disability Archives - The Red Haired Girl with Glasses

DISCLAIMER:  This article is in no way intended to provide medical advice or treatment.  I am not a physician, nor a medical professional of any sort.  This information is provided solely based on my knowledge, research and understanding as a layperson and former assistant in an eye clinic approximately 30 years ago.  The links to various creditable websites provide valid information but should be discussed with your personal medical professional to determine if it is relevant to your specific circumstances.  The information provided is also based on my understanding of things as they have been explained to me by my past and present physicians.  If you are experiencing any changes in your vision or are in need of medical attention, go to your nearest medical facility or call 911.

Introduction

I’ll try not to get too technical but I also want to share enough information to help you understand more about my vision disorder. So, bear with me and hopefully I can give you enough information to”see the big picture” with CORD-5. (Yes, all puns intended! lol!) I’ll begin this posting with a brief explanation of what “CORD-5” stands for, a short description of the anatomy of the eye, how CORD-5 impacts vision and a little information about the genetic research that has identified the specific gene causing this problem. I’ll wrap up with what this may mean in terms of treatment, therapy and prognosis.

What Does “CORD-5” Stand For?

Briefly, CORD-5 stands for COne Rod Dystrophy – type 5; over time, it has been shortened to CORD-5. It is a rare genetic disorder that causes vision loss and blindness. It affects the cones and rods, which are all located in the macula and retina in the back of the eye.

Brief Anatomy of the Eye

When we look at something (tv, book, trees, birds, people, clock, etc.), the image is received through the cornea, the pupil and lens, and is projected onto the retina. The retina then sends signals through the optic nerve to the brain and the brain interprets those signals as the image we are looking at. While this is a simple summation of how we see, the following two sections will give a little more detail on the parts of the eye and their basic functions.

If you would like more detailed information on the eye and how it works, the American Academy of Ophthalmology provides more details and some good visual illustrations on this page.

Anterior Section

The anterior (front) section of the eye consists of the cornea, iris, pupil, lens and the angles. (Not angels… The little angels are who you see when the grands come to visit. lol!).

The cornea is the clear front part of the eye. It protects the eye from foreign objects, dust, etc., and it also affects the focus of the images we see. The shape of the cornea is one factor in how well we see. If a cornea is misshapen, it can cause astigmatism. The iris (the colored part of the eye) dilates or contracts to adjust how much light passes through the pupil (the black center of the iris) to the back of the eye. In low light settings, the iris dilates to let more light in; in brightly lit settings, it contracts to reduce the amount of light coming into the eye. (During an eye exam, a physician may dilate your eyes with drops to keep the iris open. This helps them assess the health of the back of your eyes.) The two sections of the eye are seemingly separated by the lens, but the lens is still considered part of the anterior section. The lens also helps with the focus of the image we see. The angles control the pressure of the eye. If the pressure is too low or too high, it can damage the optic nerve and cause vision loss. This is known as glaucoma.

Keep in mind that, due to various factors, not all eyes are “created equal.” Between the cornea, the lens, the natural shape of the eye and other factors, some of these may not work or be formed properly which causes us to need glasses, contacts or other type of eyewear to see well. Sometimes, a person may even require surgery to correct the vision or eye problem (cataract, Lasik, glaucoma, etc.).

Posterior Section

The posterior (back) section of the eye includes the vitreous, the retina, the macula and the optic nerve, among other parts which are not relevant to this topic. Again, this is a very brief description of the eye anatomy.

Interesting fact:  The optic nerve creates a blind spot in our vision.  Yep!  Sure does.  This is because the optic nerve has no photoreceptors.  But, because of the amazing ability of our brain to adapt, we just don't notice it.  Also, it is not the central part of the back of the eye; it is slightly off-center.  So, if you were to have a visual field test performed, everyone of us would have a small circular area, slightly off center towards the temples where we see nothing at all.

