersensitivity pneumonitis
  • Asthma/bronchiolitis
  • Technical expiratory effect

Useful clues

  • Expiratory air trapping favors airway disease
  • Vessel size difference suggests vascular cause
  • CTPA may be needed

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestAnterior mediastinal mass›

Differential

  • Thymoma
  • Lymphoma
  • Germ cell tumor
  • Thyroid goiter
  • Thymic cyst
  • Metastasis

Useful clues

  • Fat/calcification may suggest teratoma
  • Invasive features matter
  • Age and tumor markers help

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestMiddle mediastinal mass›

Differential

  • Lymphadenopathy
  • Foregut duplication cyst
  • Bronchogenic cyst
  • Vascular aneurysm
  • Esophageal lesion
  • Nerve sheath tumor

Useful clues

  • Cyst attenuation and no enhancement favors duplication/bronchogenic cyst
  • Vascular continuity suggests aneurysm
  • Nodes follow lymphatic stations

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestPosterior mediastinal mass›

Differential

  • Neurogenic tumor
  • Extramedullary hematopoiesis
  • Meningocele
  • Esophageal lesion
  • Paravertebral abscess
  • Lymphoma

Useful clues

  • Neural foraminal widening favors nerve sheath tumor
  • Bilateral paravertebral masses suggest EMH
  • Discitis signs suggest abscess

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestPleural thickening›

Differential

  • Empyema
  • Mesothelioma
  • Metastasis
  • Asbestos-related pleural disease
  • Prior infection/hemothorax
  • Fibrothorax

Useful clues

  • Nodular circumferential thickening suggests malignancy
  • Split pleura sign suggests empyema
  • Calcified plaques suggest asbestos exposure

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestBronchiectasis›

Differential

  • Post-infective
  • Cystic fibrosis
  • ABPA
  • Immunodeficiency
  • Aspiration
  • Primary ciliary dyskinesia

Useful clues

  • Upper lobe central pattern suggests CF/ABPA
  • Lower lobe dependent suggests aspiration
  • Situs abnormality suggests ciliary dyskinesia

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenRim-enhancing liver lesion›

Differential

  • Abscess
  • Metastasis
  • Cholangiocarcinoma
  • Necrotic HCC
  • Hemangioma atypical
  • Inflammatory pseudotumor

Useful clues

  • Cluster sign/gas favors abscess
  • Multiple lesions favor metastases
  • Capsular retraction suggests cholangiocarcinoma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenDiffuse hepatic steatosis mimics›

Differential

  • Fatty liver
  • Iron deposition
  • Glycogen storage
  • Chemotherapy effect
  • Hepatitis
  • Perfusion alteration

Useful clues

  • In/out-of-phase MRI confirms fat
  • Iron drops on T2*
  • Vessel course helps pseudolesion

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenSplenic multiple lesions›

Differential

  • Lymphoma
  • Sarcoidosis
  • Fungal microabscesses
  • Metastases
  • Hemangiomas
  • Granulomas

Useful clues

  • Tiny lesions in immunocompromised suggest fungal
  • Bulky nodes suggest lymphoma
  • Calcified lesions often healed granulomas

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenAdrenal mass›

Differential

  • Adenoma
  • Metastasis
  • Pheochromocytoma
  • Myelolipoma
  • Adrenocortical carcinoma
  • Hemorrhage

Useful clues

  • Macroscopic fat suggests myelolipoma
  • Low HU/washout favors adenoma
  • Large irregular heterogeneous lesion concerning

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenPeritoneal nodularity›

Differential

  • Carcinomatosis
  • TB peritonitis
  • Peritoneal mesothelioma
  • Lymphomatosis
  • Endometriosis
  • Splenosis

Useful clues

  • Omental cake suggests carcinomatosis
  • Smooth thickening/necrotic nodes may suggest TB
  • History of splenectomy suggests splenosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenMesenteric mass›

Differential

  • Carcinoid metastasis
  • Lymphoma
  • Desmoid
  • Sclerosing mesenteritis
  • GIST
  • Metastasis

Useful clues

  • Desmoplastic reaction/calcification suggests carcinoid
  • Encasing vessels without obstruction favors lymphoma
  • Prior surgery/FAP suggests desmoid

