People can soon trade their corrective glasses with shades as Tilganga Institute of Ophthalmology (TIO) is resuming laser surgery for correction of refractive error in a couple of months. [break]People had to travel to India or abroad to avail the facility until now as the hospital had stopped the service for the past three years.
The surgery can correct myopia (inability to see distant objects clearly), hyperopia (difficulty in seeing near objects) and even find a way out for presbyopia (need of reading glasses due to aging). Tilganga will use state-of-the-art technology procuring latest machines available and has already sent a doctor to England for training on laser surgery. Dr Kishor Pradhan will return in the next couple of weeks after completing his six-month training.
How does the surgery work?
Myopia (also called short-sightedness) and hyperopia (also known as hypermetropia or farsightedness) occur due to formation of the image either in front of or behind the retina. In myopia, the image of near objects is formed in the retina but that of distant objects is formed in front of the retina, while the image of near objects is formed beyond the retina in the case of hyperopia.
“We ablate (make thinner) the cornea by using laser to ensure that the image is formed in the retina,” said Head of the Corneal Department at Tilganga and the institute´s Deputy Medical Director Dr Rita Gurung. “We ablate the middle part of the cornea to reduce the distance between the cornea and the retina to correct myopia, while we ablate the sides of the cornea to elongate it for correction of hypermetropia,” Dr Gurung explained.
She added that even people with presbyopia can benefit from the surgery by the means of monovision. “One eye is corrected for distance vision, while the other is corrected for near vision in monovision surgery,” she explained.
Who can undergo laser surgery?
“We have to perform many examinations of corneal refraction, corneal thickness, eye pressure and others before a person is deemed fit for laser surgery,” Dr Gurung said. She explained that people with thin cornea cannot undergo the surgery as a thin cornea cannot withstand the eye pressure.
Similarly, persons should have stable eyesight with no change in numbers. She said the patient should not have seen a change in the power of glasses for one year to be eligible for the surgery. “There is nothing like an absolute number in medicine but refractive power becomes more or less stable in the early 20s and people beyond that age can use the surgery,” she revealed.
She said power alone is not the main factor in determining eligibility for surgery but those with defect of up to -1 or +1 are generally not advised for the surgery as they can do almost everything without the use of specs. “Most of the surgeries are for myopia as hypermetropia is not totally predictable and people can have change in power even after the surgery in the case of hypermetropia,” she reasoned. Pregnant women also cannot undergo surgery due to change in eyesight because of hormonal imbalance while those with corneal disease are also not operated.
She said around 96% of people will have perfect vision while the rest can have a defect of up to -1 or +1 after the surgery.
Cost of the surgery
The institute has not fixed the rate for the service yet. “I am told that it costs IRs 25,000-30,000 (Rs 40,000-48,000) in India,” she stated. She said the institute which uses cross-subsidy--using money charged from the well-to-do to subsidize rate for the poor--may charge around Rs 40,000 for the surgery of two eyes for paid cases. “We may not be able to provide subsidized service to the poor if we charge a lower rate for paying clients,” she reasoned.
The subsidized rate for the surgery, however, is expected to be much lower than Rs 40,000. “If a poor girl cannot get married due to her poor eyesight, we must do the surgery free of cost,” Medical Director of TIO Dr Sanduk Ruit said.
Related story
Tilganga Eye Hospital launches 'eye cancer awareness week'
