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Abstract Purpose Our objective was to compare the serum Adropin levels between patients with wet-type Age-Related Macular Degeneration (AMD) and otherwise healthy individuals. Method The study included 45 patients with wet-type AMD and 45 individuals without age-related macular degeneration. Patients with co-morbidities such as diabetes, hypertension, autoimmune diseases, and a previous history of visual impairment; were excluded. FBS, Hemoglobin A1C (HbA1C), lipid profile, and serum Adropin level were checked. Results The mean serum Adropin level of patients with wet-type AMD was significantly lower than the control group (P-value

Abstract Background Age-related Macular Degeneration (AMD) is a complex eye disease, which is genetically associated with different susceptibility loci. We planned to investigate the possible association of Complement Factor B (CFB) rs4151667 (L9H) variants and their possible interaction with Complement Factor H (CFH) Y402H and Complement factor 3 (C3) rs2230199 (R102G) in AMD. Methods This case-control association study included 216 advanced type AMD patients and 191 healthy individuals for evaluation. Extracted-DNA samples were genotyped for the polymorphic regions of CFB rs4151667 (L9H), CFH Y402H and C3 rs2230199 (R102G). Results The distribution of CFB rs4151667 (L9H) genotypes was not significantly different in the AMD patients compared to that of controls (P = 0.18). The AT genotype frequencies for CFB was non significantly lower in AMD group (6.5% vs. 13.1%, AOR = 0.49, CI = 0.23–1.04, P = 0.064(. The A allele of CFB rs4151667 (L9H) was found to be non-significantly lower in AMD patients. CFB rs4151667 (L9H) had no protective interactional effect against CFH (Y402H) and C3 (R102G) risk variants. Conclusions This study showed that the protective role of CFB rs4151667 (L9H) in AMD is not significant and it has no significant protective interactional effect against CFH (Y402H) and C3 (R102G) risk variants.

Diabetic retinopathy is a medical condition of the damaged retina that is caused by diabetes and lack of proper monitoring and treatment, which usually leads to blindness. However, diabetic retinopathy monitoring requires an expert ophthalmologist. Recently, automatic monitoring models with acceptable efficiency are suggested as an alternative for expert ophthalmologists. In this paper, a new diabetic retinopathy monitoring model is proposed by using the Contrast Limited Adaptive Histogram Equalization method to improve the image quality and equalize intensities uniformly as the pre-processing step. Then, EfficientNet-B5 architecture is used for the classification step. The efficiency of this network is in uniformly scaling all dimensions of the network. The final model is trained once on a mixture of two datasets, Messidor-2 and IDRiD, and evaluated on the Messidor dataset. The area under the curve (AUC) is enhanced from 0.936, which is the highest value in all recent works, to 0.945. Also, once again, to further evaluate the performance of the model, it is trained on a mixture of two datasets, Messidor-2 and Messidor, and evaluated on the IDRiD dataset. In this case, the AUC is enhanced from 0.796, which is the highest value in all recent works, to 0.932. In comparison to other studies, our proposed model improves the AUC.

Background & objectives: Age-related macular degeneration (AMD) is a disease affecting the central vision and causing irreversible blindness in aging patients. AMD is a complex disease caused by the actions and interactions of multiple genes and environmental factors. Genomic region at chromosome 10q26 may have a bigger role in susceptibility to AMD. Age-related maculopathy susceptibility 2 (LOC387715/age-related maculopathy susceptibility 2(ARMS2)) gene at 10q26 is associated with the risk of AMD. Here we studied (A69S) rs10490924 polymorphism of LOC387715 gene in AMD patients from East Azerbaijan province of Iran. Methods: In this case-control study, the association of G>T in LOC387715/ARMS2 (A69S) rs10490924 polymorphism was investigated in 63 patients suffering from AMD and 150 healthy age, sex and ethnicity matched unrelated people as control group from northwest of Iran by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: Statistical analysis showed high frequency of TT genotype in AMD patients (34.92%) compared to those of control group (6.67%), (p value=0.000 OR=11.9). The frequency of heterozygotes (GT) was 32.67% in control group and 38.1% in the case group (p=0.422). The frequency of homozygotes (GG) was 60.66% in control group and 26.98% in the case group (p=0.000). Genotype analysis of LOC387715 like other studies in Chinese, Japan and a population in Iran revealed significant association in distribution between patients and controls. Conclusion: The data suggest that individuals from East Azerbaijan carrying TT genotype in LOC387715 have 11.9 times more risk of developing AMD compared to those carrying non-TT genotypes.

