Cataract extraction outcomes and the prevalence of zonular insufficiency in retinitis pigmentosa

Cataract Surgery Outcomes in Retinitis Pigmentosa A Comparative Clinical Database Study

PURPOSE

To report visual acuity (VA) outcomes, intraoperative and postoperative complications of isolated cataract surgery in eyes with retinitis pigmentosa (RP), compared with non-RP-affected eyes.

DESIGN

Retrospective clinical cohort study.

METHODS

A total of 113,389 eyes underwent cataract surgery between July 2003 and March 2015 at 8 clinical sites in the United Kingdom. Eyes with RP as the only comorbid pathology and eyes without any ocular comorbidities (controls) undergoing cataract surgery were compared. VA at 4 to 12 weeks postoperatively and rates of intraoperative and postoperative complications are reported.

RESULTS

Seventy-two eyes had RP. The mean age in the RP group was 57 ± 15 compared to 75 ± 10 in controls (P < .001). Females represented 46% of RP cases and 60% of controls (P = .06). Preoperative VA (mean LogMAR = 1.03 vs 0.59, P < .001) and postoperative VA (0.71 vs 0.14, P < .001) were worse in RP group. The mean VA gain was 0.25 ± 0.60 LogMAR in RP vs 0.43 ± 0.48 LogMAR in controls (P < .001). There were no significant differences in the rate of intraoperative pupil expansion use, posterior capsular tears, or zonular dialysis. Postoperative cystoid macular edema developed in 6.9% of RP eyes and 1% of controls (P < .001). The need for IOL repositioning or exchange was not statistically different between the two groups.

CONCLUSION

Cataract surgery can improve vision in eyes with RP and cataract. Intraoperative complications were similar to control eyes; however, RP eyes experienced more frequent postoperative cystoid macular edema.

Let-7c-3p suppresses lens epithelial-mesenchymal transition by inhibiting cadherin-11 expression in fibrotic cataract

Fibrotic cataract, including anterior subcapsular cataract (ASC) and posterior capsule opacification, always lead to visual impairment. Epithelial-mesenchymal transition (EMT) is a well-known event that causes phenotypic alterations in lens epithelial cells (LECs) during lens fibrosis. Accumulating studies have demonstrated that microRNAs are important regulators of EMT and fibrosis. However, the evidence explaining how microRNAs modulate the behavior and alter the cellular phenotypes of the lens epithelium in fibrotic cataract is insufficient. In this study, we found that hsa-let-7c-3p is downregulated in LECs in human ASC in vivo as well as in TGFβ2-induced EMT in vitro, indicating that hsa-let-7c-3p may participate in modulating the profibrotic processes in the lens. We then demonstrated that overexpression of hsa-let-7c-3p markedly suppressed human LEC proliferation and migration and attenuated TGFβ2-induced EMT and injury-induced ASC in a mouse model. In addition, hsa-let-7c-3p mediated lens fibrosis by directly targeting the CDH11 gene, which encodes cadherin-11 protein, an important mediator in the EMT signaling pathway. It decreased cadherin-11 protein expression at the posttranscriptional level but not at the transcriptional level by binding to a specific site in the 3-untranslated region (3'-UTR) of CDH11 mRNA. Moreover, blockade of cadherin-11 expression with a specific short hairpin RNA reversed TGFβ2-induced EMT in LECs in vitro. Collectively, these data demonstrated that hsa-let-7c-3p plays a clear role in attenuating ASC development and may be a novel candidate therapeutic for halting fibrosis and maintaining vision.

Frequency and Distribution of Ophthalmic Surgical Procedures among Patients with Inherited Retinal Diseases

OBJECTIVE

In this study, we aimed to characterize the frequency and distribution of ocular surgeries in patients with inherited retinal diseases (IRDs) and evaluate associated patient and disease factors.

DESIGN

Retrospective cohort.

PARTICIPANTS

Subjects aged ≥ 18 years who were followed at the Johns Hopkins Genetic Eye Disease Center.

METHODS

We studied a retrospective cohort of patients with an IRD diagnosis to analyze the occurrence of laser and incisional surgeries. Subjects were categorized into 2 groups: central dysfunction (macular/cone/cone-rod dystrophy, "MCCRD group") and panretinal or peripheral dysfunction (retinitis pigmentosa-like, "RP group"). Genetic testing status was recorded. The association of patient and disease factors on the frequency, distribution, and timing of surgeries was analyzed.

MAIN OUTCOME MEASURES

Prevalence, prevalence odds ratio (POR), hazard ratio (HR) of ophthalmic procedures by phenotype.

RESULTS

A total of 1472 eyes of 736 subjects were evaluated. Among them, 31.3% (n = 230) had undergone ocular surgery, and 78.3% of those (n = 180/230) had a history of more than 1 surgery. A total of 602 surgical procedures were analyzed. Cataract extraction with intraocular lens implantation (CEIOL) was the most common (51.2%), followed by yttrium aluminum garnet capsulotomy, refractive surgery, retinal surgery, and others. Cataract extraction with intraocular lens implantation occurred more frequently in RP than in MCCRD subjects (POR, 2.59; P = 0.002). Retinitis pigmentosa subjects underwent CEIOL at a younger age than patients with MCCRD (HR, 2.11; P < 0.001).

CONCLUSIONS

Approximately one-third of patients with IRD had a history of laser or incisional surgery. Cataract extraction with intraocular lens implantation was the most common surgery; its frequency and timing may be associated with the IRD phenotype. This data may inform the design of prospective research. Such efforts may illuminate routine clinical decision-making and contribute to surgical strategy development for cell and gene therapy delivery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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.

Retinitis Pigmentosa: Current Clinical Management and Emerging Therapies

Retinitis pigmentosa (RP) comprises a group of inherited retinal dystrophies characterized by the degeneration of rod photoreceptors, followed by the degeneration of cone photoreceptors. As a result of photoreceptor degeneration, affected individuals experience gradual loss of visual function, with primary symptoms of progressive nyctalopia, constricted visual fields and, ultimately, central vision loss. The onset, severity and clinical course of RP shows great variability and unpredictability, with most patients already experiencing some degree of visual disability in childhood. While RP is currently untreatable for the majority of patients, significant efforts have been made in the development of genetic therapies, which offer new hope for treatment for patients affected by inherited retinal dystrophies. In this exciting era of emerging gene therapies, it remains imperative to continue supporting patients with RP using all available options to manage their condition. Patients with RP experience a wide variety of physical, mental and social-emotional difficulties during their lifetime, of which some require timely intervention. This review aims to familiarize readers with clinical management options that are currently available for patients with RP.

Cataract surgery in patients with retinitis pigmentosa: systematic review

Retinitis pigmentosa (RP) is an inherited bilateral retinal degenerative disease with an incidence of 1 in 4000 people. RP affects more than 1 million individuals worldwide. Although night blindness and restricted visual field are the most typical symptoms of these individuals, generalized vision loss due to cataracts can be expected in the latter stages of the disease. It has been demonstrated that posterior subcapsular cataract is the most prevalent cataract in younger individuals with RP, as opposed to age-related cataracts. Although most ophthalmologists may have a negative view of cataract surgery in patients with RP, it appears that it can play an important role in the visual restoration of patients with RP. However, there are concerns about performing cataract surgery for patients with RP. Herein, a systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses on databases of MEDLINE and Scopus.

Outcome of Cataract Surgery in Patients With Retinitis Pigmentosa

PURPOSE

To assess the visual outcome of cataract surgery in patients with retinitis pigmentosa (RP).

DESIGN

Retrospective, noncomparative clinical study.

METHODS

Preoperative, intraoperative, and postoperative data of patients with RP who were undergoing cataract surgery were collected from several expertise centers across Europe.

