Magnetic resonance angiography of experimental cerebral vasospasm

The purpose of this study was to observe spastic cerebral arteries by magnetic resonance angiography (MRA) and to establish acetazolamide reactivity of these vessels. After control studies using MRA and conventional angiography, subarachnoid haemorrhage (SAH) was induced on day 0 in 7 Japanese monkeys. MRA and conventional angiography were then repeated on day 7 to observe the development of cerebral vasospasm. Reactivity of cerebral vessels to acetazolamide was also studied in both control animals (angiography before SAH) and on day 7 after SAH. Cerebral vasospasm was detected by both conventional angiography and MRA on day 7. The arteries on the side of the clot were more spastic than those on the control side. MRA was superior to conventional angiography in demonstrating dilatation of both control arteries (before SAH induction) and vasospastic arteries (on day 7 after SAH) after administration of acetazolamide.