[Management for subarachnoid hemorrhage with negative initial angiography].

Subarachnoid hemorrhage (SAH) is commonly caused by ruptured aneurysm or arteriovenous malformation which is detected by cerebral angiogram. However, since angiograms sometimes cannot show the origin of SAH, we review 12 cases (6.3% of total SAH) to assess the management of these cases. We divided the 12 cases into three groups. Group A (occulted aneurysm group) consisted of six cases of which aneurysms were detected by repeated angiographies in four, and by surgical procedures in two. Group U (unknown etiology group) consisted of five cases. Their follow up periods varied from 7 months to 7 years 11 months, and all of them recovered well and had no episode of rebleeding. Group R (rebleeding group) consisted of one case which fatally re-bled on the second day. Group A tended to be Hunt and Hess grade 3, and Fisher group 3 or 4. In contrast, group U tended to be H and H grade 1 or 2, and Fisher group 2. However by their clinical and neuroradiological findings alone, it was not possible to distinguish the two groups certainly. This means that the patients whose initial angiography does not show the origin of bleeding must be cared for as an occult aneurysm case. Twice repeated angiograms should be programmed. In our cases the first was carried out on the seventh day in the hope that the reason for vasospasm of the parent artery might be shown to be a hidden aneurysm. The second was carried out sometime between the 14th and 21st day because of thrombolysis in the aneurysm, and because it was necessary to relieve vasospasm.(ABSTRACT TRUNCATED AT 250 WORDS)