dr. hassan hashemi

Carpal tunnel syndrome (CTS) is a common peripheral nerve entrapment disorder that is diagnosed using clinical signs and symptoms and confirmed via nerve conduction studies (NCSs). While NCS is a semi-invasive procedure, magnetic resonance imaging (MRI) is a non-invasive diagnostic tool that detects macroscopic nerve abnormalities and evaluates a patient's surgical or medication treatment options. This study assessed magnetic resonance neurography (MRN)’s diagnostic and grading value by comparing it to electrodiagnostic studies in patients with CTS and healthy individuals. This was a cross-sectional study on 27 wrists with CTS and 27 healthy wrists. After history taking and physical examination, we employed an NCS to confirm and determine the severity of CTS, then MRN and diffusion tensor imaging (DTI) were used to calculate apparent diffusion coefficient (ADC), fractional anisotropy (FA), and cross-sectional area (CSA). 18 patients with CTS (27 median nerves) and 15 healthy controls (27 median nerves) were evaluated. The mean FA in the CTS group was significantly lower (0.38 ± 0.05 vs. 0.45 ± 0.06, P < 0.001). The mean CSA and ADC were higher in patients with CTS but not statistically significant. FA’s diagnostic cut-off was 0.42, with a sensitivity of 70.4% and a specificity of 63%. MRN with DTI can be an effective and non-invasive diagnostic technique for the detection of CTS. The FA measure demonstrated adequate sensitivity and specificity for differentiating patients with CTS from healthy individuals.

 Corneal abnormalities are one of the important reasons for visual impairment. There is little evidence of the prevalence of different types of corneal abnormalities. The aim of this study was to assess the prevalence of various corneal abnormalities and identify the key risk factors associated with these abnormalities in an elderly population residing in Tehran.

 The Tehran Geriatric Eye Study (TGES) was conducted as a cross-sectional study, utilizing a population-based approach and employing stratified cluster random sampling. The study focused on individuals aged 60 years and above residing in Tehran. An ophthalmologist performed a slit lamp examination to evaluate the eyelid, cornea, and crystalline lens.

 The prevalence of posterior embryotoxon (PE), punctate epithelial defect (PED), pigment on endothelium (POE), corneal dystrophy (CDys), corneal vascularization (CV), and corneal degeneration (CDeg) were estimated to be 0.08% (95% confidence interval [CI]: 0.02 to 0.40), 8.77% (95% CI: 6.64 to 11.51), 0.57% (95% CI: 0.33 to 0.98), 0.53% (95% CI: 0.33 to 0.82), 0.95% (95% CI: 0.60 to 1.52), and 44.87% (95% CI: 41.80 to 47.98), respectively. Overall, approximately 49.08% of the participants exhibited some form of corneal abnormality in at least one eye. The multiple logistic regression model revealed that increasing age was significantly associated with PED, CV, and CD. Furthermore, illiterate participants had a significantly higher prevalence of PE.

 The findings of this study indicate that approximately half of the elderly population aged 60 years and above in Tehran have at least one corneal abnormality, with corneal degeneration being the most prevalent. Age was identified as the primary determinant of corneal abnormalities.

To determine the distribution of macular thickness and macular volume in an elderly healthy population 60 years of age and above and their determinants.

The sampling was performed using a multistage stratified random cluster sampling method on the geriatric population 60 years of age and above in Tehran, Iran. All participants underwent optometric examinations, slit‑lamp examination, and optical biometry. Retinal imaging was performed by spectral‑domain optical coherence tomography.

The means ± standard deviation and 95% confidence interval of central macular thickness (CMT), average macular thickness (AMT), and macular volume were 221 ± 33 (218–223) μm, 267 ± 29 (265–269) μm, and 8.36 ± 0.44 (8.33–8.39) mm3, respectively. The CMT was significantly lower in females than males (β: −5.77; P = 0.002). The AMT was significantly lower in females than males (β = −10.32; P < 0.001) and was significantly directly related to intraocular pressure (β = 0.63; P = 0.038). The macular volume was significantly lower in females than males (β = −0.13; P < 0.001) and decreased with age (β = −0.01; P < 0.001). In addition, the macular volume had a significant inverse and direct relationship with axial length (β = −0.04; P = 0.011) and keratometry (β = 0.03; P < 0.001).

