Patient: 70 years of age, male BCVA 0.8 at OD, 0.8 at OS, IOP 18/19 mmHg. Ocular Medical History: unclear iridal process detected by slit lamp examination General Medical History: empty Main Complaint: asymptomatic, unclear iris lesion. Purpose: to report a case involving an unclear iris lesion . Methods: Slitlamp Photography, 35 Mhz-Sonography (Sonomed). Findings: Slitlamp Photography: localised distortion of the iris at 3h with narrowing of the anterior chamber. Sonography: multiple cysts of iris pigment epithelium, containing clear fluid. Discussion: Peripheral iris pigment epithelial (IPE) cysts are benign lesions of the anterior segment. IPE cysts classically remain stable without need for intervention. They are located at the iridociliary junction and can produce a localised distortion of the iris. The aetiology is unknown. They tend to be unilateral and solitary . The cyst walls are composed of iris pigment epithelium and the lumen contains clear fluid. Patients are usually asymptomatic. Peripheral iris pigment epithelial cysts must be differentiated from malignancies of the iris or ciliary body. Shields et al. (1) reported the spectrum of iris lesions including 3680 iris tumors in 3451 patients. In this study of 3680 tumors, the diagnostic category was solid (79%) or cystic (21%). The cystic tumors originated from iris pigment epithelium (18%) or iris stroma (3%). The solid tumors included nevus (60%), melanocytoma (3%), melanoma (26%), and melanocytosis (3%). They concluded that the most common specific diagnoses of iris lesions were nevus (42%), iris pigment epithelium cyst (19%), and melanoma (17%). Literature: (1) Shields, CL; Kancherla, S; Patel, J; Vijayvargiya, P; Suriano, MM; Kolbus, E; Badami, A; Sharma, P; Jacobs, E; Voluck, M; Zhang, Z; Kansal, R; Shields, PW; Bianciotto, CG; Shields, JA. Clinical survey of 3680 iris tumors based on patient age at presentation. Ophthalmology, 2012 vol. 119(2) pp. 407-14