Neuro Flashcards
Methods to identify central sulcus?
- pars bracket
- superior frontal sulcus (post end joins pre c sulcus)
- inv omega (motor hand)
- post c sulcus is bifid (85%)
- thin post c gyrus
- intraparietal sulcus intersects post c sulcus
- midline sulcus (70% most prom sulcus reaching midline is central)
Virchow-Robins spaces associated with what pathologies?
- mucopolysaccharidoses (Hunters & Hurlers)
- “gelatinous pseudocysts” in cryptococcal meningitis
- atrophy in advancing age
*most commonly located lower 1/3 basal ganglia, centrum semiovale, midbrain
Cavum velum interpositum
- extension quadrigeminal plate cistern to formen of monro
- above 3rd ventricle and below fornices
Components of jugular foramen?
separated by jugular spine
- Pars nervosa: glossopharyngeal n (CN 9) w its tympanic branch
- Pars vascularis: jugular bulb, vagus n (CN 10), auricular branch and spinal accessory n (CN 11)
Describe the anatomy of the cavernous sinus
CN3, 4, V1, V2, 6 & carotid run through it
CN2 & V3 adjacent
*CN6 runs next to carotid (rest along wall) hence LR palsy earlier with cav sinus pathologies
Internal auditory canal
7up COKE down (CN7 sup to CN8 (cochlear n component)
Superior & inferior vestibular branch
Skull base foramen contents
Foramen Ovale
CN V3, and Accessory Meningeal Artery
Foramen Rotundum
CN V2 (“R2V2”)
Superior Orbital Fissure
CN 3, CN 4, CNVl, CN6
Inferior Orbital Fissure
CNV2
Foramen Spinosum
Middle Meningeal Artery
Jugular Foramen
Pars Nervosa: CN 9,
Pars Vascularis: CN 10, CN 11
Hypoglossal Canal
CN 12
Optic Canal
CN 2 , and Ophthalmic Artery
Cavernous Sinus
CN 3, CN 4, CN V l, CN V2, CN 6, and the carotid
Internal Auditory Canal
CN 7, CN 8 (Cochlear, Inferior Vestibular and Superior
Vestibular components). “7 Up - Coke Down”
Meckel Cave
Trigeminal Ganglion
Dorello’s Canal
Abducens Nerve (CN 6), Inferior petrosal sinus
Unilateral CN3 aneurysm association?
PCOM aneurysm (can also be basilar apex or junction sup cerebellar/PCA junction aneurysm)
Signs in corpus callosum genesis?
- corpocephaly (asymetric -
- occipital horn dilatation)
steer horn (coronal) - veritcal (race car) wide spaced ventricles
Most common corpus callosum agenesis association?
Intracranial lipoma:
50% interhemispheric fissure
25% quadrigeminal cistern
Iniencepahly
Deficient occipital bone with cervical region defect
Extreme retroflexion of head
Enlarged foramen magnum
‘star gazing’ foetus
Common association of encephalocele?
Chiari III
Encephalocele = NTD where brain and meninges herniate through defect in cranium
Features of rhimbenephalosynapsis
- Absent vermis
- Transversely orientated single lobed cerebellum
- Small 4th ventricle
- Rounded fastigial point with absent primary fissure
Associated with holoprosencephaly spectrum
Associated of Joubert syndrome?
Retinal dysplasia (50%), multicystic dysplastic kidneys (30%), Liver fibrosis (COACH syndrome)
Absent or small vermis.
Molar tooth appearance of the superior cerebellar peduncles (like root of tooth).
Small cerebellum
Absence of pyramidal decussation
Large “batwing” 4th ventricle
Absent fastigial point and primary fissure
3 key findings in Dandy Walker
- Hypoplasia of the vermis (usually inferior part)
- Hypoplastic vermis elevated and rotated
- Dilated, cystic 4th ventricle
Torcula lambdoid inversion
Torcula above level of lamdoid suture, secondary to elevation of tentorium
Often NOT seen in variant Dandy Walker
Presentation and associations of Dandy Walker?
Often obstetric screening
Raised ICP 1st month
Macrocephaly (nearly all within 1st month)
Associations: hydrocephalus (90%), additional CNS malformations (~40% - agenesis CC, encepalocele, heterotopia, polymicrogyria)
Dandy Walker spectrum
- mega cisterna magna - focal enlargement retrocerebellar CSF space
- blake pouch - sac like cystic protrusion through the foramen of magendie into infra/retrocerebellar region
- variant DWM - hypoplastic vermis with dilation of 4th ventricle
- classic DWM - hypoplastic, elevated, rotated vermis with cystic dilation of 4th ventricle
What is holoprosencephaly?
Clevage failure. Spectrum. Abnormal central fusion. Normal cleave back to front. In milder forms normal posterior cortex.
Types of holoprosencephaly?
- Lobar:
Focal areas incomplete fusion anteriorly (usually fornix). Variable mild fusion frontal horns lv.
Normal thalamus.
Absent septum pellucidum, partially absent/normal corpus callosum. - Semi-lobar:
>50% fusion frontal lobes.
Body of LV 1 chamber. Part developed temporal and occipital horns.
Partial or complete thalamic fusion.
Absent septum pellucidum, CC (partial), anterior interhemispheric fissure, anterior falx cerebri.
Cleft lip/palate. - Alobar
No midline cleavage, single midline ventricle.
Fused septum pellucidum, CC, interhemispheric fissure and falx.
Terrible outcome.
Buzzwords for HPE
Cyclops eyes
Cleft lip/palate
Pyriform aperture stenosis (nasal process overgrowth)
Solitary median maxillary incisior (MEGA-incisior)
Arhinencephaly
Minor HPE expression
Midline olfactory bulbs/tracts absent
Can’t smell. Kallmann syndrome (hypogonadism & mental retardation)
Triad of Meckel-Gruber syndrome?
- Occipital encephalocoele
- Multiple renal cysts
- Polydactyly
*strong association with HPE
Constituents of septo optic dysplasia?
“de Morsier syndrome”
- absent septum pellucidum
- hypoplastic optic structures - optic chiasm & optic nerves
- associated with schizencephaly
**azygos ACA assoc. with SOD & lobar HPE
