Capsule complication during cataract surgery: Background, study design, and required additional care

Ethnic Differences in the Rates of Posterior Capsule Rupture and Long-Term Sequelae in Phacoemulsification Cataract Surgery

Purpose The purpose of this study is to investigate the rates of posterior capsular rupture (PCR) and its sequelae during phacoemulsification across different ethnicities. Methods This is a retrospective cohort study of all consecutive phacoemulsification cases complicated by PCR that met the inclusion criteria over a four-year period at a single tertiary eye centre in the United Kingdom (UK). Results PCR occurred in 0.85% of cases overall (157/18,481). PCR rates were 1.8% (26/1485), 1.2% (51/4350), and 0.7% (75/10,927) in African-Caribbean, Indian subcontinent, and Caucasian patients, respectively (p < 0.001). Mean final corrected distance visual acuity improved (p < 0.05) in all ethnic groups (0.40 ± 0.57 logMAR) compared to pre-op (0.78 ± 0.61 logMAR). Post-operative cystoid macular oedema and unstable intraocular pressure rates following PCR did not statistically differ amongst ethnicities (p = 0.37 and p = 0.75, respectively). However, post-operative uveitis rates significantly differed at 11.5%, 15.7%, and 1.3% amongst the three ethnic groups, respectively (p = 0.01). Conclusion This is the first study to highlight a possible link between patient ethnicity and the risk of PCR during phacoemulsification cataract surgery. We observed significantly greater numbers of PCR cases amongst certain ethnic groups (highest in African-Caribbean eyes, then Indian subcontinental eyes, and lowest in Caucasian eyes) within the same multi-cultural urban population. Ethnicity may therefore be a contributing factor for PCR and should potentially be taken into consideration during preoperative risk stratification.

Why Use Ultrashort Pulses in Ophthalmology and Which Factors Affect Cut Quality

The power density of femtosecond lasers and exposure time to the tissue are crucial for a successful procedure in terms of safety and precision. The reduction of the pulse duration allows reducing the quantity of the energy to be delivered to the tissue for disruption with strongly diminished mechanical and thermal collateral damage. The cutting effect of ultra-short pulses is very precise, minimally traumatic, safe, and predictable. Future developments will lead to further energy reductions to achieve optical breakdowns. However, the pulse length cannot be shortened arbitrarily because below 100 fs nonlinear effects can change the process in an unfavorable way. Compared to manual-conventional cataract surgery, femtosecond laser-assisted cataract surgery (FLACS) shows many advantages in clinical application, especially with regard to precision and tissue protection. The femtosecond laser has become particularly important and has made the overall procedure safer when we deal with complex cataract cases such as subluxated lenses. We provide an overview of the evolution of femtosecond laser technology for use in refractive and cataract surgeries. This article describes the advantages of available laser platforms with ultrashort pulses and mainly focuses on the technical and physical backgrounds of ophthalmic surgery technologies.

Prognostic Factors for Low Visual Acuity after Cataract Surgery with Vitreous Loss

Purpose

The purpose of this study is to find prognostic factors associated with low visual acuity in patients experiencing vitreous loss during cataract surgery.

Methods

A retrospective, noncomparative, interventional, case study of patients experiencing vitreous loss during cataract surgery. Data collected included demographics, best corrected visual acuity (BCVA), axial length (AL), presence of ocular comorbidity affecting central vision, timing of intraocular lens (IOL) implantation, position of the implanted lens, and the presence of corneal sutures. Low visual outcome was defined as BCVA < 20/40.

Results

Overall, 179 patients (60.3% males) with a mean age of 73 ± 12 years and axial length of 23.5 ± 1.3 mm with a mean follow-up of 12 ± 13 months were included. In multivariable logistic regression analysis, low visual outcome was independently associated with persisting postoperative complications (OR 6.25, 95% CI 1.378–30.9), preexisting ocular comorbidities (OR 4.45, 95% CI 1.1–18.00), and secondary intraocular lens (IOL) implant (OR 10.36, 95% CI 1.8–60.00). Conversely, pars plana vitrectomy (PPV) for dislocated fragments of lens material, age > 70 years, gender, axial length, degree of surgeon, corneal suturing, and anterior chamber lens implantation were not found to have significant associations with low visual outcomes (P > 0.05).

Conclusions

Low visual outcome after vitreous loss during cataract surgery was associated with ocular comorbidities, secondary IOL implantation, development of cystoid macular edema, and additional surgical complications.

A Composite Risk Score for Capsule Complications Based on Data from the Swedish National Cataract Register: Relation to Surgery Volumes

PURPOSE

To investigate case mix in relation to capsule complication, possible associations between case mix and operation volume, and change in case mix over time.

DESIGN

Register-based study.

PARTICIPANTS

Swedish patients who underwent cataract surgery between 2007 and 2016.

