Rongrong Gao

Efficacy Comparison of 16 Interventions for Myopia Control in Children: A Network Meta-analysis

PURPOSE To determine the effectiveness of different interventions to slow down the progression of myopia in children. METHODS We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov from inception to August 2014. We selected randomized controlled trials (RCTs) involving interventions for controlling the progression of myopia in children with a treatment duration of at least 1 year for analysis. MAIN OUTCOME MEASURES The primary outcomes were mean annual change in refraction (diopters/year) and mean annual change in axial length (millimeters/year). RESULTS Thirty RCTs (involving 5422 eyes) were identified. Network meta-analysis showed that in comparison with placebo or single vision spectacle lenses, high-dose atropine (refraction change: 0.68 [0.52-0.84]; axial length change: -0.21 [-0.28 to -0.16]), moderate-dose atropine (refraction change: 0.53 [0.28-0.77]; axial length change: -0.21 [-0.32 to -0.12]), and low-dose atropine (refraction change: 0.53 [0.21-0.85]; axial length change: -0.15 [-0.25 to -0.05]) markedly slowed myopia progression. Pirenzepine (refraction change: 0.29 [0.05-0.52]; axial length change: -0.09 [-0.17 to -0.01]), orthokeratology (axial length change: -0.15 [-0.22 to -0.08]), and peripheral defocus modifying contact lenses (axial length change: -0.11 [-0.20 to -0.03]) showed moderate effects. Progressive addition spectacle lenses (refraction change: 0.14 [0.02-0.26]; axial length change: -0.04 [-0.09 to -0.01]) showed slight effects. CONCLUSIONS This network analysis indicates that a range of interventions can significantly reduce myopia progression when compared with single vision spectacle lenses or placebo. In terms of refraction, atropine, pirenzepine, and progressive addition spectacle lenses were effective. In terms of axial length, atropine, orthokeratology, peripheral defocus modifying contact lenses, pirenzepine, and progressive addition spectacle lenses were effective. The most effective interventions were pharmacologic, that is, muscarinic antagonists such as atropine and pirenzepine. Certain specially designed contact lenses, including orthokeratology and peripheral defocus modifying contact lenses, had moderate effects, whereas specially designed spectacle lenses showed minimal effect.

Cross-cultural validation of the National Eye Institute Visual Function Questionnaire

Purpose To assess the native and the previously Rasch‐modified National Eye Institute Visual Function Questionnaire (NEI VFQ) scales in a Chinese population. Setting Eye Hospital of Wenzhou Medical University, Wenzhou, China. Design Questionnaire development. Methods Patients on the waiting list for cataract surgery completed the 39‐item NEI VFQ (NEI VFQ‐39). Rasch analysis was performed in 3 steps as follows: (1) Assess the psychometric properties of the original NEI VFQ. (2) Reassess the previously proposed Rasch‐modified NEI VFQ scales by Pesudovs et al. (2010) in Chinese populations. (3) Compare the scores of previously recommended scales of the NEI VFQ with new Rasch‐modified scales of the same questionnaire using Bland‐Altman plots. Results Four hundred thirty‐five patients (median age 70 years; range 35 to 90 years) completed the NEI VFQ‐39. Response categories for 4 question types were dysfunctional and therefore repaired. The original NEI VFQ‐39 and NEI VFQ‐25 showed good measurement precision. However, both versions showed multidimensionality, misfitting items, suboptimum targeting, and nonfunctioning subscales. Using the previously proposed Rasch‐modified scales of the NEI VFQ yielded valid measurement of each construct in the 39‐item and 25‐item questionnaire. Comparison between the earlier proposed NEI VFQ scales and the new versions developed in this population showed good agreement. Conclusions The original NEI VFQ was once again found to be flawed. The previously proposed Rasch‐analyzed versions of the NEI VFQ and the new Chinese versions showed good agreement. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Translation, cultural adaptation, and Rasch analysis of the visual function (VF-14) questionnaire