Introduction: Diabetic retinopathy (DR) is the most frequent microvascular complication of diabetes and can lead to several retinal abnormalities including microaneurysms, exudates, dot and blot hemorrhages, and cotton wool spots. Automated early detection of these abnormalities could limit the severity of the disease and assist ophthalmologists in investigating and treating the disease more efficiently. Segmentation of retinal image features provides the basis for automated assessment. In this study, exudates lesion on retinopathy retinal images was segmented by different image processing techniques. The objective of this study is detection of the exudates regions on retinal images of retinopathy patients by different image processing techniques. Methods: A total of 30 color images from retinopathy patients were selected for this study. The images were taken by Topcon TRC-50 IX mydriatic camera and saves with TIFF format with a resolution of 500 × 752 pixels. The morphological function was applied on intensity components of hue saturation intensity (HSI) space. To detect the exudates regions, thresholding was performed on all images and the exudates region was segmented. To optimize the detection efficiency, the binary morphological functions were applied. Finally, the exudates regions were quantified and evaluated for further statistical purposes. Results: The average of sensitivity of 76%, specificity of 98%, and accuracy of 97% was obtained. Conclusion: The results showed that our approach can identify the exudate regions in retinopathy images.

Introduction: Age-related macular degeneration (AMD) has become a catastrophic health problem throughout the world because of the aging population. Destruction of the macular architecture in the wet type form is a major problem that results from AMD and is irreversible. Working on preventive measures is, therefore, of critical importance. Because pentraxins (PTX) become elevated in the body in stressful, oxidized conditions, this study examines the role they play in AMD. The similarity between the pathophysiology of atherosclerosis and AMD and the role of PTX3 in atheromas were also factors that support conducting this study. Methods: This case-control study used 40 eyes that were at different stages of wet type AMD. The eyes were from patients who were over the age of 50 and had not had intraocular surgery or choroidal neovascularization (CNV) due to non-AMD causes. The control group included 49 eyes with normal macula. These study groups were matched according to age and gender, and the serum levels of PTX3 were analyzed. Results: The mean ages of the patients were 70.7 ± 9.0 and 69.6 ± 7.4 years among the case group and the control group, respectively (P = 0.540) while the male to female ratios were 2.64 and 1.19, respectively (P = 0.091). The PTX3 (P = 0.002), high-sensitivity C-reactive protein (hs-CRP) (P = 0.008) and triglyceride (TGs) (P = 0.032) were significantly higher among the wet type AMD cases. Conclusion: PTX3 appears to be a component in the pathogenesis of AMD and, therefore, could be a target for possible pharmaceutical interventions to stop or reduce the progression of this ominous disease.

Purpose: To customize clinical practice guidelines (CPGs) for management of diabetic retinopathy (DR) in the Iranian population. Methods: Three DR CPGs (The Royal College of Ophthalmologists 2013, American Academy of Ophthalmology [Preferred Practice Pattern 2012], and Australian Diabetes Society 2008) were selected from the literature using the AGREE tool. Clinical questions were designed and summarized into four tables by the customization team. The components of the clinical questions along with pertinent recommendations extracted from the above-mentioned CPGs; details of the supporting articles and their levels of evidence; clinical recommendations considering clinical benefits, cost and side effects; and revised recommendations based on customization capability (applicability, acceptability, external validity) were recorded in 4 tables, respectively. Customized recommendations were sent to the faculty members of all universities across the country to score the recommendations from 1 to 9. Results: Agreed recommendations were accepted as the final recommendations while the non-agreed ones were approved after revision. Eventually, 29 customized recommendations under three major categories consisting of screening, diagnosis and treatment of DR were developed along with their sources and levels of evidence. Conclusion: This customized CPGs for management of DR can be used to standardize the referral pathway, diagnosis and treatment of patients with diabetic retinopathy.