Macular thickness in the Iranian geriatric population was slightly less than the populations studied in other countries. The role of sex should also be taken into account in the interpretation of macular thickness findings.

  Promotion of Ophthalmic Education and practice is one of the main priorities for policy makers in ophthalmology. This study aimed to present experts solutions to accomplish an Ideal Status for Ophthalmic Fellowship Education in Iran over a 10- year horizon.

In this applied qualitative research, using purposive sampling, 11 key informants of Iran’s Ophthalmic Fellowship Education invited to participate in an expert panel on February2023. The data analyzed by thematic approach.

 in this article the identified solutions to achieve desired status for fellowship education in ophthalmology were presented in 14 main themes, and 44 subthemes.Based of consensus of experts, this study, proposed 14 applied solution including: Revising the ophthalmic fellowship curriculum to the highest quality, promoting accountability, promoting professionalism , constant interaction with clinical research sectors,  reform in national system of  fellowship’s admission, reform in fellowships  program evaluation  and accreditation system, decentralization of ophthalmic fellowship admission, Integration of some ophthalmic fellowship disciplines, cut unnecessary admissions and increase admissions in required  ophthalmic fields , foresight  in workforce planning ,  cost-effectiveness analysis  in fellowship programs development , ophthalmic services tariffs reform, Ophthalmologists retention policy reform , Investing and building technological infrastructures.

 The priority areas and applied solutions to actualize the ideal situation for ophthalmic fellowship education of the highest quality in response to community and health system demands are determined .The experts recommendations should be considered through revision of policies, standards and practical mechanisms by educational  planners to promote ophthalmic fellowship education in IRAN.

The present study sets out to investigate the effect of cyclopentolateinduced cycloplegia on distance and near deviation and the accommodative convergence/accommodation (AC/A) ratio.

This prospective study was performed on 30 subjects. The inclusion criteria included a lack of any active ocular pathology and systemic diseases, no history of ocular surgery, and nonuse of various medications. Refraction, near and distance deviation were measured for all subjects, and the same examinations were repeated after the administration of two drops of cyclopentolate 1% to both eyes.

The obtained data from 30 subjects, including 19 males, with a mean age of 22.53 ± 1.74 years were analyzed. The mean ± SD of near deviation in dry and cycloplegic conditions were – 6.9 ± 8.1 and +6.4 ± 9.1 prism diopters, respectively, which were statistically significant (P < 0.001). Distance deviation in cycloplegic conditions demonstrated an average difference of 0.8 prism diopters, compared to dry conditions (P < 0.001). AC/A ratios were 4.7 ± 2.5 and 9.7 ± 3.9 (Δ/D) in non-cycloplegic and cycloplegic conditions, respectively, which was a statistically significant difference (P < 0.001). The multiple regression indicated that among all under study variables, refraction (B coefficient: –2.4; P < 0.001) and near pre-cycloplegic deviation (B coefficient: 0.56; P < 0.001) were significantly associated with post-cycloplegic near deviation.

The results of this study indicated that cycloplegia causes a considerable esophoric shift in near deviation and a negligible esophoric shift in distance deviation. As a result, the AC/A ratio demonstrated a significant increase due to unequal changes in near and distance deviation.

To determine the long-term effects of night shift work on dry eye in hospital nurses.

Each participant was evaluated four times, including at the beginning of the day shift (8 am), at the end of the day shift (2 pm), at the beginning of the night shift (8 pm), and at the end of the night shift (8 am), using the tear break-up time (TBUT) test and ocular surface disease index (OSDI) questionnaire.

The results showed significant differences in the TBUT and OSDI between the end of the day shift (2 pm) (10.26, 16.61) and the end of the night shift (8 am) (6.89, 38.59) relative to each other and relative to the beginning of the day and night shifts. As for the correlation between TBUT and OSDI, a significant correlation was found at all measurement times (correlation coefficient: −0.478, −0.707, −0.556, and −0.365, respectively) (p < 0.05).

