Objective: To investigate the status of myopia in primary and middle school students in Gansu province. Methods: By using a stratified cluster random sampling method, 11 480 primary and middle school students from Lanzhou, Tianshui, Qingyang, Wuwei, Gannan Tibetan autonomous prefecture and Hui autonomous prefecture of Linxia in Gansu province from Decembere 2014 to September 2015, were enrolled in this study. A health questionnaire was used to investigate the students’ habits for eye use and their ophthalmic status was investigated by measuring general visual acuity, computer optometry, and refractive parameters (measured by optical coherence biometry, IOLMaster). Chi-square and logistic regression analysis was performed on the myopia-related factors. Results: The results showed that the total prevalence of myopia was 71.33% in primary and middle school students in Gansu province. The prevalence of myopia was 70.49% and 72.23% in males and females, respectively. The prevalence of myopia was 74.46% and 66.56%, respectively, in urban and rural students. The higher the grade level, the more serious the degree of myopia. Logistic regression analysis showed that after the passage of individual behavior, close work, outdoor activities and time are the main factors for myopia. Conclusion: Primary and middle school students in Gansu province have a high prevalence of myopia. Promoting students’ healthy habits and improving students’ awareness for protecting eyesight should be applied.

Objective: To investigate differences in accommodative parameters between progressive myopic and emmetropic children, and to determine the potential role of accommodation in myopia. Methods: Thirty?four children with progressive myopia (SE of -0.75 D or more) and 34 children with emmetropia (SE between -0.50 D and 0.50 D) from December 2015 to May 2016 in Eye Hospital, Wenzhou Medical ·论著·Original Article· 引用本文：陈云云, 丁程璐, 张川川, 等. 进展性近视与正视儿童眼调节功能特征比较. 中华眼视光学与视觉科学杂志, 2019, 21(5): 334-338. DOI: 10.3760/cma.j.issn.1674- 845X.2019.05.003. 中华眼视光学与视觉科学杂志，2019，21（5） Chin J Optom Ophthalmol Vis Sci, 2019, 21(5) ·335· University participated in this case control study. Subjective accommodative amplitude (SAA), monocular distance accommodative facility (DAF) and accommodative stimulus-response curves (ASRCs) were measured. An independent samples t test was used to compare differences in accommodation between those two groups. Results: Mean SE was 0.18±0.28 D and -2.88±1.03 D for emmetropes and progressive myopes, respectively (t=-16.72, P<0.001). The SAA of progressive myopes was significantly lower than that for emmetropes (t=-2.22, P=0.03). No differences were found in the DAF, OAA, and ASRC slopes between the two groups (all P>0.05). Progressive myopic children had a larger accommodative lag area and higher accommodative lag at 1 D, 2 D, 3 D, 4 D, 5 D than emmetropes (t=2.40, 2.78, 2.79, 2.49, 2.12, all P<0.05). Accommodative lag at 6 D was slightly higher in progressive myopes, but no significant difference was found (t=1.83, P=0.07). Conclusions: The features of accommodative function in progressive myopic children are not exactly the same as emmetropes. Progressive myopic children have a higher accommodative lag than emmetropes, suggesting that accommodative lag may play a role in myopia.

Objective: To investigate stimulus and response accommodative convergence to accommodation (AC/A) and stimulus and response convergence accommodation to convergence (CA/C ) ratios between different refractive groups and heterophoria groups. The correlations between the four parameters were also investigated. Methods: In this case control study, 20 emmetropes (EMM) and 27 early-onset myopes (EOM) aged 9 to 14 years participated in this descriptive study from October 2016 to January 2017 at Eye Hospital, Wenzhou Medical University. The accommodative response and phoria through five accommodative stimuli and 6 convergence stimuli levels were measured at 25 cm under binocular viewing conditions with a Grand Seiko WAM-5500 autorefractor and a modified Thorington card. Data were analyzed using t-tests and Pearson correlation analysis. Results: Response AC/A ratios of the EMM and the EOM groups were 4.07±1.47 Δ /D and 5.13±1.95 Δ /D, respectively; the difference between the two groups was significant (t=2.12, P=0.04). A significant linear correlation was found between the stimulus and response AC/A ratios in both the EMM and EOM groups (r=0.903, P<0.001; r=0.880, P<0.001). A negative correlation was found between the response AC/A and CA/C ratios in the EMM group (r=-0.450, P=0.04), while no correlation was found between these two ratios in the EOM group (r=-0.367, P=0.06). Conclusions: EOM has a higher response AC/A ratio compared to EMM. The negative correlation between AC/A and CA/C was only found between the response ratios of EMM, indicating that the AC/A ratio cannot provide a true representation of both cross-link interactions.

