ICD-10-CM > H60-H95 > H95-H95 > H95 > H95.1 > H95.13 H95.13 Mucosal cyst of postmastoidectomy cavity Non-Billable/Non-Specific Codes H95.131Mucosal cyst of postmastoidectomy cavity, right earH95.132Mucosal cyst of postmastoidectomy cavity, left earH95.133Mucosal cyst of postmastoidectomy cavity, bilateral earsH95.139Mucosal cyst of postmastoidectomy cavity, unspecified ear