Spontaneous thrombosis of giant dissecting fusiform middle cerebral aneurysm following double-barrel superficial temporal artery – middle cerebral artery bypass: A case report of decision-making in limited resource environment.

Abstract Background The treatment of giant fusiform middle cerebral artery (MCA) aneurysms remains daunting due to their tendency to be associated with precarious end-vessel anatomy and need for complex microsurgical techniques to appropriately address the aneurysm and the vasculature at risk. Extracranial-intracranial (EC-IC) bypass revascularization remains a valuable tool for treating these complex lesions. Here, we report a rare occurrence in which the creation of double-barrel superficial temporal artery–middle cerebral artery (STA-MCA) bypass facilitated spontaneous obliteration of the aneurysm. We highlighted our decision-making impacted by operating in a low middle-income country with limited resources. Case description A 32-year-old man presented with recurrent ischemic events in the left MCA distribution and subsequent subarachnoid hemorrhage due to rupture of a giant complex fusiform MCA aneurysm. The patient was treated with a double barrel STA-MCA bypass and planned for second-staged clip reconstruction or partial trapping. Postoperative imaging revealed progressive thrombosis of the M1 segment resulting in occlusion of the aneurysm without subsequent trapping/clipping. The patient recovered remarkably without further re-hemorrhage or ischemic injury. A literature review is presented. Conclusion Double barrel STA-MCA bypass is a potential salvage surgical technique to treat selected ruptured complex giant fusiform MCA aneurysms. In rare selected cases, the flow alteration induced by the bypass alone can potentially facilitate aneurysm thrombosis.