Effect of optic material and haptic design on anterior capsule opacification and capsulorrhexis contraction

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.

Exploring anterion capsular contraction syndrome in cataract surgery: insights into pathogenesis, clinical course, influencing factors, and intervention approaches

Anterior capsular contraction syndrome (ACCS) is a challenging complication that can occur following phacoemulsification cataract surgery. Characterized by capsular bag wrinkling, intraocular lens (IOL) decentration and tilt, ACCS can have negative effects on visual outcomes and patient satisfaction. This review aims to investigate the pathogenesis, clinical course, influencing factors, and intervention approaches for ACCS after cataract surgery. By understanding the underlying mechanisms and identifying factors that contribute to ACCS, surgeons can enhance their ability to predict and manage this complication. Various intervention strategies are discussed, highlighting their importance in reducing complications and improving surgical outcomes. However, further research is needed to determine optimal prevention and management strategies through long-term follow-up and comparative analyses. Advancements in this field will ultimately lead to improved visual outcomes and optimized cataract surgery for patients.

ZEPTO-assisted pseudophakic capsulotomy: Precision pulse technology for management of capsular contraction syndrome

We describe a novel technique that uses precision pulse capsulotomy (PPC) to perform a secondary capsulotomy for the management of anterior capsule contraction syndrome (ACCS), a condition that comprises a late complication after cataract surgery and intraocular lens (IOL) implantation. Micropulse secondary capsulotomy offers a controlled and safe approach for patients with severe anterior capsule contraction syndrome and may be considered as an alternative surgical technique.

Surgical approach for management of complete anterior capsular contraction syndrome

Anterior capsular contraction syndrome is an uncommon but well-known complication associated with continuous curvilinear capsulorhexis performed during cataract surgery. It remains asymptomatic unless the constriction progresses to involve the visual axis or causes late intraocular lens-related complications. A male patient in his 50s presented with severely decreased vision in his right eye 2 years after uneventful cataract surgery. Slit-lamp biomicroscopy revealed capsular phimosis and a dense, central, fibrous plaque with total occlusion of the anterior capsulorhexis opening. Neodymium-doped yttrium aluminium garnet laser anterior capsulotomy and vitrectorhexis were attempted, but proved ineffective. Surgical excision with manual cutting of the fibrotic membrane was performed, successfully clearing the visual axis and restoring vision.

Effects of intraocular lens anterior edge design on anterior capsule morphology changes following femtosecond laser-assisted capsulotomy

PURPOSE

To compare morphological changes in the anterior capsule of two intraocular lenses (IOLs) with different anterior edge designs 6 months after femtosecond laser-assisted capsulotomy surgery (FLACs).

METHODS

This study included 168 eyes from168 patients undergoing FLACs. Group A included 74 eyes from 74 patients who had an Acrysof IQ Restor SN6AD3 IOL implantation with a flat anterior edge and Group B included 94 eyes of 94 patients with a TECNIS Multifocal ZMB00 IOL implantation and a "peak-like" anterior edge. All patients were followed up for 6 months. We assessed anterior capsule morphological changes including variation of anterior opening diameters and lens epithelial cell (LEC) proliferation in four directions, variation of anterior opening area, and the level of anterior capsule opacification (ACO).

RESULTS

Variation of anterior opening diameters in 4 directions were significantly lower in Group B (P < 0.05). Obvious shrinkage ratio of anterior opening diameters and contraction of anterior opening area (P < 0.05) appeared in Group A. LEC proliferation was along the "peak" in Group B, while it spread to the edge of anterior capsule in Group A. ACO grades 6 months after operation in Groups A and B were as follows: grade I in 28.38% and 82.98% of eyes, grade II in 51.35% and 17.02% of eyes, and grade III in 20.27% and 0% of eyes, respectively.

CONCLUSIONS

These findings suggest that a "peak-like" IOL anterior edge design played an important role in maintaining the morphology of anterior capsule in the early postoperative stage.

