Farhad Rezvan

The purpose of this study was to test the measurements of a multifunctional device, the NIDEK OPD-Scan III in terms of repeatability and agreement with retinoscopy and Pentacam in cases with emmetropia, ametropia, and KCN (grade 1-3). We enrolled 170 eyes (40 in each group of emmetropia and ametropia, and 90 in the 3 KCN subgroups). Acquisitions were done twice by a single technician to check the intra class correlation, repeatability index, and precision. To assess agreement, we compared OPD-Scan III with retinoscopy and Pentacam results by two blinded technicians. All device functions had acceptable precision in groups with emmetropia, ametropia, and KCN1, except spherical error in ammetropics (0.97 D). In KCN2, repeatability was acceptable with the refractive function, topography, and ocular aberrations but was more than 1.0 D for corneal aberrations. In KCN3, repeatability was low for the refractive function and corneal spherical aberration. Refractive data were not convertible to those obtained by retinoscopy in any group. OPD-Scan III keratometry data were interchangeable with Pentacam counterparts in emmetropes, ammetropes, and KCN1. In KCN2, the OPD-Scan III-Pentacam agreement for Kmax was 0.71 D, and there was 1.25 D difference in Kmin. No OPD-Scan III-Pentacam agreement was observed in KCN3. OPD- Scan III is a multifunctional device with acceptable repeatability in emmetropic, ammetropic, and KCN cases. Its measurements of corneal curvature and ocular aberrations are better than other functions. In cases with high degrees of refractive error and corneal irregularities, device repeatability and agreement with Pentacam is decreased.

Refractive errors are a common eye problem. Considering the low number of population-based studies in Iran in this regard, we decided to determine the prevalence rates of myopia and hyperopia in a population in Mashhad, Iran. Cross-sectional population-based study. Random cluster sampling. Of 4453 selected individuals from the urban population of Mashhad, 70.4% participated. Refractive error was determined using manifest (age > 15 years) and cycloplegic refraction (age ≤ 15 years). Myopia was defined as a spherical equivalent of -0.5 diopter or worse. An spherical equivalent of +0.5 diopter or worse for non-cycloplegic refraction and an spherical equivalent of +2 diopter or worse for cycloplegic refraction was used to define hyperopia. Prevalence of refractive errors. The prevalence of myopia and hyperopia in individuals ≤ 15 years old was 3.64% (95% CI: 2.19-5.09) and 27.4% (95% CI: 23.72-31.09), respectively. The same measurements for subjects > 15 years of age was 22.36% (95% CI: 20.06-24.66) and 34.21% (95% CI: 31.57-36.85), respectively. Myopia was found to increase with age in individuals ≤ 15 years and decrease with age in individuals > 15 years of age. The rate of hyperopia showed a significant increase with age in individuals > 15 years. The prevalence of astigmatism was 25.64% (95% CI: 23.76-27.51). In children and the elderly, hyperopia is the most prevalent refractive error. After hyperopia, astigmatism is also of importance in older ages. Age is the most important demographic factor associated with different types of refractive errors.

ABSTRACT Purpose To determine the prevalence of binocular anomalies among preschool children in Mashhad, Iran Methods In a cross-sectional study with random cluster sampling, children aged 4 to 6 years old from kindergartens of Mashhad in Iran were selected. Examinations included: visual acuity, objective and subjective refractions, cover test, near point of convergence and stereopsis. Best corrected visual acuity worse than 8/10 or more than two Snellen lines difference between the eyes was defined as amblyopia. Anisometropia was defined as spherical equivalent refraction difference of 1.0 diopter and more between two eyes. Results Of the 3765 selected children, 98.3% of them participated in the study. The mean age of the subjects was 5.09 (range: 4-6) years and 51.3% of them were boys. Strabiamus was found in 1.2 % of the children and intermittent exotropia had the highest prevalence. Prevalence of amblyopia and anisometropia were 0.5% and 6% respectively. Heterophoria was found in 62.7% and shift was toward esophoria.The mean near point of convergence was 5.09 ± cm. Stereopsis of 100 sec/arc and better was found in 94.6% of the subjects. Conclusion The results of this study indicated that the prevalence of strabismus was similar to other studies in Iran while there was a smaller prevalence of amblyopia. For preventing the incidence of binocular anomalies in children, a careful planning of the basic information is required to check the status of binocular vision.

