Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus.

BACKGROUND: Keratoconus is the most common corneal dystrophy. It can cause loss of uncorrected and best-corrected visual acuity through ectasia (thinning) of the central or paracentral cornea, irregular corneal scarring, or corneal perforation. Disease onset usually occurs in the second to fourth decade of life, periods of peak educational attainment or career development. The condition is lifelong and sight-threatening. Corneal collagen crosslinking (CXL) using ultraviolet A (UVA) light applied to the cornea is the only treatment that has been shown to slow progression of disease. The original, more widely known technique involves application of UVA light to de-epithelialized cornea, to which a photosensitizer (riboflavin) is added topically throughout the irradiation process. Transepithelial CXL is a recently advocated alternative to the standard CXL procedure, in that the epithelium is kept intact during CXL. Retention of the epithelium offers the putative advantages of faster healing, less patient discomfort, faster visual rehabilitation, and less risk of corneal haze. OBJECTIVES: To assess the short- and long-term effectiveness and safety of transepithelial CXL compared with epithelium-off CXL for progressive keratoconus. SEARCH METHODS: To identify potentially eligible studies, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2020, Issue 1); Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Health Sciences Literature database (LILACS); ClinicalTrials.gov; and World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not impose any date or language restrictions. We last searched the electronic databases on 15 January 2020. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in which transepithelial CXL had been compared with epithelium-off CXL in participants with progressive keratoconus. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. MAIN RESULTS: We included 13 studies with 723 eyes of 578 participants enrolled; 13 to 119 participants were enrolled per study. Seven studies were conducted in Europe, three in the Middle East, and one each in India, Russia, and Turkey. Seven studies were parallel-group RCTs, one study was an RCT with a paired-eyes design, and five studies were RCTs in which both eyes of some or all participants were assigned to the same intervention. Eleven studies compared transepithelial CXL with epithelium-off CXL in participants with progressive keratoconus. There was no evidence of an important difference between intervention groups in maximum keratometry (denoted 'maximum K' or 'Kmax'; also known as steepest keratometry measurement) at 12 months or later (mean difference (MD) 0.99 diopters (D), 95% CI -0.11 to 2.09; 5 studies; 177 eyes; I2 = 41%; very low certainty evidence). Few studies described other outcomes of interest. The evidence is very uncertain that epithelium-off CXL may have a small (data from two studies were not pooled due to considerable heterogeneity (I2 = 92%)) or no effect on stabilization of progressive keratoconus compared with transepithelial CXL; comparison of the estimated proportions of eyes with decreases or increases of 2 or more diopters in maximum K at 12 months from one study with 61 eyes was RR 0.32 (95% CI 0.09 to 1.12) and RR (non-event) 0.86 (95% CI 0.74 to 1.00), respectively (very low certainty). We did not estimate an overall effect on corrected-distance visual acuity (CDVA) because substantial heterogeneity was detected (I2 = 70%). No study evaluated CDVA gain or loss of 10 or more letters on a logarithm of the minimum angle of resolution (logMAR) chart. Transepithelial CXL may result in little to no difference in CDVA at 12 months or beyond. Four studies reported that either no adverse events or no serious adverse events had been observed. Another study noted no change in endothelial cell count after either procedure. Moderate certainty evidence from 4 studies (221 eyes) found that epithelium-off CXL resulted in a slight increase in corneal haze or scarring when compared to transepithelial CXL (RR (non-event) 1.07, 95% CI 1.01 to 1.14). Three studies, one of which had three arms, compared outcomes among participants assigned to transepithelial CXL using iontophoresis versus those assigned to epithelium-off CXL. No conclusive evidence was found for either keratometry or visual acuity outcomes at 12 months or later after surgery. Low certainty evidence suggests that transepithelial CXL using iontophoresis results in no difference in logMAR CDVA (MD 0.00 letter, 95% CI -0.04 to 0.04; 2 studies; 51 eyes). Only one study examined gain or loss of 10 or more logMAR letters. In terms of adverse events, one case of subepithelial infiltrate was reported after transepithelial CXL with iontophoresis, whereas two cases of faint corneal scars and four cases of permanent haze were observed after epithelium-off CXL. Vogt's striae were found in one eye after each intervention. The certainty of the evidence was low or very low for the outcomes in this comparison due to imprecision of estimates for all outcomes and risk of bias in the studies from which data have been reported. AUTHORS' CONCLUSIONS: Because of lack of precision, frequent indeterminate risk of bias due to inadequate reporting, and inconsistency in outcomes measured and reported among studies in this systematic review, it remains unknown whether transepithelial CXL, or any other approach, may confer an advantage over epithelium-off CXL for patients with progressive keratoconus with respect to further progression of keratoconus, visual acuity outcomes, and patient-reported outcomes (PROs). Arrest of the progression of keratoconus should be the primary outcome of interest in future trials of CXL, particularly when comparing the effectiveness of different approaches to CXL. Furthermore, methods of assessing and defining progressive keratoconus should be standardized. Trials with longer follow-up are required in order to assure that outcomes are measured after corneal wound-healing and stabilization of keratoconus. In addition, perioperative, intraoperative, and postoperative care should be standardized to permit meaningful comparisons of CXL methods. Methods to increase penetration of riboflavin through intact epithelium as well as delivery of increased dose of UVA may be needed to improve outcomes. PROs should be measured and reported. The visual significance of adverse outcomes, such as corneal haze, should be assessed and correlated with other outcomes, including PROs.

