Vajzovic, Lejla

When encountering diseases of the anterior vitreous and peripheral retina (ie, the “middle segment” of the eye), vitreoretinal (VR) surgeons are specifically trained in surgical techniques for managing the vitreous and visualizing the peripheral retina during anterior vitrectomy, and therefore, they are well equipped to address the complications of surgery involving the anterior vitreous space. This clinical update reviews and compares the current literature discussing techniques and patient outcomes related to complete pars plana vitrectomy versus incomplete, subtotal pars plana vitrectomy, and addresses the proposition of developing an abridged training curriculum for non-VR surgeons to acquire the knowledge and skills required to perform these procedures. Recent studies confirmed that operating in the anterior vitreous carries potential risk of retinal tear, retinal detachment, and other adverse events that may cause vision loss. To mitigate these risks, studies suggest that the use of dedicated visualization equipment and illumination instruments is necessary for surgeons to safely perform anterior vitrectomy and recognize complications, should any occur. Performing VR surgery in the absence of wide-angle viewing systems, endoillumination, careful peripheral examinations, modern vitrectomy platforms, and appropriate training may lead to outcomes that are detrimental to patient safety.

Purpose: To analyze and provide an overview of the incidence, management, and prevention of conjunctival erosion in Argus II clinical trial subjects and postapproval patients. Methods: This retrospective analysis followed the results of 274 patients treated with the Argus II Retinal Prosthesis System between June 2007 and November 2017, including 30 subjects from the US and European clinical trials, and 244 patients in the postapproval phase. Results were gathered for incidence of a serious adverse event, incidence of conjunctival erosion, occurrence sites, rates of erosion, and erosion timing. Results: Overall, 60% of subjects in the clinical trial subjects versus 83% of patients in the postapproval phase did not experience device- or surgery-related serious adverse events. In the postapproval phase, conjunctival erosion had an incidence rate of 6.2% over 5 years and 11 months. In 55% of conjunctival erosion cases, erosion occurred in the inferotemporal quadrant, 25% in the superotemporal quadrant, and 20% in both. Sixty percent of the erosion events occurred in the first 15 months after implantation, and 85% within the first 2.5 years. Conclusion: Reducing occurrence of conjunctival erosion in patients with the Argus II Retinal Prosthesis requires identification and minimization of risk factors before and during implantation. Implementing inverted sutures at the implant tabs, use of graft material at these locations as well as Mersilene rather than nylon sutures, and accurate Tenon's and conjunctiva closure are recommended for consideration in all patients.