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To compare Modulation Transform Function (MTF) between standard monofocal spherical hydrophobic acrylic Alcon SA60AT (Bausch and Lomb) and hydrophilic acrylic Rayner Superflex (620H) (Rayner) intra-ocular lenses (IOLs). This cross-sectional study was conducted on 68 patients who underwent cataract surgery. The hydrophobic Alcon SA60AT IOL was implanted in 39, and the hydrophilic Rayner Superflex (620H) was implanted in 29 eyes. The OPD Scan III (Nidek) was used to assess MTF in normal pupils under mesopic light conditions 1 and 3 months after the surgery. t-test showed no significant difference in mean MTF between the two IOLs in the 2 follow-ups (P=0.788). The results of repeated measure ANOVA for each type of IOL indicated that MTF increased significantly in the hydrophilic group versus the hydrophobic group in the 3rd month (P=0.033). Moreover, the results of repeated measure ANOVA showed that MTF was affected by the type of IOL and refractive error in the 3rd month (P=0.029, P=0.025). It seems that the material of IOL and post-surgical residual refractive error can affect the visual acuity of pseudophakic patients. Although the hydrophilic IOL provided a better MTF three months after the surgery, studies with longer follow-ups are required to confirm the results.

Purpose The aim of the present study was to investigate the change rate of astigmatism and axial, myopia, and hypermetropia in trabeculectomy and shunt surgery. Patients and methods In this comparative study, two groups of 16 patients with an average age of 52.4±8.9 and 94.6±6.7 respectively underwent trabeculectomy and shunt surgery. The changes of reactive error were compared before the surgery and 1 week, 1 month, and 3 months after the surgery. Data from the two groups were analyzed via Friedman and Mann-Whitney tests. Results Average of intraocular pressure (IOP) before, and 1 week, 1 month, and 3 months after trabeculectomy is 31.31±7.6, 9.8±2.8, 10.5±1.29, 10.9±1.26 (P 0.05). Percent WRT astigmatism in trabeculectomy is 37.5, 100, 37.5, 31.25 and in shunt it is 43.75, 50, 50, 56.25 and average of spherical equivalence (SE) in trabeculectomy is -0.31±1.49, 1.43±1.94, 0.27±1.74, 0.04±1.46 (P 0.05). Conclusion The surgeries induced hypermetropia and reduction with the passing of time but astigmatism amount and percent of with-the-rule astigmatism in trabeculectomy were more than in shunt surgery.

Purpose. This study was performed to determine achromatic contrast sensitivity and color vision in lead and zinc mine workers. Methods. A total of 230 male workers, who had been working in mine and had been in contact with minerals for at least 1 year, were considered as the case group, and the age of 90 years matched men who have not been in contact with minerals, being regarded as the control group. Contrast sensitivity was assessed using the Freiburg test at three frequencies of 1, 5 and 15 cycles of degree and under low mesopic light condition by two gratings and Landolt C stimuli. Color vision was assessed using the Farnsworth D-15 test under high mesopic light condition. Both tests were carried out monocularly. Data were analyzed using version 22 SPSS software. Results. There was a significant difference between studied groups with Landolt C stimulus in all three frequencies 1, 5 and 15 cycles per degree (p=0.009, p=0.016 and p=0.003). With Grating stimulus, there was a significant difference between the two groups in frequencies of 1 and 15 cycles per degree but at frequency of 5 cycles per degree, there was a border difference (p

