Unclouding Cataract And Presbyopia With IOL Surgery

KUALA LUMPUR (Bernama) -- Our eyes are our windows to the world. As we age, changes occur in our vision that may lead to a number of conditions such as cataracts and presbyopia.

A cataract is an opaque or cloudy area that forms within the eye lens, making vision difficult while presbyopia is the inability to adjust vision to see close up due to weakening eye muscles and loss of eye flexibility.

Both conditions, which are common issues that affect adults over 40, can be treated with cataract surgery and the implantation of intraocular lens (IOL). This surgical treatment allows the removal of the eye’s cloudy natural lens and replacing it with an IOL.

For those who have cataracts, seeing through cloudy lenses is like looking through a frosty or fogged-up window.  It can cause many disruptions to their daily lives.  

According to the Malaysian National Eye Survey II published in 2014, more than one in every four older people (26.8 per cent) suffers from cataracts which have been reported to be the leading cause of blindness.

 As for presbyopia, opthalmologists have warned that there could be a significant increase in presybyopic symptoms among the younger generation due to excessive screen time especially during the COVID-19 pandemic, leading to digital eye strain problems.

 

Consultant Ophthalmologist at International Specialist Eye Centre Dr Wong Jun Shyan shared, while it is normal to develop both eye conditions as we age, it can also be caused by eye injuries, certain diseases, or medications.

“Take for example when someone develops cataracts, some of the obvious symptoms are that they experience blurred vision, double vision problems, having difficulty seeing at night, sensitivity to light and glare, as well as changes in colour vision.

“While the cause of presbyopia can be due to loss of elasticity in the lens and reduced function of the ciliary muscle (a specific muscle inside the eyeballs which changes the shape of the lens when your eyes focus on near objects), medical conditions such as diabetes, multiple sclerosis or cardiovascular diseases, and also the consumption of certain drugs like antidepressants and antihistamines can worsen the condition,” he told Bernama recently.

With presbyopia, the lens inside our eye progressively loses its flexibility, making it harder for our eye to focus on the light reflected from objects, he added. The eyes need to focus on the light correctly as it allows the process of converting the light into electrical signals, which reach the brain to process the images we see.

“When faced with a condition such as a cataract or presbyopia, individuals may feel vulnerable and struggle with a sense of loss, which can reduce their quality of life significantly. That is why having a good support system will assist greatly in the patient’s journey to recovery, and this includes their healthcare team.

“They should seek ophthalmic attention for their visual blurring or disturbances. Ophthalmologists are an integral component for patients with vision problems and those who have decided to undergo eye surgery to reverse blindness from cataracts or reduce their dependency on glasses,” he said.

 

Meanwhile, a Consultant Ophthalmologist at Gleneagles Hospital Kuala Lumpur Dr Cheong Fook Meng said that people suffering from cataracts and presbyopia can be treated efficiently through surgery and innovative replacement IOL options.

This surgical treatment allows the removal of the eye’s cloudy natural lens (cataract) and the eye will be able to see much clearer with the IOL implanted. The IOL power is customised according to the patient’s eye shape and size and personalised according to the patient's vision needs.

“In Malaysia, there are a variety of IOLs available be it in government or private hospital settings. These include the Monofocal IOL which provides a clear single-image vision at a fixed distance and is usually customised for eyes to see distant objects. They restore vision for one area of focus only.

“In contrast, the Multifocal IOLs are designed to provide good vision for various distances such as far, intermediate, and near. In addition, the Toric IOLs improve the quality of vision by reducing pre-existing astigmatism and are recommended for patients who have astigmatism in their eyes. They are available in both monofocal and multifocal lens types,” he said.

 

There are other technologically advanced lenses available known as the Presbyopia Correcting Intraocular lens (PC-IOL), which can be implanted into the eye after cataract removal to allow the patient to see far and near without relying on spectacles after the operation.

Dr Cheong said there are two common types of PC-IOLs including the trifocal intraocular lens and the extended depth of focus (EDOF) intraocular lens.

“The trifocal IOL lens is based on diffractive optics. Precise diffractive rings are designed into the IOL. When light waves strike the diffractive elements of the IOL, some of the light is bent in a different direction. This optical property allows the IOL to focus light from far distances, intermediate (60 to 80cm), and near distances onto the retina. This provides the patient with the ability to see far, intermediate, and near without relying on spectacles.

“While the latest EDOF IOLs work by modifying the shape of the light waves that strike the transitional elements on the anterior surface of the IOL to stretch the good quality image formed for far distance vision, towards the intermediate distance range. The benefit of EDOF IOLs is that they allow the patients to extend their vision from far distance to the intermediate range without depending on spectacles. A proportion of patients may also have some functional near vision as well.

“For individuals who do not want to rely on spectacles at all, many are happy with the spectacle independence that the trifocal IOLs can provide. They may experience a bit of glare and may see haloes around car headlights and streetlights when they are out at night, but they can adapt to it in exchange for the freedom from spectacles or contact lenses in their daily lives,” Dr Cheong added.

 He also stressed on the importance for Malaysians to equip themselves with knowledge of the IOL options available when discussing lens choices. An ophthalmologist will have the expertise to help select the appropriate IOL based on the patient’s optical goals, requirements, preferences, and eye eligibility.

 

Edited by Salbiah Said

BERNAMA