Iris-Claw Intraocular Lens: Anterior Chamber or Retropupillary Implantation? A Systematic Review and Meta-Analysis

Abstract

Background and Objectives: Iris-claw intraocular lens (ICIOL) could be implanted in the anterior chamber (AC) or retropupillary (RP) in eyes lacking capsular and/or zonular support. Several studies have focused on comparing the efficacy and complications of these two techniques and we designed this research to review the published literatures. Materials and Methods: Peer-reviewed studies were collected through network databases (PubMed, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov) and analyzed. The primary outcome was the standardized mean differences (SMDs) of pre- and post-operative corrected distant visual acuity (CDVA). The secondary outcome was the SMDs of pre- and post-operative intraocular pressure (IOP), endothelial cell counts (ECC), and the odds ratios (ORs) of post-operative IOP elevation and cystoid macular edema (CME). Comprehensive Meta-Analysis software was utilized to conduct statistical analysis. Results: Six studies (one randomized controlled trial and five retrospective case series) were relevant and included a total of 516 eyes (255 and 261 eyes in the AC ICIOL and RP ICIOL groups, respectively). The quantitative analysis showed no significant differences in CDVA (SMD: 0.164, 95% confidence interval (CI): −0.171 to 0.500), ECC (SMD: −0.011, 95% CI: −0.195 to 0.173), and IOP elevation events (OR: 0.797, 95% CI: 0.459 to 1.383). Lesser IOP reduction (SMD: 0.257, 95%CI: 0.023 to 0.490) and a relative increase in the incidence of CME (OR:2.315, 95% CI: 0.950 to 5.637) were observed in the AC ICIOL group compared with RP ICIOL group. Conclusions: Our meta-analysis indicated that AC and RP ICIOL seem to have equivalent visual outcomes. RP ICIOL may perform slightly better with more IOP reduction and lesser CME. More randomized controlled trials, which have higher patient participation and more outcomes are needed to confirm our conclusions.

Scleral Fixation of Carlevale Intraocular Lens: A Systematic Review And Meta-Analysis

“…Nonetheless, the rate of CME seems to be lower than that of other techniques, often higher than 5% with iris claw. 31 Moreover, conjunctival or scleral erosions were observed in two studies. 11,22 This mostly occurred after IOL implantation without scleral flap creation.…”

A meta-analysis of sutureless scleral-fixated intraocular lens versus retropupillary iris claw intraocular lens for the management of aphakia

“…IOP elevation after IOL implantation has been reported in many studies 22 , 23 , and it is also commonly caused by postoperative steroid usage, anterior chamber inflammation, and pigment dispersion. Many studies revealed transient IOP elevation after surgery and these patients were treated with medication 12 , 14 , 15 .…”

Ursachen und Management von IOL-Dislokationen

“…Verschiedene Studien berichteten, dass die präpupilläre Fixierung zur Aphakiekorrektur insbesondere bei flacher Vorderkammer zu einem Endothelzellverlust führen kann [15,16]. Ein Endothelzellverlust bei der retropupillären Fixierung ist aufgrund des Traumas im Rahmen des operativen Eingriffs beschrieben, durch die größere Entfernung vom Endothel im Vergleich zur präpupillären Fixierung ist ein chronischer Endothelschaden jedoch eher nicht zu erwarten [17,18].…”

“…Several studies have reported that prepupillary fixation for aphakic correction can lead to endothelial cell loss, especially with a flat anterior chamber [15,16]. Endothelial cell loss during retropupillary fixation has been described due to trauma during the surgical procedure; however, chronic endothelial damage is not expected [17,18] due to the greater distance from the endothelium compared with prepupillary fixation.…”