When housewife Zhang Lai Lian arrived in Singapore last October, her left eye was "melting".
Having lost her right eye in an acid attack in 2007, the 54-year- old was fighting to preserve vision in her remaining eye.
"My whole eye was infected and rotting away," she said in Mandarin. "I couldn't see anything, except detect light and darkness."
Hers was a long-drawn ordeal that stretched back to an attempted robbery outside her home in Johor Baru.
The culprit, a man who remains at large, had splashed acid on her face, and the burns were so severe that her right eye shrivelled up.
Her left eye, however, was saved after a series of medical procedures over the next few years.
It included a stem cell transplant and cataract surgery, and culminated in March 2010 with a partial- thickness cornea transplant in which part of her scarred cornea was replaced with donor tissue.
She could see again but, by 2013, scarring and calcium deposits had formed over the cornea.
Her vision was again restored after surgeons in Malaysia carried out a whole cornea transplant last year. "At first, my vision was very clear but, after a while, it started to become hazy," said Madam Zhang, who has two grown-up children - a son and a daughter - with her 54-year-old businessman husband.
An infection had crept into the eye, and it was a serious one.
About the procedure
People blinded by severe cornea diseases and whose cornea transplants have failed may benefit from an artificial cornea transplant.
One such procedure is the Boston keratoprosthesis, in which a small, button-shaped device is stitched onto the patient's eye. This device comprises a front plate with a central optical stem, which is a clear window that allows the patient to see through; a back plate and a titanium locking ring.
There is also a ring of donor cornea tissue to allow the device to be stitched onto the eye.
For complex cornea diseases in which conventional cornea transplants are prone to fail, this procedure may give the patient better long-term vision. As it is an artificial cornea, the patient does not face the problem of graft rejection, and does not need to take medication that suppresses the immune system after the operation.
An overseas study of 141 cases from 17 centres found the retention rate of the device to be 95 per cent when the patients were followed up at an average of 8.5 months later.
The Multicentre Boston Type 1 Keratoprosthesis Study, which was released in 2006, also reported that about 60 per cent of patients had at least 6/60 vision while 20 per cent achieved 6/12 vision - which is half as good as the vision of a normal person.
After the operation, the patient usually has to apply daily eyedrops, such as those with antibiotic and anti-inflammatory properties, for life.
SOURCES: OPHTHALMOLOGY, THE JOURNAL OF THE AMERICAN ACADEMY OF OPHTHALMOLOGY; AND DR LEONARD ANG, MEDICAL DIRECTOR OF LANG EYE CENTRE.
Things started to go downhill quickly. Doctors in Malaysia performed an emergency procedure to clean out the pus and infected tissue, and gave her antibiotic and antifungal eye injections.
Despite that, the infection refused to go away. By September last year, her cornea was disintegrating.
Yet another whole cornea transplant was performed but, in a matter of days, the graft melted again.
One day, the doctor simply told Madam Zhang that her entire eye had to be removed, lest the infection spread to her brain.
"I had been fighting the infection for quite a while and, suddenly, the doctor said the eye had to be 'dug out'," she said. "I was so shocked."
In a last-ditch attempt, she made a trip across the Causeway last year to seek treatment.
Her elderly mother, who is in her 70s, was her source of motivation.
"My mother has been taking care of me since 2007. She would cry when she went out to buy groceries. At home, she would lie in bed and cry for me," she said. "How could I lose my eye? I got so upset whenever I thought about this."
Accompanied by two family members, Madam Zhang first sought treatment at a public hospital here, where doctors performed an emergency cornea transplant and put her on intensive medication.
But history repeated itself. The infection returned once more, causing the cornea to disintegrate.
She refused to give up and consulted eye surgeon Leonard Ang at Mount Elizabeth Novena Hospital, who treats complex blinding eye conditions.
"When she came to see me, her condition was very critical," said Dr Ang, medical director of Lang Eye Centre. "Her cornea was so thin that it was about to perforate. If that happened, the infection would spread into her entire eye and brain, threatening her life."
Madam Zhang was wheeled into the operating theatre that very day and Dr Ang removed the infected cornea and tissue.
She received a new cornea transplant - her fifth - and was put on a wider range of medications.
However, her vision grew hazy again, as the graft was rejected by the body. There was a silver lining, though - her infection finally subsided about six weeks later.
As a sixth cornea transplant would most certainly have failed within months, she was offered an artificial cornea transplant.
The relatively new technique, known as Boston keratoprosthesis, involves stitching a button- shaped device onto the patient's eye. This implant includes a central optical stem - a clear window that allows the patient to see.
Dr Ang has performed about 30 such transplants in Singapore since 2007. About 95 per cent who were initially blind had improved vision after the procedure, he said.
Madam Zhang decided to take the leap of faith. "Even if I could see only a little, at least I could be independent at home," she said stoically.
In March, the three-hour operation was performed successfully.
So far, she has regained about 30 per cent to 40 per cent of vision and is recovering well, said Dr Ang.
Today, Madam Zhang is able to cook, do chores and even read, albeit with a magnifying glass.
To keep her eye healthy, she applies four types of eyedrops daily.
When Mind & Body met her in Singapore earlier this month, the slim, long-haired woman was even sending messages on her mobile phone. It was a far cry from a year ago, when she was entirely dependent on others to help her get around.
Her medical bills, starting from her treatment in Malaysia last year, have totalled more than $80,000.
The amount was paid with insurance payouts, her savings and loans from family and friends; but the money spent was worth it, she said. "I endured seven months of darkness. To be able to see again, I am grateful."