Why Is This Canadian Family Going Blind? Eye Doctor Explains 

I love the intro, Dr. Wong!!! I’ve been a long time fan of yours.

Very informative! A friend lost her vision while a teen in high school. It's interesting to learn about this condition.

Hi Dr. Rupa Wong. Wonderful video. A slight correction though. AD is actually the least severe and has the best prognosis. X-linked has the worst prognosis. Love watching your videos. Always informative. Keep up the good work.

Wow . . .so doc Rupa I remember in the summer that I was thinking of leaving you a comment about maybe following their story and sharing about it here. I do not even know if I did it 'cuz summer was i.n.s.a.n.e. here with immense heat and 'still' is with no rain and I am on the shore in the normally 'Wet Coast' zone along the Salish Sea. So glad to see you share about these folks. What immense challenges they are going to face in the future...but what a true vision of a 'family'. They are from Quebec.

Please Read this Explanation of RP: Don't let any terms discourage you, just follow the main concepts. Vision detection is a long series of proteins that work in concert to effect an electrical signal that is carried away from the nerves in the retina, eventually joining into the Optic Nerve and carried to the brain for interpretation. If any protein is incorrectly coded (the protein recipe is written on our DNA segments), it can cause that pathway to eventually fail at any point along its journey. Inherited Retinal Dystrophies (or Diseases) are a disease of 300+ DNA mis-coding (incorrect recipes) being passed from generation to generation through all of the forms of inheritance. There are also spontaneous mis-codings that rarely happen, because of chemicals, radiation, or a mistakes during ongoing DNA replication within the Cell Nucleus, etc. The Retina has several layers. The main layers of importance to understand in RP (IRD) are the "Photoreceptor Layer" and its underlying "Retinal Pigmented Epithelium Layer (RPE)." The Photoreceptor Layer" is made up of Rods (for low light detection in black, grey or white) and the Cones (normally 3 types , red, blue and green) for Color detection. The brain determines the secondary and tertiary colors and hues (ex: purple) by how strongly each of the 3 cone types are stimulated. If for example, the blue and red cones are stimulated the brain interprets it as purple. They are collectively known as PHOTORECEPTORS, it takes one photon of light to stimulate a Rod Receptor and several hundred photons to stimulate a Cone Photoreceptor. Think of the Retina as a bullseye target. with rings. The outer ring is almost entirely Rods, as you move into the central rings Cone are intermingled with the Rods. Until you reach the inner most ring (the Macula as it gives us our greatest Central Vision) which is almost entirely Cones and within the central most point of the Macula there is a pit (the Fovea) of solid Cones with no rods. That is the area of our eye that gives us the best visual acuity (focus) and detection of fine movement. And because the Macula and the Fovea are almost entirely Cones, that is why in IRD's we are still able to have color detection and somewhat preserved vision until they are the last to fail, due to overwhelming failure of the RPE. Oddly enough, the Rods and Cone actually point toward the back of the eye and are in intimate contact with the single cell protective layer (RPE) that wraps around the inside of the eye except in the front near the lens and iris. The (RPE) Retinal Pigmented Epithelium: This one layer thick cell wrap has 6 sided shaped cells (like a bee hive honeycomb) each of the sides has a thick coating of a cellular glue at the inner edge, between each cell that causes a seal or tight barrier of protection between the cells and thus protects the retina from the underlying blood vessel rich layer (the Choroid). This is what forms the "Blood-Retinal Barrier" preventing anything of a certain size, from entering the internal eye. (ex: autoimmune antibodies that would attack and destroy the eye. That is why in some clinical trials of injecting DNA segments or even stem cells, in hopes to repair mis-coded DNA, there is no autoimmune rejection.) The RPE is extremely important in its function to supply nutrition to the Retina and carry away waste from the highly metabolically active rods and cones. The RPE has finger like projections (microvilli) that extend from the surface of the RPE Cell into and around the Rods and Cones to help maintain an environment to feed, protect and remove waste. The RPE also makes certain proteins necessary for vision. ex: the protein that is mis-coded (RPE65 gene) in Leber's Congenital Amaurosis Type 2 [LCA2] (that gene carries the message how to make retinoid isomerohydrolase within the RPE). Each RPE Cell also contains hundreds of granules of a pigment called "Melanin." These pigmented cells help prevent the rods and cones from being overstimulated by the light entering the eye. The Melanin absorbs the excess light and prevents light scatter all of which would "white out" the retina if not dampened by the Melanin in the RPE Cells (like a snow storm white out). The Melanin also absorbs damaging UV light that can can result in free radicals that bind with the intracellular oxygen of the RPE Cells, leading to RPE Cell death. In RP the waste removal done by the RPE can be overwhelmed by the rods & cones dying off and damaging the RPE in the process of trying to remove the resulting waste (in addition to other causes). This damage results in the RPE Cells rupturing and spilling their "Melanin Pigments" into the surrounding Retinal Layers. This is what causes the darkened splotches or spots on the retina that is diagnostic of RP. Also, the Rods secrete a "neuroprotective substance" that coats the nearby cones (Rod-derived cone viability factor (RdCVF), so that when the Rods die the nearby cones also die and add to the workload of the RPE to remove the waste leading to more of the RPE Cells rupturing, also spilling their Melanin Pigment. After much of the RPE is destroyed, it is no longer able to keep up nourishing the remaining Rods and Cones so that more and more Rods die, mostly the Rods which are in the highest numbers at the outside circle of the Retina. Since the Rods give us night vision and our peripheral vision. The early symptoms of RP are "loss of night vision" and "narrowed visual field" (tunnel vision). And of course the appearance of the "Melanin staining of the Retina". These are the 3 cardinal symptoms of RP or Inherited Retinal Dystrophies/Diseases (IRD's is the new name, because we now know that RP is not just one disease but each type having a different genetic cause.) There is much more to this process depending on the genetic causes. But, the end result is almost always the same...Photoreceptor Death, RPE destruction (spilling the Visual Pigment Melanin) and increasing night vision loss, lead to increasing overall visual failure with time.

Hi! Love your videos! Can injecting hyaleronic acid filler beneath the brow cause blindness? What treatment would you recommend to restore volume of the upper eyelid?

Thank you

Thanks

there are entire Canadian towns where everyone is blind. also, i got mine fixed in Florida but they still never worked right.

I wonder if an eye transplant may be possible? I dont know if this even exists yet?

I got diagnosed with retinal degeneration please any help for me

hi didi, fantastic. to inform u, my parents have returned from the USA after attending my sister's Indian Taiwanese marriage.

Any help to slow RP please doctor

I got diagnosed with RP

Hey doctor! I have heard that plasma rich platelets or PRP injection may help to slow down the progression of RP in some cases Can you guide me about this.

it’s not just ”night blindness.” i hate reading that garbage.

Im 47 years old

In Canada RP treatment is available there is wellspring clinic

Hi Maminita Dembele