Thursday 28 February 2019

Healthy Eyes AMD Supplement

Dry macula degeneration has 2 subtypes, drusen based and atrophy based. In drusenoid macula degeneration there is a gradual build up of waste products in the retina, formed during the process of seeing. Just underneath the photo-receptors is the retinal pigment epithelium, the drusen deposits here disrupt the normal regular spacing of the photo-receptors and distort our central vision.

There is a gene therapy research trial being undertaken in Oxford on dry AMD, which although is in the early stages is proving promising. The degenerating process and build up of waste product is normally slow and currently the only proven way to attempt to slow down progression is to take an antioxidant vitamin/mineral supplement, such as Healthy Eyes.

Healthy Eyes are a chewable supplement containing Lutein and Zeaxanthin which is perfect for those suffering or wishing to lessen their chances of developing age related Macula degeneration.

The chews are formed from natural fruit pectin ( a gelling agent extracted from citrus fruits), giving it a pleasant and fruity taste. There are no artificial colourings or flavourings and are gelatin and gluten free. To suit most modern diets, they also contain no milk, wheat, eggs or nuts and have no artificial sweeteners.

These waste products building up in the retina are now being picked up earlier than before, with OCT scanning and Autofluorescence Photography. Matheson Optometrists are working with retinal camera developers in building a system for this. When Lipofusin (considered an aging or 'wear-and-tear' pigment) in the retina is illuminated with a specific wavelength of visible light, it fluoresces, or glows.

Wednesday 20 February 2019

Surgeons perform first gene therapy procedure aimed at stopping AMD-related blindness

The first gene therapy procedure, aimed at stopping age-related macula degeneration (AMD) has just been completed by researchers.

Robert MacLaren FRCOphth a professor of ophthalmology at the University of Oxford undertook the operation at the John Radcliffe Hospital, also in Oxford.

Professor MacLaren ran the first gene therapy clinical trials from Oxford for rarer causes of blindness, Choroideremia and retinitis pigmentosa. Professor MacLaren ran the first gene therapy clinical trials from Oxford for rarer causes of blindness, Choroideremia and retinitis pigmentosa.

The patient, Janet Osborne an 80-year-old woman from Oxford, has geographic atrophy (GA) which is associated with progressed dry AMD. It causes blurring in the central part of vision, for Janet in her left eye.

The procedure involves detaching the retina, injecting a virus-containing solution, beneath. Contained in the virus is the modified DNA sequence which infects the retinal pigment epithelium cells and corrects the genetic defect which causes AMD, reports Oxford University Hospital.

"We're harnessing the power of the virus, a naturally occurring organism, to deliver the DNA into the patient's cells. When the virus opens up inside the retinal cell it releases the DNA of the gene we have cloned, and the cell starts making a protein that we think can modify the disease, correcting the imbalance of the inflammation caused by the complement system." MacLaren stated at the release.

"It is an interesting application and approach to this very common cause of vision loss," Allen C. Ho, MD, the Director of the Retina Research Program at Wills Eye Hospital and OSN Retina/Vitreous Board Member noted.

The operation was the first phase of the 1/2 FOCUS trial, which is accessing the biological activity of the treatment, developed by Gyroscope Therapeutics.

"What's unique about this particular clinical trial is that they are trying gene therapy surgically delivered to the subretinal space to try to modify the disease process," Ho said. While other clinical trials are testing injection therapies to treat dry AMD and geographic atrophy, there are no proven treatments currently.

Ho added, "Using gene therapy for this form of the disease to modify disease progression is interesting and exciting science, but not proven yet."

UK biotech Gyroscope Therapeutics could have a mass market product on its hands if its new gene therapy for one of the most common form of blindness proves effective.

It is estimated that 196 million people globally will have the disease in 2020, while 11m will suffer significant vision loss. The company dosed the first patient with their one-off targeted injection, in hopes to prevent any further photoreceptor degeneration in the retina. In the UK already 600,000 people are affected by AMD.

Targeting the naturally occurring molecule which is responsible for activating MAC, a cell-killing factor named the membrane attack complex which in dry AMD seems to have gone rogue. MAC damages healthy retinal cells as well as unhealthy cells. The injection acts to block the molecule from attacking, this injection being the first of the companies' therapies to progress into clinic.

The initial trial will check the safety of the procedure and provide evidence that it can slow down degeneration. If early signs are positive, the therapy testing will be expanded to include patients with less advanced AMD. 

" A genetically defined treatment administered early on to preserve vision in patients who would otherwise lose their sight would be a tremendous breakthrough and certainly something I hope to see int he near future," said MacLaren. 

These pioneering advances in medicine follow on from the clinical trials for the treatment of choroideramia which has recently been successful.

Gene therapy treatments could prove useful for other conditions

Currently under trial are

Professor MacLaren said: 'This is a rapidly evolving field. Given that we understand a lot more now about the manufacture of the treatment, and the effects of the virus when doing gene therapy at the back of the eye, as well as all the other gene therapy programmes being developed at the moment, I would hope that we’ll see a treatment for people with dry AMD within the next few years.'

For further reading please see

Wednesday 13 February 2019

Recall of Intraocular Lenses

Patients have experienced deterioration in vision relating to a batch of lens implants.

Recent press has highlighted a batch of lenses used during cataract surgery, to be causing a decrease in vision. Typically the change is noticed at 36 months, where postoperative opacification has compromised the optical quality of the lens.

Photo taken under Infra Red light. You can see the plastic implant of the lens, sitting just behind the iris. The coloured part of the eye. The lens is clear when it is first implanted, here there is a thickening of the old cataract skin. This is the common PCO - posterior capsular opacification.

Patients affected with reduced vision should contact one of our optometrist for further advice. The plastic lenses can become opaque after cataract surgery, in a process called PCO - posterior capsule opacification. It is a fairly common complication of cataract surgery and its treatment is simple and painless. The skin of the cataract which is left after surgery can sometimes thicken and degrade vision. A laser procedure is done in the outpatient clinic, which removes some of the thickened cloudy lens capsule. Treatment is quick and effective, returning vision to what is was like just after surgery. 

The Oculentis implant sits behind the iris, in place of the cloudy natural lens.
The clouded implant lens, currently under recall.

Should the plastic lens by the problem a referral will be made. An ophthalmologist will advise on the best course of action and whether lens exchange would be an option. In some patients, the eye is too fragile and further surgery would not improve vision.

800 people are thought to be affected. Oculentis, the lens manufacturer claims there may be a problem with interaction the lens surface. There is evidence some people may be predisposed to the problem or even that certain medications are playing a factor. 

OCT scan of the retina. The dip is a natural occurrence, where central vision is located. Imaged beneath are small, black void like spaces. These are filled with fluid and is called, macula oedema. 

An OCT scan of the other eye, in the same patient. The natural valley or dip for central vision, without any oedema or fluid filled spaces.

It is important to rule out macula oedema as the cause of reduced vision post surgery. Patients should undergo a thorough slit lamp examination and have an OCT scan. Which immediately shows any fluid or swelling in the macula, which is the part of the retina used for central vision. Macula oedema or fluid in the retina is a possible complication of surgery and should be checked an monitored. 

If you are experiencing any degradation in vision, come and speak to one of our optometrists who will complete a comprehensive post surgery check. OCT scans are now available at all of our practices.