Abstract
Abstract: :
Purpose:Video biofeedback (VBF) by EEG-controlled modulation of a video presentation improves visual acuity in adult amblyopes. We compare VBF performance and conventional occlusion to answer the following: (a)Does VBF improve VA to a level higher than originally achieved with occlusion? (b)Does VA improve with biofeedback in subjects who did not improve with placebo treatment? (c)What regression levels occur post-biofeedback? Methods:Prior occlusion data from 39 patients was compared with subsequent VBF results to answer (a). 18 patients who were initially allocated to the placebo-controlled group volunteered to receive VBF at the end of the controlled trial. The post-placebo results with VBF were compared with their placebo results to answer (b). Follow-up data after cessation of VBF was available from 24 (11 strabismic, 7 anisometropic and 6 aniso-strabismic) patients. Their VA regression values post-VBF and post-occlusion were compared to answer (c) Results: The results of trial (a) are shown in the table rows 2 and 3, while the results of trial (b) are shown in row 4. Trial (c): Mean VA regression post-occlusion in 39 patients was - 0.19 (SD=0.23) LogMAR after a mean follow-up period of 41.8 (SD=28.9) months, with maximum regression seen in the strabismic group (Mean =0.24, SD=0.27). After a mean follow-up period of 5.1 months after completing VBF, 20/24 patients showed a mean regression of 0.13 LogMAR. The aniso-strabismic category showed more regression (Mean=0.19, SD=0.08) than the strabismic (mean=0.12, SD=0.08) and anisometropic (mean=0.1, SD=0.12) amblyopes. Conclusion:Nearly 60% of our sample population who received VBF reached final VAs that were better than the VAs they had achieved previously with occlusion alone. VBF also improved VA in an amblyopic group that had previously shown minimal response to a placebo version of the procedure. This confirms earlier findings of VBF efficacy. VA regression following VBF cessation suggests the need for either a more prolonged treatment regime or maintenance therapy. Results of trial (a) and (b)
Keywords: 313 amblyopia • 357 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • 620 visual acuity