T. Toriyama et al., FUNCTIONAL IMAGE OF DYNAMIC COMPUTED-TOMOGRAPHY IN DIAGNOSTIC AND PROGNOSTIC EVALUATION OF ISCHEMIC STROKE WITHIN THE 1ST 6 HOURS, Stroke, 24(12), 1993, pp. 1933-1944
Background and Purpose: It is important to make a diagnosis before a l
ow-density area appears on computed tomography for appropriate managem
ent of acute ischemic stroke. We report the diagnostic and prognostic
usefulness of functional image of dynamic computed tomography for acut
e ischemic stroke. Methods: Forty-seven patients with ischemic strokes
within 6 hours of ictus underwent dynamic computed tomography in whic
h functional images were obtained. These findings were compared with a
ngiographic findings, follow-up computed tomography, and clinical outc
ome. Results: The functional images were categorized into three groups
: (1) cortical type: abnormalities on time to peak image and/or correc
ted mean transit time image involving mainly cortical structures (29 c
ases); (2) noncortical type: abnormalities on either or both images li
mited to noncortical structures (7 cases); and (3) normal type: no abn
ormalities on both images (11 cases). Cortical type as a diagnostic te
st for arterial trunk occlusion had a good sensitivity (100%), specifi
city (95%), and accuracy (98%). Infarction volume on follow-up compute
d tomography correlated with extension of prolonged time-to-peak area
(r=.80, P<.01) and that of prolonged corrected mean transit time area
(r=.81, P<.01). Cortical type was associated with significantly unfavo
rable outcome (P<.01). Conclusions: Functional image of dynamic comput
ed tomography findings predicted arterial trunk occlusion, infarction
volume, and clinical outcome. Therefore, this technique would be usefu
l not only for indicating definitive angiography and subsequent therap
y but for evaluating the effectiveness of surgical or medical recanali
zation.