Tailored Communicating Bypass for the Management of Complex Anterior Communicating Artery Aneurysms: "Flow-Counteraction" In Situ Bypass and Interposition Bypass Using Contralateral A2 Orifice as Donor Site.

ABSTRACT

BACKGROUND: The use of bypass surgery for anterior communicating artery (ACOM) aneurysms is technically challenging. Communicating bypass (COMB), such as pericallosal artery side-to-side anastomosis, is the most frequently used and anatomically directed reconstruction option. However, in many complex cases, this technique may not afford a sufficient blood supply or necessitate sacrificing the ACOM and the eloquent perforators arising from it. OBJECTIVE: To evaluate tailored COMB and propose a practical algorithm for the management of complex ACOM aneurysms. METHODS: For 1 patient with an aneurysm incorporating the entire ACOM, conventional in Situ A3-A3 bypass was performed as the sole treatment in order to create competing flow for aneurysm obliteration, sparing the sacrifice of eloquent perforators. In situations in which A2s were asymmetric in the other case, the contralateral A2 orifice was selected as the donor site to provide adequate blood flow by employing a short segment of the interposition graft. RESULTS: The aneurysm was not visualized in patients with in Situ A3-A3 bypass because of the "flow-counteraction" strategy. The second patient, who underwent implementation of the contralateral A2 orifice for ipsilateral A3 interposition bypass, demonstrated sufficient bypass patency and complete obliteration of the aneurysm. CONCLUSION: The feasibility of conventional COMB combined with complete trapping may only be constrained to selected ideal cases for the treatment of complex ACOM aneurysms. Innovative modifications should be designed in order to create individualized strategies for each patient because of the complexity of hemodynamics and the vascular architecture. Flow-counteraction in Situ bypass and interposition bypass using the contralateral A2 orifice as the donor site are 2 novel modalities for optimizing the advantages and broadening the applications of COMB for the treatment of complex ACOM aneurysms.