Q9'1' Diagnosis Please

1
9.1a
9.1b
9.1c
9.1d
Post-contrast Axial T1-wtd image
T1-wtd image
FLAIR Image
Diffusion weighted image (DWI)
Diffusion weighted image (DWI)
9.1e
9.1f
47 year-old left handed gentleman with one day
history of somnolence, left facial droop and
slurred speech.
Q9.1. Diagnosis Please
Post-contrast coronal T1 wtd image
MRA Circle of Willis
2
Q9.2. Diagnosis Please
9.2a
9.2b
9.2c
9.2d
Post-contrast Axial T1-wtd image
(DWI) image
T1-wtd image
FLAIR Image
51 year-old patient multiple myeloma presented
with acute onset of right side weakness leading
to MRI of the brain 3 days later.
51 year-old patient multiple myeloma presented
with acute onset of right side weakness leading
to MRI of the brain 3 days later.
51 year-old patient with multiple myeloma
presented with acute onset of right sided
weakness leading to MRI of the brain 3 days
later.
3
Q9.3. Diagnosis Please
9.3a
9.3b
9.3c
9.3d
Post-contrast Axial T1-wtd image
T1-wtd image
FLAIR Image
Diffusion weighted image (DWI)
9.3e
9.3f
72 year-old left handed white man with history of
chest pain, 5 days prior to MRI, which subsided.
Patient went to a gas station and could not read
the credit card and signs in the gas station and
was unable to read the magazines in the doctors
office. Neurological examination revealed alexia
without agraphia.
Post-contrast coronal T1 wtd image
MR Angiography Neck
4
Q9.4. Diagnosis Please
June 29, 2004
July 30, 2004
9.4a
9.4b
9.4c
9.4a. Non-contrast CT Brain
9.4b. Non-contrast CT Brain
9.4c. Non-contrast CT Brain
Patient is status post recent right temporal
craniectomy for extensive right middle fossa
skull-based meningioma, with follow-up
post-operative CT images.
5
Q9.5. Diagnosis Please
9.5a
9.5b
9.5c
9.5d
Diffusion weighted image (DWI)
T1-wtd image
FLAIR Image
Post-contrast Axial T1-wtd image
9.5e
58 year-old male with history of renal cell
carcinoma presented with 3 weeks history of
dressing apraxia consisting of difficulty in
performing routine tasks such as getting dressed,
tying his shoes, difficulty with recall and
inferior quadrantopsia with no focal motor
deficits. Symptoms slowly improved.
Differential diagnosis Stroke versus
metastasis.
Post-contrast sagittal T1 wtd image
6
Q9.6. Diagnosis Please
July 31, 2003
9.6a
9.6b
9.6c
9.6d
9.6e
9.6f
9.6g
9.6h
DW Image
FLAIR Image
T1-wtd image
Post-contrast Axial T1-wtd image
December 31, 2003
73 year-old male with stage IV non-small cell
carcinoma presented with 2 weeks history of
sudden onset of speech difficulty with difficulty
in word finding, symptoms gradually improved.
Clinical diagnosis Stroke versus metastasis.
7
9.1a
9.1b
9.1c
9.1d
9.1e
9.1f
Diagnosis Acute one day old infarction
involving the right middle cerebral artery (MCA)
territory.
Diffusion weighted image (DWI)
Acute infarction is seen as an area of increased
signal intensity on DWI (arrow in A), FLAIR image
(arrow in B), with no evidence of hemorrhage on
T1-wtd image (C) and no enhancement on post
contrast images (D). Intravascular enhancement
also an indication of acute stroke is shown on
coronal T1 weighted image (arrow in F). MR
angiography of circle of Willis demonstrates
small caliber of right Sylvian branches of MCA
(arrows in E) when compared to the normal side.
8
9.2a
9.2b
9.2c
9.2d
Post-contrast Axial T1-wtd image
DWI
T1-wtd image
FLAIR Image
Diagnosis Small acute 3 day old infarction
involving the left insular cortex, the territory
of left MCA, best noted on diffusion weighted
image (arrow in A) and with enhancement (arrow in
D).
9
9.3e
9.3f
9.3a
9.3b
9.3c
9.3d
Diagnosis Acute infarction (5 day old)
involving the left posterior cerebral artery
(PCA) territory.
Diagnosis Acute infarction (5 day old)
involving the left posterior cerebral artery
(PCA) territory.
The area of infarction is seen as an area of
increased signal intensity on DWI (arrow in A)
and FLAIR image (arrow in B) involving the left
posterior temporal-occipital lobe. Mild
enhancement seen on post contrast images (arrow
in D and F). Figure E represents screening 2D
time of flight MR angiogram of the neck vessels
revealing no obvious occlusion of major vessels
in the neck.
10
June 29, 2004
July 30, 2004
9.4a. Non-contrast CT Brain
9.4b. Non-contrast CT Brain
9.4c. Non-contrast CT Brain
Non-contrast CT brain on 8 days post-operatively
demonstrated a focal area of low attenuation
within the right frontal lobe cortex (arrow in A)
and adjacent white matter representing acute
infarct.
Scan done a month later (B C) demonstrated a
massive acute/subacute infarct involving the
right MCA territory (white arrows in B C) and
ACA (anterior cerebral artery) territory (yellow
arrow in C) with mass effect and subfalcine
herniation to the left (fig. B).
11
Q9.5. Diagnosis Please
9.5a
9.5b
9.5c
9.5d
Diffusion weighted image (DWI)
T1-wtd image
FLAIR Image
Post-contrast Axial T1-wtd image
Diagnosis Subacute infarct 3 weeks old
involving the right middle cerebral (MCA) artery
territory.
9.5e
Abnormal T2 wtd hyperintensity involving the
right posterior temporal-parietal-occipital lobe
with gyral thickening best noted on FLAIR image
(arrows in B). Subacute blood outlining the
cortex is best seen on pre-contrast T1-wtd image
(arrows in C). There is no definite contrast
enhancement obscured by bright signal intensity
of blood. The right MCA territory infarct is
also shown on sagittal post contrast T1-wtd image
(arrows in E). Diffusion weighted image reveals
bright signal intensity (arrows in A) involving
the cortex from restricted diffusion, an
important sequence in the diagnosis of acute
stroke.
Post-contrast sagittal T1 wtd image
12
Q9.6. Diagnosis Please
July 31, 2003
9.6a
9.6b
9.6c
9.6d
Diagnosis Non-hemorrhagic subacute enhancing
infarct (2 weeks old) involving the left basal
ganglia region. Subacute infarct is seen as an
area of increased signal intensity on FLAIR image
(arrow in B) and bright signal intensity on DWI
(arrow in A). Enhancement of the infarct is
shown on post contrast image (arrow in D).
A repeat MRI scan done 5 months later showed
resolution of infarct and no evidence of bright
signal intensity on diffusion weighted image E. 5
months old infarct.
9.6e
9.6f
9.6g
9.6h
December 31, 2003
13
Imaging Findings of Stroke
Acute Stroke (up to 7 days)

