It has been reported lately that extra-intra cranial arterial bypass procedure (EC-IC bypass procedure) had a protective effect against further clinically significant cerebro-vascular accidents in patients of transient ischemic attack (TIA) or reversible ischemic neurological dificit (RIND). It was however reported not effective for improving the neurological deficit of patients with complete stroke. We clinicians know from the experience that EC-IC bypass procedure takes sometimes good effect for the motor weakness of the patents with minor complete stroke.
It is the purpose of this report to clarify the indication of the EC-IC bypass procedure especially for the patients with minor completed stroke by the investigation of angiogram, CT findings and clinical results.
The cases consist of 31 cases, in which CT was taken and clinical courses were followed up after more than a half year.
These cases were classified by CT as: (1) diffuse large low density area (2) small locarized low density area in the internal capsule (3) small locarized low density area in the paraventricle (4) small low density area in the arterial border zone (5) no low density area.
(Results) Regarding the cases of occlusion of MCA: the cases with diffuse large low density area became poor hospital course. The cases with small locarized low density area in the paraventricle were better in clinical course than cases with low density area in the internal capsule. Regarding the cases of occlusion of IC with border zone infarction were well in hospital course.
The cases that could move the paralytic hand just after the EC-IC bypass procedure were only the cases with small low density area in paraventricle or border zone infarction or no low density area. If the CT revealed low density area in the internal capsule even surgery couldn't enable the minor stroked patients to move the paralytic hand.
(Conclusion) EC-IC bypass procedure is effective not only as a protection against another ischemic attack but also for a motor weakness of minor completed stroked patients of the following cases: 1 cases of occlusion of middle cerebral artery without low density area in the internal capsule by CT. 2 cases of occlusion of internal carotid with low density area in the arterial border zone by CT.
