Analysis of related factors of optical quality in healthy Chinese adults: a community-based population study.

BACKGROUND: In recent years, visual quality has been extensively investigated in various conditions. In this community-based population study, we analyzed the effects of aging, refraction, and Lens Opacification Classification System III (LOCSIII) score on retinal imaging quality in healthy Chinese adults. METHODS: This cross-sectional study was conducted on sub-group subjects from The Handan Eye Study between October 2012 and January 2013. Healthy subjects over 30-years-old with logarithm of the minimal angle of resolution (logMAR) best-corrected visual acuity (BCVA) less than 0 were included. Retinal image quality was measured by optical quality analysis system (OQAS) and recorded as modulation transfer function cutoff frequency (MTFcutoff), OQAS value (OV) 100%, OV20%, OV9%, Strehl ratio (SR), and objective scatter index (OSI). The correlation between age, spherical equivalent refraction (SE), LOCSIII score, and optical quality parameters were investigated by multivariate analysis. RESULTS: Among 1108 verified subjects, 690 subjects (1380 eyes) met the inclusion criteria. Their age ranged from 30 to 76 years, SE ranged from -4.75 to 2.75 D. They were divided into five age groups (30-39, 40-49, 50-59, 60-69, and ≥70 years) for further analysis. After multivariate analysis by mixed-effect linear model, SR (t =  -3.03, P = 0.002), OV20% (t = -2.39, P = 0.017), and OV9% (t = -3.16, P = 0.001) significantly decreased with the increasing age, whereas logMAR BCVA (t = 4.42, P < 0.001) and OSI (t = 4.46, P < 0.001) significantly increased with age. As SE increased, SR (t = 2.74, P = 0.01), OV20% (t = 2.31, P = 0.02), and OV9% (t = 2.79, P = 0.005) significantly elevated, and OSI (t = -3.38, P < 0.001) significantly decreased. With the increase in cortical opacity score, all optical quality parameters except for SR significantly decreased, including MTFcutoff (t = -2.78, P = 0.01), OV100% (t = -2.78, P = 0.005), OV20% (t = -2.60, P = 0.009), and OV9% (t = -2.05, P = 0.040). As posterior sub capsular opacity score increased, MTFcutoff (t = -2.40, P = 0.02) and OV100% (t = -2.40, P = 0.01) significantly decreased, while OSI (t = 7.56, P < 0.001) significantly increased. CONCLUSIONS: In healthy Chinese adult population, optical quality-related parameters significantly decrease with the increasing age, and OSI significantly increases with age. In normal BCVA subjects, optical quality is significantly impacted by cortical and posterior sub capsular opacity rather than by nuclear opacity.

Reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.

AIM: To evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system. METHODS: Thirty Chinese healthy adults (19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System (OQAS) with an artificial pupil diameter of 4.0 mm. RESULTS: With each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency (MTFcutoff), the Strehl(2D) ratio, the OQAS values (OVs) at contrasts of 100%, 20%, 9% and the objective scatter index (OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit (RL) and the coefficient of repeatability (COR). Reproducibility of the two methods was evaluated by intra-class correlation coefficient (ICC) and the 95% limits of agreement (Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs (percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13% and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83% and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters (in comparison of the two methods) ranged from -0.57 to 42.18 (MTFcutoff), -0.01 to 0.23 (Strehl(2D) ratio), -0.02 to 1.40 (OV100%), -0.10 to 1.75 (OV20%), -0.14 to 1.80 (OV9%) and -1.46 to 0.18 (OSI). CONCLUSION: Measurements provided by OQAS with either method showed a good repeatability. However, the results obtained from the two different measurement methods showed a poor reproducibility. These findings suggest that it might be best to evaluate patients' optical quality by OQAS using the best focus as chosen automatically by the instrument.

Effect of refractive correction on ocular optical quality measurement using double-pass system.