RESULTS

In total, 295 eyes of 226 patients were included in the study. The mean age at surgery of the first eye was 56.1 ± 17.9 years. Following surgery, best-corrected visual acuity (BCVA) improved significantly from 1.03 to 0.81 logMAR (ie, 20/214 to 20/129 Snellen) in the first treated eye (-0.22 logMAR; 95% CI = -0.31 to -0.13; P < .001) and from 0.80 to 0.56 logMAR (ie, 20/126 to 20/73 Snellen) in the second treated eye (-0.24 logMAR; 95% CI = -0.32 to -0.15; P < .001). Marked BCVA improvements (postoperative change in BCVA of ≥0.3 logMAR) were observed in 87 of 226 patients (39%). Greater odds for marked visual improvements were observed in patients with moderate visual impairment or worse. The most common complications were zonular dialysis (n = 15; 5%) and (exacerbation of) cystoid macular edema (n = 14; 5%), respectively. Postoperative posterior capsular opacifications were present in 111 of 295 eyes (38%).

CONCLUSION

Significant improvements in BCVA are observed in most patients with RP following cataract surgery. Baseline BCVA is a predictor of visual outcome. Preoperative evaluation should include the assessment of potential zonular insufficiency and the presence of CME, as they are relatively common and may increase the risk of complications.

Use of ellipsoid zone width for predicting visual prognosis after cataract surgery in patients with retinitis pigmentosa

OBJECTIVE

To predict the visual prognosis of cataract surgery in patients with retinitis pigmentosa by measuring ellipsoid zone (EZ) width using spectral-domain optical coherence tomography.

METHODS

This retrospective study included patients with retinitis pigmentosa who underwent uncomplicated cataract surgery between December 2017 and June 2020. Preoperative best-corrected visual acuity (BCVA) and the best postoperative BCVA during follow-up were collected. EZ width was measured on preoperative cross-sectional optical coherence tomography images along the horizontal/vertical meridian through the fovea.

RESULTS

Thirty-eight eyes of 38 patients (22 female; mean [±standard deviation] age, 62.1 ± 11.8 years) were included. The median preoperative logarithm of the minimum angle of resolution BCVA of 0.52 (range, 0.00-3.00) significantly improved to 0.07 (range, -0.18-3.00) after surgery (P < 0.001). On preoperative spectral-domain optical coherence tomography images, the median horizontal, vertical, and average EZ widths were 783 (range, 0-9837), 761 (range, 0-10 250), and 769 (range, 0-10 043) μm, respectively. Postoperative BCVA significantly correlated with the horizontal (r = -0.784, P < 0.001), vertical (r = -0.777, P < 0.001), and average EZ widths (r = -0.777, P < 0.001). The area under the receiver operating characteristic curve for the ability of the horizontal, vertical, and average EZ widths to discriminate eyes with and without postoperative BCVA ≤ 0.3 was 0.971, 0.960, and 0.963, respectively, with best cut-off values of 513, 608, and 515 μm, respectively.

CONCLUSIONS

EZ width measurement can help predict the visual prognosis of cataract surgery in patients with retinitis pigmentosa. A preferable visual acuity prognosis can be expected in patients with an EZ width of approximately 600 μm.

Three-Year Follow-Up of Results of Intraocular Lens Fixation in Patients with Retinitis Pigmentosa

This is a retrospective, consecutive, noncomparative case series of 6 eyes of 5 retinitis pigmentosa (RP) patients who had undergone pars plana vitrectomy (PPV) and intraocular lens (IOL) implantation. The aim of this case series was to report the long-term outcomes of PPV with IOL implantation in patients with RP). The surgical procedures, visual function, refractive error, corneal endothelial cell density, intraocular pressure, and retinal morphology were evaluated before and 3 years after the surgery. Six eyes of 5 RP patients that had undergone PPV and IOL implantation with or without suturing for lens dislocation were studied. The visual acuity was maintained or improved at 3 years after surgery in all 6 eyes. No intraoperative complications occurred in any of the cases. The mean deviation of the Humphrey Field Analyzer 10-2 program and the retinal morphology evaluated by optical coherence tomography did not show any abnormal changes before and after surgery. In two eyes, the postoperative refractive error was more myopic than the attempted refractive error. In conclusion, PPV with IOL implantation can be performed safely in RP patients, and the long-term visual acuity can be maintained.

Current Management Options for Patients with Retinitis Pigmentosa

With an estimated prevalence of 1 in 4000 worldwide [1], retinitis pigmentosa (RP) comprises a spectrum of progressive inherited retinal disorders that can lead to blindness as early as age 30 [2]. Despite its relatively high prevalence and devastating consequences, RP does not have a definitive cure. Therapeutic attempts have been made with nutritional supplementation, but these strategies only have proven benefit in a limited number of patients with rare forms of RP. Thus, current standards of care involve regular follow-up, management of associated ocular pathology such as macular edema and cataracts, and genetic counseling and low vision rehabilitation. In recent years, gene therapy, visual prostheses, and stem cell therapy have emerged as FDA-approved treatments for RP, but these options are not yet widely used. Herein, this chapter will discuss the therapeutic strategies listed above that comprise the current standards of care and briefly discuss some emerging options.

Risk of Cystoid Macular Edema after Cataract Surgery in Retinitis Pigmentosa: An Analysis of United States Claims from 2010 to 2018

PURPOSE

Cataract surgery is commonly performed to improve vision in patients with retinitis pigmentosa (RP). However, the risk of postoperative cystoid macular edema (CME) in RP remains unclear. Here, we leveraged a large multiyear claims database to estimate the risk of CME after cataract surgery in patients with and without RP.

DESIGN

Retrospective multicenter cohort.

SUBJECTS

Patients aged 18 to 65 years who underwent single-phase cataract surgery between January 1, 2020, and December 31, 2018. Identified using the IBM MarketScan claims database.

METHODS

We evaluated the baseline characteristics and outcomes and estimated the hazard ratio (HR) using a multivariable mixed-effects approach. The eyes of patients with RP were categorized as group R1, and those without diagnoses of RP by the time of surgery were categorized as group R0.

MAIN OUTCOME MEASURES

Incident postoperative CME in the same eye that underwent cataract extraction within 12 months of the procedure.

RESULTS

We included 468 123 patients and 615 645 eyes. This included 124 eyes with RP (R1) and 615 521 without RP (R0). The mean ages were 50.5 ± 9.8 years in R1 and 57.9 ± 6.1 years in R0. The cumulative incidence of CME at 12 months was 5.8% (95% confidence interval [CI] 1.2%-10.3%) in R1, and it was 1.1% (95% CI 1.1%-1.2%) in R0. On average, CME was reported in R1 subjects 3.9 weeks later than in R0 subjects (95% CI 2.04-6.5 weeks; P <0.001). The subjects in R1 had 4.83 (95% CI 2.13-10.93, P <0.001) times the risk of CME compared to the subjects in R0. A stratified analysis showed that epiretinal membrane (ERM) decreased the risk of CME in R1 (HR 0.12 [95% CI 0.48-0.97; P = 0.004]) but increased it in R0 (HR, 4.32 [95% CI 3.13-5.95; P <0.001]).

CONCLUSIONS

The cataract surgery-related risk of CME among patients with RP may be >4 times that among people without RP. Men and individuals aged 18 to 34 and 55 to 65 years may be at the greatest risk, whereas ERM may lower the risk. Further study is warranted to stratify the risk by RP genotype and phenotype and illuminate the natural history, angiographic features, and functional consequences of postoperative CME.

Effects and Prognosis of Cataract Surgery in Patients with Retinitis Pigmentosa

INTRODUCTION

Cataract extraction could improve visual acuity (VA) for patients with retinitis pigmentosa (RP), while the surgery may increase photoreceptor degeneration through light damage. In this study, we conducted a systematic review and meta-analysis to investigate the effectiveness and prediction of VA after cataract surgery in patients with RP.