Introduction: Retinal capillary nonperfusion (CNP) is one of the retinal vascular diseases in diabetic retinopathy (DR) patients. As there is no comprehensive detection technique to recognize CNP areas, we proposed a different method for computing detection of ischemic retina, non-perfused (NP) regions, in fundus fluorescein angiogram (FFA) images. Methods: Whilst major vessels appear as ridges, non-perfused areas are usually observed as ponds that are surrounded by healthy capillaries in FFA images. A new technique using homomorphic filtering to correct light illumination and detect the ponds surrounded in healthy capillaries on FFA images was designed and applied on DR fundus images. These images were acquired from the diabetic patients who had referred to the Nikookari hospital and were diagnosed for diabetic retinopathy during one year. Our strategy was screening the whole image with a fixed window size, which is small enough to enclose areas with identified topographic characteristics. To discard false nominees, we also performed a thresholding operation on the screen and marked images. To validate its performance we applied our detection algorithm on 41 FFA diabetic retinopathy fundus images in which the CNP areas were manually delineated by three clinical experts. Results: Lesions were found as smooth regions with very high uniformity, low entropy, and small intensity variations in FFA images. The results of automated detection method were compared with manually marked CNP areas so achieved sensitivity of 81%, specificity of 78%, and accuracy of 91%.The result was present as a Receiver operating character (ROC) curve, which has an area under the curve (AUC) of 0.796 with 95% confidence intervals. Conclusion: This technique introduced a new automated detection algorithm to recognize non-perfusion lesions on FFA. This has potential to assist detecting and managing of ischemic retina and may be incorporated into automated grading diabetic retinopathy structures.

Introduction: The oxidative stress has been proposed as an important case of exudative age-related macular degeneration (E-ARMD). The aim of the present study was to investigate homocysteine (Hcy), asymmetric dimethylarginine (ADMA) and oxidized low-density lipoprotein cholesterol (Ox-LDL-C) levels, the factors involved in oxidative stress, in the patients with E-ARMD. Methods: In a cross-sectional study, 45 patients with E-ARMD were compared with 45 sex- and age-matched healthy controls. The levels of biochemical factors, Hcy, ADMA, and of Ox-LDL were estimated by standard methods in both study groups. Results: The levels of Hcy (15.4 ± 7.2 vs. 10.7 ± 3.7 μM, P = 0.001), Ox-LDL (52.2 ± 13.8 vs. 37.8 ± 10.8 U/l, P = 0.001), and ADMA (0.84 ± 0.23 vs. 0.71 ± 0.26 μM, P = 0.012) were significantly higher in the patients with E-ARMD than those in the controls. In the patient group, there was a positive and significant correlation between serum Ox-LDL and Hcy concentrations (r = 0.719, P = 0.001), but no correlation was found between serum ADMA and Ox-LDL (r = 0.010, P = 0.900) and also between serum Hcy and ADMA levels (r = -0.070, P = 0.600). Conclusion: The high levels of Hcy as an oxidant agent and ADMA as an endogenous nitric oxide synthase inhibitor can lead to increase Ox-LDL levels, and they may have important roles in oxidative stress, which can be a trigger in E-ARMD.

Introduction & Objective: Age-related macular degeneration (AMD) is a disease affecting the central regions of the retina and choroid, which can lead to loss of central vision. Etiological research suggests that AMD is a complex disease, caused by the actions and interactions of multiple genes and environmental factors. Numerous studies have focused on the role of chemotactic cytokines, also known as chemokines. Certain chemokines, such as CCL2 appear to be crucial in development of retinal degeneration and choroidal neovascularization. To de-termine whether variants in the CCL2 gene are associated with age-related macular degenera-tion we studied C-2518T polymorphism of this gene in AMD patients from Northwest of Iran. Materials & Methods: In this case-control study, the association of C-2518T polymorphism in the promoter region of CCL2 gene was investigated in 60 patients suffering from AMD and 50 healthy age, sex and ethnicity matched unrelated people as control group. Both of the case and control groups were originated from Northwest of Iran. Genotypes of both groups were determined by polymerase chain reaction (PCR) and restriction fragment length polymor-phism (RFLP). Results: Statistical analysis shows high frequency of TT genotype and T allele in AMD pa-tients compared to those of control group though the observed difference was not statistically significant. Conclusion: Despite the existence of small differences between case and control groups statis-tical analysis of single nucleotide polymorphism (SNPs) in the CCL2 gene did not show a significant association between C-2518T polymorphism and age-related macular degenera-tion.

