NUH specialist's claims on cataract op refuted by peers

SINGAPORE - Claims that a National University Hospital (NUH) eye specialist made to the media earlier this month have resulted in a backlash from other ophthalmologists.

In lauding a newer, laser-assisted way to remove cataracts, Dr Lennard Thean made unfavourable comparisons to the ultrasonic-cutting method commonly used by most eye surgeons.

He had said that half of the 40 patients who had the newer and more expensive procedure lost a negligible amount of "endothelial cells". Loss of these cells could affect clarity of sight.

He had also said patients who undergo the traditional surgery could lose 10 per cent to 40 per cent of the cells.

This information is not true, said other eye specialists.

Private eye doctor Jerry Tan wrote to Dr Thean to say that "unless NUH doctors are very bad surgeons, 10 per cent to 40 per cent is not the norm".

The subject also came up for discussion at the annual general meeting of the College of Ophthalmologists - the society for eye doctors under the Academy of Medicine - over the weekend.

The college has since written to The Straits Times Forum page to correct the impression given by Dr Thean.

Dr Yip Chee Chew, honorary secretary of the college, said it was "inaccurate" to say that standard cataract surgery could result in up to 40 per cent cell loss. He pointed to medical studies into the normal method over the past six years, which have shown cell loss of 1 per cent to 10 per cent.

Even a procedure performed by a junior resident registers a cell loss of only 11.6 per cent.

Dr Yip added that "the current technique (for cataract surgery) has set an extremely high standard in safety, comfort, expediency and outcomes over the years".

As for the advantages of the newer procedure, the college said in its letter: "Without performing a proper study over a period of at least six months, it would be premature to draw such conclusions."

NUH has been using the new technique for less than two months.

However, the Singapore National Eye Centre (SNEC), Gleneagles and Mount Elizabeth hospitals have been using the laser machine for about a year.

In a reply to Dr Tan that was copied to the College of Ophthalmologists, Dr Wong Tien Yin, who heads the NUH ophthalmology department, defended the 40 per cent figure cited by Dr Thean.

He said: "In NUH, there are some cases with loss as high as 40 per cent." He explained that these high rates occur in patients with certain problems. These include having a "low endothelial cell count" before surgery.

A cataract occurs when the lens in the eye turns cloudy. Surgery is used to replace the lens with an artificial one. More than 30,000 cataract operations are done here each year, with half of them done at the SNEC.

Dr Ronald Yeoh, a private practitioner who performs about 500 cataract operations annually, said the new laser machine makes surgery easier and more accurate.

One in five of his patients is willing to pay $1,500 more for treatment with the new machine.

But whether its use provides a better outcome for patients who are already being treated by an experienced surgeon is difficult to say, said Dr Yeoh, who also teaches cataract surgery at the SNEC.

While it is rare, a trainee might incur a 40 per cent cell loss during surgery, he added. But experienced doctors usually keep the loss to under 10 per cent.

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