Saving your sight

Just a few days ago the UN member countries marked the World Sight Day, an annual day of awareness to focus global attention on blindness, visual impairment and rehabilitation of the visually impaired. The event is held on the second Thursday in October.

World Sight Day is observed around the world by all partners involved in preventing visual impairment or restoring sight. It is also the main advocacy event for the prevention of blindness and for “Vision 2020: The Right to Sight”, a global effort to prevent blindness created by WHO and the International Agency for the Prevention of Blindness.

Sight is life’s or Nature’s Greatest Gift. Of the five senses, it is the most important one. But millions of people either do not have it already or are gradually losing it.

Visual impairment is a major global health issue: the preventable causes are as high as 80 percent of the total global numbers. That is indeed a cause for concern. Millions are going blind needlessly either because they had not taken preventive measures or because they have no access to proper medical care. But individual countries must launch effective programs to fight blindness together with the WHO which has several “far-sighted” programs in this regard.

These diseases or groups of diseases which have effective known strategies for their elimination, make up the targets of the WHO Global Initiative to Eliminate Avoidable Blindness, “Vision 2020: The Right to Sight”, which aims to eliminate these causes as a public health problem by the year 2020.

Cataract, onchocerciasis, and trachoma are the principal diseases for which world strategies and programs have been developed. Similar programs have been designed for glaucoma, diabetic retinopathy, uncorrected refractive errors, and childhood blindness. The message is that most forms of blindness are preventable. This is a message that should reach far and wide, possibly through the electronic media. Every day, not just the World Sight Day and the White Cane Day, should be a ‘Save Your Sight’ day. Our eyes deserve more care than we think.

Implants

However, preventing blindness is just one part of the story. It is equally important to try to reverse blindness or restore sight to those who are blind from birth due to congenital defects. Scientists are making vast strides in this arena as well.

The BBC News reported on Friday that two blind British men have had electronic retinas fitted. Chris James, 54, and Robin Millar, 60, took part in a clinical trial coordinated by Oxford University and funded by the National Institute of Health Research.

Both men have retinitis pigmentosa, a rare hereditary condition that causes gradual deterioration of the light-detecting cells in the retina, which can lead to blindness. The electronic retinas are implants containing light detectors designed to replace the lost light-detecting cells.

Immediately following the procedures, when the implants were switched on, both men were able to detect light and are now beginning to use their restored vision.

This early success in these two patients raises hope for the treatment of retinitis pigmentosa, which is currently incurable. Up to 10 further patients with retinitis pigmentosa will now be treated as part of this clinical trial.

The retinal implants were developed by Retina Implant AG in Germany to treat people with retinitis pigmentosa. Each implant contains a microchip containing 1,500 tiny electronic light detectors. During the trial, the implant was placed beneath the retina at the back of the patient’s eye. The patient’s optic nerve was then able to pick up electronic signals coming from the microchip.

What makes this unique is that all functions of the retina are integrated into the chip. It has 1,500 light-sensing diodes and small electrodes that stimulate the overlying nerves to create a pixellated image. Apart from a hearing aid-like device behind the ear, you would not know a patient had one implanted.

This is indeed the future of sight restoration. These are not inexpensive, but costs should come down in the next decade.

There is a lot of buzz surrounding such “Bionic Eyes” being tested by hospitals and optical companies around the world. In another such move, US surgeons on Tuesday unveiled a new, bionic tool for treating macular degeneration: a miniature telescope, smaller than a pea, that is implanted directly into the eye.

The mini-telescopic device is barely detectable, but a close look at a patient with the implant reveals a slightly luminescent spot where the pupil would be. The miniature telescope represents a breakthrough treatment for a casualty of old age, akin to the hip and knee replacements that have now become commonplace.

Vision

There is no doubt that in 20-30 years, it will be possible to give at least a semblance of colour vision to those who have lost it either from birth or through disease.

While that will be the ultimate breakthrough, there is nothing quite like saving the sight you already have.

A visit to an eye hospital or eye surgeon is all it takes to find out whether your vision is getting impaired in some way.

Do it while the light lasts - otherwise you may have to spend the rest of your life in the dark.