On the relationship between visual acuity and central retinal (macular) thickness after interventions for macular oedema in diabetics: a review

Relationship Between Macular Thickness and Visual Acuity in the Treatment of Diabetic Macular Edema With Anti-VEGF Therapy: Systematic Review

Purpose:

To examine the relationship between central macular thickness (CMT) measured by optical coherence tomography (OCT) and visual acuity (VA) in patients with center-involving diabetic macular edema (DME) receiving antivascular endothelial growth factor (anti-VEGF) treatment.

Methods:

Peer-reviewed articles from 2016 to 2020 reporting intravitreal injections of bevacizumab, ranibizumab, or aflibercept that provided data on pretreatment (baseline) and final retinal thickness (CMT) and visual acuity (VA) were identified. The relationship between relative changes was assessed via a linear random-effects regression model controlling for treatment group.

Results:

No significant association between the logarithm of the minimum angle of resolution (logMAR) VA and CMT was found in 41 eligible studies evaluating 2667 eyes. The observed effect estimate was a 0.12 increase (95% CI, −0.124 to 2.47) in logMAR VA per 100 µm reduction in CMT after treatment change. There were no significant differences in logMAR VA between the anti-VEGF treatment groups.

Conclusions:

There was no statistically significant relationship between the change in logMAR VA and change in CMT as well as no significant effect of the type of anti-VEGF treatment on the change in logMAR VA. Although OCT analysis, including measurements of CMT, will continue to be an integral part of the management of DME, further exploration is needed on additional anatomic factors that might contribute to visual outcomes.

Reduction in Retinal Thickness Fluctuations After Treatment With Fluocinolone Acetonide Implant for DME: A Post-Hoc Analysis of the USER Study

BACKGROUND AND OBJECTIVE

Assess fluocinolone acetonide implant (FAc) effects on diabetic macular edema (DME) retinal thickness fluctuations.

PATIENTS AND METHODS

A post-hoc chart review of the real-world USER study analyzed patients receiving 0.2 μg/day FAc implant. The percentage of eyes with central subfield thickness (CST) of 300 µm or less were compared pre- and post-FAc implant; mean retinal thickness amplitude (RTA), retinal thickness standard deviation (RTSD), and two case studies were analyzed.

RESULTS

One hundred thirty patients (mean age: 69.6 years) presented; CST was available for 120 of 160 treated eyes. Mean RTA decreased significantly post-FAc implant (P < .001) regardless of baseline visual acuity (VA). Correlations with last-observed VA (R²) were: RTA, 0.1197; retinal thickness standard deviation (RTSD), 0.1526; and area under the CST-time curve (AUC CST), 0.0981. After FAc implant, the percentage of eyes with CST of 300 μm or less was significantly greater versus baseline (P < .05).

CONCLUSIONS

Retinal thickness fluctuations significantly declined after FAc and correlated with improvement in VA. Both RTSD and RTA measures correlated more closely to last observed VA than AUC CST itself. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:298-306.].

Association Between Vessel Density and Visual Acuity in Patients With Diabetic Retinopathy and Poorly Controlled Type 1 Diabetes

Importance

Capillary dropout is a hallmark of diabetic retinopathy, but its role in visual loss remains unclear.

Objective

To examine how macular vessel density is correlated with visual acuity (VA) in patients younger than 40 years who have type 1 diabetes without macular edema but who have diabetic retinopathy requiring panretinal photocoagulation.

Design, Settings, and Participants

Retrospective cohort study of VA and optical coherence tomography angiography data collected from consecutive patients during a single visit to Lariboisière Hospital, a tertiary referral center in Paris, France. The cohort included 22 eyes of 22 patients with type 1 diabetes without macular edema but with bilateral rapidly progressive diabetic retinopathy that was treated with panretinal photocoagulation between August 15, 2015, and December 30, 2016. Eyes were classified into 2 groups by VA: normal (logMAR, 0; Snellen equivalent, 20/20) and decreased (logMAR, >0; Snellen equivalent, <20/20). The control group included 12 eyes from age-matched healthy participants with normal vision.

