Influence of membrane differential filtration on the natural course of age-related macular degeneration - A randomized trial

Purpose: Membrane differential filtration is able to optimize theologic par ameters by eliminating high molecular weight proteins and lipoproteins from the blood. Following the hypothesis that these changes result in an improv ement of the microcirculation, the authors tested the efficacy of membrane differential filtration in improving visual function in patients with age-r elated macular degeneration (ARMD). Methods: Forty patients (40 eyes) were randomized into two groups, The trea tment group was treated five times over a period of 21 weeks. In both group s, 9/20 of the eyes showed subfoveolar subretinal neovascularization. The m ain parameter of the study was visual acuity (VA). Electroretinogram (ERG), electrooculogram, and macular visual evoked potentials were also recorded. Plasma and whole blood viscosity and erythrocyte aggregation were measured . Results: The 20 patients treated repeatedly over a period of 21 weeks showe d a mean improvement of 0.63 lines (SD 1.8) of VA on Early Treatment Diabet ic Retinopathy Study charts. The control group showed a deterioration of 0. 94 lines (SD 1.7) compared to VA at baseline examination. The amplitude of the ERG photopic a-wave and the flicker ERG was significantly increased. Th e theologic parameters were lowered in all treated patients. Conclusion: Repetitive treatment with membrane differential filtration is a ble to improve visual acuity of patients with ARMD and the natural course o f this disease. Several questions arise from the results of this study. Fur ther research will show if it is possible to optimize the selection of pati ents for subgroups with predictive responses through morphologic and functi onal tests and how to create an optimized and individual treatment strategy determined by the quality, intensity, and frequency of treatment sessions.