Surgical Tips for STA-MCA Bypass from Misato Central General Hospital

Superficial temporal artery to middle cerebral artery (STA-MCA) bypass is an essential technique, not just for treating cerebral ischemia but also for assisting aneurysm clipping and compensating for unexpected vascular injuries during surgery.Although it is becoming a more fundamental surgery technique because of the provision of off-the-job training, there are several points that should be considered to achieve successful anastomosis. In this article, we describe important points and tips to consider during STA-MCA bypass.To perform a successful anastomosis, it is important to ensure the following: (1) creation of an operative view without blood and cerebrospinal fluid, (2) selection of a suitable recipient artery, and (3) prevention of anastomosis occlusion.A recipient artery that runs downward from right to left (when the operator is right-handed) is considered suitable because of easier needle handling while suturing. Suturing the backside and inversion of the anastomosis should be avoided to prevent anastomosis occlusion. To avoid suturing the backside, we perform an oval arteriotomy on the recipient artery instead of a linear incision. Furthermore, difficult anastomosis is prioritized, and stay sutures and bilateral sutures are performed by the marked pin method and T-junction bypass when anastomosing in part with a large-diameter branch. To avoid inversion, we require the stitch interval of the donor and recipient arteries to be at a ratio of 6:4. We also tie a knot by pulling the thread from the donor side, which ensures that the inner membranes are attached together.Anastomosis is the most important procedure because the ultimate goal of this operation is to prevent cerebral ischemia by achieving long-term patency. The technique should be unified and simplified so that it is available for even young neurosurgeons.The techniques we have introduced are not difficult or complicated, although they can only be put into practice after acquiring the basic skills. Therefore, young neurosurgeons must continue training and preparing for surgeries.