Neuroradiology Differentials Flashcards
Comprehensive Differentials for Boards
Lesions crossing the corpus callosum
- Glioblastoma multiforme
- Lymphoma
- Progressive multifocal leukoencephalopathy
- Multiple sclerosis
- Mimic: parafalcine meningioma
Ring-enhancing intracranial lesions
- MAGICAL DR mnemonic:
- Metastasis
- Abscess: AIDS, IVDA, immunocompromised state
- Glioblastoma multiforme, high grade glioma
- Infarct
- Contusion/hematoma
- AIDS (toxoplasmosis)
- Lymphoma
- Demyelinating disease
- Radiation necrosis
Posterior fossa mass, child
- Medulloblastoma
- Cerebellar pilocytic astrocytoma
- Ependymoma
- Pontine glioma
Posterior fossa mass, adult
- Metastasis (most common)
- Cerebellar pilocytic astrocytoma
- Hemangioblastoma (von Hippel-Lindau disease
- Medulloblastoma (cerebellar hemisphere)
- Hemorrhage (hypertensive)
Extra-axial mass
- Meningioma
- Arachnoid cyst
- Epidermoid cyst
- Dural metastasis
- Bone lesion with intracranial extension
- Empyema, subdural or epidural
- Sarcoidosis
Cerebellopontine angle mass
• Vestibular schwannoma (bilateral,neurofibromatosis-2) • Meningioma • Arachnoid cyst • Epidermoid cyst (most common) • Other: ependymoma, schwannoma, glomus jugulare
Sellar or suprasellar mass
- GATCH MODE mnemonic:
- Germ cell tumor, Granuloma
- Adenoma, Aneurysm, Arachnoid cyst
- Tuber cinerum hamartoma
- Craniopharyngioma, Rathke’s cleft cyst
- Hypothalamic glioma
- Meningioma, Metastasis
- Optic chiasm glioma
- Dermoid
- Epidermoid
- Lymphoma
Suprasellar mass, adult (common)
- Pituitary adenoma (prolactinoma > GH)
- Craniopharyngioma (30-40 y/o)
- Meningioma
- Chiasmatic/hypothalamic glioma
- Aneurysm
Suprasellar mass, child (common)
- Craniopharyngioma (4-5 y/o)
- Chiasmatic/hypothalamic glioma (NF-1)
- Germinoma
Suprasellar mass, homogeneously enhancing
- Macroadenoma
- Meningioma (planum sphenoidale, clivus)
- Aneurysm
- Germinoma, teratoma
Suprasellar mass, partially calcified
- Meningioma
- Craniopharyngioma
- Aneurysm
- Granuloma
- Dermoid
Suprasellar mass, high attenuation
- Meningioma
- Craniopharyngioma
- Adenoma (hemorrhagic)
- Aneurysm
- Glioma
- Germinoma
Pituitary hemorrhage
adenoma bromocriptine therapy pregnancy XRT anticoagulation LP
Suprasellar mass, Hyperintense T1/T2
- Adenoma (hemorrhagic)
- Craniopharyngioma (cystic, proteinaceous material)
- Rathke’s cleft cyst
Infundibular mass, child
- Germinoma
- Eosinophilic granuloma
- Meningitis
- Lymphoma
- Glioma
- Racemose cysticercosis
Infundibular mass, adult
- Metastasis
- Sarcoid
- Germinoma
- Lymphoma
- Glioma
- Choristoma (granular cell tumor)
Cavernous sinus mass
- Meningioma
- Schwannoma, neurofibroma
- Aneurysm of ICA
- Cavernous sinus thrombosis
- Carotid-cavernous fistula
- Metastasis
- Lymphoma, sarcoid
- Macroadenoma
- Extension from bone tumors: metastasis, chordoma, chondrosarcoma
Cavernous sinus mass, bilateral
- Macroadenoma
- Meningioma
- Lymphoma
- Metastases
CN 5 foramen
Standing Room Only:
V1 - Spinosum
V2 - Rotundum
V3 - Ovale
Pineal region mass
- Pineal cyst (NL <15 mm)
- Germ cell tumor (germinoma)
- Pineoblastoma (rare, child), pineocytoma (rare, adult)
- Metastasis
- Tectal glioma
