Comparative Evaluation of 3-Dimensional High Definition and 2-Dimensional 4-K Ultra-High Definition Endoscopy Systems in Endonasal Skull Base Surgery

BACKGROUND: The differences between 3-dimensional (3D) high definition (HD) and 2-dimensional (2D) 4-K ultra-HD (4K) endoscopy and their respective advantages remain unclear. OBJECTIVE: To evaluate the utility of these endoscopy systems in endonasal skull base surgery. METHODS: Consecutive series of endoscopic endonasal surgeries performed after introduction of 3D/HD and 2D/4K systems (July 2017) were retrospectively evaluated. Sporadic cases treated with either system, or a conventional 2D standard definition (SD) system, during the rental period from March 2016 were also included. Objective comparisons between the systems were made for newly diagnosed Knosp grade 0 to 3 pituitary adenomas. Surgical procedures were divided into nasal, sphenoidal, and intradural phases, and the surgical procedural time was compared for each phase. The time required for and accuracy of suturing the sellar floor dura was also evaluated. RESULTS: A total of 74 cases were treated with 3D/HD and/or 2D/4K, and 12 cases with 2D/SD. 3D/HD was advantageous in the nasal phase because of its intuitive depth perception. 2D/4K was advantageous in the intradural phase because of its superior image quality. Surgical time of the nasal phase with 3D/HD, and that of the intradural phase with 2D/4K, were significantly shorter than that with 2D/SD. The time required for and accuracy of sellar floor dural suturing showed a trend toward improving in the order of 2D/SD, 2D/4K, and 3D/HD. CONCLUSION: 3D/HD and 2D/4K endoscopy systems have different advantages, which are useful in distinct surgical phases. Understanding the characteristics of endoscopy systems is important for selecting the most appropriate system for distinct surgical situations.