Current status of late and recurrent intraocular lens dislocation: analysis of real-world data in Japan

Characteristics of Patients with Late-onset Intraocular Lens Dislocation: A Prospective Multicenter Clinical Cohort Study in Japan

PURPOSE

To evaluate the patients' characteristics and ocular features of those who underwent surgery for late-onset intraocular lens (IOL) dislocation from 2020 to 2021 at multiple surgical centers in Japan. We also assessed the factors influencing the duration between prior IOL implantation and IOL dislocation repair as well as the factors affecting visual prognosis after IOL dislocation repair surgery.

DESIGN

A prospective multicenter clinical cohort study.

PARTICIPANTS

The study included 712 eyes of 712 patients.

METHODS

We collected data on the patients' characteristics and ocular features and performed multivariable linear regression analyses.

MAIN OUTCOME MEASURES

Factors influencing the duration between prior IOL implantation and IOL dislocation repair, as well as factors affecting visual prognosis after repair surgery.

RESULTS

The average duration between prior IOL implantation and IOL dislocation repair surgery was 131.5 ± 85.7 months (approximately 11 years). The average age of the patients at IOL dislocation repair surgery was 67.2 ± 14.2 years. Male patients (n = 529, 74.3%) were significantly younger than female patients (P = <.0001). During IOL dislocation repair surgery, the dislocated IOL was extracted in 655 (92.0%) eyes, and a secondary IOL was implanted in 555 (77.9%) eyes using the IOL haptics scleral fixation technique. Multivariable linear regression analysis demonstrated that younger age at IOL dislocation repair surgery (P = .0008), shorter axial length (P = .0004), and use of a capsular tension ring during prior IOL implantation (P = .0004) were significantly associated with shorter duration until IOL dislocation repair surgery. Furthermore, older age at repair surgery (P = .0051), worse preoperative visual acuity (P = <.0001), being female (P = .0005), and history of vitrectomy (P = .0061) were significantly associated with worse postoperative visual acuity. IOL dislocation status did not affect visual prognosis after repair surgery.

CONCLUSIONS

This study highlights significant factors that affect the duration until late-onset IOL dislocation repair surgery and postoperative visual acuity after repair surgery. While an optimal timing for IOL dislocation repair surgery has not been fully established, our study suggests that IOL dislocation status does not affect visual prognosis.

Risk and protective factors of late in-the-bag intraocular lens dislocations: systematic review

TOPIC

To identify and review published articles addressing risk and protective factors of late in-the-bag (ITB) intraocular lens (IOL) dislocations.

CLINICAL RELEVANCE

Prevention of this complication is of great importance considering the great number of cataract cases and its vision-threatening capacity.

METHODS

A structured search on PubMed (MEDLINE) using both Medical Subject Headings and key words was conducted. In addition, the reference lists of the resulting articles were screened for further publications. Articles were eligible if they included 20 or more patients. Hazard and odds ratios were analyzed if they were calculated in the original study. The relative frequency of risk factors was recorded if hazard or odds ratios were not available. The threshold for clinical significance was set at 10%. Risk-of-bias in individual studies was evaluated using the revised Cochrane risk-of-bias tool in randomized trials (RoB 2.0) and the Cochrane risk-of-bias in nonrandomized studies of intervention tool.

RESULTS

Database search identified 3474 records, and no further records were obtained from the reference lists. After exclusion of records not related to the topic, 177 articles were assessed for eligibility. Of these, 39 were considered eligible and read in full. 3 studies were prospective, while all other investigations were retrospective. In total, 18 614 cases of late ITB dislocations were analyzed across all studies. The risk of bias within studies was considerable because only 3 studies were prospective and statistical significance of risk factors was assessed in only 5 studies.