METHODS

We comprehensively extracted data from literature of available studies with quality control processing. Improvement of VA before and after cataract surgery of different durations of follow-up and different structural integrity of the preoperative macular ellipsoid zone (EZ) in patients with RP were compared. VA was measured by the logarithm of the minimum angle of resolution (logMAR).

RESULTS

Sixteen studies were subjected to analysis. Postoperative VA was significantly improved versus preoperative, with a mean difference (MD) of 0.57 [95% confidence interval (CI) 0.45, 0.69], and a fixed-effect model was applied during follow-up durations of 1 day to 1 month (I² = 0%). Similarly, for follow-up durations of 1-3 months, 3-6 months, and 6-12 months, postoperative VAs were all better than preoperative values, with MDs of 0.36 (95% CI 0.31, 0.41), 0.35 (95% CI 0.23, 0.46), and 0.22 (95% CI 0.14, 0.30) (I² < 50%). For follow-up duration of 1-5 years, the random-effect model was applied for higher heterogeneity (I² = 81%), with an MD of 0.26 (95% CI 0.09, 0.43). There was no significant difference in the improvement of the EZ-invisible group, with an MD of 0.27 (95% CI - 0.17, 0.70) (I² = 82%). There were significant differences between EZ-abnormal and EZ-normal groups in preoperative and postoperative VA, with MDs of 0.56 (95% CI 0.27, 0.85) and 0.46 (95% CI 0.27, 0.65) (I² > 50%).

CONCLUSIONS

Cataract surgery could improve VA for patients with RP during long-term follow-up, and the surgery is not recommended for patients with invisible preoperative macular EZ. However, further studies are required to address the problem of excessive light exposure to the degenerated retina in patients with RP with the cataract removed. The study protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022340165).

Bilateral Sequential Spontaneous Anterior Dislocated Intraocular Lens in a Patient With Retinitis Pigmentosa

Retinitis pigmentosa is one of the risk factors for intraocular lens dislocation post cataract surgery which can lead to many complications. A 64-year-old Chinese female with bilateral pseudophakia and retinitis pigmentosa was referred for the continuation of care in 2009 with baseline visual acuity of hand movement bilaterally due to the retinitis pigmentosa. The cataract surgeries with posterior chamber intraocular lens (PCIOL) implantation in her early 50s were uneventful.

In 2011, her right eye PCIOL dislocated anteriorly into the anterior chamber spontaneously and touched the cornea. It was complicated with bullous keratopathy and corneal decompensation. Intraocular pressure (IOP) was normal. PCIOL explantation, anterior vitrectomy and surgical peripheral iridotomy were performed. However, the cornea remained decompensated postoperatively.

Her left eye was stable until 2019 when she developed acute angle closure secondary to complete anterior dislocation of PCIOL with pupillary block glaucoma. She underwent left eye PCIOL explantation, anterior vitrectomy and surgical peripheral iridotomy when IOP was optimised medically. Finally, both eyes were left aphakic due to poor prognosis with light perception (PL) vision, IOP was stable on single topical antiglaucoma and bilateral decompensated corneas were maintained with topical hypertonic saline. This case highlights the different serious sequelae of bilateral eyes in an unfortunate retinitis pigmentosa patient.

Correlation between neutrophil-to-lymphocyte ratio and clinical manifestations and complications of retinitis pigmentosa

PURPOSE

The role of inflammation in retinitis pigmentosa (RP) has been receiving additional attention. However, the association between inflammation and the clinical manifestations and complications of RP is still unclear. This study aimed to evaluate the neutrophil-to-lymphocyte ratio (NLR) of RP complicated with cataract and explore the correlations between the NLR and specific clinical features of RP.

METHODS

This retrospective study included 79 RP patients complicated with cataract (125 eyes) and 63 age- and sex-matched patients (63 eyes) with age-related cataract (ARC). Patients' ocular examination results were collected and complete blood count results were used to calculate NLRs. The correlations between the NLR of RP patients and the parameters of ocular examinations were analysed.

RESULTS

The NLRs of RP patients with cataracts were significantly higher than those of ARC (1.93 ± 0.83 versus 1.65 ± 0.59, p = 0.029). The NLRs increased with the severity of posterior subcapsular cataract (PSC), zonular deficiency, poor preoperative best-corrected visual acuity (LogMAR>1), and visual field defects. Analysis of receiver operating characteristic curves suggested that NLR > 1.36 could predict higher degrees (PSC area >3%, >P1) of PSC (p = 0.002, 95% CI, 0.672-0.934), and that NLR > 2.12 could predict zonular weakness (p = 0.002, 95% CI, 0.665-0.928) in RP.

CONCLUSION

The NLRs in RP patients with cataract are not only higher but also associated with several clinical manifestations of RP. The NLR can be a predictive biomarker of higher degrees of PSC (>P1) and zonular weakness in RP before cataract surgery. These results suggest that systemic inflammation may play a role in the pathogenesis of RP.

Long-term Outcomes of Cataract Surgery in Patients with Retinitis Pigmentosa

PURPOSE

To investigate the long-term outcomes of cataract surgery in patients with retinitis pigmentosa (RP).

DESIGN

Retrospective, observational study.

PARTICIPANTS

Sixty-four patients with typical RP (22 males, 42 females, average age 62.8 ± 10.1 years) who underwent cataract surgery at Kyushu University Hospital between May 2007 and October 2015 and who were followed up for ≥3 years post-surgery.

METHODS

Differences between pre- and post-surgery visual function, including best-corrected visual acuity (BCVA) and parameters in the Humphrey Field Analyzer (HFA) examinations using the central 10-2 program were investigated. The pre-surgery conditions of the foveal ellipsoid zone (EZ) were classified into three grades (grade 1: invisible; grade 2: abnormal; grade 3: normal) based on optical coherence tomography findings.

MAIN OUTCOME MEASURES

BCVA, the retinal sensitivity in HFA 10-2 tests.

RESULTS

Cataract surgery was performed in 96 eyes, with an average follow-up period of 5.8 ± 2.4 years. The mean pre-surgery BCVA was 0.64 ± 0.52 logarithm of the minimum angle of resolution (logMAR), and the final post-surgery BCVA was 0.61 ± 0.67 logMAR (p=0.57). Significant improvement of post-surgery BCVA was observed only in the eyes with preserved foveal EZ (grade 3) (p<0.01). In 62 eyes of the 45 patients who received HFA 10-2 tests, the mean values of deviation, macular sensitivity and foveal sensitivity at the final visit were significantly decreased compared with preoperative values (p<0.01), while those in the grade 3 eyes did not change significantly post-surgery (p=0.13).

CONCLUSIONS

In the long-term course after cataract surgery in RP patients, many cases experienced vision loss with progression of the disease. A preoperative finding of preserved foveal EZ was associated with a better visual prognosis, suggesting that EZ evaluation is useful to predict the long-term visual outcome after cataract surgery in RP patients.

The Impact of Cataract Surgery on Contrast Visual Acuity and Retinal Sensitivity in Patients with Retinitis Pigmentosa

Purpose

To determine the effects of cataract surgery on contrast visual acuity and retinal sensitivity in patients with retinitis pigmentosa.

Methods

Retinal sensitivity and contrast visual acuity were determined by microperimetry (MAIA) and contrast sensitivity acuity tester (CAT-CP), respectively, before and after cataract surgery. The significance of the correlations between visual acuity, retinal sensitivity, contrast visual acuity, improvements after surgery, and macular structure before and after cataract surgery was determined.