Posterior Capsule Opacification after Cataract Surgery via Implantation with Hydrophobic Acrylic Lens Compared with Silicone Intraocular Lens: A Systematic Review and Meta-Analysis

Hydrophobic acrylic intraocular lens (IOL) is the most popular material in cataract surgery. Posterior capsule opacification (PCO) is a long-term complication of cataract surgery. It can impair vision and adversely affect the prognosis of IOL delamination. The objective of this study was to perform a systematic review and meta-analysis to provide an updated evaluation of long-term complications and visual function after implantation with hydrophobic acrylic and silicone intraocular lenses. PubMed, Embase, and Cochrane Library were searched from January 2000 until March 2021. Randomized controlled trials (RCTs) and retrospective studies were finally included. The main outcomes were PCO value and neodymium-doped yttrium aluminum garnet (Nd : YAG) capsulotomy rate. Subgroup analysis was performed to compare hydrophobic acrylic and silicone IOLs during the follow-up period. Sensitivity analysis was also performed. The meta-analysis included a total of 17 studies. When the follow-up period was considered, the results of the analysis revealed higher PCO value (Group 3: standardized mean difference (SMD), −0.59; 95% confidence interval (CI), −0.90 to −0.28) and Nd : YAG capsulotomy rate (Group 3: risk ratio (RR), 0.60; 95% CI, 0.40–0.89) for hydrophobic acrylic IOLs than silicone IOLs during a long-term (≥6 years) follow-up. In conclusion, both the PCO value and the Nd : YAG capsulotomy rates were higher in hydrophobic acrylic IOLs group than the silicone IOLs group at long-term use (more than 6 years) after implantation.

Comparison Study of Anterior Capsule Contraction of Hydrophilic and Hydrophobic Intraocular Lenses Under the Same Size Capsulotomy

Purpose

To compare anterior capsule contraction of two kinds of hydrophilic and hydrophobic acrylic intraocular lenses (IOLs) under the same size capsulotomy with femtosecond laser-assisted cataract surgery (FLACS).

Methods

A total of 320 eyes in 320 patients who underwent FLACS were included. The patients were scheduled to have hydrophilic acrylic IOLs (MI60, 509M) and hydrophobic acrylic IOLs (iSert250, ZCB00) implanted. Visual acuity and anterior segment photography using a slit lamp microscope were performed at postoperative one week, one month, three months, and one year.

Results

The contraction of the anterior capsule opening area (mm²) and circumference (mm) in the hydrophilic group were larger than that of the hydrophobic group from postoperative one week to one year (P < 0.001, P < 0.001, respectively). The postoperative contraction of the capsule opening area in MI60 was larger than in 509M (P < 0.001) and larger in 509M than in iSert250 and ZCB00 (P = 0.008, P = 0.019, respectively), but no difference was observed between iSert250 and ZCB00 (P = 0.867). During postoperative one to three months, all groups had the maximum capsule contraction (P < 0.001).

Conclusions

Under the same size capsulotomy with FLACS, the postoperative anterior capsule contraction induced by hydrophobic IOLs was less than that induced by hydrophilic IOLs. Among the four IOLs, the capsule contraction was largest in MI60, followed by 509M, and least in iSert250 and ZCB00, which was time-dependent.

Translational Relevance

Our findings implied that patients with a high risk of ACC should choose hydrophobic IOLs, as well as nonsteroidal anti-inflammatory drugs may be used for a longer period in patients with high risk of capsule contraction syndrome.

Case series: "Double arch" changes caused by capsule contraction syndrome after cataract surgery in highly myopic eyes

BACKGROUND

Capsule contraction syndrome (CCS) after cataract surgery causes intraocular lens (IOL) haptic flexion and IOL optic displacement in most former reports. However, there are few reports on CCS-induced deformation of the IOL optic. We report two cases of CCS after cataract surgery in highly myopic eyes and describe a previously unreported "double arch" complication.

CASE PRESENTATION

Two patients with history of high myopia had cataract surgery with hydrophilic acrylic plate haptic IOLs implanted in their eyes. CCS with arch shape deformation of the pupil as well as the optic of the IOL were noticed in both cases after three months, which induced refractive changes and corrected distance visual acuity (CDVA) deterioration. Visual acuity of the patients was restored by replacing the IOL from the capsular bag to the ciliary sulcus and the following neodymium: YAG (Nd:YAG) laser capsulotomy. We propose that such "double arch" change brought by CCS is related to the plate-haptic design of the IOL and the incomplete overlap between the capsular opening and the IOL optic.

CONCLUSIONS

We recommend careful IOL selection and proper capsulorhexis in patients with high myopia or with other risk factors of CCS. Early diagnosis and timely treatment of CCS are critical to prevent visual symptoms and further ocular complications.

Effect of manual capsulorhexis size and position on intraocular lens tilt, centration, and axial position

PURPOSE

To evaluate the influence of a manual capsulorhexis size, shape, and position on postoperative axial position, tilt, and centration of intraocular lenses (IOLs).

SETTING

Hanusch Hospital, Vienna, Austria.

DESIGN

Prospective cases series.

