Abstract
Purpose: :
To evaluate the changes of fixation pattern, retinal sensitivity using microperimetry in low vision patients affected by macular degeneration submitted to rehabilitative program by means of IOL VIP System (Intraocular Lens for Visually Impaired People, Subvision, Milano, Italy).
Methods: :
11 eyes of 7 patients (4M, 3F), mean age 70.1yrs ± 12.46SD (range from 55 to 81), affected by macular degeneration, were submitted to IOL VIP implantation (3 in both eyes; 5 in one eye). Mean preoperative best corrected visual acuity (BCVA) was 0.06 ± 0.08SD. The system consists in both rehabilitative and surgical procedure studied to improve vision capabilities. The practice with a special computer software, performed before and after surgery to train the PRL, allows patients to use IOL VIP implant. The surgical technique consists in a phacoemulsification of cataract followed by implantation of two IOLs: one in the bag and one in the anterior chamber. These two IOLs realize a Galilean telescopic system with 1.3 X magnification. Using microperimetry (MP1, Nidek Technologies, Tokyo, Japan), the position and stability of PRL and the retinal sensitivity property were studied. The changes of PRL’s stability and position and improvement of BCVA were analyzed and compared at the time 0 (pre-rehabilitation), at time the 1 (after software PRL training) and at time 2 (3 months after surgery). Statistical analysis was made using Wilcoxon Signed Ranks Test in SPSS 12.0 Statistical Program (α < 0.05).
Results: :
All treated patients reached an improvement in the visual acuity (post-surgery BCVA was 0.145 ± 0.19SD), stability and better positioning of PRL (fixing closer scotoma’s edge). The best fixation stability, location of PRL and BCVA were achieved after the complete procedure (p=0.003); instead, the PRL training alone allowed lower but anyway significant changes (p= 0.041). No significant changes of the retinal sensitivity and of scotoma dimensions were seen during the entire rehabilitative program.
Conclusions: :
IOL VIP System seems to be a safe and effective combined therapeutic technique for central low vision patients. Microperimetry highlights the effect and the progress of the rehabilitation procedure.
Keywords: low vision • macula/fovea • clinical (human) or epidemiologic studies: systems/equipment/techniques