Lanhua Wang

A simple and evolutional approach proven to recanalise the nasolacrimal duct obstruction

Aim: To evaluate a new approach of recanalisation of nasolacrimal duct obstruction (RC-NLDO) in the treatment of the nasolacrimal duct obstruction (NLDO) and chronic dacryocystitis. Methods: 583 patients with 641 eyes suffering from NLDO and chronic dacryocystitis were enrolled in this study. The RC-NLDO was performed in 506 eyes, with 135 eyes undergoing external dacryocystorhinostomy (EX-DCR) as controls. Patient follow-up for 54 months was evaluated by symptoms, dye disappearance test, lacrimal irrigation and digital subtraction dacryocystogram. The RC-NLDO was also performed in 12 rhesus monkeys for histopathological examination. Results: The clinical success rates were 93.1% in 506 cases of RC-NLDO and 91.11% in 135 cases of EX-DCR. The success rates for second surgery were achieved in 85.19% on RC-NLDO and 40.0% on EX-DCR. No major intra- or postoperative complications were observed in the RC-NLDO group. The mean operative duration was 12.5 min for RC-NLDO and 40.3 min for EX-DCR (p<0.001). A pathological study in rhesus monkeys demonstrated that the RC-NLDO wounded epithelium in nasolacrimal duct healed completely within 1 month without granulation tissue formation. Conclusion: The findings demonstrate that the RC-NLDO is a simple and effective approach proven to recanalise the obstructed nasolacrimal duct with a comparable success rate to EX-DCR.

Causes and five-year incidence of blindness and visual impairment in urban southern China: The Liwan Eye Study

PURPOSE We determined the causes and five-year incidence of blindness and visual impairment (VI) in an adult, urban Chinese population. METHODS Participants underwent a comprehensive eye examination at baseline in 2003 and then five years later. The World Health Organization (WHO) and United States (US) definitions were used to define incident blindness (WHO visual acuity [VA] < 20/400 in the better-seeing eye, US VA ≤ 20/200) and incident VI (WHO VA < 20/60-20/400, US VA < 20/40->20/200). RESULTS Among 1405 baseline participants, 924 (75%) of 1232 survivors (87.7%) participated in the 5-year follow-up. The incidences of VI and blindness were 5.38% (95% confidence interval [CI] 3.99% ∼ 7.07%) and 0.33% (95% CI 0.07% ∼ 0.95%), respectively, based on the WHO definition, and 9.85% (95% CI 7.96% ∼ 12.0%) and 1.42% (95% CI 0.76% ∼ 2.41%), respectively, based on the US definition. Incidence of blindness and VI (WHO definition) increased significantly with older age (P < 0.001) and poorer baseline presenting VA in the worse-seeing eye (P < 0.001). The leading cause of best-corrected VI (WHO definition) was cataract (64.6%), whereas the main causes of presenting VI were refractive error (40.4%) and cataract (38.4%). CONCLUSIONS The incidence of VI in urban Southern China is high. The major causes are unoperated cataract and undercorrected refractive error, reflecting the need for better surgical and refractive care, even in this urban setting.

Five-Year Incidence and Postoperative Visual Outcome of Cataract Surgery in Urban Southern China: The Liwan Eye Study

PURPOSE To determine the 5-year incidence and visual outcome of cataract surgery in an adult urban Chinese population. METHODS A comprehensive eye examination was performed at baseline and 5 years later on subjects participating in a population-based study. Incident cataract surgery was defined as having undergone surgery in either eye during the 5-year period. Postoperative visual impairment (PVI) was defined as visual acuity (VA) <6/18 based on both presenting VA (PVA) and best corrected VA (BCVA) in the operated eye. RESULTS Among the 1405 baseline participants, 75% (924) of survivors were seen at the 5-year follow-up visit. Forty-four returning participants (62 eyes) had undergone incident cataract surgery, an incidence of 4.84% (95% confidence interval [CI] = [3.53, 6.44]). Detailed medical and surgical records were available for 54/62 (87.1%) eyes, and of these, 5/54 (24.1%) had an immediate preoperative visual acuity ≤ 6/120. All recorded surgeries were performed at tertiary-level hospitals with phacoemulsification and foldable intraocular lens implantation. Those undergoing cataract surgery were more educated (P < 0.05) and had poorer baseline PVA in the worse-seeing eye (P < 0.001) than 54 persons with baseline PVA <6/18 due to cataract who had not had surgery. Among the 62 operated eyes, 22.6% (14/62) had PVI based on PVA and 9.6% (6/62) based on BCVA. CONCLUSIONS Despite somewhat lower incidence, outcomes of cataract surgery in urban southern China are comparable with developed countries and better than for rural China. In urban China, emphasis should be on improving access to surgery.

Cataract-Related Visual Impairment Corrected by Cataract Surgery and 10-Year Mortality: The Liwan Eye Study.