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenRetroperitoneal fibrosis›

Differential

  • Idiopathic/IgG4
  • Malignancy
  • Radiation
  • Drug-related
  • Infection
  • Erdheim-Chester disease

Useful clues

  • Medial ureteral deviation classic
  • Bulky nodular mass suggests malignancy
  • Periaortic rind suggests fibrosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenGallbladder wall thickening›

Differential

  • Cholecystitis
  • Hepatitis
  • Heart failure
  • Adenomyomatosis
  • Gallbladder carcinoma
  • Hypoalbuminemia

Useful clues

  • Stones/Murphy sign favor cholecystitis
  • Diffuse systemic edema can thicken wall
  • Focal mass-like thickening concerning

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenBiliary duct dilatation›

Differential

  • Choledocholithiasis
  • Pancreatic head cancer
  • Cholangiocarcinoma
  • Benign stricture
  • Sphincter dysfunction
  • Post-cholecystectomy state

Useful clues

  • Abrupt cutoff raises malignancy
  • Intraductal filling defect suggests stone
  • Clinical bilirubin important

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenPancreatic duct dilatation›

Differential

  • Pancreatic cancer
  • Chronic pancreatitis
  • IPMN
  • Ampullary lesion
  • Post-inflammatory stricture
  • Stone

Useful clues

  • Double duct sign raises ampullary/pancreatic lesion
  • Calcifications favor chronic pancreatitis
  • Cyst communication suggests IPMN

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUComplex renal cyst›

Differential

  • Hemorrhagic cyst
  • Infected cyst
  • Cystic RCC
  • Multilocular cystic neoplasm
  • Abscess
  • Bosniak IIF/III lesion

Useful clues

  • Enhancing septa/nodule matters
  • T1 hyperintensity suggests blood/protein
  • Subtraction MRI helps enhancement

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUHydronephrosis without stone›

Differential

  • UPJ obstruction
  • Ureteric stricture
  • Tumor
  • Retroperitoneal fibrosis
  • Pregnancy
  • Reflux

Useful clues

  • Transition point is key
  • Delayed excretion helps functional obstruction
  • Bilateral disease suggests bladder/outlet or retroperitoneal cause

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUBladder wall thickening›

Differential

  • Cystitis
  • Outlet obstruction
  • Neoplasm
  • Radiation cystitis
  • Neurogenic bladder
  • Underdistension

Useful clues

  • Focal enhancing mass suggests tumor
  • Diffuse trabeculation suggests chronic outlet obstruction
  • Poor distension mimics thickening

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUProstate peripheral zone lesion›

Differential

  • Prostate cancer
  • Prostatitis
  • Post-biopsy hemorrhage
  • Granulomatous prostatitis
  • Fibrosis
  • Atrophy

Useful clues

  • Low ADC/high DWI with focal T2 dark lesion concerning
  • Hemorrhage T1 bright
  • Inflammation can mimic cancer

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUTesticular mass›

Differential

  • Seminoma
  • Non-seminomatous germ cell tumor
  • Lymphoma
  • Leydig cell tumor
  • Epidermoid cyst
  • Infarct

Useful clues

  • Older age suggests lymphoma
  • Onion-ring avascular cyst suggests epidermoid
  • Wedge-shaped avascular area suggests infarct

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUEndometrial thickening›

Differential

  • Hyperplasia
  • Polyp
  • Carcinoma
  • Hormonal effect
  • Tamoxifen change
  • Blood products

Useful clues

  • Postmenopausal status changes threshold
  • Focal vascular lesion suggests polyp
  • Myometrial invasion requires MRI staging

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUOvarian solid mass›

Differential

  • Fibroma/fibrothecoma
  • Brenner tumor
  • Metastasis
  • Dysgerminoma
  • Granulosa cell tumor
  • Epithelial malignancy

Useful clues

  • Very low T2 suggests fibrous tumor
  • Bilateral solid masses suggest metastases
  • Ascites/peritoneal disease raises malignancy

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKSclerotic bone lesion›

Differential

  • Bone island
  • Osteoblastic metastasis
  • Osteoid osteoma
  • Paget disease
  • Bone infarct
  • Chronic osteomyelitis

