Session Title: Quick Fire Free Paper Session 04
Session Date/Time: Sunday 29/09/2013 | 11:00-13:00
Paper Time: 11:00
Venue: Hall C (Level 1)
First Author: A.Caimi ITALY
Co Author(s): A. Caimi G. Staurenghi
To assess differences between imaging modalities in visualizing retinal thermic effect secondary to laser photocoagulation.
Luigi Sacco Hospital - University of Milan
Patients affected by pre-proliferative or proliferative diabetic retinopathy and ischemic retinal vein occlusion needing retinal photocoagulation were enrolled in the study. The presence of retinal ischemia was assessed with fluorescein angiography. Exclusion criteria were the presence of hemovitreous and any diopters opacity obstructing laser treatment. After enrollment patients underwent laser photocoagulation with a navigated system (NAVILAS®, OD-OS, Teltow, Germany). The system allowed recording the exact location and delivered energy for each single laser spot. For the purpose of the study a grid of laser spots was applied in correspondence of extra-macular ischemic areas. Power started from 50 mW and was increased of 10 mW every two spots in the grid till reaching one of the following:1) intense whitening of the retina; 2) power equal to 300 mW; 3) pain complaint. Thereafter patients underwent examination with different imaging modalities: NAVILAS® color photography; confocal infrared, red-free, autofluorescence, multicolor, spectral-domain optical coherence tomography (SD-OCT) (Spectralis, Heidelberg Engineering, Germany). Images from each single modality was analyzed by two operators and the total number of visible spots were assessed. Comparison between the imaging modalities was analyzed with a Friedman test.
A total of six patients were enrolled in the study, 3 males and 3 females. Mean age was 73, mean best-corrected visual acuity was 20/60. An average of 26 ± 6.8 spots was applied. Mean maximum power was 230 ± 46.9 mW. There was a statistical difference between the different imaging modalities in visualizing laser spots (p < 0.001). SD-OCT was the most sensible modality, with an average of 54 ± 9% of visualization of delivered spot. NAVILAS® color photography (39 ± 13%), Spectralis multicolor (35 ± 9%) and redfree (37 ± 6%) had similar results. Infrared (17 ± 7%) and autofluorescence (24 ± 11%) showed a lower rate of spot visualization.
SD-OCT is able to show retinal alterations during laser retinal coagulation treatment even in absence of visualization with other imaging modalities.