An eye test can save your life

Modern medicine works by finding evidence to support one or more differential diagnosis at a particular point in time. Sometimes the evidence can come from seemingly unrelated parts of our body. The eye is unique in being the only organ in our body that allows a direct visualisation of its nerve and blood vessels. This offers a peephole view of the state of our health. As such, an eye test is a golden opportunity not to be missed, to gauge our overall physical wellbeing.

Starting from the eyelid and the internal content of the eyeball, all the way to the layers of its walls as well as the six muscles responsible for eye movements, all are closely connected to the rest of our body via their blood supply and innervations. One could say the eye is the “crystal ball” that can foretell our health, providing early clues that should be acted on with appropriate follow-up tests and actions, not just for sight, but also for life-preservation. Several recent examples come to my mind.

First is a very fit patient who had a persistent blurring of vision when reading in one eye and no obvious general health issues. I made a diagnosis of macula swelling secondary to blockage of a branch retina vein at the back of the eye, supported by a thorough eye examination and eye scans. Treatment with eye injections and laser was successful in restoring eyesight. Closing the case after eyesight restoration would be like missing the forest for the trees, as it is usually the underlying cardiovascular health that is the root cause of the eye disease. In fact, in a 2016 meta-analysis endorsed by the American Heart Association and American Stroke association, blockage of the retina vein was found to be associated with a 120 per cent to 450 per cent increase in the risk of stroke, depending on age.

The bigger picture

Recognising the possible bigger picture from a single problem of blurring of eyesight can indeed prompt health-seeking behaviour and ultimately save your life. In fact, my patient is contemplating a career switch from a very stressful job that is felt to be contributing to episodic blood pressure spikes, which almost certainly caused the vein occlusion in the eye.

Another is a patient with a complex intraocular lens problem who also suffered from intractable diabetes and severe diabetic eye disease. A previous cataract surgery in a neighbouring country many years ago could not stand the test of time and the inserted artificial lens implant had become wobbly, to the point of causing terrible visual distortions with every movement. After a rather “heroic” eye surgery lasting several hours, we treated both the dislocated lens implant and detached retina, but subsequent recovery of sight seemed slower than expected.

As a result of the severe diabetic eye disease, in this case, the optic nerve is no longer able to provide clues to possible brain diseases. However, due to complaints of headache and my impression that there could be more to the case, I ordered a brain magnetic resonance imaging (MRI). The result was a sizeable brain tumour that fortunately was still operable, and the final outcome of the case was thankfully a happy ending.

Many patients ask me why their eyes look “smaller” and their eye colour seems to become lighter as they age. The answer is a ring of deposit of oily (lipid) material around the cornea, which is the perceived “black of eye”. The scientific parlance is arcus senilis (pardon the language please) and may indicate a rise in the blood cholesterol level of the body, so it is highly recommended to undergo tests and treatment to manage the cholesterol level.

More than meets the eye

And if becoming senile and demented is a concern, new research also indicated that studying the retina blood vessels may give clues to early Alzheimer’s disease, although diagnosis still needs to be supplemented by neurological tests and brain imaging.

Dry eye disease can be associated with an underlying thyroid problem, and new research has also indicated an association with a lack of Vitamin D which is not rare even in sunny Singapore. I have sent many patients, some even pre-operatively before their planned cataract or laser refractive surgery for blood tests for the above, if suspicion index is high.

Sometimes these tests do turn out to be positive. Proper treatment can then improve their eye symptoms such as eye tiredness and irritation, and improve their general wellbeing too.

I always make it a point to inform young (and sometimes older) patients who sign up for Lasik surgeries which rid them of refractive errors like myopia and astigmatism, if I find any tell-tale signs suspicious of glaucoma, at the risk of sounding like nagging.

One of the associated causes for glaucoma is snoring (sleep apnoea). This may sound innocent enough, but if the end result of continuous neglect is the possibility of complete blindness, my sincere advice is to please get the snoring treated, by the ear nose and throat specialist, as believe me, blindness from glaucoma is real, irreversible and very terrible.

The English poet William Blake once wrote in his famous Auguries of Innocence: To see a world in a grain of sand, and heaven in a wild flower. So too, a quick check of the eyes can reveal more than, well, meets the eye. It may not be possible to hold infinity in the palm of the hand, but here’s wishing that we safely go through the world!

Our Eyes, Our First Defence

As Singapore emerges from the “circuit breaker”, a measured approach and long-term plan for eye care to better prepare for possible future outbreaks should be considered

SGSecure, a national campaign launched in Singapore four years ago for crisis preparedness has been a success in informing residents of the need to be vigilant against terrorist attacks and other civic emergencies. It has a catchy tagline of “Our eyes are our first defence”, with eyeball mascots keeping an eye out for signs of trouble. I cannot agree more, since our sense of sight comprises 80 per cent of our senses.

2020, the year for good vision, has quickly degenerated into the worst public health and financial crisis in a generation, no thanks to Covid-19. As the world hunkers down to avoid what seems to be a threat worse than terrorism, local essential services like healthcare, transport, food supply and infrastructure have soldiered on these two months, including my specialist eye clinic, albeit on a much smaller scale.

Eye diseases are rarely life-threatening, even though they can blind one and affect one’s independence and livelihood. Yet the trickle of patients with eye problems, significant enough to leave home to see a doctor for, has told a sobering story of how prevention is truly many times better than cure. Apart from symptoms like seeing floaters and flashes which may be due to unavoidable retina tears that can cause detachment, most other acute eye diseases are arguably avoidable, either by early detection and preventive treatment, or careful management of general health problems that may give rise to eye diseases as a complication.

Flattening the curve
Very few would have predicted that a viral pandemic could bring human activities to such an abrupt halt. Deriving Singapore’s coping strategies from our Sars-hardened political leaders, public health and infectious diseases experts, themselves on a steep learning curve, we do our best to flatten the Covid-19 curve by staying home as much as possible.

Meanwhile, life goes on, and the usual urgent and emergent health problems happen as they normally would, with some exceptions such as reduction in influenza and air pollution-related allergies. On the other hand, as a result of the stay-home campaigns, health-seeking behaviours, other than pandemic-related, are altered and delayed by the healthcare bottlenecks worldwide. As such, there are emerging signs of increased disease severity at presentation in affected specialties, with possibly higher morbidity and mortality.

Even though I fully agree with and have operated by the Ministry of Health’s guidelines on appointments and social distancing during the past crucial weeks, my heart aches when I see otherwise able-bodied patients lose their vision. Chronic diseases like cataracts can sometimes progress faster than what conservative treatment plans for. This has resulted in some patients going from doctor to doctor, seeking surgical relief for functional restoration.

Furthermore, delays in seeking medical attention can cause one’s vision to be permanently damaged from common eye diseases like glaucoma, macular degeneration and diabetic retinopathy, all of which are usually symptomless in the early to moderate stages, where commencement of treatment to preserve sight is effective and strongly advised. In the worst scenarios, patients are unaware until they reach advanced stages of these eye diseases. By then, extensive treatment is indicated, unfortunately often unsuccessful in fully restoring vision. The consequent vision loss can render one unable to adequately manage activities of daily living and to work. It is my sincere wish that the eye care profession can satisfactorily manage the backlog of cases in the coming weeks.

As Singapore emerges from the “circuit breaker” and gradually resumes life as we knew it, my personal opinion is that a measured approach and long-term plan for eye care to better prepare for possible future outbreaks be considered. Ongoing management of acute cases aside, and while safe distancing and all applicable infection control measures are followed for protection of patients and doctors, emphasis should be on eye treatment to restore function as soon as possible for affected patients, so that breadwinners and families can get on with their lives.

Further to that, monitoring of previously diagnosed chronic eye diseases, particularly unstable cases, and eye screening for patients with risk factors should not be long-delayed, so that treatment outcome can be optimised. Efficient use of downtime As food for thought, in Hong Kong and South Korea where pandemic measures are reportedly balanced and infection control generally good, ophthalmologists, particularly those in non-hospital or privately-run settings, had continued to provide “compartmentalised” services for eye care including cataract and refractive laser surgeries.

Such practices, to my knowledge, had reportedly not contributed to a spread of Covid-19, is openly accepted locally and deemed an efficient use of enforced downtime, particularly by patients seeking laser refractive correction, who are typically young adults and more resilient to the pandemic. In other countries, Covid-19 swab tests are carried out as a screening prior to surgeries. In Hong Kong, eye specialists in different sectors seem to close ranks, with counterparts in the private sector proactively contributing to the care of public sector patients.

While practices differ from place to place, I opine that a universal principle should be to improve clinic infection control and time-efficiency so that eye service quality is not compromised. While we wait for sustained stabilization of the pandemic, clinical research, particularly commercial and unrelated to the pandemic, should continue to be scaled back. Certainly, in my practice, tests and procedures that are potentially aerosol-generating such as the airpuff eye pressure test, and that are invasive or prolonged, are currently avoided in favour of those that can achieve similar aims without the downsides.

Similar to how the pandemic forces us to hasten trends at the workplace, in retail and information technology, I believe in time to come, it will shape and perpetuate practice trends in healthcare and ophthalmology too. These trends may be the adoption of telemedicine, increasing use of non-invasive and contact-less diagnostic devices and embracing newer surgical approaches to reduce risks and improve long-term post-operative results, like using laser cataract and refractive laser lenticule techniques.

One thing is for sure, Zoom and webinars have resulted in unprecedentedly large participation in both public education and professional meetings I attended in the past two months, a trend that hopefully will stay for good. As for our first defence against the pandemic in the coming weeks, in addition to face masks, may I please suggest the anti-terrorist mentality of including eye protection, particularly in crowded places, since catching the virus through our eyes is not impossible – be it a wraparound eye shield, face shield or large-framed, close-fitting spectacles, all to be washed regularly. After all, Covid-19 is the most lethal terrorist to date!

Singapore Medical Specialists Centre Breaks New Grounds In Vision Enhancement

One of the most common applications for lasers in the treatment of eye problems is in refractive correction. Due to its high safety and efficacy, laser vision correction for refractive errors has today become a mainstream approach. Providing freedom from glasses and contact lenses, it is sought after not just for convenience and cosmetic effect, but also for practical reasons, such as facilitating participation in sports, enhancing one’s career, and lifestyle pursuits. In many cases, quality of life is significantly improved following successful laser vision correction.

Compared to the first generation of laser vision correction treatments, such as the flapless Photorefractive Keratectomy (PRK) which is associated with post-op pain, longer recovery, and side effects of haze, the newer treatments, such as the flap-based Laser-assisted In Situ Keratomileusis (LASIK), are vastly more popular as they result in much shorter downtime and a higher satisfaction rate. While some patients may experience some degree of dry eyes, particularly in the treatment of higher eye power, they generally recover with proper post-operative care.

Third generation technology, such as the still-maturing Small Incision Lenticule Extraction (SMILE), a keyhole operation combining the flaplessness of PRK with the quick recovery of LASIK, can deliver even more stable results. Any small chance of eye power regression and cornea weakening (ectasia) can also now be prevented by corneal collagen cross-linking (XTRA).

Swiss Ziemer LDV™ Z8 Technology
A recent addition to the armamentarium in the refractive surgery world is the highly innovative and mobile FEMTO LDV™ Z8 Laser by Ziemer, an advanced technology that has brought a new level of accuracy, flexibility, speed, and mobility to laser eye surgeries. With its low energy (the lowest amongst all femtosecond lasers), it comes on the back of a highly respectable and continuous lineage. As an established FDA-approved femtosecond laser purpose-built for LASIK and corneal and lens surgeries, it has its roots in versions Z2, Z4, and Z6. The unique LASIK performed on the Ziemer platform is called Z-LASIK. Distinct from other makes of femtosecond lasers, the proprietary FEMTO LDV Z8 uses extremely fast, short pulses of low range pulsed light, which gives rise to a faster creation of the corneal flap (the first step of the Z-LASIK procedure) – within just 30 seconds.

The nanojoule laser allows for a gentle approach that produces an extremely smooth interface, reducing the stress on corneal tissue and post-treatment inflammation. As a result, patients can expect more rapid healing and improved vision in a shorter time frame. The laser’s small footprint and mobility also means that patients are not required to shift during different steps of the treatment, improving patient comfort and streamlining the surgical process. The flap creation is then followed by excimer laser treatment in the second step of LASIK (SMSC uses a proven NASA excimer technology, iDESIGN 2.0 VISX STAR S4, including wavefront-guided LASIK treatment).

What is interesting is that the FEMTO LDV™ Z8 does not just deliver bladeless all-laser LASIK for the treatment of refractive errors such as myopia, hyperopia, astigmatism, and presbyopia with high precision. Its adjustable 3D LASIK flap configuration is also versatile and customisable, like the Z6, with the additional advantage of an Optical Coherence Tomography (OCT) to visualise the Bowman membrane and previous LASIK interfaces, a feature of Z8 that enables finer precision work, such as LASIK retreatments or thinflap femtosecond LASIK (femtosecond sub-Bowman’s keratomileusis).

In lens surgeries, the Z8 laser delivers documented excellent results in Femtosecond-assisted Cataract Extraction Surgery. With its low energy levels, the
laser cuts are fine and precise, allowing for safe surgeries even in complex lens exchange and cataract operations. The mobility of the laser unit allows it to be positioned in the operating theatre right next to the patient, doing away with patient movement between equipment changes, creating a more comfortable experience. The Z8 is the only laser that is feasible when bilateral sequential femtosecond-laser assisted cataract surgery is opted for.

