1. Preoperative cerebral angiography should be carefully analyzed for PICA aneurysm angioarchitecture evaluation and surgical planning
2. IC-IC bypass was the first choice because remote donor artery or graft harvesting is unnecessary, and IC-IC bypass provides better dural closure.
3. The far lateral approach was appropriate for proximal PICA aneurysms.
4. PICA-V4 reimplantation was appropriate for proximal PICA aneurysm with PICA originating high from the VA superior and inferior to the hypoglossal nerves.
5. Intraoperative electrophysiological monitoring is essential for brainstem ischemia warning.
6. Dentate ligament transection is essential to decrease the interference of the lower cranial nerves in aneurysm access.
7. Meticulous and skilled deep bypass techniques are critical for safe bypass surgery.
8. During the bypass, we used Prolene 10-0 sutures. We first placed an anchor suture at the distal corner of the anastomotic stoma. Then, an opposite anchor suture was placed. Interrupted sutures were used.
9. Considering the thickness of the VA intima, interrupted sutures should be used to sew up both the intima and adventitia to avoid artery dissection formation.
10. A Doppler probe, intraoperative indocyanine green, and even angiography should be applied to assess the aneurysm obliteration and bypass patency.
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Zixiao Yang and Jianping Song are the first two authors contributed equally to this work.
This article is part of the Topical Collection on Vascular Neurosurgery - Aneurysm