Abnormal oculomotor study

This code signifies an abnormal result from a diagnostic test evaluating the oculomotor system, which controls eye movements. It indicates a deviation from normal in the function of the cranial nerves (III, IV, VI) and associated brainstem pathways responsible for coordinating eye motion. This abnormality may be detected through various oculomotor studies, such as electronystagmography (ENG), videonystagmography (VNG), or saccade/pursuit testing.

Assign this code when documentation explicitly states an abnormal finding on an oculomotor study, regardless of the underlying cause. This is appropriate when the study reveals nystagmus, saccadic abnormalities, pursuit deficits, or other dysfunctions of eye movement. Supporting documentation includes the formal report from the oculomotor study performed by an audiologist, neurologist, or ophthalmologist.

• Do not use this code if a specific diagnosis explaining the abnormal oculomotor study (e.g., nystagmus, vertigo, brainstem lesion) is already established and coded.
• This code is for the abnormal finding itself, not the procedure performed.
• Sequence this code after any definitive diagnosis if the abnormal finding is a symptom or manifestation of that condition. If no definitive diagnosis is made, this code may be primary.