The posterior section is filled with a “jelly like” substance called vitreous. While it is normally clear, sometimes (due to age, trauma or other issues) it can develop “floaters,” “shadows” or “gnats” created by a change in the consistency of the vitreous. Generally, floaters are nothing more than a nuisance; although, there are times when floaters are caused by blood in the eye from a retinal tear or other disease. Any disturbance or change in your vision, flashing lights, vision loss, bleeding in the eye, retinal tear or detachment (like a veil covering part of your vision) requires immediate medical attention. Contact your medical or vision provider immediately.

The retina is the lining of the back of the eye. It is a vascular tissue which facilitates blood circulation to the eye, contains cones and rods, is home to the macula and is the connective tissue to the optic nerve. Keep in mind that there are a number of diseases and disorders that can affect your vision. If you notice any vision changes, contact your vision professional immediately. It could be a sign of a significant problem which, if left untreated, can cause permanent vision loss.

While I’m not exactly sure, I’m guessing the retina probably contains millions of cones and rods. The cones detect color, while the rods detect the amount of light. The cones and rods send signals (neural impulses) through retina to the optic nerve which travel to the brain. The brain then interprets the signals as the image we see. If someone is color blind, the cones either do not send appropriate signals to the brain or they are unable to perceive the colors correctly. When someone is light sensitive or has trouble seeing at night, the rods are not working properly or are not sending appropriate signals to the brain. In both cases, the brain is not able to interpret the signals correctly, thereby creating an inaccurate or flawed perception of what they are looking at.

Roughly in the center of the retina lies the macula. The macula also contains cones and rods, but is responsible for our fine, central vision (our straight-ahead vision) as well. For example, if you look straight ahead at a clock on the wall, you will see the clock on the wall. Peripheral vision is our “side vision.” This is what is seen outside our central “straight-ahead” vision. An example might be if you’re at the park and a ball comes soaring in your direction, you will hopefully see it in your peripheral (side) vision before it comes into your central vision and bonks you in the face… especially if no one yells, “heads up!”, “look out!” or “duck!” lol! Most people are familiar with the eye disease macular degeneration and, most of the time, this is an age-related issue. As we get older, our bodies tend to naturally deteriorate; this includes the eye. And, as the name states, the macula degenerates (deteriorates) and the central vision is affected or lost. While there is new medical research and treatment for some types of macular degeneration, it may not treat all forms of it. This is something a qualified vision provider can determine for you.

Interesting fact:  A (human's) normal visual field ranges from about 150-170 degrees horizontally and approximately 90 or so degrees vertically.  About 30 degrees in the center comprises the central visual field.  Check out NIH, Nat'l Library of Medicine for more information about Visual Fields.   On this NIH webpage, if you look at Figure 116.1 and compare it to Figure 116.4 (A), you will see the difference between a normal visual field and one with central vision loss...  this includes CORD-5 and  macular degeneration vision loss, among other possible diagnoses.  You can find a simpler description of a visual field test here (Cleveland Clinic).  Also, a great screening tool for macular degeneration or other visual field loss is the Amsler Grid.  You can find information about the Amsler Grid here (Cleveland Clinic).

Finally, there is the optic nerve. As mentioned earlier, the optic nerve connects the eye to the brain via the central nervous system. While the optic nerve has no photoreceptors and can not send signals of images, it is an integral part of our vision. It can become damaged or diseased, which ultimately will affect our vision. While it was previously thought to be irreparable, new technology and science is finding that there may in fact be treatment for damaged optic nerves. Check out this article from Johns Hopkins about optic nerve repair.

Effects of CORD-5

As you may have gleaned from my previous post, “My CORD-5 Journey,” CORD-5 is a genetic disorder affecting the cones and rods in the retina and macula. To recap that post, CORD-5 did not start becoming evident for me until my mid-twenties and it was mild at that time. For several more years I did not have any other significant issues except increasing light sensitivity and slightly decreased visual acuity. In my late thirties to mid-forties, I began to have more significant issues with my visual acuity, color blindness and some mild, but noticeable, central vision loss. Now, in my fifties, I am legally blind with “significant central vision loss,” “significantly impaired visual acuity,” and impaired color vision.