In addition to the above indications, the Z8 is able to perform femtosecond arcuate keratotomy for the treatment of astigmatism using a non-invasive method. Furthermore, Ziemer is on the cusp of releasing its Z-lenticule extraction treatment (yet to be formally named), its own version of SMILE, with added ability for centration, projected improvement in accuracy, and precision. Anticipated in the first quarter of 2020, it will be an attractive option for laser vision correction candidates seeking a flapless alternative.

Ziemer Z8 + Galilei G6
The breakthrough Z8 femtosecond laser can coordinate with the FDA-approved Galilei G6 scanner to create a complete Ziemer ecosystem. The Galilei G6, built on the G4 model, is a dual-Scheimpflug imaging/scanning device that captures up to 300,000 spots on the cornea on both its front and back surfaces and incorporates an optical biometer and Artificial Intelligence assessment technologies. It is precise for assessments for LASIK and SMILE/Zlenticule and for lens implant treatments like the Implantable contact lens (ICL), lens exchange, and cataract surgeries. The unique combination of the Galilei G6 scanner and Ziemer Z8 laser streamlines the application of pre-operative measurements, thereby improving LASIK and SMILE/Z-lenticule as well as ICL, lens exchange, and cataract surgery pre-planning, providing a clearer picture to achieve a safe and great visual outcome.

The Singapore Medical Specialists Centre is proud to be the first in Singapore to have the Ziemer Z8 combined with the Galilei G6. With OCT guidance for LASIK, we are confident we can enhance your vision with increased precision.

Vision 20/20: viewing the world perfectly

AT the dawn of a year and decade, it is fitting to review and renew our goals. 2020 holds special meaning for everyone who appreciates the sense of sight and especially for me as an eye specialist. “20/20 vision” is medical parlance for normal or optimal visual sharpness: what a healthy eye should be able to see clearly, at 20 feet. “Vision 2020: The Right to Sight” is also the name of a World Health Organization (WHO) project that was launched in 1999 as part of an ongoing project commenced 30 years ago, with the aim of eliminating avoidable blindness globally by 2020.

A global guidance and blueprint for eye care systems, Vision 2020 started with advocacy for intervention against eye diseases such as cataract, glaucoma, diabetes, Vitamin A deficiency and trachoma (parasitic river blindness prevalent in Africa) as its first priorities. To sum up Vision 2020, WHO published its comprehensive World Report on Vision last year, freely available on the Internet. Although unmet needs still exist, the project has seen unprecedented progress and is deemed successful by most yardsticks. There has been a very significant reduction in cases of eye infections and blindness from Vitamin A deficiency, as well as the ongoing reduction in prevalence of blindness among adults, including treatable causes.

Nevertheless, continuous focus is necessary as these results can’t keep pace with the growth of an ageing population. The report includes the global magnitude of the issues, successes, what remains to be done, recommended strategies and paths charted for the future. The causes of vision impairment and their impact on financial burden are of particular interest to me. The figures are staggering: at least 2.2 billion people have vision impairment globally. At least one billion of these (an underestimation according to the report) could have been prevented or are unaddressed, with 123.7 million suffering from unaddressed refractive errors.

Cataract comes in second at 65.2 million. These eye conditions are projected to increase due to population ageing, as well as environmental and lifestyle changes. From the report, the cost of the coverage gap for global unaddressed refractive errors and cataract was estimated to be US$14.3 billion. In the world, there are an estimated 2.6 billion people with myopia (of which 312 million are under 19 years old) and 1.8 billion with presbyopia. These contributed to losses in annual global productivity estimated to be US$244 billion and US$25.4 billion, respectively. The prevalence of myopia is the highest in East, South and Southeast Asia. It was reported in these regions that the economic burden of uncorrected myopia was more than double that of other regions and equivalent to one per cent of gross domestic product (GDP).

A simple calculation should convince one of the highly cost-effective outcomes for addressing treatment of myopia, presbyopia and cataract – my three main areas of practice in ophthalmology – in any health care system. There are several points in the report that strike a pertinent yet sensitive note. First, the issue of funding for management of the commonest eye condition, that is, refractive errors, which in many countries are mostly out-of pocket. These include the costs of spectacles, deemed an assistive device, as well as contact lenses and refractive surgeries such as LASIK. Second, the potential role for public-private partnerships to improve eye care services. What is new for this decade is the focus of “integrated people-centred eye care” as a continuum of health intervention.

This is a new addition to the WHO project’s action plan to now include integration of eye care into health care systems, ideally across all sectors, and, for this, four important strategies are proposed. These are to empower and engage people and communities, reorientate model of care, coordinate services within and across sectors, and create an enabling environment. In my mind, these are applicable to both policymakers and the public. Integration of eye care into health care is here to stay. For the general public, it should translate to ensuring good eye care and visual habits from the groundup, starting in the family, schools, public institutions, at work and at leisure.