To determine intraoperative complications of cataract surgery over the period 2006 to 2010. In this cross-sectional study, 106 of 272 cataract surgical centers in Iran were selected through multistage random cluster sampling from all provinces. In each province, the selected number of centers was proportionate to the number of cataract surgeries, and in each center, the selected number of charts was proportionate to the center's number of cataract surgeries, from which we retrieved intraoperative complications. The prevalence of intraoperative complications of cataract surgery was 5.04% (95% confidence interval, CI, 3.53-6.54%) in 2006, which decreased significantly to 3.44% (95% CI 1.84-5.04%) in 2010. The most common complication was posterior capsular rupture/vitreous loss which decreased from 4.29% (95% CI 2.93-5.66%) in 2006 to 2.81% (95% CI 1.3-4.31%) in 2010. The next most common complication was suprachoroidal hemorrhage at 0.56% (95% CI 0.25-0.87%) in 2006 and 0.46% (95...

Considering population aging in Iran and the importance of cataract surgery in the old age, this study was performed to show the cataract surgical rate (CSR) between 2006 and 2010 in Tehran Province. Eighteen centers were randomly selected from cataract surgery centers in Tehran. In each center, one week in every season was randomly selected and the number of cataract surgeries in the week was calculated. In total, 20 weeks were selected in each center in five years. The CSR increased linearly from 8011 cases per 1,000,000 population in 2006 to 12465 cases per 1,000,000 population in 2010. As for patients below 40 years of age, the percentage of the male patients was more while after the age of 40 years, the percentage of the female patients was more in all age groups. At least 96.2% of the surgeries in each year were performed using the phacoemulsification method. From 2006 to 2010, the percentage of outpatient surgery increased from 48.7% to 72.5%. On the other hand, hospitalizati...

Purpose: To determine the prevalence of refractive errors and their determinants among the elderly in Sari, in the north of Iran. Methods: Random clustering sampling was used to determine the elderly aged 55 or over for a population-based study. All participants underwent complete eye examinations including objective and subjective refractions, actual and optimal visual acuities, biomicroscopy, funduscopy, tonometry and visual field testing. Myopia and hyperopia were defined as spherical equivalent (SE) < -0.50 dioptrs (D) and >+0.50 D respectively. Astigmatism was defined as a cylindrical power worse than -0.50D. Anisometropia was defined as different in SE between two eyes >1.0. Results: Of the 1185 selected participants, 79.1% participated in the study. The mean age of the subjects was 64.7 (range 55-87) years and 53.6% of them were females. According to the age and sex standardised, the prevalence of myopia, hyperopia, astigmatism and anisometropia were 19.7% (95% confi...

Purpose The purpose of this study was to determine the prevalence of eye diseases among the elderly in the city of Sari in northern Iran. Method In a cross-sectional population-based study by random cluster sampling, subjects older than 54 years old from the city of Sari in northern Iran were selected. Ophthalmic examinations included: vision, subjective and objective non-cycloplegic refractions, visual acuity, slit lamp biomicroscopy, intraocular pressure measurement, clinical grading of lens opacities, measurement of vitreous opacities, and direct and indirect ophthalmoscopy. Results Of 1185 selected subjects, 79.1% of them participated in the study. The results of this study showed that the prevalence of cataract, age related macular degeneration (AMD), glaucoma and diabetic retinopathy were 29.6% (95%CI: 26.6-32.5), 5.8% (95%CI: 4.3-7.3), 3.7% (95%CI: 2.5-5) and 2.7% (95%CI: 2.6-3.7) respectively. The prevalence of AMD was correlated to the male gender signifi cantly. These resu...