METHODS

Patients had cataract surgery and had follow-ups 1 hour and 3 months after surgery. Postoperatively, patients were divided into 3 groups according to the capsulorhexis shape and size as follows: control, symmetrical capsulorhexis between 4.5 mm and 5.5 mm; small group, capsulorhexis smaller than 4.5 mm; and eccentric, all other capsulorhexes. At both follow-ups, a retroillumination image, partial coherence interferometry measurements, and Purkinje meter measurements were performed.

RESULTS

This study comprised 255 eyes. The mean postoperative absolute anterior chamber depth shift in the control, eccentric capsulorhexis, and small capsulorhexis groups was 0.31 mm ± 0.27 (SD), 0.36 ± 0.24 mm, and 0.26 ± 0.24 mm, respectively (P = .419). The mean tilt in the control, eccentric capsulorhexis, and small capsulorhexis groups was 4.08 ± 2.13 degrees, 3.66 ± 2.04 degrees, and 2.82 ± 1.67 degrees, respectively (P = .370), and the mean decentration was 0.38 ± 0.23 mm, 0.40 ± 0.21 mm, and 0.17 ± 0.08 mm, respectively (P = .027).

CONCLUSIONS

Capsulorhexis size and shape had little effect on the capsular bag performance of modern IOLs. Only eyes with a severely malformed capsulorhexis had a slightly decentered IOL.

Capsular fibrosis: a review of prevention methods and management

Opacification of the posterior capsule caused by residual lens epithelial cells (LEC) is still the most frequent long-term complication of cataract surgery. Beside the opacification of the visual axis with posterior capsule opacification (PCO), resulting in a decrease in visual function, fibrotic changes may also have a mechanical effect on intraocular lens (IOL) position such as axial shift, decentration, tilt and capsule striae. In this article, two types of capsular fibrosis are explored, on the one hand the anterior capsule fibrosis and on the other hand PCO. Results from clinical trials concerning their causes, natural course, incidence, influencing factors and possible methods of prophylaxis are presented.

Evaluation of anterior capsular contraction syndrome after cataract surgery with commonly used intraocular lenses

Purpose

The purpose of this study was to compare the incidence of anterior capsular contraction syndrome (ACCS) in cataract patients after implantation with one of two most commonly used hydrophobic acrylic lenses.

Setting

This study included patients from Loma Linda University, Loma Linda, CA, USA.

Design

This study is a retrospective chart review.

Methods

In this study, 1,047 eyes of 811 patients with and without known ACCS risk factors who underwent successful phacoemulsification and intraocular lens (IOL) implantation were included. Eyes that sustained intraoperative capsular tears and patients with a postoperative follow-up of <1 month were excluded. Each patient underwent surgery by the same surgeon receiving either the SN60WF IOL or the ZCB00 IOL. The duration of postoperative follow-up along with the presence of ACCS and the dimensions of the anterior capsule opening in these cases were recorded. The incidence of ACCS between the two lenses was compared.

Results

ACCS was significantly (P=0.045) less frequent in those patients who received the ZCB00 lens compared to those who received the SN60WF lens, despite a significantly greater (P<0.0001) number of patients with ACCS risk factors in the ZCB00 cohort.

Conclusion

In a direct comparison of the ZCB00 and SN60WF IOLs, a lower incidence of ACCS was found with ZCB00 IOL.

Comparing capsular bag performance of a hydrophilic and a hydrophobic intraocular lens: A randomised two-centre study

Purpose:

To evaluate the capsular bag performance and posterior capsule opacification development of two intraocular lenses differing in material and design.

Methods:

This study included patients who were scheduled for cataract surgery and compared a hydrophilic intraocular lens (Super flex® intraocular lens; Rayner Surgical, Worthing, UK) with a hydrophobic intraocular lens (AcrySof® SA60AT; Alcon, Fort Worth, TX, USA). Follow-ups were performed 1 month and 2 years after cataract surgery, including a slit lamp examination and retroillumination images.

Results:

In total, 80 eyes of 80 patients were recruited. At the 1-month follow-up, 6 of 39 cases had a gap between the posterior lens capsule and intraocular lens (1 case in the hydrophilic intraocular lens group and 5 cases in the hydrophobic intraocular lens group; p = 0.348). Objective and subjective posterior capsule opacification scoring showed no statistically significant difference between both groups (p = 0.123).

Conclusion:

Both intraocular lens showed a good capsular bag performance and a relatively low posterior capsule opacification development within the first 2 years after surgery.

