10 Central and Peripheral Nervous Systems Flashcards
Intracerebral hemorrhage is often associated with _____
Stroke
Hemorrhage in the basal ganglia and thalamus
Ganglionic hemorrhage
Ganglionic hemorrhage is commonly caused by
Hypertension
Hemorrhage in the lobes of the cerebral hemisphere
Lobar hemorrhage
Lobar hemorrhage is commonly caused by
Cerebral amyloid angiopathy
Risk factor most commonly associated with deep brain parenchymal hemorrhages
Hypertension
Minute aneurysms
Charcot-Bouchard aneurysms
Differentiate intracerebral hemorrhage from subarachnoid hermorrahge based on their different etiologies and common locations
Etiology:
I - hypertension, cerebral amyloid anagiopathy; S - saccular aneurysm, traumatic hematoma
Location:
I - basal ganglia and thalamus, cerebral hemisphere; S - subarachnoid space
Differentiate Charcot-Bouchard aneurysm from saccular aneurysm
C - vessels less than 300 um (within basal ganglia), associated with chronic HPN
S - larger intracranial vessels in subarachnoid space, intracranial aneurysm
State the four types of vascular malformation and differentiate each
AVM - enlarged blood vessels separated by gliotic tissue; shunting
Cavernous malformation - low flow channels, cerebellum, pons, subcortical regions
Capillary telangiectasia - foci of dilated, thin-walled vascular channels
Venous angioma - ectatic venous channels
Classified as acute pyogenic meningitis
Suppurative meningitis
Histopathology of suppurative meningitis
Intense inflammatory infiltrate
Congestive vessels
Langhans multinucleated cell
Most common pattern of tuberculous involvement
Diffuse meningoencephalitis
Differentiate suppurative meningitis from TB meningitis
S - acute pyogenic meningitis, CSF: mostly PMNs, elevated protein, dec. glucose
T - chronic bacterial menigoencephalitis, CSF: moderate pleocytosis, high protein, dec/N glucose levels
Causative organisms of acute bacterial meningitis with their corresponding age predilection
Neonates - E. coli, Group B strep
Adolescents - N. meningitidis
Adults - S. pneumoniae, L. monocytogenes
Enumerate common complications of acute pyogenic menigitis and TB meningitis
A - Waterhouse-Friderichsen syndrome (hemorrhagic infarction of the adrenal glands and petechiae); hydrocephalus; chornic adhesive arachnoiditis
T - hydrocephalus (arachnoid fibrosis); arterial occlusion and infarction (obliterative endarteritis)
Enumerate major forms of neurosyphilis
Meningovascular NS (base of the brain and the cerebral convexities) Paretic NS - invasion of T. pallidum Tabes dorsalis - damage to sensory axons in the dorsal roots
How do the two lesions compare histologically? (A and T)
A - exudate, meningeal vessels are engorged
T - gelatinous or fibrinous exudate, granulomas
Primary brain tumor
Benign tumor of adults
Rounded mass with a well-define dural base that compresses the underlying brain
Meningioma
Meningioma arises from
Meningothelial cells of the arachnoid
Cytogenic abnormalities in meningioma
Loss of chromosome 22
Forms uniform cells that appear in a characteristic whorled appearance
Meningioma
Microscopic collections of calcium found in many types of tumor
Circular, acellular, basophilic
Psammoma bodies
What are the usual sites of meningioma
Usually attached to the dura, along any external surface of the brain
What are the clinical features of this tumor?
Slow-growing lesion
Vague nonlocalizing features or focal finding referable to compression of underlying brain
Multiple lesions = NF2 mutations
Express progesterone receptors grow rapidly during pregnancy
Most common malignant neoplasm of the central nervous system
Medulloblastoma
Medullablastoma originates from
Nueroectoderm
Medullablastoma is most commonly seen in ___
Cerebellum
Molecular alteration in medulloblastoma
Loss of material from 17p with the WNT
Medulloblastoma commonly affects
Children, in the midline of cerebellum
Tumor tissue contains nodules of differentiated neurocytic cells that express neuronal proteins
Desmplastic nodular medulloblastoma
Nodular regions are more abundant and often filled with streaming cells along a fibrillary background
Medulloblastoma with extensive nodularity
Characterized by marked nuclear pleomorphism, cell wrapping, high mitotic count, abundant apoptotic bodies
Anaplastic medulloblastoma
Individual tumor cells are small with scant cytoplasm and hyperchromatic nuclei that are frequently elongated or crescent shaped
Salt and pepper (MB)
List the most common causes of intra-cerebral hemorrhage in the elderly and in infants/newborns
I - intraventricular hemorrhage (IHV)
N - hemorrhagic infarction
E - hypertension»_space; intracranial hemorrhage
Explain the pathogenesis of pupillary dilatation, vomiting and sensorial changes in increased ICP
Inc ICP»_space; herniation and impingement
- Pupillary dilation (transtentorial herniation)
- Vomiting (infratentorial herniation)
- Sensorial changes (transtentorial herniation)
Sunny-side up or fried egg appearance
Oligodendroglioma
Well circumscribed, gelatinous, gray masses, often with cysts, focal hemorrhage and calcification
Clear cytoplasm forming a halo
Oligodendroglioma
Increased cell density, nuclear anaplasia, mitotic activity and necrosis
Anaplastic oligodendrogliomas
Blood vessels within the membrane (oligodendrogliomas)
Chicken-wire appearance
Differentiate oligodendroglioma from medullobrlastoma based on their location, age predilection, molecular alterations
Location: O - cerebral hemisphere, M - cerebellum Age: O - 4th and 5th decades, M - children MA: O - isocitrate dehydrogenase, deletions of chromosome 1p and 19q, M - WNT type, SHH type, Group 3 (MYC), Group 4 (i17q)
State the overall prognosis (M vs O)
M - 5-year survival rate, 75%
O - 5-10, better prognosis
