Neurology- Neurophatology (2) Flashcards
Sturge-Weber syndrome (encephalotrigeminal angiomatosis)
- Etiology
Congenital, noninherited (sporadic), developmental anomaly of neural crest derivatives due to somatic mosaicism for an activating mutation in one copy of the GNAQ gene.
Sturge-Weber syndrome (encephalotrigeminal angiomatosis)
- Clinical presentation
STURGE-weber:
Sporadic, port-wine Stain; Tram track calcifications (opposing gyri); Unilateral; Retardation (intellectual disability); Glaucoma, GNAQ gene; Epilepsy
Tuberous sclerosis
- Genetics
TSC1 mutation on chromosome 9 or TSC2 mutation on chromosome 16.
Tuberous sclerosis
- Clinical Manifestations
HAMARTOMAS:
Hamartomas in CNS and skin; Angiofibromas; Mitral regurgitation; Ash-leaf spots; cardiac Rhabdomyoma; (Tuberous sclerosis); autosomal dOminant; Mental retardation (intellectual disability); renal Angiomyolipoma E ; Seizures, Shagreen patches.
Neurofibromatosis type I (von Recklinghausen disease)
- Genetics
- Clinical manifestations
NF1 tumor suppressor gene on chromosome 17. Codes for neurofibromin, a negative regulator of RAS. AD. 100% penetrance.
Café-au-lait spots, cutaneous neurofibromas, optic gliomas, pheochromocytomas, Lisch nodules
Neurofibromatosis type II
- Genetics
- Clinical manifestations
NF2 tumor suppressor gene on chromosome 22. AD.
Bilateral acoustic schwannomas, juvenile cataracts, meningiomas, and ependymomas.
“NF2 affects 2 ears, 2 eyes, and 2 parts of the brain.”
von Hippel-Lindau disease
- Genetics
- Clinical manifestations
Deletion of VHL gene on chromosome 3p. AD
HARP:
- Hemangioblastomas in retina, brain stem, cerebellum, spine;
- Angiomatosis (eg, cavernous hemangiomas in skin, mucosa, organs);
- bilateral Renal cell carcinomas;
- Pheochromocytomas
Glioblastoma multiforme
- Description
- Histology
Malignant 1° brain tumor. In cerebral hemispheres. Can cross corpus callosum (“butterfly glioma”).
Astrocyte origin, GFAP ⊕.
Oligodendroglioma
- Description
- Histology
rare, slow growing. Most often in frontal lobes. “Chicken-wire” capillary pattern.
Oligodendrocyte origin. Often calcified
Meningioma
- Description
- Histology
Common, typically benign. Females > males. Occurs near surfaces of brain and in parasagittal region.
Extra-axial (external to brain parenchyma) and may have a dural attachment (“tail”)
Arachnoid cell origin. Psammoma bodies.
Hemangioblastoma
- Description
- Histology
Most often cerebellar. Associated with von Hippel-Lindau. Can produce erithropoyetin.
Blood vessel origin
Pituitary adenoma
- Description
May be silent or hyperfunctioning. Commonly from lactotrophs; less commonly of GH or ACTH; Rarely TSH, LH, FSH.
*Prolactinoma in women classically presents as galactorrhea, amenorrhea, and decrease bone density due to suppression of estrogen
Schwannoma
- Description
- Histology
Classically at the cerebellopontine angle involving both CNs VII and VIII. Bilateral vestibular schwannomas found in NF-2.
Schwann cell origin, S-100 ⊕. Biphasic
Pilocytic astrocytoma (Childhood)
- Description
- Histology
Low-grade astrocytoma. Most common 1° brain tumor in childhood. Benign, good prognosis. Most often found in posterior fossa.
Glial cell origin, GFAP ⊕. Rosenthal fibers. Cystic + solid (gross).
Medulloblastoma
- Description
- Histology
Most common malignant brain tumor in childhood. Commonly involves cerebellum. Can send “drop
metastases” to spinal cord.
Form of primitive neuroectodermal tumor (PNET). Homer-Wright rosettes, small blue cells
Ependymoma
- Description
- Histology
Most commonly found in 4th ventricl. Can cause hydrocephalus. Poor prognosis.}
Characteristic perivascular pseudorosettes. Rod-shaped blepharoplasts (basal ciliary bodies) found near
the nucleus.
Craniopharyngioma
- Description
- Histology
Most common childhood supratentorial tumor. May be confused with pituitary adenoma.
from remnants of Rathke pouch. Cholesterol crystals found in “motor oil”-like fluid within tumor.
Pinealoma
- Description
- Histology
Can cause Parinaud syndrome; obstructive hydrocephalus; precocious puberty in males (β-hCG production).
