Anesthesia and hypoesthesia of cornea, unspecified eye

This code signifies a reduction or complete loss of sensation in the cornea, affecting an unspecified eye. It indicates a sensory neuropathy of the corneal surface, which can lead to decreased blink reflex and increased risk of corneal injury or infection.

Assign this code when documentation indicates corneal anesthesia or hypoesthesia without specifying laterality (e.g., "corneal numbness," "decreased corneal sensation"). It is appropriate when the underlying cause is unknown or not yet diagnosed, or when the sensory deficit itself is the primary focus of treatment.

• Do not use this code if the laterality (right or left eye) is documented; instead, choose the more specific H18.811 or H18.812.
• Always look for documentation of the underlying cause (e.g., herpes zoster ophthalmicus, trigeminal nerve damage) and code it first if applicable.
• This code is for the sensory deficit itself, not for conditions that cause corneal anesthesia.