To evaluate the accuracy of different corneal parameters in detecting keratoconus using a dual Scheimpflug/Placido system (Sirius, CSO, Italy).Sixty-eight eyes of 68 keratoconus patients and 77 eyes of 77 normal subjects were prospectively assessed in a diagnostic test study. The mean differences of the corneal parameters were compared using the independent t-test. The accuracy of curvature, elevation, pachymetry, and aberrometry indices, aqueous depth, and corneal volume in 10 mm was evaluated using the area under the curve (AUC), and the DeLong method was used for the comparison of AUCs. Multiple tests in a parallel manner and multiple logistic regression analysis were applied to determine the best predictor indices.All indices except aqueous depth and corneal volume were significantly different between the two groups (P 0.001). Back keratoconus vertex (KVb) and front Baiocchi-Calossi-Versaci index (BCVf) had the highest sensitivity (for both 98.53%) followed by front symmetry index (SIf) (96.12%) and thinnest point of the cornea (88.24%) in elevation, aberrometry, curvature, and pachymetry parameters, respectively. The highest diagnostic ability was observed in KVb (AUC 0.993) and BCVf index (AUC 0.992) (DeLong 0.05). Multiple test analysis showed a combination of indices with the highest accuracy that was similar to the performance of each one individually, and keratoconus was diagnosed correctly in 98.5% of the cases (RThe parameters extracted from Sirius can differentiate keratoconus from normal corneas with high accuracy without the need for complex computational algorithms. Elevation-based and combined aberrometry indices had the highest diagnostic power.

Purpose To evaluate the influence of colored light stimulus on simple visual reaction times. Methods Simple visual reaction times of colored light stimuli were measured in 100 young Iranian females with the mean age of 23.02±3.45 years (range from 18 to 30 years) in response to the four visual stimuli (red, green, yellow and blue light) by using Speed Anticipation and Reaction Tester (SART) software. Results The analysis of variance (ANOVA) test to compare visual reaction time showed a significant difference (P

Purpose To compare contrast sensitivity (CS) in multi-transfused β-thalassemia patients who received deferoxamine with those who received Osveral. Methods In this cross sectional study a total of 60 β-thalassemia patients (30 used deferoxamine and 30 used deferasirox) were regarded as case group and 30 age and sex matched healthy subjects were selected as control group. All subjects had a set of examinations including refraction, visual acuity, Biomicroscopy, ophthalmoscopy and CS. Contrast threshold was assessed with the use of Freiberg visual acuity and contrast test under the mesopic light condition for three frequencies; 1, 5, 15 cpd. All data analysis was performed using SPSS, version 17. Results In visual acuity tests, thalassemic patients did not have any problem. Contrast threshold was higher in thalassemic patients who infuse deferoxamine (1.87 ± 0.63, 1.46 ± 0.81, and 2.96 ± 1.68 in 1, 5, and 15 cpd, respectively) than that of those who intake deferasirox (1.74 ± 0.80 (P = 0.743), 0.99 ± 0.74 (P = 0.047), and 2.42 ± 1.36 (P = 0.321) for 1, 5, and 15 cpd, respectively), and also than healthy patients (1.33 ± 0.58 (P = 0.009), 0.95 ± 0.68 (P = 0.022), and 2.24 ± 1.23 (P = 0.135) for 1, 5, and 15 cpd, respectively). Comparing those who used deferasirox with healthy subjects, contrast threshold was higher in deferasirox group at all special frequencies (P > 0.05). No significant relationship was observed between CS values and duration of transfusion, serum ferritin concentration and dose of chelation therapy (P > 0.05). Conclusions CS tests can detect visual disturbance in thalassemic patients before the impairment of visual acuity. It is suggested that CS tests be included in their regular eye examination.

Objective: We conducted the present work to evaluate cornea biomechanics, using Corvis-‎ST device parameters amongst patients with diabetes mellitus‎.Methods: In this cross-sectional study, 62 type II diabetic patients and 28 non-diabetic individuals were recruited. Following slit-lamp examination, the participants were further assessed and compared with Corvis-ST device (OCULUS Germany) in order to evaluate the cornea biomechanical response.‎Result: The Applanation 2 Velocity variable was significantly different between ‎the diabetic and non-diabetic patients (-0.3±0.04, respectively) (P value=0.02). ‎Conclusion: This study revealed an increased corneal biomechanical strength amongst diabetic patients.

