Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MHD2 > Block 8 (Neuro) - Online Learning - Neuroimaging Essentials > Flashcards

Block 8 (Neuro) - Online Learning - Neuroimaging Essentials Flashcards

1
Q

What are the two primary methods of imaging the nervous system?

A
  1. MRI

2. CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which method of imaging is best for imaging the brain and spinal cord?

A

MRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Compare the views obtained from MRI vs. CT.

A

MRI: axial, sagittal, coronal
CT: axial (need reformatting to obtain other views)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Compare the radiation exposure of MRI vs. CT.

A

MRI - none

CT - radiation exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Compare the scanning times of MRI vs. CT.

A

MRI: longer scanning time (patient movement degrades images)
CT: shorter scanning time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are two other limitations of MRI?

A

Prohibited in presence of pacemakers or certain implanted metal

Tight, enclosed scanner is difficult for claustrophobic patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Compare the contrast agents used in MRI vs. CT.

A

MRI: gadolinium
CT: iodine-based

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is highlighted in T1W vs. T2W MRI?

A

T1W: highlights anatomy
T2W: highlights pathology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does CSF appear in T1W vs. T2W MRI?

A

T1W: CSF is dark (low signal)
T2W: CSF is bright (high signal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is FLAIR?

A

Fluid attenuation recovery - like T2W, but the visually distracting high signal of CSF is removed from the images

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some of the abnormalities detected by neuroimaging (8)?

A
  1. Acute intracranial hemorrhage
  2. Acute cerebral infarction
  3. Mass effect or edema
  4. Hydrocephalus
  5. CNS infection
  6. Brain tumors
  7. MS
  8. Degenerative spine disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does acute hemorrhage appear on CT?

A

Hyperdense (bright or white)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does hemorrhage appear on CT over time?

A

As time passes, edema subsides and the hematoma becomes isodense (days 3-15) and then hypodense (dark or black) on CT (after day 15)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does hemorrhage appear on MRI (T1W/T2W) initially?

A

T1W: isointense
T2W: bright

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does hemorrhage appear on MRI (T1W/T2W) over time? What leads to this change?

A

T1W: progresses from isointense to bright to dark (chronic)

T2W: progresses from bright to dark to bright to dark rim (chronic)

Progression of blood (oxy-Hb -> met-Hb -> hemosiderin and ferritin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does acute infarction appear on MRI?

A

T2W or FLAIR - high signal (bright)

17
Q

What provides the earliest infarct detection and why?

A

DWI (diffusion weighted imaging) - water diffusion is impaired in an ischemic brain

18
Q

How does acute infarction appear on CT?

A

Hypodensity

19
Q

How does edema appear on CT?

A

Hypodensity

20
Q

How does edema appear on MRI T2W or FLAIR?

A

Increased, high signal intensity

21
Q

What part of the brain is mainly involved in edema?

A

White matter (spares cortical gyri fingers)

22
Q

What is hydrocephalus?

A

Ventricular enlargement without loss of brain tissue, related to impared CSF flow

23
Q

What are the 2 major causes of hydrocephalus and how are they different?

A

Aqueductal stenosis: enlarged lateral and 3rd ventricles (not 4th)

Scarring or blockage of subarachnoid villi: enlarged lateral, 3rd, and 4th ventricles

24
Q

How does an abscess appear?

A

Cavitary, encapsulated lesion (walled-off hole) with surrounding edema; better visualized when the capsule is delineated by contrast

25
Q

Multiple abscesses may mimic ___.

A

Metastatic cancer

26
Q

How does encephalitis or myelitis appear?

A

Focal edema with variable enhancement

27
Q

How does meningitis appear?

A

Leptomeningeal enhancement may occur

28
Q

How do primary brain tumors appear?

A

Solitary, may be irregularly shaped, hemorrhagic or heterogenous

29
Q

How do metastatic brain tumors appear?

A

Solitary or multiple, spherical, at gray-white matter junction

30
Q

How do epidural spinal cord metastases appear?

A

Arise from vertebral bone and encroach upon spinal cord in its canal

31
Q

How does MS appear and what is it seen best with?

A

Plaque lesions in the periventricular white matter, brain stem, or spinal cod; high signal lesions on T2W or FLAIR

32
Q

MS lesions may appear similar to ___.

A

Chronic ischemic white matter lesions

33
Q

What are Dawson’s fingers and when are they seen?

A

Radially arranged lesions in the periventricular area; MS

34
Q

What are some degenerative spine diseases?

A

Spondylosis
Herniated discs
Spinal stenosis

35
Q

If MRI cannot be done, how can degenerative spine diseases be visualized?

A

Spinal CT with intrathecal contrast

MHD2 (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions