Marvels and concerns in modern eye care | Sunday Observer

Marvels and concerns in modern eye care

12 December, 2021

Technological interventions of a multidisciplinary nature have improved eye care methods for more refined, accurate and precise results.

Dr. Champa Banagala, Consultant Eye Surgeon spoke at length of the novel era of eye care including its marvels and concerns, at the 30th Susan George Pulimood oration organised by the Visakha Vidyalaya Old Girls Association, recently. The oration is held annually to honour the much-loved past principal of Visakha Vidyalaya, Susan George Pulimood.

Technology

On modern eye care, Dr. Banagala said the technological integration and medical breakthroughs in the past few decades have enriched ophthalmology and helped immensely to serve the people with different kinds of visual problems. Stem cell therapy, gene therapy and microchip and signal processing (artificial eyes) have shown rewarding results, especially for patients with low vision related problems.

Dr. Banagala said small incision surgery with shorter operative time and short hospital stay has benefited many patients worldwide. Most of these technological interventions were mainly through innovative applications in lasers, biomaterials, and ultrasound technology.

“The era of digital health and artificial intelligence (AI) in ophthalmology has already dawned. The digital era has provided new tools that improve the efficiency and availability of eye care services through digital health and telemedicine. In telemedicine, electronic transmission of health care data is forwarded to the ophthalmologist for an efficient service. Such action will particularly help those living in rural and remote areas of many countries,” Dr. Banagala said.

Artificial intelligence

Artificial intelligence-based systems can identify the difference between normal and abnormal images after eye screen within seconds, enabling ophthalmologists to act early and efficiently.

On lasers and eye care, Dr. Banagala said this has revolutionised modern-day ophthalmic surgery, be it corneal, cataract, retinal or any other related condition.

“The beauty of Fem to second laser is that it can be used for accurate cuts, without damaging surrounding tissue since energy is focused on a particular point,” she said.

Biomaterial, a substance engineered to interact with biological systems for a medical purpose - either therapeutic or diagnostic, is used therapeutically to treat, augment, repair or replace a tissue function of the body. Biomaterials are used in the manufacture of different intra ocular lenses and contact lenses, she said.

Corneal diseases

With regard to corneal diseases, Dr. Banagala said it is a leading cause of visual impairment, ranking as the fourth commonest cause of global blindness: after cataract, glaucoma (often associated with excess pressure in the eye) and age-related eye condition, and macular degeneration.

She said it is now possible to replace only damaged layers of the cornea with a donor graft, while leaving the healthy part of the cornea intact.

Amniotic membrane, taken from the placenta is considered an important medical device with many applications in regenerative medicine. When there is a severe damage to outer surface of the cornea, Amniotic membrane graft helps to clear the cornea. Amniotic membrane are now available commercially. In Sri Lanka, it is available at the Sri Lanka Eye Donation Society, she said.

Limbal stem cell transplantation has been developed for the treatment of many corneal diseases such as corneal scarring, chronic inflammation and so on to restore the damaged corneal surface. Dr. Banagala said one of the recent surgical techniques to reshape the cornea is known as Laser-assisted in situkeratomileus or in short LASIK. This is to correct the refractive error of the cornea to avoid wearing glasses.

In a condition known as Keratoconus, the cornea grows thin, becomes weak and protrude. One of the treatments is to insert crescent shape clear polymer rings known as “INTACS” to reshape the cornea. “INTACS” will make the cornea flattened and closer to its original dome shape, she added.

Corneal transplantation is another important surgical treatment for many common corneal diseases.

Cataract

Cataract surgery is commonly performed in Sri Lanka. Dr. Banagala said, in other parts of the world, the laser surgery is adopted. It is done more precisely with focused light where less energy is required to break up the cataract. However, laser-assisted surgery is not currently carried out in Sri Lanka.

Over the past decade, a variety of intraocular lenses with special designs have been produced: improved both in terms of corrective power and the quality of the vision provided.

Glaucoma

“Glaucoma can cause damage to the optic nerve reducing the field of vision. It is known as the silence killer of vision because the disease is progressed over the years with no symptoms till the late stages. By the time the patient notices visual field changes, the disease has progressed. The end stage is tunnel vision. Patients experience it as if he/she is looking through a tunnel. The danger of Glaucoma is that it is irreversible.

