Global prevalence and economic and humanistic burden of astigmatism in cataract patients: a systematic literature review

Screening for multifocal intraocular lens implantation in cataract patients in a public hospital

PURPOSE

To identify the rate and characteristics of cataract surgery candidates suitable for multifocal intraocular lens implantation among patients undergoing preoperative evaluation in a public hospital.

MATERIALS AND METHODS

Screening was performed based on the patient's medical records, comprehensive ophthalmic examination, optical biometry (Zeiss, IOL Master 700) and optical coherence tomography (OCT) (Heidelberg, OCT Spectralis) in accordance with the relevant indications and contraindications mentioned in the pertinent literature. Patients were included in the present study if they were eligible for bilateral cataract surgery. The exclusion criteria were the presence of central nervous system or motility issues, prior refractive surgery, the presence of astigmatism greater than 1 dioptre and/or the presence of important ocular comorbidities in either eye.

RESULTS

The study evaluated 1200 consecutive patients. Four hundred thirty-two patients (36%) were not eligible for bilateral surgery and were excluded from the study. Of the 768 patients included in the present study, 346 (45.1%) were considered suitable candidates. Four hundred twenty-two patients (54.9%) were excluded for one or both eyes. Among them, 121 (28.7%) were excluded because of retinal disease, 120 (28.4%) because of regular astigmatism (> 1.0 D of corneal astigmatism), 32 (7.5%) because of pseudoexfoliation or zonular instability, and 30 (7.1%) because of glaucoma or ocular hypertension; in addition, 90 (21.3%) patients were excluded for multiple reasons. Suitable candidates were significantly younger (70 and 75 years, respectively) (p < 0.001). After being informed about the potential risks and benefits of MOIL implantation, 212 of 346 (83.8%) eligible patients provided consent.

CONCLUSION

Close to half of cataract patients in a public hospital were eligible for MOIL implantation, and the majority of patients would proceed to surgery. The most prevalent contraindication was macular disease.

Comprehensive analysis of the miRNA-mRNA regulatory network involved in spontaneous recovery of an H2O2-induced zebrafish cataract model

OBJECTIVE

To identify the hub miRNAs and mRNAs contributing to the spontaneous recovery of an H2O2-induced zebrafish cataract model.

METHODS

Zebrafishes were divided into three groups, i.e., Group A, which included normal control fish (day 0), and Groups B and C, where fish were injected with 2.5% hydrogen peroxide into the anterior chamber and reared for 14 and 30 days, respectively. Fish eyes were examined by stereomicroscope photography and optical coherence tomography (OCT). RNA profiles of fish lenses were detected by RNA sequencing. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmiRs) were identified among three groups. The DEGs and DEmiRs, which changed in opposite positions between "B vs. A" and "C vs. B" were defined as ODGs (opposite positions changed DEGs) and ODmiRs (opposite positions changed DEmiRs). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analysis were carried out by R language. The protein-protein interaction network (PPI) was constructed using STRING. Potential targets of miRNAs were obtained using miRanda. miRNA-mRNA networks were constructed by Cytoscape.

RESULTS

The fish lens opacity formed on day 14 and recovered to transparent on day 30 after injection. Compared to group B, 1366 DEGs and 54 DEmiRs were identified in group C. "C vs. B" DEGs were enriched in gene clusters related to development and oxidative phosphorylation. Target genes of DEmiRs were enriched in clusters such as development and cysteine metabolism. Among three groups, 786 ODGs and 27 ODmiRs were identified, and 480 ODGs were predicted as targets of ODmiRs. Target ODGs were enriched in pathways related to methionine metabolism, ubiquitin, sensory system development, and structural constituents of the eye lens. In addition, we established an ODmiRs-ODGs regulation network.

CONCLUSION

We identified several hub mRNAs and altered miRNAs in the formation and reversal of zebrafish cataracts. These hub miRNAs/mRNAs could be potential targets for the non-surgical treatment of ARC.

Symmetrical femtosecond laser arc incision in correcting corneal astigmatism in cataract patients

AIM

To evaluate the effect of symmetrical arc incision correcting corneal astigmatism in femtosecond laser-assisted phacoemulsification (FLACS).

METHODS

This study enrolled patients with cataract combined with regular corneal astigmatism of >0.75 D, who underwent FLACS. Symmetrical arc incision was set at 8 mm diameter and 85% depth. The follow-up time was 3-24mo (4.92±3.49mo). Pentacam recorded the corneal astigmatism and higher-order aberration at pre-operation and post-operation. The changes in corneal astigmatism were analyzed by Alpins method. The correlation of astigmatism type, age, corneal horizontal diameter, corneal thickness, arc incision length, and correction index (CI) was analyzed, and the residual corneal astigmatism was compared with the residual whole eye astigmatism.

RESULTS

Totally 79 patients (102 eyes) were enrolled, 10 patients had corneal epithelial injury, 1 patient occurred corneal epithelial hyperplasia. The corneal astigmatism was 1.23±0.38 D pre-operation, and decreased to 0.76±0.39 D post-operation (t=10.146, P=0.000). Corneal high-order aberration was 0.17±0.08 µm pre-operation and 0.24±0.11 µm post-operation (t=-5.186, P=0.000). The residual corneal astigmatism and residual whole eye astigmatism were no significant difference (t=-0.347, P=0.729). Using Alpin's method, the following were determined: target-induced astigmatism (TIA) =1.23±0.38 D, surgery-induced astigmatism (SIA) =0.77±0.45 D, difference vector (DV)=0.77±0.39 D, and CI=0.54±0.28. Age, astigmatism size, corneal horizontal diameter, corneal thickness, and arc incision length were not correlated with CI. The CI for against the rule astigmatism (ATR) was better than that for with the rule astigmatism (WTR; P=0.001).

CONCLUSION

Femtosecond laser-assisted astigmatic keratotomy has better CI of ATR, but increase higher-order corneal aberration. CI is not ideal, it's not a perfect choice if we pursue ideal correction effect.

Influence of decentration of plate-haptic toric intraocular lens on postoperative visual quality

BACKGROUND

To evaluate the influence of decentration of plate-haptic toric intraocular lens (IOLs) on visual quality.

