Papers by javad heravian shandiz
Medical Hypothesis, Discovery & Innovation in Optometry, 2021
Background: Measuring contrast sensitivity (CS) allows a better understanding of the visual perfo... more Background: Measuring contrast sensitivity (CS) allows a better understanding of the visual performance of the human eye. This study aimed to examine the correlation and agreement between the results of two sinewave grating-based CS measurement methods, Metrovision and CSV-1000, in normal eyes. Methods: This cross-sectional, comparative study was performed between December 2018 and April 2019, at an optometry clinic. Subjects underwent comprehensive ocular examinations, which included pupil reflexes, subjective refraction, external eye examinations, smooth pursuit eye movement assessment, the cover–uncover test, and detailed slit-lamp examination of the anterior and posterior segments. Metrovision and CSV-1000 were employed to assess CS under photopic conditions. The correlation and agreement of the results of the two tests were evaluated. Results: CS was measured for 104 normal eyes for 3, 6, 12, and 18 cycles per degree (cpd) spatial frequencies (participants’ mean age ± standard ...
Journal of Ophthalmic and Vision Research, 2018
Purpose: To evaluate the enhancing effects of vision therapy on eye-hand coordination skills in s... more Purpose: To evaluate the enhancing effects of vision therapy on eye-hand coordination skills in students with visual impairments. Methods: Thirty-five visually impaired patients who underwent vision therapy comprised the treatment group, and 35 patients with impaired vision who received no treatment comprised the control group. Full ophthalmic examinations were performed, including biomicroscopy, retinoscopy, and assessments of subjective refraction and visual acuity. Eye-hand coordination was evaluated using the Frostig test. Vision therapy in the treatment group was performed using the Bernell-Marsden ball, perceptual-motor pen, random blink test, and random shape assessment. Results: Data were analyzed for the 35 visually impaired patients and 35 control participants. The mean age was 11.51 ± 3.5 and 11.09 ± 3.1 years in the treatment and control groups, respectively. Female participants comprised 80% of the treatment group and 57% of the control group. Before treatment, the mean scores on the Frostig test were 22.74 ± 4.32 and 21.60 ± 4.10 in the treatment and control groups, respectively, and after treatment, the mean Frostig test scores were 24.69 ± 3.99 and 21.89 ± 3.92, respectively. Statistically significant intergroup differences were found in eye-hand coordination (P < 0.05). No significant intergroup differences were noted in the distance and near visual acuity values. The results demonstrated that vision therapy could significantly improve eye-hand coordination, but no enhancement was found in near or distance visual acuity.
Acta Ophthalmologica, 2010
ABSTRACT Purpose To determine the prevalence and risk factors of refractive errors among schoolch... more ABSTRACT Purpose To determine the prevalence and risk factors of refractive errors among schoolchildren in Bojnourd, Iran.Methods In a cross-sectional study using random cluster sampling, 2020 schoolchildren 6 to 17 years of age were selected in this study. The participants totaled 1551; 643 boys and 908 girls of the elementary and middle schoolchildren of Bojnourd, northeast of Iran. Mean age of the participants was 11.2 years (response rate=76.7%). Refractive errors were measured under cycloplegia. Myopia defined as spherical equivalent (SE) refraction - 0.5 dioptre (D) or worse, hyperopia as SE +2.00 D or more, and astigmatism as cylinder -0.75 D or worse.Results The prevalence of myopia, hyperopia and astigmatism were 4.3%, 5.4% and 11.5% respectively and were not related to the gender. The prevalence of myopia and against-the-rule astigmatism increased with age (p&lt;0.001).Conclusion The results of this study showed that the prevalence of myopia in schoolchildren of Bojnourd was similar to that in most places excluding East Asian countries, and that of hyperopia and astigmatism were in the mid range.
