ResearchPad - ophthalmic-procedures https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Factors associated with visual outcomes after cataract surgery: A cross-sectional or retrospective study in Liberia]]> https://www.researchpad.co/article/elastic_article_15712 To report the initial outcomes and associated risk factors for poor outcome of cataract surgery performed in LiberiaMethods and analysisLV Prasad Eye Institute (LVPEI), Hyderabad, started providing eye care in Liberia since July 2017. Electronic Medical Records of 573 patients operated for age-related cataract from July 2017 to January 2019 were reviewed. One eye per patient was included for analysis. All patients underwent either phacoemulsification or manual small incision cataract surgery (MSICS). Pre and postoperative uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) were recorded at one day, 1–3 weeks and 4–11 weeks. Main outcome measure was BCVA at 4–11 weeks; Intraoperative complications and preoperative ocular comorbidities (POC) were noted. BCVA less than 6/12 was classified as visual impairment (VI). Risk factor for VI was analysed using the logistic regression model.ResultsOf the 573 patients, 288 were males and 285 were females (49.7%). Mean age was 65.9±10.9 years; 14.3% had POC. The surgical technique was mainly MSICS (94.59%, n = 542). At 4–11 weeks, good outcome of 6/12 or better was noted in 38.55% (UCVA) and 82.54% (BCVA). Visual acuity (VA) of 6/18 or better as UCVA and BCVA was noted in 63.5% and 88% eyes respectively. Poor outcome of less than 6/60 was noted as UCVA (11.11%) and BCVA (5.22%). Multivariable analysis showed poor visual outcomes significantly higher in patients with POC (odds ratio 3.28; 95% CI: 1.70, 6.34).ConclusionThe cataract surgical outcomes in Liberia were good; with ocular comorbidities as the only risk factor. ]]> <![CDATA[Characterization of limbal explant sites: Optimization of stem cell outgrowth in <i>in vitro</i> culture]]> https://www.researchpad.co/article/elastic_article_14624 Simple limbal epithelial transplantation (SLET) and cultivated limbal epithelial transplantation (CLET) are proven techniques for treating limbal stem cell deficiency (LSCD). However, the precise regions that are most suitable for preparing explants for transplantation have not been identified conclusively. Accordingly, this in vitro study aimed at determining ideal sites to be selected for tissue harvest for limbal stem cell culture and transplantation. We evaluated cell outgrowth potential and the expression of stem cell markers in cultures from 48 limbal explants from five cadaveric donors. The limbal explants were generated from the three specific sites: Lcor (located innermost and adjacent to the cornea), Lm (middle limbus), and Lconj (located outermost adjacent to the conjunctiva). We found that explants from the Lconj and Lm sites exhibited higher growth potential than those from the Lcor site. Transcript encoding the stem cell marker and p63 isoform, ΔNp63, was detected in cells from Lm and Lconj explants; expression levels were slightly, though significantly (p-value < 0.05), higher in Lm than in Lconj, although expression of ΔNp63α protein was similar in cells from all explants. Differential expression of ATP-Binding Cassette Subfamily G Member 2 (ABCG2) did not reach statistical significance. Immunohistochemistry by indirect immunofluorescence analysis of limbus tissue revealed that the basal layer in explant tissue from Lconj and Lm contained markedly more stem cells than found in Lcor explant tissue; these findings correlate with a higher capacity for growth. Collectively, our findings suggest that explants from the Lconj and Lm sites should be selected for limbal cell expansion for both CLET and SLET procedures. These new insights may guide surgeons toward specific limbal sites that are most suitable for stem cell culture and transplantation and may ultimately improve treatment outcomes in the patients with LSCD.

]]>
<![CDATA[Surgical management of intraocular lens dislocation: A meta-analysis]]> https://www.researchpad.co/article/5c76fe14d5eed0c484e5b438

Purpose

To compare the efficacy and safety of intraocular lens (IOL) repositioning and IOL exchange for the treatment of patients with IOL dislocation.

Methods

We systematically searched for relevant publications in English or Chinese in MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, WHO International Clinical Trial Registration Platform, Clinical Trial.gov, China Biology Medicine Database, China National Knowledge Infrastructure Database and grey literature sources. Study quality was assessed using the STROBE template for observational studies and the Cochrane template for randomized controlled trials (RCTs). Data were meta-analyzed using RevMan 5.3.