To determine the distribution of the cataract surgical number per million population per year (CSR), the CSR in the population older than 50 years (CSR 50+) in the provinces of Iran, and their economic inequality in 2010. As part of the cross-sectional 2011 CSR survey, the provincial CSR and CSR 50+ were calculated as the total number of surgeries in major and minor centers divided by the total population and the population older than 50 years in each province. Economic inequality was determined using the average province income, the average urban and rural household incomes, and the percentage of urban and rural population in each province. Tehran and Ilam provinces had the highest and lowest CSR (12,465 vs. 359), respectively. Fars and Ilam provinces had the highest and lowest CSR 50+ (71,381 vs. 2481), respectively. Low CSR (<3000) was detected in 9 provinces where 2.4 to 735.7% increase is needed to reach the minimum required. High CSR (>5000) was observed in 14 provinces (45.2%) where rates were 0.6 to 59.9% higher than the global target. Cataract surgical rate increased at higher economic quintiles. Differences between the first, second, and fifth (poorest) quintiles were statistically significant. The CSR concentration index was 0.1964 (95% confidence interval, 0.0964 to 0.2964). In line with the goals of the Vision 2020 initiative to eliminate cataract blindness, more than 70% of geographic areas in Iran have achieved the minimum CSR of 3000 or more. However, a large gap still exists in less than 30% of areas, mainly attributed to the economic status.

To determine the cataract surgical rate (CSR) between 2006 and 2010 in Iran. In this cross-sectional study, sampling was done from surgical centers throughout Iran. Centers throughout all of Iran with more than 3000 surgeries per year were grouped as major centers and the rest were grouped as minor centers. All major centers and a percentage of minor centers were selected from each province. For each center, we determined the number of cataract surgeries in a random week of each season. Of the 237 eligible surgical centers, 124 were selected and 106 were enrolled in the study; 80 were major centers and 26 were minor centers. The number of surgeries has increased from 335,948 in 2006 to 475,526 in 2010. Cataract surgical rate has increased from 4723 (95% confidence interval, 4707 to 4739) per million population in 2006 to 6328 (95% confidence interval, 6309 to 6346) per million population in 2010. In the 50 and older population, CSR was 38,450 per million population in 2010. Average annual number of cataract surgeries per surgeon was 263 in 2006 and 339 in 2010. Compared with previous studies, the 2006 to 2010 CSR in Iran is on an ascending trend. Also, our numbers are higher than the minimum recommended by the World Health Organization, although lower than that in Western countries. Considering the aging population of the country, the observed rate is not sufficient for all cases of cataract in the future, and there is a need to increase CSR throughout the nation.

To compare the best-corrected visual acuity (BCVA), vision-related quality of life (VRQoL), comfort, foreign body sensation in the eye, tolerance, and handling of ClearKone-Synergeyes hybrid contact lenses and rigid gas-permeable (RGP) lenses in patients with keratoconus. This comparative case series was conducted between 2011 and 2012 on 40 keratoconic patients (20 in each group). The BCVA of each patient was evaluated on the same day when the lens was prescribed. The National Eye Institute Visual Functioning Questionnaire (NEI-VFQ 25) questionnaire was assessed in addition to other subjective criteria 2 months after the lens prescription. The BCVA did not show a significant difference between the two lenses. Of the subjective criteria, the scores of the domains of general vision (P=0.008), ocular pain (P<0.001), distance activity (P=0.008), mental health (P<0.001), role difficulty (P<0.001), dependency (P=0.016), driving (P=0.067), total score of the NEI-VFQ 25 questionnaire (P<0.001), and comfort (P<0.001) were significantly higher in the ClearKone-Synergeyes group when compared with the RGP group. Foreign body sensation was statistically higher with RGP lens versus the ClearKone-Synergeyes lens (P=0.013). Regarding tolerance, the preference of the ClearKone-Synergeyes lens over the RGP lens was borderline (P=0.085). Although the BCVA did not differ significantly between the two lenses and both corrected vision to the same extent, satisfaction and VRQoL was better in keratoconic patients who used the ClearKone-Synergeyes lens in comparison with the RGP lens.