Useful clues

  • Brush border favors bone island
  • Multiple axial lesions suggest metastases
  • Nidus suggests osteoid osteoma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKSoft tissue mass with fat›

Differential

  • Lipoma
  • Atypical lipomatous tumor
  • Liposarcoma
  • Hemangioma
  • Fat necrosis
  • Hibernoma

Useful clues

  • Thick septa/nodular nonfat tissue concerning
  • Phleboliths suggest vascular lesion
  • Deep large lesion needs caution

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKCartilaginous bone lesion›

Differential

  • Enchondroma
  • Low-grade chondrosarcoma
  • Osteochondroma
  • Chondroblastoma
  • Chondromyxoid fibroma
  • Metastasis with chondroid matrix

Useful clues

  • Pain/endosteal scalloping favors chondrosarcoma
  • Epiphyseal lesion in young patient suggests chondroblastoma
  • Ring-and-arc matrix helps

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKPeriosteal reaction›

Differential

  • Trauma/stress fracture
  • Osteomyelitis
  • Osteosarcoma
  • Ewing sarcoma
  • Hypertrophic osteoarthropathy
  • Metastasis

Useful clues

  • Aggressive interrupted pattern concerning
  • Solid smooth reaction often benign/chronic
  • Age and location are key

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKMuscle edema›

Differential

  • Strain/tear
  • Myositis
  • Denervation
  • Infection
  • Rhabdomyolysis
  • Compartment syndrome

Useful clues

  • Feathery edema follows strain
  • Nerve territory suggests denervation
  • Gas/fluid collection suggests infection

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKJoint effusion with synovitis›

Differential

  • Inflammatory arthritis
  • Septic arthritis
  • Crystal arthropathy
  • PVNS/TGCT
  • Hemarthrosis
  • Osteoarthritis flare

Useful clues

  • Blooming suggests hemosiderin/PVNS
  • Bone erosions and fever raise septic concern
  • Crystal disease may calcify

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineIntradural extramedullary mass›

Differential

  • Meningioma
  • Schwannoma
  • Neurofibroma
  • Metastasis
  • Arachnoid cyst
  • Paraganglioma

Useful clues

  • Dural tail favors meningioma
  • Foraminal extension favors nerve sheath tumor
  • Cauda equina lesion may be paraganglioma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineIntramedullary cord lesion›

Differential

  • Ependymoma
  • Astrocytoma
  • Demyelination
  • Hemangioblastoma
  • Metastasis
  • Syrinx

Useful clues

  • Central cord hemorrhagic cap favors ependymoma
  • Long segment inflammatory lesion suggests demyelination
  • Flow voids suggest hemangioblastoma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineVertebral body collapse›

Differential

  • Osteoporotic fracture
  • Metastasis
  • Myeloma
  • Infection
  • Kummell disease
  • Trauma

Useful clues

  • Posterior convexity/soft tissue mass suggests malignancy
  • Fluid cleft suggests Kummell
  • Discitis/endplate destruction suggests infection

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineDiscitis-osteomyelitis mimics›

Differential

  • Infection
  • Modic type 1
  • Inflammatory spondyloarthropathy
  • Neuropathic spine
  • Crystal deposition
  • Postoperative change

Useful clues

  • Disc enhancement/paraspinal abscess favors infection
  • Vacuum disc favors degenerative
  • Clinical markers help

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckSinonasal mass›

Differential

  • Inflammatory polyp
  • Inverted papilloma
  • Squamous carcinoma
  • Esthesioneuroblastoma
  • Fungal disease
  • Lymphoma

Useful clues

  • Cerebriform pattern suggests inverted papilloma
  • Bone destruction raises malignancy
  • Hyperdense allergic fungal mucin is a clue

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckThyroid nodule with suspicious nodes›

Differential

  • Papillary thyroid carcinoma
  • Medullary carcinoma
  • Lymphoma
  • Metastasis
  • Thyroiditis with reactive nodes
  • Anaplastic carcinoma

