Neuro Flashcards
What’s the relationship between PCOM and CN3 in fetal PCA variant?
PCOM runs superior and and LATERAL to CN3 in fetal PCA, while normally it runs superior and MEDIAL to CN3.
What’s persistent trigeminal artery?
connection between cavernous ICA and basilar. gives the tau sign.
What forms the vein of Galen?
Two internal cerebral veins.
Where does the vein of Galen drain?
Straight sinus.
what’s Kallmann syndrome?
Arhinencephaly (can’t smell). Hypogonadism. Mental Retardation.
Meckel-Gruber Syndrome?
- Occipital encephalocele. - Renal cysts. - Polydactyly. - Strong association with holoprosencephaly.
de Morsier Syndrome?
Septo-optic dysplasia. - absent septum pellucidum. - hypoplastic chiasm. - Associated with schizencephaly. - Azygos anterior cerebral artery can be seen.
what syndrome is associated with Chiari I?
Klipper-Feil syndrome.
Interdigitated cerebral gyri seen in which condition?
Chiari II malformation
what location is more common for shunt obstruction?
Proximal; mostly from ingrowth of choroid and particulate debris.
Findings in methanol toxicity?
- Optic nerve atrophy. - putaminal hemorrhage. - subcortical WM necrosis.
what’s the most common hereditary stroke disorder?
CADASIL. (young pt with migraine and strokes). NOTCH3 mutation in chromosome 19.
which area is first affected by Alzheimer’s?
Hippoocamus, gets atrophied first.
what’s 11C PiB (Pittsburg compound B)?
Amyloid binding tracer; can be used in diagnosing Alzheimer’s.
what’s singulate island sign?
seen in Dementia with Lewy Bodies, in PET there’s sparing of the posterior singulate gyrus.
how can parkisnons be differentiated from MSA by I-123 MIBG?
By looking at the cardiac/mediastinal ratio; abnormal in PD and normal in MSA.
What’s the most common parkinson plus disease?
Progressive Supra-nuclear Palsy. aka Steele-Richardson-Oleszewski.
What’s signs seen in Progressive Supra-nuclear Palsy?
Micky mouse sign: tegmentum atrophy withs paring tectum anf peduncles. Hummingbird sign: midbrain volume loss with concave upper surface and spared pons.
What’s the most common MR findings in Wilson disease?
T1 bright BG.
What’s the correct position for deep brain stimulating leads?
Sub-thalamic nuclei, 9 mm from midline.
How Krabbe disease looks on CT?
Hyperdensities in thalamus, caudat and deep white matter.
What’s the MRS pattern in MELAS?
elevated lactate and low NAA.
Low-grade tumors that typically enhance?
- Ganglioglioma. - Pilocytic astrocytoma.
what kind of mets does neuroblastoma give to the brain🧠 ?
EXTRA-AXIAL METS (to skull, dura, orbit, …).
What’s genetic association with oligodendroglioma?
1p/19q deletion (I was 19 with kevin in Vancouver). pts with this deletion has a better outcome.
zuckerguss seen with which tumor?
Medulloblastoma - “sugar icing” drop mets along the CSF pathway.
What’s Gorlin syndrome?
- Medulloblastoma, - Dural calcs. - Bifid rib. - Basal cell cancer after RXT - Odontogenic keratocysts.
Location difference between SEGA and subependymal nodules?
SEGA is always near the foramin of Monroe; while SEN are along the wall of the venticle. SEGA grows but SEN don’t.
features of xanthogranuloma in MRI?
- Choroid plexus in origin. - Restricts diffusion. - Seen in adults.
CPA mass invading the IAC?
Schwannoma - “following the schwann in the nerve”.
what lab association seen with hemangioblastoma?
Polycythemia
Alanine in MRS?
is associated with Meningioma.
HIV pt with soap and bubbles appearance in MRI?
cryptococcal meningitis. Also from dilated perivascular spaces.
Watershed infarcts in a kid?
Moyamoya
Artery of Percheron
Single trunk from one the PCAs to feed both thalami and rostral midbrain.
What’s the most common systemic vasculitis to involve the CNS?
PAN
What’s the first segment of the ossicles to be eroded by cholesteatoma?
Long process of the incus.
Air in the semicircular canal?
Perilymphatic fistula. Look for cholesteatoma!
Noise-induced vertigo is seen in what condition?
Superior semicircular canal dehiscence. from long standing high ICP.
Large vestibular aqueduct syndrome
- MC cause of congenital SNHL. - Bilateral. - Associated with absence of bony modiolus of choclea.
most common presenting symptom in glomus jugulare?