Treatment regimens for administration of anti-vascular endothelial growth factor agents for neovascular age-related macular degeneration.

BACKGROUND: Age-related macular degeneration (AMD) is one of the leading causes of permanent blindness worldwide. The current mainstay of treatment for neovascular AMD (nAMD) is intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents: aflibercept, ranibizumab, and off-label bevacizumab. Injections can be given monthly, every two or three months ('extended-fixed'), or as needed (pro re nata (PRN)). A variant of PRN is 'treat-and-extend' whereby injections are resumed if recurrence is detected and then delivered with increasing intervals. Currently, injection frequency varies among practitioners, which underscores the need to characterize an optimized approach to nAMD management. OBJECTIVES: To investigate the effects of monthly versus non-monthly intravitreous injection of an anti-VEGF agent in people with newly diagnosed nAMD. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS, and three trials registers from 2004 to October 2019; checked references; handsearched conference abstracts; and contacted pharmaceutical companies to identify additional studies. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared different treatment regimens for anti-VEGF agents in people with newly diagnosed nAMD. We considered standard doses only (ranibizumab 0.5 mg, bevacizumab 1.25 mg, aflibercept 2.0 mg, or a combination of these). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods for trial selection, data extraction, and analysis. MAIN RESULTS: We included 15 RCTs. The total number of participants was 7732, ranging from 37 to 2457 in each trial. The trials were conducted worldwide. Of these, six trials exclusively took place in the US, and three included centers from more than one country. Eight trials were at high risk of bias for at least one domain and all trials had at least one domain at unclear risk of bias. Seven trials (3525 participants) compared a PRN regimen with a monthly injection regimen, of which five trials delivered four to eight injections using standard PRN and three delivered nine or 10 injections using a treat-and-extend regimen in the first year. The overall mean change in best-corrected visual acuity (BCVA) at one year was +8.8 letters in the monthly injection group. Compared to the monthly injection, there was moderate-certainty evidence that the mean difference (MD) in BCVA change at one year for the standard PRN subgroup was -1.7 letters (95% confidence interval (CI) -2.8 to -0.6; 4 trials, 2299 participants), favoring monthly injections. There was low-certainty evidence of a similar BCVA change with the treat-and-extend subgroup (0.5 letters, 95% CI -3.1 to 4.2; 3 trials, 1226 participants). Compared to monthly injection, there was low-certainty evidence that fewer participants gained 15 or more lines of vision with standard PRN treatment at one year (risk ratio (RR) 0.87, 95% CI 0.76 to 0.99; 4 trials, 2299 participants) and low-certainty evidence of a similar gain with treat-and-extend versus monthly regimens (RR 1.11, 95% CI 0.91 to 1.36; 3 trials, 1169 participants). The mean change in central retinal thickness was a decrease of -166 µm in the monthly injection group; the MD compared with standard PRN was 21 µm (95% CI 6 to 32; 4 trials, 2215 participants; moderate-certainty evidence) and with treat-and extend was 22 µm (95% CI 37 to -81 µm; 2 trials, 635 participants; low-certainty evidence), in favor of monthly injection. Only one trial (498 participants) measured quality of life and reported no evidence of a difference between regimens, but data could not be extracted (low-certainty evidence). Both PRN regimens (standard and 'treat-and-extend') used fewer injections than monthly regimens (standard PRN: MD -4.6 injections, 95% CI -5.4 to -3.8; 4 trials, 2336 participants; treat-and-extend: -2.4 injections, 95% CI -2.7 to -2.1 injections; moderate-certainty evidence for both comparisons). Two trials provided cost data (1105 participants, trials conducted in the US and the UK). They found that cost differences between regimens were reduced if bevacizumab rather than aflibercept or ranibizumab were used, since bevacizumab was less costly (low-certainty evidence). PRN regimens were associated with a reduced risk of endophthalmitis compared with monthly injections (Peto odds ratio (OR) 0.13, 95% CI 0.04 to 0.46; 6 RCTs, 3175 participants; moderate-certainty evidence). Using data from all trials included in this review, we estimated the risk of endophthalmitis with monthly injections to be 8 in every 1000 people per year. The corresponding risk for people receiving PRN regimens was 1 in every 1000 people per year (95% CI 0 to 4). Three trials (1439 participants) compared an extended-fixed regimen (number of injections reported in only one large trial: 7.5 in one year) with monthly injections. There was moderate-certainty evidence that BCVA at one year was similar for extended-fixed and monthly injections (MD in BCVA change compared to extended-fixed group: -1.3 letters, 95% CI -3.9 to 1.3; RR of gaining 15 letters or more: 0.94, 95% CI 0.80 to 1.10). The change in central retinal thickness was a decrease of 137 µm in the monthly group; the MD with the extended-fixed group was 8 µm (95% CI -11 to 27; low-certainty evidence). The frequency of endophthalmitis was lower in the extended-fixed regimen compared to the monthly group, but this estimate was imprecise (RR 0.19, 95% CI 0.03 to 1.11; low-certainty evidence). If we assumed a risk of 8 cases of endophthalmitis in 1000 people receiving monthly injections over one year, then the corresponding risk with extended-fixed regimen was 2 in 1000 people (95% CI 0 to 9). Other evidence comparing different extended-fixed or PRN regimens yielded inconclusive results. AUTHORS' CONCLUSIONS: We found that, at one year, monthly regimens are probably more effective than PRN regimens using seven or eight injections in the first year, but the difference is small and clinically insignificant. Endophthalmitis is probably more common with monthly injections and differences in costs between regimens are higher if aflibercept or ranibizumab are used compared to bevacizumab. This evidence only applies to settings in which regimens are implemented as described in the trials, whereas undertreatment is likely to be common in real-world settings. There are no data from RCTs on long-term effects of different treatment regimens.

