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Nontraumatic subarachnoid hemorrhage: value of repeat angiography.

PURPOSE
To evaluate the benefits and risks of repeat cerebral angiography in patients with subarachnoid hemorrhage of unknown cause.


MATERIALS AND METHODS
Findings from 391 angiographic examinations (323 initial, 68 repeat) were retrospectively reviewed in 323 patients with nontraumatic subarachnoid hemorrhage to determine the cause of bleeding and the frequency of complications with neurologic deficit.


RESULTS
At the initial angiographic examination, aneurysms were found in 195 patients (60.4%), and arteriovenous malformations were found in 11 patients (3.4%). Sixty-six patients with negative findings at initial examination underwent repeat cerebral angiography. Three additional aneurysms were detected, all of which could be seen retrospectively on the initial angiogram. In 63 patients, the cause of bleeding remained unexplained. Complications of the 391 angiographic examinations were definitive neurologic deficits in one patient (0.2%) and transient deficits in seven patients (1.8%).


CONCLUSION
Repeat angiography is not necessary in patients with subarachnoid hemorrhage if technically good, carefully evaluated digital subtraction angiography was performed initially. Repeat angiography seems to be justified only when the initial examination is technically inadequate, when vasospasm is present, or if further bleeding occurs.