Neurosurgical applications of the exoscope: from in vitro studies to real-life surgical use in selective dorsal rhizotomy

Background

The microscope has been the gold standard in neurosurgical practice due to its ability to magnify anatomical structures. However, it has limitations, including restricted visual fields and ergonomic challenges that can lead to surgeon fatigue and musculoskeletal issues. The exoscope is an emerging technology that may address these limitations by offering comparable magnification with improved ergonomics.

Methods

This study compares the traditional microscope (KINEVO 900) with a 3D digital exoscope (Aeos Digital Microscope) in visual field width, image sharpness, and ergonomic impact. Visual field assessments were conducted using millimeter paper at a fixed distance, while image sharpness was evaluated using graph paper with pins at different depths. Ergonomic evaluation involved simulating surgical positions using a spine anatomical model. The practical applicability was tested during Selective Dorsal Rhizotomy (SDR) procedures, comparing the surgeon's experience with both devices over 20 consecutive cases.

Results

The exoscope provided a larger visual field (81.18 cm²) compared to the microscope's (54.10 cm²). Image sharpness was similar for both devices across various depths and zoom levels. Ergonomically, the exoscope allowed the surgeon to maintain a neutral posture while visualizing extreme angles, unlike the microscope, which required significant upper body movement. In SDR procedures, the exoscope improved surgeon comfort and interaction with the operating team, despite an initial learning curve.

Conclusions

The exoscope presents notable advantages in terms of visual field and ergonomics. The exoscope’s ability to facilitate better posture and team communication without compromising image quality makes it an addition to neurosurgical practice, as in SDR.