Explantation of Implantable Collamer Lenses due to high intraocular pressure in a highly hyperopic patient: a case report

Implantable Collamer Lens (ICL) implantation is an effective treatment for correcting high hyperopia. However, late anterior segment complications remain insufficiently characterized. The simultaneous occurrence of angle narrowing, pigment dispersion, and intraocular pressure (IOP) elevation nearly two decades after implantation of a non-central-port ICL is exceptionally rare. This case illustrates the diagnostic and surgical challenges of late-onset angle narrowing in hyperopic eyes and outlines strategies to minimize iris injury during ICL explantation. A 38-year-old woman presented with progressive bilateral elevation of IOP occurring 15 years after implantation of non-central-port ICLs for high hyperopia. Slit-lamp examination revealed shallow anterior chambers with patent peripheral iridotomies, narrow angles with partial peripheral anterior synechiae, and pronounced pigment deposition on the corneal endothelium, ICL surfaces, and trabecular meshwork. Sequential ICL explantation combined with cataract extraction and posterior chamber intraocular lens implantation was performed. During surgery on the left eye, mechanical iris trauma resulted in a sectoral iris defect causing monocular diplopia and photic disturbances. Despite undergoing iris repair, the patient’s photic symptoms did not improve. In the right eye, preoperative cycloplegia and intravenous mannitol deepened the anterior chamber and prevented iris injury. Postoperatively, both eyes developed a transient fibrin reaction that resolved with topical anti-inflammatory therapy. At the 6-month follow-up, IOP and visual acuity remained stable in both eyes, although mild glare sensitivity persisted. This case demonstrates that late-onset angle closure and pigment dispersion can occur after ICL implantation, particularly in highly hyperopic eyes with shallow anterior chambers. Lifelong monitoring of anterior chamber configuration and IOP is therefore essential in these patients. When IOP elevation secondary to angle closure develops, combined ICL explantation and cataract surgery can effectively restore aqueous outflow and visual function. Adequate preoperative deepening of the anterior chamber and avoidance of intraoperative iris manipulation are critical to minimize postoperative dysphotopsia and monocular diplopia.