As a long-time proponent of endoscopy in retinal surgery, I’m often asked why I consider an endoscope so important, given that surgeons have historically performed vitreoretinal procedures successfully without these devices. My answer is that we all know the misery of unexpectedly losing good visualization during a procedure, and an endoscope essentially eliminates that concern. We owe it to ourselves and our patients to adopt technology that has the potential to reduce surgical time and complications.
The endoscope serves a function similar to the cameras on a car—it provides additional views that are not normally available. Once considered a nice-to-have tool, endoscopes are moving into the need-to-have category as appreciation of their utility in both challenging and routine retina surgical cases grows. Here are some of the main reasons retina surgeons should have access to an endoscope.
OPTIMAL VISUALIZATION
Endoscopy solves one of the biggest challenges in retina surgery—the loss of visualization during a case. Optimal visualization is vital to achieving good surgical outcomes. When applying laser for a retinal detachment or performing air-fluid exchange, visualization is improved dramatically with an endoscopic view. Additionally, in my experience, removal of perfluorocarbon liquid is greatly facilitated with the use of an endoscope, especially when replacing it with silicone oil, as it reduces the likelihood of leaving residual perfluoron behind. The endoscope can bypass anterior segment opacities and enhance visualization of anterior structures that may not be visible through a standard operating microscope. With the endoscope, the visibility requirement is normally 1 mm as compared with the operating microscope, which requires good visibility of the entire eye to view the retina (Figure 1). I find the panoramic view of anatomy and pathology made possible by the endoscope to be indispensable.
EFFICIENCY IN SURGERY
Working with an endoscope reduces surgical time by enabling completion of the procedure without excessive maneuvering.1 Problems like a sudden loss of pupillary dilation, presence of anterior or posterior capsule opacity, air entry into the anterior chamber, or corneal edema in prolonged surgical cases can be addressed with a standard operating microscope, but correcting such complications without an endoscope can extend surgical time and can compromise completion of posterior procedures.2
The Endo Optiks 23-gauge micro-endoscope that I currently use (BVI) allows me to work without a secondary light pipe. This multifunctional device combines endoscopy, light, and laser. The smaller gauge provides similar benefits to the larger 20-gauge probe that I previously used, but with the added advantage of smaller incisions. Heads-up 3-D surgical technology, which I use for every procedure, adds the benefit of enhanced ergonomics.
The endoscope is particularly efficient in cases involving the repair of primary or recurrent retinal detachments, which often have the greatest variability in visualization. Ocular maneuvers such as air-fluid exchange, peripheral membrane peeling, or inferior retinectomy can often cause a reduction in clarity. In some cases, the time spent in restoring sufficient visualization can take as long as the primary surgical objective. The endoscope allows for complete air-fluid exchange, endolaser application without scleral depression, retinectomy, and peripheral membrane peeling without prolonging the case (Figures 2 and 3).
CONCOMITANT GLAUCOMA TREATMENT
Endoscopy has allowed me to expand the scope of my practice in terms of managing multiple diseases simultaneously. I now can simultaneously treat surgical retinal diseases and glaucoma during routine or complex vitrectomy cases. Many patients with vitreoretinal diseases also have glaucoma. This relationship has increased in the last 19 years with the prolific use of intravitreal injections. In many patients their glaucoma is either controlled with medications or glaucoma surgery is being considered. In some patients, however, the glaucoma remains uncontrolled and future glaucoma surgery is already planned. These patients benefit the most from having endoscopic cyclophotocoagulation done at the time of vitrectomy (Figure 4).
OPACIFIED CORNEA AND KERATOPROTHESIS
When there is limited corneal clarity, an endoscope allows treatment of posterior and anterior segment pathologies. This is particularly beneficial when corneal opacification, hyphema with corneal blood staining, or other pathologies cloud the view. Using the endoscope for complex cases, such as opacified cornea or keratoprothesis, requires that you first have extensive experience—or at least some experience—in eyes that have clear visibility. Routine surgical cases will allow you to learn correct orientation and position of the endoscope within the eye, as well as basic maneuvers such as endolaser application.
As with any new technology, it makes sense to become comfortable using the endoscope in cases where it is not essential. This strategy describes my early experience with endophthalmitis vitrectomy cases. As I gained experience using the endoscope in these cases, I grew to appreciate the true potential of this technology. Begin by looking in the eye and learning how to orient the device correctly. It is important at this stage to develop a technique to securely handle the device so that it becomes second nature to use the endoscope during complicated cases. The learning curve is not steep; most surgeons become comfortable using the endoscope after only 5 cases.
SCLERAL FIXED IOL CASES
Many of the new intraocular lens (IOL) rescue or secondary IOL techniques involve the placement of IOLs in the sulcus or posterior to the iris. In many of these techniques, a leading cause of failure occurs due to malpositioning of the haptics. This malpositioning can be evaluated and corrected easily during surgery using the endoscope, and might otherwise not be discovered until postsurgical issues manifest. I have experienced this advantage many times in cases of uveitis-glaucoma-hyphema (UGH) syndrome, with chronic ocular inflammation or recurrent vitreous hemorrhage. The endoscope allows me to examine the posterior iris, sulcus, ciliary body, and pars plana for areas of haptic-induced trauma or neovascularization, with immediate treatment, if necessary.
Chronic haptic abrading of the structures in the sulcus has been identified using the endoscope and corrected with laser and haptic repositioning. (Figure 5). Although not my preferred technique, the endoscope can confirm correct suture location and haptic position in cases of sutured IOLs. Endoscopic assisted sutured IOLs with visual confirmation of suture and IOL location have been demonstrated to have a high rate of success and limited complications.3
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Although most retina practices have not yet adopted this technology, the benefits of retinal endoscopy are becoming increasingly clear. Young retinal surgeons will be pivotal in moving the specialty forward by lobbying for this device in their practices. NRP
REFERENCES
- Wong SC, Lee TC, Heier JS, Ho AC. Endoscopic vitrectomy. Curr Opin Ophthalmol. 2014;25(3):195-206. doi:10.1097/ICU.0000000000000052
- Rachitskaya A, Fisher YL. Endoscopy for vitreoretinal surgeons. American Academy of Ophthalmology. June 2013. Accessed June 1, 2023. https://www.aao.org/eyenet/article/endoscopy-vitreoretinal-surgeons
- Sugiura T, Sakimoto T, Tanaka Y, Inoue Y, Oshika T. Long-term outcomes of transsclerally sutured intraocular lens correctly fixed in the ciliary sulcus. BMJ Open Ophthalmol. 2022;7(1):e000935. doi:10.1136/bmjophth-2021-000935