Treatment of Vertebral Artery Aneurysm with OA-PICA Bypass in the Prone Position

The occipital artery-posterior inferior cerebellar artery (OA-PICA) bypass is a well-known surgical technique for the treatment of vertebral artery (VA) aneurysms involving the PICA. However, the OA-PICA bypass is considered to be a difficult procedure owing to the deep operative field and the proximity of the lower cranial nerves. The mid-lateral suboccipital approach allows for the establishment of a wide and superficial operative field reliably and safely.