Immediate and long-term outcomes of microsurgical treatment for patients with aneurysms of the posterior inferior cerebellar artery in the acute stage of subarachnoid hemorrhage

Introduction. Aneurysms of the posterior inferior cerebellar artery (PICA) account for approximately 0.36–4.5 % of all intracranial aneurysms. The rupture rate reaches 77–88 %, and the risk of rerupture is 71–78 %. Currently, microsurgical and endovascular treatment methods are competing. However, despite their advantages, endovascular interventions for ruptured aneurysms have a number of drawbacks. According to modern protocols, the treatment of choice for excluding PICA aneurysms from the circulation in the acute period of subarachnoid hemorrhage (SAH) is microsurgical clipping.

The aim of this study. To evaluate the immediate and long-term outcomes, as well as the quality of life and return to work after microsurgical treatment of PICA aneurysms in the acute stage of SAH.

Materials and methods. A retrospective study included 32 patients operated on in the acute stage of SAH at the Moscow Regional Research and Clinical Institute from June 2019 to December 2024.

Results. Patients admitted to the hospital in a compensated state (13–15 points on the Glasgow Coma Scale (GCS), Grade 1 and 2 on the Hunt – Hess scale) showed favorable clinical outcomes after treatment (mean Glasgow Outcome Scale (GOS) score – 7.4). Favorable clinical outcomes were also noted among decompensated patients (9–12 points on the GCS, Grade 3 and 4 on the Hunt – Hess scale) (mean GOS score – 6.9). Mortality was 6.2 % (n = 2). Distribution of patients according to the EQ-5D-3L health questionnaire: full recovery – 15 (55.7 %), good recovery – 7 (25.9 %), other patients – 5 (18.5 %). According to the patients’ subjective assessment of their health status, the mean value was 79.8 ± 12.9 points. Twenty patients (74.1 %) returned to work.

Conclusion. Microsurgical treatment of PICA aneurysms is a safe and effective method with favorable immediate and long-term outcomes. Good quality of life and return to work were observed in more than 74% of patients.

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