1. A case of hypermature cataract formation following implantation of a posterior chamber phakic intraocular lens with a central hole The Catholic University of Korea, Seoul St. Mary’s Hospital, Seoul, Korea So-Hyang Chung The author has no financial interests to disclose.

2. A 29-year-old man showed an anterior subcapsular cataract and lens swelling in the left eye following implantation of an implantable collamer lens (ICL) with an hole 4 months ago at other eye clinic. According to his medical record, ICLs (12.6 mm) was inserted at superior corneal incision and rotated to horizontal axis. Uncorrected distance visual acuity (UDVA) in both eyes was 20/20 on postoperative day 7, and there was no intraoperative surgical complication.

3. Manifest refraction -1.75Ds : -0.50Dc Ax 155 (0.4) (OS) IOP 15 mmHg at 2:00 PM (OS) Anterior chamber depth 2 CT at center, <1/4 CT at periphery (OS) Vaulting of ICL ½ CT, Inferonasal decentered hole (OS) Lens Vertically positioned ICL (OS) Moderate cortical opacity (OS) White to white (WTW): 12 mm (OU) Size of implanted ICLs: 12.6mm (OU) On first examination

4. Vision: Hand motion (OS) Lens Swelling (OS) Abnormal aggravation to hypermature cataract (OS) Anterior chamber: cells 2+ ICL removal and Cataract extaction Multifocal IOL implantation (OS) POD 1 Day Far vision: 20/30 Intermediate vision: 20/40 Near vison: 20/20 After 1 month after 1 st visit

5. IL-6 : 69.6 pg/mL (Normal: 0~46 pg/mL) The whitish infiltrates on the explanted ICL surface by slit-lamp microscopy Pro-inflammatory cytokines in anterior chamber ELISA

6. VA OD 1.0 Vault 500um Rotated to vertical ICL position Decentered hole No cataract

7. Cataract formation after conventional ICL implantation  In the present literature review comprising 2592 eyes, the occurrence of cataract formation with the latest ICL models was 5.2%. 1  Most were reported as nonprogressive or slowly progressive and asymptomatic.  However, in 30.1 % of eyes, the opacity became clinically significant and cataract surgery was performed in 27.9% of eyes.  Previous studies showed that hole-ICL is associated with low postoperative complication rates compared to conventional ICL due to the possible flow of the aqueous humor through the hole. 2-4 1. Fernandes P, Gonzalez-Meijome JM, Madrid-Costa D, Ferrer-Blasco T, Jorge J, Montes-Mico R. Implantable collamer posterior chamber intraocular lenses: a review of potential complications. J Refract Surg. 2011;27:765-776. 2. Shimizu K, Kamiya K, Igarashi A, Shiratani T. Early clinical outcomes of implantation of posterior chamber phakic intraocular lens with a central hole (Hole ICL) for moderate to high myopia. Br J Ophthalmol. 2012;96:409-412. 3. Kamiya K, Shimizu K, Saito A, Igarashi A, Kobashi H. Comparison of optical quality and intraocular scattering after posterior chamber phakic intraocular lens with and without a central hole (Hole ICL and Conventional ICL) implantation using the double-pass instrument. PLoS One. 2013;8:e66846. 4. Shimizu K, Kamiya K, Igarashi A, Shiratani T. Intraindividual comparison of visual performance after posterior chamber phakic intraocular lens with and without a central hole implantation for moderate to high myopia. Am J Ophthalmol. 2012;154:486-494.e481.

8.  A low vault and decentration of an hole  A low valut might lead to disturbances in the aqueous flow, interfering with lens nutrition and causing metabolic disturbances to the crystalline lens.  The rapid flow of hole 5 might cause rapid progression of cataract especially in low vaulting cases.  Decentered hole might prevent an adequate circulation of the aqueous humor, which causes increase of pro- inflammatory cytokine IL-6 in the anterior chamber and whitish infiltration on the ICL surface. Possible reason of rapid progression of cataract in the eye with hole-ICL 5. Kawamorita T, Uozato H, Shimizu K. Fluid dynamics simulation of aqueous humour in a posterior-chamber phakic intraocular lens with a central perforation. Graefes Arch Clin Exp Ophthalmol. 2012;250:935-939

9.  This case demonstrates the rapid progression of the cataract in a patient with the hole-ICL. Although a central hole of ICL was designed to improve the aqueous humor circulation, low vaulting, decentrated hole, and rapid flow of hole may induce the rapid progression of cataract. Surgeons might consider faster removal of the hole-ICL in patients who developed cataract compared to the patients with conventional ICL.