- Meningioma
- Vein of Galen malformation
Temporal lobe lesion, adult
- GBM, metastasis
- Ganglioglioma (young adult, also parietal lobe/cerebellum), DNET
- HSV
- Trauma
- Mesial temporal sclerosis
Absent posterior pituitary bright spot
- EG
* Diabetes insipidus
Intraventricular mass
- Meningioma (left atrium)
- Metastases, lymphoma
- Ependymoma (4th ventricle)
- Subependymoma (rare, 4th ventricle or frontal horn)
- Choroid plexus papilloma (child, left atrium; rare adult, 4th ventricle)
- Colloid cyst
- Astrocytoma (giant cell astrocytoma in Tuberous Sclerosis)
- Central neurocytoma (rare, adult)
- Medulloblastoma (child, 4th ventricle; adult, cerebellar hemisphere)
- Racemose cysticercosis (mimics epidermoid cyst, arachnoid cyst)
CSF seeding of tumor
- Germinoma
- PNET: medulloblastoma, pineoblastoma, retinoblastoma
- Ependymoma
- Choroid plexus carcinoma
- GBM
- Metastases
Hyperacute blood
24 hours
Oxyhemoglobin
“ It Be”
T1 Iso (I) ………T2 Bright (B)
Acute blood
1-3 days
Deoxyhemoglobin
“ Id Dee”
T1 Iso ………T2 Dark
Early Subacute Blood
3-7 days
Methemoglobin
“BiDee”
T1 Bright ………T2 Dark
Late Subacute Blood
7-14 days
Methemoglobin (Extra cell)
“Baby”
T1 Bright ………T2 Bright
Chronic
> 1 month
Methemoglobin (Extra cell)
“Doo Doo”
T1 Dark ………T2 Dark
White matter disease (multiple)
• Ischemia
• Multiple sclerosis
• Acute disseminated encephalomyelitis: measles, mumps, mononucleosis, varicella; post-vaccination (basal ganglia/thalamus abnormalities differentiate from MS)
• PML (classically occipitoparietal regions)
• Central pontine myelinolysis
• SLE and other collagen vascular diseases
• Sarcoid
• Lyme disease
• Vitamin B12 deficiency
• Radiation injury
• Dysmyelinating disease:
Canavan’s disease (diffuse, macrocephaly)
Krabbe’s disease (diffuse)
Alexander’s disease (anterior)
adrenal leukodystrophy (posterior)
metachromatic leukodystrophy (diffuse)
Pelizaeus-Merzbacher disease (deficient myelin-specific lipids)
Infarct, young adult
- Dissection: post-traumatic, Marfan’s syndrome, FMD, extension of Type A thoracic aortic dissection into common carotid artery
- Drug abuse: cocaine, amphetamine
- Vasculitis: giant cell arteritis, PAN, temporal arteritis; sarcoidosis; SLE, Wegener’s disease, Behcet’s disease; methamphetamine, ergotism
- Basilar meningitis: bacterial, TB, fungal, syphilis
- Fibromuscular dysplasia
- Migraine
- Moyamoya disease (child): idiopathic; mimics include Sickle cell anemia, NF-1, connective tissue disorders (Marfan’s syndrome, Ehlers-Danlos, homocysteinuria), radiation injury, Menke’s kinky hair syndrome, atherosclerosis (uncommon)
Gyriform cortical enhancement
- Stroke
- Cerebritis
- Postictal state
- Hypertensive encephalopathy, eclampsia
- Drugs: cyclosporine, MTX, FK506 (Tacrolimus)
Hypertensive encephalopathy
pregnancy renal failure TTP hemolytic-uremic syndrome similar in appearance to cyclosporine, FK-506 therapy
Dural venous sinus thrombosis
- Infection: otomastoiditis
- Pregnancy
- Dehydration
- Sepsis
- Neoplasm: falx meningioma
- Hypercoagulable states
Conditions associated with cerebral aneurysms
- AVM
- ADPCKD
- Fibromuscular dysplasia
- NF-1
- Collagen vascular disease