For some people with CORD-5, their vision is only mildly impacted. For others, they are affected much more significantly. Some are affected at a younger age (my dad was legally blind at 27 years old) while others are not affected until later in life. So, the predictability factor of the effects and timeframe for CORD-5 is very random. Some of this may be due to the nature of CORD-5 and, at this point, likely becomes more technical and delves deeper into the science of genetics, but I am not an expert, amateur or even a beginner geneticist so I will not attempt to dissect that in any way, shape or form. lol!

But, these things are true of CORD-5:

it affects the cones and rods;
it affects the macula and central vision;
it affects visual acuity;
it is unpredictable in the degree and timeframe of manifestation.

Genetic Research and GUCY2D… huh?

In the mid 1990’s, my family came into contact with Dr. Kent Small. (Dr. Small is still in practice at the Dr. Kent W. Small Macula & Retina Institute.) Dr. Small is an ophthalmologist who was involved in genetic research with our family and another family with CORD-5.

I believe my first encounter with Dr. Small was fairly basic with him taking a blood sample and performing a basic, rudimentary vision evaluation. After that visit, Dr. Small had some of the family members (including myself) travel to Charleston, SC, to have more extensive testing performed. I do not recall the name of this facility where we had the testing and I’m not sure how many of my family members went, but there were several of us. One of the tests performed was an ERG (electroretinogram). I remember this test specifically because, although not “painful,” it was uncomfortable due to the “wired contacts” placed over the eye, the electrodes attached on my head and the bright, flashing lights. This test was used to evaluate the retinal signals and activity. Another test that was performed was a color vision screening test. For this test, they presented us with several trays containing plastic “caps” with different colors on the caps. We were to put the caps in order by color. Funny story about the color vision test… One of my family members completed that test first and, after I completed mine, I asked her if she knew how she did on that test. She said she did pretty good because she figured out that there were numbers on the bottom of the caps to put them in order. Whoa… Wha???!!! OMG!!! SMH!!! I had no idea about that and, yes, I did VERY poorly on that test. lol!

The next encounter with Dr. Small was maybe a couple years later with a trip to UCLA Jules Stein Eye Institute for more testing. I believe the testing lasted 1 1/2 days and, for the remainder of the trip, we were able to rest and do a little sightseeing. We took a short trip to see some celebrity homes and then went to the Coast. (Yes, I actually waded in the Pacific Ocean! Woohoo!! I don’t remember much about the celebrity homes though because I was in the back seat of the van trying not to get car sick! lol!) Some of the testing was the same as what we did in Charleston, SC, possibly to confirm the previous results and to determine if there had been any progression of the CORD-5.

From the testing Dr. Small did on our family and another family, he and his colleagues were able to identify the gene that presents the CORD-5 anomaly. The gene is identified as GUCY2D. (Apparently some pronounce it “gucky 2D” while others pronounce it “Gucci 2D.”) To the best of my memory, as Dr. Small explained it to me, this is an autosomal dominant gene. And, if I understood correctly, a dominant gene can/will manifest even if there is only the one gene present, from either parent; alternately, a recessive gene will not manifest unless two genes are present, one gene from each parent. Additionally, it is my understanding that if this gene “skips” a generation or individual, then it will no longer be present in that bloodline for future generations. An example of this is my great aunt. Her two brothers both had the gene but she did not. None of her children have the gene or the vision problem. Yet, her brothers and their children and some of the grandchildren have the gene and the vision problem.

Here are links to the two reports Dr. Small and his colleagues collaborated on and presented regarding the CORD-5 research. 1) Identification of GUCY2D ; 2) Clinical Study of a Large Family These reports present the lineage of the two families studied and the presence or absence of the gene in participants, as well as the manifestation of CORD-5 in the participants.

