Singapore surgeon treats severe eye damage using mouth tissue, donated stem cells

SINGAPORE – Imagine having a piece of sandpaper running over your eyes every time you blink – and the average person blinks around 20 times a minute.

That was the reality for Singaporean housewife Fikriyah Mohamad Nor, 30.

She suffered from Stevens-Johnson syndrome (SJS), a rare, serious disorder of the skin and mucous membranes which causes blisters in or on the eyes, mouth, nose and genitals.

In severe cases, the skin detaches and peels away, leaving raw, exposed areas.

If left unchecked, the condition often results in death, usually due to complications such as sepsis, severe fluid loss or organ failure.

SJS is usually triggered by a reaction to medication such as antibiotics, but for some patients, the cause is unknown – as in the case of Fikriyah.

The mother of five developed a fever in 2018 which turned serious quickly. She developed blisters all over her body, on the cornea and conjunctiva of her eyes, and inside her mouth.

“At the emergency department, I could not speak or move because of the blisters and the pain. I was warded for two weeks before I was sent home with pain medication and antibiotics... The blisters eventually went away, except those in my eyes,” she told The Straits Times.

She was unable to blink as doing so would cause the dried-out margins of her eyelids to scrape against the eyes. The lid margins are the thin edges of the upper and lower eyelids where the skin meets the eye.

Her eyes became extremely dry and she could not open them.

Fikriyah was later referred to the Singapore National Eye Centre (SNEC), where she was prescribed eye drops.

It was only seven years later that she was referred to senior consultant Ong Hon Shing from the centre’s Cornea and External Eye Disease Department. She found out that the delicate tissue of her inner eyelids had turned into tougher skin.

The doctor performed mucous membrane grafting on her left eye. It is a surgical procedure in which healthy mucosal tissue, usually harvested from the mouth, is transplanted to the affected eye, replacing the scarred tissue and restoring proper function.

Ong, who is also the deputy clinical director of the Singapore Eye Bank, said that when a patient is diagnosed with SJS, the priority is usually to save the life of the patient.

“If the patients survive, 90 per cent develop acute complications, while 80 per cent develop complications of chronic inflammation. The dermatologists are... referring them early to us now so that we can do early interventions in the burns unit itself,” he said, as such conditions are like second-degree burns with pain and blisters.

One of the complications of chronic inflammation is a change in the lid margin, resulting in the production of keratin, the primary building block for hair, skin and nails. “The lid margin is meant to be moist, wet and smooth, but with the keratin, it becomes like sandpaper... So, with every blink, it rubs on the cornea,” Ong said. The resulting tiny scratches cause the cornea to lose its transparency and also leads to inflammation, he added.

“For Fikriyah, we removed the keratin on the lid margin of her left eye and replaced it with lining we took from the inside of her lower lip. Basically, it is replacing the abnormal tissue on the lid margin with mucous membrane from the patient herself, which is moist, wet and smooth.

“This lining could be taken from any part of the mouth, but we took it from her lower lip,” said Ong.

The operation was carried out in February, after which Fikriyah could open her left eye.

She said: “I am looking forward to the date (of the operation) for my right eye.”

Ong, who was trained at the world-renowned Moorfields Eye Hospital in London, has been performing the procedure since 2022. To date, about 12 patients have undergone it at SNEC.

He said this procedure prevents the condition from worsening to a state where stem cells essential for restoring the cornea’s surface stop regenerating, leading to chronic pain and cloudy vision.

Replacing stem cells in cornea

For 43-year-old Indonesian Sunarya, who goes by one name, the condition was much worse than in Fikriyah’s case. The shipping agent was living and working in Batam when he developed SJS from gout medication in 2019.

He sought treatment at hospitals in both Singapore and Indonesia, but when the Covid-19 pandemic struck, he could only use eye drops prescribed by doctors, causing his condition to deteriorate.

By the time his friend suggested treatment at SNEC, Sunarya had developed total limbal stem cell deficiency, a condition where his cornea lost all of its stem cells and was unable to heal. As a result, the cornea became overgrown with opaque tissue and blood vessels, leading to functional blindness.

This meant he required surgery to transplant stem cells from a cadaveric donor’s eyes.

Ong, in preparation for the surgery, underwent super-specialty training for a month at Sankara Nethralaya Ocular Surface Disease Centre in Chennai, one of India’s largest super-specialty eye hospitals.

It is the best place to train as the institution sees many such cases due to chemical accidents, Ong said. The centre treats more than 3,500 patients and performs over 280 operations every day.

There, he learnt the simple limbal epithelial transplantation (SLET) procedure for total limbal stem cell deficiency.

“I learnt some of these techniques which are not available in Singapore... But not every patient is suitable. They need to have enough moisture in their eyes for the SLET procedure, making patient selection quite important for success,” he said.

For Sunarya, Ong restored sight in his right eye first. As the condition in his left eye is more severe, he will need not only a stem cell transplant, but also a cornea transplant.

Sunarya said that eight weeks after the operation on March 31, he was “already driving around for work”.

So far, 15 patients have undergone the surgical procedure at SNEC.

“The most remarkable thing is most patients are actually able to open their eyes after surgery. The vision comes later. Otherwise, because of the sandpaper effect, they could not open their eyes and are very sensitive to light,” Ong said.