Exoscopic Keyhole Clipping of Unruptured Middle Cerebral Artery Aneurysms Using Multiple 4K 3-dimensional Monitors

We aimed to report our experience with exoscopic keyhole clipping of unruptured middle cerebral artery aneurysms using multiple 4K 3-dimensional monitors.We performed sphenoid ridge keyhole clipping of unruptured middle cerebral artery aneurysms using the ORBEYE exoscope (Sony Olympus Medical Solutions, Inc., Tokyo, Japan) with multiple 4K 3-dimensional monitors in 19 patients in our institution from 2020 to 2023. A 55-inch monitor was placed facing the surgeon at the end of an imaginary line extending through the Sylvian fissure ipsilateral to the target aneurysm. Two 32-inch movable sub-monitors were placed facing the surgeon at 45° angles to the left and right. Comparisons were made with a historical control group that comprised 21 patients who underwent the same procedure as above from 2017 to 2019 but with a surgical microscope rather than an exoscope.All exoscope group procedures were successfully accomplished using ORBEYE alone. Mean aneurysm diameter, craniotomy size, duration of intradural procedure, blood loss volume, and times of indocyanine green video angiography were similar in the exoscope and microscope groups. The mean indocyanine green dose was significantly lower in the exoscope group.Keyhole clipping for unruptured middle cerebral artery aneurysms using an exoscope and multiple 4K 3-dimensional monitors was safe and efficient, and not inferior to using a surgical microscope, suggesting that there are no major barriers for neurosurgeons to switch from microscopic to exoscopic keyhole clipping.