Results

Retinal sensitivity and contrast visual acuity were significantly improved after cataract surgery. The correlations among postoperative visual acuity, postoperative retinal sensitivities, and preoperative ellipsoid zone length were significant. The postoperative retinal sensitivity of the central 10° and the ellipsoid zone length was particularly significantly correlated. Preoperative contrast visual acuity and the amount of improvement and preoperative retinal sensitivity and the amount of improvement were significantly negatively correlated. The contrast visual acuity under both the 100% and 10% photopic and mesopic conditions improved significantly after cataract surgery.

Conclusions

Cataract surgery in retinitis pigmentosa patients with preserved ellipsoid zones significantly improved retinal sensitivity and contrast visual acuity. Cataract surgery can be expected to improve retinal sensitivity and contrast visual acuity under various conditions, even if preoperative visual parameters are low, as long as the ellipsoid zone is preserved.

A novel mutation in the PRPH2 gene in a Chinese pedigree with retinitis pigmentosa and angle-closure glaucoma

Background

Retinitis pigmentosa (RP) is a rare, progressive, and hereditary disorder that leads to the progressive loss of vision and visual field, and in some cases blindness. The specific relationship between RP and glaucoma has been debated for decades.

Methods

In this study, we examined a Han RP family with concomitant angle-closure glaucoma (ACG), performed an inductive analysis of their clinical features and assistant results, and applied whole-exome sequencing (WES) technology for a molecular diagnosis.

Results

A novel transversion mutation (c.626 T > A) was identified in the peripherin-2 (PRPH2) gene in the proband, resulting in the substitution of Valine to aspartic acid in codon 209. A full ophthalmic examination showed that the proband with the c.626 T > A mutation had a typical RP manifestation, with close angles; however, the proband’s elder brother, who lacked the novel mutation, had a normal fundus and open angles.

Conclusion

Our results extend the genetic mutation spectrum of PRPH2 in RP, and provide evidence to support a genetic correlation between RP and ACG.

Prevalence of zonulopathy in primary angle closure disease

Background

To determine the prevalence of zonulopathy in a large cohort of eyes with primary angle closure disease (PACD) that underwent cataract surgery.

Methods

Retrospective consecutive case series of PACD eyes (including primary angle closure suspect, primary angle closure, and primary angle closure glaucoma) that underwent phacoemulsification cataract surgery or clear lens extraction between 2009 and 2020 at a single ophthalmology centre. Those with risk factors for zonulopathy such as history of trauma, pseudoexfoliation syndrome, intraocular surgery, retinitis pigmentosa or connective tissue disorders were excluded. The primary outcomes included the prevalence of zonulopathy assessed intraoperatively and secondary pigment dispersion syndrome.

Results

In our cohort of 806 consecutive PACD eyes, the prevalence of zonulopathy was 7.3% (59 of 806 eyes) – significantly greater than the 0.46%–2.6% range reported for the general population (p < 0.001). Intraoperative signs of zonular weakness included floppy capsular bag (29 eyes, 3.6%), zonular laxity (25 eyes, 3.1%) and zonular dehiscence (11 eyes, 1.4%). Among these eyes, capsular tension ring was used in 23 eyes (39.0%), six eyes (10.2%) experienced vitreous prolapse intraoperatively and underwent anterior vitrectomy, and two eyes (3.4%) experienced posterior capsular rupture, one of which required a scleral‐fixated intraocular lens. Secondary pigment dispersion syndrome was observed in 141 eyes (17.5%).

Conclusions

This study evidenced a high prevalence of zonulopathy among a large cohort of PACD eyes and suggests zonulopathy as a possible under‐recognised cause of angle closure. Until more sophisticated imaging modalities become available, awareness about the prevalence of zonulopathy in angle closure disease coupled with careful preoperative examinations can help minimise or prevent the complications of zonulopathy.

Effect of lens capsular tension ring on preventing capsular contraction syndrome in the surgery of retinitis pigmentosa combined with cataract: Retrospective case series

PURPOSE

To observe the effect of phacoemulsification and intraocular lens (IOL) implantation with or without lens capsular tension ring (CTR) on retinitis pigmentosa (RP) combined with cataract patients.

DESIGN

Retrospective cases series study.

METHODS

Sixty-three cases (84 eyes) of RP with cataract were collected, including 30 males and 33 females. Phacoemulsification with 3.0 mm clear corneal incision was performed in all the patients. IOL and CTR implantation were performed in 44 eyes, and IOL implantation alone was performed in 40 eyes. All cases were followed up at 1 day, 1 week and 1, 3, 6,12 months after the surgery to compare the best-corrected visual acuity (BCVA), intraocular pressure (IOP), corneal endothelial cell count (ECC) and complications before and after the surgery.

RESULTS

All surgery were successfully completed by the same physician, and IOL and CTR were all implanted in capsule without complications. The BCVA at 6 months after surgery was 0.91 ± 0.88 LogMAR, showing an improvement compared with the BCVA(1.3 ± 0.7LogMAR) before surgery and there was a statistically significant difference (P = .003). Four cases of capsule contraction syndrome (CCS) occurred in no CTR implantation group and there was no CCS in CTR group. There was a statistically significant difference in the incidence of CCS between two groups (P = .047).

CONCLUSIONS

Phacoemulsification for RP combined with cataract is safe and reliable, and CTR implantation is conducive to reducing the complications caused by capsule contraction.

Long-term Clinical Outcomes of Cataract Surgery in Patients with Retinitis Pigmentosa

Purpose: The long-term clinical outcomes of cataract surgery in patients with retinitis pigmentosa (RP) were evaluated. Methods: A retrospective analysis of medical records was performed for patients who were diagnosed with RP and underwent cataract surgery. Preoperative best-corrected visual acuity (BCVA) was compared with BCVA at 1 month postoperatively and at the final visit. The proportion of patients with cystoid macular edema development or aggravation after surgery was evaluated, as was the proportion of patients with intraocular lens subluxation/dislocation. For patients who underwent optical coherence tomography, factors associated with a BCVA of 0.5 or better at 1 month were analyzed. Results: In total, 133 eyes were included and the mean follow-up period was 58.7 months. The mean logarithm of minimal angle of resolution BCVA was 0.69 ± 0.65 at diagnosis. The BCVA was significantly improved to 0.51 ± 0.47 at 1 month postoperatively (p < 0.001). However, the BCVA at the final visit (0.70 ± 0.81) was similar to the baseline value (p = 1.000). Cystoid macular edema development or aggravation was noted in 8 eyes (6.0%) and intraocular lens subluxation/dislocation was noted in 4 eyes (3.0%). A subgroup analysis involving 108 eyes revealed that preoperative BCVA (p < 0.001) and ellipsoid zone status (p = 0.001) were associated with postoperative visual acuity. Conclusions: Short-term outcomes of cataract surgery in patients with RP were comparatively good. However, long-term visual deterioration was noted with disease progression. Preoperative BCVA and ellipsoid zone status are useful markers for predicting short-term visual outcomes.

Cataract surgery in retinitis pigmentosa

Purpose:

The aim of this study was to evaluate visual outcomes of cataract surgery in patients with retinitis pigmentosa.

Methods:

This retrospective case series includes a review of the medical records of all patients with retinitis pigmentosa undergoing cataract surgery between 2005 and 2018. The primary outcome measure was corrected distant visual acuity and change in vision impairment after surgery.

Results:

Of the 103 (132) patients, 60 (58.3%) were men and 43 (41.7%) were women. The mean age of the study population was 51.3 ± 11.3 (22–74) years. The mean symptom duration was 35.4 ± 44.5 (1–300) months. The most common morphology of cataracts was a combination of nuclear sclerosis, posterior subcapsular, and cortical cataract (n = 65 eyes, 49.3%). Phacoemulsification (87 eyes, 65.9%) was the preferred surgical technique. The mean preoperative corrected distant visual acuity of 1.21 ± 0.87 log MAR units improved significantly (P < 0.001) to 0.60 ± 0.56 log MAR units after surgery. The number of blind patients reduced from 27 (26.2%) to 8 (7.8%) patients. Zonular dialysis and posterior capsule tear were seen in six (4.5%) eyes each. Good preoperative vision (odds ratio: 6.1 [95% confidence interval: 2.9–13.0], P < 0.0001) was associated with better outcome, wheras reduced central macular thickness (odds ratio: 3.5 [95% confidence interval: 1.3–9.2], P = 0.011) was associated with poor outcome.

