ICD-10-CM > H60-H95 > H65-H75 > H70 > H70.9 H70.9 Unspecified mastoiditis Non-Billable/Non-Specific Codes H70.90Unspecified mastoiditis, unspecified earH70.91Unspecified mastoiditis, right earH70.92Unspecified mastoiditis, left earH70.93Unspecified mastoiditis, bilateral