Postoperative measurements of regional cerebral blood flow (rCBF) were performed in 27 patients with ruptured intracranial aneurysms to investigate the relation of rCBF to vasospasm and to the cerebral ischemic neurological deficits. The clinical materials were 27 patients (14 males and 13 females) who underwent the definitive surgery (clipping or coating) for their ruptured intracranial aneurysms. None of them developed the ventricular dilatation nor intracerebral hematoma.
Using Novo Cerebrograph® with 133xenon inhalation method, rCBF studies were conducted in each patient at postoperative one and two weeks. The hemispheric mean value of initial slope index was estimated in both hemispheres. According to its extent, angiographic vasospasm was classified into four types. If a patient deteriorated neurologically in the absence of intracerebral hematoma or ventricular dilatation, the neurological deterioration was regarded as the cerebral ischemic neurological deficits due to vasospasm.
The results were as follows:
1) In both hemispheres the cerebral blood flow (CBF) of postoperative two weeks was greater than that of postoperative one week.
2) According to its extent of their angiographic vasospasm, patients were classified into four groups; nospasm, diffuse-mild, diffuse-severe and peripheral. Peripheral group showed most greatly decreased CBF in four groups. The decrease of CBF in diffuse-severe group was the next greatest. The CBF of diffuse-mild and no-spasm groups was not decreased in any hemisphere.
3) Patients who developed the cerebral ischemic neurological deficits due to vasospasm showed significantly decreased CBF in both hemispheres in comparison with those who did not develop the neurological deficits.
In conclusion there is the significant relationship of rCBF to the presence of vasospasm and of the cerebral ischemic neurological deficits, and the rCBF studies are very important for understanding the pathophysiology of vasospasm in patients with ruptured intracranial aneurysms.