Objective: To detect the pathogenetic mechanism of motion-sensitive cortical deficit in response to motion stimuli in children with anisometropic amblyopia using a blood oxygenation level-dependent functional magnetic resonance imaging technique (BOLD-fMRI). Methods: This was a case series study. Patients were collected from June to December 2017 at Tianjin Eye Hospital. Twenty-five patients who were diagnosed with anisometropic amblyopia as amblyopia group and twenty-five normal volunteers were examined as control group. A BOLD-fMRI technique on a 1.5T MRI and a horizontally moving sinusoidal grating block design were used for task conditions. All data were processed with SPM5 software, were analyzed by t test. Results: Significant fMRI activation and comparable right and left eye activation were found in the middle temporal area (MT), and Brodmann areas 19 and 37, in all control subjects; Lesser cortical activation in area MT and Brodmann areas 37, 19, and greater activation in the frontal gyrus of the lazy eye group were detected compared to the control group. Lesser cortical activation in Brodmann area 37, 18 of the contralateral eye of the amblyopic group was detected compared to the control group. Lesser cortical activation in area MT and Brodmann areas 19, 18, and greater activation in the frontal lobes of the anisometropic amblyopic eyes were detected compared to the contralateral eyes. Conclusions: The spatial extent and intensity of the visual cortex activation in the visual cortex decreases in the amblyopic eye compared to the normal control. Decreased cortical activation in the fellow eye is prevalent. A greater visual cortex area is activated when stimulating the amblyopic eye.

Objective: To determine the effects of moderately intense aerobic exercise on intraocular pressure in young healthy adults. Methods: Twenty-eight volunteers performed moderately intense aerobic exercise for 30 minutes on a treadmill in this prospective study. Measurements of intraocular pressure (IOP), blood pressure and ocular perfusion pressure (OPP) were taken before and after exercise for 10, 20 and 30 minutes and after rest for 10 and 30 minutes. IOP was measured by iCare tonometry. Blood pressure was measured by an electronic sphygmomanometer. OPP was calculated using the formula, OPP=2/3 MAP (mean arterial pressure)-IOP. A repeated measures analysis was used to compare IOP, SBP, DBP and OPP. Results: Finally, 27 cases 27 eyes were included. ①There was a statistically significant difference (F=75.0, P<0.001) in IOP at baseline, and after moderately intense aerobic exercise for 10, 20 and 30 minutes andafter rest for 10 and 30 minutes. IOP at 10, 20 and 30 minutes of exercise was significantly lower than that at baseline (all P<0.001). ②There were statistically significant differences (F=31.7, P<0.001; F=19.7, P<0.001) in the SBP and DBP at baseline, and after moderately intense aerobic exercise for 10, 20 and 30 minutes and after rest for 10 and 30 minutes. SBP and DBP at 10, 20 and 30 minutes of exercise were significantly higher than that at baseline (all P<0.001). ③There was a statistically significant difference (F=56.9, P<0.001) in the OPP at baseline, and after moderately intense aerobic exercise for 10, 20 and 30 minutes and after rest for 10 and 30 minutes. OPP at 10, 20 and 30 minutes of exercise was significantly higher than that at baseline (all P<0.001). ④There were no statistically significant differences in IOP, SBP, DBP or OPP at baseline and after rest for 10 and 30 minutes. Conclusion: There is a significant decrease in IOP and significant increase in SBP, DBP and OPP following moderately intense aerobic exercise. After 10 minutes of rest, IOP, SBP, DBP and OPP return to baseline.

