Diffuse vasospasm after pretruncal nonaneurysmal subarachnoid hemorrhage.

Pretruncal (perimesencephalic) nonaneurysmal hemorrhage is a benign form of subarachnoid hemorrhage (SAH). Angiographic changes of vasospasm are uncommon in patients with this type of hemorrhage, and if vasospasm is present, it is mild and focal. We report two patients with pretruncal nonaneurysmal SAH who developed severe and diffuse vasospasm, expanding the clinical spectrum of this type of SAH. The first patient was a 40-year-old woman who suffered pretruncal nonaneurysmal SAH. Angiography performed on the seventh day post hemorrhage showed diffuse and severe vasospasm affecting both the anterior and the posterior circulation. The patient was treated with hypervolemia, and she remained asymptomatic. Follow-up angiography showed resolution of the vasospasm. The second patient was a 67-year-old woman who suffered pretruncal nonaneurysmal SAH. The results of the initial angiography were normal. Repeat angiography on the ninth day post hemorrhage showed severe vasospasm in the anterior circulation and moderate vasospasm in the posterior circulation. Nine hours later, the patient developed transient dysphasia, and she was treated with hypervolemia. Three days later, a transcranial Doppler examination showed normalization of blood velocities. The presence of diffuse and severe vasospasm does not exclude a diagnosis of pretruncal nonaneurysmal SAH.