Effect of number and position of intraocular lens haptics on anterior capsule contraction: a randomized, prospective trial

BACKGROUND

The present study aimed to evaluate the degree of anterior capsule contraction (capsulorhexis contraction) with three different single-piece, hydrophilic acrylic intraocular lenses (IOLs).

METHODS

Patients were prospectively randomized to be implanted with one of three types of IOLs during cataract surgery: the Ophtec Precizon (IOL A), the Lucid Korea Microflex (IOL B), and the Carl Zeiss Asphina (IOL C). One week, 2 weeks, and 6 months after surgery, the area of the anterior capsule opening was measured using digital retro-illumination images after dilation of the pupil. The data were then evaluated using POCOman software.

RESULTS

The study included 236 eyes of 202 patients. The area of the anterior capsule opening reduced by 3.53 ± 3.31 mm (17.06% ± 15.99%) between 1 week and 2 months post-operatively in the IOL A group, by 0.62 ± 1.32 mm (2.87% ± 6.03%) in the IOL B group, and by 1.09 ± 1.53 mm (4.72% ± 6.10%) in the IOL C group. The IOL B group showed minimal anterior capsule contraction 2 months after surgery (p < 0.001).

CONCLUSIONS

IOLs with a four-plate haptic design (IOL B) showed more anterior capsular stability than those with a two-loop plate haptic (IOL A) or two-plate haptic (IOL C) design. The number and position of haptics in a capsular bag may affect anterior capsule contraction. We assume that supporting the zonules evenly may play a role in anterior capsular stability.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN76566080 , Retrospectively registered (Date of registration: 14 Feb 2018).

Biomaterial Influence on Intraocular Lens Performance: An Overview

There is strong evidence that the IOL material is the factor having the greatest impact on posterior capsule opacification (PCO), anterior capsule opacification (ACO) development, and glistening formation after cataract surgery, even though there are other IOL features—such as haptic material and design and edge and optic design—that also have some influence. We reviewed the published literature describing the adverse events that are mainly related to the intraocular lens (IOL) material, such as PCO, ACO, and the subsequent capsule contraction, as well as glistening formation. The adverse events presented in this overview are the most common ones in clinical practice, and therefore, they are generally included in the clinical protocols for IOL evaluation.

Biocompatibility of Intraocular Lenses

The performance of an intraocular lens is determined by several factors such as the surgical technique, surgical complications, intraocular lens biomaterial and design, and host reaction to the lens. The factor indicating the biocompatibility of an intraocular lens is the behavior of inflammatory and lens epithelial cells. Hence, the biocompatibility of intraocular lens materials is assessed in terms of uveal biocompatibility, based on the inflammatory foreign-body reaction of the eye against the implant, and in terms of capsular biocompatibility, determined by the relationship of the intraocular lens with residual lens epithelial cells within the capsular bag. Insufficient biocompatibility of intraocular lens materials may result in different clinical entities such as anterior capsule opacification, posterior capsule opacification, and lens epithelial cell ongrowth. Intraocular lenses are increasingly implanted much earlier in life in cases such as refractive lens exchange or pediatric intraocular lens implantation after congenital cataract surgery, and these lenses are expected to exhibit maximum performance for many decades. The materials used in intraocular lens manufacture should, therefore, ensure long-term uveal and capsular biocompatibility. In this article, we review the currently available materials used in the manufacture of intraocular lenses, especially with regard to their uveal and capsular biocompatibility, and discuss efforts to improve the biocompatibility of intraocular lenses.

Straylight before and after phacoemulsification in eyes with preoperative corrected distance visual acuity better than 0.1 logMAR

PURPOSE

To report the outcomes of changes in straylight before and after phacoemulsification in eyes with preoperative corrected distance visual acuity (CDVA) better than 0.1 logMAR.

SETTING

Private refractive surgery clinic, Driebergen, the Netherlands.

DESIGN

Cohort study.

METHODS

Standard phacoemulsification with implantation of a monofocal or multifocal intraocular lens (IOL) was performed. Preoperative and 3-month postoperative straylight values, CDVA, and refractive error were compared.

RESULTS

The study enrolled 160 eyes (89 patients). The mean CDVA was 0.02 ± 0.05 logMAR (range -0.1 to 0.1 logMAR) preoperatively and 0.00 ± 0.04 logMAR (range -0.1 to 0.2 logMAR) postoperatively. The mean preoperative straylight was 1.21 ± 0.20 log(s) (range 0.80 to 1.74 log[s]) and 1.11 ± 1.16 log(s) (range 0.76 to 1.63 log[s]), respectively; the improvement was statistically significant. There was a correlation between high preoperative straylight values and postoperative improvement in straylight values.