It also means having eye protection in sports and in relevant occupations and attending eye screenings regularly even when the eyes feel fine, as some eye diseases are silent in the initial stages where they can be controlled and potentially reversed. Ensuring good general health and lifestyle is key in maintaining good eye health. Our eye clinic also welcomes the new decade with an addition of the services provided. Incorporating a Refractive and Cataract Surgery service  on site has long been our aim. We look forward to deliver safe, effective and integrated eye care with the addition of the trusted Johnson and Johnson Star S4 iLASIK excimer laser with FDA approved wavefront guided treatment via its latest iDesign 2.0 and the Swiss-made Ziemer Z8 femtolaser for OCT-guided thin flap LASIK surgery, being the first in Singapore, as well as for laser cataract surgery.

These will help address the most common eye conditions in the world – namely myopia, presbyopia and cataract – in an efficient and affordable manner.
The Ziemer Z8 also looks forward to providing further innovations in flapless refractive lenticule treatment for myopia in the near future. Eye screening enabled with artificial intelligence for front-of-eye diseases by dual-Scheimpflug imaging and back-of-eye diseases by digital angiography and fundal camera remains our go-to option, a sign of the times.

Dr Daphne Han
Senior Consultant Ophthalmologist
MBBS (Melbourne), MMed, MRCS, FRCS (Edinburgh), FAMS


The evolving vision of cataract surgery

Intraocular Lens Surgery: Then and Now

Many years ago, during a clinical Observership in Cataracts and Anterior Segment Reconstruction with Drs Osher and Snyder at the Cincinnati Eye Institute, one of America’s largest private eye centers, I was invited to co-author a chapter in the Textbook of Intraocular Lens Surgery (an Ophthalmology textbook eventually published in 2017 by Thieme, available on Amazon and Kindle).  As part of my research for writing this chapter, I acquired a vintage book titled “Intraocular Lenses and Implants”, widely regarded as the first ever textbook on the subject, written and hand-signed by Dr Peter Choyce.

For the uninitiated, cataracts are opacification of the lens in our eyes, arising from aging and accelerated by certain diseases, medications and trauma.  Choyce, along with his more famous mentor Sir Harold Ridley, were pioneers of the intraocular lens (IOL) for the use in cataract extractions in the 1940s.  They recognized the shortfalls of conservative management with thick spectacles and unwieldy contact lenses to “replace” the focusing power of the extracted lens after cataract surgeries.  That their inventions are by now a staple in cataract surgeries, the commonest operation in the world, belies the struggle for acceptance, complete with disdain and discourteous actions from many colleagues that they had to endure back in those early days.

Inspired by pieces of perspex from shattered warplane canopy that lodged inertly in the eyes of World War II fighter pilots which he treated as an army doctor, Ridley designed the first IOL and implanted the first case at St Thomas’ Hospital, London in 1949.  It wasn’t until significant improvements in designs were made and 20 years since, before the IOL became mainstream and recognitions streamed in for the inventors in the 1970s, culminating in the Gonin medal, the highest award in Ophthalmology for Ridley. The rest, as they say, is history.

In my eyes, Dr Choyce’s IOL designs illustrated in the musty book published in 1964 are remarkable.  Some were for lens replacement in traumatized eyes, iris replacement and routine cataract operations.  Now seeming “retro”, these ideas fathered the current generations of IOLs, and may continue to do so.  In fact, some novel creations in the current IOL market echo these first designs, such as the IC8 pinhole IOL which may have been inspired by the Choyce stenopaeic aperture IOL, and the telescopic IOL, with the difference being the IOL shape and locations within the eye had changed.

Fast forward to 2019, generations of IOL designs had come and gone, and millions implanted into human eyes, the vast majority to the recipients’ benefit. IOL materials improved, sometimes arising from mistakes in the past.  Together with advances in lens extraction techniques using ultrasound (phacoemulsification) and nowadays with a touch of femtosecond laser, modern surgical incision sizes are much smaller, and safety and efficacy approaching perfect.  In fact, IOL surgeries have evolved to become highly refractive, often bettering the pre-operative eye power.  From my experience as a cataract and refractive surgeon, this contributed to a significant shift in our mindset, even leading to refractive lens exchange without significant cataracts. It seems de rigueur for many resourceful patients to expect no less than perfect eyesight AND eye power from their IOL operations, thanks to the sophisticated IOL designs and variety, meticulous pre-operative measurement and surgical planning, which together can and often successfully meet these heightened expectations.  A version of the IOL, called the implantable collamer lens (ICL) can be implanted into eyes without lens extraction, a solely refractive operation, which I also perform as a premium alternative to laser in-situ keratomileusis surgery (LASIK).