Useful clues

  • Microcalcifications/cystic nodes favor papillary carcinoma
  • Rapid invasive mass concerning anaplastic
  • Calcitonin context for medullary

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckLaryngeal mass›

Differential

  • Squamous cell carcinoma
  • Papillomatosis
  • Chondrosarcoma
  • Lymphoma
  • Inflammatory granuloma
  • Amyloidosis

Useful clues

  • Cartilage invasion important
  • Submucosal calcified mass may be chondrosarcoma
  • Smoking history matters

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckMasticator space mass›

Differential

  • Odontogenic infection
  • Sarcoma
  • Perineural tumor spread
  • Lymphoma
  • Vascular malformation
  • Benign muscle hypertrophy

Useful clues

  • Dental source and abscess signs common
  • Foramen ovale widening suggests perineural spread
  • Flow voids suggest vascular lesion

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastBreast calcifications›

Differential

  • Benign secretory calcifications
  • DCIS
  • Fibroadenoma involution
  • Fat necrosis
  • Vascular calcification
  • Milk of calcium

Useful clues

  • Fine pleomorphic/linear branching concerning
  • Layering on true lateral suggests milk of calcium
  • Distribution matters

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastArchitectural distortion›

Differential

  • Radial scar
  • Invasive carcinoma
  • Postsurgical scar
  • Sclerosing adenosis
  • Fat necrosis
  • Complex sclerosing lesion

Useful clues

  • No prior surgery raises concern
  • DBT helps confirm true distortion
  • US correlate may guide biopsy

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastCircumscribed breast mass›

Differential

  • Cyst
  • Fibroadenoma
  • Papilloma
  • Phyllodes tumor
  • Mucinous carcinoma
  • Metastasis

Useful clues

  • Anechoic with posterior enhancement is cyst
  • Rapid growth raises phyllodes
  • Older age changes concern

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastAxillary lymphadenopathy›

Differential

  • Reactive node
  • Breast cancer metastasis
  • Lymphoma
  • Melanoma metastasis
  • Granulomatous disease
  • Recent vaccination

Useful clues

  • Cortical thickening/lost hilum concerning
  • Laterality and vaccine history matter
  • Known malignancy changes priority

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricPediatric abdominal mass›

Differential

  • Neuroblastoma
  • Wilms tumor
  • Hydronephrosis
  • Lymphoma
  • Hepatoblastoma
  • Ovarian mass

Useful clues

  • Crossing midline/calcification favors neuroblastoma
  • Renal origin favors Wilms
  • Age is key

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricLimping child hip pain›

Differential

  • Transient synovitis
  • Septic arthritis
  • Perthes disease
  • SCFE
  • Stress injury
  • Osteomyelitis

Useful clues

  • Fever and high markers raise septic arthritis
  • Epiphyseal flattening suggests Perthes
  • Adolescent obese patient suggests SCFE

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricPediatric posterior fossa mass›

Differential

  • Medulloblastoma
  • Pilocytic astrocytoma
  • Ependymoma
  • ATRT
  • Brainstem glioma
  • Metastasis

Useful clues

  • Midline vermian mass favors medulloblastoma
  • Cyst with mural nodule favors pilocytic astrocytoma
  • Fourth ventricle extension favors ependymoma

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricNeonatal bowel obstruction›

Differential

  • Malrotation/volvulus
  • Duodenal atresia
  • Jejunoileal atresia
  • Meconium ileus
  • Hirschsprung disease
  • Anorectal malformation

Useful clues

  • Double bubble suggests duodenal obstruction
  • Microcolon suggests unused colon
  • Urgent volvulus exclusion is key

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
VascularArterial wall thickening›

Differential

  • Atherosclerosis
  • Vasculitis
  • Dissection
  • Intramural hematoma
  • Radiation arteritis
  • Infection/mycotic aneurysm

Useful clues

  • Long smooth inflammatory wall enhancement suggests vasculitis
  • Intimal flap suggests dissection
  • Calcified plaque favors atherosclerosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
VascularVisceral artery aneurysm›

Differential

  • Atherosclerotic aneurysm
  • Pseudoaneurysm pancreatitis/trauma
  • Mycotic aneurysm
  • Fibromuscular dysplasia
  • Vasculitis
  • Segmental arterial mediolysis