Therefore, it is important that all family members of a person getting treatment for eye pressure get their eyes screened regularly, Dr. Banagala said. The earliest glaucoma changes are seen in the blood supply to the optic disc in Optical Coherence Angiography or OCTA, a test done for imaging blood vessels.

When changes in the nerve fibers occur, it can be diagnosed early with Optical Coherence Tomography, she said. Glaucoma is usually treated with eyedrops: laser or surgery are the other options.

“Micro-implants are the recent advances in Glaucoma surgery. These are made of biomaterials and are known as stents. They will drain the fluid in the eyes to reduce eye-pressure.

Diabetes

Diabetic retinopathy is a complication of diabetes that affects eyes. It’s caused by damage to the blood vessels in retina.

“Diabetic patients should look out for retinopathy changes every year. If not, it will progress to hemorrhages and exduates in the retina. This may reduce vision if it occurs at the centre of the eye. When new vessels form in the retina and optic disc, it will lead to bleeding in the eye. At this stage, the patient will experience black particles moving in front of the eye. For this, laser therapy or injecting drugs called Anti- Vascular Endothelial Growth Factor therapy (anti- VEGF) to regress vessels is needed,” she said.

The end stage, known as Retinitis Proliferans, requires surgery which takes long hours and prognosis is poor.

Global myopia is expected to increase and it is estimated that over 50 percent of the world population will be myopic by 2050, especially children.

For many years, myopia was corrected with either spectacles or contact lenses. Currently, many new different treatments are available depending on the person’s condition and the age, Dr. Banagala said.

Laser surgery can be performed only when myopia becomes stable. Until then, new methods are used to prevent the progression of myopia.“There are two types of therapeutic contact lenses that control myopia progression: orthokeratology night-time lenses and multifocal day-time soft lenses. The other option is multifocal eyeglasses-myopilux lenses or executive bifocal glasses.

Recent research has revealed that diluted Atropine eye drops can be used to prevent progression of myopia in school-aged children. Currently, these drops are used in other countries. Recent research has shown that children should be exposed to sunlight to prevent myopia progression. They should be encouraged to play outdoors daily and limit using tabs, computers and mobile phones,” Dr. Banagala said.

With Presbiopia (inability to see near), several options are available such as the use of spectacles and contact lenses. Other options are Lasik, called Presby Lasik or Corneal Inlays placed inside the cornea to change the refractive power of the cornea.

Gene therapy

Gene therapy and genetic engineering are two closely related technologies that involve altering the genetic material. This is applied in an incurable genetic disease that causes blindness in men (known as Choroideremia) and transmitted by females. The disease is caused by a defect in the X chromosome. The treatment involves injecting a harmless virus carrying the Choroideremiagene directly into the retina’s light sensitive cells.

Dr. Banagala also warned of the dire consequences that the digital revolution would have on the eyes.

“The unprecedented use of the digital screen by people over the last two years, (due to the pandemic situation) has worsened this situation,” she said.

Blue light exposure-Digital Eye Strain, visual fatigue, or computer vision syndrome occurs when a person stares at a screen for a long time, whether it is a computer, TV, phone or tablet.

Blue light scatters more making it harder to focus which will reduce your visual contrast. This is why you feel eye strain, Dr. Banagala said.

Digital revolution

Although there is no evidence that blue light from computers will directly lead to an eye disease, there is concern that it might lead to problems with sleep.

The symptoms of Computer Vision Syndrome involve eye fatigue, itchy eyes, dryness, blurred vision, double vision and headaches.

She said one of the simplest remedial actions for this is to follow the 20 – 20 – 20 rule.

The rule is to relax eyes by looking beyond 20 feet, for 20 seconds after using for 20 minutes.

“In addition, the correct posture will also help to reduce the eye strain since it will lead to correct focusing. The desktop should be 45c.m. to 75 c.m. away and your eyes have to look down to the center with about 20 degree angle,” she said.

Dr. Banagala added that the global need for eye care is projected to increase dramatically and that scientific and technological advances have opened a wide range of clinical and research opportunities that have the potential to accelerate future eye care. “We hope that Sri Lankans too can reap fruits of such revolutionary developments without delay,” she added.

Comments