Eye Blog

date: 28/07/2018
category: macular degeneration
tags: nutrition,
macular degeneration, AREDS

One question I am often asked by patients with macular degeneration is ‘Does a healthy diet reduce or reverse sight loss?’ The answer to the question is both simple and complicated. The simple answer is a universally known and often ignored truth. ‘Yes, a healthy, well balanced diet, is always a good idea.’ The longer and more complicated answer plunges us into the great debate around the effectiveness of ‘AREDS’ formulations (a specific combination of anti-oxidants and minerals in a single pill) and the proposed benefits of the Mediterranean-style diet.

Macular degeneration affects approximately 600,000 people in the UK. It is caused by ageing or 'wear and tear' of the retina and can cause permanent sight loss. There is no known cure.

The risk of age-related macular degeneration can be cut by more than one-third by eating a Mediterranean-style diet that is rich in fruit, vegetables, legumes, whole grains, fish, and lean meats. For people who eat the equivalent of one apple each day there is a 15% decrease in the risk for age-related macular degeneration; for those who eat the equivalent of two apples each day, there is a 20% decrease. A diet rich in food with a high glycemic index (GI) increases the risk for macular degeneration. High GI foods (GI > 70) such as white rice, white bread and potatoes should be avoided whereas whole grains, lentils, and non-starchy vegetables such as broccoli are beneficial. Lastly, eating oily fish at least once a week is associated with a reduced risk of developing wet macular degeneration.

The AREDS formulation of antioxidants and minerals reduced the risk of patients with certain types of macular degeneration from progressing to severe disease by 25% over 5 years. The doses of the individual antioxidants and minerals in the AREDS formulation are higher than would be found in a normal healthy diet hence the need for ‘supplementation’. It is also useful to note that the AREDS formulation does not replace the need to eat a balanced healthy diet and that it provides no benefit to the general population for prevention of macular degeneration. It should only be taken if prescribed by an eye doctor specialising in the treatment of macular degeneration.
Last week I had two interesting and very different encounters with patients which once more raised the dilemma of performing cataract surgery in persons suffering from dementia. This can be fraught with a myriad of issues such as obtaining informed consent for surgery, deciding on whether to put the patient to sleep or not, assessing whether there is any clinical benefit to the procedure, organising post-operative care and managing expectations in a patient with impaired mental capacity. As doctors we are taught to 'do no harm' and to always put the 'best interests of the patient' first.

Families are often at a loss, wanting the best, but not always able to grasp the complexity of the process. The first encounter was with a sweet and endearing gentleman with mild dementia who was well supported by both his family and a team of competent carers. He happily placed his faith in my ability as an experienced cataract surgeon and was thrilled with the results when he attended his post-operative visit. He presented me with a bouquet of flowers and expressed his heart-felt thanks. It reminded me of why I love doing my job.

The second encounter involved a patient that I had treated for nearly two years for macular degeneration. She had always been a force to reckon with but in recent times appeared to be developing signs of early dementia. I agreed to perform cataract surgery with the help of sedation and this proceeded without event. However, after her operation she grew very agitated and abusive despite reassurances that her surgery had gone well. It was quite distressing for all.

Which brings me back to the question, is cataract surgery in dementia patients a help or a hindrance? My own experience is that patients with mild dementia, controlled on treatment, do very well with cataract surgery. It improves the quality of their life and is worth the initial challenges it may present. In severe dementia, where the patient has withdrawn from external stimulus, cataract surgery is best avoided. In untreated/ undiagnosed dementia, if the patient is unpredictable and emotionally labile, I strongly believe that cataract surgery should be delayed until a full assessment of mental health has been carried out and appropriate treatment initiated.

For further information please go to the RNIB or Macular Society websites by clicking the links below.
category: cataract surgery
tags: cataract surgery, diabetes, macular degeneration

Cataracts are the commonest cause of vision loss in people over the age of forty. They are caused by ageing of the natural lens of the eye which then loses its transparency and becomes cloudy. For most people the treatment consists of a 15-20 minute surgical procedure to remove the cloudy lens and replace it with a clear artificial implant.

However, if you suffer from diabetes you face a 60% greater risk of the developing cataracts and you are more prone to developing infections, inflammation and worsening of retinopathy after cataract surgery. The success of your cataract operation will depend on careful assessment of the main cause of your blurred vision. A pre-operative OCT scan is always carried out to detect swelling of the retina (macular oedema). If diabetic macular oedema is diagnosed, it must be treated before the cataract surgery is attempted. Further treatment is given at the time of cataract surgery and continued several months after.

If you have macular degeneration, cataract surgery carries a guarded prognosis, which means that the extent to which the sight can be restored cannot be guaranteed. Despite this, with magnifying lens implants, the timely use of intraocular injections and realistic expectations, you can experience unprecedented visual results following cataract surgery. You must understand that underlying macular degeneration can limit your sight despite successful cataract surgery and that there are options to maximise the result.

The Scharioth intraocular lens implant is a pioneering magnifying lens implant that is designed to improve vision in eyes with poor vision due to macular degeneration or diabetes.
Date: 29/10/2016
Category: NHS, Eye Appointments
Tags: Delays, Sight, Eye Clinic

Don't we Brits just love talking about the weather and the current state of the NHS? Not that we can be blamed, both are predictable only in their unpredictability.
But as the long, dark winter evenings draw in, and we put the clock backs in an effort to 'cheat' our brains into believing otherwise, our attention is diverted to the shortage of eye clinic appointments in our beloved NHS service. The reports published by the Royal College of Ophthalmologists and the RNIB of permanent sight loss occurring as a result of delays to hospital care are disturbing.

