CORRELATION OF OUTER RETINAL TUBULATIONS AND CHORIOCAPILLARIS FLOW SIGNAL DEFICITS SURROUNDING GEOGRAPHIC ATROPHY

Assessment of Retinal Capillary Dropout after Transcatheter Aortic Valve Implantation by Optical Coherence Tomography Angiography

Transcatheter aortic valve implantation (TAVI) is an alternative to open heart surgery in the treatment of symptomatic aortic valve stenosis, which is often the treatment of choice in elderly and frail patients. It carries a risk of embolic complications in the whole cerebral vascular bed, which includes the retinal vasculature. The main objective was the evaluation of retinal emboli visible on optical coherence tomography angiography (OCTA) following TAVI. This is a prospective, single center, observational study enrolling consecutive patients over two years. Patients were assessed pre- and post-TAVI. Twenty-eight patients were included in the final analysis, 82.1% were male, median age was 79.5 (range 52–88), median BCVA was 82.5 letters (range 75–93). Eight patients (28.6%) presented new capillary dropout lesions in their post-TAVI OCTA scans. There was no statistically significant change in BCVA. Quantitative analysis of macular or peripapillary OCTA parameters did not show any statistically significant difference in pre- and post-intervention. In conclusion, capillary dropout lesions could frequently be found in patients after TAVI. Quantitative measurements of macular and peripapillary flow remained stable, possibly indicating effective ocular blood flow regulation within the range of left ventricular ejection fraction in our cohort.

Acute and subacute macular and peripapillary angiographic changes in choroidal and retinal blood flow post-intravitreal injections

Whether post injectional acute intraocular pressure (IOP) increase is associated with decreased peripapillary and macular perfusion is still under debate. Here, we investigated early changes in the choroidal and retinal blood flow using OCTA imaging in a cohort of patients undergoing anti-VEGF intravitreal injections (IVI) for macular edema following retinal vein occlusion and diabetic retinopathy. In this prospective single-center, observational study, the pre- and post-IVI changes in retinal perfusion were examined via assessment of vessel length density (VLD) and vessel density (VD) in deep and superficial capillary segmentations (DCP and SCP), foveal avascular zone (FAZ) in SCP, as well as flow signal deficits in the choriocapillaris segmentation. Mean IOP significantly changed over the study course (p = 0.000; ANOVA). Measurements at 5 min post-IVI (33.48 ± 10.84 mmHg) differed significantly from baseline (17.26 ± 2.41 mmHg, p = 0.000), while measurements from one day, one week, and one-month post-IVI did not (p = 0.907, p = 1.000 and p = 1.000 respectively). In comparison to baseline, no changes in OCTA parameters, including FAZ, VD, VLD, and FV, were detected 5 min post-IVI. No significant alterations in OCTA parameters were observed during study course. Increased IOP spikes were detected post-IVI; however, no potential permanent ischemic retinal damage was suspected.

[Morphology of outer retinal tubulations in the outcome of exudative age-related macular degeneration according to optical coherence tomography angiography]

Outer retinal tubulation (ORT) develops in the later stages of age-related macular degeneration (AMD). It is associated with low visual acuity, severe loss of photoreceptors, choroidal neovascularization (CNV), and geographic atrophy. Despite the frequent detection of ORTs by optical coherence tomography (OCT), their role in the process of outer retinal atrophy and degenerative changes in photoreceptors remains undetermined.

PURPOSE

To investigate the evolution of ORT in patients with exudative and disciform-stage CNV.

MATERIAL AND METHODS

The retrospective study included 340 patients with AMD, among them 235 (69%) women and 105 (31%) men with mean age of 76±7.4 years; in all, the analysis involved 267 eyes with dry AMD and 174 eyes with CNV: 92 eyes - with exudative AMD, 82 eyes - with disciform-stage disease). In addition to standard OCT, all patients underwent OCT-angiography (OCTA). In 10 cases, patients with exudative AMD were followed up after intravitreal injections of Aflibercept.

RESULTS

ORTs were detected in 37 eyes of 32 patients (26%), all of them with CNV: 13 eyes with exudative AMD (group 1) and 24 eyes with disciform scar (group 2; p=0.013).