METHODS

This study enrolled 78 eyes of 78 patients. Patients in group A were implanted with toric IOLs, and patients in group B were implanted with monofocal IOLs. All patients were divided into group A1 and B1 (decentration below 0.3 mm) and group A2 and B2 (decentration above 0.3 mm). The uncorrected distance visual acuity (UDVA), best corrected visual acuity (BCVA), modulation transfer function cutoff (MTF cutoff), objective scatter index (OSI), strehl ratio (SR), optical interference and patients' satisfaction were measured in different pupils at three months postoperatively. The associations between decentration and visual quality were analyzed by Spearman correlation.

RESULTS

There were no significant differences in UDVA, BCVA, MTF cutoff, OSI, SR, optical interference and patients' satisfaction among subgroups. The differences in decentration between groups A and B were not statistically significant. In group A2, the total higher order aberrations (tHOAs) at pupil sizes of 3 mm (P = 0.046), 5 mm (P = 0.014), spherical aberrations at pupil sizes of 3 mm (P = 0.011), 4 mm (P = 0.014), 5 mm (P = 0.000), secondary astigmatism at pupil sizes of 3 mm (P = 0.002), 4 mm (P = 0.005) were higher than in group B2. Compared to group A1, group A2 had higher spherical aberrations at pupil sizes of 4 mm (P = 0.042), 5 mm (P = 0.001), 6 mm (P = 0.038), secondary astigmatism at pupil sizes of 3 mm (P = 0.013), 4 mm (P = 0.005), 6 mm (P = 0.013). Group B2 has higher coma and secondary astigmatism than group B1 at 6-mm pupil (P = 0.014, P = 0.045). Significant positive correlations were found between spherical aberrations and the decentration of group A1 and A2 at 6-mm pupils.

CONCLUSION

The decentration above 0.3 mm negatively affected visual quality due to increased tHOAs, spherical aberrations, coma and secondary astigmatism aberrations, the influence become larger with increasing pupil diameter. And toric IOLs are more affected by decentration than monofocal IOLs.

Long non-coding RNA nuclear paraspeckle assembly transcript 1 downregulation protects lens epithelial cells from oxidative stress-induced apoptosis by regulating the microRNA-124-3p/death-associated protein kinase 1 axis in age-related cataract

Oxidative stress plays a significant role in cataract development. It causes the apoptosis of lens epithelial cells (LECs), resulting in lens opacification and accelerating cataract progression. Long non-coding RNAs (lncRNAs) and microRNAs have been linked to cataract development. Notably, lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) is involved in LEC apoptosis and cataract formation. However, the molecular mechanism by which NEAT1 causes age-related cataracts remains unknown. In this study, LECs (SRA01/04) were exposed to 200 μM H₂O2 to generate an in vitro cataract model. The apoptosis and viability of cells were determined using flow cytometry and 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assays, respectively. Additionally, western blotting and quantitative polymerase chain reaction were used to determine the miRNA and lncRNA expression levels. When LECs were treated with hydrogen peroxide, lncRNA NEAT1 expression levels were significantly upregulated, which contributed to LEC apoptosis. Notably, lncRNA NEAT1 suppressed the expression of miR-124-3p, a critical regulator of apoptosis, whereas NEAT1 inhibition increased miR-124-3p expression and alleviated apoptosis. However, this effect was reversed when miR1243p expression was inhibited. Additionally, the miR1243p mimic effectively inhibited the death-associated protein kinase 1 (DAPK1) expression and apoptosis of LECs, while the DAPK1 mimic reversed these effects. In conclusion, our findings indicate that the lncRNA NEAT1/miR-124-3p/DAPK1 signaling loop is involved in the regulation of LEC apoptosis induced by oxidative stress, which can be exploited to develop potential treatment strategies for age-related cataracts.

Epidemiology and Burden of Astigmatism: A Systematic Literature Review

SIGNIFICANCE

This is the first literature review to report the epidemiology, patient burden, and economic burden of astigmatism in the general adult population. The unmet needs of astigmatism patients with coexisting ocular conditions (cataract, glaucoma, dry eye, presbyopia, or macular degeneration) and risks associated with untreated astigmatism are also reviewed and reported.

PURPOSE

This study aimed to identify, report, and summarize the published literature on epidemiology, patient burden, and economic burden of astigmatism using a systematic literature review.

METHODS

MEDLINE, EMBASE, and Cochrane Library databases were searched (January 1996 to May 2021). Search results were limited to the English language. Proceedings (2018 to 2021) from ophthalmology congresses were searched along with gray literature using the Google Scholar platform.

RESULTS

The literature search yielded 6804 citations, of which 125 met the inclusion criteria (epidemiology, 68; patient burden, 60; economic burden, 6). Astigmatism prevalence in the general population varied from 8 to 62%, with higher rates in individuals 70 years or older. The prevalence of with-the-rule astigmatism was higher in individuals 40 years or younger, whereas rates of against-the-rule and oblique astigmatism increased with age. Astigmatic patients experienced decreased vision quality, increased glare (53 to 77%), haloes (28 to 80%), night-time driving difficulties (66%), falls, and spectacle dependence (45 to 85%). Astigmatic patients performed vision-related tasks slower (1 D, 9% slower; 2 D, 29% slower) and made more errors (1 D, 38% more errors; 2 D, 370% more errors) compared with fully corrected individuals. In cataract patients with astigmatism, the annual mean per-patient productivity loss costs ranged from €55 ($71) to €84 ($108), and mean informal care costs ranged from €30 ($39) to €55 ($71) with a mean of 2.3 to 4.1 hours spent on informal care.

CONCLUSIONS

Uncorrected astigmatism decreases patients' vision-related quality of life, decreases productivity among working-age adults, and poses an economic burden on patients and their families.

Accuracy of the LaserArcs Femtosecond Cataract Surgery Arcuate Incision Nomogram in Patients Undergoing Cataract Surgery and Astigmatism Reduction

Purpose

The purpose of this study is to evaluate the efficacy and safety of the laserarcs.com nomogram in reducing astigmatism among cataract patients that underwent astigmatism reduction with laser arcuate incisions.

Methods

In this retrospective study, 50 patients who underwent uncomplicated cataract surgery with laser arc incisions for the reduction of astigmatism with a single surgeon between the dates of January 23, 2021 and February 10, 2022 were evaluated in a single eye. Preoperative astigmatism was determined on the basis of keratometry from biometry (IOLmaster, Carl Zeiss Meditec or LenStar LS900, Haag-Streit, Bern, Switzerland) and was compared to the postoperative manifest astigmatism. The percent change in the absolute magnitude of astigmatism was calculated along with the percent of patients with various levels of postoperative astigmatism.

