Occipital Artery and Its Segments in Vertebral Artery Revascularization Surgery: A Microsurgical Anatomic Study

To study the microsurgical anatomy of the occipital artery (OA) to determine the optimal segment for use as a conduit in revascularization bypass surgery. Twelve sides of 6 cadaveric heads that had been injected with colored silicone were exposed using C-shaped postauricular incision. The OA was dissected from its point of origin to the proximal part of the distal segment. For each segment, the diameters and length were measured, and its branches and proximity to the recipient vessel (V3) were examined. The mean diameters were 2.6 mm at the digastric segment, 2.04 mm at the point where it exits the mastoid sulcus, 2.0 mm, at the point just before the last descending muscular branch, and 1.8 mm and 1.5 mm after the branch and attached to the superior nuchal line, respectively. The length of the OA from the point where it exits the mastoid sulcus to the point at which it revealed the last descending muscular branch was 53 mm, and the distance of this section to the V3 was 31 mm. In pathologies necessitating vertebral artery revascularization surgery, it is possible to easily mobilize the OA with a C-shaped postauricular incision in the lateral suboccipital region. To reach a more appropriate segment in terms of diameter, length, and easy anastomosis, V3 sulcal and OA suboccipital segments are more suitable. Thus, if bypass surgery is indicated in cases of vertebrobasilar ischemia, the suboccipital segment of the OA may be an ideal choice and considered as an artery that can be used in “SOS” conditions. •The easiest release of the OA is in the suboccipital segment.•The diameter of the OA decreased to 1.8 mm immediately after giving off the descending muscular branch.•When the muscles forming the suboccipital triangle were removed, the part of V3 extending over the C1 transverse process was also revealed, and this segment of the VA was found to be very close to the suboccipital segment of the OA.•The venous plexus was most dense both in a dural segment of V3 and the area where the VA was adjacent to the jugular vein.•To reach the widest and the easily dissected segment of the OA and the sulcal part of V3, incision patterns extending under the mastoid are more suitable.