gms | German Medical Science

Objective: Long-term magnetic resonance angiography (MRA) follow-up studies on patients with cryptogenic nonperimesencephalic subarachnoid hemorrhage (SAH) are scarce. This study is designed to evaluate the incidence of de novo aneurysms after cryptogenic nonperimesencephalic SAH and persistent vasospastic lesions caused by initial SAH within this population in a follow-up a decade after initial hemorrhage.

Method: In 20 patients, high-resolution 3T magnetic resonance imaging (MRI) including time-of-flight magnetic resonance angiography (TOF-MRA) and contrast-enhanced magnetic resonance angiography (ceMRA) were performed a decade after idiopathic SAH. MRA follow-up imaging was compared with digital subtraction angiography (DSA) and CT or MRA angiography at the time of bleeding. Furthermore, post-hemorrhage images were related to current MRI with special reference to persistent vasospastic lesions.

Results: We identified 20 patients with a nonperimesencephalic SAH, 11 (55%) patients were male, and 9 (45%) were female. Mean age at the time of hemorrhage was 51.7± 14.4 years (range 5 to 74 years). Mean time of MR imaging after initial hemorrhage was 10.1 ± 2.8 years. Among the study population, a de novo aneurysm formation could not be detected. Post-hemorrhage vasospasm-related lesions were detected in only one patient. In one patient follow-up MRA 8 years after bleeding showed a 2 mm x 1.7 mm aneurysm of the right posterior communicating artery. This aneurysm was retrospectively visible in post-hemorrhage DSA. Since then its morphology and extension were stable.

Conclusions: According to our results, patients with idiopathic nonperimesencephalic subarachnoid hemorrhage do not exhibit a higher risk for de novo aneurysms. Within our population, persistent vasospasm-related lesions after cryptic nonperimesencephalic SAH are significantly lower compared to aneurysmal nonperimesencephalic SAH.