New designs continue to pour into the IOL market almost every year. Suffice to say that currently, in general the simpler IOLs correct basic eye powers, while more advanced IOLs, which cost more, can also manage additional errors such as astigmatism, sphericity and presbyopia (e.g. multi focal and extended range lenses).  Competition amongst IOL companies produces some unique differentiating features, whose merits the companies work to substantiate, and ophthalmologists critically assess and responsibly peruse to benefit their patients’ IOL surgery visual outcome.

As a result of the plethora of IOL designs, it behoves any potential cataract surgery candidate to take a moment to understand their choices, as the surgery should ideally be done just once in a lifetime.  Apart from IOL, vision and visual quality results, technique of surgery such as with or without laser should be discussed, as these choices may affect short or long term outcome.  The final option depends on the activities and lifestyle of the individual, and other aspects of the eye and health.  While cost is a factor in the choice of implant and technique, there are alternative strategies that fall not far behind and sometimes arguably better, including glasses or the popular LASIK, for instance, for further refinement after cataract and IOL operations.  Personally, I find calculating for my patients an accurate IOL power a rewarding part of my clinic’s services.  I currently employ a ray tracing software based on a Swiss-made eye scanner, and regularly audit the results, which I find excellent and had shared at the recent congress of the Asia Pacific Academy of Ophthalmologists.

As such, with the increased IOL choices, increased “chair time” is expected, and a clear and thorough conversation should be sought between doctor and patient, since these surgeries are rarely emergencies.  For me, all individuals are unique and so are their eyes, hence a customized approach to the IOL choice is called for.  Occasionally, true suitability for some of the more complex IOL designs e.g multifocals (bi- or trifocals) can only be fully ascertained after a period of post-surgical adaptation, making clear and open communication even more important.

As for my two precious textbooks of Intraocular Lens Implants (the first and the latest published to date, to my knowledge), I may just read them side by side, for my fascination, perspective and gratitude. Indeed, we see further when standing on shoulders of giants!

Dr. Daphne Han
Senior Consultant, Ophthalmologist
Singapore Medical Specialists Centre

The Business Times, Saturday, 15 June 2019

Set your sights on eating right

Set your sights on eating right

Have you ever eaten “with your eyes”? The chances are yes.  Apart from odor and taste, the sight of food contributes significantly to our assessment and enjoyment of food.  In fact, the glamourised appearance of a particular food item often becomes the single most powerful advertisement, especially on social media, to the extent that it becomes commonly called food pornography.  As such, eating with our eyes is certainly a true fact, underlining the importance of our sense of sight in the quality of life.

But have you ever thought of eating “for your eyes”?

Eating to see well follows universal dietary principles, which are to have a varied, broad-based diet and preferably fresh food from uncontaminated sources.  In addition to this, several unique food apply to visual health.  I would divide them into two categories, broadly-speaking: eating for the health of the front of eye and the back of eye.

Firstly, the front of eye.  The ocular surface comprising the cornea and conjunctiva is what meets the environment.  The cornea, a transparent tissue, permits light through, and provides structural integrity to the front of our eyes, while the conjunctiva is the lining of the white of our eyes.  These are usually protected by a thin layer of fluid called the tear film, which can dry out when blinking rate drops due to prolonged visual attention.

Modern, desk-bound lifestyle sees many of us glued to computer screens and for way toolong. The consequence of that is an increase in what is termed “digital eye strain”, which causes tired eyes and sometimes, blurring of vision due to dryness and exposure.  Coping mechanisms are none other than reducing the duration of near work and taking frequent visual breaks.  Dietary supplements in the form of omega-three fatty acids, either fish oil or plant-based in origin, are commonly prescribed for dry eyes syndrome.  Simplified, they work in a two-pronged way: strengthening the external oily layer of the tear film to prevent early evaporation of the tear, and also to improve the health of the oil glands at the lid margin, a vital part of our eye surface.  These supplements are, in my experience, truly helpful for low to moderate grades of dry eyes, and are generally very safe to be consumed long term.  They are available over the counter in most pharmacies, with several formulae produced specifically for dry eyes, even though generic formulae are often just as effective.  .

From my understanding, the amount of these fatty acids acquired from modern day regular meals are usually insufficient, and there are no issues in taking supplements in the form of capsules for these.  I occasionally suggest oil forms of these supplements, added to salads or soups.  I routinely recommend these supplements to my cataract and LASIK patients, who usually will encounter a short duration of dry eyes post-operation.  However, severe grades of dry eyes should also be treated medically with prescription eyedrops.