The results showed that the severity of dry eye increased after the night shift with variation over a 24-hr period. Moreover, a significant correlation was observed between TBUT and OSDI results at the beginning and at the end of the day and night shifts.

Development of Fellowship Education is constantly one of the strategies of medical education policy makers because of the key role of graduated fellowships in advanced health care. This study aimed to comprehensively analyzes the current status for Ophthalmic Fellowship Education in Iran.

In this applied qualitative foresight study, using purposive sampling, eleven experts and key informants of Iran’s Ophthalmic Fellowship Education, selected, and invited to participate in a panel of experts. A panel meeting for focused discussion was held on February2023. The data analyzed by thematic approach.

The identified strength points and challenges are presented in 23 main themes, and 65 subthemes. The seven main themes for strengths included, systematic management, successful policies in ophthalmology education, effectiveness of fellowship programs, increasing motivation for academic growth, faculty empowerment, improving access to advanced services, avoiding procedures with questionable indications.
Sixteen themes for challenges included: low educational quality in some centers, lack of community based education, weak professional ethics, low quality of research, lack of comprehensiveness, lack of futuristic approach in developing fellowships, lack of workforce planning, ineffective evaluation system , ineffective centralized admission system, unbalanced admission capacity, receiving fellowship degree to make extra income, performing ophthalmic procedures not related to their fellowship fields , refuse to operate high risk ophthalmic procedures, unattractive Tariffs, regional disparity of medical resources, shortage of advanced technological infrastructures.

Based on experts’ consensus, forward-looking planning is effective in order to maintain the achievements, solve the challenges and improve these courses in line with the desired perspective.

Intracranial chondroma and chondrosarcoma are very rare tumors that mainly originate from the base of the skull. Advanced neuroimaging studies, including magnetic resonance spectroscopy (MRS), play a pivotal role in both tumor diagnosis and presurgical planning.

We present two cases of intracranial cartilaginous tumors, including a chondroma and a chondrosarcoma, both of which presented with severe headaches. Due to inconclusive conventional MRI and MRS results, they were both primarily diagnosed as intra-axial brain tumors. However, pathological reports later confirmed the diagnosis of a chondroma and a chondrosarcoma.

Based on the present findings, the use of advanced neuroimaging techniques, such as MRS, may improve diagnostic accuracy. We believe that MRS can play a significant role in the surgical planning of similar cases. Also, reporting rare cases worldwide can contribute to the improvement of radiographic diagnosis.

To report the study protocol, methodology and latest enrollment data of a large epidemiological multi-central eye cohort named PERSIAN Eye Cohort Study (PECS), originating from the ongoing PERSIAN Cohort Study, to investigate the distribution of ophthalmic disorders in different regions and ethnicities of Iran, and determine their associations with various exposures of ophthalmic and non-ophthalmic nature.

A central committee designed the study and equipped six chosen centers (Khameneh, Some’e Sara, Hoveizeh, Yazd, Rafsanjan and Zahedan). A focal point in each center conducted the study under close supervision of the central committee.

This ongoing study was launched in 2014. Out of 65,580 eligible participants of the PERSIAN Cohort, 48,618 individuals aged 35-70 have been enrolled in the PECS (response rate: 74.13%) until June 2021. Slit lamp and fundus photography were performed for 28,702 (59.03%) and 27,437 (56.43%) individuals, respectively.

This large epidemiological multi-central eye cohort can improve our epidemiological knowledge of the prevalent ophthalmic disorders in different regions and ethnicities of Iran, and determine their associations with various exposures of ophthalmic and non-ophthalmic nature. This will be very useful for future planned nationwide and global interventions.

Leachate, a highly contaminated liquid, is produced by separating wastes and introducing moisture into the waste layers. Biological toxicity evaluation is a method that may be used to analyze the toxicity of leachate to organisms and plants. Sorghum bicolor was employed in this study to evaluate the acute toxicity of raw leachate and landfill leachate.