BACKGROUND: Optical Quality Analysis System II (OQAS, Visiometrics, Terrassa, Spain) that uses double-pass (DP) technique is the only commercially available device that allows objective measurement of ocular retinal image quality. This study aimed to evaluate the impact of spectacle lenses on the ocular optical quality parameters and the validity of the optometer within OQAS. METHODS: Seventy eyes of healthy volunteers were enrolled. Optical quality measurements were performed using OQAS with an artificial pupil diameter of 4.0 mm. Three consecutive measurements were obtained from spectacle correction corresponding to subjective refraction and from the OQAS built-in optometer separately. The modulation transfer function cutoff frequency, the Strehl ratio, the width of the point spread function (PSF) at 10% of its maximal height (PSF10), and the width of the PSF at 50% of its maximal height (PSF50) were analyzed. RESULTS: There was no significant difference in any of the parameters between the spectacle correction and the optometer correction (all P > 0.05, paired t-test). A good agreement was found between both the methods and a good intraobserver repeatability in both the correction methods. Difference in best focus between two methods was the only parameter associated significantly with optical quality parameter differences. Best focus difference, built-in optometer correction with or without external cylindrical lens, and age were associated significantly with PSF10 difference. No linear correlation between refractive status and optical quality measurement difference was observed. A hyperopic bias (best focus difference of (0.50 ± 0.44) D) and a relatively better optical quality using spectacle correction in high myopia group were found. CONCLUSIONS: OQAS based on DP system is a clinically reliable instrument. In patients with high myopia, measurements using built-in optometer correction should be considered and interpreted with caution.

[Comparison between binocular, open-field auto ref/keratometer and conventional autorefractor].

OBJECTIVE: To compare the refractive results between open-field auto ref/keratometer and conventional autorefractor, and to investigate the effect of cycloplegic to this difference. METHODS: Three hundred and four primary and secondary school students were consecutively enrolled in Beijing Tongren Hospital. Non-cycloplegic and cycloplegic objective refractions were performed for each subject by conventional autorefractor (Accuref-K9001, Shin Nippon, Japan) and binocular, open-field auto ref/keratometer (Grand Seiko Co., Ltd., Hiroshima, Japan). The coincidence rate of sphere, spherical equivalent (SE) and axis (defined as difference of diopter ≤ 0.50 D, difference of axis degree ≤ 20°) were calculated; Bland-Altman and distribution analysis were performed according to mean and difference of SE. RESULTS: The coincidence rate of sphere, SE and axis were 77.3%, 78.6% and 66.0% before cycloplegic and increased to 94.4%, 95.1% and 69.5% after cycloplegic, respectively. The difference (95%CI) of SE before cycloplegic between these two refractometers was 0.12 (-1.04 to 1.29) D and was positively correlated with the mean of SE (after cycloplegic) (r(pearson) = 0.21, P < 0.001). The difference (95%CI) of SE after cycloplegic was -0.08 (-0.60 to 0.45) D. The difference (95%CI) of SE of K9001 autorefractor before and after cycloplegic was larger than that of WAM autorefractor [0.51 (-0.83 - 1.84) D and 0.31 (-0.66 to 1.28) D, P < 0.001]. Before cycloplegic, SE measured by WAM autorefractor showed myopic more than 0.25 D than K9001 (group 1) was found in 51 (16.8%) subjects; difference within 0.25 D was found in 160 (52.6%) subjects; hyperopic more than 0.25 D (group 3) was found in 93 (30.6%) subjects. After cycloplegic, 69 (22.7%) subjects were found in group 1, and subjects increased to 213 (70.1%) and decreased to 22 (7.2%) in group 2 and group 3, respectively. CONCLUSION: The binocular, open-field auto ref/keratometer provides more hyperopic readings than conventional autorefractor. It will be useful in both clinical screening and scientific research because it produces less instrument myopia than that of conventional autorefractor.

Estrogen receptor expression in adrenocortical carcinoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>Adrenocortical carcinoma (ACC) is a rare but highly malignant tumor, and its diagnosis is mostly delayed and prognosis is poor. We report estrogen receptor (ER) expression in this tumor and our clinical experiences with 17 ACC cases.</p><p><b>METHODS</b>The data of the 17 patients (9 females and 8 males, age range from 16 to 69 years, mean age of 42.6 years) with ACC were reviewed, and symptoms, diagnostic procedures, treatment, and results of follow-up were evaluated. Immunohistochemistry was used to detect ER expression in tumor samples from the 17 patients.</p><p><b>RESULTS</b>At the time of diagnosis, 4 tumors were classified as Stage I, 4 as Stage II, 3 as Stage III, and 6 as Stage IV. Eight patients demonstrated positive nuclear immunostaining of ER. The prognosis of patients with ER positive was significantly better (P<0.05) than that of patients with ER negative, with 1- and 5-year survival rates at 86% and 60% for ER-positive patients, and 38% and 0% for ER-negative patients, respectively.</p><p><b>CONCLUSION</b>ER-positivity may be one of the factors associated with a worse prognosis of ACC.</p>