Results

Mean cylinder was 0.97 ± 0.49 D pre-op and 0.21 ± 0.28 D postop. Mean reduction in cylinder was 81.4 ± 47.7% (P < 0.00001, one-sample t-test compared to a hypothetical 60% reduction in cylinder). Residual cylinder was ≤0.5 D in 90%, 0.25 D in 72%, and 0 D in 58%. Postoperative uncorrected visual acuity was 20/30 or better in 92% and 20/20 or better in 40%. Subgroup analysis showed that residual astigmatism was not affected by patient age, magnitude of preoperative astigmatism, preoperative spherical equivalent, or corneal curvature. No adverse events related to the laser arcuate incisions were noted.

Conclusion

Use of the LaserArcs nomogram yielded a significant reduction in preoperative astigmatism. Postoperative uncorrected visual acuity was substantially similar to best-corrected visual acuity, suggesting that many patients undergoing treatment will function without correction for distance tasks.

Advances in drug therapy and delivery for cataract treatment

PURPOSE OF REVIEW

Cataract is one of the leading causes of blindness worldwide and surgery is the only available treatment. Pharmacological therapy has emerged as a potential approach to combat the global shortage of surgery due to a lack of access and resources. This review summarizes recent findings in pharmacological treatment and delivery, focusing on drugs that target oxidative stress and the aggregation of crystallins.

RECENT FINDINGS

Antioxidants and oxysterols have been shown to improve or reverse lens opacity in cataract models. N-acetylcysteine amide and N-acetylcarnosine are two compounds that have increased bioavailability over their precursors, alleviating the challenges that have come with topical administration. Studies have shown promising results, with topical N-acetylcarnosine clinically decreasing lens opacity. Furthermore, lanosterol, and more recently 5-cholesten-3b,25-diol (VP1-001), have been reported to combat the aggregation of crystallins in vivo and ex vivo . Delivery has improved with the use of nanotechnology, but further research is needed to solidify these compounds' therapeutic effects on cataracts and improve delivery methods to the lens.

SUMMARY

Although further research in drug dosage, delivery, and mechanisms will need to be conducted, pharmacologic therapies have provided new strategies and treatments for the reversal of cataracts.

Post-Market Evaluation of Rotational Stability and Visual Performance of a New Toric Intraocular Lens with Frosted Haptics

PURPOSE

To evaluate 3-month rotational stability, and visual and refractive outcomes of a toric intraocular lens (IOL) with frosted haptics.

PATIENTS AND METHODS

A post-market, prospective, multi-center, single-arm, open-label study conducted at seven clinical sites in the United States. Two hundred and two eyes of 133 subjects with unilateral or bilateral cataracts and corneal astigmatism were implanted with the Tecnis Toric II IOL, Models ZCU150 to 600 (Johnson & Johnson Surgical Vision, Inc.). Lens axis misalignment/rotation, visual acuity, manifest refraction, and surgeon and patient satisfaction were evaluated 3 months postoperatively. Lens rotation was determined with operative and postoperative visit photographs and was analyzed by two independent masked analysts.

RESULTS

Mean absolute lens rotation was 0.82° ± 1.00° and 0.94° ± 0.71° at 1 day (n = 189 eyes) and 3 months (n = 185 eyes), respectively. Absolute lens rotation was ≤5° in 98.9% and 100% of eyes at 1 day and 3 months, respectively. At 3 months, postoperative monocular uncorrected and corrected distance visual acuities were 0.004 ± 0.115 LogMAR (20/20) and -0.066 ± 0.092 LogMAR (20/17), mean spherical equivalent was -0.25 D ± 0.35 D and residual refractive cylinder was +0.27 D ± 0.33 D. Surgeons were satisfied/very satisfied with overall clinical outcomes and rotational stability in 99% of eyes, and with uncorrected distance vision in 98.5% of eyes.

CONCLUSION

The study results demonstrate that the Tecnis Toric II IOL has excellent rotational stability with a high percentage of study eyes being within 5° of intended orientation. The study lens demonstrated excellent uncorrected distance visual acuity, reduction of cylinder, and exceptional patient and surgeon satisfaction.

Astigmatism profile in the elderly population: Tehran Geriatric Eye Study

PURPOSE

To determine the prevalence of astigmatism and its associated factors and examine astigmatism symmetry patterns in an elderly population.

STUDY DESIGN

Population based cross-sectional study.

METHODS

The present population-based cross-sectional study was conducted on an elderly population above 60 years of age in Tehran, Iran in 2019. The sampling was done using the stratified multistage random cluster sampling method. All study participants underwent a complete optometric examination and slit-lamp biomicroscopy.

RESULTS

The prevalence of astigmatism higher than -0.50, -1.00, and -2.00 D was 83% (95% CI: 81 -84), 52 % (95% CI: 50 -54), and 19% (95% CI: 17-20), respectively. These prevalence was 79%(95% CI: 77-81), 46(95% CI: 44-49) and 14(95% CI: 13-16) in subjects without a history of ocular surgery, respectively. Based on cylinder power worse than -1.00 D, 10% (95% CI: 9-12), 20% (95% CI: 18-22), and 21% (95% CI:19-23) of study participants had with the rule, against the rule, and oblique astigmatism, respectively. According to the results of the multiple regression model, male gender, older age, low education level, pure posterior subcapsular cataract, pseudophakia, and myopia were independent factors associated with astigmatism. The prevalence of anisorule astigmatism was 57 % (95% CI: 56-59), the most common anisorule astigmatism was against the rule-oblique type with a prevalence of 36% (95% CI: 34-38).

CONCLUSION

The prevalence of astigmatism was high in the elderly population of Tehran. More than half of the participants in this study had anisorule astigmatism, and against the rule-oblique combination was more prevalent than other types. A posterior subcapsular cataract, a history of cataract surgery, and myopia were the associated factors of astigmatism in this study.

Agreement Between Two Swept-source Optical Coherence Tomography Biometers and A Partial Coherence Interferometer

Purpose

To evaluate the level of agreement between ANTERION (Heidelberg Engineering, Heidelberg, Germany), OA-2000 (Tomey, Nagoya, Japan), and IOLMaster 500 (Carl Zeiss AG, Jena, Germany).

Methods

Fifty-one eyes of 51 patients were included in the study. Flat keratometry (K) and steep K, vector component of astigmatism (Jackson cross-cylinder at 0° and 90° [J₀] and Jackson cross-cylinder at 45° and 135° [J₄₅]), anterior chamber depth, and axial length were compared using the three devices. Repeated measures analysis of variance was conducted to compare the mean values of the biometrics. Pearson correlation test was conducted to analyze the correlations of the measured values, and a Bland-Altman plot was used to assess the agreement between the three devices. The predicted intraocular lens power of each device was compared to the others using the SRK/T, Haigis, Barrett Universal II, and Kane formulas.

