Dr. Grossman’s Blog

Painting of a retina with uveitis by Howard Bartner via history.nih.gov

As part of our Vision Wellness Protocol to prevent all eye diseases, we always recommend that you stop smoking.  Here’s another reason to quit: people who smoke are more than two times as likely to develop uveitis than non-smokers.

Uveitis is an inflammation of the inner layer of the eye that can result in severe and permanent vision loss. In addition, uveitis can lead to other ocular complications including glaucoma, cataracts, or retinal damage all of which can severely damage the eyes. Early detection and treatment is necessary to reduce the risk of permanent vision loss.

Uveitis can be a result of trauma to the eye, but often it is not possible to trace its cause.  But, as this study suggests, we may be able to add smoking to the list.  According to study author Nisha Acharya, MD, “Cigarette smoke includes compounds that stimulate inflammation within the blood vessels, and this may contribute to immune system disruption and uveitis.”

Source:http://www.sciencedaily.com/releases/2010/03/100301135215.htm

For more on uveitis, including how to prevent and treat it naturally, visit our website.

Researchers from the University of Washington and the University of Florida have used gene therapy to cure two monkeys of color blindness. 

An article published online in the journal Nature discusses the potential for this type of gene therapy to treat adult vision disorders involving cone cells, including color blindness and other retinal diseases.

Color blindness is an inherited disorder caused by a single defective or absent gene.  Jay Neitz, a professor of ophthalmology at the University of Washington (U.W.) School of Medicine and senior study author and his wife Maureen Neitz, also in the U.W. ophthalmology department, have identified this particular gene and developed a working virus vector to carry a functional copy of it.

Researchers injected the gene-carrying virus into the monkeys’ eyes. In about 20 weeks the monkeys attained full color vision and have shown no harmful side effects.

Color-blindness is a common genetic disorder, affecting more than 3.5 people in the United States, including about 8% of Caucasian men, leaving them unable to distinguish between red and green hues.

The research team hopes to be able to translate the findings into clinical trials for humans. The team used human genetic material in the monkeys in the interest of expediting future research.

SOURCE:  Colour blindness corrected by gene therapy, Nature doi:10.1038/news.2009.921

The 73-year-old, known only as Ron, had the experimental surgery seven months ago at London’s Moorfields Eye Hospital and is now able to see flashes of light, follow white lines on the road, and sort grey and black socks.

The eye known as the Argus II, which was developed by US company Second Sight, uses a miniature camera mounted on glasses to transmit images to the back of the eye.

An “artificial retina” consisting of an array of electrodes sends messages along the optic nerve to the brain.

So far 18 patients around the world have undergone the surgery as part of trials and Ron, who lost his sight in his forties due to the hereditary eye disorder retinitis pigmentosa, was one of three patients to have the device fitted at the London hospital.

As he starts to get use to the device his life will be transformed even more as he gradually learns how to use the artificial eye.

He said: ‘For 30 years I’ve seen absolutely nothing at all, it’s all been black – but now light is coming through.

‘It gives me grades of bright light to black and anything in between. I can actually sort out white socks, grey socks and black socks.’

A new study shows that when people with retinal disease such as macular degeneration use a peripheral part of their retina to compensate for their loss of central vision, their brain appears to compensate by reorganizing its neural connections.

Macular degeneration (MD) causes a progressive loss of central visual.  To cope with this, MD patients often start to focus using a functional retinal area in the periphery of their area of vision. This use of a new area of focus may foster cortical reorganization.

Scientists at the Georgia Institute of Technology used functional magnetic resonance imaging (fMRI) to measure brain activity in participants as they performed a series of tests designed to visually stimulate their peripheral regions.  It was determined that when the participants visually stimulated the peripheral retinal locations they increased brain activity in the same areas of the visual cortex that are normally activated when healthy patients focused on objects in their central visual field.

Study authors believe that large-scale cortical reorganization of visual processing occurs in humans in response to retinal disease.  While several other studies have suggested that the brain can reorganize itself, this is the first study to show that this reorganization in patients with retinal disease is related to patient behavior.

Researchers are currently analyzing how long this reorganization takes and whether it can be assisted with low-vision training.

Learn more about macular degeneration

Read about eye exercises for vision fitness

SOURCE: Reorganization of visual processing is related to eccentric viewing in patients with macular degeneration, Schumacher, et al, Restorative Neurology and Neuroscience, Volume 26, Number 4-5, 2008, 391 – 402.