ICD-10-CM > H00-H59 > H15-H22 > H21 > H21.3 > H21.35 H21.35 Exudative cyst of pars plana Non-Billable/Non-Specific Codes H21.351Exudative cyst of pars plana, right eyeH21.352Exudative cyst of pars plana, left eyeH21.353Exudative cyst of pars plana, bilateralH21.359Exudative cyst of pars plana, unspecified eye