Objective: To analyze the application of a medical imaging artificial intelligence system for spontaneous fluorescence imaging recognition using pre-clinical diabetic retinopathy as an example so as to provide a technical exploration for early diagnosis and treatment. Methods: The fundus autofluorescence images of 102 patients (200 eyes) in a control group and 105 patients (200 eyes) in a study group were collected from August 2017 to May 2018. All patients were examined by a slit lamp microscope, preview lens, naked eye or corrected visual acuity and fundus autofluorescence images. The images from the control and study groups were used for analysis. The medical image extraction and recognition system is based on a two-dimensional lattice complexity measurement and was used to analyze the discernible differences between the fundus autofluorescence image of pre-clinical diabetic retinopathy and the normal retinal autofluorescence image. Results: Twenty-five features with comparative significance were extracted. The single and multiple features were tested by 10-fold and 5-fold cross tests for 25 features, and the accuracy rate was 82.47%. Conclusions: Complex analysis of a medical imaging artificial intelligence system can be used to identify the spontaneous fluorescence changes on the fundus of pre-clinical diabetic retinopathy with high accuracy.

Objective: To identify the relationship between the early changes in central macular thickness (CMT) 24 hours after initial anti-vascular endothelial growth factor (VEGF) injection and the long-term therapeutic effect; to determine the threshold of the long-term prognosis by measuring the receiver operating characteristic (ROC) curve in patients with macular edema (ME) secondary to branch retinal vein occlusion (BRVO). Method: This was a retrospective series of consecutive cases conducted to recruit 276 BRVO patients from December 2014 to December 2016 in the ophthalmic outpatient department of the Second Affiliated Hospital of Harbin Medical University. CMT was measured by OCT before injection, 24 hours after injection, and every 4 weeks up to 48 weeks. The best corrected visual acuity (BCVA) was measured by the ETDRS visual acuity scale. The threshold of the treatment effect at 48 weeks was determined by an ROC curve. Pearson correlation analysis and logistic regression analysis were used to identify the factors that might affect the treatment outcome. Results: All 60 eligible BRVO patients (60 eyes) showed a significant decrease in CMT at each time point after injection and BCVA increased significantly. The decrease in CMT at 24 hours after the first injection was significantly correlated with both the decrease in CMT at 48 weeks (r=0.664, P<0.001), and the change in visual acuity at 48 weeks (r=0.642, P<0.001). ROC curve analysis showed that the 18% decrease in CMT at 24 hours was the most sensitive and specific. According to this threshold, the patients were divided into two groups: 24 cases in group A decreased less than 18% at 24 hours and 36 cases in group B decreased more than 18%. The logistic regression analysis group (<18%) was a positive predictor of cure (OR: 19.549, 95%CI: 4.324-88.378, P<0.01). The improvement in visual acuity was 13±11 and 19±14 letters, respectively, and the difference was statistically significant (t=-1.375, P<0.001). Conclusion: The long-term therapeutic effect of ME secondary to BRVO in patients is correlated with the decline in CMT 24 hours after the first anti-VEGF injection using OCT, the decrease more than 18% predicts a good the long-term therapeutic effect.