Conclusion:

A considerable number of patients presented with advanced cataracts and severe vision impairment. Significant improvement in visual acuity and alleviation of vision impairment was seen after surgery, with few complications. Good preoperative visual acuity predicted a good outcome, whereas macular thinning predicted a poor outcome.

Retinitis pigmentosa-associated anterior subcapsular cataract: morphological features and visual performance

PURPOSE

To investigate the morphological features and surgical outcomes of retinitis pigmentosa (RP)-associated anterior subcapsular cataract (ASC).

METHODS

Consecutive RP-associated ASC cases were reviewed, and one hundred patients (171 eyes) were included. Anterior segment photographed images by slit-lamp microscope were reviewed. Best-corrected visual acuity (BCVA) was recorded. The cases were classified according to preoperative best BCVA, the area (central, midperipheral and peripheral) and the density (Grade 1, vacuolar/bubble-like; Grade 2, plaque-like/translucent; and Grade 3, fibrotic/opaque) of ASC; subgroup analysis of surgical outcomes was then performed.

RESULTS

The mean age was 52.1 ± 13.7 years, and the 41-50-year group had the best BCVA. 13.5% of eyes had BCVA better than 20/63, 30.4% were between 20/400 and 20/63, and 56.1% were worse than 20/400. The percentage of ASCs in the central, midperipheral and peripheral areas was 55.0%, 37.4% and 7.6%, respectively. Postoperative BCVA was improved in the central and midperipheral groups (P < 0.001) but was not in the peripheral group (P = 0.07). The percentage of ASCs in density of Grade 1, 2 and 3 was 11.1%, 38.6% and 50.3%, respectively. Grade 2 and 3 achieved improved postoperative BCVA (P < 0.001), but Grade 1 did not (P = 0.693).

CONCLUSIONS

Mostly, ASC is located at the center of the pupillary area and affected the residual vision of RP patients. The patients benefited from cataract removal except for those with ASC extended to peripheral area. Surgery was also recommended for RP with ASC developed to be plaque-like and even fibrotic.

A Case-Cohort Study of Exfoliation Risk Factors and Literature Review

The purpose of the study is to evaluate the risk factors associated with exfoliation in a case-cohort setting and literature review. This single-center, prospective, case-cohort study was carried out from January 2010 to April 2020 on patients operated for cataract surgery by a single surgeon in Lebanon. Forty-nine consecutive patients with exfoliation syndrome (XFS) and 62 consecutive control patients were identified and further investigated for selected systemic (diabetes mellitus, systemic hypertension, asthma, or atopy) and ocular variables (baseline vision, severity of nuclear sclerosis, glaucoma, eye rubbing, history of dry eye, or allergic eye disease). The mean baseline Snellen visual acuity was 20/283 in XFS versus 20/145 in control cases (P = 0.012). XFS also demonstrated significantly denser nuclear sclerosis than controls (P = 0.00958). By univariate analysis, allergic conjunctivitis (15 [30.6%] vs. 2 [3.2%]; P < 0.001), dry eye (20 [40.8%] vs. 13 [21.0%]; P = 0.0133), and habitual rubbing of the eyes (33 [67.3%] vs. 19 [30.6%]; P < 0.001) were associated with the presence of XFS. Habitual ocular rubbing was closely associated with allergic conjunctivitis (odds ratio [OR] = 13.0; 95% confidence interval [CI]: 2.8–58.8; P = 0.032). After multivariable analysis, the following variables showed significant results: glaucoma (OR = 34.5; 95% CI: 4.4–250; P = 0.010), duration of surgery (OR = 5.6; 95% CI 2.43–12.9; P < 0.001), and habitual ocular rubbing (OR = 4.42; 95% CI: 1.97–9.90; P = 0.029). This study shows a novel potential correlation between eye rubbing and XFS in a Lebanese cohort. Chronic eye rubbing induces or may exacerbate preexistent zonular damage in subjects with XFS, hence the need to better manage concurrent ocular surface disorder in these patients.

Cohen Syndrome-Associated Cataract Is Explained by VPS13B Functions in Lens Homeostasis and Is Modified by Additional Genetic Factors

Purpose

Cohen syndrome (CS) is a rare genetic disorder caused by variants of the VPS13B gene. CS patients are affected with a severe form of retinal dystrophy, and in several cases cataracts also develop. The purpose of this study was to investigate the mechanisms and risk factors for cataract in CS, as well as to report on cataract surgeries in CS patients.

Methods

To understand how VPS13B is associated with visual impairments in CS, we generated the Vps13b^{∆Ex3/∆Ex3} mouse model. Mice from 1 to 3 months of age were followed by ophthalmoscopy and slit-lamp examinations. Phenotypes were investigated by histology, immunohistochemistry, and western blot. Literature analysis was performed to determine specific characteristic features of cataract in CS and to identify potential genotype–phenotype correlations.

Results

Cataracts rapidly developed in 2-month-old knockout mice and were present in almost all lenses at 3 months. Eye fundi appeared normal until cataract development. Lens immunostaining revealed that cataract formation was associated with the appearance of large vacuoles in the cortical area, epithelial–mesenchymal transition, and fibrosis. In later stages, cataracts became hypermature, leading to profound retinal remodeling due to inflammatory events. Literature analysis showed that CS-related cataracts display specific features compared to other forms of retinitis pigmentosa-related cataracts, and their onset is modified by additional genetic factors. Corroboratively, we were able to isolate a subline of the Vps13b^{∆Ex3/∆Ex3} model with delayed cataract onset.

Conclusions

VPS13B participates in lens homeostasis, and the CS-related cataract development dynamic is linked to additional genetic factors.

Management of cataract in a case of retinitis pigmentosa with bilateral pseudoexfoliation syndrome

Retinitis pigmentosa (RP) patients are at higher risk for macular oedema, anterior capsular phimosis and spontaneous dislocation of the implanted lens after cataract surgery. A 70-year-old hypertensive woman presented with diminution of vision in her left eye since 2 years. She had history of cataract surgery in the right eye 1 year ago. Her visual acuity was 20/200 in right eye and hand movements in left eye. Slit-lamp examination showed anterior capsular phimosis with intraocular lens in the right eye and pseudoexfoliation in both the eyes. Fundus examination revealed features of RP in both the eyes. Optical coherence tomography showed bilateral foveal atrophy. The patient underwent phacoemulsification cataract surgery with intraocular lens implantation in left eye and Nd:YAG laser capsulotomy in right eye. Postoperative best corrected distance visual acuity was 20/125 in right eye and 20/80 in left eye. This case highlights a rare coincidence of pseudoexfoliation syndrome in a patient with RP and the precautions undertaken during cataract surgery for an optimal visual outcome.

Ocular abnormalities in a large patient cohort with retinitis pigmentosa in Western China

Background

To report the prevalence of ocular abnormalities and investigate visual acuity in a large cohort of retinitis pigmentosa (RP) patients in Western China.

Methods

The medical records and ophthalmic examination reports of 2127 eyes of 1065 RP patients at one eye hospital were retrospectively reviewed to determined the prevalence of ocular abnormalities and the relationship between best corrected visual acuity (BCVA) and macular abnormalities.