• MR imaging of the brain is far more sensitive
  than CT imaging to recognize acute infarction.
• Diffusion wtd. pulse sequence (DW imaging) is
  the most sensitive MR sequence to demonstrate
  stroke. This sequence is sensitive to restricted
  diffusion within the cell from stroke-induced
  cytotoxic edema and the region of acute stroke is
  seen as an area of bright signal on DWI (Figs.
  1a, 2a). Cytotoxic edema can occur immediately
  after the initial insult thus DWI images can
  reveal, the area of acute infarct immediately
  after the insult.
• Intravascular contrast enhancement, another sign
  of early stroke (Figure 1f).
• Sulcal effacement, gyral edema (Fig. 5b), loss
  of gray-white matter interface can occur within
  12 hours of stroke.
• Parenchymal contrast enhancement (Fig. 6d), mass
  effect (Fig. 4b) and hemorrhage can occur within
  1-7 days of insult.

1a
2a
5b
6d
Subacute infarct (1 week to 8 weeks)

• Contrast enhancement slowly decreases in time
  but can persist for 8 weeks, with decreasing mass
  effect and abnormal signal intensity

Old Infarct
4b

• Focal area of encephalomalacia
• Porencephalic dilatation of adjacent ventricle.
• Residual old blood products may be present.

6e