Objective: Subarachnoid hemorrhage from ruptured posterior inferior cerebellar artery (PICA) aneurysms is uncommon, and long-term outcome data are lacking. To better delineate the clinical nuances, complications, and outcomes of ruptured PICA aneurysms, we investigated in-hospital and long-term clinical data among a prospective cohort of SAH patients enrolled in a randomized trial and compared the characteristics, complications, and outcomes of ruptured PICA aneurysms with all other ruptured intracranial aneurysms.
Methods: The demographic information, in-hospital clinical characteristics, and long-term outcome of 472 SAH patients enrolled in a randomized trial were prospectively collected. Vasospasm data were collected retrospectively. The following data points were analyzed between PICA and non-PICA aneurysms: patient age; Hunt-Hess grade; Fisher grade; treatment modality (clip vs. coil); incidence of radiographic and symptomatic vasospasm; need for tracheostomy and PEG placement; mRS score at discharge, 1 year, and 3 years; and incidence of poor outcome (mRS > 2) at each time interval.
Results: Of 472 consecutive SAH patients enrolled in the BRAT, 22 (4.7%) harbored a ruptured PICA aneurysm. Nineteen patients were treated with a far lateral craniotomy and microsurgical clipping (one crossover from coiling), two patients were treated with endovascular coiling, and one patient died before treatment. When comparing PICA patients to all other SAH patients, there were no statistically significant differences in Hunt-Hess grade (3.0 ± 1.13 vs. 2.7 ± 1.09, P = 0.18), Fisher grade (2.8 ± 0.50 vs. 2.75 ± 0.55, P = 0.54), radiographic vasospasm (53% vs. 40%, P = 0.45), or symptomatic vasospasm (12% vs. 17%, P = 0.75). PICA patients had a higher incidence of lower cranial nerve dysfunction and higher rate of Trach/PEG placement compared with non-PICA aneurysm patients (50% vs. 17%, P = 0.0008). PICA patients had a significantly higher incidence of poor outcome at discharge (91% vs. 67%, P = 0.0064), 1-year (63% vs 27%, P = 0.0001) and 3-years (63% vs 32%, P = 0.0064).
Conclusions: In this prospective cohort, patients with ruptured PICA aneurysms had a similar rate of radiographic vasospasm and equivalent admission Fisher and Hunt-Hess scores, but poorer clinical outcome at discharge, 1 year, and 3 years when compared with the rest of the BRAT population. The PICA’s location at the medulla and the resultant high rate of lower cranial nerve dysfunction may play a role in this poor outcome.
