Comparison of Exoscopic and Microscopic Superficial Temporal Artery to Middle Cerebral Artery Bypass.

Purpose: Exoscopes have been used as a reliable surgical tool in the neurosurgical field. They could improve surgical field visibility with 4K three-dimensional (4K-3D) monitors and provide alleviation for the physical strain by allowing surgeons to maintain a neutral posture. In this study, we report our initial experience with exoscopic superficial temporal artery (STA)-middle cerebral artery (MCA) bypass compared to the conventional microscope at our institution.

Methods: This study included 58 patients with ischemic status, including internal carotid artery (ICA) stenosis, ICA occlusion, MCA stenosis, MCA occlusion, and moyamoya disease with ischemic onset, who underwent STA-MCA bypass between January 2021 and August 2022. The baseline characteristics, setup time, operative time, duration of MCA occlusion, surgical complications, and clinical outcomes were retrospectively analyzed. Additionally, a total of 19 neurosurgeons evaluated the effects of exoscope on the cerebrovascular procedure by using a questionnaire.

Results: 36 patients (62.0%) underwent the procedure with the use of an exoscope. The patient's characteristics were similar between the two groups. No significant differences in the setup time (74 min vs. 73 min), operative time (382 min vs. 385 min), surgical complications (2.8% vs. 4.5%), or favorable outcomes (100% vs. 95.5%) were observed between the two groups. In the postoperative questionnaire evaluation, the exoscope received higher scores in "image quality" (78.9%), "brightness" (84.2%), "operability" (73.7%), and "education" (57.9%). In contrast, the conventional microscope received higher scores in "assistant work" (73.7%).

Conclusion: The benefits of the exoscope were high image quality, an expanded view with digital zoom, and its compact body and comfortable resting position, which reduce the fatigue of neurosurgeons. On the basis of the findings of this study, the exoscope was found to be useful in STA-MCA bypass and demonstrated favorable outcomes comparable to those of the conventional microscope.