The prevalence of refractive errors among adult rural populations in Iran

Purpose: The aim was to determine the prevalence of myopia and hyperopia and related factors in underserved rural areas in Iran. Methods: Under random cluster sampling, two rural regions were randomly selected in the north and southwest of the country, and 3,061 persons over 15 years of age were invited into the study. After selecting samples, all participants had refraction, measurement of uncorrected vision and visual acuity and ocular health examination by slitlamp biomicroscopy. Results: Of the 3,061 invitees, 2,575 participated in the study (response rate: 84.1 per cent). After excluding those who met the exclusion criteria or had missing refractive data, eventually there were 2,518 subjects available for this analysis. The mean age of the participants was 44.3 ± 17.5 years (range: 16 to 93 years) and 1,460 of them (58.0 per cent) were female. The overall prevalence of myopia and hyperopia in this study was 25.2 per cent (95 per cent CI: 23.2 to 27.2) and 22.5 per cent (95 per cent CI: 20.6 to 24.4), respectively. The prevalence of myopia increased from 20.9 per cent in participants 16 to 20 years to 32.9 per cent in the 21 to 30 years age group, declined up to the age of 60 years and increased again afterwards. The lowest prevalence was 6.8 per cent observed in the 16 to 20 years age group and the highest was 45.8 per cent in 61- to 70-year-olds. In the final logistic regression model, myopia significantly associated with age, higher education levels and cataracts, while hyperopia associated with age, lower education levels and male gender. Conclusion: In our study, the prevalence of myopia was lower and the prevalence of hyperopia was higher compared to most previous studies. The findings of this study imply that refractive errors vary by age. © 2017 Optometry Australi

Risk factors of regression and undercorrection in photorefractive keratectomy: A case-control study

�AIM: To determine risk factors of regression and undercorrection following photorefractive keratectomy (PRK) in myopia or myopic astigmatism. �METHODS: A case-control study was designed in which eyes with an indication for re-treatment (RT) were defined as cases; primary criteria for RT indication, as assessed at least 9mo postoperatively, included an uncorrected distance visual acuity (UDVA) of 20/30 or worse and a stable refraction for more than 3mo. Additional considerations included optical quality symptoms and significant higher order aberrations (HOAs). Controls were chosen from the same cohort of operated eyes which had complete post-operative follow up data beyond 9mo and did not need RT. The cohort included patients who had undergone PRK by the Tissue-Saving (TS) ablation profile of Technolas 217z100 excimer laser (Bausch & Lomb, Rochester, NY, USA). Mitomycin C had been used in all of the primary procedures. �RESULTS: We had 70 case eyes and 158 control eyes, and they were comparable in terms of age, sex and follow-up time (P values:0.58, 1.00 and 0.89, respectively). Pre-operative spherical equivalent of more than -5.00 diopter (D), intended optical zone (OZ) diameter of less than 6.00 mm and ocular fixation instability during laser ablation were associated with RT indications (all P values -5.00 D), smaller OZ (<6.00 mm) and unstable fixation during laser ablation of PRK for myopia and myopic astigmatism were found to be strong predictors of undercorrection and regression. © 2015 International Journal of Ophthalmology (c/o Editorial Office). All Rights Reserved

Effects of Computerized Decision Support Systems on Management of Atrial Fibrillation: A Scoping Review

Background: Potential role of computerized decision support system on management of atrial fibrillation is not well understood. Objectives: To systematically review studies that evaluate the effects of computerized decision support systems and decision aids on aspects pertaining to atrial fibrillation. Data sources: We searched Medline, Scopus and Cochrane database. Last date of search was 2016, January 10. Selection criteria: Computerized decision support systems that help manage atrial fibrillation and decision aids that provide useful knowledge for patients with atrial fibrillation and help them to self-care. Data collection and analysis: Two reviewers extracted data and summarized findings. Due to heterogeneity, meta-analysis was not feasible; mean differences of outcomes and confidence intervals for a difference between two Means were reported. Results: Seven eligible studies were included in the final review. There were one observational study without controls, three observational studies with controls, one Non-Randomized Controlled Trial and two Randomized Controlled Trials. The interventions were three decision aids that were used by patients and four computerized decision support systems. Main outcomes of studies were: stroke events and major bleeding (one article), Changing doctor-nurse behavior (three articles), Time in therapeutic International Normalized Ratio range (one article), decision conflict scale (two articles), patient knowledge and anxiety about stroke and bleeding (two articles). Conclusions: A computerized decision support system may decrease decision conflict and increase knowledge of patients with atrial fibrillation (AF) about risks of AF and AF treatments. Effect of computerized decision support system on outcomes such as changing doctor-nurse behavior, anxiety about stroke and bleeding and stroke events could not be shown.We need more studies to evaluate the role of computerized decision support system in patients with atrial fibrillation

