Tag Archives: blindness

Stem-cell contacts restore eyesight

eyeStill wondering whether there’s a down-to-earth application for stem cell science that doesn’t involve tabloid-rousing research ideas like chimeric embryos? Well, get this for a simple, elegant and incredibly useful deployment: wearing contact lenses primed with stem cells can restore eyesight in people with corneal damage.

The idea stemmed from the observation that stem cells from the cornea (the thin, transparent barrier at the front of the eye) stick to contact lenses. Employing three patients who were blind in one eye, the researchers obtained stem cells from their healthy eyes and cultured them in extended wear 1 day acuvue moist for astigmatism for ten days. The surfaces of the patients’ corneas were cleaned and the contact lenses inserted. Within 10 to 14 days the stem cells began to recolonize and repair the cornea.
“The procedure is totally simple and cheap,” said lead author of the study, UNSW’s Dr Nick Di Girolamo. “Unlike other techniques, it requires no foreign human or animal products, only the patient’s own serum, and is completely non-invasive.
Of the three patients, two were legally blind but can now read the big letters on an eye chart, while the third, who could previously read the top few rows of the chart, is now able to pass the vision test for a driver’s license. The research team isn’t getting over excited, still remaining unsure as to whether the correction will remain stable, but the fact that the three test patients have been enjoying restored sight for the last 18 months is definitely encouraging. The simplicity and low cost of the technique also means that it could be carried out in poorer countries.

Brilliant! Now, insert your own joke about George W Bush and myopia here. [image by peasap]

Lasers vs. police helicopters

lasercockpitFollowing on from the news of blinding-laser “friendly fire” incidents in Iraq is this article on the growing problem of green lasers being used against police helicopters in the UK:

An “attack” can come from any of the darkened streets over which the force’s state of the art helicopter India 99 flies at night.

“You can’t miss it. A sharp green beam of light shoots up from the ground, flashing around the helicopter, dazzling anyone on whom it scores a ‘direct hit’,” said Mr Briggs.

The police have had to learn to deal with the attacks — about half of those reported are aimed at their helicopters. In 2003 just three incidents were recorded. Last year there were 207. So far this year, the tally is 76.

The culprits are usually bored youths, who have got hold of a laser pointer and amuse themselves by playing its beam over passing aircraft.

One of those “we are living in the 21st century” moments – idlers attacking police helicopters with lasers…

[image and article from the BBC]

Blinded by the laser light

green_laserIn what won’t be the last instances of laser-related “friendly fire” three US soldiers in Iraq have been hospitalised, and one has been blinded in one eye, by a green dazzling laser:

Since November 2008, a single unit in Iraq “has experienced 12 green-laser incidents involving 14 soldiers and varying degrees of injury. Three soldiers required medical evacuation out of Iraq and one soldier is now blind in one eye,” writes Sgt. Crystal Reidy

[from Wired][image from Wired]

Bionic eye breakthrough

eye_closeUS company Second Sight have developed a bionic eye system that allows a man who has been blind for 30 years to see flashes of light:

He says he can now follow white lines on the road, and even sort socks, using the bionic eye, known as Argus II. It uses a camera and video processor mounted on sunglasses to send captured images wirelessly to a tiny receiver on the outside of the eye.

The Argus II is designed to help sufferers of retinitis pigmentosa, a degenerative eye condition.

[article form the BBC][image from Mazintosh – Fotogranada on flickr]

Eye implants in human trials

Researchers have gone from a 4×4 grid (16 ‘pixels’) in 2004 up to a 60-electrode version that was implanted in two men recently.  While not quite in Geordi Laforge territory, it’s a big step up from complete blindness.  After enough practice, the earlier patients were able to distinguish between eating implements at a dinner table, so it’ll be interesting to see what these guys can do.  The 3rd generation will be designed with about 600 electrodes, and they’re hoping that patients will be able to read.

A camera built into a pair of glasses connects to a processing pack that is carried or clipped onto the belt.  This then beams the image into the retina, turning on electrodes and stimulating the eye.  So far, this will only work for people who have lost vision, not for people who were born blind.

(via DailyTech)