Results

The review included 14 English-language studies reporting 1 RCT and 13 retrospective case series involving 1,082 eyes. Average follow-up time was 13.7 months. Pooled analysis of 10 studies showed that the two procedures had a similarly effect on best corrected visual acuity (MD -0.00, 95%CI: -0.08 to 0.08, P = 0.99). Pooled analysis of nine studies showed no significant difference in incidence of IOL redislocation (RR 2.12, 95%CI 0.85 to 5.30, P = 0.11); pooled analysis of seven studies showed greater extent of incidence of cystoid macular edema in IOL exchange (RR 0.47, 95%CI 0.21 to 1.30, P = 0.06). Pooled analysis of three studies showed greater extent of incidence of anterior vitrectomy in IOL exchange (RR 0.11, 95%CI 0.04 to 0.33, P<0.0001). Pooled analysis of two studies showed greater postoperative spherical equivalents in IOL repositioning (MD 1.02, 95%CI 0.51 to 1.52, P<0.0001). pooled analysis suggested no significant differences between the two procedures in terms of intraocular pressure, endothelial cell density, surgically induced astigmatism, or incidence of retinal detachment, intraocular hemorrhage or pupillary block.

Conclusion

IOL repositioning and exchange are safe and effective procedures for treating IOL dislocation. Neither procedure significantly affects best corrected visual acuity and IOL redislocation. IOL exchange was superior to repositioning in terms of postoperative SE, but IOL repositioning was associated with lower incidence of anterior vitrectomy, potentially lower incidence of cystoid macular edema.

]]>
<![CDATA[Trinucleotide repeat expansion length as a predictor of the clinical progression of Fuchs’ Endothelial Corneal Dystrophy]]> https://www.researchpad.co/article/5c57e6cbd5eed0c484ef3e0d

Purpose

To determine if CTG18.1 TNR expansion length prognosticates the clinical progression of Fuchs’ Endothelial Corneal Dystrophy (FECD).

Methods

This was a prospective cohort study. A total of 51 patients with newly diagnosed FECD were recruited and followed-up over a period of 12 years, from November 2004 to April 2016. Baseline clinical measurements included central corneal thickness (CCT), endothelial cell density (ECD) and CTG18.1 TNR expansion length from peripheral leukocytes, with yearly repeat measurements of CCT and ECD. A patient was defined to have experienced significant clinical progression and to have developed Threshold Disease if any of these criteria were fulfilled in either eye: a) CCT increased to >700μm, b) ECD decreased to <700 cells/mm2, or c) underwent keratoplasty for treatment of FECD.

Results

Patients were categorized as having at least one allele whose maximum allele length was equal to or greater than 40 repeats (L≥40, n = 22, 43.1%), or having both alleles shorter than 40 repeats (L<40). Threshold Disease rates at the 5-year time point were 87.5% for the L≥40 group and 47.8% for the L<40 group (p = 0.012). This difference narrowed and was no longer statistically significant at the 8-years (92.9% vs 78.9%, p = 0.278) and 10-years (92.9% vs 84.2%, p = 0.426) time points.

Conclusions

L≥40 patients are at greater risk of FECD progression and development of Threshold Disease within the first 5 years following diagnosis.

]]>
<![CDATA[Long-term probability of intraocular pressure elevation with the intravitreal dexamethasone implant in the real-world]]> https://www.researchpad.co/article/5c390b97d5eed0c48491d656

Purpose

To evaluate the long-term cumulative probability of intraocular pressure (IOP) elevation with the intravitreal dexamethasone implant (IDI) when used to treat different indications: diabetic macular edema, uveitis, retinal vein occlusion.

Methods

705 IDI injections (429 eyes) were assessed and Kaplan-Meier graphs were generated to assess: the probability of different levels of IOP elevation (IOP≥21, ≥25 or ≥35 mmHg), IOP change ≥10 mmHg, initiation of IOP-lowering treatment, glaucoma surgery, IOP change with repeat injections and IOP elevation in eyes with glaucoma and ocular hypertension (OHT).

Results

The cumulative probability of IOP ≥21, ≥25 and ≥35 mmHg was 50%-60%, 25%-30% and 6%-7% at 12–24 months, respectively. The probability of initiating IOP-lowering medication was 31%-54% at 12–24 months. Glaucoma and OHT eyes had a higher probability of mild IOP elevation (≥21 mmHg, 65.1%, 75% and 57.8%, p = 0.01), yet a similar moderate (≥25 mmHg, 22.3%, 28% and 30.2%, p = 0.91) and severe elevation of IOP (≥35 mmHg, 3.7%, 7.1% and 4%, p = 0.71) as normal eyes. Glaucoma surgery was required in only 0.9% cases (4/429). At baseline, 8.8% of the treated eyes had glaucoma, 6.7% OHT and 16.9% were already on IOP-lowering medication.

