Simultaneous Clipping and Superficial Temporal Artery-Middle Cerebral Artery Bypass for Unruptured Middle Cerebral Artery Aneurysm Concomitant with Proximal Stenosis.

Management of unruptured intracranial aneurysms concomitant with proximal stenosis remains challenging. Video 1 demonstrates simultaneous clipping and superficial temporal artery (STA)-middle cerebral artery (MCA) bypass for unruptured MCA aneurysm concomitant with proximal stenosis. A 56-year-old man presented with paroxysmal left limb weakness for 2 years. Magnetic resonance angiography and digital subtraction angiography showed a right MCA bifurcation aneurysm concomitant with severity of proximal M1 stenosis. Arterial spin labeling imaging revealed decreased perfusion in the right frontal and parietal lobe. A frontotemporal craniotomy was performed, and the parietal branch of the STA was dissected as a donor artery.1-3 The MCA (M4) branch with the largest diameter was chosen as the recipient. STA-MCA bypass was performed using end-to-side anastomosis with interrupted 10-0 sutures. Next, the sylvian fissure was opened from distal to proximal dissection. The MCA bifurcation aneurysm with atherosclerosis of the M1 was exposed. A curved clip was used to occlude the aneurysm without temporary occlusion of the parent artery. The patient recovered well without any complications. Six-month follow-up angiography confirmed complete obliteration of the aneurysm and patent STA-MCA anastomosis. For unruptured MCA aneurysms concomitant with proximal stenosis, 1-stage surgical treatment with simultaneous clipping and STA-MCA bypass is a feasible alternative. Further studies are needed to compare the safety and efficacy of 1-stage surgical treatment and endovascular embolization of intracranial aneurysms concomitant with proximal stenosis.