gms | German Medical Science

Objective: Since the 1970s, the operating microscope (OM) is standard for visualization and illumination of the surgical field in spinal microsurgery. However, due to its limitations (e.g. size, high costs and limited movability of binocular lenses with uncomfortable surgeons’ posture), there are efforts to replace the OM by exoscopic video-telescopes. We evaluated the feasibility of a new 3D exoscope (3D-E) as an alternative to the OM in spine surgeries.

Methods: Patients with single-level degenerative pathologies undergoing lumbar or cervical spinal surgery were enrolled from 01-09/2019 in a prospective cohort study for use of a 3D-E. Age-, sex-, and procedure-matched patients with use of the OM served as control group. Operative baseline and postop. outcome parameters were assessed. Periprocedural handling, visualization and illumination by the exoscope, as well as surgeons’ comfort level of posture were scored via a questionnaire.

Results: 40 patients undergoing lumbar posterior decompression (LPD) and 20 patients undergoing anterior cervical discectomy and fusion (ACDF) with a 3D exoscope were studied with an equal number of controls using OM. Compared to controls, there were no significant differences for mean operation time (LPD: 112 vs. 108min.; p=0.58 / ACDF: 131 vs. 119 min.; p=0.26) and blood loss (p=0.95). The same was true for postop. improvement of symptoms (neck disability index: p=0.43 / Oswestry disability index: p=0.76) and median length of hospital stay (LPD: 6 vs. 6 days; p=0.60 / ACDF: 5 vs. 6 days; p=0.23). There were no intraoperative complications during 3D exoscope procedures. According to the attending surgeon, the intraoperative handling of instruments was rated to be comparable to the OM, while comfort level of the intraoperative posture (esp. during "undercutting" procedures) was assessed to be superior. Esp. in case of ACDF procedures and long approaches, depth perception, image quality, and illumination were rated to be inferior compared to the OM. By contrast, for non-surgical staff participating in 3D exoscope procedures, the visualization of intraoperative process flow and surgical situs was rated to be superior compared to the OM, esp. for ACDF procedures.

Conclusion: A 3D exoscope seems to be a safe alternative for common spinal decompressive procedures with the unique advantage of excellent comfort for the surgical team, but the drawback of still slightly minor visualization/illumination quality compared to the OM.