Objective: To compare the consistency of OA-2000 with IOLMaster 500 and A-scan for biologicalmeasurements. The purpose of this study was to evaluate the measurements of OA-2000 in preoperative examinations of cataract patients. Methods: In this case series study, a total of 152 patients (152 eyes) diagnosed with age-related cataract were selected at the Affiliated Hospital of Nei Mongol Medical University from May to June 2018. All the patients were examined in turn by OA-2000, IOLMaster 500 and A-scan. Measurements by these three instruments were compared for axial length (AL), Ks/Kf, anterior chamber depth (ACD), white-to-white (W-W), lens thickness (LT) and intraocular lens (IOL) dioptor. The results were analyzed by one-way analysis of variance, Pearson correlation and Bland-Altman. Results: ①The detection rates of AL and ACD with OA-2000, IOLMaster 500, and A-scan were 97.3%, 78.2%, 100%, and 99.3%, 97.3%, 100%, respectively. The detection rates of Ks/Kf with OA-2000 and IOLMaster 500 were 99.3% and 98.6%. The detection rates of W-W with OA-2000 and IOLMaster 500 were 97.3% and 94.7%. Among them, 17 eyes had high myopia, posterior scleral grape swelling and an axial length≥26 mm. The detection rates of AL with OA-2000, IOLMaster 500 and A-scan were 88% (15/17), 65% (11/17), and 100% (17/17). ②There was a significant difference in AL and ACD between the three instruments (F=12.63, P=0.02; F=10.57, P=0.01). The AL, ACD parameters measured by OA-2000 and IOLMaster 500 were not significantly different. There were significant differences in AL and ACD between A-scan and the other two instruments (P<0.001). There were no significant differences in Ks/Kf, IOL or W-W parameters among the three instruments. ③The average difference in AL measurements between OA-2000 and IOLmaster 500 was 0.03 mm, between OA-2000 and A-scan was 0.13 mm. The average difference between the three instruments for AL measurements with an axial length≥26 mm: OA-2000 and IOLmaster 500 was 0.06 mm; OA-2000 and A-scan was 0.43 mm. ④A Pearson correlation analysis showed that there was a high correlation between the measured results of OA-2000 and IOLMaster 500 (r=0.78, P=0.02). ⑤The consistency of AL results using Bland-Altamn analysis showed that there was good consistency in the range of 95% consistency. Conclusion: There was a high consistency in ocular biological measurements between the three instruments in cataract eyes. However, the detection rate of OA-2000 in AL was significantly higher than that of IOLMaster 500, and the accuracy of the OA-2000 measurement was obviously higher in the AL measurement in high myopia with posterior staphyloma.

  Objective: To analyze the causes and identify trends of penetrating keratoplasty (PKP) over the past 10 years. Methods: This was a retrospective case series study. Medical records of patients who underwent  PKP at Qingdao Eye Hospital from January 2013 to December 2017 were collected, and the data was compared to that from the 2005 to 2010 period at the same hospital. Data of patients, including age, sex, and preoperative primary diagnosis for PKP were reviewed. The proportion of the different causes for PKP during 2005-2010 and 2013-2017 was statistically analyzed with a Chi-square test. Results: PKPs were performed on 855 cases from 2013 to 2017. The top four causes were suppurative keratitis (303 cases, 35.4%), regraft (132 cases, 15.4%), keratoconus (130 cases, 15.2%), and herpes keratitis (115 cases, 13.5%). PKPs were performed on 875 cases from 2005 to 2010. The top four causes for PKP were suppurative keratitis, herpes keratitis, keratoconus, and bullous keratopathy. Suppurative keratitis was the first causes for PKP during both periods in 2005-2010 and 2013-2017, and the proportion of the causes for PKP was not significantly different (χ2 =0.543, P=0.461). Regraft increased as the second causes for PKP during 2013 to 2017 (χ2 =33.294, P<0.001). Keratoconus remained in third place, but the proportion of PKP increased from 2013-2017 compared to 2005-2010 (χ2 =6.061, P=0.014). The proportion of herpes keratitis decreased from the second causes during 2005-2010 to the fourth causes during 2013-2017 (χ2 =6.397, P=0.011). Conclusion: Suppurative keratitis was the leading causes of PKP at Qingdao Eye Hospital from 2013 to 2017, followed by regraft, keratoconus and herpes keratitis. Compared to 2005-2010, the proportions of regraft and keratoconus increased significantly in 2013-2017 at Qingdao Eye Hospital, while the proportion of herpes keratitis decreased.