PURPOSE To translate, culturally adapt, and validate the original and previously validated shorter versions of the Visual Function Index (VF-14) questionnaire in a Chinese population. METHODS The VF-14 was completed by patients with cataract. The analysis was carried out in three phases: phase I, testing whether the VF-14 and its valid shorter versions,VF-8R and VF-11R, form valid scales in Chinese settings using Rasch analysis; phase II, developing completely new Chinese versions of the VF-14; phase III, testing whether the previously validated shorter versions of the VF-14 could be applied in a Chinese population. This was tested by assessing the agreement between the new Chinese (developed in phase II) and the previously validated shorter versions of the VF-14 using Bland-Altman plots. RESULTS A total of 456 patients (median age, 70 years; range, 40-92 years; females, 58%) completed the Chinese translated version of the VF-14. The VF-14 and the VF-11R demonstrated good Rasch based psychometric properties when a grossly misfitting item was removed. The VF-8R formed a valid scale without any modification. The scores of the VF-11R and the Chinese shorter version (VF-11RChin) showed very good agreement, with a mean difference of -0.18 logits and 95% limits of agreement between 0.11 and -0.47. CONCLUSIONS The Chinese translated VF-14, VF-11R, and VF-8R were valid and could be applied to assess cataract outcomes in Chinese settings. The existing shorter version had good agreement with the new Chinese version, which signifies that there was no need to develop a different version of the VF-14 in China.

Comparison of ocular biometric measurements between a new swept-source optical coherence tomography and a common optical low coherence reflectometry

The purpose of the current study was to compare the measurements between a new optical biometer based on swept-source optical coherence tomography (SS-OCT), the OA-2000 (Tomey, Japan), and an optical biometer based on optical low coherence reflectometry (OLCR), the Lenstar (Haag-Streit, Switzerland). Ninety-nine eyes of 99 healthy subjects were included. The axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth (AD), lens thickness (LT), keratometry (K) readings, including flat K (Kf), steep K (Ks), mean K (Km), astigmatism vectors J0, J45 at diameters of 2.5 and 3.0 mm, and white-to-white diameter (WTW) were measured three times each using both biometer in normal eyes by random sequence. Bland-Altman analysis showed good agreement between the SS-OCT and OLCR devices for AL, AD, ACD, LT, with narrow 95% LoA (−0.05 to 0.07 mm, −0.09 to 0.10 mm, −0.10 to 0.09 mm, and −0.06 to 0.22 mm, respectively), and the P values of ACD were both >0.05. The CCT, Kf, Ks, Km, J0, J45 and WTW values provided by the OA-2000 were in good agreement with the Lenstar, and statistically significant differences were detected for some of them but not clinical differences. The agreement was excellent especially for AL.

Precision of Corneal Thickness Measurements Obtained Using the Scheimpflug-Placido Imaging and Agreement with Ultrasound Pachymetry

Purpose. To assess the reliability and comparability of measuring central corneal thickness (CCT) and thinnest corneal thickness (TCT) using a new Scheimpflug-Placido analyzer (TMS-5, Japan) and ultrasound (US) pachymetry. Methods. Seventy-six healthy subjects were prospectively measured 3 times by 1 operator using the TMS-5, 3 additional consecutive scans were performed by a second operator, and ultrasound (US) pachymetry measurements were taken. The test-retest repeatability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were calculated to evaluate intraoperator repeatability and interoperator reproducibility. Agreement among the devices was assessed using Bland-Altman plots and 95% limits of agreement (LoA). Results. The intraoperators TRT and CoV were <19 μm and 2.0%, respectively. The interoperators TRT and CoV were <12 μm and 1.0%, respectively, and ICC was >0.90. The mean CCT and TCT measurements using the TMS-5 were 15.97 μm (95% LoA from −26.42 to −5.52 μm) and 20.32 μm (95% LoA from −30.67 to −9.97 μm) smaller, respectively, than those using US pachymetry. Conclusions. The TMS-5 shows good repeatability and reproducibility for measuring CCT and TCT in normal subjects but only moderate agreement with US pachymetry results. Caution is warranted before using these techniques interchangeably.

