This decade has seen major advances in vitreoretinal surgery. These innovations encompass pre-operative imaging, pre-operative pharmacotherapy, intraoperative fluidics, high-speed cutting, advanced cutter designs, improved illumination, digital microscopic viewing, tissue identification, micro instrumentation, and, ultimately, postoperative improvements in patient care that enhance surgical outcomes including shortened positional requirements and pharmacotherapy.

These advances have been predominantly incremental in their development; however, taken in their entirety, they have markedly improved both anatomic and visual outcomes while extending our surgical indications to previously untreatable retinal disease. Nonetheless, these changes have revolutionized our patients’ experiences with us.¹

These patient’s first clinical interaction is often with an ophthalmic technician or assistant both prior to a surgical decision and in postoperative care. Their understanding of a patient’s experience in the operating room is critical to their ability to provide an evaluation and counseling.

What follows is an update on the latest advancements in retinal surgery.

Vitrectomy

Three major changes have continued to evolve and enhance both the safety and efficacy of vitrectomy surgery.² Outside of the United States, patients with any degree of cataract who require vitrectomy typically have combined vitrectomy/phacoemulsification and IOL placement. This has rarely been the case in the United States. However, virtually every vitrectomy platform will soon be integrated with components that enable vitrectomy surgery, cataract surgery, or the combination of these two procedures.

From the cutting side during vitrectomy, we see a continued evolution to smaller gauge surgery that takes advantage of higher speed cutting and novel cutter configurations.^3,4 The focus of increasing cutting speeds is to minimize the impact of the cutter on surrounding tissues, thus limiting the likelihood of self-induced, or iatrogenic, complications such as retinal tear (Figure 1). Initially it was felt that high-speed cutting would plateau at a point where faster cutting would not be advantageous. However, for our current technologies with cutting speeds up to 20,000 cuts per minute, we have not experienced a decline in performance.⁵ Theoretically, higher speed cutting has the potential to minimize tractional forces both near and distant from the cutting port, but this may come with limitations in the flow through the cutter port, making the procedure longer.⁶

Another cutter innovation is the use of beveling at the cutter tip. This enables the cutter to function as a tissue manipulator, which allows for better development of a surgical plane in complex disease. Supporting this has been the shift of the cutting port distally bringing our cutter into closer proximity to the tissue to be cut. Small changes in the cutter design have had major impact on surgery.

The third major change has been toward smaller gauge vitrectomy. 23 gauge is now the “large” gauge for surgery with shifting approaches to both 25- and 27-gauge technology.⁷ For those of us who continue with 23-gauge surgery, a mixed gauge approach can enable the comfort of 23 gauge with the enhancement of 25 or 27 gauge for complex macular pathology (Figure 2).⁸ I have found mixed gauge surgery to be an excellent transitional step to smaller-gauge surgical management. For vitrectomy, wound healing at the sclerotomy site is clearly enhanced by smaller-gauge instruments. As for advanced high-speed cutting, small instruments have the downside of slowing overall surgery. From this perspective, mixed gauge surgery is ideal but typically impractical due to increased cost related to using two different “kits” for a single case (one for each gauge).⁹

A major advance that has benefited small gauge surgery — especially mixed-gauge surgery — is the ubiquitous institution of valved cannulas. The incorporation of valved technology has improved our control of the eye pressure during surgery, virtually eliminating the large fluctuations that may damage the eye from low pressure associated with bleeding and high pressure associated with optic nerve or blood vessel damage.¹⁰ Further, advanced cutting instruments have decreased the need for instrument changes to a single function scissor or forceps. Nonetheless, the cannulas that we now use routinely have made any needed instrument changes much safer for the eye. The downside to cannulas in general, and valved cannulas in particular, is the difficulty of extracting tissue from within the eye as is necessary for tumor biopsy. This is easily managed by using specific biopsy approaches or, where necessary, removing a single cannula to allow direct scleral access.

Ultimately, the use of small-gauge, valved cannula, and advanced cutters has led to sutureless surgery, which improves patient comfort. Valved cannula surgery and advanced tracers also have decreased iatrogenic trauma, which equates to lower re-operation rates and improved outcomes across the board for our patients. This is a major discussion point for our ophthalmic techs/assistants as patients talk with the office team and look for both knowledge and reassurance.

Visualization

Via illumination

Surgical field illumination is critical to any surgical endeavor. Improved illumination systems, integrated within our surgical platforms, have greatly improved visualization without increasing photic trauma. In fact, with the advance of digital microscopic imaging, light intensities have decreased dramatically without compromising viewing.^11-13

I have taught the importance of “lead with your view” as a staple in vitreoretinal surgery. A key component to visualizing complex pathology is illumination of the surgical field. Advances in viewing systems coupled with advanced lighting systems have enabled excellent visualization of the entire retina and anterior structures.