Results

All K values measured using ANTERION were flatter than those of other instruments. However, good agreement was observed for flat K (ANTERION - OA-2000; 95% limits of agreement [LoA], 0.86 diopters [D]) and steep K (ANTERION - OA-2000; 95% LoA, 0.93 D) and OA-2000 - IOLMaster 500 (95% LoA, 0.93 D). J₀ and J₄₅ vector components of astigmatism were not statistically different; however, the agreements were poor between the devices (95% LoA ≥1.97 D). Anterior chamber depth values of ANTERION and OA-2000 were interchangeable (95% LoA, 0.15 mm). The axial length showed a high agreement (95% LoA ≤0.17 mm) among the three devices. The predicted intraocular lens powers of the three devices were not interchangeable regardless of formulas (95% LoA ≥1.04 D).

Conclusions

Significant differences in ocular biometrics were observed between ANTERION and the other two devices. This study demonstrated that only axial length showed good agreement among devices.

Dioptric power and refractive behaviour: a review of methods and applications

Myopia is a global healthcare concern and effective analyses of dioptric power are important in evaluating potential treatments involving surgery, orthokeratology, drugs such as low-dose (0.05%) atropine and gene therapy. This paper considers issues of concern when analysing refractive state such as data normality, transformations, outliers and anisometropia. A brief review of methods for analysing and representing dioptric power is included but the emphasis is on the optimal approach to understanding refractive state (and its variation) in addressing pertinent clinical and research questions.

Although there have been significant improvements in the analysis of refractive state, areas for critical consideration remain and the use of power matrices as opposed to power vectors is one such area. Another is effective identification of outliers in refractive data. The type of multivariate distribution present with samples of dioptric power is often not considered. Similarly, transformations of samples (of dioptric power) towards normality and the effects of such transformations are not thoroughly explored. These areas (outliers, normality and transformations) need further investigation for greater efficacy and proper inferences regarding refractive error. Although power vectors are better known, power matrices are accentuated herein due to potential advantages for statistical analyses of dioptric power such as greater simplicity, completeness, and improved facility for quantitative and graphical representation of refractive state.

Real-world incidence of monofocal toric intraocular lens repositioning: analysis of the American Academy of Ophthalmology IRIS Registry

PURPOSE

To determine the 12-month incidence of reoperation to realign 2 commercially available types of implanted monofocal toric acrylic intraocular lenses (IOLs).

SETTING

American Academy of Ophthalmology IRIS (Intelligent Research in Sight) Registry.

DESIGN

Registry retrospective study.

METHODS

Eyes that underwent cataract extraction and were implanted with a TECNIS or AcrySof monofocal toric IOL in 2016 and 2017 were identified. The rate of reoperation for IOL realignment (Current Procedural Terminology code 66825) within 365 days of implantation was determined for each IOL group. Risk factors for repositioning were evaluated using logistic regression modeling.

RESULTS

A total of 6482 eyes were implanted with a monofocal toric IOL, including 2013 (31.06%) with a TECNIS and 4469 (68.94%) with an AcrySof IOL. During the first postoperative year, 87 (1.3%) eyes underwent surgical IOL repositioning. The incidence of repositioning was significantly higher (P < .0001) for TECNIS-implanted (3.1%, 62/2013) than for AcrySof-implanted (0.6%, 25/4469) eyes (odds ratio [OR] 5.6; 95% CI, 3.5-8.9). Younger age (OR 0.76; 95% CI, 0.67-0.86 per 5-year increase) was associated with a higher risk for IOL repositioning.

CONCLUSIONS

Real-world analysis of U.S. patients in the IRIS Registry revealed that the rate of surgical IOL repositioning was 5 times higher in eyes implanted with TECNIS than with AcrySof monofocal toric IOLs for astigmatic correction at the time of cataract surgery. These findings should be considered when selecting a toric IOL for correction of astigmatism in cataract patients, particularly in younger patients with a higher risk for misalignment requiring repositioning.

Adiposity by Differing Measures and the Risk of Cataract in the UK Biobank: The Importance of Diabetes

Purpose

To examine the association between adiposity by differing measures and incident cataract and identify important factors contributing to the association.

Methods

Our analysis included 153,139 adults from the UK Biobank, aged 40 to 70 years at baseline (2006-2010). Cataract was ascertained using hospital inpatient, and self-reported data until the early of 2021. Anthropometric measures, body fat percentage, and glycosylated hemoglobin (HbA1c) were measured at baseline.

Results

During a median follow-up of 10.9 years, 15,255 cases of incident cataract were documented. HbA1c was an important contributor to the association between obesity and incident cataract. Obesity; defined by body mass index was associated with an increased risk of cataract (hazard ratio [HR], 1.21 95% confidence interval [CI], 1.16-1.26), and this association was attenuated but remained significant after additional adjustment for HbA1c (HR, 1.05; 95% CI, 1.00-1.10). Similar results were observed for obesity defined by waist circumference or waist-to-hip ratio. Obesity defined by fat percentage was associated with an increased risk of cataract before but not after adjustment for covariates. The association between obesity defined by body mass index and incident cataract was positively significant in individuals with normal HbA1c (HR, 1.07; 95% CI, 1.02-1.13), but inversely significant in those with prediabetes (HR, 0.80; 95% CI, 0.67-0.96) or diabetes (HR, 0.74; 95% CI, 0.61-0.89).

Conclusions

Anthropometric measurements are more predictive of cataract than bioelectrical impedance measures. Diabetes plays an important role in the association between obesity and incident cataract.

Socio-economic disparity in visual impairment from cataract

AIM

To investigate the association of visual impairment from cataract with human development index (HDI) by years lived with disability (YLDs).

METHODS

Published data on national age-standardized YLD rates caused by cataract and national HDIs in 2019 were obtained. Age-standardized YLD rates from 1990 to 2019 were analyzed to explore cataract burden among patients with different income levels. Age-standardized YLD rates in different HDI groups were compared by different degrees of visual impairment. Association between national age-standardized YLD rates and HDI in 2019 was analyzed.