Anti-vascular endothelial growth factor for neovascular glaucoma.

BACKGROUND: Neovascular glaucoma (NVG) is a potentially blinding, secondary glaucoma. It is caused by the formation of abnormal new blood vessels, which prevent normal drainage of aqueous from the anterior segment of the eye. Anti-vascular endothelial growth factor (anti-VEGF) medications are specific inhibitors of the primary mediators of neovascularization. Studies have reported the effectiveness of anti-VEGF medications for the control of intraocular pressure (IOP) in NVG. OBJECTIVES: To assess the effectiveness of intraocular anti-VEGF medications, alone or with one or more type of conventional therapy, compared with no anti-VEGF medications for the treatment of NVG. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register); MEDLINE; Embase; PubMed; and LILACS to 22 March 2019; metaRegister of Controlled Trials to 13 August 2013; and two additional trial registers to 22 March 2019. We did not use any date or language restrictions in the electronic search for trials. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of people treated with anti-VEGF medications for NVG. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the search results for trials, extracted data, and assessed risk of bias, and the certainty of the evidence. We resolved discrepancies through discussion. MAIN RESULTS: We included four RCTs (263 participants) and identified one ongoing RCT. Each trial was conducted in a different country: China, Brazil, Egypt, and Japan. We assessed the trials to have an unclear risk of bias for most domains due to insufficient information. Two trials compared intravitreal bevacizumab combined with Ahmed valve implantation and panretinal photocoagulation (PRP) with Ahmed valve implantation and PRP. We did not combine these two trials due to substantial clinical and statistical heterogeneity. One trial randomised participants to receive an injection of either an intravitreal anti-VEGF medication or placebo at the first visit, followed by non-randomised treatment according to clinical findings after one week. The last trial randomised participants to PRP with and without ranibizumab, but details of the study were unavailable for further analysis. Two trials that examined IOP showed inconsistent results. One found inconclusive results for mean IOP between participants who received anti-VEGF medications and those who did not, at one month (mean difference [MD] -1.60 mmHg, 95% confidence interval [CI] -4.98 to 1.78; 40 participants), and at one year (MD 1.40 mmHg, 95% CI -4.04 to 6.84; 30 participants). Sixty-five percent of the participants with anti-VEGF medications achieved IOP ≤ 21 mmHg, versus 60% without anti-VEGF medications. In another trial, those who received anti-VEGF medications were more likely to reduce their IOP than those who did not receive them, at one month (MD -6.50 mmHg, 95% CI -7.93 to -5.07; 40 participants), and at one year (MD -12.00 mmHg, 95% CI -16.79 to -7.21; 40 participants). Ninety-five percent of the participants with anti-VEGF medications achieved IOP ≤ 21 mmHg, versus 50% without anti-VEGF medications. The certainty of a body of evidence was low for this outcome due to limitations in the design and inconsistency of results between studies. Post-operative complications included anterior chamber bleeding (3 eyes) and conjunctival hemorrhage (2 participants) in the anti-VEGF medications group, and retinal detachment and phthisis bulbi (1 participant each) in the control group. The certainty of evidence is low due to imprecision of results and indirectness of evidence. No trial reported the proportion of participants with improvement in visual acuity, proportion of participants with complete regression of new iris vessels, or the proportion of participants with relief of pain and resolution of redness at four- to six-week, or one-year follow-up. AUTHORS' CONCLUSIONS: Currently available evidence is uncertain regarding the long-term effectiveness of anti-VEGF medications, such as intravitreal ranibizumab or bevacizumab or aflibercept, as an adjunct to conventional treatment in lowering IOP in NVG. More research is needed to investigate the long-term effect of these medications compared with, or in addition to, conventional surgical or medical treatment in lowering IOP in NVG.

