# Double-barrel STA-MCA bypass with endovascular parent artery occlusion for complex anterior circulation aneurysms: indications and outcomes

## TL;DR

A hybrid surgical and endovascular approach successfully treats complex brain aneurysms by combining bypass surgery with artery occlusion.

## Contribution

This study introduces a hybrid treatment combining double-barrel STA-MCA bypass with endovascular occlusion for complex intracranial aneurysms.

## Key findings

- All patients had successful aneurysm exclusion and preserved perfusion confirmed by postoperative DSA.
- No permanent neurological deficits or bypass failures were observed in the study group.
- Long-term follow-up showed complete aneurysm occlusion and maintained bypass patency in all patients.

## Abstract

To assess the long-term clinical outcomes of a hybrid approach combining double-barrel superficial temporal artery to middle cerebral artery (STA-MCA) bypass with endovascular parent artery occlusion in the treatment of giant complex intracranial aneurysms. This retrospective observational study included patients with giant or fusiform intracranial aneurysms who underwent double-barrel STA-MCA bypass followed by endovascular occlusion of the parent artery between January 2019 and January 2025. The primary outcomes were bypass patency, aneurysm exclusion, and ischaemic complications. Secondary outcomes included postoperative neurological status (assessed using the modified Rankin Scale [mRS]), radiological follow-up results, and procedural complications. Follow-up was conducted at 1-, 3-, and 6-month post-procedure and annually thereafter, including clinical assessment and imaging with MRI/MRA or DSA. Seven patients (mean age, 44.7 ± 27.5 years; 57.1% male) were included in the analysis. Most aneurysms were fusiform (85.7%) and located in the MCA (71.4%). All patients underwent double-barrel bypass and endovascular occlusion. Postoperative DSA confirmed aneurysm exclusion and preserved perfusion in all cases. No permanent neurological deficits or bypass failures were observed. One patient developed transient hemiparesis, which was resolved spontaneously without intervention. In one emergency case, a double-barrel bypass was performed following coil prolapse and occlusion of both M2 segments during endovascular embolization; the patient was discharged with mild residual contralateral paresis. At long-term follow-up, all aneurysms remained completely occluded, and bypass patency was maintained in all patients. In appropriately selected cases, a hybrid approach combining double-barrel STA-MCA bypass with endovascular parent artery occlusion offers a safe and effective treatment option for complex intracranial aneurysms. This strategy provides reliable flow restoration and durable aneurysm exclusion, particularly when performed in a hybrid operating setting.