AIM:To evaluate the high sensitivity C-reactive protein (hsCRP), Fetuin-A and matrix γ-carboxyglutamate protein (MGP) as the main factors for vascular calcification and inflammation in serum of patients with advanced age-related macular degeneration (ARMD) in comparison to healthy controls.METHODS: The subjects were 40 patients with choroidal neovascularization (CNV) having a mean age of 70.9±9.1y and a matched group of 49 apparently healthy control subjects. The ARMD was diagnosed using a slit-lamp with superfield lens, fundus photography and fluorescein angiography. Measurement of hsCRP was done by nephelometry method. Levels of Fetuin-A and MGP were measured by enzyme-linked immunosorbent assay (ELISA) technique.RESULTS:hsCRP [0.45(0.07-2.63) mg/L vs 0.25(0.03-1.2) mg/L, P=0.02)] and Fetuin-A levels (50.27±5.04 vs 44.99±10.28 ng/mL, P=0.009) were higher in the patients than in the control groups. We could not find significant difference in MGP level between two groups (P=0.08). There was not a significant correlation between MGP with Fetuin-A and hsCRP among the patients (P=0.7, P=0.9 respectively). A significant negative correlation of hsCRP with Fetuin-A was observed in both case and control groups (P=0.004, r=-0.33 and P=0.001, r=-0.54, respectively).CONCLUSION: Although our study shows that serum hsCRP and Fetuin-A is increased in CNV patients as well as negatively correlated with both study groups, their direct role on pathogenesis of ARMD required future studies.

To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest coefficients of variation in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low coefficients of variation . The contrast limited adaptive histogram equalization contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as contrast limited adaptive histogram equalization, for fundus images presented good potentials in enhancing the vasculature segmentation.

Introduction: One approach for the promotion of medical education is to evaluate the university professors’ teaching performance. A commonly-used technique is the student-based evaluation. This study aimed at determining the effective factors in the student-based evaluation of the university teachers’ performance in clinical education. Methods:This is a descriptive cross-sectional survey performed on medical residents in Tabriz University of Medical Sciences in June 2009. Data was collected by a questionnaire containing 44 items arranged in two sections. The respondents evaluated the statements on a five level Likert scale. The collected data were analyzed by SPSS-16. Results: In the clinical education domain, 94.4% of residents evaluated "the education during operation" as the most important factor. Other important factors were "the explanation ability" (86%) in the teaching ability domain, the "professors' knowledge ability and expertise" (93.5%) in the knowledge and skill domain, and "non-judgmental and non-humiliating behavior" (79%) in the personal characteristics and comportment domain. From the residents’ viewpoint, the most important educational domain affecting the evaluation of the academic members were the clinical education domain (average 4.39%) and the professors' knowledge ability and expertise (average 4.29%). Conclusion: Considering the nature of residency, practical training is of great importance. This study indicated that residents also consider practical training factors influential in evaluating their professors’ performance. The study pinpointed clinical education, teaching ability, comportment and personal characteristics, and knowledge and skill domain as important domains in evaluating university professors.

Calcification and inflammation are among the important cases of exudative age-related macular degeneration (E-ARMD). The aim of the present study was to elucidate if there is any relationship between serum Osteoprotegerin (OPG), soluble receptor activator of nuclear factor-kappa B ligand (RANK-ligand) and E-ARMD. In a cross-sectional study, we compared 45 E-ARMD patients with 45 matched controls. Diagnosis was confirmed by fluorescein angiography. Serum samples were analyzed for OPG, RANK-ligand, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglyceride (TG). The levels of OPG and RANK-ligand were measured by ELISA methods. The mean age was 72.0±11.5 years in the E-ARMD group and 68.2±8.9 years in the control group (p=0.09). The level of serum OPG was 132.10±75.49 pg/ml in the E-ARMD group and 94.88±61.65 pg/ml in the control subjects. E-ARMD patients had significantly high levels of OPG (p=0.012), as well as significantly high levels of LDL-C and TC (p=0.001 and p=0.005, respectively). We could not find any significant difference in RANK-ligand, HDL-C, or TG between two study groups (p>0.05). To the best of our knowledge, this is the first study investigating the levels of OPG in E-ARMD patients. The present study showed that E-ARMD patients had high levels of serum OPG. It may act as a protective factor for E-ARMD or only as a secondary phenomenon of different processes of E-ARMD. Further prospective studies would be necessary for prognostic and predictive significance of OPG in patients affected by E-ARMD.