Closer to home, a recent clinical audit carried out in my NHS diabetic eye service showed that one in twenty patients suffer avoidable clinical harm if there are long delays in care. On a more positive note, I have been actively involved in developing patient pathways for those of you with less severe diabetic eye disease, so you can be seen in community eye clinics. The key to success will lie with maintaining strong links between the hospital and community services.

So how can you help take the pressure off your NHS hospital service?

Educating yourself about your condition, being healthy and complying with your doctors advice will delay the onset of diabetic eye disease which is a late complication of diabetes. Attending diabetic eye screening tests once a year helps pick up eye disease in the early stage and regular visits to your optician act as a second safety net. Lastly, being pro-active regarding your eye clinic appointments and your eye care does help. Let us know when you can't attend your appointment, or when your appointment is delayed.
Date: 29/10/2016
Category: Nutritional Supplements
Tags: Lutein, Omega 3, Macular Degeneration

I was recently asked to comment on the feasibility of keeping nutritional supplements for macular degeneration drug on the NHS formulary. Its removal would mean that it would no longer be available on prescription. I was told that there was no clear evidence of its usefulness and it would save the NHS money.

This is how I responded:
'The drug Preservision Lutein is clearly supported by evidence from the AREDS trial which is considered to be landmark trial of its kind. It enrolled 4757participants and the key finding was that in patients with a high risk of developing advanced macular degeneration there was a 25% reduction in moderate vision loss over a 5 year period.

Wet macular degeneration is the commonest cause of blindness in the elderly population of the UK and the disease has a significant public health and socio-economic impact. The annual cost of the AREDS drug per patient is £180, the annual cost of treating wet macular degeneration with anti-VEGF therapy is significantly higher (approx £4000 in drug costs alone for treating one eye of a patient for one year). A healthy diet while advisable cannot provide the recommended levels of vitamins and anti-oxidants.'

In lay terms, the use of Preservision Lutein or any other AREDS drug, will reduce your risk of developing wet macular degeneration if you have certain high risk clinical features. These features are best assessed by a retinal specialist. Recent reports from the AREDS 2 study confirm that the protective effect lasts for up to 10 years.

For further information look up https://www.nei.nih.gov/areds2/ This leaves us with one final question: What is the role of omega 3 fatty acids in the management of wet macular degeneration?
The AREDS 2 study found no additional benefit to adding omega 3 fatty acids to the formulation.

It is common practice to prescribe prophylactic antibiotic eyedrops following an injection into the eyeball (intravitreal injection). The purpose of prophylactic antibiotic treatment is to 'prevent' infections from occurring. Although rare (less than 1 in 1000 injections), infections of the eye following intravitreal injections or endophthalmitis , can be severe and sight threatening.

There are at least two good reasons not to prescribe antibiotic eyedrops following an intravitreal injection: Firstly, there is no clear evidence to show that it does actually reduce the risk of infection. Several large studies have found no difference in the endophthalmitis rates between groups of patients receiving antibiotic eyedrops after an intravitreal injection versus those who did not. Secondly, it is a well known fact that the indiscriminate use of antibiotics leads to antibiotic resistance, making infections more difficult to treat when they do occur.
(Go to www.antibioticguardian.com for further information and to make a pledge).

A recent survey of over 150 patients receiving intravitreal injections in my service at Whipps Cross University Hospital revealed that 86% believed post-injection antibiotics reduce the risk of infection. This reflects the information provided by our doctors to the patients during the consenting process and is based on the guidelines published by the Royal College of Ophthalmologists in 2009.

Surely the time for change has come...
2015 is shaping up to be an exciting year for those of you who suffer from diabetic macular oedema (swelling or leakage at the back of the eye). This is a condition that can cause sight loss if left untreated. In the past the main treatment option was laser to the retina. In 2013 this was superseded by an anti-VEGF treatment known as Lucentis, better known as a treatment for wet macular degeneration. Iluvien, another option for treating the more chronic forms of diabetic macular oedema, became available in early 2014. I was fortunate enough to be the first eye surgeon to use this treatment in an NHS setting.

This coming year will see two more drugs being appraised by the National Institute for Health and Care Excellence for the treatment of diabetic macular oedema: Eylea (aflibercept) and Ozurdex (dexamethasone). Incidentally, both already have the European Marketing Authorisation for use in diabetic macular oedema ie: available for non-NHS use in the UK.

All the new therapies are administered by a course of injections into the eye. The frequency and number of injections vary with the drug and the patient response to treatment. The challenge for the treating physician will be to formulate a clear and customised plan for each patient.
In an earlier blog I promised we would see new changes in 2015 in how we manage diabetic eye problems, specifically macular oedema. NICE (National Institute for Health and Clinical Excellence) have now approved two more injection therapies for diabetic macular oedema (DMO) so we now have a choice of four drugs: ranibizumab (Lucentis) and Iluvien and the 'new kids on the block' aflibercept (Eylea) and dexamethasone (Ozurdex) implant.

Believe it or not, approving the drug was the easy bit. Knowing which drug to use is where the clinical expertise lies. Of course there will be published guidance from the usual professional bodies and heavy weights but having written our local departmental guidance one thing is clear to me: there will be no simple algorithm to follow.

The decision behind choosing the appropriate treatment, while underpinned by the specific pharmacological qualities of each drug, will depend on each individual patients' needs and should be arrived at through a process of informed discussion. Both Ozurdex and Iluvien are long-acting steroid implants and require fewer treatments, however both can cause the eye pressure to increase leading to a condition called glaucoma.

In the NHS setting, their use is allowed only if other treatments have failed and in eyes that have had cataracts removed. Lucentis and Eylea do not have any long-term effect on eye pressure but do require frequent monthly treatment and monitoring in the initial phases with an average of 8 injections administered in the first year alone.

All these factors must be taken into account while planning the best treatment regime for DMO.