Objective: To compare the static cyclotorsion component (SCC) identification success rate with Femtosecond laser-assisted in situ keratomileusis (FS-LASIK). Methods: In this prospective study, a total of 205 patients (410 eyes) agreed to undergo corneal refractive surgery in Affiliated BenQ Hospital of Nanjing Medical University from July to September 2017. The study included 366 eyes of 183 patients undergoingFS-LASIK as the experimental group and 44 eyes of 22 patients undergoing transepithelial photorefractive keratectomy (TransPRK) as the control group. The 366 eyes undergoing FS-LASIK surgery were divided into a pre-lifting-flap measurement group (130 eyes), a post-lifting-flap measurement group (126 eyes) and a post-lifting-flap recovery measurement group (110 eyes) according to the SCC identification time. Chi-square test was used to analyze the differences in the success rates of SCC in different groups. An independent t test and variance analysis were used to analyze the differences in SCC degrees in different groups. Results: The overall SCC identification success rate was 77.3%. The success rates of the FSLASIK group (366 eyes) and TransPRK group (44 eyes) were 74.9% (274 eyes) and 97.7% (43 eyes), respectively (χ²=11.71, P<0.001). Gender did not have a statistically significant difference on the success rate of SCC. The success rate for right eyes was 82.4% and left eyes was 72.2% (χ²=6.13, P=0.013). The success rates in the pre-lifting-flap measurement group, the post-lifting-flap measurement group and the post-lifting-flap recovery measurement group were 63.8%, 84.1% and 77.3%, respectively (χ²=14.47, P<0.001). Average SCC degree for all subjects was 3.0°±2.3°. There was no statistically significant difference for gender or either eye (right or left). The means for the SCC degrees were 3.1°±2.4° in FSLASIK and 2.2°±1.7° in TransPRK (t=1.99, P=0.007). There was no statistically significant difference in the SCC value between the pre-lifting-flap, the post-lifting-flap and the post-lifting-flap recovery. An SCC greater than 2° accounted for 59.3% of the eyes, greater than 4° accounted for 28.7% and greater than 6° accounted for 9.2%. Conclusion: Measurement after lifting the flap can effectively improve the success rate of SCC identification.

Objective: To study health-related quality of life (HRQOL) in adult strabismus patients with successful corrective surgery outcomes, and to evaluate the factors associated with the status of post-operative HRQOL. Methods: In this retrospective case-control study, 92 adults who underwent corrective surgery during January to December 2011 and were followed for at least 1 year from Eye Hospital, Wenzhou Medical University were recruited; HRQOL was evaluated before and after surgery using the Chinese version of the Adult Strabismus 20 (CAS-20). Demographics and clinical characteristics were recorded. Eighty-nine cases of age-matched normal people without a history of strabismus were recruited from the general population as the control group. A Wilcoxon signed-rank test, independent t test, paired t test, and ANOVA were used to evaluate the difference in the CAS-20 scores. A multivariate analysis ofvariance was used to study the relationship between postoperative outcomes and demographics based on CAS-20 scores. Results: The CAS-20 scores of the 92 patients improved significantly after surgery in the psychosocial subscale (Z=3.25, P=0.001), function subscale (Z=3.19, P=0.001) and total scale (Z=3.60, P=0.001). Subjects who had better recovery of stereo function (F=4.33, P=0.016) and fusion function (Z=2.60, P=0.009) had better HRQOL than those who did not recover. HRQOL was better in the 68 subjects who did not believe there was a deviation than those 24 cases who believed there was still a deviation (Z=3.69, P<0.001). Postoperative HRQOL was also worse (Z=11.23, P<0.001) in patients than in the normal controls, with approximately 32% of subjects having scores within the normal threshold. The belief that there was no ocular deviation was the significant factor associated with postoperative HRQOL status. Conclusions: HRQOL improved in adults with a successful surgical outcome but was still worse than the general population when evaluated by CAS-20. Subjects who recovered binocular vision had better HRQOL. A belief that there was good alignment was the main factor that correlated with better postoperative HRQOL status.

Intermittent exotropia is a common form of divergent strabismusin children. The incidence of intermittent exotropia is in addition to comitant exotropia. Although it has been studied extensively, the pathogenesis, mechanism, and the indication for and timing of intervention remain unclear. This article reviews the most recent research surrounding the disease classification: Presentation, binocular vision and control in intermittent exotropia.