Conclusions

In the long-term (24 months), IOP elevation is common, generally mild (30% IOP, ≥25 mmHg) and well-tolerated, resolving with topical treatment (54%) and rarely requiring surgery (0.9%).

]]>
<![CDATA[Effect of anterior capsule polish on visual function: A meta-analysis]]> https://www.researchpad.co/article/5c3e4f7ad5eed0c484d75cec

Purpose

To investigate the relationship between anterior capsule polish and visual function.

Methods

Data were obtained from Pubmed, Embase, Web of Science, WanFang, VIP and CNKI up to the end of May 2018, without any date or language restrictions for trials. The modified Jadad scale and the newcastle-ottawa scale were used to assess the quality of included studies. Uncorrected visual acuity (UCVA) and posterior capsule opacification (PCO) were used as outcome variables. Data on anterior capsule polish were pooled using weighted, random-effect meta-analysis.

Results

One randomized controlled trial and 4 observational cohort studies involving 2533 patients were included in the analyses. There was a statistically significant difference of UCVA (OR 1.92, 95% CI 1.41–2.61) between the polish group and the control group, indicating that anterior capsule polish improved UCVA. Further studies with continuous data also suggested that anterior capsule polish was associated with good UCVA (MD 0.11, 95% CI 0.06–0.16). Posterior capsule opacification rate for 1-year or longer follow-up were extracted for 2561 eyes in 3 studies. Posterior capsule opacification rate was lower in the anterior capsule polish group according to summary odds ratio on PCO rate (OR 0.42 95% CI 0.24–0.73).

Conclusions

Anterior capsule polish prevents complication of modern cataract surgery and benefits on visual function in short term follow-up period.

]]>
<![CDATA[Predictive factors for efficacy and safety in refractive surgery for myopia]]> https://www.researchpad.co/article/5c1d5bced5eed0c4846eca43

Purpose

To evaluate the predictive factors for safety and efficacy in laser refractive surgery for myopia

Setting

A singular refractive surgery center, at a University-affiliated tertiary medical center.

Design

Retrospective cohort study

Methods

Study population—A total 8,775 eyes having laser refractive laser procedures for myopia (in4,623 patients).

Observation procedures–Using a prospective database of refractive procedures performed over the span of 13 years, variables such as gender, age, type of surgery, date of surgery, pre-operative corneal thickness and Spherical Equivalent (SEQ) were evaluated.

Main outcome measures—Proportion of patients with Safety index higher than 0.85 and Efficacy index higher than 0.80.

Results

91.9% and 86.0% of all evaluated eyes were above the safety and efficacy cut-off levels, respectively. Younger age was significantly correlated with safety and efficacy indices above the cut-off levels (p<0.001). Male gender was significantly correlated with efficacy above the cut-off level (p<0.001). Myopic eyes with lower SEQ were associated with both safety (p = 0.002) and efficacy (p<0.001) indices above the cut-offs. The surgical procedure was found to significantly affect the outcome only using univariate analysis: Safety was higher in Photorefractive Keratectomy (PRK), while Efficacy was higher in Laser Assisted In Situ Keratomileusis (LASIK) (p<0.001, respectively) but no difference was found using multivariate analysis. Safety index above the cut-off level increased over the years (p<0.001).

Conclusions

Efficacy in refractive surgery for myopia is correlated with younger age, male gender and low myopia. Safety is correlated with younger age, low myopia and increases over the years. Multivariate analysis found no differences between PRK and LASIK regarding safety and efficacy.

]]>
<![CDATA[Post-phacoemulsification iris changes in eyes with glaucoma or glaucoma suspect status]]> https://www.researchpad.co/article/5c1c0b0dd5eed0c48442732d

Purpose

This prospective study used anterior segment optical coherence tomography (AS-OCT) to determine how phacoemulsification (phaco) changes iris parameters in eyes with glaucoma or glaucoma suspect status.

