Vitreoretinal instruments: vitrectomy cutters, endoillumination and wide-angle viewing systems

Abstract

There have been many advances in vitreoretinal surgery since Machemer introduced the concept of pars plana vitrectomy, in 1971. Of particular interest are the changes in the vitrectomy cutters, their fluidics interaction, the wide-angle viewing systems and the evolution of endoillumination through the past decade and notably in the last few years. The indications of 27-gauge surgery have expanded, including more complex cases. Cut rates of up to 16,000 cuts per minute are already available. New probe designs and pump technology have allowed duty cycle performances of near 100% and improved flow control. The smaller vitrectomy diameter can be positioned between narrow spaces, allowing membrane dissection and serving as a multifunctional instrument. Enhanced endoillumination safety can be achieved by changing the light source, adding light filters, increasing the working distance and understanding the potential interactions between light and vital dyes commonly used to stain the retina. Wide-angle viewing systems (contact, non-contact or a combination of both) provide a panoramic view of the retina. Non-contact systems are assistant-independent, while contact systems may be associated with better image resolution. This review will cover some current aspects on vitrectomy procedures, mainly assessing vitrectomy cutters, as well as the importance of endoillumination and the use of wide-angle viewing systems.Electronic supplementary materialThe online version of this article (doi:10.1186/s40942-016-0052-9) contains supplementary material, which is available to authorized users.

Tips, Tricks, and Advantages of 27-G Vitrectomy

“…In order to overcome Poiseuille's law, which states that the flow rate is affected by the decreased inner lumen diameter, next-generation cutters with a higher cut rate (7,500 cuts per min), higher vacuum settings (up to 650 mm Hg), and improved duty cycles were developed [3,4].…”

Real-life comparison of the viewing angle and the image quality of two commonly used viewing systems for vitreoretinal surgery

“…Although, the potential advantages, limitations, and drawbacks are anticipated theoretically or have been experienced subjectively, there has not been any quantitative real life comparison of the 2 major viewing approaches (contact versus noncontact) in vitreoretinal surgery. In addition, although variations in the theoretical viewing angle under different surgical conditions have been anticipated [2], this has remained an unstudied subject.…”

“…On the other hand, an inconvenience of the noncontact WAV systems is occasional fogging or condensation on the lens, which may result from suboptimal draping, a deepset eye, fluid accumulation at the medial canthus, or cold room temperature. This inconvenience may be overcome by additional precautions such as use of antifog solutions, careful draping, optimal positioning of the patient's head [2,15].…”

Retinal Toxicity of Medical Devices Used during Vitreoretinal Surgery: A Critical Overview

“…After years of technical refinement, the indications were widened for less severe pathologies and even elective cases such as membrane peeling as a possible treatment option for epiretinal membranes [3]. After further technical refinements [4,5], vitrectomy has become the second most common surgery in ophthalmology now covering emergency and elective indications [3,6]. During the surgical procedures, many factors that might harm the tissue are among others the use of excessive endoillumination [7], an irrigation solution with a different composition than the human vitreous [8], the suppression of blood flow [9], air infusion [10], drugs [11] and medical devices [12].…”