To determine the distribution of corneal-compensated intraocular pressure (IOPcc), Goldmann-correlated intraocular pressure (IOPg) and their associated factors in a geriatric population.The present cross-sectional study was performed in individuals above 60 years of age in Tehran, the capital of Iran. The sampling was performed using multi-stage random cluster sampling method. All participants underwent preliminary ocular examinations, and then imaging by Pentacam HR and IOL master 500. Measurement of IOPg, IOPcc, and corneal biomechanical indices including corneal hysteresis (CH) and corneal resistant factor (CRF) was performed in a random sub-sample using ocular response analyzer (ORA).The mean IOPg and IOPcc were 16.76 ± 4.71 mmHg and 19.05 ± 4.67 mmHg, respectively. There were no statistically significant differences in both IOPg (p = 0.891) and IOPcc (p = 0.248) between males and females. Based on the multiple linear regression models, both IOPg and IOPcc showed a statistically significant direct relationship with CRF (P 0.001) and a significant inverse relationship with CH (P 0.001 for IOPg and IOPcc), anterior chamber angle (ACA) (p = 0.006 for IOPg and p = 0.017 for IOPcc), and spherical equivalent refractive error (p = 0.032 for IOPg and p = 0.046 for IOPcc).Mean IOPg and IOPcc in the present study were higher compared to most previous studies. Corneal biomechanical indices including CH and CRF, refractive error and anterior chamber angle were independent associated factors of IOPg and IOPcc in the present study. There was no significant relationship between ORA-derived IOP values and CCT.

Purpose The aim of the present study was to investigate the change rate of astigmatism and axial, myopia, and hypermetropia in trabeculectomy and shunt surgery. Patients and Methods In this comparative study, two groups of 16 patients with an average age of 52.4±8.9 and 94.6±6.7 respectively underwent trabeculectomy and shunt surgery. The changes of reactive error were compared before the surgery and 1 week, 1 month, and 3 months after the surgery. Data from the two groups were analyzed via Friedman and Mann–Whitney tests. Results Average of intraocular pressure (IOP) before, and 1 week, 1 month, and 3 months after trabeculectomy is 31.31±7.6, 9.8±2.8, 10.5±1.29, 10.9±1.26 (P0.05). Percent WRT astigmatism in trabeculectomy is 37.5, 100, 37.5, 31.25 and in shunt it is 43.75, 50, 50, 56.25 and average of spherical equivalence (SE) in trabeculectomy is −0.31±1.49, 1.43±1.94, 0.27±1.74, 0.04±1.46 (P0.05). Conclusion The surgeries induced hypermetropia and reduction with the passing of time but astigmatism amount and percent of with-the-rule astigmatism in trabeculectomy were more than in shunt surgery.

Beta thalassemia (β-thalassemia) is a hereditary disease caused by defective globin synthesis and can be classified into three categories of minor (β-TMi), intermedia (β-TI), and major (β-TM) thalassemia. The aim of our study is to investigate the effects of β-thalassemia and its treatment methods on different parts of the eye and how early-diagnostic methods of ocular complications in this disorder would prevent further ocular complications in these patients by immediate treatment and diet change. We developed a search strategy using a combination of the words Beta thalassemia, Ocular abnormalities, Iron overload, chelation therapy to identify all articles from PubMed, Web of Science, Scopus, and Google Scholar up to December 2018. To find more articles and to ensure that databases were thoroughly searched, the reference lists of selected articles were also reviewed. Complications such as retinopathy, crystalline lens opacification, color vision deficiency, nyctalopia, depressed visual field, reduced visual acuity, reduced contrast sensitivity, amplitude reduction in a-wave and b-wave in Electroretinography (ERG), and decrease in the Arden ratio in Electrooculography (EOG) have all been reported in β-thalassemia patients undergoing chelation therapy. Ocular problems due to β-thalassemia may be a result of anemia, iron overload in the body tissue, side effects of iron chelators, and the complications of orbital bone marrow expansion.