Methods

Using Visante AS-OCT (Carl Zeiss Meditec AG), the following pre- and post-phaco parameters were measured: IT750 = iris thickness at 750 μm from the scleral spur; IT2000 = iris thickness 2000 μm from the scleral spur; ITCM = the maximum iris thickness at the middle one third of the iris; ICURV = iris curvature; IAREA = iris area; and pupil size = pupil diameter (mm). Only high-quality images with an identifiable scleral spur were included, and only the nasal quadrant was analyzed. A single glaucoma specialist analyzed the parameters according to the Zhongshan Angle Assessment Program (ZAAP, Guangzhou, China). Multivariate analysis was performed using mixed effects regression correcting for age, gender, and ethnicity.

Results

89 subjects and 110 eyes were included in this study. The mean age of subjects was 74.83 {+/-} 8.69 years old. Most common diagnoses were POAG and glaucoma suspect (23% and 52%, respectively), and 16% of subjects had an LPI. In multivariate analysis of AS-OCT parameters, decreases in IT750, IT2000, ITCM, ICURV, and pupil size were statistically significant (p<0.05).

Conclusions

After phacoemulsification, eyes with glaucoma as well as glaucoma suspect eyes have thinner irises and smaller pupils. This may lead to less iris-mediated aqueous outflow obstruction, providing support for early phacoemulsification glaucoma treatment.

Translational relevance

Our AS-OCT imaging findings may guide clinical practice as iris parameters become increasingly relevant in preoperative phaco planning.

]]>
<![CDATA[A comparison of surgical outcomes between pre-and full-term patients with exotropia]]> https://www.researchpad.co/article/5c141eadd5eed0c484d27ba2

Purpose

To compare the surgical outcomes between pre- and full-term patients with exotropia and to examine the factors associated with surgical outcomes.

Methods

This retrospective study included 48 pre- and 432 full-term patients with basic-type exotropia who underwent unilateral or bilateral lateral rectus muscle (ULR or BLR) recession. Preoperative characteristics and surgical outcomes were compared between the pre- and full-term infants. Additionally, factors affecting the surgical outcomes were evaluated in all patients.

Results

The preoperative characteristics were significantly different between the pre- and full-term groups in terms of neurodevelopmental disabilities (p = 0.020). There were no significant differences between the pre- and full-term groups in terms of the success, overcorrection, and recurrence rates after the mean follow-up period of 34.6 ± 13.9 months (p = 0.697). The major cause of surgical failure was recurrence in both groups. Pre-term birth was not a risk factor for overcorrection and recurrence. However, regardless of the pre- or full-term birth status, the presence of neurodevelopmental disabilities significantly affected final overcorrection (p = 0.004).

Conclusions

Pre-term patients with exotropia showed similar surgical outcomes to full-term controls. The presence of neurodevelopmental disabilities was a risk factor for final overcorrection.

]]>
<![CDATA[Epithelial defects after penetrating keratoplasty in infectious keratitis: An analysis of characteristics and risk factors]]> https://www.researchpad.co/article/5c0841efd5eed0c484fcb332

To investigate the clinical characteristics, treatment, risk factors of occurrence and graft transparency of corneal epithelial defects after penetrating keratoplasty in patients with infectious keratitis. 594 patients (594 eyes) with infectious keratitis treated by penetrating keratoplasty at Shandong Eye Institute were reviewed retrospectively between January 2008 and January 2018. We investigated the demographic data, diameter and sources of graft, onset time, location, scope, time of healing and treatment of epithelial defects, as well as other postoperative complications and graft clarity. 114 of the 594 grafts (19.2%) that developed epithelial defects were included in the epithelial defects group, while the other 480 patients were classified in the non-defect group. The mean age of patients with epithelial defects was statistically greater than that of patients without epithelial defects (P = 0.006). The epithelial defects group accounted for a larger proportion of male patients (P<0.001). The proportion of patients with a graft diameter >9mm in the epithelial defect group (29.8%) was more than that in the non-defects group (16.3%) (P = 0.001). The incidence of epithelial defects significantly differed among the pathogenic causes of infectious keratitis (P = 0.002). The incidence of graft infection (21.1%, 9.2%, respectively, P<0.001) and graft dysfunction (7.9%, 2.5%, respectively, P = 0.012) in the epithelial defect group was higher than in the non-defects group. Multivariate logistic regression revealed that male sex (P = 0.001), age ≥ 60 years (P = 0.024), graft diameter >9mm (P = 0.001), bacterial (P = 0.039) and herpes simplex keratitis (P = 0.008), rheumatism (P = 0.031) and cancer treated with chemo- or radiotherapy (P = 0.032) were independent risk factors for epithelial defects. Graft clarity after epithelial defects were significantly differed between fungal and viral infections (P<0.001). We found that being an elderly male patient, a graft diameter >9 mm, bacterial and viral keratitis and systemic diseases (including rheumatism and cancer treated with chemo- or radiotherapy) were independent risk factors for postoperative epithelial defects.

