Abstract
Purpose:
To evaluate the changes in foveal neuro sensorial detachment (NSD), intraretinal cysts and hyperreflective dots (HD) before and two months after dexametasone intravitreal implant for diabetic macular edema.
Methods:
Clinical data and images of optical coherence tomographies (Cirrus HD-OCT, Carl Zeiss Meditec, Dublin, CA) of 35 diabetic patients treated with 700 micrograms dexametasone intravitreal implant (Ozurdex, Allergan, Irvine, CA) were reviewed retrospectively.<br /> Snellen Best corrected visual acuity (BCVA), central subfield thickness (CST), presence and height of foveal NSD and intraretinal cysts were evaluated. Number of HD in all retinal layers were manually counted in a single foveal high definition horizontal scan, before the intravitreal injection and after two months of treatment.
Results:
13 subjects (37.1%) had a NSD that affected the fovea before the injection, with a mean height of 222 (SD 161.5) microns. After treatment, in 4 of them it remained detached, with a mean height of 48 (SD 6.8) microns, and a mean decreased of detachment of 234.8 (SD 24.6) microns (p=0.001).<br /> Before dexametasone implant, 23 (58%) subjects presented with subfoveal intraretinal foveal cysts, with 358 (SD 146.1) microns mean height. In 9 (39.1%) patients they persisted after treatment, but decreased a mean of 100.7 (SD 60.8) microns (p=0.068). 4 of the 12 subjects who originally did not present with foveal cysts, developed them after two months of treatment, with a mean height of 212.5 (SD 91.8) microns.<br /> 30 (85.7%) subjects presented with HD before treatment. In 28 (93.3%) of them, the dots persisted, but decreased from a mean of 13.6 (SD 2) before to a mean of 9.7 (SD 1.2) after injection (p=0.047). In this subgroup, mean CST went from 567 (SD 24) to 336.7 (SD 16.4) microns (p=0.0000). 4 patients of 5 who did not presented with HD before treatment, developed them in the 2 months follow-up visit. However, mean number of spots was 3.3 (1.3). CST decreased from 378.8 (SD 26.4) to 269.8 (SD 19.7) (p=0.001) in this subgroup.
Conclusions:
Foveal NSD and intraretinal cysts completely resolved or significantly improved in all patients after two months of dexametasone injection. HD persisted in 93% of subjects, but significantly reduced in number after treatment. Although some patients developed HD after intravitreal implant, the mean number per scan was low.