RESULTS

The age-standardized YLD rates of populations with visual impairment or blindness due to cataract declined from 1990 to 2019, especially among those with lower middle income. Multiple comparison tests revealed that countries with low HDI had significantly higher age-standardized YLD rates of blindness due to cataract than those with high and very high HDI (P<0.001). The age-standardized YLD rates of populations with blindness (β=-0.588, P<0.001), severe vision loss (β=-0.378, P<0.001), and moderate vision loss (β=-0.389, P<0.001) inversely correlated with HDI.

CONCLUSION

Age-standardized YLD rates caused by cataract have declined since 1990. The burden of visual impairment due to cataract inversely correlate with national socioeconomic development and is more concentrated in countries with low HDI than those with high HDI, especially among the blind. These findings highlight the need to provide additional cataract services and cataract surgery coverage to developing countries to decrease the burden of avoidable blindness caused by cataract.

Calculation of Toric Intraocular Lens Power with the Barrett Calculator and Data from Three Keratometers

Aim

To investigate the interdevice agreement for differences in toric power calculated using data on anterior corneal astigmatism obtained with corneal topography/ray-tracing aberrometry (iTrace), partial coherence interferometry (IOLMaster 500), and Scheimpflug imaging (Pentacam).

Methods

The analysis included 101 eyes (101 subjects) with regular astigmatism. The main outcome measures were corneal cylinder power, axis of astigmatism, and keratometry values. Toricity and toric IOL power were calculated using the online Barrett toric calculator. Interdevice agreement for measurement and calculation was assessed using a paired sample t-test and a nonparametric test.

Results

Significant interdevice differences were noted in the magnitude of astigmatism and flat, steep, and mean keratometry values between iTrace and IOLMaster (all P < 0.01); in flat, steep, and mean keratometry values (all P < 0.001) but not in the magnitude of astigmatism (P=0.325) between iTrace and Pentacam; and in the magnitude of astigmatism and steep and mean keratometry values (all P < 0.01) but not in flat keratometry values (P=0.310) between IOLMaster and Pentacam. The toric IOL power calculated using data from the three devices showed the following trend: iTrace > IOLMaster (0.49 ± 0.36, P < 0.001) and Pentacam (0.39 ± 0.42, P < 0.001) and Pentacam was <IOLMaster (-0.10 ± 0.39, P=0.009). There were differences in toricity calculated using data from the three devices (P=0.004).

Conclusions

Differences in toric IOL power and toricity calculated using anterior keratometry data from iTrace, IOLMaster 500, and Pentacam should be noted in clinical practice.

Innovative trifocal (quadrifocal) presbyopia-correcting IOLs: 1-year outcomes from an international multicenter study

Trifocal IOLs provided an excellent safety profile with satisfactory patient outcomes for UDVA, DCIVA, and UNVA. Defocus curve demonstrated 20/25 Snellen or better visual acuity at near to intermediate distance.

Purpose:

To evaluate visual acuity (VA) and safety of the new AcrySof IQ PanOptix presbyopia-correcting IOL at 12 months postimplantation.

Setting:

Seventeen sites in Europe, Australia, and South America.

Design:

Prospective, single-arm, nonmasked, nonrandomized study.

Methods:

Of 167 patients enrolled, 149 received study IOLs in both eyes; 145 completed the study. Binocular uncorrected distance VA (UDVA; 4 m), monocular corrected distance VA (CDVA), binocular distance-corrected intermediate VA (DCIVA; 60 cm and 80 cm), binocular uncorrected near VA (UNVA; 40 cm), and binocular defocus curves were evaluated. Safety was assessed by monitoring adverse events (AEs).

Results:

Of 149 patients, 92 patients (62%) were women and 139 patients (93%) were white; mean ± SD age was 68.9 ± 9.3 years. At 12 months, mean binocular UDVA was 0.02 ± 0.11 logarithm of the minimum angle of resolution (logMAR); monocular CDVA was 0.01 ± 0.13 logMAR (first eye) and 0.01 ± 0.10 logMAR (second eye); binocular DCIVA was 0.04 ± 0.12 logMAR and 0.08 ± 0.14 logMAR at 60 cm and 80 cm, respectively; and binocular UNVA was 0.07 ± 0.11 logMAR. At 6 months, mean binocular defocus curve VA (0.00 diopter [D] to −3.00 D) ranged from −0.04 to 0.13 logMAR. Binocular VA at distance (0.00 D), intermediate (−1.50 D), and near (−2.50 D) was −0.04 ± 0.11 logMAR, 0.07 ± 0.13 logMAR, and 0.07 ± 0.13 logMAR, respectively. Serious ocular AE rates were 1.4% or less in first and second eyes. Posterior capsulotomy rates were 3.4% (first eye) and 2.7% (second eye).

Conclusions:

The study IOL provided good VA outcomes. Defocus curve showed VA of 20/25 Snellen or better from near to intermediate distance. Rates of serious and nonserious AEs were low.

Lanosterol reduces the aggregation propensity of ultraviolet-damaged human γD-crystallins: a molecular dynamics study

Ultraviolet (UV) radiation-induced oxidation of tryptophan (Trp) to kynurenine (KN) (TRP > KN) in human γD-crystallins (HγD-Crys) promotes the conversion of proteins into partially unfolded species that act as important precursors for sequential large-scale aggregation. Herein, we report that lanosterol shows protective activity to the structure of the TRP > KN mutant HγD-Crys, particularly its N-terminal domain (N-td), by using all-atom molecular dynamics simulations. The Trp68 > KN mutation significantly destabilizes the originally highly stable "Tyr55-Trp68-Tyr62" cluster, thereby causing loop2, where the mutation occurs, to become very flexible. The large fluctuation of loop2 induces cracks, which appear on the protein surface, resulting in the intrusion of water molecules into the hydrophobic core of the N-td. This event eventually triggers the unfolding of the N-td. However, lanosterol can suppress the large fluctuation of loop2 to protect the structural stability of the mutant N-td, thus reducing the aggregation propensity of the TRP > KN mutant HγD-Crys. This structure protective activity of lanosterol arises from its capability to preferentially bind to the hydrophobic regions near loop2. Thus, lanosterol acts as a "water blocker" to prevent the invasion of solvent molecules into the hydrophobic core. These findings provide some valuable insights into the development of potential lanosterol-based drugs for cataract prevention and treatment.

Effect of defocus combined with rotation on the optical performance of trifocal toric IOLs

PURPOSE

To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced.

METHODS

This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D).

RESULTS

The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively.

