Both Sides Now: A Look at Controversies Across Eye Care

Brooks Alldredge, OD, of the Pacific Cataract and Laser Institute, presented optometrists with arguments for and against numerous controversies in eye disease management at the 2021 Southeastern Education Congress of Optometry (SECO) meeting, held April 28 to May 2 in Atlanta. 

The “Controversies in Eye Care” course covered arguments both for and against potential controversial procedures, including immediate sequential bilateral cataract surgery, intravitreal anti-vascular endothelial growth factor (VEGF) treatment in patients with diabetic macular edema (DME) and good vision, and the potential obsolescence of retinal IV fluorescein angiography, among other topics. 

Immediate Sequential Bilateral Cataract Surgery. Per Dr Alldredge, the arguments in favor of immediate bilateral cataract surgery include patient convenience, less risk for patients with physical or cognitive impairments, and reduced overall costs. If patients were to undergo immediate bilateral cataract surgery, they would require only 1 trip to the operating room, fewer follow-up exams, less downtime and less time away from work, and increased access to surgery. However, the risk of bilateral endophthalmitis is a real concern, as is the risk of bilateral toxic anterior segment syndrome (0.22% incidence rate), and a drastic reduction in reimbursement for the operating physician. 

Data presented to rebut arguments against bilateral cataract surgery show that in developed countries, there were no reported cases of bilateral endophthalmitis as of April 2018. These data include a total of 95,606 patients in a 2011 retrospective study that highlighted the importance of steps needed to avoid cross contamination, like the use of 2 separate surgical trays. 

Bilateral toxic anterior segment syndrome is, reportedly, rarer now than it was a few years ago, due to practices that include vigorous cleaning of instruments, changes in cleaning detergents, and the adoption of disposable instruments with small lumen cannulas. 

In a retrospective study conducted in Northern California, 13,711 eyes underwent conventional surgery vs 3561 eyes that underwent immediate sequential bilateral cataract surgery. Results of the study show that there was no significant decrease in postoperative best corrected visual acuity or refractive error and no increased risk of complications. 

Intravitreal Anti-VEGF Treatment for Patients with DME with Good Vision. One argument in favor of this practice is that intravitreal anti-VEGF therapy is effective in treating vision loss associated with DME. Two studies — RISE and RIDE — demonstrated a 12.5 and 10.9 letter improvement in visual acuity with ranibizumab therapy. Results of the DRCR.net Protocol T Study showed the most significant improvement of 18.3 letters in patients treated with aflibercept. Finally, real-world data show that patients with DME and mild visual acuity loss had the worst response to anti-VEGF therapy. 

Arguments against this treatment protocol are illustrated by results of the DRCR.net Protocol V study, which included 720 eyes with center-involved DME and a visual acuity of 20/50 or better. Three groups of patients received either aflibercept every 4 weeks, prompt laser photocoagulation, or no treatment. At 2 years, the average visual acuity in each group was 20/20, and 16%, 17%, and 19% of patients in each group, respectively, lost 1 line of vision. 

Retinal IV Fluorescein Angiography Obsolescence. Currently, spectral domain optical coherence tomography (OCT) and OCT angiography (OCT-A) have replaced retinal IV fluorescein angiography to image retinal blood flow. OCT-A can successfully visualize the most common retinal vascular lesions that need treatment, including choroidal neovascularization, intraretinal microvascular abnormalities, and capillary nonperfusion. OCT-A also visualizes the retinal vascular layers — superficial, intermediate, and deep plexus— as well as providing enface and cross-sectional views. Perhaps most importantly, this method increases patient comfort and decreases the side effects, time, and technical skill needed for retinal IV fluorescein angiography. 

But as with all new technologies, the arguments against OCT-A are many: according to Dr Alldredge, OCT-A cannot be used to examine mid-peripheral and peripheral ischemia or NV, and indocyanine green angiography is still needed in order to visualize deeper lesions. To rebut this, though, the presentation suggests that OCT-A should be augmented with OCT, rather than with retinal IV fluorescein angiography and enhanced depth imaging. 

Other controversies include the use of nondilated, ultra-widefield retinal photography replacing dilated ophthalmoscopy, mandatory macular OCT before all cataract surgeries, and the current optional status of scleral depression in examining patients with symptomatic posterior vitreous detachment. 

Reference

Alldredge B. Controversies in eye disease management. Presented at: Southeastern Educational Congress of Optometry (SECO) 2021 Annual Meeting; April 28-May 2, 2021; Atlanta, GA. Course 505.