]]>
<![CDATA[Polyvinyl alcohol-iodine induced corneal epithelial injury in vivo and its protection by topical rebamipide treatment]]> https://www.researchpad.co/article/5c2400dcd5eed0c484099742

Periocular povidone-iodine (PI) and polyvinyl alcohol-iodine (PAI) have had a major role in the prevention of endophthalmitis. The purpose of this study was to investigate the corneal epithelial toxicity of PAI in a rabbit eye model using corneal resistance (CR) measurement, which is a good indicator of cell barrier function. Rabbit eyes were administered PAI solution at 4-, 6-, 8-, or 16-fold dilution with physiological saline solution (saline) or saline alone (control), to the conjunctival sac with/without wash-out with saline. Corneal epithelial injury assessed by fluorescein staining and the CR ratio was measured at 10 minutes (min) to 96 hours (h) after the initial administration. Histological observation was performed in the eyes following the PAI or control administrations. At 120 min after administration of PAI solution, the CR ratio was decreased and superficial punctate keratopathy (SPK) was significantly increased in each of the PAI-administered groups compared to the control. Recovery of CR and SPK after administration of 6- or 8-fold dilution of PAI was significantly delayed in eyes that were not subsequently washed with saline compared with eyes that were. Pre- or post-instillation of 2% rebamipide ophthalmic suspension significantly reduced PAI induced-SPK and -decrease of CR ratio. The CR method was able to accurately and quantitatively evaluate fine corneal epithelial injury. It is suggested that eyes should be washed with saline solution after administration of PAI solution or the instillation of rebamipide to prevent or reduce corneal epithelial injury.

]]>
<![CDATA[Association between vision-specific quality of life and falls in community-dwelling older adults: LOHAS]]> https://www.researchpad.co/article/5aefe68f463d7e5657a08cdb

Background

Falls and fall-related fractures are a major public health problem among the older adults. Although objective measures of poor vision have been reported to be associated with falls, the association of self-reported visual function and vision-specific quality of life (QOL) with falls has been inconsistent across several studies. We investigated the association of self-reported visual function and vision specific QOL with falls in community-dwelling older adults.

Methods

We conducted a cross-sectional analysis using the baseline data from participants of the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS), which is an ongoing population-based cohort study to evaluate the association of physical dysfunction with the clinical outcomes in community-dwelling people. In the present study, the participants aged over 65 years in 2010 were eligible. The exposure variable was the composite score of the VFQ-J11, which was newly developed using item response theory to evaluate vision specific QOL, and the self-reported outcomes were any fall and frequent falls (≥2) over a 1-month period. We estimated odds ratios using separate logistic regression models adjusted for relevant confounding factors.

Results

Among 1624 participants, the median (interquartile range) composite score of VFQ-J11 was 86.8 (76.0–95.9). Any fall and frequent falls were reported by 13.9% and 5.4% of participants, respectively. The composite score of the VFQ-J11 was significantly associated with both frequent falls (adjusted ORs per 10 points, 0.80; 95% CI, 0.68–0.93) and any fall (adjusted ORs per 10 points, 0.84; 95% CI, 0.76–0.94).

Conclusions

We found that the composite score of the VFQ-J11 was associated with falls in community-dwelling older adults. Detecting individuals with visual impairments associated with falls using the VFQ-J11 and improvement in the score by interventions could prevent falls. We may consider adding self-reported visual function and vision-specific QOL to conventional risk factors for fall among older adults.

]]>
<![CDATA[Changes in macular pigment optical density after membrane peeling]]> https://www.researchpad.co/article/5b0436b2463d7e0f0e6b97b7

Introduction

To highlight the differences in macular pigment optical density (MPOD) between eyes with vitreoretinal interface syndrome and healthy control eyes, to assess the changes in MPOD in eyes treated with macular peeling, to investigate the relationships between MPOD changes and measures of retinal sensitivity such as best corrected visual acuity (BCVA) and microperimetry.