Main Outcomes and Measures

Visual acuity and mean vessel density in 4 retinal vascular plexuses: the superficial vascular plexus and the deep capillary complex, which comprises the intermediate capillary plexus and the deep capillary plexus.

Results

Of the 22 participants, 11 (50%) were men, mean (SD) age was 30 (6) years, and mean (SD) hemoglobin A1c level was 8.9% (1.6%). Of the 22 eyes with diabetic retinopathy, 13 (59%) had normal VA and 9 (41%) had decreased VA (mean [SD]: logMAR, 0.12 [0.04]; Snellen equivalent, 20/25). Mean [SE] vessel density was lower for eyes with diabetic retinopathy and normal VA compared with the control group in the superficial vascular plexus (44.1% [0.9%] vs 49.1% [0.9%]; difference, -5.0% [1.3%]; 95% CI, -7.5% to -2.4%; P < .001), in the deep capillary complex (44.3% [1.2%] vs 50.6% [1.3%]; difference, -6.3% [1.8%]; 95% CI, -9.9% to -2.7%; P = .001), in the intermediate capillary plexus (43.8% [1.2%] vs 49.3% [1.2%]; difference, -5.5% [1.7%]; 95% CI, -9.0% to -2.0%; P = .003), and in the deep capillary plexus (24.5% [1.0%] vs 30.5% [1.0%]; difference, -6.1% [1.4%]; 95% CI, -8.9% to -3.2%; P < .001). Mean vessel density was lower in eyes with diabetic retinopathy and decreased VA compared with eyes with diabetic retinopathy and normal VA; the mean (SE) loss was more pronounced in the deep capillary complex (34.6% [1.5%] vs 44.3% [1.2%]; difference, -9.6% [1.9%]; 95% CI, -13.6% to -5.7%; P < .001), especially in the deep capillary plexus (15.2% [1.2%] vs 24.5% [1.0%]; difference, -9.3% [1.5%]; 95% CI, -12.4% to -6.1%; P < .001), than in the superficial vascular plexus (39.6% [1.1%] vs 44.1% [0.9%]; difference, -4.5% [1.4%]; 95% CI, -7.3% to -1.7%; P = .002).

Conclusions and Relevance

These data suggest that in patients with type 1 diabetes without macular edema but with severe nonproliferative or proliferative diabetic retinopathy, decreased VA may be associated with the degree of capillary loss in the deep capillary complex.

Ozurdex for refractory macular edema secondary to diabetes, vein occlusion, uveitis and pseudophakia

OBJECTIVE

To analyze the functional and morphological effects of the intravitreal dexamethasone implant (Ozurdex, Allergan) on patients with macular edema secondary to retinal vein occlusion (RVO), diabetic retinopathy (DME), posterior noninfectious uveitis (NIU), or pseudophakic Irvine-Gass syndrome (IGS).

METHODS

144 charts were retrospectively reviewed; 100 eyes met inclusion criteria for analysis: at least one intravitreal dexamethasone implant injection, refractory to antivascular endothelial growth factor, and had ≥6 months of follow-up postinsertion. The primary outcome was the efficacy of the dexamethasone implant in reducing macular edema as measured by reduction in central retinal thickness (CRT). Secondary outcomes included visual acuity (VA), duration of treatment efficacy (measured by time to next treatment), and safety. The Wilcoxon signed-rank test was used to compare values from baseline, and Kaplan-Meier survival curves were used to analyze time to retreatment.

RESULTS

There were 28 patients with RVO, 30 with DME, 24 with posterior NIU, and 18 with IGS. VA improved from baseline to month 6 in all groups, but was not statistically significant. CRT improved in all 4 groups, and was statistically significant for DME (p = 0.008) and NIU (p = 0.05). At 3 months, 34 patients (41.5%) required retreatment; by month 6, 46 patients (56.1%) required retreatment. There was a large variation between the groups in number of patients requiring intraocular pressure (IOP)-lowering medications. Two patients needed IOP-lowering surgery. One patient developed endophthalmitis.

