Prevalence of high astigmatism in children aged 3 to 6 years in Guangxi, China.

PURPOSE: To investigate the prevalence and type of high astigmatism among children aged 3 to 6 years in Guangxi, a relatively undeveloped province in western China, and to examine the correlation between astigmatism and visual acuity. METHODS: Children aged 3 to 6 years in Nanning, the capital of Guangxi Province, participated in a population-based survey using a cluster random sampling technique. Eye examinations included autorefraction, visual acuity measurements, and assessments of the external eye, anterior segment, media, and fundus. Data for the right eyes were analyzed. RESULTS: Among the 2304 children examined, the overall prevalence of high astigmatism (≥1.25 diopters by noncycloplegic SureSight autorefraction) was 12.7% (95% confidence interval, 11.3 to 14.0%). The age-specific prevalences of high astigmatism in 3-, 4-, 5-, and 6-year-old children were 13.8, 13.2, 12.9, and 8.1%, respectively. The prevalence of high astigmatism did not vary with age or gender (p > 0.05). The majority of cases of high astigmatism were with-the-rule astigmatism (82.9%), followed by against-the-rule (12.6%) and oblique (4.5%) astigmatism. A linear correlation was found between astigmatism magnitude and visual acuity (logMAR acuity = 0.068 + 0.055 × astigmatism) in all participants. Multiple linear regression analysis further showed that the correlation of astigmatism with visual acuity was magnitude dependent (ß = 0.240). When with-the-rule astigmatism was used as a reference group, against-the-rule astigmatism (ß = 0.137) and oblique astigmatism (ß = 0.154) were closely correlated with visual acuity. CONCLUSIONS: High astigmatism was moderately prevalent among children aged 3 to 6 years in Guangxi Province. With-the-rule astigmatism was the dominant form of astigmatism. Magnitude- and orientation-dependent correlations of astigmatism with visual acuity were confirmed.

[Clinical study of phacoemulsification with NeoSoniX handpiece].

OBJECTIVE: To evaluate the outcomes of phacoemulsification with NeoSoniX handpiece. METHODS: It was a prospective random controlled clinical trial. Six hundred and fifty-nine cases (659 eyes) having phacoemulsification were prospectively comprised in this study. All cases were divided into two groups randomly. Group 1(NeoSoniX handpiece) include 317 cases. Group 2 (standard handpiece) include 342 cases. Preoperative measurements included best correct visual acuity (BCVA) and cataract grade according to the Emery classification. Intraoperative measurements included active power (AP) and effective phaco time (EPT). Postoperative measurements included BCVA and corneal edema. RESULTS: Grade I to III nuclear sclerosis, the AP was 3.53% +/- 1.76% with NeoSoniX and 3.84% +/- 1.93 % with standard handpiece, the EPT was (0.23 +/- 0.15) minutes and (0.25 +/- 0.19) minutes, respectively. There was no significant difference in the postoperative BCVA and cornea edema between the two groups. Grade IV or V nuclear sclerosis, the AP was 6.31% +/- 2.78 % with NeoSoniX and 9.45% +/- 4.17 % with standard handpiece, the EPT was (0.55 +/- 0.28) minutes and (0.83 +/- 0.44) minutes, respectively. There was significant difference in the postoperative 1 day BCVA and cornea edema between the two groups. There was significant difference in the postoperative 7 days BCVA and cornea edema between the two groups. CONCLUSIONS: Ultrasound energy consumption with NeoSoniX was significantly less than with US alone in emulsifying cataracts of optimum density and dense hard cataracts.

[Comparative study of gentamycin and povidone-iodine on eliminating the conjunctival bacteria].

OBJECTIVE: To study the efficacy of gentamycin, 0.5% povidone-iodine and 5.0% povidone-iodine in eliminating rate of positive conjunctival bacteria cultures and aqueous humor contamination, and to observe their adverse effects. METHODS: It was a comparative study. Three hundred patients (300 eyes) were randomized to three groups: gentamycin group, 0.5% povidone-iodine group and 5.0% povidone-iodine group. All patients received 1-day (6 times) topical application of 0.3% ofloxacin before surgery. Approximately 5 minutes before surgery, the conjunctival sac was irrigated with 5 - 8 ml gentamycin, 0.5% povidone-iodine or 5.0% povidone-iodine, correspondingly. Conjunctival cultures were obtained at the following time points: before receiving any topical medications; after application of 1-day topical 0.3% ofloxacin, before irrigating the conjunctival sac; immediately before surgery approximately 5 minutes after conjunctival sac irrigation and at the end of the surgery. Anterior chamber aspirates were obtained at the beginning of the surgery. Bacteria isolated were identified and antibiotic susceptibility was determined. The rate of positive conjunctival cultures among each group was compared and significance of the difference was tested with the Pearson chi-square test. RESULTS: Rate of positive conjunctival cultures before the conjunctival irrigation was 79.7%, 76.6% and 77.8% in the gentamycin group, 0.5% povidone-iodine group and 5.0% povidone-iodine group, respectively. The difference between these three groups was not statistically significant (chi2 = 0.28, P = 0.86). At the end of surgery, the rate of positive conjunctival cultures in these three groups was 11.7%, 8.3% and 6.3%, respectively. The difference between these three groups was also not statistically significant (chi2 = 1.74, P = 0.41). The average rate of anterior aqueous contamination was 4.9% and there was no significant difference among these three groups (P > 0.05). CONCLUSIONS: Both 0.5% povidone-iodine and 5.0% povidone-iodine using for irrigating conjunctival sac are safe. Gentamycin, 0.5% povidone-iodine and 5.0% povidone-iodine have similar effects on the reduction of the bacteria in conjunctival sac.

[Posterior continuous curvilinear capsulorhexis with optic capture of the posterior chamber intraocular lens in pediatric cataract].

OBJECTIVE: To assess the clinical effects of posterior continuous curvilinear capsulorhexis with optic capture of the posterior chamber intraocular lens in pediatric cataract. METHODS: Fifty-one cases (83 eyes) received posterior continuous curvilinear capsulorhexis with optic capture of the posterior chamber intraocular lens. Preoperative and postoperative visual acuity and refractive error were recorded. Intraoperative and postoperative complications were observed. The follow-up period was from 6 to 36 months. RESULTS: Implantation of optic capture of the posterior chamber intraocular lens was successfully performed in 75 eyes (90.4%). The mean postoperative best corrected distant visual acuity achieved 0.5 or better in 75 eyes (48.0%). No eyes with optic capture were found optic axis opaque. The major complications of optic capture were anterior chamber fibrous exudation, iris posterior synechia and lenticular precipitates. CONCLUSION: Optic capture of the posterior chamber intraocular lens is safe and effective in the treatment of pediatric cataract to posterior continuous curvilinear capsulorhexis especially in the prevention of secondary opacification from the visual axis.