SURGICAL ACCESS TO THE THIRD SEGMENT OF THE VERTEBRAL ARTERY

Abstract

Today V3 is the rarest and most difficult to access segment of the vertebral artery (VA). Material and methods. A sectional study was performed in 35 patients who died from various causes to study the topographic and anatomical characteristics of the VA anatomy in V3. The technique of access to the VA: along the inner edge of the right sternocleidomastoid muscle, a linear incision 6.2+1.5 cm long was performed, starting from the level of 2.1+0.8 cm above the angle of the lower jaw along the submandibular fold towards the «tragus» auricle. The common carotid artery, the internal carotid artery (ICA), the jugular vein, and the external carotid artery up to the third segment were isolated with excision and ligation of the lateral branches. The dissection of the salivary gland was not carried out, since it is quite mobile and is well retracted by the retractor hooks, as well as the venous plexus, nerves, «digastric» muscle. Results. The original approach proposed by us suggests reducing surgical trauma, as well as reducing the risk of developing damage to the neurovascular structures in the intervention zone. When working on the sectional material, the distance between the distal portion of the ICA and the third segment of the VA was determined. It did not exceed, according to our data, 3.2+2.1 mm. This fact allows, if necessary, to safely form an anastomosis between the ICA and the VA in the V3 segment according to the «side-to-side» type. Conclusions. The proposed access to the third segment of the VA enables the reduction of surgical trauma by reducing the incision length up to 6.2+1.2 cm, as well as by mobilizing anatomical structures in the surgical wound without crossing them (salivary gland, jugular vein, vagus nerve, C2 - a portion of the brachial plexus, digastric muscle, internal carotid artery). With concomitant tortuosity of the ICA, the excess part of the ICA is the optimal material for bypassing the VA in the third segment of the VA. A variant of surgical correction in this situation is the formation of «trifurcation» of the carotid artery.