General Information on Night Blindness (Retinitis Pigmentosa)
Disease Details and Frequently Asked Questions
It is a genetic disorder where the light-sensitive cells (rods and cones) located in the posterior wall of the eye (retina) gradually degenerate, break down, and plunge the individual into darkness due to a specific genetic coding error.
Due to their physiological structure, chickens cannot see their surroundings when it gets dark. Because the first cells to die in this disease are the rods, which facilitate vision in low-light conditions, patients become blind at dusk or in dim lighting, much like chickens.
Cell death initiates at the peripheral edges of the retina and progressively advances toward the center. The patient loses peripheral sight (cannot see to their right, left, or under their feet) and bumps into objects. Eventually, only a narrow, constricted visual field remains, as if looking through a tight pipe or tunnel.
The disease progresses very slowly (over decades). Unfortunately, by the time most patients reach 40-50 years of age, their central vision is also compromised, culminating in legal or total blindness.
Diagnosis is suspected when an ophthalmologist dilates the pupils and observes pathognomonic 'bone spicule' pigment deposits within the retinal cells. An ERG (Electroretinogram) test provides definitive proof by demonstrating diminished electrical signals in the retina.
Currently, there is no standard pill or surgical cure that can arrest cell death or regenerate dead cells. However, high-dose Vitamin A supplementation may marginally decelerate progression. In highly selected, suitable end-stage patients, an Argus II (Bionic Eye / Retinal Implant) surgery can restore basic light and silhouette perception.
Our health library contents are prepared for informational purposes only and with scientific data available at the time of recording. For all your questions, concerns, diagnosis, or treatment regarding your health, please consult your doctor or a healthcare institution.