A survey of attitudes, practices, and knowledge regarding drug-drug interactions among medical residents in Iran

Background When prescribing medications, physicians should recognize clinically relevant potential drug–drug interactions (DDIs). To improve medication safety, it is important to understand prescribers’ knowledge and opinions pertaining to DDIs. Objective To determine the current DDI information sources used by medical residents, their knowledge of DDIs, their opinions about performance feedback on co-prescription of interacting drugs. Setting Academic hospitals of Mashhad University of Medical Sciences (MUMS) in Iran. Methods A questionnaire containing questions regarding demographic and practice characteristics, DDI information sources, ability to recognize DDIs, and opinions about performance feedback was distributed to medical residents of 22 specialties in eight academic hospitals in Iran. We analyzed their perception pertaining to DDIs, their performance on classifying drug pairs, and we used a linear regression model to assess the association of potential determinants on their DDI knowledge. Main Outcome Measure prescribers’ knowledge and opinions pertaining to DDIs. Results The overall response rate and completion rate for 315 distributed questionnaires were 90% (n = 295) and 86% (n = 281), respectively. Among DDI information sources, books, software on mobile phone or tablet, and Internet were the most commonly-used references. Residents could correctly classify only 41% (5.7/14) of the drug pairs. The regression model showed no significant association between residents’ characteristics and their DDI knowledge. An overwhelming majority of the respondents (n = 268, 95.4%) wished to receive performance feedback on co-prescription of interacting drugs in their prescriptions. They mostly selected information technology-based tools (i.e. short text message and email) as their preferred method of receiving feedback. Conclusion Our findings indicate that prescribers may have poor ability to prevent clinically relevant potential DDI occurrence, and they perceive the need for performance feedback. These findings underline the importance of well-designed computerized alerting systems and delivering performance feedback to improve patient safety

Finite-size anisotropy in statistically uniform porous media

Anisotropy of the permeability tensor in statistically uniform porous media of sizes used in typical computer simulations is studied. Although such systems are assumed to be isotropic by default, we show that de facto their anisotropic permeability can give rise to significant changes of transport parameters such as permeability and tortuosity. The main parameter controlling the anisotropy is $a/L$, being the ratio of the obstacle to system size. Distribution of the angle $\alpha$ between the external force and the volumetric fluid stream is found to be approximately normal, and the standard deviation of $\alpha$ is found to decay with the system size as $(a/L)^{d/2}$, where $d$ is the space dimensionality. These properties can be used to estimate both anisotropy-related statistical errors in large-scale simulations and the size of the representative elementary volume.Comment: 7 pages, 9 figure

High prevalence of refractive errors in 7 year old children in Iran

Background: The latest WHO report indicates that refractive errors are the leading cause of visual impairment throughout the world. The aim of this study was to determine the prevalence of myopia, hyperopia, and astigmatism in 7 yr old children in Iran. Methods: In a cross-sectional study in 2013 with multistage cluster sampling, first graders were randomly selected from 8 cities in Iran. All children were tested by an optometrist for uncorrected and corrected vision, and non-cycloplegic and cycloplegic refraction. Refractive errors in this study were determined based on spherical equivalent (SE) cyloplegic refraction. Results: From 4614 selected children, 89.0 participated in the study, and 4072 were eligible. The prevalence rates of myopia, hyperopia and astigmatism were 3.04 (95 CI: 2.30-3.78), 6.20 (95 CI: 5.27-7.14), and 17.43 (95 CI: 15.39-19.46), respectively. Prevalence of myopia (P=0.925) and astigmatism (P=0.056) were not statistically significantly different between the two genders, but the odds of hyperopia were 1.11 (95 CI: 1.01-2.05) times higher in girls (P=0.011). The prevalence of with-the-rule astigmatism was 12.59, against-the-rule was 2.07, and oblique 2.65. Overall, 22.8 (95 CI: 19.7-24.9) of the schoolchildren in this study had at least one type of refractive error. Conclusion: One out of every 5 schoolchildren had some refractive error. Conducting multicenter studies throughout the Middle East can be very helpful in understanding the current distribution patterns and etiology of refractive errors compared to the previous decade. © 2016. Iranian Journal of Public Health. All Right Reserved

Psychometric assessment of the persian version of the revised convergence insufficiency symptom survey in young adults with convergence insufficiency