Acta Ophthalmologica, 2010
Purpose To determine the prevalence of anisometropia, amblyopia and starbimus in schoolchildren o... more Purpose To determine the prevalence of anisometropia, amblyopia and starbimus in schoolchildren of Bojnourd, Iran. Methods A random cluster sampling was used in a cross-sectional study on 2020 schoolchildren in Bojnourd, northeast of Iran. The participants totaled 1551; 643 boys and 908 girls. Mean age of the partipiciants was 11.12 years (respose rate= 76.7%). Examinations included: uncorrected and best corrected visual acuity (UCVA and BCVA) measurements, cycloplegic refraction and cover test. Anisometropia ...
Acta Ophthalmologica, 2022
Ophthalmic and Physiological Optics, 2022
PURPOSE Under real-world conditions, tasks dependent on visual acuity may need to be performed in... more PURPOSE Under real-world conditions, tasks dependent on visual acuity may need to be performed in the presence of a mental load arising from concurrent, non-visual tasks. Therefore, measuring visual acuity concurrently with mentally demanding tasks may reflect a patient's vision more accurately. This study was designed to evaluate the impact of task-induced mental load on high contrast visual acuity, as measured using a letter chart and estimated via sweep visual evoked potentials (sweep VEP). METHODS Visual acuity was determined using the Freiburg Vision Test, and also using sweep VEP tested stepwise, from coarse to fine, over 13 spatial frequencies, in 31 healthy participants (aged 22.4 ± 3.6 years). Recordings were repeated while participants concurrently performed an auditory 2-back task. Mental load of the n-back task was confirmed through subjective ratings. RESULTS Visual acuity determined with the Freiburg Vision Test worsened from -0.02 ± 0.12 to 0.04 ± 0.15 logMAR under mental load (p = 0.03). Visual acuities estimated by sweep VEPs worsened from 0.38 ± 0.1 to 0.47 ± 0.1 logMAR (p < 0.001). While the slope of the VEP amplitude versus spatial frequency function steepened significantly with mental load (p = 0.01), VEP noise levels were not significantly affected (p = 0.07). CONCLUSION Visual acuity reduces significantly with a concurrent task that produces mental load. At least part of this reduction appears to be related to alterations in responses within the visual cortex, rather than being purely attributable to higher-level distraction effects.
Journal of Optometry, 2021
To compare the effect of full-correction versus under-correction on myopia progression. Methods: ... more To compare the effect of full-correction versus under-correction on myopia progression. Methods: A literature search was performed in PubMed, Scopus, Science Direct, Ovid, Web of Science and Cochrane library. Methodological quality assessment of the literature was evaluated according to the Critical Appraisal Skills Program. Statistical analysis was performed using Comprehensive Meta-Analysis (version 2, Biostat Inc., USA). Results: The present meta-analysis included six studies (two randomized controlled trials [RCTs] and four non-RCTs) with 695 subjects (full-correction group, n = 371; under-correction group, n = 324) aged 6 to 33 years. Using cycloplegic refraction, the pooled difference in mean of myopia progression was ---0.179 D [lower and higher limits: -0.383, 0.025], which was higher but not in full correction group as compared to under correction group (p = 0.085). Regarding studies using non-cycloplegic subjective refraction according to maximum plus for maximum visual acuity, the pooled difference in myopia progression was 0.128 D [lower and higher limits: -0.057, 0.312] higher in under-correction group compared with full-correction group (p = 0.175). Although, difference in myopia progression did not reach significant level in either cycloplegic or non-cycloplegic refraction. Conclusions: Our findings suggest that, myopic eyes which are fully corrected with noncycloplegic refraction with maximum plus sphere, are less prone to myopia progression, in comparison to those which were under corrected. However, regarding cycloplegic refraction, further studies are needed to better understand these trends.
future of medical education journal, 2017
Background and Objective: In general, understanding and willingness to act toward a certain thing... more Background and Objective: In general, understanding and willingness to act toward a certain thing is called the attitude toward that thing. Individuals� attitudes change in different periods of life according to their environment. One of the stages of life that has the most change of attitude and interest is the period of studying. This research was conducted to survey the attitude of optometric students about their field of study. Methods: This cross-sectional descriptive-analytical study was performed on all optometric undergraduate students at Mashhad University of Medical Sciences using a census method in the academic year of 2016-2017. Of the total of 88 students, 2 of them did not respond to the questionnaire. The data on a total of 86 people were gathered. The data gathering method was a questionnaire which had been evaluated for reliability and validity. Questionnaire questions were scored based on three-point Likert scale. Data were analyzed by SPSS version 22 using descr...
