Aim

To show the characteristics and outcomes of patients with neovascular age-related macular degeneration (nAMD) who had extended remission (ER) while on a pro re nata (PRN) treatment protocol.

Methods

This was a retrospective case-control study of a consecutive series of patients with nAMD treated with a PRN antivascular endothelial growth factor (anti-VEGF) drug regimen. ER was defined as the absence of haemorrhage, intraretinal/subretinal fluid on optical coherence tomography and leakage on fluorescein angiography for 52 weeks after cessation of anti-VEGF therapy. Matching patients with nAMD who did not achieve ER were included as control group. Cox regression analysis was fitted to identify predictors of time to achieve ER and time to recurrence. A logistic regression analysis of baseline characteristics was used to identify predictors of achieving ER.

Results

Of 830 eyes treated with anti-VEGF monotherapy, 77 (9.2%) eyes achieved ER during a median follow-up of 236 weeks (range 70-525 weeks). Cox regression analysis showed that ER was achieved earlier in eyes with isolated intraretinal fluid (HR, 2.05; 95% CI 1.929 to 4.520; p=0.045) at presentation. Logistic regression analysis showed that type 3 choroidal neovascularisation (OR, 0.090; 95% CI 0.021 to 0.382; p=0.001), thinner choroid (OR, 0.993; 95% CI 0.988 to 0.998; p=0.004) and absence of macular atrophy (OR, 0.233; 95% CI 0.065 to 0.839; p=0.026) at baseline increased the likelihood of achieving ER.

Conclusion

ER is achievable in 9.2% of patients under PRN therapy for nAMD. At presentation with nAMD, anatomical features on retinal imaging may predict the likelihood of achieving ER and a shorter time to achieve ER.

Purpose

To determine the proportion of treatment-experienced eyes with exudative age-related macular degeneration successfully treated with every-4-week aflibercept that can be kept dry on fixed every-8-week aflibercept injections (maintenance).

Methods

In this retrospective chart review, we evaluated our cohort of patients treated with a treatment paradigm for CNV in AMD. Initially, patients were treated with bevacizumab or ranibizumab and switched to every-4-week aflibercept when therapeutic responses were not durable or were suboptimal. Maintenance every-8-week therapy was initiated when the retina was completely dry on every-4-week aflibercept therapy. The primary outcome measure was recurrence of exudation on optical coherence tomography (OCT) during maintenance.

Results

Thirty-six eyes of 31 consecutive patients with median age of 79 years (range, 65-89) were included. Maintenance was started after a median of 34 (range, 8-88) injections. Recurrence was observed in 20 eyes (55%). Of these, 11 eyes (31%) reactivated at 8 weeks. Median time to failure of maintenance schedule was 40 weeks by Kaplan-Meier analysis. Baseline demographic and anatomic characteristics were not associated with failure of maintenance schedule.

Conclusion

In treatment-experienced eyes that respond completely to every-4-week aflibercept, maintenance therapy with every-8-week injections can only temporarily maintain anatomic success with the majority of eyes developing recurring activity. This regimen fails early in one third of eyes and has a median effective duration of 40 weeks. Aflibercept appears to be inadequate to maintain control of exudation in most eyes in at least half of eyes undergoing long-term therapy.

Purpose

To assess early retinal microvascular and functional changes in diabetic patients without clinical evidence of diabetic retinopathy with optical coherence tomography angiography and central visual analyzer.

Methods

This was an observational case-control study of diabetic patients without diabetic retinopathy and nondiabetic controls. Patients underwent optical coherence tomography angiography imaging and visual acuity testing using the central visual analyzer. The foveal avascular zone area and the capillary density in the superficial and deep capillary plexuses were measured manually by a masked grader.

Results

Sixty eyes from 35 diabetic patients were included in the study group, and 45 eyes from 31 nondiabetic patients were included in the control group. The foveal avascular zone area was not significantly different between the diabetic group and controls (both P > 0.05). The mean capillary density in the deep capillary plexus was significantly lower in diabetic eyes compared with control eyes (P = 0.04). The mean visual acuity in all central visual analyzer modules was significantly decreased in diabetic patients compared with controls (all P < 0.05).

Conclusion

Optical coherence tomography angiography was able to detect retinal microvascular changes in the deep capillary plexus, and the central visual analyzer showed signs of decreased visual acuity under conditions simulating suboptimal contrast and glare in diabetic patients without diabetic retinopathy.

Purpose

The purpose of this study was to evaluate the ability to align two types of retinal images taken on different platforms; color fundus (CF) photographs and infrared scanning laser ophthalmoscope (IR SLO) images using mathematical warping and artificial intelligence (AI).

Methods

We collected 109 matched pairs of CF and IR SLO images. An AI algorithm utilizing two separate networks was developed. A style transfer network (STN) was used to segment vessel structures. A registration network was used to align the segmented images to each. Neither network used a ground truth dataset. A conventional image warping algorithm was used as a control. Software displayed image pairs as a 5 × 5 checkerboard grid composed of alternating subimages. This technique permitted vessel alignment determination by human observers and 5 masked graders evaluated alignment by the AI and conventional warping in 25 fields for each image.

Results

Our new AI method was superior to conventional warping at generating vessel alignment as judged by masked human graders (P < 0.0001). The average number of good/excellent matches increased from 90.5% to 94.4% with AI method.

Conclusions

AI permitted a more accurate overlay of CF and IR SLO images than conventional mathematical warping. This is a first step toward developing an AI that could allow overlay of all types of fundus images by utilizing vascular landmarks.

Translational relevance

The ability to align and overlay imaging data from multiple instruments and manufacturers will permit better analysis of this complex data helping understand disease and predict treatment.