Leachate was collected from different locations within the refuse that was collected and mixed in a sampling container. The physiochemical characteristics of the leachate were analyzed in both raw leachate and landfill leachate. Germination rate, root weight, and root length were measured 24, 48, and 72 hours after planting for leachate dilutions of 25%, 50%, 75%, and 100%, respectively.

Raw leachate had greater concentrations of metals (Fe, Zn, Cu, Mn, Cr, Cd, and Pb), chemical oxygen demand (COD), total dissolved solids (TDS), total suspended solids (TSS), nitrate, ammonia, and phosphate, as well as a more acidic pH (< 6), as compared to landfill leachate. The results showed that landfill leachate had a lower potential for toxicity than raw leachate, with seed-germination rates of 0.1 and 0 in the presence of 75% landfill leachate after 48 and 72 hours, respectively, as opposed to 0.3 and 0.1 in the presence of raw leachate.

The findings show that raw leachate can include higher concentrations of metals and organic compounds, which can be one of the causes of Sorghum seed phytotoxicity. Waste leachate management is one of the most important pillars of environmental protection, and it should be taken into consideration by the right authorities.

To determine the prevalence of different types of ocular trauma and their relationship with some factors in the elderly population.

The present population‑based cross‑sectional study was conducted on the elderly population aged 60 years and above in Tehran, Iran, using multi‑stage stratified random cluster sampling in 2019. After selecting the samples and their participation in the study, demographic information and history of ocular trauma were obtained through an interview. Psychological evaluation was performed using the Goldberg’s 28‑question General Health Questionnaire. All study participants underwent optometric and ophthalmological examinations.

Three thousand three hundred and ten people participated in the study (response rate: 87.3%). Of these, 1912 individuals (57.8%) were female and the mean age of individuals was 68.25 ± 6.55 (from 60 to 97) years. 7.46% (95% confidence interval [CI]: 6.51–8.41) of the study participants reported a history of ocular trauma. Blunt and chemical traumas were the most and the least common types of ocular trauma, respectively (5.72% and 0.16%). 3.93% of cases visited an ophthalmologist for ocular trauma, 1.67% reported a history of hospitalization, and 1.47% underwent surgery. The prevalence of visual impairment in individuals with a history of ocular trauma was 12.53%. Visual impairment was more prevalent in people with a history of ocular trauma than those without a history of ocular trauma (P < 0.05). History of ocular trauma was only significantly related to low education level (odds ratio = 0.63, 95% CI = 0.40–0.99). Participants with a history of ocular trauma had more anxiety and higher mean psychological distress score than those without a history of ocular trauma (P = 0.035).

The development of preventive programs against the occurrence of ocular trauma can play an important role in reducing the psychological damage of affected patients while reducing visual disorders. These interventions should be especially considered in groups with a lower education level.

This study aims to evaluate the role of Shear Wave Elastography (SWE) in the differentiation of malignant from benign cervical lymph nodes and compare its accuracy with conventional ultrasound.  Seventy-one lymph nodes (malignant=52, benign=19) were investigated by both conventional sonography and SWE. Shear Wave Velocity (SWV) and color map were obtained for each lymph node before tissue sampling. R statistical software (x64, v3.6.1) was used for statistical analysis. Among all the conventional and elastography features, color map grading and shear wave velocity (SWV) had the most correlation with malignancy, even in normal-sized nodes. SWV was significantly correlated with the pathology (rpb=0.62, p<0.00). The best cutoff-value for SWV was 2.71 m/s (sensitivity: 82.7%, specificity:84.2%, AUC=0.92). The best predicting model by multivariate analysis was obtained by a combination of SWV and color map grading (sensitivity=92.3%, specificity=94.7%).  SWE is a valuable method for the differentiation of malignant from benign lymph nodes. It would help to find the proper lymph node for biopsy.

To determine the prevalence of visually significant uncorrected refractive error (URE) in Rafsanjan and investigate the related factors. URE is the leading cause of visual impairment (VI) which causes the second‑highest number of years lived with disability. The URE is a preventable health problem.