Introduction: The aim of present study was to assess the correlation between glucose and lipid bi... more Introduction: The aim of present study was to assess the correlation between glucose and lipid biomarkers variations with biometric characteristics and intraocular pressure changes following Ramadan fasting. Methods: A total of 100 healthy fasting volunteers were enrolled in the study. Of them, 89 subjects completed the study with respect to inclusion and exclusion criteria. Right eye ocular axial length and anterior chamber depth were determined using the IOLMaster, (Carl Zeiss Meditec, Jena, Germany). Following that, intraocular pressure of right eye was measured using a non-contact tonometer (Topcon, Computerized Tonometer CT-1/CT-1P, Tokyo, Japan). Blood samples were taken from all the participants and concentrations of the biomarkers, including Fast blood sugar, Triglyceride, Cholesterol, High-density lipoprotein and Low-density lipoprotein were measured using the Hitachi 717 analyzer (Hitachi, Tokyo, Japan). All assessments were obtained one week before and after Ramadan. Resu...
Reviews in Clinical Medicine, 2020
Introduction This study aimed to investigate the effect of phacoemulsification on macular thickne... more Introduction This study aimed to investigate the effect of phacoemulsification on macular thickness and volume in diabetic patients without retinopathy using optical coherence tomography (OCT).Methods This prospective study included 37 diabetics and 55 non-diabetic patients (n=92) with cataract who were scheduled for phacoemulsification. The participants were entered into the study based on the inclusion and exclusion criteria following a complete eye examination. Macular thickness and volume were measured preoperatively as well as one month postoperatively using the OCT (Spectralis; Heidelberg Engineering, Heidelberg, Germany).Results The present study analyzed 76 eyes of 76 patients with immature cataract. No significant differences were observed between diabetic and non-diabetic groups in terms of thickness and volume in the macular area. However, the results showed a significant increase in both groups regarding the thickness and volume after phacoemulsification. Conclusion The ...
Introduction: The present study aimed to assess the effects of Ramadan fasting on micronutrients ... more Introduction: The present study aimed to assess the effects of Ramadan fasting on micronutrients and their correlations with ocular biometry. Methods: This prospective study was conducted on 89 healthy volunteers (51 males and 38 females) with the mean of 34.98±9.10 years in Mashhad, Iran. Participants received complete ophthalmic and systemic examinations one week before and one week after the holy month of Ramadan in 2015. Subjects with no history of systemic and ophthalmic diseases were enrolled in the study. Blood samples were obtained from all the participants in the morning in both phases of the study. Levels of micronutrients were measured in the blood samples using the Hitachi 717 analyzer (Hitachi, Japan). In addition, IOLMaster (Carl Zeiss Meditec AG, Germany) was applied to determine the ocular axial length (AL) and anterior chamber depth (ACD). Results: No significant differences were observed in the AL and ACD of the subjects before and after Ramadan fasting (P>0.05)...
Journal of Current Ophthalmology, 2021
We thank Dr. Prousali Efthymia et al. for their perceptive comments on our research. Their letter... more We thank Dr. Prousali Efthymia et al. for their perceptive comments on our research. Their letter concerned primarily regarding the trend of choroidal thickness changes during childhood. The main objective of our study was to characterize the distribution of choroidal thickness profile in healthy Iranian children and adults at different age groups from 4 to 60 years old.1 The different kinds of refractive errors were labeled for each age group. The purpose of the study necessitated performing the examinations on a large sample of subjects from childhood to adulthood with different types of refractive errors. One limitation of our study was that we could not easily find a large number of children up to 10‐year‐old with different types of refractive errors to include in the study. However, considering the poor cooperation of children in the prolonged process of examinations and compared with previous studies, the number of pediatric subjects in the present study seems to be reasonable...