Rasch analysis of three dry eye questionnaires and correlates with objective clinical tests

PURPOSE To assess the psychometric properties of Chinese versions of the Ocular Comfort Index (OCI), Ocular Surface Disease Index (OSDI) and McMonnies questionnaires. Further, to assess the correlation between questionnaire scores and objective dry eye disease (DED) clinical tests. METHODS Translated versions of the OCI, OSDI and McMonnies questionnaires were completed in a random order by 238 participants with DED. Objective clinical tests included visual acuity (VA), fluorescein tear film break-up time (TBUT), corneal fluorescein staining, Schirmer I testing and meibomian gland grading. Rasch analysis was used to assess questionnaire psychometrics and spearman rank for correlations. RESULTS For the OCI, the person separation was 2.31, item infit and outfit statistics ranged from 0.74-1.14 and 0.75-1.32, respectively, and targeting 1.54 logits. For the OSDI, person separation was 0.94. None of the three subscales provided valid measurements based on Rasch analysis. For the McMonnies questionnaire, person separation was 1.17, item infit and outfit statistics ranged from 0.7 to 1.21 and 0.51-3.49, respectively. There were weak correlations between questionnaire scores and clinical tests. There were weak correlations between OSDI scores and VA, fluorescein TBUT, Schirmer I testing and corneal fluorescein staining. There were weak correlations between McMonnies scores and VA, fluorescein TBUT, Schirmer I testing, and corneal fluorescein staining and meibomian gland grading. CONCLUSIONS The OCI questionnaire was the only questionnaire that provided valid measurement on the basis of Rasch analysis, although slight multidimensionality was found. There were weak correlations between OCI scores and fluorescein TBUT, Schirmer I testing, and corneal fluorescein staining. Due to this paradoxical disconnect between symptoms and signs and the repeatability of tests, the use of both subjective and objective markers in the clinical management of patients or as endpoints in clinical trials would appear prudent.

Assessment of Cataract Surgery Outcome Using the Modified Catquest Short-Form Instrument in China.

Purpose To assess cataract surgery outcome using the Rasch scaled Chinese version of the Catquest short-form. Methods The Chinese translated and culturally adapted version of the Catquest-9SF was interviewer-administered to patients, pre and post cataract surgery. Rasch analysis was performed on the baseline data to revise the Catquest. For the surgical outcome assessment, we stacked pre- and post-surgical Catquest data to demonstrate improvement in visual function scores and responsiveness of the instrument to cataract surgery. Results A total of 247 cataract patients (median age, 70 yrs; male 51.0%) completed the Catquest 9SF at baseline.The Catquest-9SF possessed adequate measurement precision of 2.15. No disordering of response categories were observed and all the items perfectly fit to the Rasch model except item 7 (outfit >1.5). A slight reduction in precision was observed after removing misfitting item 7 (Catquest-8SF-CN), but the precision value was well above the acceptable value of 2.00. Notably, the instrument was well targeted (mean person location 0.30), demonstrated no evidence of multidimensionality and DIF. At 12 months post-surgery, 74 (30%) patients came for follow-up and completed the Catquest. There was a significant improvement in the Catquest scores post cataract surgery with a considerably large effect size. Conclusion The Catquest-8SF-CN demonstrated promising Rasch based psychometric properties and was highly responsive to cataract surgery.

Corneal elevation in a large number of myopic Chinese patients

PURPOSE To establish a normative database for corneal elevation in Chinese myopic patients who underwent refractive surgery, and analyze the association of corneal elevation with sex, age, and ocular parameters. METHODS A total of 3000 eyes in 1500 patients were evaluated with the Pentacam. Anterior and posterior elevations were measured at the apex and thinnest point. Normative thresholds were defined according to the Tukey method. Univariate and multivariate analyses were performed to assess the association of corneal elevation with sex, age, and ocular parameters. RESULTS Normal upper limits for corneal elevation in adult Chinese were 4.95μm, 5.25μm, 6.2μm, and 11.0μm at the anterior apex, anterior thinnest point, posterior apex, and posterior thinnest point, respectively. Thinner corneal pachymetry at the apex and greater anterior corneal astigmatism tended to show greater anterior corneal elevation values. Younger age, greater anterior corneal astigmatism, lower anterior and posterior keratometry, and shallower anterior chamber depth resulted in greater posterior corneal elevation values. CONCLUSIONS Locally derived thresholds may offer higher sensitivity and specificity when screening eyes for myopic refractive surgery, and keratoconic and post-orthokeratology eyes. Anterior and posterior corneal elevation at the apex and thinnest point were associated significantly with anterior corneal astigmatism, showing a positive correlation.

