An anatomic study of superficial temporal artery to anterior cerebral artery bypass using ipsilateral parietal branch of superficial temporal artery as graft

Abstract

Objective Revascularization of the distal segment of the anterior cerebral artery (ACA) using extracranial donors requires long interposition grafts. A novel bypass procedure which uses the two main branches of the superficial temporal artery (STA) to reach the A3 segment of the anterior cerebral artery with a single skin incision was designed. Methods Ten cadaveric specimens were dissected through a single skin incision to harvest the frontal and parietal branches of the STA from June, 2017 to September, 2017. An anterior interhemispheric approach provided access to the middle internal frontal artery (MIFA). The parietal STA was used as an interposition graft between the frontal STA and MIFA. Lengths and calibers of the distal branches of STA and MIFA were measured at the anastomotic sites. All data was statistical analysis by t-test. Results The average caliber of MIFA was (1.4±0.2) mm, which matched the caliber of both frontal and parietal branches of STA. The mean distance for an end-to-side bypass from STA to MIFA was (144.5±7.4) mm and the average harvested donor-graft complex length was (203.1±27.9) mm. This bypass construct provided around 140% donor graft length. Conclusion Using the parietal branch of the STA as an interposition graft enabled a successful tension-free STA-MIFA bypass. The advantages of this technique over existing approaches include sufficient graft length, caliber match and relative technical ease. Key words: Anterior cerebral artery (ACA); Extracranial-intracranial bypass; Superficial temporal artery; Interhemispheric approach; Cerebral revascularization; Microsurgical anatomy