Conjunctival Hypertrophic Scar Following Cryotherapy for Retinopathy of Prematurity
A 6-year-old boy presented with lateral canthal deformity in both eyes, which developed 6 years ago. The patient was born at 27 weeks gestation. He had received cryotherapy in both eyes for ROP at 6 weeks. One month after cryotherapy, he developed symblepharon in both eyes, and underwent left symblepharon lysis at another hospital at 1 year of age.\nOn ocular examination, visual acuity was 20 / 200 OU. Ocular motility examination revealed 40 prism diopters of exotropia by the Krimsky method and restriction of adduction OS. Both eyes showed seesaw nystagmus. The anterior segment examination revealed lateral canthal deformity and conjunctival hypertrophy with symblepharon in both eyes, which was more severe in the left eye (). Fundus examination showed pre-retinal membrane in the right eye; however, we were not able to observe the fundus of the left eye due to a small pupil with posterior synechia.\nAn excisional biopsy, lateral canthoplasty, and symblepharon lysis with conjunctival autograft from the contralateral eye were performed in the left eye. Conjunctival scar tissue was excised and adhesion surrounding the lateral rectus muscle was completely relieved. To cover the bare sclera, a conjunctival graft was harvested from 3 clock hours of inferior bulbar conjunctiva of the contralateral eye. The conjunctival graft was sutured with surrounding conjunctiva using interrupted 7-0 Vicryl sutures. In addition, lateral canthoplasty using fornix forming sutures with 4-0 chromic catgut was also performed to reconstruct the lateral canthus.\nHistopathologic examination revealed diffuse proliferation and infiltration of the collagenous tissue. These findings were consistent with a hypertrophic scar of conjunctival tissue (). Postoperative visual acuity was 20 / 100 OU. Exotropia was reduced to 20 prism diopters by the Krimsky method with full ductions and versions OS. There has been no evidence of recurrence over a 1-year follow-up period ().