Acute infarction cerebral

1. Acute left hemepersisis
•A 70-year-old woman presented to the
emergency room with an acute onset of left
arm weakness, difficulty walking and
slurred speech. Significant findings on
physical exam included blood pressure of
180/100 mm Hg, dysarthria and decreased
motor strength in left upper and lower
extremities. Her laboratory values were
within normal limits.

2. CT
•Computed
tomography of the
head shows increased
attenuation in the right
middle cerebral artery
(MCA), consistent
with right MCA
thrombosis (arrow).

3. CT
•The right lentiform
nucleus is obscured (
arrow)

4. CT
•effacement of the sulci
in the right
hemisphere along the
right MCA territory (
arrow). These findings
are consistent with
acute right MCA
thrombosis and right
hemispheric infarction

5. MRI
•Magnetic resonance
(MR) imaging
performed two days
confirms a large
territorial infarct in the
right MCA
distribution with mild
mass effect on the
right lateral ventricle (
arrow).

6. MRA
•The MR angiogram
demonstrates
diminished caliber and
signal intensity of the
right MCA and its
distal branches (arrow

7. Discussion
•Although head CT scans obtained within the first few hours after stroke are
normal in 60% of patients, several early signs can be seen in strokes less than
6 hours old. These signs include increased attenuation in the middle cerebral
artery (dense MCA sign), loss of gray-white junction along the insula (insular
ribbon sign), obscuration of the lentiform nucleus, and effacement of the sulci
along the cortex. When the initial CT scan is normal, a repeat scan in 48 hours
will, in about 80% of patients, show the infarct as an area of decreased
attenuation with mass effect on the adjacent structures.
•MRI is more sensitive than CT in identifying and localizing acute cerebral
infarcts. Vascular flow related abnormalities can be seen on contrast-enhanced
MRI within minutes of symptom onset. However, standard MRI sequences fail
to detect acute infarct in 10-20% of patients. MRI/MRA are often helpful as
follow-up studies to evaluate the extent of infarction, presence or absence of
hemorrhage, and degree of stenosis of the cerebral vessels. In patients with
persistent transient ischemic attacks, the combination of a carotid vascular
ultrasound and MR angiogram may obviate the need for a carotid angiogram.