ICD-10 code for ear external cyst

The ICD-10-CM code for ear external cyst is Q18.1 (Preauricular sinus and cyst).

Within Q18 (other congenital malformations of face and neck), Q18.1 is specifically for preauricular sinus and cyst. Related codes cover sinus, fistula and cyst of branchial cleft (Q18.0), other branchial cleft malformations (Q18.2), Webbing of neck (Q18.3), Macrostomia (Q18.4), Microstomia (Q18.5), Macrocheilia (Q18.6), Microcheilia (Q18.7), other specified congenital malformations of face and neck (Q18.8) and 1 more.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 154 (Other Ear, Nose, Mouth and Throat Diagnoses with MCC, relative weight 1.5921), DRG 155 (Other Ear, Nose, Mouth and Throat Diagnoses with CC, relative weight 0.9322) and DRG 156 (Other Ear, Nose, Mouth and Throat Diagnoses without CC/MCC, relative weight 0.6659), in MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth and Throat), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.