Methods

In this cross-sectional comparative study, 30 eyes affected by idiopathic epiretinal membrane (iERM, 15eyes) or full-thickness macular hole (FTMH, 15eyes) were compared with 60 eyes from 30 healthy age-matched patients. MPOD values (mean MPOD, maximum MPOD, MPOD area, and MPOD volume) were measured in a range of 4°–7° of eccentricity around the fovea, using the one-wavelength reflectometry method (Visucam 200, Carl-Zeiss Meditec). Patients affected by iERM and FTMH were treated with vitrectomy and epiretinal membrane-inner limiting membrane (ERM-ILM) peeling, with follow-up examinations performed preoperatively and 6 months postoperatively. The main outcome measures were the differences in MPOD between eyes with vitreoretinal interface syndrome and healthy eyes, changes in MPOD after ERM-ILM peeling, and relationships between MPOD and functional changes.

Results

Mean MPOD differed significantly between control eyes and those with iERM (P = .0001) or FTMH (P = .0006). The max MPOD and MPOD area increased, but not significantly. After peeling, the only significant change in MPOD was in MPOD volume (P = .01). In the ERM group, postoperative mean MPOD correlated significantly with best-corrected visual acuity (r = .739, P = .002).

Conclusions

MPOD was reduced in patients with iERM or FTMH compared with healthy eyes. We found a significant correlation between the mean postoperative MPOD and postoperative BCVA, hypothesizing that the postoperative increase in mean MPOD could be due to a change in distribution for unfolding and expansion of the fovea after the peeling. MOPD may be considered as a prognostic factor associated with a good visual prognosis in patients with iERM.

]]>
<![CDATA[Immunological Properties of Corneal Epithelial-Like Cells Derived from Human Embryonic Stem Cells]]> https://www.researchpad.co/article/5989daddab0ee8fa60bbab19

Transplantation of ex vivo expanded corneal limbal stem cells (LSCs) has been the main treatment for limbal stem cell deficiency, although the shortage of donor corneal tissues remains a major concern for its wide application. Due to the development of tissue engineering, embryonic stem cells (ESCs)-derived corneal epithelial-like cells (ESC-CECs) become a new direction for this issue. However, the immunogenicity of ESC-CECs is a critical matter to be solved. In the present study, we explored the immunological properties of ESC-CECs, which were differentiated from ESCs. The results showed that ESC-CECs had a similar character and function with LSCs both in vitro and in vivo. In ESC-CECs, a large number of genes related with immune response were down-regulated. The expressions of MHC-I, MHC-II, and co-stimulatory molecules were low, but the expression of HLA-G was high. The ESC-CECs were less responsible for T cell proliferation and NK cell lysis in vitro, and there was less immune cell infiltration after transplantation in vivo compared with LSCs. Moreover, the immunological properties were not affected by interferon-γ. All these results indicated a low immunogenicity of ESC-CECs, and they can be promising in clinical use.

]]>
<![CDATA[SiRNA Targeting mTOR Effectively Prevents the Proliferation and Migration of Human Lens Epithelial Cells]]> https://www.researchpad.co/article/5989daf8ab0ee8fa60bc3aff

Posterior capsule opacification (PCO) is the most common complication that causes visual decrease after extracapsular cataract surgery. The primary cause of PCO formation is the proliferation of the residual lens epithelial cells (LECs). The mammalian target of rapamycin (mTOR) plays an important role in the growth and migration of LECs. In the current study, we used small interfering RNA (siRNA) to specifically attenuate mTOR in human lens epithelial B3 cells (HLE B3). We aimed to examine the effect of mTOR-siRNA on the proliferation, migration and epithelial-to-mesenchymal transition (EMT) of HLE B3 cells and explore the underlying mechanisms. The mTOR-siRNA was transfected into HLE B3 cells using lipofectamine 2000. The mRNA and protein levels of mTOR were examined to confirm the efficiency of mTOR-siRNA. The levels of mRNA and protein as well as the activity of mTOR down-stream effectors p70 ribosomal protein S6 kinase (p70S6K) and protein kinase B (PKB, AKT) were examined using real-time PCR or Western blot, respectively. The cell proliferation was determined using cell counting kit (CCK) 8 and cell growth curve assay. The cell migration was examined using Transwell system and Scratch assay. MTOR-siRNA effectively eliminated mTOR mRNA and protein. The proliferation and migration were significantly suppressed by mTOR-siRNA transfection. mTOR-siRNA reduced the mRNA of p70S6K and AKT in a time-dependent manner. Furthermore, the phosphorylation of p70S6K and AKT was decreased by mTOR-siRNA. MTOR-siRNA also eliminated the formation of mTORC1 and mTORC2 protein complex and blocked the transforming growth factor (TGF)-β-induced EMT. Our results suggested that mTOR-siRNA could effectively inhibit the proliferation, migration and EMT of HLE B3 cells through the inhibition of p70S6K and AKT. These results indicated that mTOR-siRNA might be an effective agent inhibiting HLE cells growth and EMT following cataract surgery and provide an alternative therapy for preventing PCO.

