Session Title: Imaging II
Session Date/Time: Sunday 29/09/2013 | 08:00-10:00
Paper Time: 08:32
Venue: Hall G1 (Level 2)
First Author: M.Saleh FRANCE
Co Author(s): G. Debellemani?re M. Bidaut Garnier P. Tumahai M. Meillat
To image the macular cone photoreceptors in eyes with anatomically successful repair of rhegmatogenous retinal detachment (RD) and in healthy fellow eyes using an Adaptive Optics (AO) Fundus Camera and to correlate the results to the clinical outcomes.
Hospital-based cross-sectional study
Patients operated for macula-off RD were imaged 6 weeks after the surgery using the RTX-1 Adaptive Optics device from Imagine eyes™ (Orsay, France). Images were analysed using AO Detect v.0.1, the proprietary software of the device. Cone density (cells/mm2), spacing between cells (µ), and percentage of cones with 6 neighbors calculated on Voronoï diagrams, were measured 1° nasally and temporally from the fovea in the operated eyes and in the normal fellow eyes. Visual acuity (logMAR), refraction, axial length (mm) and thickness of the photoreceptor inner and outer segment junction (IS/OS) line together with retinal thickness imaged by SD-OCT were also measured.
Eighteen patients were studied. The parafoveal cone density was decreased at the 6 week visit in eyes operated for RD (mean±SD: 14345.9± 4160.9/mm2) compared to fellow eyes (20588± 2579.9/mm2) (Wilcoxon matched pairs test P=0.0004). There was also an increase in cone spacing (10.6 ±2.7 vs. 8.11 ±1.0µ, respectively, p< 0.0001). The Voronoï and nearest-neighbor analysis revealed a reduction in the percentage of cones with 6 neighbors (36.6±4.6 vs. 5.4± 45.4%, P=0.0015). The IS/OS line thickness, thinner in the operated eyes, was correlated to the cone density measured by AO in the same area (Spearman r=0.57, p<0,001). Best corrected visual acuity was significantly correlated to cone density and inversely correlated to intercone spacing, and in a lesser proportion to percentage of cones with 6 neighbors (Spearman r: 0.83, -0.83 and 0.54, respectively, p<0,001).
Adaptive Optics allowed in vivo imaging of the macular photoreceptors in eyes operated for RD. There was a decrease in the cone density after RD with an estimate loss of one-third of cones in comparison with fellow eyes. Visual acuity was highly correlated with the parafoveal cone density, with the cone spacing and with the integrity of the cone mosaic. AO could represent a valuable prognostic tool after RD surgery.