Purpose: To translate the Convergence Insufficiency Symptom Survey (CISS) to Persian and to assess its validity and reliability in a group of young adult Iranian patients with convergence insufficiency (CI). Methods: The questionnaire was translated in backward and forward phases. Face validity was measured using a 6-point scale (very weak, weak, moderate, good, very good, best), and a score of =4 for each item indicated an acceptable face validity. The content validity was assessed using three indices of relevancy, clarity, and comprehensiveness. Relevancy and clarity were checked for each item and for the whole scale using a 4-point scale (1-undesirable, 2-relatively desirable, 3-desirable, 4-completely desirable), and Item Content Validity Index (I-CVI) and Scale Content Validity Index (S-CVI) were calculated for the above indices. Comprehensiveness was measured at the scale level using a 4-point scale (1-incomprehensive, 2-relatively comprehensive, 3-comprehensive, 4-totally comprehensive), and S-CVI was calculated. The internal consistency and test-retest reliability were assessed using Cronbach's alpha coefficient and interclass correlation coefficient (ICC), respectively. To evaluate discriminant validity, CI was categorized into mild, moderate, and severe stages, and the mean overall CISS score was compared between these groups. Results: Thirty CI patients aged 18-34 years participated in this study. On face validity assessment, all items finally had a score of �4. As for relevancy and clarity, I-CVI was above 80 for all items, and S-CVI was 98.8 and 96.6, respectively. The S-CVI was 100 for comprehensiveness. The overall Cronbach's coefficient and ICC were 0.77 and 0.95, respectively. There was a significant difference in the overall score between the three severity groups. Conclusion: The Persian CISS is a valid and reliable tool for clinical and research applications. © 2020 Iranian Society of Ophthalmology. All rights reserved

Does astigmatism alter with cycloplegia?

Purpose To determine the effect of the cyclopentolate 1 on the cylindrical and spherical components of the refraction. Methods Three hundred seventy-five eyes of 195 subjects, including 74 males and 121 females, aged from 3 to 59 years were refracted before and 30 min after cyclopentolate 1 eye drop instillation. To compare cylindrical data, power vector analysis (J0 and J45 cross cylinder) was applied. Results A statistically significant difference between the J0 values of the noncycloplegic and cycloplegic refraction was revealed (P = 0.006) while the J45 values did not significantly differ. 95 limit of agreement for dry and cycloplegic values of the J0 and J45 were �0.22 to 0.25 and �0.19 to 0.20, respectively. Astigmatism difference was separately analyzed in emmetropic, myopic and hyperopic eyes. The J0 difference was significant (P = 0.014) only in hyperopic eyes. Spherical equivalent (SE) values in cycloplegic refraction were significantly more hyperopic than those yielded in dry refraction by mean difference of +1.16 ± 1.20 diopters (P &lt; 0.0001). Spherical equivalent difference (SED) values were negatively correlated with age. Conclusions Our findings indicated that cycloplegic drops caused a statistically significant shift in the �with the rule� and �against the rule� astigmatisms, although the oblique astigmatisms remained unaffected. Further research with larger sample sizes are needed to answer what mechanisms are involved in changing cylinder with cycloplegia. © 2016 Iranian Society of Ophthalmolog

Demographic profile, clinical, and topographic characteristics of keratoconus patients attending at a tertiary eye center

Purpose: To evaluate the demographic profile, clinical, and topographic characteristics of keratoconus (KCN) patients attending at a subspecialty eye hospital in Tehran, Iran. Methods: In this cross-sectional study, all patients who attended Noor Eye Hospital between March 2011 and March 2017 and had a diagnosis of KCN were identified, and the required number of patients was randomly selected. The following data were extracted from patient's records: age, sex, visual acuity, refraction, keratometry, pachymetry, and treatment procedures. The data of KCN laterality, severity, morphology, and cone location were also extracted by analyzing the corneal imaging maps. Results: The records of 1080 eyes of 540 patients were evaluated. The mean age of the participants was 31.04 ± 8.54 years (range, 13�63 years), and 69.3 of the patients were male. The highest and lowest frequency of KCN was seen in the age group 20�30 years and above 50 years, respectively. Bilateral KCN was detected in 93.3 95% confidence interval (CI): 91.68�94.75 of the subjects. 43.7% (95%CI: 32.88�54.48), 55.6% (95%CI: 44.73�66.38), and 0.8% (95%CI: 0.75�0.78) of the cases had nipple, oval, and globus cones, respectively. The cone was central in 52.1% (95%CI: 41.10�63.11), paracentral in 43.6% (95%CI: 36.13�51.04), and peripheral in 4.3% (95%CI: 00.76�7.86) of the cases. The frequency percentage of KCN according to severity was 15.2% (95%CI: 13.09�17.46), 56.4% (95%CI: 53.37�59.37), and 28.4% (95%CI: 25.75�31.21) for mild, moderate, and severe KCN, respectively. Among different parameters, only cone location had a significant association with age as the frequency of paracentral and peripheral cones increased with ageing (P = 0.002). Conclusions: The mean age of KCN patients in our study was higher than similar studies in other Asian countries. KCN was bilateral in most cases with an oval morphology and central cone location. Most of the patients had moderate to severe KCN. © 2019 Iranian Society of Ophthalmolog