DETECTION OF DELAYED CEREBRAL VASOSPASM, AFTER RUPTURE OF INTRACRANIAL ANEURYSMS, BY MAGNETIC-RESONANCE ANGIOGRAPHY

OBJECTIVE: The goal of this study was to assess the value of magnetic resonance angiography (MRA), compared with conventional angiography, i n the diagnosis and follow-up monitoring of delayed cerebral vasospasm after subarachnoid hemorrhage resulting from rupture of intracranial aneurysms. METHODS: For 32 patients undergoing examination by both MRA and conventional angiography during the period of risk for vasospasm, on the same day, the frequency and severity of and sequential changes in vasospasm were evaluated. The three-dimensional time-of-flight met hod was used. MRA was performed three times, i.e., before, during, and after the period of risk for vasospasm. Conventional angiography was performed twice, i,e., at admission and during the period of risk for vasospasm. Vasospasm was assessed at 22 regions of the cerebral arteri es, including the bilateral anterior cerebral (A1, A2, and A3 segments ), middle cerebral (M1, M2, and M3 segments), internal carotid (C1 and C2 segments), posterior cerebral (P1 and P2 segments), and posterior communicating arteries. RESULTS: Seven patients were excluded because of poor MRA images. Twenty-two of 25 patients (125 arteries) showed va sospasm in conventional angiograms. Nineteen of the 22 patients also s howed vasospasm in MRA images; however, 57 arteries (45.6%) were diagn osed as showing vaospasm by MRA, and 59 (47.2%) could not be evaluated because of artifacts. For the remaining three patients (nine arteries , 7.2%), vasospasm could not be detected by MRA. Sequential changes in vasospasm could be well evaluated by MRA. CONCLUSION: MRA could be us eful for management of cerebral vasospasm, although it cannot become a practical alternative to conventional angiography.