The groups were similar in the type and morphology of ORTs. The most common were closed, i.e. fully formed ORT (92% of cases in group 1, and 88% in group 2). Destruction of the ellipsoid zone associated with ORT was observed in both groups. In one case, there was an increase in the size of ORT corresponding to the volume of cystic macular edema. Disappearance of ORT was noted only in one of ten patients 3 months after intravitreal injection of Aflibercept, but was not accompanied by visual acuity improvement.

CONCLUSION

Outer retinal tubulations are more common in the later stages of AMD, being an indicator of a deep destructive process in photoreceptors. In exudative AMD, ORTs serve as a predictive marker for poor functional outcomes.

Impact on Visual Acuity in Neovascular Age Related Macular Degeneration (nAMD) in Europe Due to COVID-19 Pandemic Lockdown

This is a retrospective, multicenter study of consecutive patients with nAMD scheduled for a visit and/or a treatment with an intravitreal injection (IVI) during the 3 months before lockdown in the Ophthalmology Departments of six centers of Europe.The study was conducted on 546 patients, of which 55.13% were females, almost 100% of the patients were White/Caucasian race, and 71.53% of the patients presented a type 1 macular neovascularization (NVM). A total of 62.82% of patients (343 patients) that were on scheduled clinic visits and/or intravitreal injection treatment during the 3 months before the quarantine did not attend either to visit or for treatment during the lockdown. The mean number of injections during the lockdown was significantly reduced. This was followed by a significant reduction in the mean best-corrected visual acuity (BCVA) between the 3 months before the lockdown (mean BCVA of 60.68 ± 19.77 letters) and 6 months after lockdown (mean BCVA of 56.98 ± 22.59 letters). Patients with better BCVA before the lockdown and the ones showing neovascular activity were more likely to attend their scheduled visits and/or IVI treatments. The COVID-19 pandemic and the lockdown have led to a decrease in the number of IVI treatments in patients with nAMD, evidencing a significant vision loss at 6 months.

Outer retinal tubulation formation and clinical course of advanced age-related macular degeneration

Outer retinal tubulations (ORT) are a relatively new finding characterizing outer retinal atrophy. The main aim of the present study was to describe ORT development in advanced age-related macular degeneration (AMD) and to assess its relationship with disease’s severity. Patients with advanced AMD characterized either by macular neovascularization or geographic atrophy, showing signs of outer retinal disruption or retinal pigment epithelium atrophy on structural optical coherence tomography (OCT) at the inclusion examination were prospectively recruited. All the patients underwent complete ophthalmologic evaluation, structural OCT scans and fundus autofluorescence imaging. The planned follow-up was of 3-years. Main outcome measures were ORT prevalence, mechanism of ORT formation, mean time needed for complete ORT formation, best-corrected visual acuity (BCVA), definitely decreased autofluorescence (DDAF) area, questionably decreased autofluorescence (QDAF) area, retinal layer thickness, foveal sparing, number of intravitreal injections. We also assessed the possible role of external limiting membrane (ELM) and Müller cells in ORT pathogenesis. Seventy eyes (70 patients) were included; 43 showed dry AMD evolving to geographic atrophy, while 27 displayed the features of wet AMD. Baseline BCVA was 0.5 ± 0.5 LogMAR, decreasing to 0.9 ± 0.5 LogMAR at the 3-year follow-up (p < 0.01). We detected completely formed ORT in 26/70 eyes (37%), subdivided as follows: 20 eyes (77%) wet AMD and 6 eyes (23%) dry AMD (p < 0.01). ORT took 18 ± 8 months (range 3–35 months) to develop fully. We described the steps leading to ORT development, characterized by progressive involvement of, and damage to the photoreceptors, the ELM and the RPE. Eyes displaying ORT were associated with a smaller QDAF area, less retinal layers damage and lower rate of foveal sparing than eyes free of ORT (p < 0.01). We also described pigment accumulations simulating ORT, which were detected in 16/70 eyes (23%), associated with a greater loss of foveal sparing, increased DDAF area and smaller QDAF area at the 3-year follow-up (p < 0.01). In conclusion, this study provided a description of the steps leading to ORT development in AMD. ELM and Müller cells showed a role in ORT pathogenesis. Furthermore, we described a subtype of pigment hypertrophy mimicking ORT, evaluating its clinical utility.