Epimacular brachytherapy for previously treated neovascular age-related macular degeneration: month 36 results of the MERLOT randomised controlled trial.

BACKGROUND/AIM: To assess the long-term safety and efficacy of epimacular brachytherapy (EMB) for chronic, active, neovascular age-related macular degeneration (nAMD). METHODS: This pivotal, randomised, controlled surgical device trial recruited patients with chronic nAMD receiving intravitreal ranibizumab from 24 UK hospitals. Participants were randomised to either pars plana vitrectomy with 24 Gray EMB and pro re nata (PRN) ranibizumab (n=224) or PRN ranibizumab monotherapy (n=119). Although masking was not possible, masked clinicians assessed best-corrected visual acuity (BCVA) and imaging. After month 24, participants reverted to standard care, with either ranibizumab or aflibercept, returning for a month 36 study visit. RESULTS: Of 363 participants, 309 (85.1%) completed month 36. The number of injections was 12.1±8.1 in the EMB group versus 11.4±6.1 in the ranibizumab group (difference 0.7, 95% CI of difference -0.9 to 2.3, p=0.41) between months 1 and 36, and 3.6±3.3 (n=200) versus 3.9±2.7 (n=102) (difference -0.3, 95% CI of difference -1.0 to 0.4, p=0.43) between months 25 and 36 (standard care). Over 36 months, BCVA change was -19.7±18.5 letters in the EMB group and -4.8±12.5 in the ranibizumab group (difference -14.9, 95% CI of difference -18.5 to -11.2, p<0.0001). The month 36 BCVA of 20 EMB-treated participants with microvascular abnormalities (MVAs) at month 24 was similar to EMB-treated participants without MVAs (-21.8 vs -19.4 letters, p=0.65). CONCLUSION: EMB does not reduce the number of anti-vascular endothelial growth factor (VEGF) injections, either within or outside of a trial setting, and is associated with worse BCVA than anti-VEGF monotherapy. TRIAL REGISTRATION NUMBER: NCT01006538.

Evaluation of Month-24 Efficacy and Safety of Epimacular Brachytherapy for Previously Treated Neovascular Age-Related Macular Degeneration: The MERLOT Randomized Clinical Trial.

Importance: Although anti-vascular endothelial growth factor (VEGF) treatment offers better outcomes than the natural history of neovascular age-related macular degeneration (ARMD), a less burdensome, less expensive, and more durable treatment is needed. Objective: To assess the efficacy and safety of epimacular brachytherapy (EMB) for chronic, active, neovascular ARMD. Design, Setting, and Participants: The Macular Epiretinal Brachytherapy vs Ranibizumab (Lucentis) Only Treatment (MERLOT) pivotal device trial was conducted at 24 National Health Service hospitals across the UK. Patients who had neovascular ARMD and received intravitreal ranibizumab were enrolled between November 10, 2009, and January 30, 2012. Eligible patients were randomized 2:1 and were stratified by lens status and angiographic lesion type to receive either EMB plus as-needed ranibizumab or as-needed ranibizumab monotherapy. Participants were followed up monthly for 24 months and then assessed at a final visit at month 36. Masking of participants and clinicians was not possible, but best-corrected visual acuity (BCVA) and imaging were analyzed by masked assessors. Analysis followed the intent-to-treat approach. Interventions: Pars plana vitrectomy with 24 Gy EMB plus as-needed ranibizumab vs as-needed ranibizumab monotherapy. Main Outcomes and Measures: Coprimary outcomes were the number of as-needed ranibizumab injections and the mean change in Early Treatment Diabetic Retinopathy Study (ETDRS) BCVA with a noninferiority margin of -5 ETDRS letters. Secondary outcomes were the percentage of participants losing fewer than 15 ETDRS letters and gaining 0 or more or 15 or more ETDRS letters and the mean change in angiographic total lesion size, choroidal neovascularization size, and foveal thickness on optical coherence tomography. Results: Of 363 participants, 329 (90.6%) completed 24 months of follow-up (222 participants in the EMB group and 107 in the ranibizumab group). The mean (SD) age of the combined groups was 76.5 (7.4) years. The mean (SD) number of ranibizumab injections was 9.3 (6.7) in the EMB group and 8.3 (4.5) in the ranibizumab group, with a difference of 1.0 injection (95% CI, -0.3 to 2.3; P = .13). The mean (SD) BCVA change was -11.2 (15.7) ETDRS letters in the EMB group and -1.4 (10.9) ETDRS letters in the ranibizumab group, with a difference of 9.8 ETDRS letters (95% CI, -6.7 to -12.9). In the EMB group, 65.6% of participants (160 of 244) lost fewer than 15 ETDRS letters vs 86.6% (103 of 119) in the ranibizumab group, with a difference of 21% (95% CI, 12.4%-29.5%; P < .001). Microvascular abnormalities occurred in 20 of 207 eyes (9.7%) in the EMB group and 1 of 97 eyes (1.0%) in the ranibizumab group. These abnormalities occurred outside the foveal center, and there were no unexpected safety concerns. Conclusions and Relevance: The MERLOT trial found that despite the acceptable safety of EMB, it did not reduce the number of ranibizumab injections and was associated with worse visual acuity than anti-VEGF treatment alone; these results do not support EMB use as an adjunct treatment for chronic, active neovascular ARMD. Trial Registration: ClinicalTrials.gov Identifier: NCT01006538.