Eye problems arising from nutritional deficiency such as night blindness and xerophthalmia (very severe dry eyes) from severe lack of Vitamin A are very rarely encountered nowadays due to the improved diet in our society.  There is some evidence that adequate Vitamin C from natural food sources has protective effects against cataract formation.

For the back of eye, the central area of the retina called the macula is where photoreceptors are the most concentrated and hence the most sensitive area of our retina.  The macula is the site of insult of two common eye diseases: diabetic retinopathy and age-related macula degeneration.  This area, when affected by these diseases, may swell up, bleed internally and collect deposits of waste substances.  The damage caused to sight can be grave, as central vision and reading are affected.  Other than the macula, the rest of the retina may also be affected by diabetes.

Dietary guidelines for diabetic eye disease sufferers are identical to other diabetes sufferers.  Studies have, however, shown that a tight control of blood glucose level helps to maintain vision, as the tiny blood vessels of the retina succumb easily to poor diabetes control, resulting in sprouting of new and fragile blood vessels that bleed and scar, causing retina detachment and blindness in the advanced stages.

Often, a visit to a dietitian helps to plan a diabetic diet.  A diet composed of regular meals to prevent extreme blood sugar swings is the aim, while keeping intake of calories and body weight in check is definitely a plus.  Further attention to types of carbohydrate consumed may also result in maintaining an even keel.

As for age-related macular degeneration, a disease affecting the elderly in which the macula area is affected by deposits of waste material which result in abnormal blood vessels, the link between diet and vision is much studied.  These studies showed that a regular intake of lutein and zeaxanthin (carotenoids, or pigments found in naturally colourful food), zinc and vitamin A, C and E can reduce the incidence of disease and reduce the risk of disease progression by up to 25 percent.  The dietary recommendations resulting from the oft-quoted large-scale Age-Related Eye Disease Study 2 (AREDS2) form the basis of several oral supplements for macula health, available fairly readily over the counter and in most specialist eye clinics.  For natural sources of lutein and zeaxanthin, look no further than the usual colourful fruits and vegetables, including kale, spinach, papaya, blueberries, goji berries and peppers.  These colourful foods help to maintain colourful vision.

Care in avoiding the wrong food can also bode well for our sight.  Infrequent reports of severe blindness from toxicity to the optic nerves, due to accidental ingestion of methanol are still encountered in the region, even in Singapore.  Possible ocular side effects of medications such as steroids and some oral drugs for cardiac and rheumatoid diseases should also be monitored by the eye specialist, to prevent vision impairment.

Healthy eyes and vision are some of the best gifts in life.  Why not repay our eyes the enjoyment we derive from it, by eating right for our sight?

Have a date with our Specialists at 360 Health Management Seminar on 30 Mar 2019, Saturday 10am to 2pm at SPH News Centre Auditorium. Our Specialists will be sharing various health issues that you might be facing. Register online at

Dr. Daphne Han
Senior Consultant, Ophthalmologist
Singapore Medical Specialists Centre

The Business Times, Sunday, 2 March 2019

More needs to be done to manage myopia in children

More needs to be done to manage myopia in children

More needs to be done to manage myopia in children

Recently my clinic was running very low on unit vials of low dose (0.01%) atropine eyedrops, a nightly medication that is currently commonly prescribed to moderate myopia progression in children.  I was informed by the pharmacist that there is a regional shortage as the demand seemed to be outstripping the supply of this eyedrops treatment for myopia in kids.  The popularity of this medication is hardly surprising as it has been proven effective by multiple researches in Singapore and elsewhere, with almost no known undesirable side effects.  It seems to me that the production and business side of it could see improvement, and if I were an investor I would certainly explore this.

Myopia, or short-sightedness, is a rising epidemic around the world.  Recent studies showed that a trend towards increased incidence of myopia is seen everywhere, particularly in East Asian and urban areas.  Many communities are anxious that more children are getting myopic and starting at a younger age, leading to more years of seeing myopia progressing, before the short-sightedness finally stabilizes at the end of adolescence.

One of 4 types of refractive errors, myopia is particularly cumbersome as it renders one to see blur for distance, with clear sight only for near.  The higher the degree of myopia, the shorter the range of view becomes, thus affecting activities requiring clear vision outside this range, unless it is treated.  Treatment is two-pronged: optically, to provide temporary relief by glasses or contact lenses, or if a more permanent solution is required, surgeries such as laser vision correction or lens implantation can be sought, when the degree is deemed stable.  In addition, increasing focus is placed on strategies to curtail the progression of myopia in childhood, in order to keep myopia within manageable levels. Some of these include encouraging healthy visual habits such as having regular breaks during near visual tasks and spending more time outdoors.