]]>
<![CDATA[Mutations of RagA GTPase in mTORC1 Pathway Are Associated with Autosomal Dominant Cataracts]]> https://www.researchpad.co/article/5989da6fab0ee8fa60b941cb

Cataracts are a significant public health problem with no proven methods for prevention. Discovery of novel disease mechanisms to delineate new therapeutic targets is of importance in cataract prevention and therapy. Herein, we report that mutations in the RagA GTPase (RRAGA), a key regulator of the mechanistic rapamycin complex 1 (mTORC1), are associated with autosomal dominant cataracts. We performed whole exome sequencing in a family with autosomal dominant juvenile-onset cataracts, and identified a novel p.Leu60Arg mutation in RRAGA that co-segregated with the disease, after filtering against the dbSNP database, and at least 123,000 control chromosomes from public and in-house exome databases. In a follow-up direct screening of RRAGA in another 22 families and 142 unrelated patients with congenital or juvenile-onset cataracts, RRAGA was found to be mutated in two unrelated patients (p.Leu60Arg and c.-16G>A respectively). Functional studies in human lens epithelial cells revealed that the RRAGA mutations exerted deleterious effects on mTORC1 signaling, including increased relocation of RRAGA to the lysosomes, up-regulated mTORC1 phosphorylation, down-regulated autophagy, altered cell growth or compromised promoter activity. These data indicate that the RRAGA mutations, associated with autosomal dominant cataracts, play a role in the disease by acting through disruption of mTORC1 signaling.

]]>
<![CDATA[Cataract surgery causes biomechanical alterations to the eye detectable by Corvis ST tonometry]]> https://www.researchpad.co/article/5989db4fab0ee8fa60bdbb29

Purpose

Modern cataract surgery is generally considered to bring about modest and sustained intraocular pressure (IOP) reduction. However, the pathophysiological mechanism for this remains unclear. Moreover, a change in ocular biomechanical properties after surgery can affect the measurement of IOP. The aim of the study is to investigate ocular biomechanics, before and following cataract surgery, using Corvis ST tonometry (CST).

Patients and methods

Fifty-nine eyes of 59 patients with cataract were analyzed. IOP with Goldmann applanation tonometry (IOP-G), axial length, corneal curvature and CST parameters were measured before cataract surgery and, up to 3 months, following surgery. Since CST parameters are closely related to IOP-G, linear modeling was carried out to investigate whether there was a change in CST measurements following cataract surgery, adjusted for a change in IOP-G.

Results

IOP-G significantly decreased after surgery (mean±standard deviation: 11.8±3.1 mmHg) compared to pre-surgery (15.2±4.3 mmHg, P<0.001). Peak distance (the distance between the two surrounding peaks of the cornea at the highest concavity), maximum deformation amplitude (the movement of the corneal apex from the start of deformation to the highest concavity) and A1/A2 velocity (the corneal velocity during inward or outward movement) significantly increased after cataract surgery (P<0.05) while radius (the central curvature radius at the highest concavity) was significantly smaller following cataract surgery (P<0.05). Linear modeling supported many of these findings, suggesting that peak distance, maximum deformation amplitude and A2 velocity were increased, whereas A2 deformation amplitude and highest concavity time were decreased (after adjustment for IOP change), following cataract surgery.

Conclusion

Corneal biomechanical properties, as measured with CST, were observed to change significantly following cataract surgery.

Trial registration

Japan Clinical Trials Registry UMIN000014370

]]>
<![CDATA[Effective cataract surgical coverage: An indicator for measuring quality-of-care in the context of Universal Health Coverage]]> https://www.researchpad.co/article/5989db4fab0ee8fa60bdbc14

Objective

To define and demonstrate effective cataract surgical coverage (eCSC), a candidate UHC indicator that combines a coverage measure (cataract surgical coverage, CSC) with quality (post-operative visual outcome).

