Diagnostic procedures and results

Question 1

What kind of diagnostic procedure is useful for increased intracranial pressures, and delineates ventricals, localizes tumors?

Answer 1

ventriculography

- xrays of skull after injection of air into lateral ventricles

Question 2

What is tomography?

Answer 2

layered xray exposures (horizontal or vertical)

Question 3

What’s the difference between myelography and ventriculography?

Answer 3

ventriculography = xrays of SKULL after injection of air into LATERAL VENTRICALS

myelography = xrays of SPINE after injection of air or dye into SPINAL SUBARACHNOID SPACE

Question 4

Does CT or MRI have radiation?

Answer 4

CT does, MRI does not

• CT is narrow x-ray beams transmitted through tissues of varying densities and precisely measured
• MRI is nuclear particles depicted in a strong external magnetic field

Question 5

What’s the most superior imaging of the brain?

Answer 5

MRI

Question 6

What is the primary diagnostic measure for examination of tumors, demyelination, and vascular abnormalities?

Answer 6

MRI

Question 7

What are contraindications to MRI?

Answer 7

metal implants, pacemakers

Question 8

When is a PET used?

Answer 8

allows for physiological mapping, a major clinical research tool for imaging cerebral blood flow, brain metabolism

Question 9

What tool allows 3D localization with high spatial resolution?

Answer 9

MRI

Question 10

Does a PET have better resolution than CT?

Answer 10

no, CT better, MRI best

Question 11

What diagnostic tool delineates abnormalities impinging on the subarachnoid space?

Answer 11

myelgraphy (xrays of spine after injection of air into spinal subarachnoid space)

Question 12

What diagnostic measurement provides useful information about structural disease of the brain, especially when seizures are present or likely?

Answer 12

EEG (electroencephalography)

Question 13

What tool is useful for imaging the lumen of carotid artery and analyzing flow, detection of plaques in carotid arteries?

Answer 13

ultrasound (echoencphalogram)

• also measures position and shifts of midline structures

Question 14

What level of the spinal cord are spinal punctures done?

Answer 14

below L1-2

Question 15

What’s the purpose of a lumbar puncture?

Answer 15

1) withdraw CSF for chemical analysis
2) inject therapeutic agent for cancer or meningitis
3) measure ICP and spinal fluid dynamics
4) inject contrast medium for diagnostic procedure

Question 16

A spinal tap is drawn from a patient that has a cloudy color and has 70mg/dL of protein. Is this typical? What could this indicate?

Answer 16

no - should be colorless/crystal clear

no - protein should be between 15-45 for adult, 15-100 for neonates

• high protein, cloudy appearance can occur with a tumor or inflammatory process

Question 17

With meningitis and inflammatory processes, would you expect a higher or lower pressure with a CSF anaylsis?

Answer 17

high pressure for intracranial tumors, abscesses, miningitis, inflammatory processes, subarachnoid hemorrhage, cerebral edema, and thrombosis of venous sinuses

Question 18

With severe dehydration, would you expect increased or decreased pressure in CSF?

Answer 18

decreased pressure for leaking CSF, subarachnoid block circulatory collapse, severe dehydration

Question 19

What does EMG look at?

Answer 19

electrical activity from muscles, both at resting/active contraction states

Question 20

Increased insertional activity in an EMG is indicative of what?

Answer 20

denervated muscle, many muscle diseases

Question 21

What is nerve conduction velocity testing?

Answer 21

conduction velocities obtained by stimulating peripheral nerves through skin and recording muscle/ sensory nerve action potentials

Question 22

How is NCV testing measured?

Answer 22

distance between two points is divided by conduction time

Question 23

In what diseases might we see decreased conduction velocities?

Answer 23

peripheral neuropathies characterized by decreased myelination (think low conduction)
- GBS, chronic demyelinating polyneuropathy, charcot marie tooth disease

Question 24

If we see a slowed conduction time with nerve conduction velocity testing, does that mean this person has a LMN issue?

Answer 24

not necessarily, could mean just focal compression of peripheral nerve