Internuclear ophthalmoplegia, right eye

This code describes a neurological condition affecting the right eye, characterized by impaired adduction (inward movement) of the right eye during conjugate gaze, often accompanied by nystagmus in the abducting (outward moving) left eye. It results from a lesion in the medial longitudinal fasciculus (MLF) on the right side.

Use this code when documentation clearly indicates a diagnosis of internuclear ophthalmoplegia specifically affecting the right eye. This typically occurs in patients presenting with diplopia, gaze abnormalities, and often points to underlying conditions like multiple sclerosis or brainstem stroke. Supporting documentation should include neurological examination findings confirming the right-sided adduction deficit and contralateral abducting nystagmus.

• Ensure the laterality is explicitly documented as "right eye" to support this specific code.
• Do not confuse with other types of ophthalmoplegia or gaze palsies; differentiate based on the characteristic MLF lesion signs.
• Always code any underlying neurological condition (e.g., multiple sclerosis, stroke) as a primary diagnosis when applicable, with internuclear ophthalmoplegia as a secondary diagnosis.