Q18.5
Microstomia
Billable FY2026 2025-10-01 → 2026-09-30
Exclusions 14 never code together
Q18code
Excludes1
- cleft lip and cleft palate (Q35-Q37)Q35-Q37
- conditions classified to Q67.0-Q67.4Q67.0-Q67.4
- congenital malformations of skull and face bones (Q75.-)Q75.-
- cyclopia (Q87.0)Q87.0
- dentofacial anomalies [including malocclusion] (M26.-)M26.-
- malformation syndromes affecting facial appearance (Q87.0)Q87.0
- persistent thyroglossal duct (Q89.2)Q89.2
Q10-Q18block
Excludes2
- cleft lip and cleft palate (Q35-Q37)Q35-Q37
- congenital malformation of cervical spine (Q05.0, Q05.5, Q67.5, Q76.0-Q76.4)Q05.0Q05.5Q67.5Q76.0-Q76.4
- congenital malformation of larynx (Q31.-)Q31.-
- congenital malformation of lip NEC (Q38.0)Q38.0
- congenital malformation of nose (Q30.-)Q30.-
- congenital malformation of parathyroid gland (Q89.2)Q89.2
- congenital malformation of thyroid gland (Q89.2)Q89.2
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes
No further instructional notes apply.
Index entries leading here 1
- Microstomia (congenital) Q18.5
Alongside this code 9 same parent — Q18
Q18.0 Sinus, fistula and cyst of branchial cleft Q18.1 Preauricular sinus and cyst Q18.2 Other branchial cleft malformations Q18.3 Webbing of neck Q18.4 Macrostomia Q18.6 Macrocheilia Q18.7 Microcheilia Q18.8 Other specified congenital malformations of face and neck Q18.9 Congenital malformation of face and neck, unspecified
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.