Bypass for Cerebral Aneurysms

Abstract

Introduction & Objective: The management of complex and giant aneurysm is problematic because of the wide atheromatous neck, involved branches, thrombus within, calcified wall, complex anatomy and eloquent surrounding.  Yet they need treatment as left alone, the prognosis is dismal. A retrospective analysis of complex aneurysms requiring microsurgical cerebral revascularization by a single surgeon in a single institution is presented. Material and Method: There were 49 Bypasses for complex cerebral aneurysms performed by the senior author between 1996 – 2022 at P D Hinduja Hospital & Medical Research Centre, Mumbai. There were 31 male and 18 female patients. Majority of the patients had giant aneurysms. The commonest presentation was with mass effect in 27. Nineteen patients presented with chronic headache and 3 presented with haemorrhage. The location of the aneurysm was infraclinoid ICA, supraclinoid ICA and MCA in 36, 8 and 5 respectively. Results: Extracranial to Intracranial (ECIC) Bypasses were 46, high flow 30 and low flow 16.  The high flow bypasses were External Carotid Artery (ECA) to Middle Cerebra Artery (M2) by radial artery graft in 29 and saphenous vein graft in 1.  The low flow bypasses were all superficial temporal to middle cerebral (STMC) anastomoses.  Three patients had in situ revascularisation. The bypass patency was 94 percent.  Two patients had infarct in the vascular territory in spite of patent bypass, one of which went for decompressive craniotomy, survived with deficit. There were 2 deaths (4%).  The 3^rd patient in the series died of sepsis and the 43^rd patient died of cerebral infarction in the post-operative period. Conclusions: In spite of recent advances in the endovascular therapy, a number of patients with complex and giant aneurysms are better served by cerebral bypass. Bypass is a low risk procedure with excellent outcome and hence young neurosurgeons need to train in lab for the same.