- Marfan’s syndrome
- Coarctation of the Aorta
Aneurysm in unusual location
- Mycotic: bacterial endocarditis
- Vasculitis: PAN, SLE, Wegener’s granulomatosis, Takayasu’s disease
- AVM
- Post-traumatic
Hemorrhage, intraxial
- Trauma
- Hypertension (putamen, thalamus, pons, cerebellum)
- Aneurysm (multiple in 15%)
- AVM, cryptic vascular malformation (cavernous hemangioma, capillary telangiectasia)
- Thromboembolic, venous infarct (temporal lobe from transverse sinus thrombosis, parasagittal subcortical white matter from superior sagittal sinus thrombosis, thalami from straight sinus or vein of Galen thrombosis)
- Hemorrhagic metastasis: melanoma, thyroid carcinoma, choriocarcinoma, adenocarcinoma (breast, lung, renal, colon); GBM, oligodendroglioma
- Amyloid angiopathy
- Drugs abuse: cocaine, amphetamine
- Other: coagulopathy, vasculitis, encephalitis
Hemorrhage spontaneous intra-axial, elderly
- HTN
- Amyloid angiopathy
- Metastasis
Hemorrhage spontaneous intra-axial, young
- AVM
- Aneurysm
- Drug abuse: cocaine, amphetamine
- Neoplasm
Hemorrhage multifocal intra-axial
- Trauma
- Metastases
- Amyloid angiopathy
- Vasculitis
- Venous infarction
- Coagulopathy
Hemorrhage, subarachnoid
- Aneurysm
- Trauma
- AVM
Hemorrhage, epidural/subdural
- Trauma
* Coagulopathy
Leptomeningeal enhancement
- Metastases: lung, breast, melanoma, lymphoma/leukemia, PNETs (child)
- Meningitis: TB, fungal; otomastoiditis
- Post-surgical
- SAH
- Meningeal (pial) angiomatosis in Sturge-Weber
Meningitis bugs
- Group B streptococcus (newborn)
- H. infuenzae (child)
- N. meningititis (adolescent)
- S. pneumonia (adult)
Dural enhancement/mass
- Post-craniotomy or LP, CSF diversion
- Neoplasm: meningioma, metastases (breast, prostate, lymphoma), direct extension of primary intracranial tumor, neuroblastoma (child)
- Meningitis
- Post-hemorrhagic: remote SDH, EDH
- Spontaneous intracranial hypotension (CSF leak from lumbosacral root sleeve cyst)
- Sarcoidosis
Ependymal enhancement
- Neoplasm: lymphoma, glioma, CSF spread of primary intracranial tumor or metastasis
- Ventriculitis: meningitis, post-shunting; CMV (AIDS)
Parenchymal calcifications, neonate
- CMV
- Toxoplasmosis
- Rubella infection
- Herpes Simplex infection
- HIV (basal ganglia)
- STARCH mnemonic: Syphilis, Toxoplasmosis, AIDS, Rubella, CMV, Herpes simplex virus-2
T1 hyperintensity
- Intracellular/extracellular methemoglobin
- Fat
- Proteinaceous fluid
- Melanin
- Slow blood flow on certain sequences
- Calcification (hydrated)
T2 hypointensity
- Vascular flow voids
- Deoxyhemoglobin (acute bleed), intracellular methemoglobin, ferritin, hemosiderin
- Calcification or ossification
- Proteinaceous fluid
- Densely cellular mass: meningioma, lymphoma, PNET (pineoblastoma, medulloblastoma, neuroblastoma)
- Iron deposition, physiologic (basal ganglia, substantia nigra, red nucleus, dentate nucleus), iron deposition, pathologic
Calvarial button sequestrum
- O ME mnemonic:
- Osteomyelitis
- Metastases
- EG
Solitary lytic defect in skull
- MT HOLE (“empty hole”) mnemonic:
- Metastasis, multiple myeloma
- TB, trauma
- Histiocytosis, hemangioma
- Osteomyelitis