... Shiva Mehravaran a ,; Farhad Rezvan a ,; Sara Bigdeli a ,; Mehdi khabazkhoob a. a Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran; b Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran. Received 12 April 2011. ...

The prevalence of myopia and hyperopia and determinants were determined in a rural population of Iran. Population-based cross-sectional study. Using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Data from 2001 people over the age of 15 years were analysed. Visual acuity measurement, non-cycloplegic refraction and eye examinations were done at the Mobile Eye Clinic. The prevalence of myopia and hyperopia based on spherical equivalent worse than -0.5 dioptre and +0.5 dioptre, respectively. The prevalence of myopia, hyperopia and anisometropia in the total study sample was 28% (95% confidence interval: 25.9-30.2), 19.2% (95% confidence interval: 17.3-21.1), and 11.5% (95% confidence interval: 10.0-13.1), respectively. In the over 40 population, the prevalence of myopia and hyperopia was 32.5% (95% confidence interval: 28.9-36.1) and 27.9% (95% confidence interval: 24.5-31.3), respectively. In the multiple regression model for this group, myopia strongly correlated with cataract (odds ratio = 1.98 and 95% confidence interval: 1.33-2.93), and hyperopia only correlated with age (P < 0.001). The prevalence of high myopia and high hyperopia was 1.5% and 4.6%. In the multiple regression model, anisometropia significantly correlated with age (odds ratio = 1.04) and cataract (odds ratio = 5.2) (P < 0.001). The prevalence of myopia and anisometropia was higher than that in previous studies in urban population of Iran, especially in the elderly. Cataract was the only variable that correlated with myopia and anisometropia.

Purpose: To determine the incidence and determinants of intraoperative complications of cataract surgeries performed in Iran during 2000 to 2005 Methods: The Iranian Cataract Surgery Survey (ICSS) is a retrospective study in which random sampling was done from selected centers.

AimTo determine the prevalence of refractive errors among schoolchildren in urban and rural areas of Dezful County, Iran.MethodsIn a cross‐sectional study, using random cluster sampling, 5721 Dezful schoolchildren were selected from 39 clusters. The participants in the study totalled 5544; 3673 elementary and middle school students and 1871 high school students. For the former group, cycloplegic refraction and for the latter, non‐cycloplegic refraction was tested. In all participants, uncorrected visual acuity and best corrected visual acuity were determined, and those with a visual acuity of 20/40 or worse, underwent a complete ophthalmic examination to determine the cause of visual impairment. A spherical equivalent of −0.5 diopter (D) or worse was defined as myopia, +2.0 D or more was defined as hyperopia, and a cylinder refraction greater than 0.75 D was considered astigmatism.ResultsThe uncorrected visual acuity was 20/40 or worse in the better eye of 224 schoolchildren (3.8% o...

Purpose: To determine the association between astigmatism and spherical refractive error in a clinical population Methods: In this cross-sectional study, 2,000 patients who presented to our optometry clinic were enrolled. All were tested for objective refraction with a Nidek AR-310A auto refractometer, and non-cycloplegic refraction. For those under 15 years of age, cycloplegic refraction was measured as well. Myopia and hyperopia were defined as a spherical power of-0.5 Diopter (D) or less and+ 0.5 D or greater, respectively. Astigmatism ...

Purpose: To determine the prevalence of anisometropia and its determinants in the population of Mashhad. Methods: In a cross-sectional study in 2008, 4453 residents of Mashhad city between the ages of 1 and 90 years were selected using stratified cluster sampling, of which 70.4% participated in the study. All respondents had visual acuity and refraction testing. Anisometropia was defined as the absolute interocular difference in the spherical equivalent based on non-cycloplegic refraction. The prevalence rates and 95% ...

Purpose: The aim was to determine the agreement between PARK1 pachymetric readings and measurements made with the Pentacam and ultrasonic pachymetry. Methods: In this prospective study, we enrolled refractive surgery patients free of other ocular conditions and performed Pentacam and PARK1 acquisitions followed by ultrasonic pachymetry. We recorded pachymetric readings on the centre, apex and thinnest point with the Pentacam, corneal thickness values of the apex and minimum readings from the PARK1, and the ...