Purpose: To review current non-surgical management methods of intermittent exotropia (IXT) which is one of the most common types of childhood-onset exotropia. Methods: A search strategy was developed using a combination of the words IXT, divergence excess, non-surgical management, observation, overcorrecting minus lens therapy, patch/occlusion therapy, orthoptics/binocular vision therapy, and prism therapy to identify all articles in four electronic databases (PubMed, Web of Science, Google Scholar, and Scopus). To find more articles and to ensure that the databases were thoroughly searched, the reference lists of the selected articles were also reviewed from inception to June 2018 with no restrictions and filters. Results: IXT is treated when binocular vision is impaired, or the patient is symptomatic. There are different surgical and non-surgical management strategies. Non-surgical treatment of IXT includes patch therapy, prism therapy, orthoptic sessions, and overcorrecting minus lens therapy. The objective of these treatments is to reduce the symptoms and the frequency of manifest deviation by decreasing the angle of deviation or enhancing the ability to control it. Conclusions: Evidence of the efficacy of non-surgical management options for IXT is not compelling. More comprehensive randomized controlled trial studies are required to evaluate the effectiveness of these procedures and detect the most effective strategy.

To evaluate discrete wavelet transform coefficients and identify descriptors of pattern electroretinogram (PERG) waveforms in order to determine PERG characteristics for optimizing the diagnosis of early primary open-angle glaucoma (POAG). Pattern electroretinogram was performed in 30 normal eyes and 30 eyes with primary open-angle glaucoma according to the ISCEV protocol. The check size was 0.8° and 16°, and the color was black/white in both groups. The results were analyzed in time domain (TD) and discrete wavelet transform (DWT) using the MATLAB software. The mean value, standard deviation, and relative energy of level 6 and 7 detail coefficients (d6, d7) and level 7 approximation coefficients (a7) of Daubechies 4 (db4), Daubechies 8 (db8), Symlet 5 (sym5), Symlet 7 (sym7), and Coiflet 5 (coif5) wavelets were calculated. In all the mentioned wavelets, DWT descriptors were extracted. Signals were reconstructed by inverse DWT. All data obtained by TD and DWT analyses were compared between the two groups. In both check sizes, a significant attenuation of N95 amplitude was seen in the patient group. The relative energy of a7 of db8 increased significantly in the POAG group in the 0.8° check size. In larger check stimuli, the relative energy of d7 of coif5 decreased significantly and the standard deviation of d7 of sym7 increased markedly in glaucomatous patients (P

Purpose: The present study aims at investigating and comparing the vision-related quality of life of myopic persons who wear spectacles or contact lenses with those who have undergone refractive surgery. It also compares the vision-related quality of life of these two groups with that of emmetropes. Method: In this study, the questionnaire of evaluation instrument of refractive error in quality of life (NEI/RQL-42) was used to compare the quality of life between 154 myopic patients with spectacles and contact lenses, and 32 patients who have undergone refractive surgery. The two groups were also compared with 54 emmetropes. The questionnaire included 13 different subgroups (score 0–100) related to vision. Data was analyzed using SPSS software. Results: The overall score of quality of life in emmetropes (95.11 ± 4.23) was more than that in persons who had undergone refractive surgery (86.98 ± 4.73), and it was the least in the group wearing spectacles or contact lenses (78.30 ± 9.21), (P < 0/001). Furthermore, except for a glare variable, the studied groups indicated a statistically significant difference in all the thirteen subgroups of vision-related quality of life. Conclusion: Quality of life for people with myopia who had the refractive surgery was better than people with myopia who wore spectacles or contact lenses. Although quality of life in people with myopia who had the refractive surgery was less than emmetropia, it seems that refractive surgery improves quality of life of myopic patients.

