Abstract
Reconstructive vascular surgery for TIA and RIND has been generally accepted. However the surgical indication of STA-MCA anastomosis for completed stroke is still controversial. In this report, we intended to evaluate an indication for extra-intra cranial anastomosis for completed stroke based on rCBF measurement and computed tomography. 38 patients with supratentorial ischemic cerecrovascular disease (TIA: 11, RIND: 11, completed stroke: 16) were investigated by angiography, CT scan and rCBF. rCBF was measured simultaneously over 16 regions of one hemisphere by non-invasive 133Xe inhalation method. CT classification of supratentorial ischemic cerebrovascular disease are as follows. Ia: normal, Ib: brain atrophy, II: small size of focal low density, III: moderate size of focal low density, IVa: multi-focal low density, IVb: multi-lobar low density, IVc: diffuse low density.
It was revealed the small size of focal low density includes three clinical type (TIA: 4, RIND: 6, completed stroke: 6). It means those cases with three different clinical symptom had a same morphological lesion. All cases of this group shows relative small infarction localized in the basal ganglion or corona radiata on CT (so called“strategic infarction”). This result suggests that a boundary zone of reversibility of neurological symptom is found in this group. However, rCBF study in this group revealed various pattern, TIA showed slightly reduction of mean rCBF. In RIND the affected hemisphere showed moderately increased mean rCBF rather than unaffected side. Some number of these completed stroke were designated as minimal global reduction superimposed a relative focal ischemic area. The remainder had a severely generalized reduction of flow over the hemisphere.
In conclusion, cases showed small size of focal low density and minimal reduction of flow with relative focal ischemic area, even if they are clinically classified into complet stroke, are desirable candidates for STA-MCA anastomosis.
