Neuroradiology Pics

Question 1

Describe appearance of blood on T1 imaging in days 1-120 of IPH

Answer 1

Blood on T1: starts off isointense

Day 1: isointense bleed but can see mass effect and interventricular shfit

Day 21: subacute bleed is hyperintense on T1

Then chronic (120 days) is hypointense again

Question 2

Hyperdense vs. hyperintense

(a) Enhacing

Answer 2

Density = CT

Intensity = MRI

(a) Enhancing = breakdown of BBB, lights up when given contrast (on either CT or T1 MRI)
- enhancing on MRI = hypointense on pre-contrast image, hyperintense on post-contrast T1

Question 3

(a) Type of image
(b) Findings

Answer 3

(a) Axial FLAIR
(b) Extensive white matter disease, mainly left temporal and b/l ocipital lobes

Dx = amyloid beta related angiitis

Question 4

(a) Dx
(b) Plane of section

Answer 4

(a) Right putamen hemorrhage
(b) Axial plane

Question 5

(a) Locate the hemorhhage
(b) Type of image

Answer 5

(a) Hemorrhage in the right putamen
(b) Axial and sagittal FLAIR
- white matter dark, grey matter light, CSF blacked out

Question 6

54 yo F develops HA and collapses at home, unconscious on exam

(a) Dx
(b) What is the red arrow indicating?
(c) Highest risk factor for this?

Answer 6

(a) Left basal ganglia hemorrhage (IPH = intraparenchymal hemorrhage) w/ intraventricular extension
(b) Red arrow showing extension of hemorrhage into the 4th ventricle
(c) chronic HTN

Question 7

MRI findings of amyloid angiopathy

Answer 7

White matter hyperintensities (usually asymmetric) and micro-bleeds in multiple lobes of the brain

-lesions shrink w/ improvement in symptoms (or successful tx w/ immunosuppressants) and enlarge w/ recurrences

Question 8

Stroke of which arteries?

Answer 8

(1) Superior cerebellar artery
(2) Anterior inferior cerebellar artery
(3) Posterior inferior cerebellar artery

Question 9

Name the type of bleed

Answer 9

(1) Epidural
- doesn’t cross suture lines
(2) Subdural
- crescent shaped
(3) Subarachnoid
- into the circle of willis, dooming ‘star’ sign

Question 10

What is a STIR sequence?

Answer 10

Sequence used on MRI of the spine- T2 image (white matter dark, grey matter white) where fat signal is supressed

-image is in the sagittal plane

Question 11

Features of FLAIR MRI

(a) Color of brain matters
(b) Color of CSF
(c) Color of BVs

Answer 11

FLAIR MRI = T2 image w/ the CSF blacked out

• often the most helpful
  (a) White matter dark, grey matter white
  (b) CSF dark
  (c) BVs dark

Question 12

75 yo M w/ sudden onset HA and left homonomyous hemianopsia

Locate the lesion

Answer 12

Lesion = right occipital lobe

-lobar hemorrhage (lobe adjacent to cortex, not deep structure like basal ganglia)

Most likely etiology = amyloid

Question 13

Locate the lobar hemorrhage

Answer 13

(e) frontal
(f) temporal
(g) pareital
(h) occipital

Question 14

Features of head CT

(a) Color of brain matter

(b) Color of bone
(c) Color of acute clot/hematoma

Answer 14

Head CT:

(a) Gray matter (medial) is darker than white matter (lighter)
(b) Bone is white
(c) Acute clot/hematoma = white

Question 15

Name the type of image

Answer 15

(1) On the left = T1
- white matter white, gray matter gray, CSF dark
(2) On the right = FLAIR
- white matter dark, grey matter light, CSF dark

Question 16

Name the two circled physiologically calcified structures

Answer 16

Yellow = pineal gland

Red = choriod plexus

Question 17

63 yo F p/w sudden onset sever HA w/ confusion and blurry vision
-b/l abducens nerve palsies

Dx

Answer 17

Dx = pituitary apoplexy = bleeding in pituitary fossa

Question 18

Vasogenic vs. Cytotoxic edema

(a) Where is the fluid

(b) Etiology
(c) Appearance on CT

Answer 18

Cytotoxic edema

(a) Fluid is in the intracellular space
(b) Ischemia, cell membrance injury (NaK pump dysfunction) causes accumulation of intracellular fluid
(c) Loss of grey/white jxn

Vasogenic edema

(a) Fluid pushed into the interstitial space => tends to accumulate where there is more interestitial space (white matter b/c grey matter is too packed w/ cell bodies)
(b) Etiology = local insult- tumor, toxo, Tb, abscess
(c) On CT: see preservation of grey-white jxn b/c increased extracellular fluid makes the white matter appear even less dense

Question 19

Features of T1 MRI

(a) Color of the matters and CSF

Answer 19

T1 MRI- great for seeing normal anatomy

(a) White matter is white, grey matter is grey, CSF Is dark

Question 20

(a) Describe what is meant by restricted diffusion
(b) Examples

Answer 20

Restricted diffusion = bright on DWI (diffusion weight image) b/c water molecules are stuck in the area (slow diffusion)

• while dark on ACD
  (b) Restricted diffusion seen most classically in ischemic stroke
• can also be seen in some tumors, active MS lesions, and abscesses

Question 21

(a) Locate the hemorrhage
(b) Prognosis

Answer 21

(a) Pontine hemorrhage
- from branches of the basilar artery that penetrate into the pons
(b) Very poor prognosis- immediately quadraplegic, decerebrate posturing, comatose, very minimal meaningful recovery (if any)

Question 23

Features of T2 MRI

(a) Color of brain matter
(b) Color of CSF
(c) Color of blood vessels

Answer 23

T2 MRI

• T1 vs. T2 has to do w/ the relaxation of the particles
  (a) White matter is dark, grey matter is light
  (b) CSF is bright white
  (c) BVs are dark

Question 24

Locate the lesion of

(a) Unilateral homonymous hemianopsia
(b) Bitemporal hemianopsia

Answer 24

(a) Unilateral homonymous hemianopsia 2/2 lesion of the optic tract
- or if macular sparing (hard to determine on exam), lesion localizes to the occipital lobe
(b) Bitemporal hemianopsia 2/2 lesion of the optic chiasm

Question 25

Name the planes of section

Answer 25

(1) Axial
(2) Coronal
(3) Sagittal

Question 26

Locate the hemorrhage

Answer 26

Thalamus

(two dif pts)