METHODS

Demographics and data on ocular comorbidity, intraoperative difficulties, and capsule complications were registered from 2007 to 2016 and analyzed retrospectively in relation to coded data on individual surgeons' operation volume. Single factor analysis and logistic regression were performed, and a composite risk score was created.

MAIN OUTCOME MEASURES

Risk of capsule complication, given as adjusted and composite odds ratio in relation to cataract surgery volume.

RESULTS

Preoperative and intraoperative variables significantly associated with capsule complications were best-corrected visual acuity (BCVA) ≤0.1 (decimal, adjusted odds ratio [aOR], 1.82; P < 0.001); pseudoexfoliation (PEX) (aOR, 1.53; P < 0.001); sight-threatening ocular comorbidity other than age-related macular degeneration (AMD), diabetic retinopathy, glaucoma, or cornea guttata (aOR, 1.35; P = 0.006); use of Trypan blue (aOR, 1.76; P < 0.001); mechanical pupil dilation (aOR, 1.36; P = 0.024); and iris hooks at the rhexis margin (aOR, 6.99; P < 0.001). The composite risk score was 3.09 ± 6.40 (mean ± standard deviation) for patients with capsule complication and 1.28 ± 1.66 for uncomplicated procedures (P < 0.001). High-volume cataract surgeons (≥500 procedures yearly) had a significantly lower composite risk score (mean risk score ≤1.28; range, 1.01-2.02) compared with low- and medium-volume cataract surgeons (1.34 ± 0.56; range, 1.00-4.55 and 1.49 ± 0.58; range, 1.01-5.19), respectively. During the period 2007-2016, the proportion of patients aged >88 years, patients with BCVA ≤0.1, and patients with intraoperative difficulties decreased.

CONCLUSIONS

Case mix, as calculated from a composite risk score based on preoperative and intraoperative parameters registered in the National Cataract Register (NCR), may contribute to the decrease in capsule complications from 2007 to 2016 and the lower complication rate observed in cases managed by high-volume cataract surgeons.

[Femtosecond laser-assisted cataract surgery and conventional phacoemulsification cataract surgery in patients with lens subluxation]

PURPOSE

To analyze the results of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification cataract surgery (CPCS) in patients with 1-2 degree lens subluxation.

MATERIAL AND METHODS

The follow-up involved 86 patients (89 eyes). The 1^st group comprised 34 patients (35 eyes) that underwent FLACS; the 2^nd group included 52 patients (54 eyes) who underwent CPCS.

RESULTS

At day four of the follow-up central corneal thickness was significantly lower after FLACS (p_m-u=0.024), but the difference did not remain statistically reliable by 1.5 months after the surgery. At discharge day and 4 months after the surgery uncorrected visual acuity (UCVA) after FLACS reliably exceeded UCVA of the 2^nd group patients (p_m-u=0.00) with mean UCVA being 0.61±0.29 and 0.42±0.25 respectively. Internal higher order aberrations (HOA) in 5.0 mm zone in the 1^st group decreased by 4 times and amounted to 0.236±0.06 μm, in the 2^nd group increased by 4.1 times and was 4.606±8.16 μm; the difference between the groups was statistically significant (p_m-u<0.001). Mean endothelial cells density after FLACS was 2551.91±321.55 cells/mm², after CPCS - 2352.35±436.68 cells/mm² (p_m-u<0.005). Complications after FLACS included 2 cases (5.71%) of posterior capsular rupture and 1 case (2.8%) of post-op corneal edema; patients after CPCS had 6 (11.1%) and 12 (22.2%) complication cases respectively.

CONCLUSION

FLACS is the safer and more effective surgery choice for patients with 1-2 degree lens subluxation in comparison with CPCS; it decreases the risk of possible complications and provides faster postoperative rehabilitation.

Posterior capsular complication rates with femtosecond laser-assisted cataract surgery: a consecutive comparative cohort and literature review

Purpose

The aim of the study was to determine whether femtosecond-assisted laser cataract surgery (FLACS) reduces the posterior capsular complication (PCC) rate compared to manual cataract surgery when performed by an experienced surgeon.

Patients and methods

We reviewed 2,021 consecutive FLACS procedures between 1 June 2012 and 30 August 2017. All cases of posterior capsular rupture (PCR) with or without vitreous prolapse or zonular dialysis (ZD) that prevented an in-the-bag placement of the intraocular lens were included. Risk factors were noted and outcomes documented.

Results

Six eyes of 2,021 (0.3%) who underwent FLACS had either a PCR or ZD. One eye (0.25%) of 403 eyes that had manual cataract surgery had a PCR. There was no significant difference in outcomes. Risk factors included advanced age, dense nuclei, pseudoexfoliation and small pupil. Only a single case in the FLACS series may have been directly attributed to the FLACS procedure.