Useful clues

  • Pseudoaneurysm enhances like artery
  • Pancreatitis history suggests splenic artery pseudoaneurysm
  • Multiple beaded vessels suggests FMD/SAM

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
VascularDeep venous thrombosis mimics›

Differential

  • Acute DVT
  • Chronic post-thrombotic change
  • Baker cyst rupture
  • Cellulitis
  • Lymphedema
  • Extrinsic compression

Useful clues

  • Noncompressibility confirms DVT
  • Chronic wall thickening/collaterals suggest old clot
  • Calf fluid suggests ruptured cyst

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroHemorrhagic brain lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroCranial nerve enhancement›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroOptic nerve enlargement›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroCavernous sinus lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroPineal region mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestSolitary pulmonary nodule›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestDiffuse cystic lung disease›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestUpper lobe fibrosis›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestLower lobe fibrosis›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
ChestPulmonary artery enlargement›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenAscites with septations›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenGastric wall thickening›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenColonic mass-like thickening›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenLymphadenopathy abdomen›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
AbdomenRenal sinus mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUUrethral stricture›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUSeminal vesicle lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUPlacental mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUCervical mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
GUVaginal cyst›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKAvascular necrosis mimics›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKTendon sheath mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKCalcified soft tissue mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKEpiphyseal lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
MSKDiaphyseal lesion child›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineCauda equina enhancement›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
SpineEpidural collection›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckOrbital apex lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
Head & NeckNasopharyngeal mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastNon-mass enhancement breast MRI›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
BreastBloody nipple discharge imaging›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricPediatric neck mass›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
PediatricPediatric renal cystic lesion›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
VascularPulmonary embolism mimics›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
VascularAortic mural thrombus›

Differential

  • Common benign cause
  • Infection/inflammation
  • Primary neoplasm
  • Metastatic disease
  • Vascular/traumatic cause
  • Post-treatment change

Useful clues

  • Use location, age and enhancement pattern
  • Compare with prior imaging
  • Clinical context changes the top diagnosis

Pitfalls

  • Avoid overcalling from one feature alone
  • Correlate with clinical setting and prior imaging
NeuroRestricted diffusion in spinal cord›

Differential

  • Acute infarct
  • Demyelination
  • Cord contusion
  • Abscess
  • Hypercellular tumor
  • Artifact

Useful clues

  • Vascular territory and abrupt onset favor infarct
  • Enhancement pattern and lesion length help
  • Confirm on ADC

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroNon-enhancing T2 brain mass›

Differential

  • Low-grade glioma
  • Demyelination
  • Cortical dysplasia
  • Subacute infarct
  • Encephalitis
  • Gliosis

Useful clues

  • Mass effect favors tumor
  • Cortical/subcortical expansion is key
  • Follow-up helps when indeterminate

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroCortical calcification›

Differential

  • Sturge-Weber
  • Old infarct
  • Infection
  • Tumor
  • Vascular malformation
  • Metabolic disease

Useful clues

  • Gyriform pattern suggests Sturge-Weber/old infarct
  • CT confirms calcium
  • Enhancement/mass changes concern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroDural-based mass›

Differential

  • Meningioma
  • Dural metastasis
  • Solitary fibrous tumor
  • Lymphoma
  • Granulomatous disease
  • Subdural collection mimic

Useful clues

  • Hyperostosis favors meningioma
  • Bone destruction favors metastasis
  • Flow voids suggest SFT

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestHalo sign›

Differential

  • Angioinvasive fungal infection
  • Hemorrhagic metastasis
  • Vasculitis
  • Septic emboli
  • Organizing pneumonia
  • Adenocarcinoma

Useful clues

  • Immunocompromised patient changes urgency
  • Nodule plus GGO halo can be hemorrhage
  • Look for cavitation evolution

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestReverse halo sign›

Differential

  • Organizing pneumonia
  • Fungal infection
  • Pulmonary infarct
  • TB
  • Sarcoidosis
  • Vasculitis

Useful clues

  • Clinical immune status critical
  • Peripheral wedge shape suggests infarct
  • Nodular rim may suggest granulomatous/infection

