Indocyanine green videoangiography for the identification of superficial temporal artery branches in EC-IC bypass surgery

Superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass remains an essential tool for managing complex cerebrovascular conditions. A crucial surgical step is the identification and safe dissection of the bypass donor artery. If the frontal branch of the STA is used, a curvilinear fronto-temporal scalp flap generally allows for a clean dissection from the underside of the scalp flap. This dissection is sometimes tedious, since the frontal branch is not always easily visible and due to variability of its anatomy. With this article, we report on the feasibility and effectiveness of a simple indocyanine green videoangiography (ICG-VA)-assisted technique for the identification of the STA branches from the underside of a fronto-temporal scalp flap in bypass surgery. The technique is based on the analysis of the difference in timing of filling of scalp vessels illuminated via ICG-VA from the underside of a scalp flap. Three illustrative cases are reported. ICG-VA permitted the correct identification and safe dissection of the donor vessels (STA branches) in all three patients. There were no complications due to the ICG-VA. This technique allows reliable visualization of the STA and its branches at once before microsurgical dissection. The information provided by ICG-VA enables precise mapping and preparation of the STA. The simplicity and safety of this technique make it an effective tool for intraoperative identification of the STA and its branches.