Glaucoma patients may soon have a hassle-free and more effective alternative to daily eye drops in managing their condition

INSTEAD OF HAVING TO USE DAILY EYE DROPS, SOMETIMES SEVERAL TIMES A DAY, GLAUCOMA PATIENTS WILL SOON HAVE A MORE CONVENIENT AND EFFECTIVE OPTION – AN IMPLANT.  This would mean patients would only need to see their eye specialist a few times a year to keep the condition under control.

“Delivering medication through eye drops is not ideal.  You’re lucky if 10 per cent of one eye drop gets to the right site.  The rest is drained out through the nose and to the back of the throat,” said Dr Tina Wong, Head, Ocular Delivery Research Group, Singapore Eye Research Institute (SERI).

In addition, eye drops for glaucoma can cause allergic reactions and daily discomfort, and because of this, many patients stop using them.  In fact, a recent study from SNEC showed that almost 90 per cent of patients in Singapore stopped using eye drops as instructed after three years.

To address this shortcoming, the SERI team in collaboration with engineers from Nanyang Technological University, has developed an implant that gradually releases the right amount of medication into the eye.  The implant currently needs to be replaced every two months.

“Patients will be given a local anaesthetic before we inject the implant into the surface of the eye,” said Dr Wong, who is also Consultant, Glaucoma Service, Singapore National Eye Centre (SNEC).

“Patients won’t be able to see the needle, and with the anaesthetic, it is less painful than regular vaccinations.”  With the gradual release of the medication, doctors can ensure that patients receive the right amount every day to stop their vision from worsening.

“The medication we are using is already approved and is currently used by ophthalmologists to treat glaucoma in eye drop form.  With the new method, we’ve bound this drug into several layers, each dissolving slowly over time,” said Dr Wong.  “These layers are already used in other treatments and devices, such as cardiac stents and for the delivery of anti-cancer drugs, and are safe for patients.”

“Because we’re using existing drugs, we have not seen any unwanted side effects in our animal studies so far,” added Dr Wong.  Immediately after injection, a small blister forms on the surface of the eye, but this is painless and disappears within 30 minutes.

The new approach will be tested for the first time towards the end of this year, on a small, selected group of patients suffering from severe glaucoma.  After that, trials involving larger groups are required to test the implant’s efficacy and whether patients can accept this form of treatment.

“While it will take a few years before this becomes readily available alternative to eye drops, suitable patients may be approached to take part in some of the larger clinical trials over the next few years,” said Dr Wong.

With the implant, the researchers hope that patients’ quality of life will be improved by preserving their remaining vision, as glaucoma is usually not diagnosed until 80 to 90 per cent of the peripheral vision is lost.  About 70 million people are affected worldwide by the condition, which is the leading cause of irreversible blindness. 

“In Singapore, more than three per cent of the population is affected by glaucoma,” said Associate Professor Aung Tin, Senior Consultant and Head, Glaucoma Service, SNEC.  “This percentage gets much higher the older you are.  Six per cent of 70-year-olds are affected, and once you hit 80, you have a one in 10 chance of becoming blind from glaucoma.”

This research project was funded by a grant from the National Research Foundation awarded to SERI to pursue research on glaucoma and corneal diseases.  The project was presented at this year’s Asia ARVO Meeting on Research in Vision and Ophthalmology.

First-of-its-kind study looks at Asian causes of eye infections

Singapore National Eye Centre (SNEC) is driving the largest study of eye infections, involving 11 centres in eight Asian countries.  Eye infections are the second most common cause of corneal blindness in Asia after cataracts. 

“In Asia, we have two main causes of eye infections.  In more developed countries such as Singapore, where many people wear contact lenses, the most common cause is contact lens infection,” said Professor Donald Tan, Medical Director, SNEC.

“In developing countries on the other hand, the most common cause is agricultural injury, where germs, grit and harmful substances make their way into the eye.”

Data from 6.000 people with eye infections will be analysed to profile the types of infections most commonly seen in Asia, what causes them and whether the most effective treatments are being used.

“Unlike in the West, where most eye infections are caused by bacteria, in Asia, we believe that fungal infections are as common, if not more common.  Yet, there is only one anti-fungal eye treatment available,” said Prof Tan.

By profiling eye infections seen in Asia, researchers hope to work with industry partners to create solutions, such as new anti-fungal medications for patients here. 

“The other benefit of this study is that we are collecting samples of the bacteria and fungi that cause infections across Asia.  These samples can then be used to test items such as contact lens solutions for efficacy,” he said.

Currently, manufacturers rely on laboratory-generated bacteria and fungi which may behave differently.

National recognition for doctor

For her efforts in improving the care of glaucoma patients, Dr Ting Wong, Head, Ocular Delivery Research Group, Singapore Eye Research Institute, and Consultant, Glaucoma Service, Singapore National Eye Centre, recently received a Clinician Scientist Award from the National Medical Research Council. 

This national award supports clinician scientists with funding and protected time to focus on their research.  Dr Wong is one of 25 recipients of the award to date.

Besides investigating new treatment options, she is also involved in improving the outcomes of surgery for a certain type of glaucoma.