Reverse pupillary block after implantation of a scleral-sutured posterior chamber intraocular lens: a retrospective, open study

Background: To report the clinical features of patients with reverse pupillary block (RPB) after scleral-sutured posterior chamber intraocular lens (PC IOL) implantation and biometric changes after laser peripheral iridotomy (LPI). Methods: Eight patients attending our hospital's ophthalmology outpatient clinic, who developed RPB after implantation of a scleral-sutured PC IOL due to subluxation of the crystalline lens or IOL, were investigated in this retrospective, observational study. Results: Preoperative evaluations showed angle pigmentation in all cases and iridodonesis in 2 cases. Two subjects had used an alpha(1A)-adrenoceptor antagonist for benign prostatic hyperplasia. Pars plana or anterior partial vitrectomy was performed in all cases. All eyes showed an extremely deep anterior chamber, a concave iris configuration, and contact between the IOL optic and the iris at the pupillary margin. Pupil capture was detected in 2 cases. The mean (+/- SD) anterior chamber angle (ACA) was 89.91 +/- 10.06(omicron), and the anterior chamber depth (ACD) was 4.42 +/- 0.16 mm before LPI. After LPI, the iris immediately became flat with a decreased ACA (51.70 +/- 2.59(omicron); P = 0.018) and ACD (4.14 +/- 0.15 mm; P = 0.012). After LPI, the intraocular pressure decreased from 19.75 +/- 3.77 mmHg to 15.63 +/- 4.30 mmHg (P = 0.011), and the spherical equivalent decreased from -0.643 +/- 0.385 D to -0.875 +/- 0.505 D (P = 0.016). Conclusion: Concomitant vitrectomy, angle pigmentation, and iridodonesis may be risk factors for RPB after scleral-sutured PC IOL implantation. LPI is effective for relieving the RPB.