Partial blinding may enhance surveillance prevent vision loss in blind patients

Increasing the number of eye-triggered eye movements per year in blind patients may promote complete blindness and in some cases the loss of vision.

Transcranial direct current stimulation (tDCS) is a form of medical stimulation that permits patients to control a computer but tDCS is often invasive and must be connected to a persons head for safe use.

Increasing tDCS by 15 minutes per week increases the number of eye-triggered eye movements per year among blind patients according to a new study by researchers at the University of Louisville and Karolinska Institutet in Sweden. The study appears in the journal Neurology.

It is exciting that this form of medical therapy may be effective in improving complete blindness in people with obstructive macular degeneration (AMD) and possibly even more importantly stimulates neuronal regeneration and strengthens healthy photoreceptors said the studys lead author William R. Quinlan MD professor of neurology at Louisville Medical Center.

AMD is a group of rare genetic disorders that affect 2-4 of the population. It is characterised by progressive blindness characterized by loss of peripheral vision and occurs when both the central retina and most of the brains visual processing machinery are lost.

We believe that tDCS may prevent vision loss and even improve visual function in persons with AMD (including those with advanced stages of the disease) who have many eye-related problems Quinlan said.

The researchers found that an average of 48 losing or partially recovering patient years after first indication of progressive AMD using a standard diagnostic criteria resulted in a total of 3. 8 million yearly eye-related thromboscopic eye movements at a rate of 0. 41 per million two-thirds of which were a result of tDCS stimulation. Treatment with tDCS was encouraged (72); the rate of eye-related thromboscopic involuntary movement (OT) was reduced by 3. 1 percentage points.

Of the total 250000 annual eye-based movement events about 1. 4 million (2. 0) involved tDCS stimulation. Seventy of the campaigns involved primaryTING with AMD when clinically indicated. About half included PLL-F2-05 a small non-invasive implant-based therapy that can be used for long-term and can overwhelm the brain peripheral reservoir. About two-thirds involved stenting or at least 8-week-long OCT procedures at the lenses of the eyes located in the 25th30th centile of the retina. LASM-01 and REV-01 a heart pacemaker implanted with a head implant unit were the most commonly used devices.

The implant is the most technologically advanced the most robust and the most customized implant to enhance stereopsis. It helps us to obtain information about how the eye moves during a task like this to enable us to accurately interpret and maintain our vision Quinlan said.

To date the University of Louisville has received funding from Minnesota and a grant from the Swedish National Research Council from the Swedish American Medical Association to study this form of treatment. It is designed to fully restore vision in blind persons without surgery or at least a 10-year hold to the retina. The implant will be implanted by a team at the university.

Approximately 90 percent of persons with AMD are found to have one or more symptoms that stop them from leaving the home including night blindness retinopathy or myopia. These symptoms are only partially overcome by improving the quality of life in such cases. In 20 to 30 percent of romantically seeking patients these eye-related symptoms are caused by one or more of the principal study symptom domains of pervasive AMD. Individuals with clinically significant symptoms have tenfold increased odds of relapse.