Repeatability, Reproducibility, and Agreement of Two Scheimpflug-Placido Anterior Corneal Analyzers for Posterior Corneal Surface Measurement.

PURPOSE To evaluate the intraoperator repeatability and interoperator reproducibility of two Scheimpflug-Placido anterior corneal analyzers (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy, and TMS-5; Tomey, Nagoya, Japan) for the measurement of posterior corneal surface in normal eyes and the agreement between the two devices. METHODS The current prospective study investigated 55 right eyes of 55 healthy patients in a random order. The posterior steep keratometry (Ks), flat keratometry (Kf), mean keratometry (Km), and astigmatism were randomly measured by two independent experienced operators using the Sirius and TMS-5 Scheimpflug-Placido systems. Three consecutive measurements were obtained. Vector analysis was used for astigmatism. To assess intraoperator repeatability and interoperator reproducibility, within-subject standard deviation (Sw) and test-retest repeatability (TRT, 2.77 Sw) were calculated. The Bland-Altman plots and 95% limits of agreement (LoA) were used to evaluate the agreement between the two systems. RESULTS In the Sirius Scheimpflug-Placido system, the Sw and TRT of keratometry and astigmatism were less than 0.04 and 0.12 diopters (D), respectively. The interoperator Sw and TRT were less than 0.03 and 0.07 D, respectively. In the TMS-5 Scheimpflug-Placido system, the intraoperator Sw and TRT did not exceed 0.03 and 0.08 D, respectively. The interoperator Sw and TRT were no greater than 0.02 and 0.05 D, respectively. All parameters showed minor fluctuations in the 95% LoA. CONCLUSIONS Both Scheimpflug-Placido systems show high repeatability and reproducibility for posterior corneal surface measurement. A high concordance between the two devices suggests interchangeable use in normal eyes. [J Refract Surg. 2017;33(8):524-530.].

Validation of an instrument to assess visual ability in children with visual impairment in China

Objective To validate a visual ability instrument for school-aged children with visual impairment in China by translating, culturally adopting and Rasch scaling the Cardiff Visual Ability Questionnaire for Children (CVAQC). Methods The 25-item CVAQC was translated into Mandarin using a standard protocol. The translated version (CVAQC-CN) was subjected to cognitive testing to ensure a proper cultural adaptation of its content. Then, the CVAQC-CN was interviewer-administered to 114 school-aged children and young people with visual impairment. Rasch analysis was carried out to assess its psychometric properties. The correlation between the CVAQC-CN visual ability scores and clinical measure of vision (visual acuity; VA and contrast sensitivity, CS) were assessed using Spearmans r. Results Based on cultural adaptation exercise, cognitive testing, missing data and Rasch metrics-based iterative item removal, three items were removed from the original 25. The 22-item CVAQC-CN demonstrated excellent measurement precision (person separation index, 3.08), content validity (item separation, 10.09) and item reliability (0.99). Moreover, the CVAQC-CN was unidimensional and had no item bias. The person–item map indicated good targeting of item difficulty to person ability. The CVAQC-CN had moderate correlations between CS (−0.53, p<0.00001) and VA (0.726, p<0.00001), respectively, indicating its validity. Conclusions The 22-item CVAQC-CN is a psychometrically robust and valid instrument to measure visual ability in children with visual impairment in China. The instrument can be used as a clinical and research outcome measure to assess the change in visual ability after low vision rehabilitation intervention.