Session Title: Free Paper Session 22: AMD V
Session Date/Time: Sunday 10/09/2017 | 08:00-09:30
Paper Time: 08:36
Venue: Room 115
First Author: : A.Oishi JAPAN
Co Author(s): : P. Fang S. Thiele F. Holz T. Krohne
A retinal pigment epithelium (RPE) tear represents a serious complication in the natural history and during anti-VEGF-therapy of neovascular age-related macular degeneration (nAMD). Visual outcome of RPE tears is highly variable rendering the assessment of treatment effects challenging. Likewise optimal treatment for the condition is yet to be established. Recent advances in optical coherence tomography enabled objective measurement of outer nuclear layer (ONL) thickness, which may serve as a marker of retinal integrity. The purpose of this study was to determine longitudinal changes of ONL thickness in patients with RPE tears secondary to nAMD and their potential functional impact.
Retrospective observational case series in one institution.
We included patients with RPE tears who attended our AMD clinic during April 2009 and March 2015 and who were followed with serial SD-OCT volume scans (Heidelberg Engineering, Heidelberg, Germany). All patients underwent intravitreal injection of anti-VEGF agents as needed. SD-OCT scans at first diagnosis of tear (baseline) and after 12 months were analyzed. ONL was segmented with an automatic program followed by manual correction if necessary. Average ONL thickness was measured in a two by two-degree grid applied on a 12 by 20-degree area. Each grid box was classified into three groups: inside the tear area (area I), covering the border of the tear (area B), and outside the tear area (area O). Change of ONL thickness was evaluated separately for these three areas. We also explored several factors for their association with ONL thinning including age, tear area, maximum pigment epithelium detachment height prior to tear development, presence of reticular pseudodrusen, number of anti-VEGF treatments after tear development, and the duration of persistent subretinal fluid.
Twenty-six eyes of 22 patients (14 males and 12 females, mean age 78.8 years) were included. They were followed with mean interval period of 1.6 months and received 7.3 anti-VEGF injections within the first year after RPE tear development. Thinning of ONL was found in all the investigated areas (P < 0.01, respectively). The time-course of ONL thinning in each area was well approximated with a linear regression model (R2 = 0.987 for area I, 0.931 for area B, and 0.999 for area O, respectively). Among the investigated factors, larger tear area was associated with greater ONL thinning outside the tear area (standardized ß = -0.37, P = 0.030), and younger age was associated with greater ONL thinning inside the tear area (standardized ß = 0.37, P = 0.041). Interestingly, five eyes showed little or no measurable ONL thinning (less than 2 µm) even in area I. What factors contributed to the preservation of ONL remained unclear.
Following an RPE tear, thinning of ONL occurs in the area devoid of RPE and also in adjacent areas. Thinning of ONL progresses in a linear fashion through one year after development of RPE tear but the thinning can be minimal in some eyes. Few factors were predictive for the degree of ONL thinning. These results provide new insight in disease progression of this particular subphenotype of nAMD.