Pupillary distortion and staphyloma following trans-scleral contact diode laser cyclophotocoagulation: a clinicopathological study of three patients

Purpose To search for the cause of scleral thinning and pupillary distortio n following trans-scleral contact diode laser cyclophotocoagulation (TCDLC) . Methods We reviewed the records of 3 patients in whom there were complicati ons of scleral thinning and pupillary distortion following TCDLC. One of th e eyes was later enucleated, and we present the histopathological. findings . Using the histopathological features in this patient, we discuss the poss ible pathogenesis of the scleral thinning and pupillary distortion. Results Case 1 is a 46-year-old white woman who following TCDLC in an area of clinically normal sclera developed a staphyloma. Case 2 is a 52-year-old white woman who following TCDLC in an area of scarred sclera developed mil d thinning. Case 3 is an 85-year-old white man who following TCDLC develope d pupillary distortion, and gonioscopy revealed damage to the peripheral ir is. Histological examination of case 1 revealed the staphyloma covered by a thin layer of conjunctival epithelium, collagen and vitreous condensation. We also observed cicatricial cilary body contraction causing distortion of the pupil and lens. Conclusions Therapeutic TCDLC can produce scarring of the iris root, anteri or chamber angle, draining structures and ciliary body, and may result in p upillary distortion. Preexisting scleral scars may predispose to scleral da mage following TCDLC. We discuss a simple strategy to avoid this complicati on of TCDLC.