Session Title: Quick Fire Free Paper Session 01
Session Date/Time: Thursday 26/09/2013 | 08:30-10:30
Paper Time: 09:10
Venue: Hall G1 (Level 2)
First Author: E.Pedanova RUSSIA
Co Author(s): G. Kachalina
Recent studies have proved the role of inflammation in pathogenesis of age-related macular degeneration (AMD). The applying of Micropulse laser for AMD is theoretically based on the fact, that it modulates the expression of inflammatory cytokines thereby affecting on the early steps of AMD beginning. The purpose of the study is to evaluate the functional and anatomical outcomes of 577 nm Micropulse laser treatment (MLT) for the retinal pigment epithelium (RPE) detachment as an early stage of AMD.
FSBI “The acad. S.N.Fyodorov Eye Microsurgery Complex” of the Minpublhealth of Russia
The study included eight patients (8 eyes) with AMD, accompanied by a dome-shaped RPE detachment, varying in size and height, without neuroepithelium detachment and without evidence of choroidal neovascular membrane. Laser treatment was performed by «IRIDEX IQ 577» laser system (IRIDEX Corp.) with 577 nm yellow wavelength in Micropulse mode. The following settings were applied: spot diameter 100 microm, micropulse 50 microsec, duty cycle 4.7%, train 0.1 sec, the power was adjusted individually after testing (on the average 400-600 mW). Laser spots were applied over the entire surface of detachment and at the distance of 200-300 microm around it. Patients underwent examination at baseline, 1 month and 3 months after MLT. Main outcome measures were: central macular thickness (CMT) measured by “Cirrus” optical coherence tomograph (Carl Zeiss Meditec); best corrected visual acuity (BCVA) measured with Snellen chart in decimal equivalent; and central retinal sensitivity determined by MicroPerimeter 1 (Nidek Technologies).
One month after treatment all patients demonstrated a marked decrease in the height of RPE detachment. Thus, mean CMT decreased significantly (p <0.05) from 520.9 ± 65.3 microm at baseline to 299.4 ± 35.5 microm. Partial regress of RPE detachment was detected in 3 cases. In one case recurrent RPE detachment was observed by 3 months of follow up. Decrease of RPE detachment was accompanied by a significant BCVA improvement. Mean baseline BCVA was 0.4 ± 0.08; 0.75 ± 0.1 at 1 month and remained at the same level at 3 months (0.67 ± 0.1). We have found an unexplained phenomenon of subjective vision impairment at 4 patients with duration of RPE detachment more than a year who had positive anatomical effect. Those patients complained about intensification of "spot" in front of the eye while their BSVA had not worsened. Subjective complaints fully correlated with the microperimetry data. Mean central retinal sensitivity decreased from 11.1 ± 2.9 dB at baseline to 9.1 ± 3.4 dB at 3 months. At the same time other patients have shown the increase of sensitivity from 11.3 ± 3.1 dB to 13.6 ± 2.8 dB.
MLT with yellow 577 nm wavelength and mentioned above parameters is an effective treatment of AMD associated with RPE detachment. Therapeutic effect is especially pronounced anatomically, but the phenomenon of subjective visual impairment requires further studies.