Results

Nyctalopia (58.2%) and blurred vision (27.1%) were the leading reasons for RP patients to request an ophthalmic examination. BCVA measurements in the better eyes at first clinical presentation showed that 304 patients (28.5%) were categorised as blind and 220 patients (20.7%) as low vision. The most common ocular abnormalities were macular abnormalities (59.7%) and cataracts (43.1%). The macular abnormalities included epiretinal membranes (51.1%), cystoid macular edema (18.4%), vitreomacular traction syndrome (2.4%), macular holes (2.3%) and choroidal neovascular membranes (0.05%). Glaucoma was found in 35 eyes (1.6%). The proportions of epiretinal membranes (p = 0.001) and macular holes (p = 0.008) increased significantly with age. Cystoid macular edema was significantly associated with poorer visual acuity in RP patients with clear lens (p = 0.002).

Conclusion

Cataracts and macular abnormalities are common in RP patients. Of the macular abnormalities, cystoid macular edema may have a negative effect on BCVA in RP patients with clear lens. Therefore, optical coherence tomography screening in RP patients is highly recommended for early detection and treatment of maculopathy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-020-01797-z.

A Review of Complicated Cataract in Retinitis Pigmentosa: Pathogenesis and Cataract Surgery

Retinitis pigmentosa (RP) is a set of inherited retinal degenerative diseases that affect photoreceptor and retinal pigment epithelial cells (RPEs), possibly associated with some ocular complications, including cataract. The complicated cataract formation is most likely the result of RP-related inflammation response, and the most common morphology category is posterior subcapsular cataract (PSC). Despite the absence of curative pharmacologic treatment, phacoemulsification with intraocular lens implantation to deal with opacification in the lens is preferred due to the considerable visual outcomes. However, the incidence of intraocular and postoperative complications is higher in RP patients than those without, including intraoperative phototoxic retinal damage, posterior capsular opacification (PCO), capsular contraction syndrome (CCS), pseudophakic cystoid macular edema (PCME), increased postoperative intraocular pressure (IOP), and intraocular lens (IOL) dislocation. Hence, it needs much attention to surgery progress and close follow-up. In this review, we discuss the current understanding of RP patients with complicated cataracts from morphology to potential pathogenesis to cataract surgical procedure and provide a concise description and the recommended management of related surgery complications to broaden the knowledge and lower the latent risks to yield better clinical outcomes.

Intraocular Lens Dislocation into the Anterior Chamber because of Repeated Eye-Poking in a Patient with Leber's Congenital Amaurosis

The dislocation of a posterior chamber intraocular lens (PC IOL) because of constant eye rubbing is unusual and has never been reported in a child with Leber's congenital amaurosis (LCA). A 4-year-old full-term girl with an ocular history of LCA presented to the emergency room with a single-piece PC IOL dislocated into the anterior chamber (AC) of the left eye. There was no history of trauma or any other surgical intervention. A specific behavior known as Franceschetti's oculo-digital sign is a characteristic feature of LCA; this sign consists of repeated pressing, poking, and rubbing of the eyes with knuckles and fingers to stimulate the photoreceptors. This behavior caused the dislocation of the PC IOL into the AC. The dislocated IOL was explanted, and the patient was provided with aphakic glasses.

Cataract surgery in patients with late-onset retinal degeneration

PURPOSE

To review the outcomes in a series of patients with long anterior lens zonular fibers associated with late-onset retinal degeneration who had phacoemulsification cataract surgery.

SETTING

Newcastle Eye Centre, Newcastle upon Tyne, United Kingdom.

DESIGN

Retrospective case series.

METHODS

Inclusion criteria were patients with genetically confirmed late-onset retinal degeneration requiring cataract surgery. Perioperative data relating to surgery were collected. In addition, the corrected distance visual acuity (CDVA) and retinal imaging data were recorded. Selected lens capsules were examined using immunohistochemistry or scanning electron microscopy (SEM).

RESULTS

Eleven eyes of 7 patients were included. The long anterior lens zonular fibers made capsulorhexis challenging; however, it was completed safely in all cases. There were no intraoperative or postoperative issues with lens stability. The CDVA improved postoperatively in those cases with intact foveal photoreceptors and retinal pigment epithelium. Over the longer term, the CDVA slowly declined because of progressive atrophy of the macula. Most patients noticed a subjective improvement in vision, even those with advanced disease at baseline. Immunohistochemistry showed that the C1QTNF5 protein was expressed within the lens capsule epithelial cells, although SEM of the long anterior lens zonular fibers showed them to be smaller in diameter than normal anterior lens zonular fibers and to be composed of a helix of fibers.

CONCLUSIONS

In this small series of patients with late-onset retinal degeneration, cataract surgery was successfully performed without long-term complications involving intraocular lens stability. The objective improvement in CDVA seemed to be limited to patients with good foveal photoreceptor architecture.

Creating Hybrid Monovision with 7.0 mm XL Optic and High-Add AMD Intraocular Lenses (XL-MAGS) in a Patient with Retinitis Pigmentosa

We report a case of a patient with progressed retinitis pigmentosa (RP) who underwent bilateral cataract extraction with implantation of a monofocal enlarged optic in the far dominant eye and a high-add AMD intraocular lens (IOL) in the near dominant eye (hybrid monovision XL-MAGS). A 71-year-old woman presented to our clinic complaining of reduced visual acuity additionally to her diagnosis of RP. The high-add IOL LENTIS® MAX LS-313 MF80 (Oculentis, Germany) was implanted in the right eye and the 7.0 mm optic ASPIRA-aXA IOL (HumanOptics, Germany) in the left eye. Six months postoperatively, the uncorrected distance visual acuity improved from hand motion to 0.5 logMAR in the right eye and to 0.3 logMAR in the left eye. Similarly, best corrected near visual acuity significantly improved to 0.4 and 0.7 logMAR, respectively. The patient's subjective quality of life and autonomy improved significantly. RP is a severe retinal disease which leads to loss of vision and typical “tunnel vision” with visual field defects. As this genetic disorder is incurable, many ophthalmologists are not willing to perform cataract surgery. However, this case report shows that creating hybrid monovision with a high-add lens and a 7.0 mm optic IOL led to improvement of visual function and, more importantly, enhanced quality of life and self-autonomy of the patient.

Prevalence of cystoid macular oedema, epiretinal membrane and cataract in retinitis pigmentosa

Background/Aims

To report the prevalence of treatable complications (cystoid macular oedema, CME; epiretinal membrane, ERM and cataract) in patients with retinitis pigmentosa (RP).

Methods

Consecutive patients with RP attending a tertiary eye clinic in 2012. Spectral domain-optical coherence tomography was used to determine presence of CME and ERM. Clinic records were reviewed to identify cataract and pseudophakia. Multivariable analyses adjusted for age, gender and other confounders.

Results

Data are presented for 338 eyes from 169 patients. CME was present in 58.6% of patients and 50.9% of eyes and was bilateral in 73.7%. ERM, cataract and pseudophakia were present in 22.8%, 23.4% and 11.2% eyes, respectively. In multivariable analyses, CME was associated with younger age (OR 0.81, 95% CI 0.67 to 0.98) but not with gender. Patients with ERM and cataract/pseudophakia were less likely to also have CME (OR 0.19, 95% CI 0.09 to 0.40 and OR 0.37, 95% CI 0.16 to 0.84, respectively). CME was most prevalent in patients with autosomal-dominant inheritance (71.4%), followed by autosomal recessive/sporadic inheritance (58.9%) and least likely in persons with X linked inheritance (12.5%, p<0.001).

Conclusions

The prevalence of treatable RP complications is high and suggests it may be clinically beneficial to screen patients with RP to identify those who may benefit from current or future interventions.