CONCLUSION

For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

Effect of femtosecond laser-assisted steepest-meridian clear corneal incisions on preexisting corneal regular astigmatism at the time of cataract surgery

AIM

To investigate the clinical efficacy and safety of femtosecond laser-assisted steepest-meridian clear corneal incisions for correcting preexisting corneal astigmatism performed at the time of cataract surgery.

METHODS

This prospective case series study comprised consecutive age-related cataract patients with corneal regular astigmatism (range: +0.75 to +2.50 D) who had femtosecond laser-assisted steepest-meridian clear corneal incisions (single or paired). Corneal astigmatism was performed with the Pentacam preoperatively and 3mo postoperatively. Total corneal astigmatism and steepest-meridian measured in the 3-mm central zone were used to guide the location, size and number of clear corneal incision. The vector analysis of astigmatic change was performed using the Alpins method.

RESULTS

Totally 138 eyes of 138 patients were included. The mean preoperative corneal astigmatism was 1.31±0.41 D, and was significantly reduced to 0.69±0.34 D (equivalent to difference vector) after surgery (P<0.01). The surgically-induced astigmatism was 1.02±0.54 D. The correction index (ratio of target induced astigmatism and surgically-induced astigmatism: 0.72±0.36) as well as the magnitude of error (difference between surgically-induced astigmatism and target induced astigmatism: -0.29±0.51) represented a slight under correction. For angle of error, the arithmetic mean was 1.11±13.70, indicating no significant systematic alignment errors.

CONCLUSION

Femtosecond-assisted steepest-meridian clear corneal incision is a fast, customizable, adjustable, precise, and safe technique for the reduction of low to moderate corneal astigmatism during cataract surgery.

Long non-coding RNA nuclear paraspeckle assembly transcript 1 protects human lens epithelial cells against H2O2 stimuli through the nuclear factor kappa b/p65 and p38/mitogen-activated protein kinase axis

Background

Long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) plays a regulatory role in many biological processes; however, its role in cataracts has yet to be illuminated. This study aimed to investigate the protective role of NEAT1 in hydrogen peroxide (H₂O₂)-treated human lens epithelial cells (HLECs) and its underlying molecular mechanism.

Methods

HLECs (SRA01/04) were treated with 300 µM H₂O₂ to mimic cataract in vitro. Cell viability was detected by performing an MTT assay and EdU staining. Flow cytometry was carried out to detect apoptosis of HLECs. DNA damage was examined using γ-H2A histone family member X staining. and reactive oxygen species (ROS) production was measured using 2’,7’dichlorofluorescin diacetate staining. The expression levels of lncRNA and proteins were detected with quantitative real-time polymerase chain reaction and western blot, respectively.

Results

The expression of NEAT1 was observed to be increased in H₂O₂-treated HLECs and age-related cataract (ARC) tissues. Knockdown NEAT1 strongly protected against H₂O₂-induced cell death and also regulated the expression of cleaved caspase-3, B-cell lymphoma 2, and Bcl-2-associated X protein. Further, knockdown NEAT1 also significantly suppressed H₂O₂-induced intracellular ROS production and malondialdehyde (MDA) content, but elevated the glutathione (GSH) activity of H₂O₂-treated cells. Also, it is demonstrated that si-NEAT1 greatly inhibited H₂O₂-induced phosphorylation of NF-кB p65 and p38 MAPK.

Conclusions

This study confirmed that knockdown NEAT1 attenuated H₂O₂-induced damage in HLECs, and inhibited the oxidative stress and apoptosis of HLECs via regulating nuclear factor-kappa B (NF-κB) p65 and p38 MAPK signaling. It may provide a potential target for clinical treatment of cataracts.

Association between extreme heat and hospital admissions for cataract patients in Hefei, China

Cataract is the first cause of blindness and the major cause of visual impairment worldwide. Under conditions of global warming, researchers have begun to give attention to the influence of increasing temperature on cataract patients. Our paper aimed to investigate the association between extreme heat and hospital admissions for cataract in Hefei, China. Based on data from the New Rural Cooperative Medical System and National Meteorological Information Center, we used a generalized additive model and a distributed lag nonlinear model to examine the relationship between extreme heat and hospitalizations for cataract, with consideration of cumulative and lagged effects. When current mean temperature was above 28 °C, each 1 °C rise was associated with a 4% decrease in the number of cataract admissions (RR = 0.96, 95% CI = 0.94-0.98). The cumulative relative risk over 11 days of lag was the lowest, which indicated that every 1 °C increase in mean temperature above 28 °C was associated with a 19% decrease in the number of hospital admissions for cataract (RR = 0.81, 95% CI = 0.75-0.88). In subgroup analyses, the negative association between extreme heat and hospital admissions for cataract was stronger among patients who were not admitted to provincial-level hospitals. In conclusion, this paper found that extreme heat was negatively associated with cataract hospitalizations in Hefei, providing useful information for hospitals and policymakers.

Management of Cataract in Patients with Irregular Astigmatism with Regular Central Component by Phacoemulsification Combined with Toric Intraocular Lens Implantation

Purpose

To evaluate visual acuity (VA) and refractive status in patients with cataract and irregular astigmatism with a regular central component after phacoemulsification with implantation of a toric intraocular lens (IOL).

Methods

Patients with cataract associated with irregular astigmatism with a regular central component were enrolled. All patients underwent phacoemulsification and toric IOL implantation. Postoperative visual acuity, residual astigmatism, toric IOL rotation, higher-order aberration, and objective and subjective visual quality were measured 3 months after surgery.

Results

Twenty-three eyes were included in the study. The logMAR corrected and uncorrected distance visual acuity values were decreased at 3 months postoperatively (p  <  0.005). The preoperative average corneal astigmatism and postoperative residual astigmatism were 1.15–6.97 D (1.99 ± 1.26 D) and 0–2.75 D (0.65 ± 0.57 D), respectively. The average IOL rotation was 3.17 ± 2.01°. Some objective indicators of visual quality, including the modulation transfer function (p  <  0.05), Strehl ratio (p  <  0.005), 100% VA (p  <  0.005), 20% VA (p  <  0.005), and 9% VA (p  <  0.005), were significantly higher than the corresponding preoperative values. The objective scatter index (p  <  0.005) was significantly lower than that before surgery. The postoperative VF-14 scale score was 83.99 ± 14.58.

Conclusion

Toric IOL implantation has a good corrective effect on certain specific types of corneal irregular astigmatism with cataract. This effect can be attributed to its ability to correct the regular component of irregular astigmatism. The indications for toric IOL implantation could be expanded to some extent, thereby bringing benefit to more patients.