In this cross‑sectional study participants from Rafsanjan who were 35–70 years were enrolled between 2014 and 2020. Demographic and clinical characteristics data were gathered, and eye examination was performed. Visually significant URE was defined as present if habitual visual acuity was (HVA; visual acuity with present optical correction) >0.3 logMAR in the best eye and the visual acuity of that eye showed >0.2 logMAR improvement after the best correction. Logistic regression was used to determine the association between predicting variables (age, sex, wealth, education, employment, diabetes, cataract, and refractive error characteristics) and outcome (URE).

Among the 6991 participants of Rafsanjan subcohort of the Persian Eye Cohort, 311 (4.4%) had a visually significant URE. Diabetes was significantly more prevalent in the participants with visually significant URE, at 18.7% versus 13.1% in patients without significant URE (P = 0.004). In the final model, each year of increase in age was associated with 3% higher URE (95% confidence interval [CI]: 1.01–1.05). In comparison to low hyperopia, participants with low myopia had 5.17 times more odds of visually significant URE (95% CI: 3.38–7.93). However, antimetropia decreased the risk of visually significant URE (95% CI: 0.02–0.37).

Policymakers should pay special attention to elderly patients with myopia to effectively reduce the prevalence of visually significant URE.

Assessment of the pattern visual evoked potential (PVEP) responses in different areas of visual fields in individuals with normal vision.

This study was conducted on 80 eyes of normal subjects aged 18–35 years. All participants underwent refraction and visual acuity examination. Visual evoked potential (VEP) responses were recorded in different areas of field. The repeated measure test was used to compare the P100 latency and amplitude of PVEP among different areas.

The repeated measures analysis of variance showed a statistically significant difference among different areas in terms of amplitude and latency of P100 (P = 0.002 and P < 0.001, respectively). According to the results, the highest and lowest amplitude of P100 was observed in inferior-nasal and superior areas, respectively. The highest and lowest latency of P100 was related to the temporal and inferior-nasal areas, respectively.

This study partially revealed the details of local PVEP distribution in the visual field and there was a significant difference in the amplitude and latency of PVEP wave in different areas of the visual field.

To determine the distribution of corneal biomechanical parameters in an elderly population.

This cross‑sectional study was conducted in subjects above 60 years living in Tehran. The participants were selected using multi‑stage cluster sampling. Corneal biomechanical parameters were measured in a randomly selected subsample of this population using the Reichert Ocular Response Analyzer (Reichert Ophthalmic Instruments, Inc., Buffalo, NY, USA).

Of 470 subjects, the data of 420 participants aged over 60 years were analyzed (mean age: 69.3 ± 6.5 years and range: 61–88 years), 363 (86.4%) of whom were male. The mean and standard deviation of corneal hysteresis (CH) and corneal resistance factor (CRF) were 8.37 ± 1.55 mmHg (95% confidence interval [CI]: 8.02–8.72) and 9.06 ± 1.70 mmHg (95% CI: 8.69–9.44), respectively. The mean CH was 8.27 ± 1.54 mmHg in men and 9.25 ± 1.28 mmHg in women, and the mean CRF was 9.00 ± 1.71 mmHg in men and 9.63 ± 1.37 mmHg in women. According to the results of multiple linear logistic regression analysis, CH had a significant association with younger age (β = −0.05, P = 0.032), female sex (β = 1.83, P < 0.001), reduced maximum keratometry (β = −0.22, P = 0.06), and increased anterior chamber volume (β = 0.01, P = 0.007). CRF had a significant correlation with a younger age (β = −0.06, P = 0.02), female sex (β = 1.01, P = 0.05), central corneal thickness (β = 0.02, P < 0.001), and reduced maximum keratometry (β = −0.39, P = 0.010).

The mean CH and CRF values were low in this sample of the Iranian population aged over 60 years indicating the weaker elasticity of the corneal connective tissue.

Coronavirus disease 2019 (COVID‑19) quickly spread to the world, causing a pandemic. While some studies have found no link between opioid use disorder (OUD) and COVID‑19, the role of opioid on COVID‑19 is challenging. The present study aimed to determine the relationship between OUD and COVID‑19.