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestDiffuse alveolar hemorrhage pattern›

Differential

  • Vasculitis
  • Anticoagulation
  • Pulmonary edema
  • Infection
  • Goodpasture syndrome
  • Drug reaction

Useful clues

  • Rapidly changing GGO/consolidation
  • Clinical hemoptysis may be absent
  • Look for renal/systemic clues

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestUnilateral hyperlucent lung›

Differential

  • Air trapping
  • Pulmonary embolism
  • Swyer-James
  • Technical rotation
  • Mastectomy effect
  • Congenital lobar overinflation

Useful clues

  • Expiratory CT helps air trapping
  • Small vessels suggest vascular/airway cause
  • Check prior surgery

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenIntrahepatic biliary strictures›

Differential

  • PSC
  • Cholangiocarcinoma
  • IgG4 cholangitis
  • Recurrent pyogenic cholangitis
  • Ischemic cholangiopathy
  • AIDS cholangiopathy

Useful clues

  • Multifocal beading suggests PSC
  • Dominant stricture needs caution
  • Pancreatic IgG4 features help

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenLiver iron overload›

Differential

  • Hemochromatosis
  • Transfusional hemosiderosis
  • Chronic liver disease
  • Iron medication
  • Siderotic nodules
  • Technical artifact

Useful clues

  • T2*/R2* quantifies iron
  • Spleen/pancreas pattern helps primary vs secondary
  • Fat can confound

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenHyperdense renal lesion noncontrast›

Differential

  • Hemorrhagic cyst
  • Proteinaceous cyst
  • Papillary RCC
  • Calcified cyst
  • AML with minimal fat
  • Pseudoenhancement issue

Useful clues

  • Enhancement is decisive
  • Homogeneous high attenuation small cyst may be benign
  • Use subtraction MRI if needed

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenFat-containing liver lesion›

Differential

  • HCC with fat
  • Adenoma
  • Angiomyolipoma
  • Lipoma
  • Teratoma rare
  • Focal fat

Useful clues

  • Enhancement and background liver risk matter
  • Macroscopic vs microscopic fat
  • Vessel displacement helps lesion vs focal fat

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUMale infertility imaging abnormality›

Differential

  • Varicocele
  • Obstructive azoospermia
  • Testicular atrophy
  • Epididymal obstruction
  • Congenital absence vas deferens
  • Prior infection

Useful clues

  • Bilateral renal agenesis link with vas deferens anomaly
  • Scrotal Doppler and TRUS may complement
  • Volume comparison matters

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUUterine junctional zone thickening›

Differential

  • Adenomyosis
  • Physiologic contraction
  • Endometrial carcinoma invasion
  • Fibroid distortion
  • Postpartum change
  • Tamoxifen effect

Useful clues

  • T2 bright foci favor adenomyosis
  • Transient contraction changes on repeat
  • Clinical age/context matters

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKBone lesion with fluid-fluid levels›

Differential

  • Aneurysmal bone cyst
  • Telangiectatic osteosarcoma
  • Giant cell tumor with ABC change
  • Chondroblastoma
  • Simple bone cyst fracture
  • Metastasis

Useful clues

  • Fluid levels are nonspecific
  • Solid enhancing component concerning
  • Age/location essential

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKMarrow replacing lesion›

Differential

  • Metastasis
  • Myeloma
  • Lymphoma
  • Leukemia
  • Infection
  • Red marrow reconversion

Useful clues

  • T1 lower than muscle concerning
  • Chemical shift helps red marrow
  • Multiplicity and clinical context key

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
SpineFacet joint edema›

Differential

  • Degenerative facet arthropathy
  • Septic arthritis
  • Inflammatory arthritis
  • Trauma
  • Crystal disease
  • Synovial cyst

Useful clues

  • Paraspinal abscess favors infection
  • Bilateral/sacroiliac disease suggests inflammatory
  • Check epidural extension

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
SpineLeptomeningeal spinal enhancement›

Differential

  • Carcinomatous meningitis
  • Infection
  • Inflammatory arachnoiditis
  • Neurosarcoidosis
  • Postoperative change
  • Blood products

