Vision loss caused optic nerve damage previously was considered irreversible. Conducted in Germany randomized placebo controlled double blind multi-center clinical trial (2010-2012) has shown an ability to restore vision for visually impaired patients after 10 sessions of noninvasive alternating current stimulations. Improved eyesight (enlarged visual field and increased visual acuity) associated with positive impact on vision related quality of live as reading, mobility or orientation.
Alternating Current Stimulation Restore Vision
After Optic Nerve Damage
Background. Vision loss after optic neuropathy is considered irreversible. Here, repetitive transorbital alternating current stimulation (rtACS) was applied in partially blind patients with the goal of activating their residual vision.
Methods. We conducted a multicenter, prospective, randomized, double-blind, sham-controlled trial in an ambulatory setting with daily application of repetitive transorbital alternating current stimulation (n = 45) or sham-stimulation (n = 37) for 50 min for a duration of 10 week days. A volunteer sample of patients with optic nerve damage (mean age 59.1 yrs) was recruited. The primary outcome measure for efficacy was super-threshold visual fields with 48 hrs after the last treatment day and at 2-months follow- up. Secondary outcome measures were near-threshold visual fields, reaction time, visual acuity, and resting-state EEGs to assess changes in brain physiology.
Results. The repetitive transorbital alternating current stimulation-treated group had a mean improvement in visual field of 24.0% which was significantly greater than after sham-stimulation (2.5%). This improvement persisted for at least 2 months in terms of both within- and between-group comparisons. Secondary analyses revealed improvements of near-threshold visual fields in the central 5° and increased thresholds in static perimetry after repetitive transorbital alternating current stimulation and improved reaction times, but visual acuity did not change compared to shams. Visual field improvement induced by repetitive transorbital alternating current stimulation was associated with EEG power-spectra and coherence alterations in visual cortical networks which are Alternating Current Stimulation for Vision Restoration interpreted as signs of neuromodulation. Current flow simulation indicates current in the frontal cortex, eye, and optic nerve and in the subcortical but not in the cortical regions.
Conclusion. repetitive transorbital alternating current stimulation treatment is a safe and effective means to partially restore vision after optic nerve damage probably by modulating brain plasticity. This class 1 evidence suggests that visual fields can be improved in a clinically meaningful way.
More information: „Alternating current stimulation for vision restoration after optic nerve damage: a randomized clinical trial,“ by Carolin Gall, Sein Schmidt, Michael P. Schittkowski, Andrea Antal, Géza Gergely Ambrus, Walter Paulus, Moritz Dannhauer, Romualda Michalik, Alf Mante, Michal Bola, Anke Lux, Siegfried Kropf, Stephan A. Brandt, Bernhard A. Sabel, published by PLOS ONE.