Here are some links to a couple of other sources with information on various cone-rod dystrophies, CORD-5 and CORD-6… 1) University of Arizona; 2) OMIM-CORD5; 3) OMIM-CORD6

One interesting fact that I have learned from Dr. Small’s reports, and from the information on the other sites, is that CORD-5 and CORD-6 are actually the same genetic disorder. This was noted in the first of Dr. Small’s reports linked above. One of the websites does report that CORD-5 is on chromosome 17q13 while the other one for CORD-6 reports it on chromosome 17p13. I am not sure if this is a “typographical” error or if it is an actual genetic/chromosomal difference but, essentially, all of the resources report CORD-5 and CORD-6 as the same disorder.

What now?

As mentioned previously, I am now legally blind. It does take me longer to do most things, whereas someone with good vision can do them much more quickly. As difficult as it can be to accept, I know that this vision issue has the potential to continue to worsen as I get older. I do not anticipate becoming totally blind, but I am trying to prepare (as much as I possibly can) for a “worst case scenario” in the event it does get to that point. (I was briefly a Boy Scout mom and am the daughter of a U.S. Marine… be prepared.)

Accommodations are the name of the game now. I use visual aids and assistive technology, including magnifiers, computer glasses, a CCTV (closed circuit tv), filters (sunglasses) and tinted glasses lenses. With the progression of technology, I am able to adjust the settings on my computer to an “inverted” high contrast setting where there is a black background with white font, as well as an enlarged display setting. I have not yet become comfortable with “reading” software, but may further explore that option in the future. I prefer digital material to printed material, mostly because I can enlarge the font/text size and invert the colors on my tablet and laptop. I have recently acquired a white cane and am learning to use it when I go places I’m not familiar. (It is also a great visual cue to others that I am blind/visually impaired and may need assistance.). I am learning to utilize public transportation services and will hopefully become more adept at that soon. I rely on my husband, family and friends to guide me in unfamiliar locations… And, along with that, I am learning to laugh at myself more when I miss a step or stumble over a sidewalk/curb I don’t see. Fingers crossed I don’t break a leg or my neck when this happens. lol! Sometimes it’s also laughing at myself for dressing funny… or getting one thing when I think I’m getting something else… or thinking a piece of lint on the floor is a bug and I squeal… lol! An embarrassed ego heals pretty quickly with some good-hearted laughter. lol!

Next, I have an appointment in August (2024) to visit Wills Eye Hospital in Philadelphia, PA, for an evaluation and genetic counseling. It is my understanding that this appointment will help determine if I am a candidate for additional genetic research or even possibly genetic therapy/treatment/trials, if there is anything currently available. For me, this trip would be more for curiosity’s sake but there is also a little glimmer of hope that maybe there is research which will provide a “cure” or treatment in the near future. While I can accept that my vision may not be “curable,” honestly, I just pray that there may be genetic therapy that can prevent my children (and other children in my family) from developing the significant vision problems from CORD-5. (Or, better yet, eliminate this genetic disorder from the family completely!) I will try to post an update below after my visit.

While the transition from working and being independent to being “disabled” and dependent has been VERY difficult, it is an adjustment I must make. This condition can not win. Instead of considering myself “disabled,” I am learning to consider myself “differently-abled.” I CAN still do most things I like to do; I just have to do them differently. I absolutely CAN NOT use it as an excuse to stop living my life. I can not let it define or defeat me. I must let it drive me to become more creative in how I do things, to look for new opportunities, to learn to ask for and accept help, to explore and embrace new systems and supports, to advocate for myself and others and to become more resilient in the tides of adversity. I have determined that “growing pains” are to be expected in life and if you stop having “growing pains,” you have stopped living. This doesn’t mean that it will be easy, it just means I will keep getting up when I fall down… every time! Regardless of how long it takes, I WILL get back up. (Yes, this is positive self-talk for myself just as much as it is to encourage others.)

No obstacle is an excuse to stop; it is a reason to grow, to become more resourceful, to challenge yourself and the status quo, to become more flexible, and to become stronger today than you were yesterday.

Thank you for stopping by… Take care and be well!

Rebecca ~~<3~~

Tag: disability

What is CORD-5?