CONCLUSIONS

Typical patient age of this condition is between 70 and 85 years, and there seems to be a slight male predominance. Risk factors with a good level of evidence include preoperative trauma and zonular dehiscence, previous vitrectomy, retinitis pigmentosa, pseudoexfoliation, high myopia, glaucoma/previous glaucoma surgery, corneal endothelial damage, and uveitis. Hydrophilic, quadripode, and haptic-angulation IOLs are further risk factors. Capsular tension rings, Nd:YAG capsulotomy, 3-piece IOLs, and IOLs with large optic diameters protect from ITB dislocations. Typically, no risk factors can be identified in approximately one-fourth of patients.

Factors predicting redislocation or suture break in eyes after scleral-fixated intraocular lens

PURPOSE

To investigate predictive factors for redislocation in patients with recurrent intraocular lens (IOL) dislocation after secondary scleral-fixated IOL (SF IOL) surgery.

SETTING

2 tertiary referral hospitals.

DESIGN

Retrospective case series.

METHODS

Patients undergoing SF IOL surgery were grouped into redislocation and no-redislocation groups. Medical records of consecutive patients who underwent SF IOL surgery between June 2014 and December 2019 at 2 tertiary referral centers were reviewed. Data regarding patient demographics, treatment factors, anatomical and functional outcomes, and postoperative complications were recorded.

RESULTS

237 eyes of 225 patients (169 [75.1%] men) were included. The redislocation group was more likely to have a younger mean age at the initial SF IOL surgery (redislocation vs no-redislocation, 55.4 vs 62.0 years, respectively; P = .008), have a prior history of a previous suture break (23 eyes, 52.3% vs 1 eye, 0.5%; P < .001), and have undergone the initial SF IOL surgery using <1 mm-sized side-port incisions (17 eyes, 38.6% vs 32 eyes, 16.5%; P = .002) than was the no-redislocation group. In addition, the redislocation group had a higher occurrence of complications ( P < .001). Multivariate regression revealed that younger age, left eye involvement, aphakic status before the surgery, unremarkable primary IOL dislocation cause, need for ocular hypertension treatment and glaucoma surgery, and no large incision during the initial surgery were significantly (all P < .05) associated with redislocation.

CONCLUSIONS

Younger age, left eye involvement, postoperative complications such as ocular hypertension and glaucoma, and techniques without large incisions increase the risk of redislocation. Conversely, lower risk factors include unremarkable surgery causes and a history of aphakic conditions.

Clinical Characteristics of recurrent intraocular lens dislocation after scleral-fixated sutured intraocular lens and long-term outcomes of intraocular lens re-fixation

PURPOSE

This study aimed to investigate the clinical characteristics of patients with recurrent intraocular lens (IOL) dislocation after scleral-fixated sutured IOL implantation and evaluate the long-term outcomes of scleral re-fixation of IOL.

METHODS

The medical records of patients who underwent surgery for IOL dislocation between January 2011 and January 2021 were reviewed. The study included 164 patients (male: 131, female: 33) (176 eyes). Patient demographics, preoperative, intraoperative and postoperative data, and the ocular and systemic conditions associated with IOL re-dislocation were analyzed.

RESULTS

The study included 176 consecutive cases of scleral-fixated sutured IOL. Twenty-six eyes (14.8%) showed re-dislocation of IOL after the initial IOL scleral fixation and underwent reoperation (mean 75.5 ± 62.5 months after the first surgery); three (11.5%) of them required a third surgery. Younger adults (aged less than 40 years), and patients who underwent IOL scleral fixation in complicated cataract surgery or aphakic state had a higher risk of re-dislocation. Diabetes mellitus (DM) was the only statistically significantly higher risk factor in the re-dislocated group (p = 0.041). The complication rate with scleral re-fixation was higher than that in the non-re-dislocated group. No statistically significant differences were observed, except for vitreous hemorrhage (p = 0.024).

CONCLUSIONS

Caution should be exercised when performing sutured scleral fixation of IOL in younger patients, cases of complicated cataract surgery and aphakia, and patients with DM to prevent IOL re-dislocation. Scleral-fixated sutured IOL in eyes with recurrent IOL dislocation seems to be a safe and effective procedure with a relatively low complication rate.