Hoarseness!
Gardenigo Syndrome
A complication of apical petrositis; - Otomastoiditis - Face pain (CN V neuropathy) - Lateral rectus palsy (CN VI)
Most common location for mucocele?
Frontal sinus.
What’s the relationship between the vein and the nerve inside the parotid gland?
Retromandibular vein runs MEDIAL to the facial nerve.
Which parotid tumor takes up pertechnetate?
Warthins!
Which nerve sheath tumor has target sign on T2?
Neurofibroma (bright rim with decreased central signal).
Grisel’s Syndrome
Torticollis with atlanto-axial joint inflammation or infection.
What’s the most common intra-ocular mass in an adult?
Melanoma. - Can have “collar button shape” - Related to Bruch’s membrane. Can mets to LIVER –> nect to liver imaging.
What’s the most common benign congenital orbital mass in a child?
Dermoid. Classically, superior and lateral from the frontozygomatico suture.
Raccoon eyes
- Metastatic neuroblastoma - Skull base fracture.
Enlarged pituitary gland with T2 dark rim?
Lymphocytic Hypophysitis.
Orbital mass with fluid-fluid levels?
Lymphangioma
“Owl’s eyes” sign in spine MRI
anterior spinal cord infarct.
What’s the imaging findings seen in Guillain Barre Syndrome?
Enhancement of the nerve roots of the Cauda Equina.
Other locations for Pilocytic astrocytoma other than posterior fossa?
- Hypothalamus - Optic chiasm. Association with NF 1 -Cerebellum They are usually solid.
What’s the classic location for ATRT?
pontomesencephalic junction and partly occupies the interpeduncular cistern.
Cortically-based temporal lobe lesion DDx?
P-DOG - Pleomorphic xanthoastrocytoma (PXA). - DNET - Oligodrndtoglioma (might not be temporal). - Ganglioglioma.
What’s the most common neoplasm associated with chronic intractable epilepsy.
Ganglioglioma
Which antibodies have been implicated as a cause for nonneoplastic autoimmune limbic encephalitis?
Anti–glutamic acid decarboxylase (GAD) antibodies
MRI findings in Immune reconstitution inflammatory syndrome (IRIS)?
Presence of enhancement in the PML lesions with worsening of FLAIR hyperintensity upon immune reconstitution is most compatible with IRIS.
Normally enhancing facial nerve segments?
TMG - Tympanic - Mastoid - Geniculate ganglion.
Susac syndrome
microangiopathy consisting of a triad of encephalopathy, branch retinal artery occlusions, and hearing loss. The corpus callosum involvement is characteristically central compared to peripheral, callososeptal involvement seen with MS. - Ophthalmologic evaluation with retinal fluorescein angiography is necessary to demonstrate the peripheral retinal arteriolar branch occlusion.
In a young patient with bilateral optic nerve enhancement and limb weakness, next step?
C-spine MRI, Neuromyelitis optica is strongly suggested.
Under which spectrum Subcortical band heterotopia is classified?
Subcortical band heterotopia (SBH) is classified with lissencephaly complex (agyria–pachygyria) and not with the other heterotopias.
Venous epidural hematomas are commonly associated with injury to what structure?
Dural venous sinus
Telecanthus is seen in which facial fracture?
NOE, due to disruption of the medial canthal ligaments
Which of the following types of mandible fracture poses the greatest risk of inferior alveolar nerve injury?
Angle. Inferior alveolar nerve enters the mandibular canal at the lingula and exits through the mental foramen, which is at the level of second premolar.
Infections and lymphoma in AIDS patients tend to prefer which area?
Basal Ganglia (Crypto, toxo and lymphoma)
protein 14-3-3 in CSF?
CJD
What treatment can be given to MELAS patients who have stroke-like episode?
Urgent administration of nitric oxide precursors (e.g., arginine) in patients with MELAS ameliorates the clinical symptoms associated with stroke-like episodes.
MRI findings in PKAN?
T2-weighted images demonstrate hypointense signal in the globus pallidus with an anteromedial hyperintensity (“eye of the tiger” sign) and in the substantia nigra.
What’s the other name of PKAN?
Hallervorden-Spatz syndrome- disorder of iron accumulation in brain. (eye of the tiger)
Thunderclap headache in a young female?
RCVS. May show Complete resolution of symptoms and imaging findings within 3 months.
What’s the Spetzler-Martin grading system?
Grading AVMs; considers size of the nidus, venous drainage (superficial vs deep) and eloquence of adjacent brain.
What’s “Ivy sign” in moyamoya?
