Cycloplegic autorefraction versus subjective refraction: the Tehran Eye Study.

AIM: To compare cycloplegic autorefraction with non-cycloplegic subjective refraction across all age and refractive error groups. METHODS: In a cross-sectional study with random stratified cluster sampling, 160 clusters were chosen from various districts proportionate to the population of each district in Tehran. Following retinoscopy and autorefraction with the 0.25 D bracketing (Topcon KR-8000, Topcon, Tokyo, Japan), all participants had a subjective refraction. Then all participants underwent cycloplegic autorefraction. RESULTS: The final analysis was performed on 3482 participants with a mean age of 31.7 years (range 5-92 years). Based on cycloplegic and subjective refraction, mean spherical equivalent (SE) was +0.31±1.80 and -0.32±1.61 D, respectively (p<0.001). The 95% limits of agreement (LoA) between these two types of refraction were from -0.40 to 1.70 D. The largest difference between these two types of refraction was seen in the age group of 5-10 years (1.11±0.60 D), and the smallest difference was in the age group of >70 years (0.34±0.45 D). The 95% LoA was -0.52 to 0.89 D in patients with myopia and -0.12 to 2.04 D in patients with hyperopia. We found that female gender (coefficients=0.048), older age (coefficients=-0.247), higher education (coefficients=-0.043) and cycloplegic SE (coefficients=-0.472) significantly correlated with lower intermethod differences. CONCLUSIONS: The cycloplegic refraction is more sensitive than the subjective one to measure refractive error at all age groups especially in children and young adults. The cyclorefraction technique is highly recommended to exactly measure the refractive error in momentous conditions such as refractive surgery, epidemiological researches and amblyopia therapy, especially in hypermetropic eyes and paediatric cases.

The location of incision in cataract surgery and its impact on induced astigmatism.

PURPOSE OF REVIEW: The purpose of the present study is a systematic review of previous studies on choosing the best incision site for the correction of astigmatism in cataract surgery and assessing the amount of surgically induced astigmatism (SIA) with each approach. RECENT FINDINGS: Regardless of astigmatism axis, studies show that using an on-axis incision is associated with favorable results for 0.5-1.0 diopter (D) of astigmatism. In cases with more than 1.0 D astigmatism, paired on-axis incisions can be appreciably efficient in astigmatism correction and cause at least 1.5 D SIA. Considering the amount of SIA, a temporal incision is the best approach when the patient has minimal amounts of corneal astigmatism preoperatively. At higher levels of astigmatism, if no other astigmatism correction method is used simultaneously, the temporal incision is used less frequently; however, since it is associated with the least SIA, it is still the choice site when another correction method is used. SUMMARY: The temporal incisions in cataract surgery are associated with little SIA and are appropriate choices for mild preoperative astigmatism. At higher levels of preoperative astigmatism, superior incisions are associated with better results when combined methods are not applied.

Cataract Surgical Rate between 2006 and 2010 in Tehran Province.

BACKGROUND: 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. METHODS: 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. RESULTS: 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, hospitalization for one night or more had a decreasing trend from 2006 to 2010. CONCLUSION: During 2006-2010, the CSR was acceptable in Tehran in comparison with other studies. However, attention should be paid to the increase in the population of the elderly people. Although more than 95% of the surgeries in the Province of Tehran are performed using the phacoemulsification method, the rate should increase to 100% in the eligible cases.

The Prevalence and Causes of Visaual Impairment and Blindness in a Rural Population in the North of Iran.

BACKGROUND: Visual impairment is a very important public health problem. In Iran, reports of visual impairment and blindness have been published from the urban population while the prevalence of visual impairment in the rural population has not been reported. The purpose of this study to determine the prevalence and causes of visual impairment, in a rural population in district of based on age and sex. METHODS: In a cross-sectional population-based study, using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Eye examinations were performed in a Mobile Eye Clinic (Nooravaran Salamat, 2011) and included optometric examinations such as measuring uncorrected and corrected visual acuity along with non-cycloplegic refraction. RESULTS: The prevalence of visual impairment, low vision, and blindness was 6.3% (95% CI 5.3-7.3), 3.4% (95% CI 2.6-4.1), and 3.0% (95% CI 2.3-3.6), respectively. The prevalence of visual impairment ranged from 1.8% in the participant younger than 20 years of age to 28% in the subjects aged 60 and over (P<0.001). After matching for age, the prevalence of visual impairment and low vision was significantly higher in women. The most prevalent causes of visual impairment were uncorrected refractory error (54.5%) and cataract (17.6%). CONCLUSION: The prevalence of visual impairment was significantly higher in the rural population of this study when compared to previous reports from Iran. It seems that provision of therapeutic facilities like cataract surgery and availability of eyeglasses in villages can considerably reduce the prevalence of visual impairment.

Ionizing radiation-induced cataract in interventional cardiology staff.

