ICD-10-CM > S00-T88 > S00-S09 > S00 > S00.2 > S00.22 > S00.221 S00.221 Blister (nonthermal) of right eyelid and periocular area Non-Billable/Non-Specific Codes S00.221A..., initial encounterS00.221D..., subsequent encounterS00.221S..., sequela