PURPOSE To assess 10-year mortality in people who had undergone cataract surgery with no residual visual impairment (VI) and those who had persistent VI due to cataract using a population-based cohort. METHODS The Liwan Eye Study is a 10-year longitudinal study commenced in 2003. According to the World Health Organization, presenting VI was defined as visual acuity less than 20/63 in the better-seeing eye. History of cataract surgery was defined as cataract surgery performed on either eye. Information on the date of surgery was recorded. Dates of death occurring between baseline and April 30, 2014 were obtained from the National Death Index data. Information on socioeconomic factors was obtained from questionnaire interviews. Cox proportional hazards regression models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS Fifty-nine participants had undergone cataract surgery without residual VI and 67 participants had persistent cataract-related VI. The 10-year mortality rate for participants who had undergone cataract surgery without residual VI was statistically significant lower than that in participants who had VI due to cataract based on log-rank test (32.2% vs. 64.2%; P = 0.002). This finding remained significant in the unadjusted Cox proportional hazards model (HR, 0.43; 95% CI, 0.25-0.74; P = 0.002). After adjusting for age, sex, history of diabetes, and hypertension, body mass index (BMI), education level, and personal income, participants with cataract surgery and no residual VI did not have a higher chance of survival than participants with persistent VI due to cataract (HR, 0.56; 95% CI, 0.26-1.20; P = 0.136). CONCLUSIONS Cataract-related VI corrected by cataract surgery was not associated with better survival after adjusting for a number of possible confounders. Given our sample size is relatively small and limited power, further studies with larger sample are needed.

Perceived difficulty of various steps of manual small incision cataract surgery among trainees in rural China.

The perceived difficulty of steps of manual small incision cataract surgery among trainees in rural China was assessed.

Five-year visual outcome among people with correctable visual impairment: the Liwan Eye Study: Visual outcome of correctable visual impairment

Longitudinal data on visual outcome of correctable visual impairments (VI) are of paramount importance for decision‐maker to estimate burden and demand to treat avoidable VI.

Ten-year incidence of primary angle closure in elderly Chinese: the Liwan Eye Study

Purpose To determine the 10-year incidence of all forms of primary angle closure (PAC) in phakic eyes and its risk factors in an urban Chinese population aged 50 years and older. Methods Survivors of 1405 baseline participants were invited to attend the 10-year follow-up visit in the Liwan Eye Study. Participants with established baseline angle closure, including primary angle closure suspects (PACS), PAC and primary angle closure glaucoma (PACG), or those who underwent bilateral cataract surgery during the 10-year period, as well as those who did not tolerate gonioscopic examinations, were excluded from this analysis. Incident PAC was present when those with open angles at baseline developed angle closure in any form in either eye during the 10-year period. Results Among 791 participants who returned during the 10-year follow-up visit, 620 (78.4%) provided data on PAC incidence. The 10-year cumulative incidence of any forms of PAC was 20.5% (127/620, 95% CI 17.4% to 24.9%), including 16.9%, 2.4% and 1.1% with incident PACS, PAC and PACG in either eye, respectively. In multiple logistic regression, significant risk factors for incident angle closure were greater baseline lens thickness (OR=1.82 per mm, p=0.003), shallower anterior chamber depth (OR=3.18 per mm decreased, p=0.010) and narrower angle width (OR=1.63 per decreased angle width, p<0.0001). Conclusions Approximately one in five people aged 50 years and older developed some form of angle closure over a 10-year period. Small ocular dimensions and hyperopia at baseline were associated with the development of angle closure.

Prevalence of age-related macular degeneration in rural southern China: the Yangxi Eye Study

Purpose To describe the prevalence of age-related macular degeneration (AMD) among older adults in rural southern mainland China. Methods Eligible persons aged 50 years or over were identified by geographically defined cluster sampling from Yangxi County, Guangdong Province, China. Participants underwent a standardised interview and comprehensive eye examinations from August to November in 2014. Digital retinal photographs were graded for AMD lesions using the Clinical Classification of Age-Related Macular Degeneration developed by the Beckman Initiative for Macular Research Classification Committee. Age-standardised prevalence of AMD and AMD lesions was calculated using the 2010 world population data and compared with those of other populations. Results Of 5825 subjects who participated (90.7% response rate), 4881 (83.8%) had fundus photographs gradable for AMD. Early, intermediate and late AMD were present in 2003 (41.0%), 879 (18.0%) and 42 (0.86%) participants. The age-standardised prevalence of early, intermediate and late AMD was 40.4% (95% CI 39.6% to 41.2%), 17.6% (95% CI 17.0% to 18.2%) and 0.79% (95% CI 0.65% to 0.95%), respectively. Total AMD was more prevalent in men than in women (62.8% vs 57.1%). Conclusions AMD is an important public health concern for rural southern China, and the prevalence of AMD was higher in men than in women.

Novel system for distant assessment of cataract surgical quality in rural China

This study aims to assess the quality of various steps of manual small incision cataract surgery and predictors of quality, using video recordings.