FLAIR and postcontrast T1w sequences can show pial vascular congestion–related hyperintensity, Along subarachnoid spaces
What’s the artery seen coursing in the middl ear in cases of aberrant ICA?
The inferior tympanic artery arising from the ascending pharyngeal artery is consequently hypertrophied and serves as a collateral pathway to supply the horizontal petrous ICA.
Methanol toxicity findings?
PUTAMEN is mainly involved.
What’s (rule of Spence) in neck trauma?
On open mouth view radiographs or coronal CT, sum of lateral displacement of lateral masses of C1 over C2 exceeding 7 mm is considered as a sign of transverse ligament injury
Spinal lesion with hemosiderin cap (T1 bright rim)?
Ependymoma.
Severe hypotension can result in which type of cord infarction?
Central cord infarction
What’s Type 2 caudal regression syndrome.
Low-lying tethered cord with less severe sacral agenesis, typically below S2.
What’s Type 1 caudal regression syndrome.
Abnormal high termination (above L1) of the conus, which is blunted or wedge shaped typically associated with sacral anomalies above S1.
how do metastatic LN from Papillary thyroid cancer usually look like?
Cystic LN with thin walls.
the most common neoplasm of pre-styloid parapharyngeal space.
Pleomorphic adenoma
Where The sphenoid and posterior ethmoid sinuses drain into?
Superior meatus.
Where does the nasolacrimal duct drain?
Inferior meatus
Which bone juvenile nasal angiofibroma can commonly erode?
Medial pterygoid plate
Pregnant or post partum lady with diffusely enlarged pituitary gland?
- Lymphocyitc hypophysitis. - Hemorrhage (sheehan)
The most common pathogen cultured in typical skull base osteomyelitis
Pseudomonas
How chondrosarcoma is different from chordoma?
Off-center location and relatively higher ADC measurements.
Glomus jugulare is supplied by which artery?
Ascending pharyngeal.
What’s Bezold abscess?
is a complication of otitis media with extension of the infection deep to the sternocleidomastoid muscle and throughout the fascial planes of the neck.
Pulsatile red retrotympanic masses ddx.
Glomus tympanic paraganglioma and aberrant ICAs
blue retrotympanic masses ddx
Cholesterol granulomas and dehiscent jugular bulbs
What other vascular anomaly is most commonly associated with an aberrant ICA?
Persistent stapedial artery
Which corresponding bony foramen is absent in persistent stapedial artery?
Foramen spinosum.
Which organ does hereditary hemorrhagic telangiectasia most commonly involve?
Nasal mucosa
Thinning of pars combacta in substantia nigra
Seen in Parkinsons
MRI in vasculitis
MRI is almost 100% sensitive in diagnosing vasculitis, if negative can exclude the diagnosis.
Contraindications for partial laryngectomy, should go straight to total laryngectomy:
- Inter-arytenoid involvement - Cartilage invasion - Sub-glottic extension - Extra-laryngeal invasion.
Salivary gland stones most commonly occur in ?
submandibular gland as the secretions are thicker and viscous.
“mirror-image” type of recurrent intracranial bleeding.
Amyloid angiopathy. Could be lobar, cortical, or sub-cortical bleeding
MS plaques in the spine
usually short segments within the posterior cord.
What causes diffusion restriction in epidermoid?
parallel-layered keratin filaments and flakes
(notch sign) just above the carotid bifurcation
Extension of the branchial cleft cyst between the ICA and ECA is pathognomonic.
Nerve exiting anteriorly from midbrain
oculomotor (III) nerve
the trochlear nerve (IV) comes from the posterior side of the midbrain. It has the longest intracranial length of all the cranial nerves.
Nerves exiting anteriorly from pons
abducent nerves.
What’s the MCC of cerebral vascular malformation?
Developmental venous anomalies. Usually solitary. Associated with cavernomas!.
What’s the most likely cause of a noninfectious masticator space mass.
malignancy, particularly sarcoma.
post-styloid parapharyngeal space
Carotid space
DDX for pulsatile tinnitus?
Aberrant Carotid Artery, Persistent Stapedial Artery, Dehiscent Jugular Bulb, Dural AVF, Paragangliomas, Caroticocavemous “ CC” Fistula.
Möbius syndrome
also known as congenital facial diplegia syndrome, is a rare congenital condition characterized by the absence or underdevelopment of the abducens nerve (CN VI) and facial nerve (CN VII) nuclei.
Difference b/w anencephaly and acrania
the skull is present in anencephaly and absent in acrania. (anencephaly is an insult to the brain after its formed).
Which muscle opens the Eustachian tube?
