Retinitis Pigmentosa - Night Blindness

Night blindness is a retinal disease. The retina is the web layer that allows us to see and can be thought of as a wallpaper that fills our eyes. Night blindness is a disease caused by damage to the light-sensing layer of tissue cells in the retina due to genetic mutations. While it causes loss of vision at first, it can also cause daytime vision loss in older ages. Its incidence is known as 1/3000 and 1/4000.

What Causes Night Blindness?

Night blindness is caused by damage to the cells in the retina. The disease usually occurs for genetic reasons. In addition, consanguineous marriages also increase the risk of developing this disease, as it increases the likelihood of two recessive genes coming together.

 

What Are the Symptoms of Night Blindness?

Difficulty seeing in dim light (night) (nyctalopia), vision difficulty in daylight in later stages

Narrowing in the visual field

Specific eye symptoms (bone speculations, attenuation in retinal arterioles, optic disc pallor in wax appearance)

Electroretinogram findings indicating photoreceptor cell dysfunction in the retina

Night blindness disease may be accompanied by cataracts, edema in the visual center, refractive errors such as myopia-astigmatism, eye diseases such as keratoconus and glaucoma.

How Is Night Blindness Treated?

The course of the disease is different from patient to patient, even among different members of the same family.

Studies are still ongoing on the accepted definitive treatment of night blindness.

In the treatment protocol, the main purpose is to slow the progression of the disease and increase the adaptation of the patients to social life.

It has been proven that taking 15.00 vitamin A per day significantly slows the course of the disease.

Carotenoids lutein and β-carotene have a limited effect on slowing the progression of night blindness.

Gene Therapy 

Gene therapy is meaningless in later periods when photoreceptors are completely dead. It is more effective in cases detected at early stages.

To the first approved gene therapy in 2017, the U.S. Food and Drug Administration (FDA) approved voretigene neparvovec zrzyl (Luxturna), a gene therapy used to treat rare hereditary blindness. Although it is widely described as a 'visionavavist' therapeutic treatment by the media, it is a very costly treatment. It can be used for patients with mutations in the RPE65 gene on both chromosomes. Luxturna is given as a single injection under the retina to the back of each eye. It was observed that the patients who received this treatment increased their adaptation to night vision, walking and disability.

Stem Cell Therapy

Researchers are of the opinion that transplanted stem cells can differentiate into retinal cells and integrate into patients' retina and differentiated stem cells will replace apoptotic or damaged retinal cells.

 

Growth Factor Injections

In this way, programmed cell death can be manipulated and healthy retinal cell life can be extended. Studies on this subject gave positive results on vision prognosis in night blindness. In our clinic, sub tenon PRP application, which contains abundant growth factor, prepared from the person's own blood, is performed by us.

 

Ocuvision  

Low-dose electrical stimuli are sent to retinal cells, and these stimuli increase the release of neuroprotective growth factors from retinal cells. Thanks to these released factors, the cells in the retina are protected and vision loss is stopped in the patient. Application should be done once a week.

Protective Glasses

It is recommended to block the blue light spectrum, reduce the discomfort from the light, increase the contrast sensitivity, but it has not been seen to affect the course of the disease.

Treatment of Complications

Treatment of concomitant cataracts and vision center edema increases the quality and level of vision.

 

Hyperbaric Oxygen Therapy

It is emphasized that visual acuity contributes to the stabilization of visual field and visual functions.

Nutrition And Healthy Lifestyle Advice

Protection from the sun, Mediterranean type nutrition, walking for 30 minutes outdoors every day, never smoking cigarette, avoiding alcohol.

Retinal Prosthetics

It is applied at the stages of the disease that is very advanced and vision decreases. It can be used to detect the silhouette of the remaining retinal neurons and convert them into electrical stimuli by using artificial devices, to reveal the neural activity, it can be provided by using devices placed surgically on various layers of the eye.

 

Low Vision Rehabilitation Devices

Telescopic glasses illuminated magnifiers or camera magnifiers respond well to patients' reading needs, especially in patients with good vision.