Microvascular anastomosis under 3D exoscope or endoscope magnification: A proof-of-concept study

Abstract

Background:Extracranial–intracranial bypass is a challenging procedure that requires special microsurgical skills and an operative microscope. The exoscope is a tool for neurosurgical visualization that provides view on a heads-up display similar to an endoscope, but positioned external to the operating field, like a microscope. The authors carried out a proof-of-concept study evaluating the feasibility and effectiveness of performing microvascular bypass using various new exoscopic tools.Methods:We evaluated microsurgical procedures using a three-dimensional (3D) endoscope, hands-free robotic automated positioning two-dimensional (2D) exoscope, and an ocular-free 3D exoscope, including surgical gauze knot tying, surgical glove cutting, placental vessel anastomoses, and rat vessel anastomoses. Image quality, effectiveness, and feasibility of each technique were compared among different visualization tools and to a standard operative microscope.Results:3D endoscopy produced relatively unsatisfactory resolution imaging. It was shown to be sufficient for knot tying and anastomosis of a placental artery, but was not suitable for anastomosis in rats. The 2D exoscope provided higher resolution imaging, but was not adequate for all maneuvers because of lack of depth perception. The 3D exoscope was shown to be functional to complete all maneuvers because of its depth perception and higher resolution.Conclusion:Depth perception and high resolution at highest magnification are required for microvascular bypass procedures. Execution of standard microanastomosis techniques was unsuccessful using 2D imaging modalities because of depth-perception-related constraints. Microvascular anastomosis is feasible under 3D exoscopic visualization; however, at highest magnification, the depth perception is inferior to that provided by a standard operative microscope, which impedes the procedure.

Otosurgery with the High-Definition Three-Dimensional (3D) Exoscope: Advantages and Disadvantages

“…Similarly, during tympanoplasty, we found that the microscope was more comfortable when removing the cholesteatoma or granulation tissue from the tympanic cavity and hidden areas of the middle ear (stages T6 and T7). Similar observations in microvascular bypass procedures have been reported [ 14 ]. As those studies have shown, microvascular anastomosis is feasible under 3D exoscope visualization; however, at the highest magnification, the depth perception is inferior to that provided by a standard operating microscope, which impedes the procedure [ 14 ].…”

Monitor-based exoscopic 3D4k neurosurgical interventions: a two-phase prospective-randomized clinical evaluation of a novel hybrid device

“…The utilization of a hybrid visualization system like the one investigated in this study can help adjust workflows and gain experience in more complex microneurosurgical tasks before switching to a standalone exoscope. Until completion of this paper, one other study on the same system has been published [ 4 ] presenting results of a comparative preclinical assessment of microvascular anastomosis. The authors conclude that the 3D4k exoscope allows for neurovascular task completion; however, in their evaluation, size and width of the field of view as well as sharpness and resolution at high magnification were still superior in ocular mode.…”

“…From the clinical perspective, this device evolution is designed to address current constraints in surgical access and ergonomics, digitally enhanced visualization and information sharing in the OR, all of which can have high impact on surgical interventions of varying complexity. Exoscope technology is trying to overcome previously experienced limitations in endoscopy and surgical microscopy [ 25 , 26 ] by merging these two major intraoperative visualization techniques [ 4 , 22 ] and seeking to establish new quality standards [ 4 ]. An exoscope is an extracorporeal scope [ 13 ] distanced from the surgical site, producing high-quality video images with a wide field of view [ 19 ].…”

Home Program for Acquisition and Maintenance of Microsurgical Skills During the Coronavirus Disease 2019 Outbreak

“…It has been previously shown that microsurgical performance under two-dimensional visualization is possible but requires more time and may be not so effective, compared with a three-dimensional visualization. 35 , 36 …”