Implantation of Capsular Tension Ring in Primary Angle Closure Patients With Zonular Laxity or Dialysis

Patients with PACD who are scheduled to have phacoemulsification and IOL implantation combined with goniosynechialysis are recruited. All recruited patients attended comprehensive eye examinations and interviews. Past history of ocular and systemic diseases, family and personal history, history of ocular trauma and surgery were interviewed. And the patients underwent ophthalmic examinations including visual acuity tests (presenting visual acuity \[PVA\] and best-corrected visual acuity \[BCVA\]), subjective refraction, intraocular pressure (IOP) measurements, slit-lamp examination, fundus photography, gonioscopy, ocular biometry using IOL Master 700, ultrasound biomicroscopy, anterior segment optical coherence tomography (ASOCT) imaging. All patients provide informed consent for inclusion in the study. All surgery procedures were performed by the same surgeons (CYQ) using the same standard operation procedure. All patients use the same type of foldable IOL calculated using SRK/T formula. During the surgery, patients with wrinkling of the anterior capsule (multiple sinusoidal folds were formed) during continuous curvilineal capsulorhexis (CCC) at the needle or forceps tip but without infolding of peripheral capsule or visualisation of the capsular equator during the cortical or nuclear removal, or, wrinkling of the anterior capsule during CCC with infolding of peripheral capsule and visualisation of the capsular equator ≤ 4 clocks of range during the cortical or nuclear removal, were finally included in the study and randomly assigned (using a random-number table generated by SAS) with equal probability to either CTR group (with CTR implantation during the surgery) and control group (without CTR implantation during the surgery). All patients included in the CTR group use the same type of CTR. The investigators recorded the complications during the surgery including vitreous prolapse, hyphema, vitreous hemorrhage, damage of iris and lens capsule, et al. Postoperatively, all patients received similar routine medication comprising topical prednisolone acetate (six times a day for 1 week and tapered down by 1 time every week), topical levofloxacin hydrochloride (four times a day for 1 month), and Tobramycin and Dexamethasone Eye Ointment (1 time every night for 1 month). Postoperative examinations were performed at 1 day, 1 week, 1 months, 3 months, 6 months and 12 months. During the follow-up visits, a complete ophthalmic examination was performed including PVA, BCVA, subjective refraction, non-contact IOP measurement, slit-lamp examination, slit-lamp photography after pupil dilation, ASOCT, gonioscopy, and fundus imaging.