To compare the refractive and visual outcomes and higher order aberrations in patients with low to moderate myopia who underwent customized photorefractive keratectomy (PRK) or femtosecond laser in situ keratomileusis (Femto-LASIK) this research performed. This study includes data of 120 consecutive eyes of 60 patients with myopia between -3.00 D and -7.00 D with or without astigmatism in two surgery groups: PRK and Femto-LASIK. Refractive, visual, and aberration outcomes of the two methods of surgery were compared after 6 months of follow-up. After six months of follow-up, sphere and cylinder were found significantly decreased and there was no statistically significant difference between the two groups. The mean of uncorrected distance visual acuity in LogMar format for the PRK and Femto-LASIK groups was -0.03±0.07 and -0.01±0.08, respectively, which was not significantly different between the two groups. Higher orders and spherical aberrations increased in both groups significantly, while total aberrations decreased in both groups. After surgery, no differences were observed between the two groups in the amount of aberrations. In conclusion, Both PRK and Femto-LASIK are effective and safe in correcting myopia. In this study PRK induced more spherical and higher order aberrations than Femto-LASIK.

Purpose To determine the distribution of ocular biometric parameters and their correlation with age and gender during the eye growth. Methods In a cross-sectional study, a multi-stage stratified cluster sampling was used to sample the study population from Dezful schools, a city in the southwest of Iran. Participants were selected from the all school grades and both genders. Examinations were performed after obtaining consent from the subjects's parent. LENSTAR/BioGraph (WaveLight AG, Erlangen, Germany) was used for ocular biometry. Results Of 864 selected subjects, 683 participated in the study (response rate:79.1%); 377 participants (55.2%) were males. Mean age of the subjects was 12±3.4 years (range: 6.0-18 years). Mean and 95% confidence interval(CI) of axial length (AL),anterior chamber depth (ACD), lens thickness (LT),central corneal thickness (CCT),corneal diameter (CD), and pupilary diameter(PD) were 23.13 mm (22.93-23.33), 3.01 mm (2.96-3.06), 3.58 mm (3.55-3.61), 549.33 mic (546.59-552.07), 12.34 mm (12.31-12.38), and 4.97 (4.91-5.03), respectively. Ocular biometric parameters were normally distributed. Distribution of LT and CD were leptokurtic and the distribution of the PD was platykurtic. The mean of AL, ACD, CD and CR were significantly higher in boys and the mean of LT was significantly higher in girls. Axial length and ACD increased and the LT decreased significantly with age. Axial length and CR had the highest correlation (r=0.669) and ACD had the strongest correlation with the Conclusion The results of this study indicated that AL and ACD were intermediate and shorter respectively. Corneal diameter was bigger in comparison with the other studies. The majority of the changes were observed in AL and LT.

Many studies show that congenital defects in infants conceived by assisted reproductive techniques (ART) are more than infants of normal conception (NC). The aim of this study is to determine the frequency of congenital anomalies in ART infants from Royan Institute and to compare congenital anomalies between two ART techniques. In a cross-sectional descriptive study, 400 ART infants from Royan Institute who resided in Tehran were selected by non-random, consecutive sampling. Infants were examined twice (until 9 months of age) by a pediatrician. Infants' congenital anomalies were described by each body system or organ and type of ART. Data were analyzed by SPSS version 16 and Fisher's exact test.The frequency of different organ involvement in the two examinations were: 40 (10%) skin, 25 (6.2%) urogenital system, 21 (5.2%) gastrointestinal tract, 13 (3.2%) visual, and 8 (2%) cardiovascular system. Major congenital defects in infants conceived by in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) were hypospadiasis, inguinal hernia, patent ductus arteriosus plus ventricular septal defect (PDA + VSD), developmental dysplasia of the hip, lacrimal duct stenosis during the first year of life, hydronephrosis and urinary reflux over grade III, undescending testis, ureteropelvic junction stenosis, and torticoli.Two-thirds of ART infants had no defects. A total of 7% of IVF and ICSI infants had one of the major abovementioned congenital anomalies. This rate was higher than NC infants (2%-3%). There was no difference between the ICSI and IVF group.