Similar to germ cell tumors (seminoma)
Herniation syndromes
- Cingulate (subfalcine) herniation under falx cerebri
Can compress anterior cerebral artery
Herniation syndromes
- Transtentorial (central/downward) herniation
Caudal displacement of brain stem rupture of paramedian basilar artery branches Duret hemorrhages. Usually fatal.
Herniation syndromes
- Uncal herniation
Herniation compresses ipsilateral CN III and contralateral crus cerebri against Kernohan notch (causes contralateral CN III palsy and/or ipsilateral
hemiparesis, ie, a false localizing sign).
Herniation syndromes
- Cerebellar tonsillar herniation into the foramen magnum
Coma and death result when these herniations compress the brain stem
Motor neuron signs
Pag. 513
Spinal muscular atrophy
- Phatophysiology
- Clinical presentation
Congenital degeneration of anterior horns. AR. SMN1 mutation.
LMN lesions only, symmetric weakness. Floppy baby, tongue fasciculations.
*SMA type 1 is called Werdnig-Hoffmann disease.
Amyotrophic lateral sclerosis (Lou Gehrig disease)
- Phatophysiology
- Treatment
Combined UMN and LMN. No sensory or bowel/bladder deficits. Can be caused by defect in superoxide dismutase 1.
Treatment: riluzole.
Complete occlusion of anterior spinal artery
- Phatophysiology
- Clinical presentation
Spares dorsal columns and Lissauer tract. midthoracic
ASA territory is watershed area, as artery of Adamkiewicz supplies ASA below T8.
Presents with UMN deficit below the lesion, LMN deficit at the level of the lesion, and loss of pain and temperature sensation below the lesion.
Tabes dorsalis
- Phatophysiology
- Associations
degeneration of dorsal columns and roots. ⊕ Romberg sign and absent DTRs.
Associated with Charcot joints, shooting pain, Argyll
Robertson pupils.
Syringomyelia
- Phatophysiology
Syrinx expands and damages anterior white commissure of spinothalamic tract bilateral symmetrical loss of pain and temperature sensation in cape-like distribution.
*Seen with Chiari I malformation
Vitamin B12 deficiency
- Clinical manifestations
“subacute combined degeneration SCD”
Spinocerebellar tracts, lateral Corticospinal tracts, and Dorsal columns
Cauda equina syndrome
Compression of spinal roots L2 and below.
Unilateral radicular pain, absent knee and ankle reflex, loss of bladder and anal sphincter control, saddle anesthesia
Poliomyelitis
- Phatophysiology
- Tests
Caused by poliovirus (fecal-oral transmission). causes destruction of cells in anterior horn of spinal cord (LMN death).
CSF shows lymphocytic pleocytosis and slight increase of protein (with no change in CSF glucose). Virus recovered from stool or throat.
Brown-Séquard syndrome (hemisection of spinal cord)
- Clinical manifestations
Ipsilateral loss of all sensation at level of lesion
Ipsilateral LMN signs at level of lesion
Ipsilateral UMN signs below level of lesion
Ipsilateral loss of proprioception, vibration, light touch, and tactile sense below level of lesion.
Contralateral loss of pain, temperature, and crude touch below level of lesion
Friedreich ataxia
- Genetics
- Spinal Tracts affected
Repeat disorder (GAA) on chromosome 9 in gene that encodes frataxin (iron binding protein). AR
Degeneration of lateral corticospinal tract, spinocerebellar tract, dorsal columns, and dorsal root ganglia.
Friedreich ataxia
- Clinical presentation
Staggering gait, frequent falling, nystagmus, dysarthria, pes cavus, hammer toes, diabetes mellitus, hypertrophic cardiomyopathy (cause of death). Presents in childhood with kyphoescoliosis.
Causes of peripheral facial palsy
Bells palsy, Lyme disease, herpes zoster (Ramsay Hunt syndrome), sarcoidosis, tumors (eg, parotid gland), diabetes mellitus.
Common cranial nerve lesions
- CN V motor lesion
- CN X motor lesion
- CN XII motor lesion
Jaw deviates toward side of lesion.
Uvula deviates away from side of lesion
LMN lesion. Tongue deviates toward side of lesion
Common cranial nerve lesions
- CN XI motor lesion
Weakness turning head to contralateral side of lesion. Shoulder droop on side of lesion.
The left SCM contracts to help turn the head to the right.
Cholesteatoma
Overgrowth of desquamated keratin debris within the middle ear space; may erode ossicles, mastoid air cells conductive hearing loss. Often presents with painless otorrhea.
Peripheral vertigo
- Etiology
More common. Inner ear etiology (eg, semicircular canal debris, vestibular nerve infection, Ménière disease, benign paroxysmal positional vertigo [BPPV])
Central vertigo
- Findings
Directional or purely vertical nystagmus, skew deviation, diplopia, dysmetria. Focal neurologic findings.
Meniere disease triad
sensorineural hearing loss, vertigo, tinnitus
