Q18.1 Preauricular sinus and cyst

Billable ICD-10-CM code, FY2026. Exempt from present-on-admission (POA) reporting.

Applicable to

• Fistula of auricle, congenital
• Cervicoaural fistula

Applies from Q18 Other congenital malformations of face and neck

Excludes1 (never code together)

• cleft lip and cleft palate (Q35-Q37)
• conditions classified to Q67.0-Q67.4
• congenital malformations of skull and face bones (Q75.-)
• cyclopia (Q87.0)
• dentofacial anomalies [including malocclusion] (M26.-)
• malformation syndromes affecting facial appearance (Q87.0)
• persistent thyroglossal duct (Q89.2)

MS-DRG index

Defines the logic of DRG(s) 154-156 in MDC 03.

Approximate ICD-9-CM (GEMs)

• 744.46 Preauricular sinus or fistula (approximate)
• 744.47 Preauricular cyst (approximate)

Code annotations containing back-references to Q18.1

Back-references to Q18.1

• Type 1 Excludes: H70.8 Other mastoiditis and related conditions ("preauricular sinus and cyst (Q18.1)")
• Type 1 Excludes: Q17 Other congenital malformations of ear ("preauricular sinus (Q18.1)")

Back-references to Q18

• Type 1 Excludes: Q75 Other congenital malformations of skull and face bones ("congenital malformation of face NOS (Q18.-)")

Diagnosis Index entries for Q18.1

• Cyst (colloid) (mucous) (simple) (retention) › ear (external)
• Cyst (colloid) (mucous) (simple) (retention) › preauricular
• Fistula (cutaneous) › auricle › congenital
• Fistula (cutaneous) › cervical, lateral
• Fistula (cutaneous) › cervicoaural
• Fistula (cutaneous) › preauricular (congenital)
• Imperfect › closure (congenital) › preauricular sinus
• Sinus › preauricular

Nearby codes

• Q18 Other congenital malformations of face and neck
• Q18.0 Sinus, fistula and cyst of branchial cleft
• Q18.1 Preauricular sinus and cyst (this code)
• Q18.2 Other branchial cleft malformations
• Q18.3 Webbing of neck
• Q18.4 Macrostomia
• Q18.5 Microstomia
• Q18.6 Macrocheilia