Central retinal artery occlusion during vitrectomy: Immediate retinal revascularization following induction of posterior vitreous detachment.

PURPOSE: To describe a patient with acute central retinal artery occlusion (CRAO) during vitrectomy surgery and the possible role of vitrectomy in acute CRAO management. OBSERVATIONS: An 84-year-old man presented with broad vitreomacular traction and epiretinal membrane in the right eye. Preoperative assessment clearly showed normal retinal vasculature. On starting vitrectomy, complete CRAO with marked segmentation of all retinal vessels was noted. Vitrectomy was performed in the usual manner and once the posterior hyaloid detached from the disc, immediate complete revascularization of the retinal vessels was noted. The patient had a complete visual recovery. CONCLUSIONS AND IMPORTANCE: Immediate vitrectomy with induction of posterior vitreous detachment may have a role in selected cases of acute CRAO, particularly if performed within a short window.

Epimacular Brachytherapy for Previously Treated Neovascular Age-Related Macular Degeneration (MERLOT): A Phase 3 Randomized Controlled Trial.

PURPOSE: To assess the safety and efficacy of epimacular brachytherapy (EMB) for patients with chronic, active, neovascular age-related macular degeneration (AMD). DESIGN: Phase 3 randomized controlled trial. PARTICIPANTS: Patients (n = 363) with neovascular AMD already receiving intravitreal ranibizumab injections. INTERVENTION: Either pars plana vitrectomy with 24-gray EMB and ongoing pro re nata (PRN) ranibizumab (n = 224) or ongoing PRN ranibizumab monotherapy (n = 119). MAIN OUTCOME MEASURES: The coprimary outcomes, at 12 months, were the number of PRN ranibizumab injections and Early Treatment of Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (VA). Secondary outcomes included the proportion of participants losing fewer than 15 ETDRS letters, angiographic total lesion size, choroidal neovascularization (CNV) size, and optical coherence tomography (OCT) foveal thickness. A predefined subgroup analysis tested the influence of baseline ocular characteristics on the response to EMB. RESULTS: The mean number of PRN ranibizumab injections was 4.8 in the EMB arm and 4.1 in the ranibizumab monotherapy arm (P = 0.068). The mean VA change was -4.8 letters in the EMB arm and -0.9 letters in the ranibizumab arm (95% confidence interval of difference between groups, -6.6 to -1.8 letters). The proportion of participants losing fewer than 15 letters was 84% in the EMB arm and 92% in the ranibizumab arm (P = 0.007). In the EMB arm, the mean total lesion size increased by 1.2 mm(2) versus 0.4 mm(2) in the ranibizumab arm (P = 0.27). The CNV size decreased by 0.5 mm(2) in the EMB arm and by 1.3 mm(2) in the ranibizumab arm (P = 0.27). The OCT foveal thickness decreased by 1.0 µm in the EMB arm and by 15.7 µm in the ranibizumab arm (P = 0.43). Most subgroups favored ranibizumab monotherapy, some significantly so. One participant showed retinal vascular abnormality attributed to radiation, but otherwise safety was acceptable. CONCLUSIONS: These results do not support the use of EMB for chronic, active, neovascular AMD. Safety is acceptable out to 12 months, but radiation retinopathy can occur later, so further follow-up is planned.

Scleral hydraulic conductivity and macromolecular diffusion in patients with uveal effusion syndrome.

PURPOSE: To determine whether uveal effusion syndrome (UES) is caused by altered scleral permeability to water and large molecules. METHODS: Transscleral water movement was measured using surgically removed sclera clamped in a modified Ussing chamber and connected to a water column set at intraocular pressure. Sclera was also clamped between two hemichambers, and transscleral diffusion of FITC-dextrans (4.4-77 kDa) was measured with a spectrophotometer. Clinical data were prospectively collected using postal questionnaires. RESULTS: Ten patients (mean age, 63 years; mean spherical equivalent, +4.7 D) had a median preoperative visual acuity of 0.20 that improved to 0.33 after surgery. Nine eyes showed visual improvement, three worsened, and two were unchanged. Histology showed disorganization of collagen fibrils, with amorphous deposits expanding the interfibrillary spaces. The mean thickness (+/-1 SD) of the excised scleral specimens was 585 +/- 309 microm, and the mean specific hydraulic conductivity was 23.9 +/- 27.5 x 10(-14) cm(2), compared with 5.8 +/- 3.9 x 10(-14) cm(2) in age-matched control specimens (P = 0.068). Three specimens had hydraulic conductivity above the 95% CI of the controls. Control eyes showed a significant reduction in diffusion coefficient (D) with age. Eyes had a mean D of 5.69 +/- 5.35 x 10(-8) cm(2) x s(-1), similar to control eyes (6.14 +/- 2.40 x 10(-8) cm(2) x s(-1), 20 kDa dextran). In one eye, the result was higher than the 95% CI of the control; in three, it was lower. CONCLUSIONS: UES is not caused by reduced scleral hydraulic conductivity, which tends to be higher than expected. Reduced macromolecular diffusion may impede the normal transscleral egress of albumin with subsequent osmotic fluid retention in some, but not all eyes.