CONCLUSIONS

In eyes with relatively good CDVA of 0.1 logMAR or better (decimal 0.8 or better; Snellen 20/25 or better), straylight improved by 0.10 log(s) after cataract surgery. A subgroup of 44 eyes had an improvement of more than 0.20 log(s), which is comparable to a 2-line improvement on the vision chart.

Posterior capsule opacification in silicone and hydrophobic acrylic intraocular lenses with sharp-edge optics six years after surgery

PURPOSE

To compare posterior capsule opacification (PCO) between 2 three-piece intraocular lenses (IOLs) both with sharp-optic edges and open loop haptics, one made of silicone and the other made of hydrophobic acrylate, 6 years after surgery.

DESIGN

Randomized, controlled, patient- and examiner-masked trial with intra-patient comparison.

METHODS

One hundred and six eyes in 53 patients were included initially. Forty-four eyes of 22 patients with age-related bilateral cataract were available for the 6 years follow-up. Each patient had standard cataract surgery and randomly received a silicone (CeeOn 911A; AMO, Santa Ana, California, USA) or hydrophobic acrylic (AcrySof MA60BM; Alcon, Fort Worth, Texas, USA) IOL in the first eye, the other type of IOL in the fellow eye. Follow-up examinations were at 1, 3, and 6 years after surgery. The intensity of posterior capsule opacification (PCO) was assessed using digital retro-illuminated photos and the "automated quantification of after-cataract" (AQUA) software. Neodymium-yttrium-aluminum-garnet-laser capsulotomies (YAG-LC) performed were noted.

RESULTS

Six years after surgery, the AQUA scores were 2.3 +/- 1.4 for the silicone and 3.8 +/- 2.0 for the acrylic IOLs (P = .0016). The acrylic IOL eyes also had a significant increase in AQUA score from the 3-year to the 6-year follow-up. YAG-LC were performed in 2 silicone and 6 acrylic IOLs (P = .01).

CONCLUSIONS

An angulated three-piece hydrophobic acrylic IOL had more PCO 6 years after surgery than a silicone IOL of otherwise similar design. Apart from an optic material effect, differences in haptic design and the degree of optic edge sharpness may play a role.

Biocompatibility of intraocular lens materials

PURPOSE OF REVIEW

To provide an update on currently available materials used in the manufacture of intraocular lenses, as well as new materials under development, especially with regard to their uveal and capsular biocompatibility.

RECENT FINDINGS

The biocompatibility of intraocular lens materials should be assessed in terms of uveal biocompatibility, related to the inflammatory foreign-body reaction of the eye against the implant, as well as in terms of capsular biocompatibility, determined by the relationship of the intraocular lens with remaining lens epithelial cells within the capsular bag. This situation may result in different entities, e.g. anterior capsule opacification, interlenticular opacification (between piggyback intraocular lenses), posterior capsule opacification and lens epithelial cell ongrowth. Reports on intraocular lens opacification suggest that the potential to calcify should also be taken into consideration when evaluating the long-term biocompatibility of a new material.

SUMMARY

Intraocular lenses are being progressively implanted in much earlier stages of life (refractive lens exchange, pediatric implantation) and are expected to remain in the intraocular environment for many decades. Materials used in intraocular lens manufacture should, therefore, insure long-term uveal and capsular biocompatibility, as well as ultimate transparency after implantation.

Capsule contraction syndrome in eight cases of hydrophobic one-piece intraocular lens implantation

PURPOSE

The combination of anterior capsule opacification (ACO) with capsulorrhexis phimosis and intraocular lens (IOL) decentration characterises the capsule contraction syndrome (CCS). Eight cases of ACO complicated with capsule phimosis are described.

METHODS

In this study, 231 patients who underwent cataract extraction using phacoemulsification from September 2005 to May 2006 were included. An acrylic one-piece IOL was implanted with the use of the injector supplied by the manufacturer through a 2.75 mm incision. A thorough pre- and post-operative examination (visual acuity measurement, corneal curvature measurement, applanation tonometry, fundus examination) was performed for each patient.

RESULTS

In eight of 243 eyes of 231 patients, anterior capsule opacification with capsulorrhexis phimosis and IOL decentration was observed two to four months post-operatively. In all eight cases, the haptic implanted inferiorly was observed to be mounted on the IOL optic.

CONCLUSIONS

The combination of IOL memory loss in addition to ACO, capsulorrhexis phimosis and decentration can be a cause of the CCS, an observation that has not been reported previously.