- Leptomeningeal cyst
- Epidermoid
Loss of lamina dura
- CHOMP mnemonic:
- Cushing’s disease
- Hyperparathyroidism
- Osteomalacia, osteoporosis
- Multiple myeloma
- Paget’s disease
Calcifications in brain
- PINEAL mnemonic:
- Physiologic: pineal gland, choroid plexus, basal ganglia
- Infections: Cysticercosis, toxoplasmosis, TB, CMV
- Neoplasm: craniopharyngioma, oligodendroglioma, meningioma, chordoma
- Endocrine: hypervitaminosis D, hypoparathyroidism, hyperparathyroidism, Fahr’s disease
- Arterial: atherosclerosis, aneurysm
- Lipoma, dermoid
Calcified intracranial mass
- Ca++ COME mnemonic:
- Craniopharyngioma
- Astrocytoma, aneurysm
- Choroid plexus papilloma
- Oligodendroglioma
- Meningioma
- Ependymoma (25%)
Basal ganglia calcification
- Idiopathic
- Hypoparathyroidism, hyperparathyroidism
- Fahr’s disease (familial idiopathic cerebral ferrocalcinosis)
- Post-inflammatory, post-anoxia
- AIDS
- Cockayne’s syndrome
Intramedullary lesion
- Neoplasm: ependymoma (adult, conus medullaris/filum, can be cystic or calcified or bloody), astrocytoma (child), hemangioblastoma, metastasis (rare)
- Infarct, ischemia
- Hematoma
- Demyelinating disease: MS
- Transverse myelitis: post-viral, inflammatory, ischemia, MS, ADEM, SLE, XRT
- Cryptic vascular malformation: cavernous hemangioma, capillary telangiectasia
- Syrinx
- Contusion
- Abscess
Syringomyelia
- Trauma (myelomalacia)
- Neoplasm
- Chiari 1 or 2 malformation
- Infarct (myelomalacia)
- Arachnoiditis: meningitis, back surgery
Intradural, extramedullary lesion
- Meningioma (posterolateral)
- Nerve sheath tumor (anterolateral): schwannoma, neurofibroma
- Metastases (drop): germ cell tumors, ependymoma, PNET; adenocarcinoma, melanoma, lymphoma/leukemia
- Dermoid, epidermoid
- Lipoma
- MANDELIN mnemonic: meningioma, metastasis (drop), arachnoiditis, arachnoid cyst, AVM, neurofibroma, dermoid, epidermoid, ependymoma, lipoma, infection (TB, cysticercosis) NL but tortuous nerve roots
Extradural lesion
- Degenerative disease: disc protrusion, osteophyte, synovial cyst
- Metastases to vertebrae: lung, breast, prostate, lymphoma
- Other tumors: myeloma, chordoma, aneurysmal bone cyst, giant cell tumor, lymphoma/leukemia, osteoblastoma, eosinophilic granuloma, schwannoma, neurofibroma, ganglioneuroma, ganglioneuroblastoma, neuroblastoma
- Epidural abscess: discitis, osteomyelitis
- Hematoma
Epidural lesion, child
- Extension of paraspinal or vertebral tumor: neuroblastoma, ganglioneuroblastoma, ganglioneuroma; neurofibroma, schwannoma
- Abscess
- Ewing’s sarcoma
- Lymphoma/leukemia
- Eosinophilic granuloma
- Other vertebral body tumors (above)
Epidural extension over many levels
- Abscess
- Hematoma
- Metastases
- Lymphoma
Destructive midline, skull-base lesion
- Metastases
- Myeloma
- Nasopharyngeal carcinoma
- Chordoma (midline)
- Chondrosarcoma (off midline)
- Meningioma
- Macroadenoma
- Lymphoma
- Esthesioneuroblastoma (cribiform plate)
- Aggressive sinusitis: aspergillus, mucormycosis
- Mucocele, polyposis
Destructive skull-base lesion, frontal
- Esthesioneuroblastoma
- Metastasis
- meningioma
- Sinonasal carcinoma
- Lymphoma
- Rhabdomyosarcoma
