H95.139
Mucosal cyst of postmastoidectomy cavity, unspecified ear
H95.139 (also written H95139) is a billable ICD-10-CM diagnosis code for mucosal cyst of postmastoidectomy cavity, unspecified ear. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 36 codes in category H95 (Intraoperative and postprocedural complications and disorders of ear and mastoid process, not elsewhere classified). Its coding notes include 8 Excludes2 entries.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Intraoperative and postprocedural complications are coded from the body system chapters unless the complication is specifically indexed to a T code.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (8 notes)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
Also from chapter/block level (1 note)
- Use an external cause code following the code for the ear condition, if applicable, to identify the cause of the ear condition