Conclusion

This study provides evidence that there is no significant difference in the PCC rate between FLACS and manual cataract surgery in the hand of an experienced surgeon who performs >350 cases annually. This low rate of complications may be achieved by less experienced surgeons adopting FLACS.

[Capsule rupture and vitrectomy during phacoemulsification]

BACKGROUND

Rupture of the posterior capsule can occur as one of the complications during phacoemulsification.

OBJECTIVE

The aim of this study was to determine whether the risk of capsule rupture depends on the surgeon's concentration or experience, time of day and season, the side to be operated on and anatomy of the eye as well as the frequency with which it can be expected.

MATERIAL AND METHODS

The patient collective was derived from patients who underwent cataract surgery by phacoemulsification between 2004 and 2014. All surgeries were performed by the same surgeon and constituted no primarily combined operations. Thereby, it was determined how many capsule ruptures occurred, with and without vitrectomy.

RESULTS

There were so significant differences between the left or right eye, weekday or month. During the various surgical steps of cataract surgery, the occurrence of capsule rupture was only significantly more frequent at the time of capsule polishing.

CONCLUSION

Compared to the results of other studies, the risk of complications was lower in the operation collective investigated in this study.

Intraoperative Complications of Cataract Surgery in Tehran Province, Iran

PURPOSE

To determine the prevalence and types of intraoperative complications of cataract surgery and examine potential risk factors.

METHODS

Data were obtained from the 2011 Iranian Cataract Surgery Survey in which information about cataract surgeries throughout the nation was collected. In the Province of Tehran, 55 centers and 1 week per season per center were randomly selected for sampling. In each center, the charts of all patients who underwent cataract surgery during the selected weeks (total of 20 weeks per center) were reviewed for data extraction. The prevalence of different types of intraoperative cataract surgery complications were determined, and their relationships with age, sex, surgical method, surgeon, and hospitalization time were examined.

RESULTS

The prevalence of intraoperative complications of cataract surgery was 4.15% (95% confidence interval, 0.94 to 7.36). The prevalence of posterior capsular rupture with vitreous loss, posterior capsular rupture without vitreous loss, retrobulbar hemorrhage, suprachoroidal effusion/hemorrhage, intraocular lens drop, and nucleus drop was 2.86, 0.69, 0.06, 0.39, 0.03, and 0.11%, respectively. The prevalence of cataract surgery complications decreased from 6.95% in 2006 to 3.07% in 2010. The results of multiple logistic regression showed that surgery by residents, nonphacoemulsification methods of surgery, and patient age less than 10 years and more than 70 years were the risk factors for complications.

CONCLUSIONS

This study evaluated the prevalence of intraoperative complications of cataract surgery for the first time in Tehran Province. The prevalence of complications was high in this study. To achieve the goals of the Vision 2020 Initiative and improve surgical quality, it is necessary to minimize complication rates. Factors to note for decreasing complication rates include type of surgery, surgeon experience, and patient age.

Patient considerations in cataract surgery - the role of combined therapy using phenylephrine and ketorolac

Cataract, a degradation of the optical quality of the crystalline lens, progressive and age-related, is the leading cause of treatable blindness worldwide. Cataract surgery is the most common surgical procedure performed by ophthalmologists and is the only effective treatment for cataracts. Advances in the surgical techniques and better postoperative visual outcomes have progressively changed the primary concern of cataract surgery to become a procedure refined to yield the best possible refractive results. Sufficient mydriasis during cataract removal is critical to a successful surgical outcome. Poor pupil dilation can lead to serious sight-threatening complications that significantly increase the cost of surgery and decrease patients comfort. Mydriasis is obtained using anticholinergic and sympathomimetic drugs. Phenylephrine, an α1-adrenergic receptor agonist, can efficiently dilate the pupil when administered by intracameral injection. Additionally, nonsteroidal anti-inflammatory drugs (NSAIDs) like ketorolac, which inhibit the synthesis of prostaglandins, are used to decrease intraoperative miosis, control pain and inflammation associated with cataract surgery, and to prevent the development of cystoid macular edema following surgery. Recently, a new combination of phenylephrine and ketorolac (Omidria^®) has been approved by United States Food and Drug Administration for use during cataract surgery to maintain intraoperative mydriasis, prevent miosis, and reduce postoperative pain and inflammation. Clinical trials have shown that this new combination is effective, combining the positive effects of both drugs with a good safety profile and patient tolerability. Moreover, recent reports suggest that this combination is also effective in patients with high risk of poor pupil dilation. In conclusion, cataract is a global problem that significantly affects patients' quality of life. However, they can be managed with a safe and minimally invasive surgery. Advances in surgical techniques and newer pharmacological agents such as the combination of phenylephrine and ketorolac, together with better intraocular lenses, have greatly improved visual outcomes and thus patients' expectations regarding visual recovery are also increasing.