- Aggressive sinusitis
- Mucocele, sinonasal polyposis
Destructive skull-base lesion, basisphenoid
- Nasopharyngeal carcinoma
- Chordoma
- Chondrosarcoma
- Metastases, myeloma
- Macroadenoma
- Meningioma
- Aggressive sinusitis: aspergillus, mucormycosis
J-shaped sella
- Cretinism
- Idiopathic
- Hydrocephalus
- Gargoylism
- Achondroplasia
- Optic glioma
- NF-1
Jugular foramen mass
- Glomus jugulare
- Schwannoma
- Metastasis
- Meningioma
- Asymmetrical or thrombosed jugular vein, ectatic carotid artery, carotid pseudoanuerysm
Far lateral disc herniation mimics
- Conjoined nerve root
- Perineural cyst
- Neurofibroma
Tarlov cyst mimics
- Intrasacral meningocele
* Dural ectasia
Arachnoiditis
- Trauma, surgery
- Intrathecal steroids, anesthesia
- Myelogram
- Infection
Globe lesions
- Uveal melanoma (lobular), uveal metastases (plaque-like)
- Choroidal or retinal detachment
- Vitreous hemorrhage
- Pseudotumor
- Retinoblastoma (child)
- Optic disc Drusen, choroidal osteoma (lateral to optic disc)
Optic nerve or nerve sheath enlargement
- Optic glioma (child, NF-1), optic nerve sheath meningioma (adult), lymphoma/leukemia, metastasis
- Pseudotumor
- Optic neuritis
- Sarcoidosis
Rectus muscle enlargement
- Thyroid opthalmopathy (inferior>medial>superior>lateral)
- Pseudotumor
- Myositis: extension from paranasal sinus infection, pseudotumor
- Metastasis, lymphoma, others
- Vascular congestion from mass at orbital apex, carotid-cavernous fistula, cavernous sinus thrombosis, dural AVM
Lacrimal fossa mass
- Viral infection
- Benign neoplasm: dermoid, pleomorphic adenoma
- Malignant neoplasm: adenoid cystic carcinoma, lymphoma, metastases
- Pseudotumor
- Sarcoidosis
- Sjogren’s syndrome
- Wegener’s granulomatosis
Lacrimal fossa mass, bilateral
- Lymphoma
* Sarcoid
Intraconal mass
- Cavernous hemangioma (adult), capillary hemangioma (child), lymphangioma (child)
- Orbital cellulitis, pseudotumor
- Varix, carotid-cavernous fistula
- Lymphoma, rhabdomyosarcoma (child), metastasis (child: neuroblastoma to bone; adult: breast, lung, prostate, melanoma to uvea, rectus muscles, bone)
Extraconal mass
- Metastasis to bony orbit
- Invasion by adjacent primary tumor: paranasal sinus or nasal SCC, sphenoid wing meningioma
- Lacrimal fossa mass
- Subperiosteal abscess or hematoma
Orbital mass, child
- LO VISHON mnemonic:
- Leukemia, lymphoma
- Optic nerve glioma
- Vascular malformation (capillary hemangioma, lymphangioma)
- Inflammation (pre-, post-septal)
- Sarcoma (rhabdomyosarcoma)
- Histiocytosis
- Orbital pseudotumor, osteoma
- Neuroblastoma
Middle ear mass
- Cholesteatoma, cholesterol granuloma, inflammatory debris/granulation tissue
- Vascular: aberrant carotid artery, dehiscent jugular bulb
- Neoplasm: glomus tympanicum (cochlear promontory, ascending pharyngeal artery embolization), glomus jugulare invading middle ear (glomus jugulotympanicum), hemangioma, others
Lesion causing pulsatile tinnitus
- Aberrant carotid artery, high jugular bulb or dehiscent jugular bulb
- Transverse sinus/internal jugular vein thrombosis, high grade carotid stenosis, dural AVF
- Glomus tympanicum, glomus jugulare invading middle ear