Non-syndromic retinitis pigmentosa

Retinitis pigmentosa (RP) encompasses a group of inherited retinal dystrophies characterized by the primary degeneration of rod and cone photoreceptors. RP is a leading cause of visual disability, with a worldwide prevalence of 1:4000. Although the majority of RP cases are non-syndromic, 20-30% of patients with RP also have an associated non-ocular condition. RP typically manifests with night blindness in adolescence, followed by concentric visual field loss, reflecting the principal dysfunction of rod photoreceptors; central vision loss occurs later in life due to cone dysfunction. Photoreceptor function measured with an electroretinogram is markedly reduced or even absent. Optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging show a progressive loss of outer retinal layers and altered lipofuscin distribution in a characteristic pattern. Over the past three decades, a vast number of disease-causing variants in more than 80 genes have been associated with non-syndromic RP. The wide heterogeneity of RP makes it challenging to describe the clinical findings and pathogenesis. In this review, we provide a comprehensive overview of the clinical characteristics of RP specific to genetically defined patient subsets. We supply a unique atlas with color fundus photographs of most RP subtypes, and we discuss the relevant considerations with respect to differential diagnoses. In addition, we discuss the genes involved in the pathogenesis of RP, as well as the retinal processes that are affected by pathogenic mutations in these genes. Finally, we review management strategies for patients with RP, including counseling, visual rehabilitation, and current and emerging therapeutic options.

Short-term fluctuation of lens corneal distance and clinical correlation with phacodonesis

BACKGROUND

To analyze the role of short-term lens-corneal distance (LCD) fluctuation in quantifying preoperative phacodonesis and predicting intraoperative zonular weakness.

METHODS

Patients were divided into control (lens without clinical phacodonesis) and study (lens with suspicious and clinical phacodonesis) groups for evaluation. Slit-lamp examination followed by IOLMaster (Carl Zeiss) for LCD assessment was performed. Five readings were taken at five time points (0 s, 15 s, 30 s, 45 s & 60 s) continuously over a minute (short term) for the LCD fluctuation calculation.

RESULTS

A total of 135 eyes (82 controls and 53 study) were assessed. Study group included 32 (60.3%) suspicious and 21 (39.6%) moderate to severe phacodonesis. There was difference between the control and study eyes (p = 0.000) in short-term LCD fluctuation. Twenty-one study eyes (39.6%) showed LCD difference > 1 mm, including 11 eyes (52.3%) with > 2 mm. There was a difference in LCD with respect to severity of phacodonesis (p = 0.000). In the study eyes, 13 eyes underwent glued IOL implantation (clinical phacodonesis - ten, suspicious phacodonesis - three), and two eyes (suspicious phacodonesis) had glued capsular hook. Thirteen eyes (clinical phacodonesis - ten, suspicious phacodonesis - three) required intraoperative vitrectomy due to vitreous ingress. Intraoperative zonular weakness in 62.5% of eyes with suspicious donesis and association (Chi-square = 0.000) of weakness with preoperative LCD fluctuation was noted.

CONCLUSIONS

Short-term lens-corneal distance fluctuation can be used as a parameter for quantifying lens stability and as an aid in assessing the intraoperative risk.

Straylight as an Indicator for Cataract Extraction in Patients with Retinal Dystrophy

PURPOSE

Straylight reduces retinal sensitivity, which is particularly relevant in conditions with retinal dysfunction, such as retinitis pigmentosa (RP). Retinitis pigmentosa is associated with posterior subcapsular cataract (PSC), a cataract type that is known to cause severe disability glare (i.e., straylight). Study purposes were (1) to determine the severity of disability glare before and after cataract extraction (CE) in subjects with retinal dystrophy; (2) to study possible aggravation of disability glare due to the combination of retinal degradation and increased straylight from PSC; and (3) to evaluate whether straylight can be used to support the possible benefit of (early) CE.

DESIGN

Prospective, comparative study.

PARTICIPANTS

Sixteen patients (25 eyes) with retinal dystrophy scheduled for CE participated.

METHODS

Cataract severity was graded according to the Lens Opacities Classification System (LOCS) III. Preoperatively and postoperatively, corrected distance visual acuity (CDVA), spatial contrast sensitivity with the Pelli-Robson chart, and straylight were tested. Retinal function was assessed with Goldmann visual field and temporal contrast sensitivity (TCS). Temporal contrast sensitivity is a flicker test to evaluate central retinal sensitivity isolated from the eye's optical quality. Central retinal structure was assessed with spectral-domain OCT and fundus autofluorescence.

MAIN OUTCOME MEASURES

Preoperative and postoperative straylight were measured using the C-Quant (Oculus Optikgeräte GmbH, Wetzlar, Germany) and expressed as the logarithm of the straylight parameter s: log(s).

RESULTS

The average straylight value was 1.75 preoperatively and 1.45 postoperatively, 7.1 and 3.5 times higher than in a healthy young eye, respectively. Functionally significant improvement, defined as >0.20 log, was found in 72% of eyes for straylight and in 20% of eyes for CDVA. The CDVA and TCS were significantly correlated. Only straylight improvement was related to preoperative values; therefore, straylight was the only parameter that could be used to support postoperative improvement. In retinal dystrophy, eyes with cataract and a preoperative straylight value ≥1.66 log(s), a 50% chance of functionally significant log(s) improvement can be expected.

CONCLUSIONS

In patients with retinal dystrophy, straylight caused by cataract substantially aggravates visual disability, whereas CDVA is less affected. Therefore, straylight is a valuable (additional) indicator for beneficial CE in patients with retinal dystrophy and cataract.

Evaluating Structural Progression of Retinitis Pigmentosa After Cataract Surgery

PURPOSE

To determine whether cataract surgery accelerates disease progression in retinitis pigmentosa (RP).

DESIGN

Retrospective cohort study.

METHODS

Seventy eyes of 40 patients with RP were categorized as having had phacoemulsification with intraocular lens implantation vs no cataract surgery at a single tertiary-level institution. Spectral-domain optical coherence tomography (SDOCT) was used to measure the ellipsoid zone (EZ) width, which has been demonstrated to be a reliable marker of RP severity, at baseline and throughout follow-up (median 768 days). RP progression was calculated as the loss of EZ width over time for all patients. Additional postoperative data were collected for the cataract surgery group, including preoperative and postoperative best-corrected visual acuity, incidence of macular edema, posterior capsular opacification, epiretinal membrane, and intraocular lens subluxation.

RESULTS

Multivariable analysis including age, baseline EZ width, mode of inheritance, and cataract surgery status showed that there was no significant difference in RP progression between the cataract surgery and control groups (P = .23). Mode of inheritance was associated with RP progression, with autosomal recessive RP progressing at 148 μm/year and autosomal dominant RP progressing at 91 μm/year (P = .003). Visual acuity improved in almost all eyes that underwent surgery (17/19, 89%) and remained stable in remaining eyes (2/19, 11%). There was a high incidence of postsurgical posterior capsular opacification (18/19, 95%). There were no serious complications, such as lens subluxation or endophthalmitis.

CONCLUSIONS

Our findings suggest that cataract surgery is a safe and effective means of improving visual acuity in RP patients and that it does not seem to be associated with faster disease progression as measured using SDOCT.