Introduction: This article aimed to review the literatures on visual impairments and ocular chang... more Introduction: This article aimed to review the literatures on visual impairments and ocular changes in premature infants with low birth weight and gestational age.Methods: Five electronic databases including: PubMed, Web of Science, Science direct, Ovid, and Scopus were searched. Original articles published until 2015 describing preterm infants were reviewed. Repetitive and derivative articles were excluded.Results: Out of 100 unique, potentially relevant articles, 42 studies that addressed and met the inclusion criteria were evaluated.Conclusion: Prematurity affects ocular structures (from anterior to posterior segment) and functions. Premature infants are at risk of myopization. Concerning the changes in premature infants, a significant increase is found in axial length, intraocular pressure, and central corneal thickness; moreover, high incidence of retinal changes is reported as a result of prematurity. On the other hand, visual acuity, tear, electroretinogram, and visual evoked...
Purpose The present study aimed to review the effect of dehydration during Ramadan fasting on the... more Purpose The present study aimed to review the effect of dehydration during Ramadan fasting on the health and ocular parameters leading to changes in eye function. Methods Articles included in the study were taken from PubMed, Ovid, Web of Science and Google Scholar up to 2014. Related articles were also obtained from scientific journals on fasting and vision system. Results Dehydration and nutrition changes in Ramadan cause an increase in tear osmolarity, ocular aberration, anterior chamber depth, IOL measurement, central corneal thickness, retinal and choroidal thicknesses, and also a decrease in IOP, tear secretion, and vitreous thickness. Conclusion Much research related to the effect of dehydration on ocular parameters during Ramadan fasting exists. The findings reveal association with significant changes on ocular parameters. Thus, it seems requisite to have a comprehensive study on "fasting and ocular parameters”, which will be helpful in making decisions and giving plan ...
Ocular Immunology and Inflammation, 2020
ABSTRACT Purpose: The purpose of this study is to assess the pooled prevalence of meibomian gland... more ABSTRACT Purpose: The purpose of this study is to assess the pooled prevalence of meibomian gland dysfunction (MGD) and evaluate its risk factors by gender, age, and ethnicity. Methods: Articles were searched reporting the prevalence of MGD from PubMed, Scopus, Web of Science, and Embase databases. Results: The estimated pooled prevalence of MGD was 0.358 (95% CI 0.26–0.46; I 2: 99.57%). The prevalence of MGD was 0.358 (95% CI 0.24–0.50) in clinical and 0.359 (95% CI 0.22–0.52) in population-based studies. Men were more prone to MGD than women (OR: 1.24, 95% CI 1.01–1.52, p = 0.034). The rate of MGD was between 21.2% and 29.5% in Africans and Caucasians, to 71.0% in Arabs, and 67.5% in Hispanics. Conclusion: MGD is a quite prevalent disorder with an estimated pooled prevalence of 35.8%. Men are more prone to MGD than women. There is a large variation between studies in terms of quality, sample size, age ranges, diagnostic criteria, and ethnicity.
Journal of Optometry, 2020
Purpose: To investigate vestibulo ocular reflex (VOR) in MS patients without any history of optic... more Purpose: To investigate vestibulo ocular reflex (VOR) in MS patients without any history of optic neuritis. Methods: 26 MS patients without any previous history of optic neuritis and 13 age-matched control subjects were included in this study. Their age ranged from 22 to 50 years old. We evaluated monocular visual evoked potential (VEP), monocular and binocular best corrected static and dynamic visual acuity, near and distance phoria and VOR gain. Results: Mean spherical equivalent (SE) was ---0.40 ± 0.93 D and ---0.04 ± 0.14 D for study and control group, respectively (P = 0.060). There was a significant difference in dynamic visual acuity (DVA) between two groups (P = 0.029). VOR gain was not significantly different in both groups through vHIT measurements (P = 0.338). Duration of MS had a mean of 78.38 ± 75.94 months (ranged from 6 to 336 months). We found no significant correlation between disease duration and VOR (Rho 0.277, P = 0.171) or DVA (Rho 0.782, P = 0.057). Conclusion: Our study showed that although vHIT results decreased in MS patients, there was no significant differences between two groups.