Efficacy and safety of femtosecond laser-assisted cataract surgery versus conventional phacoemulsification for cataract: a meta-analysis of randomized controlled trials

The aim of this study was to evaluate the efficacy and safety of femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification cataract surgery (CPCS) in the treatment of cataract. Randomized controlled trials (RCTs) were searched in PubMed, Embase and the Cochrane Central Register of Controlled Trials. Nine qualified studies with a total of 989 eyes were included. Compared with CPCS, FLACS significantly reduced mean phaco energy and effective phacoemulsification time (EPT) required in the surgery. Central corneal thickness (CCT) was significantly lower in FLACS at 1 day of follow-up, but CCT and corneal endothelial cells count was comparable at 1 week of follow-up or longer. FLACS achieved a better visual outcome at postoperative 1 week and 6 months, but the difference was not significant at postoperative 1-3 months. Regard to surgical complications, the incidences of intraoperative anterior capsule tear, postoperative macular edema and elevated intraocular pressure were similar. In conclusion, femtosecond laser pretreatment can reduce phaco energy and EPT, which may reduce the heat damage to ocular tissues by ultrasound. This novel technique might be beneficial for patients with dense cataract and/or low preoperative endothelial cell values. Well-designed RCTs with longer follow-up are still necessary to provide more reliable evidence.

Complications and outcomes of phacoemulsification cataract surgery complicated by anterior capsule tear

PURPOSE

To study the results of phacoemulsification cataract surgery complicated by anterior capsule tear.

DESIGN

Retrospective interventional controlled case series.

METHODS

Consecutive series of eyes suffering intraoperative anterior capsule tear and others with uneventful cataract surgery at Moorfields Eye Hospital were investigated. Biometric, intraoperative, and postoperative details were recorded. The exclusion criteria were combined surgical procedures, planned manual extracapsular cataract extraction, and history of previous intraocular surgery or eye trauma. The main outcome measures were intraoperative capsule complication rates, refractive and visual outcomes, and incidence of short-term postoperative complications. Two-sided Fisher exact and paired t tests were used for categorical and continuous data, respectively.

RESULTS

The study and control groups included 239 and 212 eyes, respectively. In the study group, planned phacoemulsification was converted to manual extraction in 5 cases (2%); a concurrent posterior capsule rupture occurred in 58 eyes (24%) with a rate of nuclear lens material drop in the posterior segment of 5% (11 cases). Over 11% of eyes (n = 27) underwent unplanned secondary surgical procedures. Overall, the refractive outcomes were poor in 22.4% of eyes (postoperative refraction ≥1 diopter of target), and were statistically worse (P < .0001). A significant visual improvement was observed in the majority of the study group eyes (71%); permanent visual loss occurred in 4 eyes (1.7%).

CONCLUSIONS

Anterior capsule tear can lead to additional intraoperative complications, with a relatively high incidence of secondary interventions. Overall, permanent visual loss can be observed and worse refractive outcomes are to be expected, particularly if the lens is being implanted out of the bag.

Femtosecond laser cataract surgery: challenging cases

PURPOSE OF REVIEW

Emerging data in the peer-reviewed literature indicate that femtosecond laser-assisted cataract surgery (LCS) is a well tolerated and effective alternative to conventional phacoemulsification. Initial reports have largely been based on findings from an optimal patient selection. As confidence with the technology has grown, clinical indications have expanded and the benefit of LCS in high-risk patients with complex cataracts is increasingly being considered.

RECENT FINDINGS

We discuss challenging cataract surgery cases, citing the currently available literature alongside experience from over 3000 completed LCS cases at our centre.

SUMMARY

Current experience is limited. However, LCS platforms are continuously evolving and improving. The results collected to date would suggest that the precision and safety offered by LCS may improve outcomes in these challenging cases.

Impact of increased patient choice of providers in Sweden: cataract surgery

OBJECTIVES

Choice of provider was introduced in Sweden in 2001. Our aim was to describe the scope and character of patient flows and to analyze any differences between patients who chose to move outside of their home county (movers) and those who did not (non-movers) with regard to age, sex, waiting time and level of need.

METHODS

Use of cataract operations between 2005 and 2008 based on data from the National Cataract Register. Data were analysed using descriptive statistics, odds ratios and multivariate regression analysis to compare movers and non-movers. Information on contracting between county councils and providers in other counties was obtained from a survey.

RESULTS

Only 4% of cataract patients were treated by a provider outside their home county. Patient flows were mainly determined by contracts between county councils and providers, and only 1% were considered to be 'true' movers (i.e. patients who were not part of any special contracting agreement). Movers differed from non-movers in that they were on average younger, had less serious visual problems and had shorter waiting times.

CONCLUSION

Though patient flows are minor in scope, the possibility of changing provider has probably been important in tackling long waits in some counties. However, the reform may threaten the equity of health care use.