Useful clues

  • Nodular cauda equina enhancement raises malignancy/infection
  • History and CSF important
  • Compare brain imaging

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckOrbital mass adult›

Differential

  • Cavernous venous malformation
  • Lymphoma
  • Metastasis
  • Inflammatory pseudotumor
  • Optic nerve sheath meningioma
  • Lacrimal gland tumor

Useful clues

  • Location within orbit narrows list
  • Molding lesion favors lymphoma
  • Pain favors inflammatory/infectious

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckCavernous sinus enhancement›

Differential

  • Tolosa-Hunt
  • Meningioma
  • Perineural spread
  • Carotid cavernous fistula
  • Thrombosis
  • Metastasis

Useful clues

  • Flow voids/enlarged SOV suggest fistula
  • Foraminal spread suggests perineural tumor
  • Painful ophthalmoplegia can be inflammatory

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastEnhancing breast focus MRI›

Differential

  • Background parenchymal enhancement
  • Papilloma
  • DCIS
  • Invasive carcinoma
  • Fibroadenoma
  • Inflammation

Useful clues

  • Kinetics plus morphology matter
  • New asymmetric focus is more concerning
  • Correlate with mammogram/US

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastPostoperative breast change vs recurrence›

Differential

  • Scar
  • Fat necrosis
  • Seroma
  • Recurrent tumor
  • Radiation change
  • Infection

Useful clues

  • Increasing mass/enhancement concerning
  • Fat signal favors fat necrosis
  • Time from surgery matters

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric mediastinal mass›

Differential

  • Lymphoma
  • Thymus
  • Germ cell tumor
  • Neuroblastoma
  • Foregut duplication cyst
  • Infection

Useful clues

  • Anterior mass with airway compression urgent
  • Posterior mass suggests neurogenic
  • Normal thymus can mimic mass

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric liver mass›

Differential

  • Hepatoblastoma
  • Hemangioma
  • FNH
  • Abscess
  • Mesenchymal hamartoma
  • Metastasis

Useful clues

  • Age and AFP key
  • Vascularity helps hemangioma
  • Cystic multiseptated lesion suggests hamartoma

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
VascularArterial beading›

Differential

  • Fibromuscular dysplasia
  • Vasculitis
  • Segmental arterial mediolysis
  • Atherosclerosis mimic
  • Spasm
  • Connective tissue disorder

Useful clues

  • Renal/cervical arteries common in FMD
  • Aneurysm/dissection suggests SAM
  • Inflammatory markers help vasculitis

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
VascularVenous collateral pathways›

Differential

  • Chronic venous occlusion
  • SVC syndrome
  • Portal hypertension
  • IVC obstruction
  • Congenital venous anomaly
  • Post-thrombotic change

Useful clues

  • Collateral map localizes obstruction
  • Enhancement timing matters
  • Compare central veins

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
CardiacDelayed myocardial enhancement›

Differential

  • Infarct scar
  • Myocarditis
  • Sarcoidosis
  • Amyloidosis
  • Hypertrophic cardiomyopathy
  • Chagas disease

Useful clues

  • Subendocardial vascular pattern favors infarct
  • Mid-wall/subepicardial favors nonischemic
  • Global subendocardial suggests amyloid

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
CardiacPericardial thickening›

Differential

  • Constrictive pericarditis
  • Postoperative change
  • Infection/TB
  • Malignancy
  • Radiation
  • Uremia

Useful clues

  • Septal bounce and ventricular interdependence help
  • Calcification supports chronic constriction
  • Effusive constrictive possible

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
CardiacCardiac mass›

Differential

  • Thrombus
  • Myxoma
  • Metastasis
  • Papillary fibroelastoma
  • Lipoma
  • Sarcoma

Useful clues

  • Location and mobility matter
  • No enhancement favors thrombus
  • Fat signal favors lipoma

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NuclearFocal FDG uptake colon›

Differential

  • Physiologic uptake
  • Polyp/cancer
  • Inflammation
  • Diverticulitis
  • Medication/metformin effect
  • Artifact

Useful clues

  • Focal intense uptake deserves correlation
  • Diffuse bowel uptake may be physiologic/metformin
  • CT correlate changes concern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NuclearBone scan hot lesion›

