Xenon contrast-enhanced CT imaging of supratentorial hypoperfusion in patients with brain stem infarction.
OBJECTIVE
The characteristics of hypoperfusion in the supratentorial region of patients with brain stem infarction are unclear. We investigated the relationships between the presence of hypoperfusion and the location, number, and size of the infarcts with xenon contrast-enhanced CT.


METHODS
One hundred five patients with brain stem infarction detected by MR imaging underwent xenon contrast-enhanced CT to measure the regional CBF (rCBF) in the frontal, temporal, parietal, and occipital regions and in the putamen and thalamus. A decrease of more than 10% from the mean rCBF value for normal individuals was considered to indicate hypoperfusion.


RESULTS
Thirty-six patients had supratentorial hypoperfusion. The mean rCBF values (measured in mL/100 g/minute) were as follows: frontal region, 36.2 +/- 5.1 (-14.8%, n = 28); parietal region, 42.3 +/- 4.7 (-19.1%, n = 29); temporal region, 41.5 +/- 2.8 (-12.6%, n = 12); and thalamus, 50.1 +/- 3.2 (-19.6%, n = 7). Supratentorial hypoperfusion was associated with pontine infarction in 33 patients (upper pons in 15, middle pons in 18, and lower pons in seven), midbrain infarction in two, and medulla infarction in one. Twenty-three patients had infarcts that were larger than 5 mm, and 11 had infarcts that were 2 to 5 mm. Only two had infarcts that were smaller than 2 mm. Seven patients each had one infarct, 13 each had two, and 16 each had three.


CONCLUSIONS
Supratentorial hypoperfusion was associated with larger infarcts, with more infarcts, and with pontine infarction.
Miyazawa
N
N
Department of Neurosurgery, Yamanashi Medical University, Nakakoma-gun, Japan.
Uchida
M
M
Fukamachi
A
A
Fukasawa
I
I
Sasaki
H
H
Nukui
H
H
D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D002545:Brain Ischemia / Q000000981:diagnostic imaging*; D020526:Brain Stem Infarctions / Q000000981:diagnostic imaging*; D002540:Cerebral Cortex / Q000098:blood supply; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011699:Putamen / Q000098:blood supply; D012039:Regional Blood Flow / Q000502:physiology; D012680:Sensitivity and Specificity; D013788:Thalamus / Q000098:blood supply; D014057:Tomography, X-Ray Computed; D014978:Xenon
D003287:Contrast Media; D014978:Xenon