This was a prospective cohort study. We used data from the third phase of the Shahroud Eye Cohort Study on 4394 participants which started in September 2019 and ended before the COVID‑19 epidemic in Shahroud in February 2020. The participants were followed for about 13 months till March 26, 2021. COVID‑19 was detected by RT‑PCR on swap samples from the oropharynx and nasopharynx. The incidence of COVID‑19 compared in OUD and non‑OUD participants, and relative risk was calculated in log‑binomial regression models.

Among the 4394 participants with a mean age of 61.1 years, 120 people had OUD. The incidence of COVID‑19 in participants with OUD and non‑OUD was 4.17% and 6.22%, respectively (P‑value: 0356). The relative risk of OUD for COVID‑19 was 0.60 (95% confidence intervals: 0.25–1.44; P value: 0.251).

OUD was not associated with COVID‑19. The claim that people with OUD are less likely to develop COVID‑19 is not supported by these data.

Understanding the area of study stimulates the student. Therefore, students should pick their field of study with more information so that they get more engaged in it to complete the responsibilities assigned in the future as well as possible. The purpose of this study was to ascertain the attitude of Shiraz University of Medical Sciences environmental health students regarding their field of study and potential future careers.

This study was a cross-sectional, descriptive research study on medical education. In this study, 120 students studying environmental health engineering at Shiraz University of Medical Sciences had their attitudes and knowledge assessed using a questionnaire created by the University of Minnesota, America, and the results were then analyzed using chi-square and t-tests.

According to the research's findings, more than 80% of students chose their field of study without having any prior knowledge of it, more than 90% did not place it among their top priorities, and 80% claimed that their field of study depended on whether or not their employment position is acceptable.

According to the data, the majority of students had an unfavorable perception about entering this field. As a result, it is necessary to thoroughly present this discipline to students before they begin studying it, as well as to update its subject headings to better meet societal demands.

Coronavirus disease 2019 (COVID-19) is a viral infection caused by SARS-CoV-2, first recognized in China and quickly became a global pandemic. The COVID-19 pandemic has been found to have positive and negative environmental impacts. Air, wastewater, and solid waste are some examples that show this pandemic’s consequences. The current review summarizes the interactions between the COVID-19 pandemic with air, water, wastewater, and solid waste. During the COVID-19 outbreak, air pollution, ambient noise, fuel, and energy consumption, have been reduced. On the other hand, air pollution has been shown to increase the risk of COVID-19; thus, there is a positive correlation between air pollution and the number of COVID- 19 cases. Moreover, the researchers have detected the SARSCOV- 2 in feces and wastewater. Therefore, exposure to SARSCoV- 2 is possible by utilizing untreated effluent and wastewater in irrigation or aerosol generation during specific wastewater treatment processes. Furthermore, monitoring SARS-CoV-2 in the wastewater allows us to detect the virus before it spreads in the community take the necessary measures, and implement effective policies. Changes in the composition and quantity of municipal solid waste (MSW) are typical results of the COVID-19 pandemic, as plastic waste generation has increased globally due to the higher use of disposable single-use plastic bags and packaging. Mixing infectious virus-infected waste with domestic waste has led to the terminus of waste recycling in many parts of the world due to its hazardous potential. Developing effective strategies based on the sustainable development approach may reduce the adverse effects of the COVID-19 pandemic and similar outbreaks in the future.

To investigate the prevalence of Meibomian gland dysfunction (MGD) and its relationship with some determinants in underserved villages of Iran. This population-based cross-sectional study was conducted on 3850 subjects that were randomly selected from the villages of two underserved districts in the north and southwest of Iran using multistage cluster sampling. All participants underwent complete ophthalmic examinations, including visual acuity and refraction measurement. Then, slit-lamp biomicroscopy was done by an ophthalmologist to investigate MGD. Of 3850 subjects that were invited, 3314 participated in the study (participation rate=86.07%), of whom 1834 (55.34%) were women. The mean age of the participants was 37.7±21.4 years (range=2-93 years). The prevalence (95% CI) of MGD in at least one eye was 29.20% (27.35 to 31.06). According to the results of multiple regression analysis, MGD had a positive association with the male sex (OR: 1.75; CI 95%: 1.44 to 2.13), age 61-70 years (OR: 7.15; CI 95%: 3.65 to 14.01), and living in southern villages (OR: 1.82; CI 95%: 1.48 to 2.22) and an inverse association with education level (OR: 0.89; CI 95%: 0.80 to 0.98). The results of this study showed a lower prevalence of MGD even in Iranian rural regions compared to other Asian countries. This study found that older age, male sex, and low education level served as MGD risk factors. It seems that improved health conditions are an important factor in preventing MGD.

