Prevalence of outer retinal tubulation in eyes with choroidal neovascularization

Abstract

BackgroundOuter retinal tubulations (ORTs) are branching tubular structures located in the outer nuclear layer of the retina. The goal of this study is to determine the prevalence of ORTs observed in eyes with choroidal neovascularization (CNV) undergoing treatment with anti-angiogenic intravitreous injection (IVI) with anti-VEGF (vascular endothelial growth factor) at the Ophthalmology Department of a tertiary hospital in São Paulo, Brazil.MethodsThis is a descriptive study based on medical charts and Spectral-domain Optical Coherence Tomography (Sd-OCT) scans of 142 patients (158 eyes) treated between 2012 and 2014 with IVI of anti-VEGF for CNV. The patients’ data was analysed according to age, gender, pathology, presence of ORTs, and best corrected visual acuity (BCVA). Patients with and without ORTs were compared according to the last BCVA obtained using Chi square corrected by the Yates factor.ResultsORTs were found in a total of 40 out of 158 eyes (25.31 %) with CNV; in 33 out of 119 eyes (27.7 %) with neovascular age-related macular disease (AMD); in 5 out of 8 eyes (62.5 %) with neovascular angioid streaks; and in 2 out of 12 eyes (16.67 %) with myopic neovascular membranes. Most patients with ORTs had BCVA worse than 20/200, significantly worse BCVA than patients without ORTs.ConclusionsRecent studies have considered that the presence of ORTs is indicative of a photoreceptor degeneration process and may represent a final stage of multiple retinal degenerative pathologies. The prevalence of ORTs in eyes with CNV has not been well described, especially when considering the Brazilian population treated in a public health care system. In our study, ORTs were observed in only three different pathologies: neovascular AMD, neovascular angioid streaks and myopic neovascular membranes. The correct recognition of ORTs is fundamental for its differentiation from intraretinal cysts, for the latter is related to the activity of neovascular diseases, and usually guides anti-angiogenic therapy. We conclude that ORTs have a high prevalence in the population studied, and their correct identification presents relevant therapeutic implications.

Fluorescence Lifetime Imaging Ophthalmoscopy (FLIO) in Patients with Choroideremia

“… 48 In OCT imaging, ORTs are round, hyporeflective spaces with hyperreflective borders located in the outer nuclear layer, as seen in Figure 7 . 44 We found that ORTs were most prevalent in hypofluorescent areas in FAF intensity and had both short and long FLIO lifetimes; however, ORTs also localized in hyperfluorescent areas. Examples of these findings can be seen in Figure 8 .…”

“…ORTs typically represent final stages of advanced retinal diseases such as AMD, cone dystrophy, Stargardt disease, pattern dystrophy, CHM, and other inherited retinal diseases. 43 , 44 ORTs accumulate as a result of retinal deterioration, where cellular debris aggregates in a tubular fashion to protect the RPE from further atrophy. 43 , 45 , 46 It has been reported that ORT formation occurs due to insufficient structural support of the RPE and choroid, with highly atrophic areas having numerous and longer ORTs and RPE islands having distinctly smaller and stabilized ORTs.…”

Outer retinal tubulations in central serous chorioretinopathy associated with choroidal neovascularisation

“…Another study demonstrated ORT in 27.7% of eyes with neovascular AMD (33 out of 119 eyes). 13 In a post hoc analysis of the comparison of treatment trial (CATT) for AMD, 64 of 368 eyes (17.4%) were noted to have ORTs at the end of 2 years. 14 ORTs were noted in 20% of eyes with Best disease and 3% of eyes with retinitis pigmentosa.…”

Development of Macular Atrophy in Patients with Wet Age-Related Macular Degeneration Receiving Anti-VEGF Treatment

“…Outer retinal tubulations (ORTs) are a branching tubular structure located in the outer retinal layer, with hyper-reflective borders that enclose a hypo-reflective center; they are a common feature in advanced disease, present in about 30% of patients with wAMD [121, 122]. ORTs are an important predictor of poor visual outcomes [123] and are associated with neovascular fibrosis and vision loss [121, 124].…”