IMAGING & other DM lectures

Question 1

4 Types of Structural imaging

Answer 1

CT, CTA, MRI, MRA

Question 2

4 Types of functional imaging

Answer 2

EEG, MEG, fMRI, PET

Question 3

EEG & what it is used for

Answer 3

cheap way to measure brain waves/ electrical activity
used for seizure d/o, sleep d/o, changes in electrical activity
not detailed but could be ok for surgery

Question 4

MEG & pros/cons

Answer 4

measures magnetic field from neuronal electrical activity but electrodes don’t touch patient
pros- exact location of seizure, preoperative planning & epilepsy surgery, alzheimers, psych d/o, head injury
CONS- more costly then EEG, fMRI

Question 5

fMRI

Answer 5

measures metabolic fx, changes in o2 from brain activity
PROS- no radiation, good for pre-surgical brain maps
CONS- more expensive than EEG

Question 6

PET

Answer 6

radioactive tracer goes into vein then watch to see where its used in brain
good for evaluation of cancer and seizures that dont respond to meds, and memory d/o

Question 7

CT & Uses

Answer 7

cross-sectional xray images with radiation
uses- head trauma, hydrocephalus/ventricles, intracranial lesions, hemorrhage

Question 8

Why use CT

Answer 8

theres no magnets so its safe for ppl w/ metal
faster than an MRI

Question 9

Interpreting CTS

Answer 9

used for BBB
Blood & bone are white, brain is grey

Question 10

CTA

Answer 10

used for blood vessels and tissues
caution with renal fx bc it uses contrast

Question 11

MRI

Answer 11

uses magnets, radiowaves to make images; no radiation
avoid w/ ppl w/ metal

Question 12

Myelography

Answer 12

uses contrast dye & X-ray to look at spinal canal; can be paired w/ CT
pros- disk herniations, r/o nerve compression; good for ppl who cant get MRI
cons– invasive, radiation

Question 13

Ultrasound

Answer 13

uses- carotid artery patency, new born screening
pros- risk free, no radiation, portable
cons- operator-dependent, can’t use for brain after fontanelles have closed

Question 14

what is Bacterial meningitis? what is the classic triad sx?

Answer 14

infection of CNS membrane
triad–fever, neck stiffness, headache
also vomiting, seizures, photophobia

Question 15

what are signs of bacterial meningitis?

Answer 15

fever
bulging fontanelle
focal neurologic findings
papilledema
rash

Question 16

what are indications for lumbar puncture?

Answer 16

subarachnoid hemorrhage
CNS infection like meningitis
NS d/o like Guillain-barre, MS, etc
some cancers
Psuedotumor cerebri from excess CSF in brain

Question 17

infectious indications in children

Answer 17

fever of unknown origin
fever in child < 3 months
kid 3mon-3yo w/ fever, irritability, vomiting

Question 18

Kernig’s sign vs Brudzinski’s Sign

Answer 18

kernig’s sign: lay down flex hip & leg then straighten leg; pain & spasms= + for meningitis
brudzinski’s sign: flexion of neck causes legs to draw up
BOTH: test for meningitis, can be used in over 3 year old

Question 19

Contraindications for LP

Answer 19

infection in tissues near puncture site
increased ICP (papilledema–can do after imaging)
coagulopathy or less platelet count
lateralizing signs or signs of uncal herniation (spinal deformity)

Question 20

what are the two positions for lumbar puncture

Answer 20

lateral recumbent position
sitting position– increased risk of post-LP HA

Question 21

what is tuffier’s line?

Answer 21

the superior iliac crest intersection @ L4

Question 22

at what spinal level is needle inserted with lumbar puncture?

Answer 22

L3/4 in most adults
L5/5 or L5/S1 in kids