Journal of Ophthalmic and Vision Research, 2017
Purpose: This study aimed to compare pattern visual evoked potential (PVEP) components in dyslexi... more Purpose: This study aimed to compare pattern visual evoked potential (PVEP) components in dyslexic and normal children. Methods: This cross-sectional analytic study recruited 72 children, including 36 dyslexic and 36 normal participants aged 8-12 years. Visual examinations included measurement of distance visual acuity, refraction, and PVEP components of amplitudes and latencies with two different check sizes of 15 and 60 minutes (min) of arc at two contrast levels of 25% and 100%. Results: Our results demonstrated significant differences between dyslexic and normal children in terms of P100 latency and amplitude of PVEP at 25% contrast, with check sizes of 15 and 60 min of arc. However, there were no significant differences between the two groups regarding P100 latency and amplitude at 100% contrast with check sizes of both 15 and 60 min of arc. Conclusion: Dyslexic participants showed reduced amplitude and prolonged latency in most PVEP components at low-contrast levels. These findings may support the magnocellular deficit hypothesis in dyslexic participants, even though the parvocellular pathway remains intact.
Journal of Optometry, 2019
Purpose: Visual evoked potentials (VEPs) provide important diagnostic information related to the ... more Purpose: Visual evoked potentials (VEPs) provide important diagnostic information related to the functional integrity of the visual pathways. The aim of this study was to establish normative values of different components of pattern reversal VEPs on Iranian normal adult subjects. Methods: Monocular and binocular pattern reversal VEPs were recorded on 59 healthy participants (22.55 ± 3.79 years old) using the Roland RETI system for two check sizes of 15 and 60 min of arc. The measured VEP components were the latencies of N75, P100, N135 and amplitude of N75---P100. Results: Repeated measures ANOVA showed that viewing eye condition has a significant impact on the amplitude of N75---P100 (P < 0.001, F = 13.89). Also, the effect of check size on the latencies of N75, P100, N135, amplitude of N75---P100 (P ≤ 0.010), as well as the intraocular difference of P100 latency and amplitude N75---P100 (P = 0.007) was significant. More specifically, the amplitude of N75---P100 in both check sizes significantly differed between gender groups (P < 0.023). Conclusion: According to the results of this study, VEPs components are affected by the stimulus size, monocular and binocular recording conditions and gender. Therefore, it is necessary to determine the normative values of VEPs in each population, so that the results could be used in clinical studies.
Function and Disability Journal, 2018
Background & Objectives: To assess the effect of using tablets and smartphones on visual acuity a... more Background & Objectives: To assess the effect of using tablets and smartphones on visual acuity and vision-related performance in a population of visually impaired children. Methods: 24 children between the ages 4 to 13 years with visual acuity between 20/80 (0.6 Log Mar) to light perception participated in this study. The case group comprised children who scheduled to work with a tablet or smartphone for 2 hours a day for 6 months. The control group received nothing. Near and far vision as well as refraction were measured. Children of the two groups were asked to paint and the duration of painting was recorded. A questionnaire was designed to assess the quality of life the of children. All measurements were repeated 6 months later in both groups. There was no significant difference in vision between the two groups before using a tablet. Parents were also asked to explain any changes that occured in the behaviors of their children. Results: Distant vision in the tablet group was significantly different from the control group (P=0.04) which indicates improvement in visual acuity of the case group with about 0.20 Log Mar compared to the control group. There was 0.20 log Mar better vision in the tablet group in comparison with the control group (P=0.04). Results from the questionnaire showed that in the tablet group, the score was about 14.04 units better than the control group. The time consumption for painting was the same in both groups after 6 months. There was no significant difference in near acuity and refractive errors. Interviews with parents showed improvement in the tablet group in the area of navigation, mobility as well as objects' recognition. Parents stated that their child performed better in the environment. They had less accidents with objects and individuals. They were more comfortable in walking and using stairs. Conclusion: using tablets and smart phones by visually impaired children can improve distant vision and increase their functionality in performing daily life activities.
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Papers by javad heravian shandiz