In Singapore, huge efforts had been made both in terms of public health and education measures and in research, aiming to manage this scourge.  The efforts seem to have paid off somewhat.  Last year, we gave ourselves a pat on the back for seeing some signs of stabilization of myopia rates.  Even so, no time should be lost in rejoicing.  For many families with school-going children, regular trips to the optician’s and eye doctors’ continue in a bid to dethrone ourselves as the most myopic country in the world.  To persevere with low dose atropine eyedrops therapy for children with myopia is the least we can do to control the situation, as inevitably, more and more time is spent on near work, no thanks to the increasingly wider applications on hand-held personal digital devices.  Eyedrops treatment is as non-invasive as it gets, and higher concentrations sometimes being trialled for more resistant progressions, with increasing side effects as the medication becomes more powerful.  Next up in the regime is contact lenses, including rigid nightwear lenses (orthokeratology), which require much more handling and strict care in hygiene, without which blinding complications may arise.

Historically, myopia is not a “new disease”.  In fact, it had long existed in the Chinese, Singapore’s predominant ethnic group.  As far back as during the ancient dynasties in China, scholars spent countless hours in tiny, dimly-lit study booths preparing for the imperial exams and were well known to be myopic.  The soft focus rendered by their myopia apparently inspired many a funny and witty Tang poem, mirthfully enjoyed and passed down the generations, along with some myopia genes.  This was the topic of a tongue-in-cheek poster I had put up for the 11th International Myopia Conference (IMC) in Singapore in 2006.  The biennial IMC, currently almost in its 17th iteration, usually never disappoints me with its interesting research from the ground-up and lack of dogma.

Indeed, all the refractive errors, myopia is the only one that has been shown in studies to be associated with psychometric intelligence, particularly of the verbal kind. Interestingly, a previous study apparently found that of a group of subjects with high IQ, a large proportion had very early onset myopia compared with a control group with normal IQ.  To strengthen theories or prove alternative hypotheses, the scientific community often likes to retest similar subjects.  Of course, the devil is in the details. In January this year, a scientific study (which made for an entertaining read to me) was published in the highly respectable journal Nature, titled “Refractive Error is Associated with Intracranial Volume”.  The Japanese researchers went to great length studying the various volumes of the brain in more than a thousand young adults and concluded that myopia is associated with the total intracranial volume, but not the actual grey or white matter volume.  As an analogy, rather like how if you are an L-size for shirts you are most probably L-size for pants too.  Hence if your whole brain size is large your eyeballs would probably be large (and myopic) too, regardless of why and how the brain got to its size. Conventional wisdom would have it that both nature and nurture likely contributed to these facts and findings.

Before we rejoice in the above seemingly positive connotations of myopia, let it be known that definition of an error, in this case in refraction, still equals a state of imperfection to be improved on.  Indeed myopia should be carefully minded.  Not only does it make life inconvenient and certain activities difficult, if not downright dangerous without optical aids such as spectacles and contact lenses, it can be associated with and lead to a higher prevalence of other eye diseases.  Some of these may be blinding, such as glaucoma and retinal detachment.

While the other errors of refraction like astigmatism, hyperopia (or long-sightedness) and presbyopia (or “old-sightedness”) are equally inconvenient, none of them is as common and impactful in the formative years of a person’s life.  For instance, it may be unwieldy in certain sporting pursuits, predispose to higher incidence of injuries or mishaps, and may generally affect self-esteem or self-perception.  In fact, scientific research had shown associations between myopia and personality traits of lower extroversion and behavioural patterns such as having a narrow focus of visual attention.  In the more severe cases, hallucinations and paranoid tendencies had been reported to be linked to myopia.

Therein should be the impetus to reduce the incidence and severity of the plague of myopia, one of the most common causes of visual impairment in the world.  In my humble opinion, simply prescribing glasses for school children is not sufficient in today’s scenario, when multiple researches have shown proven benefit of medical therapy such as using low dose atropine eyedrops in retarding myopia progression. Regular monitoring with a view to such safe and effective treatment should be highly recommended in young children and teenagers.  Encouragement for more time spent outdoors in natural outdoor lighting, with the natural fluctuations in intensity that come with it, is also highly recommended, as this is what the results of several comparative studies seem to point to.

Dr. Daphne Han
Senior Consultant, Ophthalmologist
Singapore Medical Specialists Centre

The Business Times, Sunday, 11 November 2018