All-in-one cataract surgery

WITH today’s lenses, patients undergoing cataract operations can have other eye conditions “fixed” at the same time For almost three years, Mr Roger Kang, a real estate agent, lived with worsening eyesight due to cataracts.

But despite his blurred vision, he carried on with his daily activities and did not see the need for an operation.

“Although it was uncomfortable – like seeing smoke in front of you all the time – I could live with it,” he said.

Finally, having no other choice, he underwent surgery last year and was pleasantly surprised to learn that not only could he have his cataracts removed, he could also correct his astigmatism, longsightedness (hyperopia) and near vision (presbyopia) in one fell swoop.

No need for spectacles Mr Kang had premium multifocal lenses inserted into his eyes, one at a time, two weeks apart.

After the procedure, he was able to do away with his multifocal spectacles, which he had worn for 10 years.

“My eyesight is almost perfect now.The best part is that I don’t need to wear specs anymore,” he said.

He does, however, see halos around lights at night, but is not bothered by it.

“I’ve no regrets and have recommended it to quite a few friends,” he said.

Mr Kang is among a growing number of cataract patients at environment,” he said.

To try to unravel the complexity of all this, researchers at an NIH diabetes and obesity lab in Phoenix have begun to incorporate thin people into their studies.

Why “some (people) tend to overeat more than they need more consistently and why this occurs is clearly complex and involves levels of behavior that we are just beginning to understand,” said Jonathan Krakoff, an endocrinologist at the lab.

Krakoff and his colleagues are recruiting for a study in which thin people will consume about 4,000 calories in a 24-hour period, about twice the amount an average healthy person needs in a day.

Before participants engage in the overeat2ing part of the study, researchers will measure their body fat and will conduct a test to make sure they don’t have diabetes or impaired glucose tolerance.

Then, scientists will count how many calories the participants burn in a day while they’re studied.

This measurement is done in a respiratory chamber where the amount of oxygen taken in and carbon dioxide expelled is monitored, revealing the number of calories burned.

“Some people might be able to burn off more excess calories as heat when they overeat, so they are the people more likely to be thin,” said Marie Thearle, a staff clinician involved in the study.

“We are also asking our volunteers to come back for follow-up visits once a year for up to seven years to see if any of the energy expenditure measurements with overeating during the baseline study visit predict who gains weight over time and who does not.”

Thearle says the researchers hope to find out whether food choices matter.

“Once you have met the needs of your body, does it matter what else you consume?” she said.

“There’s the popular myth that people don’t gain weight because they have a high metabolism; we want to see if that is true.

We will be looking at hormones and brown fat.

We don’t think the Singapore National Eye Centre (SNEC) who have opted for premium intraocular lens implants.

In cataract surgery, the cloudy film that blurs vision is removed and a lens implanted.

Those who needed spectacles previously may be able to give them up after getting the lenses.

Lenses that multitask In recent years, cataract operations have become not just about removing cataracts.

Premium lenses allow other conditions such as Mr Kang’s, as well as myopia (shortsightedness), to be fixed at the same time during these operations.

Premium lenses are the result of the convergence of both cataract and refractive surgery technologies.

This worldwide trend has made these procedures more convenient, and provides opportunities for patients to improve their vision and become spectacle-free.

According to Associate Professor Chee Soon Phaik, Senior Consultant Ophthalmologist, SNEC, 11 per cent of the 10,500 cataract procedures performed each year at SNEC involve the use of premium intraocular lens implants.

About 50 to 70 per cent of her patients– from young professionals to older housewives – opt for premium lenses.

“Premium lenses enable a surgeon to offer patients the option of not just targeting good distance vision, but also correcting astigmatism to give very sharp vision,” said Assoc Prof Chee.

What the lenses do “In addition, they can correct visual aberrations, sharpening the vision further when the pupils dilate at night.”

Some boutique, premium intraocular lenses can also enhance vision, but need to be customised to the individual and may not be suitable for all.

But concurrent eye conditions may limit the achievable visual success.

Surgeons can guide and advise what lens would be most suitable for patients’ eyes, and address their needs and desires regarding visual performance.

Assoc Prof Chee said standard monofocal lenses in cataract surgery target clear distance vision and can correct myopia or hyperopia.

Monofocal lenses target the master eye to see distance well and the fellow eye for intermediate or near vision.

When both eyes are used together, it increases the range of vision so the patient is not that dependent on spectacles.

But patients often have residual astigmatism and presbyopia, and typically have to use spectacles for near vision.

To implant premium lenses, surgeons use the phacoemulsification technique, where a small incision of 1.8mm is made in the eye, through which the cataract is removed and the lens put in.

The incision allows surgeons to better control post-operation astigmatism and centre the lens more precisely, enhancing its performance.

Using ultrasound energy, they use the phaco needle to break down the nucleus into smaller fragments.

These become emulsified and are sucked out of the eye through the incision.

Lens materials have also improved, resulting in lenses that can now be scrolled up and slid through very small incisions, before opening to full size in the eyes.

This ability to remove cataracts through increasingly small incisions has made cataract surgery safer for patients.

Not for everyone Assoc Prof Chee cautioned that not everyone will benefit from these premium lenses and that total spectacle independence will not be possible for some patients, as the outcome depends on individual eye conditions.

For instance, monofocal and toric intraocular lenses can be used for any eye condition, including those with astigmatism.

However, implants with multifocal components are reserved for eyes which are perfectly healthy except for cataracts.

“The decision is based on the patient’s eye condition, visual needs, lifestyle and cost,” said Assoc Prof Chee.

Premium lenses are also generally priced higher, depending on the type of lens.

The cost of cataract operations can be claimed from Medisave and, depending on the particular policy one subscribes to, health insurance may cover this procedure for any type of lens.

 • This story was first published in Singapore Health, May/June 2012.