From the minute we wake up until we go to sleep, our eyes help us navigate the world. Like a finely tuned camera, each part of our eyes has a very specific job to do.
What is hereditary retinal dystrophy (IRD)
Our domed cornea, the front layer of the eye, lets in light and bends it to help us focus. A little light enters through the small opening of the pupil. The amount of light the pupil can let in is controlled by the iris, the colored part of the eye. This light then passes through the lens of the eye, which works with the cornea to focus the light onto the retina. The retina, located at the back of our eye, is sensitive to light. It contains special cells called photoreceptors that convert light into electrical signals that go to your brain and turn those signals into images that you see.
Sometimes things can go wrong with one of the parts of our eyes. A rare group of disorders affecting the retina are called hereditary retinal dystrophies (IRDs). These groups of diseases are hereditary, meaning they are passed down through families. The cause is mutations, or malfunctions, in at least one gene that is not working properly. There are about 300 known to play a role in these diseases.
Some IRDs may progress slowly, while another may change vision much faster. Some can cause vision loss.
Why is an early diagnosis of IRD useful?
“It is important to understand that these diseases are rare, relatively speaking. But for people who have IRD, it can be life-changing,” says Shree Kurup, MD, FACP, retina specialist at University Hospitals Cleveland Medical Center. “But what’s important to know is that early diagnosis of any of these diseases can absolutely improve lives. We may not be able to cure all IRDs, but we are making significant progress in learning more about the hundreds of genes that can cause them.
There are over 260 genes that can cause IRDs. But getting a diagnosis is more complicated than a routine eye exam. “There can be many reasons for blurry vision, and an IRD won’t be an ophthalmologist’s first thought,” says Matthew MacCumber, MD, PhD, retina specialist at Rush University Medical Center. There is a wide variety among all IRDs, so it can be difficult to make an accurate diagnosis. “Sometimes patients can be misdiagnosed for years and when they finally get a firm, accurate diagnosis, it’s almost a relief because they can finally put a name to their problem,” MacCumber says.
To make a diagnosis, doctors rely on a battery of specialized tests that give them information about many aspects of your vision. A genetic test will tell you exactly which genetic mutation you have and can help your doctor confirm your diagnosis. It will also provide you and your family with important information about your illness, how you may need to plan for your own future, and how it may affect other members of your family and future generations. .
“It’s important to spend a lot of time with people to explain how an IRD can change their lives,” says MacCumber. “Early diagnosis also gives patients early access to a team of experts who can help them.” This team is made up of ophthalmologists, optometrists, retina specialists, genetic counselors and other low vision experts.
Early diagnosis and clinical trials
Early and accurate diagnosis can also help you enroll in a clinical trial. This will give you the chance to try new therapies before they are available to the general public. Although almost no IRDs have treatments at present, doctors are optimistic about the future of gene therapies. In clinical trials of one of these therapies, patients said they were able to get rid of certain devices designed to help people with vision loss see faces and read.
“Gene therapy is the future of IRDs, and we’ve come a long way in genetic testing. We’re learning more and more about these diseases. I absolutely 100% recommend that patients take part in a clinical trial if they are eligible is how we will find cures,” MacCumber says.
The most important thing for the majority of people with DRI right now is not to lose hope. “Imagine how difficult it can be for a parent to hear that their child may be going blind or how difficult it is for an active adult to hear that they may have to change things in their life,” says Kurup. “IRDs are very complex, but each patient is an individual. For these people, knowledge really is power, and the sooner they get that power, the better.