Nd:YAG laser treatment for pupillary block secondary to toxic anterior segment syndrome after hole implantable collamer lens surgery.

Purpose: To report the clinical course of pupillary block by fibrin in the central hole of an implantable collamer lens (ICL). Observations: A 24 year old male with high myopia and astigmatism underwent EVO ICL (V5; STAAR Surgical, Monrovia, CA) implantation. The surgery was completed without any complications. The following day, the patient complained of blurry vision in the right eye and headache. The decimal uncorrected distance visual acuity was 1.5 in both eyes. Slit-lamp examination of the right eye revealed fibrin in the central hole of the ICL with a few cells in the anterior chamber. The intraocular pressure (IOP) and vault were increased to 33 mmHg and 1396 μm, respectively. A single shot of the Nd:YAG laser swept away the fibrin, and the reopening of the central hole was confirmed through the aqueous humor flow. The pupillary block was completely relieved 30 min later and the IOP and vault recovered to the normal range. One week postoperatively, the inflammatory reaction disappeared with topical eye drops including steroids. The uncorrected distance visual acuity was 1.5 in both eyes one year postoperatively. Ophthalmic examinations revealed unremarkable findings. We diagnosed the cause of the inflammatory reaction in the right eye as TASS because of the lack of severe pain in the eye, early occurrence, and favorable response to steroid therapy. Conclusions and importance: Pupillary block by fibrin in the central hole may rarely occur following ICL implantation. In such cases, direct fibrin removal using Nd:YAG laser may be an effective treatment.