What can you do to help your vision if you have achromatopsia?
In the last blog post, I interviewed Shahlaa who has been doing a holiday job with us here at Clinica London. She is doing a lot of paper work, scanning documents and putting them on to the computer and when she uses the computer, she uses a magnifying option and works in a slightly dim room, i.e., not in bright sunlight.
Shahlaa is wonderful. She does everything completely normally like everybody else, and of course, for her, it is normal because she has had achromatopsia all her life. The main problem is, in fact, other people not realising that the only problem Shahlaa has is the achromatopsia. This condition gives her marked light sensitivity, reduced detailed vision (daylight vision), and complete absence of colour vision.
It is a non-progressive condition. So Shahlaa knows that what she has got now is what she will have for the rest of her life and she makes the most of it. In this blog post, I share some measures that people with achromatopsia can use to cope with their vision and day to day life at university, profession and family.
What is changing with achromatopsia?
There is no actual cure for achromatopsia, but research with gene therapy is ongoing and will hopefully lead to clinical treatments in the future. If you or your child has achromatopsia, you should first check to see whether you require glasses. In other words, long-sightedness (hyperopia) or short-sightedness (myopia) or astigmatism. Then, glasses alone will help improve your vision, but it will not restore it to normal levels of vision. Some say that red coloured lenses reduce light sensitivity and enhance visual functions. Special extra covering glasses (injection moulded) are made of plastic and are plastic wrap around with a top shield that covers the top of a prescription frame as well as broad side shields also help to keep out stray light. The glasses may be quite darkened and only transmit about 4 to 5% of light, and these are called the CPF-550 or the CPF550-XD lenses.
With achromatopsia, you should be able to attend a normal school. You may want to sit further forward in the class, but now with students increasingly using iPads being in the classroom, the need for large print books and magnifying devices is minimised.
Of course, you should have a low vision evaluation before school starts. There may be some other changes that have to be made for you such as not sitting by the window in bright sunlight. Note that Shahlaa does not need a stick as peripheral vision (side vision) is normal in achromatopsia. She gets around London perfectly well. She wears contact lenses instead of glasses, and she has an extra pair of darkened contact lenses which can help her in bright sunlight. These are specially made contact lenses suitable for people with achromatopsia.
Gene research is targeting the cone cells responsible for decreased vision and decreased colour vision.
These cone cells are right at the bottom of the retina. There are ongoing early phase gene therapy clinical trials using a small surgical cannula through which surgeons deliver a normal copy of one of the two commonly faulty genes in Achromatopsia, CNGA3 or CNGB3 gene, under the retina in close proximity to the cone cells that are being targeted.
There are 2 clinical trials for CNGB3 achromatopsia (one in the USA (AGTC) and one in the UK (MeiraGTx, UCL Institute of Ophthalmology/Moorfields Eye Hospital), and one for CNGA3 achromatopsia (Germany).
It is hoped that gene therapy will help avoid having to wear very dark and heavily tinted glasses and thereby better address the marked light sensitivity that is common in achromatopsia. It is also hoped that it will improve central vision both in terms of detailed vision and colour perception.
People with achromatopsia cannot drive a car and have to take public transport, so overcoming some of those restrictions remains a dream we may see come true within twenty years. Adapting to achromatopsia can enable patients to live without limitations, however, having an improvement of vision in the future through gene therapy will open up their lives even more.