T2 Katz Neuro Test 2

Front 1

What cause lentiform nucleus obscuration and when can it be seen?

Back 1

Cytotoxic edema in basal ganglia. It indicates proximal MCA occlusion-->so limited flow to lenticulostriate arteries.
-Seen as early as 1 hr post stroke onset.

Front 2

What is the most consistent sign of infarction?

Back 2

Diffuse hypodensity & sulcal effacement.

Front 3

What does parenchymal hypodensity in greater than 50% of of MCA indicate?

Back 3

85% mortality rate

Front 4

Wht does hypodensity in greater than 1/3 of MCA indicate?

Back 4

It a contraindication to thrombolytic therapy b/c of high incidence of hemorrhage.

Front 5

What are the findings of a subacute infarction that 1-3 days old on CT?

Back 5

-Increasing mass effect
-Wedge shaped low density
-Hemorrhagic transformation (dry to wet infarct)

Front 6

What are the findings of a subacute infarction in 4-7 days on CT?

Back 6

-Gyral enhancement
-Persistent mass effect

Front 7

What are the findings of a subacute infarction on CT in 1-8 wks?

Back 7

-Mass effect resolves
-Enhancement may persist.

Front 8

What three factors cause enhancement in infarctions?

Back 8

1. breakdown of BBB
2. neovascularity
3. reperfusion of damaged brain tissue

Front 9

What are two types of extra-axial infections?

Back 9

1. Meningitis
2. Subdural & Epidural infections

Front 10

What are the three subtypes of meningitis?

Back 10

1. Acute pyogenic meningitis-->usually bacterial
2. Lymphocytic meningitis-->usually viral, benign, & self-limited.
3. Chronic meningitis-->often in immunocompromised hosts, may be fungal or parasite.

Front 11

Is imaging usually performed for meningitis?

Back 11

-Its not performed to diagnose meningitis b/c imaging can turn out nl even w/ disease, but can be used in those suspected to assess safety of LP.

Front 12

What types of conditions can lead to an abnormal increase of CSF in CNS?

Back 12

cerebral atrophy & focal destructive lesions.

Front 13

Which type of hydrocephalus is most common?

Back 13

Communicating hydrocephalus, aka nonobstructive. Its caused by impaired CSF resorption in absence of any CSF-flow obstruction-->maybe dysfunctional arachnoid granules along superior sagittal sinus.

Front 14

What are three causes of obstructive hydrocephalus?

Back 14

aquuductal stenosis or occlusion, trapped 4th ventricle, ependymitis

Front 15

50% of extra-axial infections are associated w/ what condition?

Back 15

Sinusitis, usually frontal. Occurs by direct extension or septic thrombophlebitis.

Front 16

What usually causes subdural empyemas?

Back 16

meningitis, sinusitis, trauma, or prior surgery.

Front 17

Which condition is an uncommon cause of cerebral infarction but its important b/c of its morbidity? Presents w/ HA & cranial nerve palsies

Back 17

Venous thrombosis

Front 18

What % of AIDS patients get neuro complications?

Back 18

40-60%

Front 19

What are the most frequent causes of CNS complications in AIDS pts?

Back 19

toxoplasmosis (10-33%)
primary CNS lymphoma (2-10%)
PML (10%)

Front 20

What do CNS complications in AIDS pts appear like on CT?

Back 20

hypodense masses w/ nodular or ring enhancement.

Front 21

What 4 things will appear dark on T1 & T2?

Back 21

calcifications, bone, air, slow flowing blood.

Front 22

How do intracranial tumors present?

Back 22

w/ focal neurological deficit, seizure, or HA.

Front 23

Which intr-axial tumor is 50% of all primary CNS neoplasms?

Back 23

Gliomas.

Front 24

Describe the grading system for astrocytomas.

Back 24

-Grade I: benign or low grade
-->lack necrosis & endothelail proliferation

Grade II: same as above.
Grade III: anaplastic
-increased cellularity &
mitosis & pleomorphism
Grade IV: malignant --Glioblastoma --marked necrosis & endothelial proliferation.

Front 25

What is the most aggressive grade of astrocytoma and what is its 2-yr survival rate?

Back 25

Glioblastoma Multiforme, 10-15% survival.

Front 26

Which lesion frequently crosses the corpus callosum?

Back 26

Glioblastoma Multiforme.

Front 27

What is the most common intracranial tumors in adults?

Back 27

Metastasis: 35-50% of intracranial tumors.

Front 28

What is the order of frequency of metastatic brain tumors (high to low)?

Back 28

lung, breast, melanoma, renal, Colon CA.

Front 29

How do CT & MRI correspond to one another in metastatic cancer to the brain?

Back 29

Patient should do contrast enhanced CT & then followup by contrasted MRI.
-20% of pts who demonstrate a single lesion on CT may demonstrate multiple lesions on MRI.

Front 30

Where do half of primary brain tumors in children originate?

Back 30

posterior fossa;

Front 31

What percent of pts w/ medulloblastoma have CSF dissemination at diagnosis?

Back 31

10-30%

Front 32

What is the most common extra-axial neoplasm of the brain & who is most affected?

Back 32

Meningiomas. Middle-aged women.

Front 33

What are the advantages of CT scanning in imaging meningiomas?

Back 33

-can see calcification of meningiomas.
-invasion of surrounding dura frequently provokes an osteoblastic reponse, causing hyperostosis.
-Can show acute tumor hemorrhage & widened vascular grooves in calvarium.

Front 34

Are pituitary adenomas benign or malignant?

Back 34

Almost always benign, w/ no malignant potential.

Front 35

What is the most common demyelination disease & what is the usual age of onset?

Back 35

MS, 3rd-4th decade.

Front 36

What imaging technique should be used for MS?

Back 36

MRI

Front 37

What are typical locations for MS lesions?

Back 37

periventricular white matter, brainstem, cerebellum, spinal cord.

Front 38

What is the most common white matter lesion?

Back 38

Ischemic demyelination, after age 60.