Differential

  • Metastasis
  • Degenerative change
  • Fracture
  • Infection
  • Paget disease
  • Stress injury

Useful clues

  • Pattern and CT/radiograph correlation key
  • Linear rib uptake often fracture
  • Superscan suggests extensive disease

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NuclearCold thyroid nodule›

Differential

  • Benign nodule
  • Thyroid carcinoma
  • Cyst
  • Thyroiditis focus
  • Adenoma
  • Technical artifact

Useful clues

  • Cold is not diagnostic of malignancy
  • US risk stratification needed
  • Functional context matters

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
InterventionPost-ablation liver margin enhancement›

Differential

  • Expected rim enhancement
  • Residual tumor
  • Hyperemia
  • Abscess
  • Biloma
  • Hemorrhage

Useful clues

  • Nodular arterial enhancement suggests residual
  • Smooth thin rim often expected
  • Diffusion and serial change help

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
InterventionPost-biopsy lung opacity›

Differential

  • Hemorrhage
  • Pneumothorax
  • Atelectasis
  • Air embolism rare
  • Infection delayed
  • Tumor progression

Useful clues

  • Immediate ground-glass around needle path is hemorrhage
  • Monitor pneumothorax
  • Neurologic symptoms after biopsy are urgent

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroBasilar artery occlusion mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroCerebral venous thrombosis mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroDWI-negative stroke›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroBrainstem T2 lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroSubarachnoid FLAIR hyperintensity›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroBilateral thalamic lesions›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroPosterior reversible encephalopathy pattern›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroCerebral microbleeds›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroVentriculomegaly›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
NeuroDiffuse dural calcification›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestCalcified pulmonary nodule›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestAirspace consolidation›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestLobar collapse›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestSolitary cavitary nodule›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestPulmonary cysts›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestSeptal thickening›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestPleural effusion unilateral›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestPneumomediastinum›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestPulmonary artery filling defect›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
ChestChest wall mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenPortal vein thrombosis›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenHepatic vein thrombosis›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenDiffuse pancreatic enlargement›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenSplenic infarcts›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenRenal infarct›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenAdrenal hemorrhage›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenPneumatosis intestinalis›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenFree intraperitoneal air›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenOmental infarction›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
AbdomenAppendiceal mucocele›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUEctopic pregnancy mimics›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUHematosalpinx›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUAdnexal torsion mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUVulvar mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUBladder filling defect›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUUreteric filling defect›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GURenal papillary necrosis›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUMedullary nephrocalcinosis›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUProstatic abscess›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
GUScrotal wall swelling›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKBaker cyst mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKMeniscal cyst›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKACL ganglion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKShoulder labral cyst›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKTarsal coalition›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKPlantar fascia thickening›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKMorton neuroma mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKHand enchondroma›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKSacral insufficiency fracture›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
MSKRib lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckTemporal bone opacification›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckMiddle ear mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckPetrous apex lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckLacrimal gland enlargement›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckSubmandibular swelling›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckRetropharyngeal fluid›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckTongue base mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckSkull vault lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckDental periapical lucency›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
Head & NeckThyroid diffuse enlargement›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastBreast skin thickening›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastRetroareolar mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastIntraductal lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastBreast edema›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastImplant peri-capsular fluid›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastFat-containing breast lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastDeveloping asymmetry›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastGrouped calcifications›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastBreast abscess mimic›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
BreastMale breast mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricNeonatal adrenal mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric renal mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric bone pain›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric airway narrowing›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric abdominal calcification›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric pelvic mass›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric chest hyperinflation›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric skull lesion›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric liver calcification›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available
PediatricPediatric intussusception lead point›

Differential

  • Common benign entity
  • Infection or inflammation
  • Trauma/vascular cause
  • Primary tumor
  • Metastatic/systemic disease
  • Post-treatment or artifact

Useful clues

  • Use age, location and distribution
  • Compare prior imaging
  • Confirm with the best modality for the pattern

Pitfalls

  • Do not diagnose from one imaging sign alone
  • Use clinical context, labs and prior imaging when available