Long non-coding RNA ANRIL alleviates H2O2-induced injury by up-regulating microRNA-21 in human lens epithelial cells

The accurate role of ANRIL in cataract is poorly understood. We aimed to reveal the effects of ANRIL on H2O2-treated HLECs, SRA01/04, as well as the regulatory mechanisms. Oxidative stress model of HLECs was induced by H2O2. Cell injury was evaluated according to cell proliferation, apoptosis and DNA damage using CCK-8 assay/flow cytometry and TUNEL assays/γH2AX staining. Expressions of ANRIL and miR-21 in HLECs were determined by RT-qPCR. The effects of miR-21, miR-34a and miR-122-5p inhibition as well as AMPK and β-catenin on HLECs with ANRIL overexpression and H2O2 stimulation were analyzed. In vivo experiment was performed via RT-qPCR. H2O2 repressed proliferation and induced apoptosis or DNA damage in HLECs. Those alterations induced by H2O2 were attenuated by ANRIL overexpression. MiR-21 was positively regulated by ANRIL, and both of them were repressed in H2O2-induced HLECs and cataract patient tissues. Inhibition of miR-21 but not miR-34a or miR-122-5p reversed the effects of ANRIL on H2O2-treated HLECs. Phosphorylation of AMPK and expression of β-catenin were increased by ANRIL via regulating miR-21. AMPK and β-catenin affected beneficial function of ANRIL-miR-21 axis.Therefore, lncRNA ANRIL attenuated H2O2-induced cell injury in HELCs via up-regulating miR-21 via the activation of AMPK and β-catenin.

Toric intraocular lens versus limbal relaxing incisions for corneal astigmatism after phacoemulsification

BACKGROUND

Cataract is the leading cause of blindness in the world, and clinically significant astigmatism may affect up to approximately 20% of people undergoing cataract surgery. Pre-existing astigmatism in people undergoing cataract surgery may be treated, among other techniques, by placing corneal incisions near the limbus (limbal relaxing incisions or LRIs) or by toric intraocular lens (IOLs) specially designed to reduce or treat the effect of corneal astigmatism on unaided visual acuity.

OBJECTIVES

To assess the effects of toric IOLs compared with LRIs in the management of astigmatism during phacoemulsification cataract surgery.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register; 2019, Issue 9); Ovid MEDLINE; Ovid Embase and four other databases. The date of the search was 27 September 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing toric IOLs with LRIs during phacoemulsification cataract surgery.  DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. We graded the certainty of the evidence using GRADE. Our primary outcome was the proportion of participants with postoperative residual refractive astigmatism of less than 0.50 dioptres (D) six months or more after surgery. We also collected data on mean residual refractive astigmatism. Secondary outcomes included: uncorrected distance visual acuity, vision-related quality of life, spectacle independence and adverse effects including postoperative lens rotation requiring re-alignment. To supplement the main systematic review assessing the effects of toric IOLs compared with LRIs in the management of astigmatism during phacoemulsification cataract surgery, we sought to identify economic evaluations on the subject.

MAIN RESULTS

We identified 10 relevant studies including 517 people (626 eyes). These studies took place in China (three studies), UK (three), Brazil (one), India (one), Italy (one) and Spain (one). The median age of participants was 71 years. The level of corneal astigmatism specified in the inclusion criteria of these studies ranged from 0.75 D to 3 D. A variety of toric IOLs were used in these studies, in all but one study, these were monofocal. Studies used three different nomograms to determine the size and placement of the LRI. Two studies did not specify this. None of the studies were at low risk of bias in all domains, but two studies were at low risk of bias in all domains except selective outcome reporting, which was unclear. The remaining studies were at a mixture of low, unclear or high risk of bias. People receiving toric IOLs were probably more likely to achieve a postoperative residual refractive astigmatism of less than 0.5 D six months or more after surgery (risk ratio (RR) 1.40, 95% confidence interval (CI) 1.10 to 1.78; 5 RCTs, 262 eyes). We judged this to be moderate-certainty evidence, downgrading for risk of bias. In the included studies, approximately 500 eyes per 1000 achieved postoperative astigmatism less than 0.5 D in the LRI group compared with 700 per 1000 in the toric IOLs group. There was a small difference in residual astigmatism between the two groups, favouring toric IOLs (mean difference (MD) -0.32 D, 95% CI -0.48 to -0.15 D; 10 RCTs, 620 eyes). Although all studies favoured toric IOLs, the results of individual studies were inconsistent (range of effects -0.02 D to -0.71 D; I² = 89%). We considered this to be low-certainty evidence, downgrading for risk of bias and inconsistency. People receiving a toric IOL probably have a small improvement in visual acuity at six months or more after surgery compared to people receiving LRI, but the difference is small and probably clinically insignificant (MD -0.04 logMAR, 95% CI -0.07 to -0.02; 8 RCTs, 474 eyes; moderate-certainty evidence). Low-certainty evidence from one study of 40 people suggested little difference in vision-related quality of life measured using the Visual Function Index (VF-14) (MD -3.01, 95% CI -8.56 to 2.54). Two studies reported spectacle independence and suggested that people receiving toric IOLs may be more likely to be spectacle independent (RR 1.56, 95% CI 1.14 to 2.15; 100 people; low-certainty evidence). There were no cases of lens rotation requiring surgery (very low-certainty evidence). Five studies (320 eyes) commented on a range of other adverse effects including corneal oedema, endophthalmitis and corneal ectasia. All these studies reported that there were no adverse events with the exception of one study (40 eyes) where one participant in the LRI group had a central de-epithelisation which recovered over 10 days. We found no economic studies that compared toric IOLs with LRIs.

AUTHORS' CONCLUSIONS

Toric IOLs probably provide a higher chance of achieving astigmatism within 0.5 D after cataract surgery compared with LRIs. There may be a small mean difference in postoperative astigmatism, favouring toric IOLs, but this difference is likely to be clinically unimportant. There was no evidence of an important difference in postoperative visual acuity or quality of life between the techniques. Evidence on adverse effects was uncertain. The apparent shortage of relevant economic evaluations indicates that economic evidence regarding the costs and consequence of these two procedures is currently lacking.

Refractive and Visual Outcomes and Rotational Stability of Toric Intraocular Lenses in Eyes With and Without Previous Ocular Surgeries: A Longitudinal Study

PURPOSE

To evaluate visual and refractive outcomes and rotational stability of toric intraocular lens (IOL) implantation in eyes with previous ocular surgeries.

