Congenital night blindness

This code signifies a condition present at birth where an individual experiences impaired vision in low light or darkness. It is characterized by difficulty seeing at night or in dimly lit environments due to a congenital defect affecting the retina's ability to adapt to changes in illumination.

Apply this code when documentation explicitly states "congenital night blindness" or "hereditary nyctalopia." This diagnosis is typically supported by an ophthalmological examination confirming the presence of night blindness from birth, often without other significant ocular pathology.

• Differentiate from acquired night blindness (e.g., due to vitamin A deficiency), which would use a different code.
• Ensure the documentation specifies "congenital" to support the use of this particular code.
• Consider co-occurring genetic conditions or syndromes that may be associated with congenital night blindness and code them separately if present.