To determine the relationship between road accidents with visual acuity, refractive errors, visual field, and contrast sensitivity.

This population-based case–control study was conducted on roads leading to Tehran Province, Iran. The case group comprised drivers who had met with accidents and were at fault for the accident. The cases were selected in an ongoing manner (incidence cases). The controls were drivers who were the opposing victims in the same. After an initial interview, optometric and ophthalmic examinations including the measurement of visual acuity, refraction, visual field assessment, contrast sensitivity measurement, and slit lamp biomicroscopy were performed for all study participants.

In this study, 281 and 204 individuals were selected for the case and control groups. The mean uncorrected visual acuity was 0.05 ± 0.12 and 0.037 ± 0.10 logMAR in the case and control groups, respectively (P = 0.095). Of the participants in the case and control groups, 32.8% and 23% had a visual field defect in at least one eye, respectively (adjusted odds ratios [aOR] = 1.63, 95% confidence interval [CI]: 1.08–2.48; P = 0.021). Moreover, 16.2% of the cases and 8.3% of the controls had visual field defects in both eyes (aOR = 2.13, 95% CI: 1.17–3.86; P = 0.012). Contrast sensitivity was worse in the case group in all spatial frequencies under non-glare conditions. However, under glare conditions, the contrast sensitivity was significantly worse in the case group only in the spatial frequency of 12 cycles per degree (cpd).

Reduced contrast sensitivity, especially under non-glare conditions, and visual field defects are risk factors that influence the prevalence of road accidents. It is strongly advised that special attention be paid to these visual functions in legal assessments to apply the necessary interventions in individuals with these types of disorders.

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.

Air pollution from industrial sources is a growing problem increasing the amount of air pollution by emitting various gaseous pollutants such as Nitrogen Oxides (NOx ). This study analyzed Nitrogen dioxide (NO2 ) emissions using American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) from the stacks and flares of a gas refinery in the Middle East.

The NO2 emissions were measured from the stacks and flare of the refinery (231 samples). The distribution of emissions was investigated over a statistical period of 1 year for an average time of 1 h using the AERMOD dispersion model in an area of 25×25 km2 . The predicted concentrations were compared with national and international standards and are plotted for the desired zones.

Comparison of simulation results with national and international clean air standards showed that NO2 emission modeled in all periods of 4 seasons is higher than the standard. Examination of NO2 emission and distribution maps also showed that the maximum concentration of NO2 pollutants occurred in the central parts and the area close to the refinery. The highest maximum concentration of 1-h NO2 was 3744.3716 μg/m3 in summer in the west and south of the refinery. Validation results also showed a high correlation between the predicted and actual results.

The power of resources in emission and distribution, topographic conditions, and meteorological characteristics of the region are three important and influential factors in the distribution of NO2 pollutants. So pollution reduction strategies are needed due to the different types of use, surrounding residential areas, personnel, and people involved in the gas refining company

To evaluate the total corneal thickness distribution pattern using a high‑resolution spectral‑domain optical coherence tomography (HR SD‑OCT) for distinguishing normal eyes from keratoconus (KCN).

One hundred and forty‑four patients were enrolled in three groups (55 normal, 45 mild KCN, and 44 moderate‑to‑severe KCN eyes) in this prospective diagnostic test study. Total corneal thickness was measured in 8 semi‑meridians using HR SD‑OCT (Heidelberg Engineering, Heidelberg, Germany) in 5 and 7 mm zones. The central corneal thickness (CCT), corneal focal thinning (minimum thickness[Min], min minus median and maximum [Min‑Med, Min‑Max]), and asymmetry indices (inferior minus superior[I‑S] and supranasal minus infratemporal[SN‑IT]) were calculated. One‑way analysis of variance and the area under the receiver operating characteristic curve (AUC) were used for the analysis.

