Post-operative changes in the capsulorhexis aperture: a prospective, randomised comparison between loop and plate haptic silicone intraocular lenses

Effect of intraocular lens material and haptic design on anterior capsule contraction after cataract surgery: A systematic review and meta-analysis

PURPOSE

To compare anterior capsule contraction (ACC) after cataract surgery with implantation of intraocular lens (IOLs) of different materials and designs.

METHODS

We searched three electronic databases for relevant studies published up to January 1, 2023. Five randomized controlled trails (RCTs) and three cohort studies involving 1,221 eyes were included in quantitative synthesis. We extracted data, assessed their quality independently, and calculated standard mean difference (SMD) using a random-effects model. Six RCTs and one retrospective cohort were included in information summary.

RESULTS

The contraction of the anterior capsule opening area in the hydrophilic group was larger than that of the hydrophobic group from one month to one year postoperatively (P < 0.001 and P < 0.001, respectively). Specifically, the hydrophilic group showed greater contraction of the anterior capsule opening area at one month postoperatively (Standardized mean difference [SMD] = -0.73, 95% confidence interval [CI] = -0.93 to -0.52), three months (SMD = -1.04, 95% CI = -1.32 to -0.75), six months (SMD = -0.99, 95% CI = -1.24 to -0.74) and one year (SMD = -1.33, 95% CI = -2.50 to -0.16). As of one year postoperatively, the anterior capsular opening area showed a trend of decreasing over time in both groups (P = 0.046 and P = 0.050, respectively). In information summary, three studies indicated no relationship between haptic design and ACC, while the other four studies reported that the number and shape of haptic would affect ACC.

CONCLUSION

This meta-analysis suggested that the postoperative ACC after the implantation of hydrophobic IOLs was less than that induced by hydrophilic IOLs. Haptic design may also affect the degree of ACC.

Effect of lens epithelial cell aspiration on postoperative capsulorhexis contraction with the use of the AcrySof intraocular lens

PURPOSE

To determine whether aspiration of lens epithelial cells (LECs) from under the anterior capsule reduces postoperative contraction of the capsulorhexis aperture.

SETTING

Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, United Kingdom.

METHODS

This prospective randomized observer-masked study comprised 100 patients who had routine phacoemulsification by the same surgeon at a district general hospital in the United Kingdom. The postoperative changes in capsulorhexis apertures and anterior capsule opacification (ACO) between Group A (aspiration of LECs) and Group B (control) were compared. Digital retroillumination images of the capsulorhexis aperture were taken 1 week and 3 months postoperatively. The area of capsulorhexis aperture was determined with computer software, and capsule opacification was graded subjectively.

RESULTS

Three months postoperatively, the mean decrease in capsulorhexis aperture was 1.9% in Group A and 5.6% in Group B (P = .02). The ACO at 3 months was grade 2 in 44% of eyes in Group A and in 61% in Group B (P = .13).

CONCLUSION

Aspiration of LECs from the anterior capsule was a safe procedure that reduced capsulorhexis aperture contraction 3 months after cataract surgery.

Anterior capsule opacification: correlation of pathologic findings with clinical sequelae

OBJECTIVE

To evaluate the degree of anterior capsule opacification (ACO) in human eyes obtained postmortem containing various rigid and foldable posterior chamber intraocular lens (PC-IOL) designs and compare the findings with clinical sequelae of capsular shrinkage.

DESIGN

Comparative autopsy tissue study with clinicopathologic correlations.

MATERIALS

Three hundred formalin-fixed human eyes containing the following PC-IOL styles were analyzed: (1) one-piece polymethyl methacrylate (PMMA) optic-PMMA haptic (n = 50), one-piece silicone-plate IOL, with large (2) or small (3) fixation holes (n = 35), (4) three-piece PMMA optic-Prolene haptic (n = 50), (5) three-piece acrylic optic-PMMA haptic (n = 55), three-piece silicone optic with PMMA (6) or polyimide (7) haptics (n = 30), and (8) three-piece silicone optic-Prolene haptic (n = 80) lenses.

TESTING

The eyes were sectioned in the equatorial plane for gross examination of the capsular bag from a posterior view. The cornea and iris were then excised for evaluation from an anterior view.

MAIN OUTCOME MEASURES

ACO was scored in each eye from 0 to IV, according to the degree/area of capsule opacification. Capsulorrhexis size and IOL decentration were measured with calipers.

RESULTS

The overall differences among the IOL groups regarding the three parameters were significant (ACO score: P < 0.001; capsulorrhexis diameter: P = 0.036; IOL decentration: P = 0.012). Mean ACO scores were highest with the large- and small-hole one-piece silicone-plate lenses (2.543 +/- 0.950) and lowest with the three-piece acrylic optic-PMMA haptic lenses (0.600 +/- 0.710). Of 10 cases of capsulorrhexis phimosis observed in the study, 7 cases were associated with three-piece silicone optic-Prolene haptic lenses, which also presented the highest mean decentration (0.375 +/- 0.601 mm).

CONCLUSIONS

Our results confirm previous histopathologic observations that the rate of ACO is the lowest with acrylic lenses and higher with plate-haptic silicone IOLs. Nevertheless, clinical sequelae of capsular shrinkage are also very important with three-piece silicone optic-Prolene haptic designs. Thus, IOL material and design are significant factors in the development of ACO, but they ultimately also influence the clinical presentation of capsular shrinkage.

Bimanual Sinskey hook technique to enlarge a preexisting capsulorhexis

We describe a technique of enlarging a small primary capsulorhexis. Two Sinskey hooks are introduced through the side ports. One hook is placed above the anterior capsulorhexis margin with its tip pointing down, and the other is placed beneath the anterior capsulorhexis margin with its tip pointing up. A small nick is made between the tips of the 2 hooks, and the capsulorhexis is extended with a Utrata capsulorhexis forceps. This technique does not require additional instrumentation, impart zonular stress, or disturb wound architecture or integrity.