Tensor veli palitini
What’s s the ONLY muscle that opens the mouth?
Lateral pterygoid. Medial pterygoid and temporalis closes the mouth.
Lateral meningoceles is associated with which disease?
NF-1.
What core volume indicates a poor prognosis in infarcts?
> 70 cc. Named malignant infarct, WON’T do revascuralization.
Meningioma growth starts from
the ARACHNOID space!
Pneumosinus dilatans
Sinuses tend to ENLARGE TOWARDS the meningioma
Meningiomas are primarily supplied by
branches of EXTERNAL CAROTID artery.
Pathologies SPARING the U-fibers
- Post-radiation - Subcortical atherosclerotic encephalopathy (SAE) - metachromatic leukodystrophy - Krabbe - HIV Encephalitis - CADASIL.
Pulsatile exophthalmous
Carotid-cavernous fistula or sphenoid wing dysplasia.
Infundibulum thickening
seen in Langherhans histiocytosis and neurosarcoid.
Metronidazole toxicity typically involves
cerebellar DENTATE NUCLEI bilaterally.
Changes in hypoglycemia SPARE THE THALAMUS.
Changes in hypoglycemia SPARE THE THALAMUS.
Elevated CBV can be seen with aggressive brain tumors.
Elevated CBV can be seen with aggressive brain tumors.
Thick pachymeningeal enhancement ddx
Intracranial hypotension, TB, neurosarcoid, IG-g4 related, Wegners.
acute hyperammonimic encephalopathy.
Diffuse cortical DWI restriction
Fusiform enlargement of nerve roots W/O enhancement
Charcot-Marie-Tooth, if there’s enhancement –> plexiform NF-1.
Post-op perineural fibrosis of the SPINE is a contraindication of doing another spine surgery
because it will create more fibrosis.
Onodi cell
posterior ethmoid cell extends into sphenoid sinus and forms medial wall of the OPTIC CANAL.
Posterior limb of internal capsule is supplied by
Anterior choroidal artery.
where the intradural ICA starts.
Supra-clinoid carotid
most commonly affected nerve in vestibular schannoma.
Superior vestibular nerve
Which sequence is perfusion MRI?
Echo-planar T2*
Subarachnoid FLAIR signal is artifactually increased when
patient is on oxygen or propofol therapy, without abnormal enhancement.
The two primary differential considerations for a ring-enhancing basal ganglial mass in an immunocompromised patient
Lymphoma and toxoplasmosis. CNS lymphoma is thallium avid and toxoplasmosis does not take up thallium.
The pituitary gland is formed from
Rathke’s pouch, which is a superior invagination from the primitive oral cavity.
What’s the second most common suprasellar mass in children?
astrocytoma involving the visual pathway (optic nerve, optic chiasm, and optic tract)
The pineal gland does not have a blood brain barrier.
The pineal gland does not have a blood brain barrier.
The relationship of any pineal region mass to which vein is key for surgical planning and approach.
the internal cerebral veins
Factors that increase AVM bleeding risk
intra-nidal aneurysm, venous ectasia, venous stenosis, deep venous drainage, and posterior fossa location.
The key imaging finding of a hyperacute hematom
peripheral rim of hypointensity on T2-weighted images due to deoxygenation of the most peripheral red cells
Uveoparotid fever
bilateral uveitis, parotid enlargement, and facial nerve palsy, is considered pathognomonic for sarcoidosis.
The contents of the pterygopalatine fossa
pterygopalatine ganglion and branches of the internal maxillary artery.
Bilateral parotid lymphoepithelial cysts
are CLASSIC in HIV.
POSTERIOR Belly of digastric separates which spaces?
Parotic space and Carotid space
Which vein may drape over a colloid cyst make resection more challenging?
Internal cerebral vein
What’s the gender distribution for pineal gland tumors?
- Germ cell tumors: MALES. - Pineoblastoma and pineocytoma: EQUAL in both sexes.
Posterior limb of internal capsule is supplied by what artery?
Anterior choroidal artery.
What’s Supra-tentorial medulloblastoma?
PNET
Recurrent laryngeal nerve supplies ALL laryngeal muscles EXCEPT?
Cricothyroid muscle. Supplied by Superior Laryngeal nerve.
What’s Pelizaeus-Merzbacher disease?
- X-linked leukodystrophy
- Can have tigroid patten when patchy.
- X-linked leukodystrophy
What connects the middle cranial fossa with PPF?
Foramen rotundum
What connects the PPF to the orbital cavity?
Inferior orbital fissure
What’s the continuation of the ACA?
Pericallosal artery; runs along the superior aspect of CC.