The importance of seeing our instruments and the anatomic pathology at the same time cannot be overstated. In Europe, as in several US-based practices, a special indirect illumination system that is inserted into the eye but does not require a hand to hold or manipulate is used for complex surgery. This indirect chandelier illumination is preferred when two-handed surgery is necessary or when the pathology is in the far retinal periphery. Current vitrectomy platforms have multiple available light sources within a single surgical platform that make this easy to incorporate into our practices.¹⁴

Via dye-based staining

For surgery, the use of injected dyes to highlight tissue has been a game-changer. Typically, these tissues are adherent to the retina, distort the retina and cause leakage or edema. Removal of the internal limiting membrane (ILM) was fraught with complications. But, with the use of staining dyes, this has become common place. Two dyes in use, indocyanine green (ICG) or tissue blue (Trypan blue), both stain the ILM well. The use of these dyes has enhanced closure rate for macular hole and decreased the recurrence for epiretinal membrane, and have improved outcomes for our patients. This understanding of ILM and its surgical manipulation have led to extending surgical management for patients with myopic and/or tractional macular retinoschisis.

Via digital imaging

Though traditional optical microscopic viewing remains the prevalent standard, the recent introduction of digital imaging using 3D imaging has greatly altered the operative theater environment especially within surgical teaching programs. Digital viewing of vitreoretinal surgery has the capacity to reduce lighting requirements for vitrectomy, allow filtering to enhance tissue planes without staining, maintain broader intraocular confocality during vitrectomy, and enhance depth of field without compromising magnification.

Early digital systems were limited by computer processing technology for high-resolution, large screen monitors, but current systems provide an excellent alternative to standard optical viewing. Using a digital viewing system assures a single view for both the primary and secondary surgeon but also incorporates the entire surgical team into the procedure.

From a teaching perspective this is a game-changer and has the potential to enable remote teaching/supervision. Additionally, these systems capture superb high-resolution surgical video with relative ease, thereby enhancing surgical case conferences and targeted training.

Recent advances have incorporated military technology that shifts the viewing to a helmet that is worn during surgery. Of note, for the F-35 fighter, the helmet is custom designed for the pilot and costs upward of $400,000 per helmet.

Single-use instruments

Further, the transition from surgical re-usable micro-instrumentation to single-use, disposable instruments has eliminated the concern for dysfunction of micro-instruments while allowing a broader selection of surgical tools (Figure 3). Ergonomics for actuation, enhancement of closure, use of texture, and broad availability through a variety gauges (23, 25, and 27) provide an excellent spectrum of instruments for virtually every known surgical maneuver. Again, this shift enhances our surgical abilities by always having sterile first-use instruments that do not require micro-surgical servicing or sterilization.

Imaging advances

From the tech and assistant perspective, advances in clinical imaging play a singularly major role for our patients. Many offices now use their techs to obtain color and OCT imaging, shifting the focus from a dedicated photographer. Fortunately, imaging technology has become easier to use while improving image capture and quality.

In this setting, advanced pre-operative and intra-operative imaging enable better surgical planning using swept-source OCT, widefield fundus photography and widefield FA/ICG angiography. Preoperative findings may predict both anatomic and visual outcomes for our patients. Intra-operative OCT continues to advance and is targeted toward assisting in complex pathology assessment during vitreoretinal surgery in a real-time application. The ability to confirm that the posterior hyaloid has been detached, that the epiretinal membrane has been peeled, that the transvitreal needle is in the subretinal space, or that ILM is absent may be critical decision points in complex surgical management.

Assuring our patients by including them in the review of images is an important aspect of our practice. Furthermore, imaging allows for ongoing learning for our patients and the clinical team.

Conclusion

Advances in instrumentation for vitreoretinal surgery now enable enhanced risk-benefit discussions for our patients while improving all aspects of surgical care. Surgical procedures are safer, recovery times are faster, and surgeons have an improved toolbox to enhance and improve their skill sets. Improved outcomes enable broader surgical applications while better documenting the procedure performed.

This is a unique time for the ophthalmic technician and assistant as their role in clinic expands to include advances in surgery. The importance of understanding these advances, and the ability to discuss them with our patients, is often critical to reduce both general anxiety and specific pre-operative concerns. Within the next year, we may even see next-generation vitrectomy platforms that incorporate these and other advances and truly enable our surgical field to continue to deliver the anatomic and visual outcomes that our patients, and our peers, have come to expect. OP

For references, see the online version of this article.