Clinical epidemiology and pharmacoepidemiology studies with real-world databases

Hospital-based registry data, including patients' information collected by academic societies or government based research groups, were previously used for clinical research in Japan. Now, real-world data routinely obtained in healthcare settings are being used in clinical epidemiology and pharmacoepidemiology. Real-world data include a database of claims originating from health insurance associations for reimbursement of medical fees, diagnosis procedure combinations databases for acute inpatient care in hospitals, a drug prescription database, and electronic medical records, including patients' medical information obtained by doctors, derived from electronic records of hospitals. In the past ten years, much evidence of clinical epidemiology and pharmacoepidemiology studies using real-world data has been accumulated. The purpose of this review was to introduce clinical epidemiology and pharmacoepidemiology approaches and studies using real-world data in Japan.

Matrix Metalloproteinase-2 Activated by Ultraviolet-B Degrades Human Ciliary Zonules In Vitro

The ciliary zonules, also known as the zonules of Zinn, help to control the thickness of the lens during focusing. The ciliary zonules are composed of oxytalan fibers, which are synthesized by human nonpigmented ciliary epithelial cells (HNPCEC). The ciliary zonules are exposed to ultraviolet (UV), especially UV-A and UV-B, throughout life. We previously demonstrated that UV-B, but not UV-A, degrades fibrillin-1- and fibrillin-2-positive oxytalan fibers. However, the mechanism by which UV-B degrades oxytalan fibers remains unknown. In this study, we investigate the involvement of matrix metalloproteinase-2 (MMP-2) in the UV-B-induced degradation of fibrillin-1- and fibrillin-2-positive oxytalan fibers in cultured HNPCECs. Enzyme-linked immunosorbent assay revealed that UV-B irradiation at levels of 100 and 150 mJ/cm² significantly increased the level of active MMP-2. Notably, MMP-2 inhibitors completely suppressed the degradation of fibrillin-1- and fibrillin-2-positive oxytalan fibers. In addition, we show that UV-B activates MMP-2 via stress-responsive kinase p38. Taken together, the results suggest that UV-B activates a production of active type of MMP-2 via the p38 pathway, and subsequently, an active-type MMP-2 degrades the fibrillin-1- and fibrillin-2-positive oxytalan fibers in cultured HNPCECs.

Risk Factors for Intraocular Lens Dislocation After Phacoemulsification: A Nationwide Population-Based Cohort Study

PURPOSE

Few studies have measured the incidence and risk factors of intraocular lens (IOL) dislocation in the total population. We investigate the risk factors for IOL dislocation in a nationwide Korean cohort.

DESIGN

Retrospective cohort study.

METHODS

National data on 2,162,191 subjects who underwent cataract surgery were collected from the Health Insurance Review and Assessment service database of health claims from 2009 to 2016. The Health Insurance Review and Assessment database was used to identify potential risk factors for IOL dislocation, including age, sex, and various pre- and postoperative ophthalmic conditions. The hazard ratios (HRs) and confidence intervals (CIs) of these risk factors were assessed with a multivariable-adjusted Cox regression model.

RESULTS

IOL dislocation occurred in 15,170 patients (0.7%) in the cataract surgery cohort (2,162,191 patients). The incidence rate of IOL dislocation peaked at 40-50 years of age, although the mean age of IOL dislocation was 65.25 ± 10.81 years. The average male:female ratio was 1.8. The adjusted HR for IOL dislocation in patients with partial vitrectomy was 11.93 (95% CI 10.95-12.99; P < .0001). Posterior capsulotomy performed within 1 year after the cataract surgery significantly decreased IOL dislocation, with an adjusted HR of 0.48 (95% CI 0.44-0.51; P < .0001).

CONCLUSIONS

IOL dislocation tended to occur in young males. Anterior vitrectomy was a significant risk factor for IOL dislocation, while posterior capsulotomy after surgery was associated with a decreased risk of IOL dislocation.