CORTICAL REHABILITATION IMPROVES FUNCTIONAL ABILITY IN NEURO-ADAPTATION FAILURES FOLLOWING MULTIFOCAL IMPLANTS: A RANDOMIZED CONTROLLED TRIAL

Photic phenomena, neuro-adaptation failures are major concerns after MFIOLs. This study evaluated patient-specific, perceptual visual therapy(VPL) regime using Gabor patches (grey level gratings, specific for receptive visual fields) for improving vision & contrast sensitivity function(CSF) in patients not satisfied after MF-IOL implantations.

A single-center, prospective, controlled-randomized study. 

A Prospective, controlled-randomized study. Adults (50-70 yrs) with uneventful MF-IOLs, over 24 weeks post-surgery, BCVA worse than 20/40 with sub-optimal Contrast(CSF), complaining about vision quality, were randomized in a 2:1 ratio into Treatment(G1), in which computer-based perceptual therapy using Gabor patches amidst co-linear flankers was employed & Control(G2) arms. The study had 2 phases (screening + therapy). Mid-training (Post 20 sessions), 40 training sessions, post-therapy follow-up by 6 months were evaluated for improvements in BCVA distance & near (ETDRS) & CSF at spatial frequencies of 3, 6,12,18 CPD with FACT sine wave grating, using Friedman tests for repeated measures.

30 cases were randomized into a 2:1 ratio into treatment and control arms. Subgroup consisted of 16 Trifocals (PanOptix), 14 Bifocals (Tecnis). The average improvement after VPL therapy is 2.5 lines in LogMar in the Treatment arm (p<0.0001), whereas no significant improvements were observed among the controls. Tests for repeated measures showed 83% improvement in Contrast Sensitivity (CSF at spatial freq. of 3,6,12 & 18 CPD) in the Treatment Group(G1, all p<0.0001), whereas no significant improvements were observed amongst the controls.

Sequential, post-operative, patient-specific, cortical stimulation improved vision & CSF in patients with dissatisfied Multi Focal-IOL subjects & acts as proof of concept of improving neural connections at cortical levels. The key to optimizing vision following MF-IOLs lies in training the brain to improve neuroadaptation processes.