METHODS

This controlled, longitudinal cohort study included a total of 133 eyes (59 study cases with a history of corneal, vitreoretinal, and/or glaucoma surgery and 74 randomly selected controls without a history of ocular surgery) that had cataract and corneal astigmatism treated with toric IOL implantation. Postoperative outcomes were recorded at postoperative 1 month and 3 to 12 months.

RESULTS

Refractive prediction errors were within ±1.00 diopter (D) of target in 93.5% and 88.4% of the study cases at postoperative 1 month and 3 to 12 months, respectively. They were within ±0.50 D of target in 56.5% and 60.5% of the cases during the same follow-up intervals, respectively. Study cases showed statistically significantly inferior uncorrected distance visual acuity (UDVA) compared to controls at 1 month postoperatively (0.27 ± 0.24 and 0.17 ± 0.21 logMAR, respectively, P = .027) but not during the later follow-up (0.19 ± 0.19 and 0.16 ± 0.19 logMAR, respectively, P = .431). Corrected distance visual acuity (CDVA) was slightly lower in the study cases than in controls at 1 month postoperatively (0.13 ± 0.16 and 0.07 ± 0.14, respectively, P = .005) and subsequent follow-up months (0.10 ± 0.13 and 0.03 ± 0.10, respectively, P < .001). Of the examined study cases, 93.9% and 88.4% had IOL axes within 5° of intended axis at postoperative 1 month and 3 to 12 months, respectively.

CONCLUSIONS

Toric IOLs provided significant and sustained improvement in visual acuity and refraction in eyes with a history of prior ophthalmic surgery. Refractive outcomes achieved postoperatively were comparable to those in eyes without a prior history of ophthalmic surgery, although the rate of visual recovery may be different. [J Refract Surg. 2019;35(12):781-788.].

[Refractive shift after glaucoma surgery]

Filtering glaucoma surgery can affect certain biometric features of the eye: it can change the axial length and anterior chamber depth, while redistribution of mechanical tensions in the fibrous tunic can alter the shape of the cornea. Among these changes that affect refraction, reshaping of corneal curvature is the principle one. Contrary to the expectations, and in contrast to changes associated with cataract surgery, glaucoma surgery led to decrease in vertical corneal radius (steepening) and development of the with-the-rule astigmatism. A number of studies helped reveal the features of corneal astigmatism that appears after glaucoma surgery: its power, duration, possibility of horizontal meridian flattening, influence of topical cytostatic drugs and drainage devices, etc. Potential reasons of astigmatism development were suggested: conjunctival incisions and sutures in the limbal area, quantity and strength of flap sutures, intraocular pressure level, shift of fistula edges, tissue contraction after cauterization, etc. The key role in pathogenesis of the refractive shift due to change of corneal curvature may belong to particularities of wound healing in the cornea and sclera: healing in sclera is similar to one of connective tissue - its ultrastructure undergoes aging process followed by change of rigidity. At the same time, the main reason for the development of corneal astigmatism after glaucoma surgery remains unclear.

Forecasting Single Disease Cost of Cataract Based on Multivariable Regression Analysis and Backpropagation Neural Network

In medical services, charge according to the disease is an important way to promote the reform of pricing mechanism, control the unreasonable growth of medical expenses, as well as reduce the burden on patients. Single disease cost forecasting that both identify potential influencing or driving factors and enable better proactive estimation of costs can guide the management and control of medical costs. This study aimed to identify the factors that affect the medical costs of single disease cataract and compare 2 regression models for anticipating acceptable medical cost forecasts. For this purpose, 483 patients with cataract surgery completed in West China Hospital from May 1, 2015, to October 1, 2015, were selected from hospital information system. For cost forecasting, multivariable regression analysis (MRA) and backpropagation neural network (BPNN) were used. Analysis of data was performed with SPSS21.0 and MATLAB2014a software. Total medical costs of patients with cataract (n = 483) ranged from 2015.00 to 13 359.00 CNY, and the mean ± standard deviation is 6292.29 ± 2639.43 CNY. Factors influencing costs of cataract in the MRA include, in importance order, intraocular lens (IOL) implantation (|r|: 0.805, P < .01), doctor level (|r|: 0.644, P < .01), payment source (|r|: 0.554, P < .01), admission status (|r|: 0.326, P < .01), additional diagnosis (|r|: 0.260, P < .01), type of surgery (|r|: 0.127, P < .05), and type of anesthesia (|r|: 0.126, P < .05). In terms of forecasting performance, BPNN (average error: 2.81%) outperforms, yet is less interpretable than MRA (average error: 5.79%). Both MRA and BPNN are technically and economically feasible in generating medical costs of cataract. And some insights on using results of the forecasting model in controlling and reducing disease costs are obtained.

Correlations of Corneal Spherical Aberration with Astigmatism and Axial Length in Cataract Patients

Purpose

To clarify the distribution of corneal spherical aberrations (SAs) in cataract patients with different corneal astigmatism and axial length.

Setting

Department of Ophthalmology and Vision Science of the Eye and ENT Hospital of Fudan University, Shanghai, China.

Design

Retrospective case series.

Methods

The axial length, corneal SAs, and other corneal biometrics were collected in cataract patients with Pentacam HR and IOLMaster 500. The statistical analysis of the corneal SAs was based on the stratification of axial length and anterior corneal astigmatism.

Results

In total, 6747 eyes of 6747 patients were recruited, with 2416 eyes (58.17 ± 16.81 years old) in the astigmatism group (anterior corneal astigmatism ≥1 D) and others (61.82 ± 12.64 years old) in the control group. In patients with astigmatism <2 D, the total and anterior SAs decreased as the axial length increased (P < 0.001). The total corneal SAs of patients with astigmatism of 2-3 D stabilized at around 0.29 μm, whereas those of patients with anterior corneal astigmatism ≥3 D tended to be variable. Age and anterior corneal astigmatism had positive and negative effects, respectively, on SA in the regression model.

Conclusions

Axial length has a negative effect on the anterior and total corneal SAs, which stabled around 0.33 μm and 0.30 μm in patients with axial length of ≥26 mm, respectively. Individualized SA adjustments are essential for patients undergoing aspheric toric IOL implantation with preoperative anterior corneal astigmatism of 1-2 D or ≥3 D. Toric IOLs with a negative SA of −0.20 μm are recommended for patients with anterior corneal astigmatism of 2-3 D if no customized therapy is warranted.