Methods

All Rapid Assessment of Avoidable Blindness (RAAB) surveys with datasets on the online RAAB Repository on April 1 2016 were downloaded. The most recent study from each country was included. By country, cataract surgical outcome (CSOGood, 6/18 or better; CSOPoor, worse than 6/60), CSC (operated cataract as a proportion of operable plus operated cataract) and eCSC (operated cataract and a good outcome as a proportion of operable plus operated cataract) were calculated. The association between CSC and CSO was assessed by linear regression. Gender inequality in CSC and eCSC was calculated.

Findings

Datasets from 20 countries were included (2005–2013; 67,337 participants; 5,474 cataract surgeries). Median CSC was 53.7% (inter-quartile range[IQR] 46.1–66.6%), CSOGood was 58.9% (IQR 53.7–67.6%) and CSOPoor was 17.7% (IQR 11.3–21.1%). Coverage and quality of cataract surgery were moderately associated—every 1% CSC increase was associated with a 0.46% CSOGood increase and 0.28% CSOPoor decrease. Median eCSC was 36.7% (IQR 30.2–50.6%), approximately one-third lower than the median CSC. Women tended to fare worse than men, and gender inequality was slightly higher for eCSC (4.6% IQR 0.5–7.1%) than for CSC (median 2.3% IQR -1.5–11.6%).

Conclusion

eCSC allows monitoring of quality in conjunction with coverage of cataract surgery. In the surveys analysed, on average 36.7% of people who could benefit from cataract surgery had undergone surgery and obtained a good visual outcome.

]]>
<![CDATA[Individual Differences in Scotopic Visual Acuity and Contrast Sensitivity: Genetic and Non-Genetic Influences]]> https://www.researchpad.co/article/5989da72ab0ee8fa60b95305

Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision.

]]>
<![CDATA[Perioperative Antibiotics to Prevent Acute Endophthalmitis after Ophthalmic Surgery: A Systematic Review and Meta-Analysis]]> https://www.researchpad.co/article/5989dafbab0ee8fa60bc4873

Background

Post-operative endophthalmitis is a rare and dreaded complication in ophthalmic operations because it often induces irreparable vision loss. Although many ophthalmological studies aimed at reducing the rate of endophthalmitis have been performed around the world, controversy continues to surround some issues, including the choice of antimicrobials and their route of administration, duration and timing. The aim of this study is to investigate some of these unresolved issues.

Methods

A systematic review and meta-analysis of randomized controlled trials and observational studies was performed. The PubMed, EMBASE, Cochrane Library and Clinical Trials databases were searched to identify studies published until Feb. 2016. The relative risk (RR) for each clinical outcome data is presented with 95% confidence intervals (CIs). Pooled estimates of effects were calculated using random-effect models.

Results

Thirty-four studies from twenty-four reports involving 1264797 eyes were included in this analysis. Endophthalmitis occurred, on average, in one out of 6177 eyes when intracameral vancomycin/moxifloxacin were used and in one out of 1517 eyes when intracameral vancomycin/moxifloxacin were not used. The relative risk (95% CI) of endophthalmitis was reduced to 0.20 (0.10, 0.42) when intracameral antibiotics were used (p<0.0001). The subconjunctival injection of antibiotics was not superior to other administration routes included in this study (RR = 1.67, 95% CI (0.55, 5.05), p = 0.36). A statistically significant difference was found in the rate of endophthalmitis between the use and lack of use of topical antibiotics (RR = 0.65, 95% CI (0.43, 0.99), p = 0.04). However, no statistically significant difference was found in microbial isolation rates between these groups (RR = 0.77, 95% CI (0.34, 1.75), p = 0.53). When long-term and short-term use of topical antibiotics before surgery were compared, a statistically significant difference was found in microbial isolation rates (RR = 0.57, 95% CI (0.44, 0.74), p<0.0001).

Conclusions

This meta-analysis concluded intracameral antibiotics are effective at preventing endophthalmitis in ocular surgery. A randomized controlled trial confirms the efficacy of cefuroxime but recent large cohort studies support the efficacy of vancomycin/moxifloxacin intracamerally. Intracameral antibitoics are superior to subconjunctival injections but that irrigation antibitoic data are not of enough quality to make a comparison. Different results were found in two clinical outcomes between the use or lack of use of topical antibiotic therapy, we did not find sufficient evidence to conclude that its use prevents endophthalmitis.

]]>