CONCLUSION

The use of intravitreal dexamethasone implants in patients with refractory retinal diseases is well tolerated and results in consistently improved anatomic outcomes, but the positive anatomic outcomes are not necessarily correlated to improvements in visual function. Patients who are treated earlier in the disease process will had better outcomes. This patient population were refractory to treatment and, therefore, have less-predictable functional outcomes.

Real-Life Clinical Effectiveness of Razumab® (the World's First Biosimilar of Ranibizumab) in Retinal Vein Occlusion: A Subgroup Analysis of the Pooled Retrospective RE-ENACT Study

BACKGROUND

This subgroup analysis of the RE-ENACT study evaluates the effectiveness of Razumab® (the world's first biosimilar of ranibizumab by Intas Pharmaceuticals Ltd.) in Indian patients with retinal vein occlusion (RVO).

METHODS

The data on patients with RVO who had received ≥3 injections of Razumab® between January and August 2016 were analyzed. Endpoints were: improvement in best corrected visual acuity (BCVA), and a decrease in central macular thickness (CMT), intraretinal fluid (IRF), and subretinal fluid (SRF) from baseline at weeks 4, 8, and 12.

RESULTS

Of 160 patients, the majority (61.87%) were men. The mean (±SE) BCVA improved from baseline (0.76 ± 0.04) to week 4 (0.73 ± 0.03; p = 0.0656), which attained significance at week 8 (0.55 ± 0.02; p < 0.0001) and week 12 (0.47 ± 0.02; p < 0.0001). The mean (±SE) CMT significantly decreased from baseline (447.60 ± 10.91 μm) to week 4 (431.84 ± 10.92 μm; p = 0.0028), week 8 (339.28 ± 8.12 μm; p < 0.0001), and week 12 (298.23 ± 6.68 μm; p < 0.0001). The proportion of patients with IRF and SRF significantly (p < 0.0001) decreased from baseline to weeks 4, 8, and 12 (IRF: from 70.63 to 45.63, 39.38, and 30.00%, respectively; SRF: from 65.63 to 37.50, 28.13, and 24.38%, respectively). A subgroup analysis of branch RVO and central RVO showed similar results. No new safety concerns were observed.

CONCLUSION

Razumab® (biosimilar of ranibizumab) effectively improved visual acuity and disease outcomes in patients with RVO in a real-world setting with no new safety concerns.

CORRELATION BETWEEN CENTRAL FOVEAL THICKNESS AND VISUAL ACUITY IN PATIENTS WITH IDIOPATHIC VITREOMACULAR TRACTION

PURPOSE

To evaluate the impact of preoperative central foveal thickness (CFT) on visual acuity after surgery in patients with idiopathic vitreomacular traction and to calculate a cut-off value in preoperative CFT.

METHODS

Thirty-five patients with idiopathic vitreomacular traction were evaluated retrospectively. A complete ophthalmological examination including spectral domain optical coherence tomography was performed preoperatively and at 12 months after the surgery. Receiver operating characteristic analysis was used to determine the critical point for the CFT associated with improvement of 10 or more letters in visual acuity on the Early Treatment Diabetic Retinopathy Study.

RESULTS

Among 35 patients, the mean CFT at postoperative 12 months was significantly decreased from baseline (P = 0.001). Preoperative CFT and visual improvement were not significantly correlated (r = -0.090, P = 0.605), whereas preoperative CFT and preoperative visual acuity were significantly correlated (r = 0.757, P < 0.001). Improvement in CFT and visual improvement were also correlated significantly (r = 0.449, P = 0.007). According to the receiver operating characteristic analysis, the threshold CFT was 471 μm. When 15 patients with CFT thickness under 471 μm were evaluated, preoperative CFT was significantly correlated with improvement in visual acuity after the surgery (r = 0.561, P = 0.030).

CONCLUSION

Preoperative CFT is important for the visual prognosis of patients with vitreomacular traction. Preoperative CFT of these patients should be considered in surgical decisions.