10 Central and Peripheral Nervous Systems

Question 1

Intracerebral hemorrhage is often associated with _____

Answer 1

Stroke

Question 2

Hemorrhage in the basal ganglia and thalamus

Answer 2

Ganglionic hemorrhage

Question 3

Ganglionic hemorrhage is commonly caused by

Answer 3

Hypertension

Question 4

Hemorrhage in the lobes of the cerebral hemisphere

Answer 4

Lobar hemorrhage

Question 5

Lobar hemorrhage is commonly caused by

Answer 5

Cerebral amyloid angiopathy

Question 6

Risk factor most commonly associated with deep brain parenchymal hemorrhages

Answer 6

Hypertension

Question 7

Minute aneurysms

Answer 7

Charcot-Bouchard aneurysms

Question 8

Differentiate intracerebral hemorrhage from subarachnoid hermorrahge based on their different etiologies and common locations

Answer 8

Etiology:
I - hypertension, cerebral amyloid anagiopathy; S - saccular aneurysm, traumatic hematoma
Location:
I - basal ganglia and thalamus, cerebral hemisphere; S - subarachnoid space

Question 9

Differentiate Charcot-Bouchard aneurysm from saccular aneurysm

Answer 9

C - vessels less than 300 um (within basal ganglia), associated with chronic HPN
S - larger intracranial vessels in subarachnoid space, intracranial aneurysm

Question 10

State the four types of vascular malformation and differentiate each

Answer 10

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

Question 11

Classified as acute pyogenic meningitis

Answer 11

Suppurative meningitis

Question 12

Histopathology of suppurative meningitis

Answer 12

Intense inflammatory infiltrate
Congestive vessels
Langhans multinucleated cell

Question 13

Most common pattern of tuberculous involvement

Answer 13

Diffuse meningoencephalitis

Question 14

Differentiate suppurative meningitis from TB meningitis

Answer 14

S - acute pyogenic meningitis, CSF: mostly PMNs, elevated protein, dec. glucose
T - chronic bacterial menigoencephalitis, CSF: moderate pleocytosis, high protein, dec/N glucose levels

Question 15

Causative organisms of acute bacterial meningitis with their corresponding age predilection

Answer 15

Neonates - E. coli, Group B strep
Adolescents - N. meningitidis
Adults - S. pneumoniae, L. monocytogenes

Question 16

Enumerate common complications of acute pyogenic menigitis and TB meningitis

Answer 16

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)

Question 17

Enumerate major forms of neurosyphilis

Answer 17

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

Question 18

How do the two lesions compare histologically? (A and T)

Answer 18

A - exudate, meningeal vessels are engorged

T - gelatinous or fibrinous exudate, granulomas

Question 19

Primary brain tumor
Benign tumor of adults
Rounded mass with a well-define dural base that compresses the underlying brain

Answer 19

Meningioma

Question 20

Meningioma arises from

Answer 20

Meningothelial cells of the arachnoid

Question 21

Cytogenic abnormalities in meningioma

Answer 21

Loss of chromosome 22

Question 22

Forms uniform cells that appear in a characteristic whorled appearance

Answer 22

Meningioma

Question 23

Microscopic collections of calcium found in many types of tumor
Circular, acellular, basophilic

Answer 23

Psammoma bodies

Question 24

What are the usual sites of meningioma

Answer 24

Usually attached to the dura, along any external surface of the brain

Question 25

What are the clinical features of this tumor?

Answer 25

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

Question 26

Most common malignant neoplasm of the central nervous system

Answer 26

Medulloblastoma

Question 27

Medullablastoma originates from

Answer 27

Nueroectoderm

Question 28

Medullablastoma is most commonly seen in ___

Answer 28

Cerebellum

Question 29

Molecular alteration in medulloblastoma

Answer 29

Loss of material from 17p with the WNT

Question 30

Medulloblastoma commonly affects

Answer 30

Children, in the midline of cerebellum

Question 31

Tumor tissue contains nodules of differentiated neurocytic cells that express neuronal proteins

Answer 31

Desmplastic nodular medulloblastoma

Question 32

Nodular regions are more abundant and often filled with streaming cells along a fibrillary background

Answer 32

Medulloblastoma with extensive nodularity

Question 33

Characterized by marked nuclear pleomorphism, cell wrapping, high mitotic count, abundant apoptotic bodies

Answer 33

Anaplastic medulloblastoma

Question 34

Individual tumor cells are small with scant cytoplasm and hyperchromatic nuclei that are frequently elongated or crescent shaped

Answer 34

Salt and pepper (MB)

Question 35

List the most common causes of intra-cerebral hemorrhage in the elderly and in infants/newborns

Answer 35

I - intraventricular hemorrhage (IHV) N - hemorrhagic infarction E - hypertension >> intracranial hemorrhage

Question 36

Explain the pathogenesis of pupillary dilatation, vomiting and sensorial changes in increased ICP

Answer 36

Inc ICP >> herniation and impingement - Pupillary dilation (transtentorial herniation) - Vomiting (infratentorial herniation) - Sensorial changes (transtentorial herniation)

Question 37

Sunny-side up or fried egg appearance

Answer 37

Oligodendroglioma

Question 38

Well circumscribed, gelatinous, gray masses, often with cysts, focal hemorrhage and calcification Clear cytoplasm forming a halo

Answer 38

Oligodendroglioma

Question 39

Increased cell density, nuclear anaplasia, mitotic activity and necrosis

Answer 39

Anaplastic oligodendrogliomas

Question 40

Blood vessels within the membrane (oligodendrogliomas)

Answer 40

Chicken-wire appearance

Question 41

Differentiate oligodendroglioma from medullobrlastoma based on their location, age predilection, molecular alterations

Answer 41

``` 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) ```

Question 42

State the overall prognosis (M vs O)

Answer 42

M - 5-year survival rate, 75% | O - 5-10, better prognosis