ICD-10 Code H55.04 – Dissociated nystagmus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H55.04 – Dissociated nystagmus
What it is
Dissociated nystagmus is an abnormal eye movement disorder in which the two eyes do not move together in the same direction or with the same intensity. Use this code when documentation specifically identifies this form of nystagmus.
Clinical signs
Clinical features vary; refer to documentation. Typical notes describe unequal, disconjugate rhythmic eye movements, often observed on examination or with gaze changes.
When to use this code
Use H55.04 when the provider documents dissociated nystagmus as the diagnosis. It may appear in ophthalmology or neurology records, especially when the exam distinguishes it from other nystagmus types. If the chart only says “nystagmus,” check documentation for the specific subtype.
Do not use for
Do not use this code for unspecified nystagmus or other clearly named nystagmus variants. Check documentation if the record refers to a different eye movement disorder or an unclear finding.
Coding tip
Assign H55.04 only when the subtype is explicitly stated; otherwise, query for clarification.