OBJECTIVES: A number of investigations have already been carried out to assess the effect of photodynamic therapy (PDT) on primary basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) lesions, but lack of investigations on recurrent lesions or lesions with treatment failure, prompted the authors to carry out this study. The aim of the present study was to evaluate the efficacy of photodynamic therapy on recurrent BCC and SCC lesions on head and neck skin. PATIENTS AND METHODS: A total of 30 patients, including 16 men ...

The aim of this study was to determine the trend of changes in Cataract Surgical Rate (CSR) in the provinces of Iran during 2006 to 2010 and identify high risk areas. This report is part of the national Iranian CSR Study. The percentage change in CSR in 2010 compared to 2006 was conducted in each province, retrospectively. One hundred and ten centers were chosen from all provinces, to determine CSR in each, the weight of major (>3,000 annual surgeries) and minor (3,000 annual surgeries or less) centers was calculated based on the number of selected centers, and multiplied by the number of surgeries in each province. In eight provinces, CSR was decreased by 1-60%. One province (Booshehr) showed no change. Eighteen provinces had 2-79% increase. No 2006 data was available in three provinces. North Khorasan had the most decrease while Kerman had the most increase in CSR. Six of these 8 provinces had CSR>3,000 despite a decrease in 2010, but North Khorasan had CSR<3,000 over the...

To determine the number of cataract surgeries per million population per year or the cataract surgical rate (CSR) in Iran for every year from 2000 to 2005 as part of the objectives of the Vision 2020 initiative by the World Health Organization (WHO) to eliminate cataract blindness. This study is part of the Iranian Cataract Surgery Survey, which was conducted as a retrospective cross-sectional study. All major cataract surgery centers and 10% of randomly selected minor centers throughout the nation were approached. Excluding the 2-week Iranian New Year holiday, 1 week per season between 2000 and 2005 (a total of 24 weeks) was selected for each center, and data concerning all cataract surgeries performed during these weeks were recorded by reviewing records of patients operated for cataracts. A total of 13,409 surgical records from 2000 to 2005 were evaluated, and CSR was calculated for each year based on the population data obtained from the Statistical Center of Iran. CSR showed an increasing trend in Iran, rising from 526 (95% confidence interval: 352 to 700) in year 2000 to 1331 (95% confidence interval: 1084 to 1577) in 2005. CSR has significantly increased in Iran in recent years but is still below the target suggested by WHO. Considering the age structure of the young population of Iran, the present CSR may suffice. However, it is necessary to implement plans to increase CSR and obviate obstacles to eliminating cataract blindness.

To estimate the prevalence and causes of severe visual impairment and blindness among children in Lorestan province of Iran, and to assess the feasibility of the Key Informant Method in this setting. Potential cases were identified using the Key Informant Method, in 3 counties of Lorestan province during June through August 2008, and referred for examination. Causes of severe visual impairment/blindness were determined and categorized using standard World Health Organization methods. Of 123 children referred for examination, 27 children were confirmed to have severe visual impairment/blindness or blindness. The median age was11 years (interquartile range 6-13), and 59% were girls. After adjusting for non-attenders, the estimated prevalence of severe visual impairment/blindness was 0.04% (0.03-0.05). The main site of abnormality was retina (44%), followed by disorders of the whole eye (33%). The majority of causes had a hereditary etiology (70%), which was associated with a family history of blindness (P = 0.002). Potentially avoidable causes of severe visual impairment/blindness were found in 14 children (52%). Almost all children with severe visual impairment/blindness had a history of parental consanguinity (93%). Our findings suggest a moderate prevalence of childhood blindness in the Lorestan province of Iran, a high proportion of which may be avoidable, given improved access to ophthalmic and genetic counselling services in rural areas. The Key Informant Method is feasible in Iran; future research is discussed.