ICD-10 Code J34.1 – Cyst and Mucocele of Nose and Nasal Sinus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J34.1 – Cyst and mucocele of nose and nasal sinus
What it is
J34.1 identifies a cyst or mucocele arising in the nose or a nasal sinus. It describes a localized, usually benign fluid-filled lesion that can expand and affect nearby sinus structures.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include nasal obstruction, facial pressure, swelling, or an incidental sinus lesion seen on imaging.
When to use this code
Use this code when the provider documents a cyst or mucocele specifically in the nose or a nasal sinus. It is appropriate for confirmed imaging or endoscopic findings when the lesion is the reason for evaluation or follow-up. If the note only says “sinus mass” or “nasal lesion,” check documentation.
Do not use for
Do not use J34.1 for unrelated sinusitis, nasal polyps, or abscesses. If the record does not clearly identify a cyst or mucocele, check documentation.
Coding tip
Code the exact anatomic site only when documented, and query if the record does not distinguish nose from a specific nasal sinus.