Evaluation of Clinical Questions and Patient-Important Outcomes Associated With the Treatment of Age-Related Macular Degeneration.

Importance: Identifying and prioritizing unanswered clinical questions may help to best allocate limited resources for research associated with the treatment of age-related macular degeneration (AMD). Objective: To identify and prioritize clinical questions and outcomes for research associated with the treatment of AMD through engagement with professional and patient stakeholders. Design, Setting, and Participants: Multiple cross-sectional survey questions were used in a modified Delphi process for panel members of US and international organizations, the American Academy of Ophthalmology (AAO) Retina/Vitreous Panel (n=7), health care professionals from the American Society of Retinal Specialists (ASRS) (n=90), Atlantic Coast Retina Conference (ACRC) and Macula 2017 meeting (n=34); and patients from MD (Macular Degeneration) Support (n=46). Data were collected from January 20, 2015, to January 9, 2017. Main Outcomes and Measures: The prioritizing of clinical questions and patient-important outcomes for AMD. Results: Seventy clinical questions were derived from the AAO Preferred Practice Patterns for AMD and suggestions by the AAO Retina/Vitreous Panel. The AAO Retina/Vitreous Panel assessed all 70 clinical questions and rated 17 of 70 questions (24%) as highly important. Health care professionals assessed the 17 highly important clinical questions and rated 12 of 17 questions (71%) as high priority for research to answer; 9 of 12 high-priority clinical questions were associated with aspects of anti-vascular endothelial growth factor agents. Patients assessed the 17 highly important clinical questions and rated all as high priority. Additionally, patients identified 6 of 33 outcomes (18%) as most important to them (choroidal neovascularization, development of advanced AMD, retinal hemorrhage, gain of vision, slowing vision loss, and serious ocular events). Conclusions and Relevance: Input from 4 stakeholder groups suggests good agreement on which 12 priority clinical questions can be used to underpin research related to the treatment of AMD. The 6 most important outcomes identified by patients were balanced between intended effects of AMD treatment (eg, slowing vision loss) and adverse events. Consideration of these patient-important outcomes may help to guide clinical care and future areas of research.

Intravitreal Bevacizumab Versus Ranibizumab for Treatment of Neovascular Age-Related Macular Degeneration: Findings from a Cochrane Systematic Review.

TOPIC: To summarize the relative effects of bevacizumab (Avastin; Genentech, Inc, South San Francisco, CA) and ranibizumab (Lucentis; Genentech, Inc.), using findings from a Cochrane Eyes and Vision Group systematic review. CLINICAL RELEVANCE: Neovascular age-related macular degeneration (NVAMD) is the most common cause of uncorrectable vision loss among the elderly in developed countries. Bevacizumab and ranibizumab are the most frequently used anti-vascular endothelial growth factor (VEGF) agents injected intravitreally to treat NVAMD. METHODS: For this systematic review, we included only randomized controlled trials in which the 2 anti-VEGF agents had been compared directly. The primary outcome was 1-year gain in best-corrected visual acuity (BCVA) of ≥15 letters. We followed Cochrane methods for trial selection, data extraction, and data analyses. Relative effects of bevacizumab versus ranibizumab are presented as estimated risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs). RESULTS: We identified 6 eligible randomized controlled trials with 2809 participants. The proportion of eyes that gained ≥15 letters of BCVA by 1 year was similar for the 2 agents when the same regimens were compared (RR, 0.90; 95% CI, 0.73-1.11). The mean change in BCVA from baseline also was similar (MD, -0.5 letter; 95% CI, -1.6 to +0.6). Other BCVA and quality of life outcomes were similar for the 2 agents. One-year treatment cost with ranibizumab was 5.1 and 25.5 times the cost for bevacizumab in the 2 largest trials. Ocular adverse events were uncommon (<1%), and rates were similar for the 2 agents. CONCLUSIONS: We found no important difference in effectiveness or safety between bevacizumab and ranibizumab for NVAMD treatment, but there was a large cost difference.