Surgical treatment of complex posterior inferior cerebellar artery aneurysms using revascularization

Introduction. Posterior inferior cerebellar artery (PICA) aneurysms are rare (0.5–4.5 %) but are characterized by high mortality and treatment complexity. In cases of complex morphology, standard methods carry a risk of arterial occlusion, necessitating the use of revascularization techniques to preserve blood flow and perforator supply to the brainstem.

The aim. To present the results of microsurgical treatment of posterior inferior cerebellar artery aneurysms using various revascularization methods.

Materials and methods. Fourteen patients (mean age 52.2 years; 71.4 % female) were operated on during the acute, subacute, and delayed periods after subarachnoid hemorrhage and in the unruptured state. In 21.4 % of cases, previous endovascular treatment had been non-radical. Aneurysm size ranged from 4 to 20 mm (64.3 % – ordinary, 35.7 % – large); 50 % were partially thrombosed.

Results. Various types of anastomoses were employed: aneurysm resection + reanastomosis of the free ends of the PICA (28.7 %); aneurysm resection + reanastomosis of the free ends of the PICA + graft (7.1 %); aneurysm trapping with creation of a side-to-side anastomosis (42.8 %); aneurysm resection + reimplantation of the PICA into a new orifice of the V4 segment (7.1 %); and aneurysm resection + reimplantation into the contralateral PICA (14.3 %). Radical exclusion of the aneurysm and patency of the anastomoses were achieved in all patients. New neurological deficit (cranial nerve dysfunction) was observed in 14.3 %. There were no ischemic strokes, complications, or fatalities. The mean hospital stay was 7.6 days.

Conclusion. Microsurgical treatment of complex PICA aneurysms with revascularization ensures radical aneurysm exclusion with preservation of blood flow. Both extra-intracranial and intra-intracranial microvascular anastomoses can be employed.

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