Treatment of retinitis pigmentosa due to MERTK mutations by ocular subretinal injection of adeno-associated virus gene vector: results of a phase I trial

MERTK is an essential component of the signaling network that controls phagocytosis in retinal pigment epithelium (RPE), the loss of which results in photoreceptor degeneration. Previous proof-of-concept studies have demonstrated the efficacy of gene therapy using human MERTK (hMERTK) packaged into adeno-associated virus (AAV2) in treating RCS rats and mice with MERTK deficiency. The purpose of this study was to assess the safety of gene transfer via subretinal administration of rAAV2-VMD2-hMERTK in subjects with MERTK-associated retinitis pigmentosa (RP). After a preclinical phase confirming the safety of the study vector in monkeys, six patients (aged 14 to 54, mean 33.3 years) with MERTK-related RP and baseline visual acuity (VA) ranging from 20/50 to <20/6400 were entered in a phase I open-label, dose-escalation trial. One eye of each patient (the worse-seeing eye in five subjects) received a submacular injection of the viral vector, first at a dose of 150 µl (5.96 × 10(10)vg; 2 patients) and then 450 µl (17.88 × 10(10)vg; 4 patients). Patients were followed daily for 10 days at 30, 60, 90, 180, 270, 365, 540, and 730 days post-injection. Collected data included (1) full ophthalmologic examination including best-corrected VA, intraocular pressure, color fundus photographs, macular spectral domain optical coherence tomography and full-field stimulus threshold test (FST) in both the study and fellow eyes; (2) systemic safety data including CBC, liver and kidney function tests, coagulation profiles, urine analysis, AAV antibody titers, peripheral blood PCR and ASR measurement; and (3) listing of ophthalmological or systemic adverse effects. All patients completed the 2-year follow-up. Subretinal injection of rAAV2-VMD2-hMERTK was associated with acceptable ocular and systemic safety profiles based on 2-year follow-up. None of the patients developed complications that could be attributed to the gene vector with certainty. Postoperatively, one patient developed filamentary keratitis, and two patients developed progressive cataract. Of these two patients, one also developed transient subfoveal fluid after the injection as well as monocular oscillopsia. Two patients developed a rise in AAV antibodies, but neither patient was positive for rAAV vector genomes via PCR. Three patients also displayed measurable improved visual acuity in the treated eye following surgery, although the improvement was lost by 2 years in two of these patients. Gene therapy for MERTK-related RP using careful subretinal injection of rAAV2-VMD2-hMERTK is not associated with major side effects and may result in clinical improvement in a subset of patients.

All about capsular tension rings

PURPOSE OF REVIEW

To discuss capsular tension devices and recent evidence regarding their use.

RECENT FINDINGS

The capsular tension ring, modified capsular tension ring, and capsular tension segment are well established tools for use during phacoemulsification when zonular instability is present. Recent research has provided additional evidence of their benefits in decreasing intraoperative and postoperative complications.

SUMMARY

Endocapsular support devices allow for cataract surgery success in the setting of zonular instability.

Outcomes following cataract surgery in choroideremia

PurposeTo present a case series of cataract surgery outcomes in choroideremia eyes with an emphasis on the safety of this common operation in advanced stages of the disease.MethodsA single centre retrospective interventional case series comprising six patients with varying degrees of visual loss secondary to choroideremia underwent cataract surgery at a single tertiary eye hospital. Pre- and post-operative best-corrected Snellen visual acuity, spectral domain optical coherence tomography (SD-OCT), and slit lamp examination were performed together with fundus autofluorescence (FAF) and colour fundus photographs.The prevalence of intra- or post-operative complications, post-operative visual outcome, and change in central macular thickness were recorded.ResultsThe pre-operative best-corrected Snellen visual acuity in the operated eyes ranged from 6/12 (20/40) to PL. All but one patient had either an objective or a subjective improvement in visual acuity. There was no evidence of retinal phototoxicity or post-operative cystoid macular oedema (CMO). Three patients developed early capsular fibrosis.ConclusionsAlthough the residual functioning retina in choroideremia patients may be potentially vulnerable, this report finds no evidence of iatrogenic vision loss after uncomplicated cataract surgery. This suggests that cataract surgery may be performed safely in choroideremia patients, although a guarded prognosis for visual improvement should be emphasized in the informed consent.

Clinical characteristics and current therapies for inherited retinal degenerations

Inherited retinal degenerations (IRDs) encompass a large group of clinically and genetically heterogeneous diseases that affect approximately 1 in 3000 people (>2 million people worldwide) (Bessant DA, Ali RR, Bhattacharya SS. 2001. Molecular genetics and prospects for therapy of the inherited retinal dystrophies. Curr Opin Genet Dev 11: 307-316.). IRDs may be inherited as Mendelian traits or through mitochondrial DNA, and may affect the entire retina (e.g., rod-cone dystrophy, also known as retinitis pigmentosa, cone dystrophy, cone-rod dystrophy, choroideremia, Usher syndrome, and Bardet-Bidel syndrome) or be restricted to the macula (e.g., Stargardt disease, Best disease, and Sorsby fundus dystrophy), ultimately leading to blindness. IRDs are a major cause of severe vision loss, with profound impact on patients and society. Although IRDs remain untreatable today, significant progress toward therapeutic strategies for IRDs has marked the past two decades. This progress has been based on better understanding of the pathophysiological pathways of these diseases and on technological advances.

Increased risk of acute angle closure in retinitis pigmentosa: a population-based case-control study

Purpose

To investigate the association between retinitis pigmentosa (RP) and acute angle closure during a 15-year follow-up period.

Methods

Using the Taiwan Longitudinal Health Insurance Database 2000, we identified 382 RP patients based on the diagnostic code of RP (International Classification of Diseases, 9^th Revision, Clinical Modification (ICD-9-CM) 362.74) made during 1996–2010, excluding subjects under age of 20 years at diagnosis or subjects undergoing lens extraction before the index date. The control group included 3820 randomly selected non-RP subjects matched with the RP patients in age, gender and the index date of diagnosis. The incidence of acute angle closure during the study period was observed based on an ICD-9-CM code of 365.22. Cochran-Mantel-Haenszel test was used to determine the odds ratio (OR) of having acute angle closure in RP patients.

Results

The mean age at the diagnosis of RP was 51.1years (standard deviation [SD] 16.7). Acute angle closure occurred in 5 RP patients (1.3%) and in 15 controls (0.4%). The mean age with the acute angle closure was 53.3 years (SD 8.0) in RP patients and 64.6 years (SD 8.4) in controls (P = 0.015). After adjusting for age, gender and comorbid disorders, RP patients had 3.64-fold (95% confidence interval [CI], 1.29–10.25, P<0.001) greater odds of having acute angle closure. After stratification for gender and age, the risk of acute angle closure in RP was higher in patients under age of 60 years (adjusted OR 11.84; 95% CI, 2.84–49.48) and male patients (adjusted OR 19.36; 95% CI, 3.43–109.40)(both P = 0.001).

Conclusions

RP patients had increased risk of acute angle closure than controls. Contrary to the fact that angle closure disease is more prevalent in elderly females in general population, acute angle closure attack occurred earlier in life and the risk was higher in males among RP patients.

Posterior Capsule Opacification After Phacoemulsification: Annual Review

PURPOSE

The purpose of this article is to provide a clinical update on posterior capsule opacification (PCO) after phacoemulsification by reviewing the literature from the last 12 months.

DESIGN

This article is a literature review.

METHODS

The authors conducted a 1-year literature search in the English language on PCO using PubMed. The period used to conduct the literature search was from January 1, 2013, to January 1, 2014. The following search terms were used during the PubMed search: phacoemulsification, microcoaxial incision, posterior capsule opacification, long-term evaluation of intraocular lens (IOL) implantation, IOL edge design and material, surgical technique, anterior capsule overlap on the IOL optic, diabetes mellitus, myopia, pseudoexfoliation, retinitis pigmentosa, uveitis, and neodymium: yttrium-aluminum-garnet laser capsulotomy.

RESULTS

This review incorporates original articles that provided fresh insights and updates on PCO. Particular attention was paid to observational, randomized, controlled clinical trials, as well as analyses of larger cohorts with a prospective and retrospective study design. Letters to the editor, unpublished works, experimental trials and abstracts were not considered.

CONCLUSIONS

This annual review provides a brief update on PCO that might be of interest to the practicing clinical ophthalmologist.