Abstract
To minimize the temporary occlusion time during bypass surgery, continuous absorbable sutures with 9-0 polydioxanone (PDS) were employed in the superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses. Two cases of internal carotid artery occlusion and 4 cases of its stenosis were operated on in the chronic stage, and one case of MCA occlusion in the superacute stage. In all cases, a cold xenon-enhanced CT revealed the reduction of local cerebral blood flow (LCBF) preoperatively. Postoperative courses were uneventful and there were no anastomotic complications. The follow-up period ranged from 6 to 14 months. In 5 of the 6 cases in the chronic stage, all STAs and anastomotic sites grew remarkably in diameter 3 months after the surgery, when PDS had already lost tensile strength, and thereafter gradually increased in size. These changes were correlated with the improvement of LCBF. In the remaining one in the chronic stage, the STA showed less growing due to increased collateral flow via the external carotid artery system. In the case of MCA occlusion, growing of STA did not occur due to the low bypass-flow that resulted from the spontaneous recanalization of the occluded MCA. Previous studies suggested that absorbable PDS does not elicit inflammatory response, wall thickening, hyalinoid degeneration or calcification, which occasionally occur in use of nonabsorbable polypropylene sutures. In conclusion, PDS seems to be suitable for anastomosing small vessels and continuous PDS sutures are available for extracranial-intracranial arterial bypass surgery in which anastomotic sites grow corresponding to the increases of the bypass-flow.