BACKGROUND: The use of ionizing radiation has led to advances in medical diagnosis and treatment. OBJECTIVES: The purpose of this study was to determine the risk of radiation cataractogenesis in the interventionists and staff performing various procedures in different interventional laboratories. PATIENTS AND METHODS: This cohort study included 81 interventional cardiology staff. According to the working site, they were classified into 5 groups. The control group comprised 14 professional nurses who did not work in the interventional sites. Participants were assigned for lens assessment by two independent trained ophthalmologists blinded to the study. RESULTS: The electrophysiology laboratory staff received higher doses of ionizing radiation (17.2 ± 11.9 mSv; P < 0.001). There was a significant positive correlation between the years of working experience and effective dose in the lens (P < 0.001). In general, our findings showed that the incidence of lens opacity was 79% (95% CI, 69.9-88.1) in participants with exposure (the case group) and our findings showed that the incidence of lenses opacity was 7.1% (95% CI:2.3-22.6) with the relative risk (RR) of 11.06 (P < 0.001). CONCLUSIONS: We believe that the risk of radiation-induced cataract in cardiology interventionists and staff depends on their work site. As the radiation dose increases, the prevalence of posterior eye changes increases.

The prevalence of strabismus in 7-year-old schoolchildren in Iran.

PURPOSE: To determine the prevalence of tropia and phoria in Iran and their association with some related factors. METHODS: In a cross-sectional population-based study, multistage randomized cluster sampling was used to select participants from among grade 1 students in the primary schools of 7 cities of Iran. After obtaining their parents' approval, the students underwent the measurement of uncorrected and corrected visual acuity, cycloplegic refraction, and cover test. Distant and near cover test were performed at 6 m and 40 cm, respectively, with the best corrected visual acuity. Tropia and phoria were measured separately. RESULTS: Of 4157 selected students, 3675 participated in the study. The prevalence of strabismus was 1.68% (95% CI 1.13-2.23). The prevalence of strabismus was 2.17% (95% CI 1.06-3.29) in boys and 1.27% (95% CI 0.57-1.96) in girls (p = 0.216). Moreover, 1.27% (95% CI 0.82-1.72) of the children had exotropia and 0.44% (95% CI 0.22-0.65) had esotropia. The prevalence of constant and intermittent strabismus was 0.73% (95% CI 0.26-1.19) and 0.96% (95% CI 0.55-1.36), respectively. Phoria was detected in 32.98% (95% CI 24.25-41.71) of the children in this study. The prevalence of residual amblyopia was 23.77% (95% CI 9.45-38.08) in strabismic and 1.43% (95% CI 0.09-1.96) in non-strabismic children (p < 0.001). The odds of strabismus were significantly higher in hyperopic and astigmatic children. CONCLUSION: This study showed the prevalence of tropia and phoria across Iran. Exotropia was the most common type of tropia in Iran and intermittent strabismus was the most common type of strabismus. Due to prevalent amblyopia in strabismus, attention should be directed toward careful screening and treatment.

In a double-blind, randomized and placebo-controlled trial, adjuvant allopurinol improved symptoms of mania in in-patients suffering from bipolar disorder.

Allopurinol is a drug used primarily to treat hyperuricemia. In patients suffering from acute mania, increased levels of uric acid are observed, and symptom improvements are associated with decreased levels of uric acid. Accordingly, a purinergic dysfunction is plausibly a causative factor in the pathophysiology of mania. The aim of the present study was therefore to investigating whether allopurinol has benefits for patients treated with sodium valproate during acute mania. (Background) A double-blind, placebo-controlled study lasting 4 weeks was performed. The intention-to-treatment population included 57 patients; 50 concluded the study per protocol. Patients suffering from BPD and during acute mania were randomly assigned either to a treatment (sodium valproate 15-20 mg/kg+300 mg allopurinol twice a day) or to a control condition (sodium valproate 15-20 mg/kg+placebo). Experts rated illness severity and illness improvements (Clinical Global impression), and extent of mania via the Young Mania Rating scale. Uric acid levels were assessed at the beginning and end of the study. (Experimental procedures) Compared to the control group, symptoms of mania decreased significantly over time in the treatment group. Uric acid levels declined significantly in the treatment as compared to the control group. Probability of remission after 4 weeks was 23 times higher in the treatment than the control group. Lower uric acid levels after 4 weeks were associated with symptom improvements. (Results) The pattern of results from this double-blind, randomized and placebo-controlled study indicates that adjuvant allopurinol leads to significant improvements in patients suffering from acute mania (Conclusion).

Effect of living in lead mining area on growth.

OBJECTIVE: Blood lead level BLL and growth parameters including weight and height, in children, living in lead mining area was surveyed. METHODS: Two groups of 7-11 yr old children, including 45 from a lead mining area (Angooran-Zanjan Province-Iran) and 36 from control area (similar area to the study area, but not lead mining: Ijrood--the same province), were selected to assess BLL (by atomic absorption spectrometry) and growth parameters. RESULTS: In the children of the study and control areas, mean BLLs were 36.97+/-24.67 (microg/dL; mean +/- SD) and 15.57 +/- 13.35 (microg/dL; mean+/-SD), respectively (P=0.0005). No significant correlation was found between BLL in children and their fathers' occupation. In addition, there was no significant difference in growth parameters, including weight and height, in the children of two groups. CONCLUSION: Regarding the results of this study, environmental exposure due to living in lead mining area can lead to increased BLL in children. In addition, our results suggest there is no significant effect of BLL on growth parameters in children in lead mining area. Since some clinical and sub clinical problems are strongly probable when BLL is increased, special attention of the relevant organizations and more research about the problem and its outcome, is recommended.