Thinner CCT, lower Min thickness, more negative Min‑Max, Min‑Med, and greater I‑S and SN‑IT were found in KCN eyes compared to the control group (P < 0.001). The inferior and IT semi‑meridians were the thinnest locations in KCN cases in the 5 mm central zone (P < 0.001). CCT followed by Min‑Med had the highest discriminative ability for differentiating mild KCN (AUC, sensitivity and specificity: 0.822, 87.0%, 60.37% and 0.805, 82.93%, 66.0%, respectively) and moderate‑to‑severe KCN (0.902, 87.82%, 73.08% and 0.892, 85.37%, and 78.85%, respectively) from normal corneas.

The inferior and IT sectors of the cornea with the largest thickness changes in the 5 mm zone are the most common thinning sites in keratoconic corneas, and CCT and Min‑Med are the most sensitive indices for the diagnosis of KCN.

Although neurologic involvement and neuroimaging abnormalities have been frequently identified in COVID-19 patients, the underlying factors remain unclear. In this study, we assessed the association of the neurological manifestations and neuroimaging features of hospitalized COVID-19 patients with their clinical, laboratory, and imaging characteristics.

This multicenter cross-sectional study was conducted between September 2020 and March 2021 at two large academic hospitals in Tehran, Iran. We used census sampling from medical records to enroll hospitalized patients with a positive COVID-19 Polymerase chain reaction (PCR) test who underwent brain imaging due to presenting any acute neurologic symptom during hospital stay.

Of the 4372 hospitalized patients with COVID-19, only 211 met the inclusion criteria (35.5% with severe infection). Central nervous system and psychiatric manifestations were significantly more common in severe cases (p ≤ 0.044). Approximately, 30% had a new abnormality on their neuroimaging, with ischemic (38/63) and hemorrhagic (16/63) insults being the most common. The most frequent reasons that provoked cranial imaging were headache (27%), altered consciousness (25.6%), focal neurologic signs (19.9%), and delirium (18%). Analysis revealed a positive correlation for age, neutrophilia, lymphopenia, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) with the emergence of neuroimaging abnormalities (p ≤ 0.018). In addition, patients with new neuroimaging abnormalities had a significantly higher lung CT score than those without any pathologic findings (11.1 ± 4.8 vs. 5.9 ± 4.8, p < 0.001).

Approximately 30% of the study population had various acute neuroimaging findings. The lung CT score, neutrophil count, and age were strong predictors of acute neuroimaging abnormalities in hospitalized COVID-19 patients.

To determine the repeatability of corneal densitometry measured by the Scheimpflug imaging system.

This cross‑sectional study was conducted on photorefractive keratectomy candidates. One eye of each participant underwent imaging using Pentacam HR three times, 10 min apart. The repeatability of densitometry measurements was evaluated in four concentric annuli around the corneal apex and in different corneal depths. The repeatability of the measurements was evaluated using the intraclass correlation coefficient(ICC), repeatability coefficient (RC), and coefficient of variation (CV). The difference of repeatability between layers and zones was tested by tolerance index (TI).

Sixty eyes of sixty patients with a mean age of 27.76 ± 3.93 years were studied. Half of the participants were female (n = 30, 50%). ICC was above 0.9 in all corneal parts. The posterior layer and central zones showed the least variability of densitometry measurements considering the CV values. The RC was 2.06, 1.17, and 0.92 in anterior, central, and posterior layers, respectively. The RC was 0.88, 0.71, 1.51, and 4.56 in 0–2, 2–6, 6–10, and 10–12 mm circles, respectively. Only the reliability of densitometry in 10–12 mm annulus was statistically lower than the central zone (TI = 0.71).

Corneal densitometry measurements provided by the Pentacam had good repeatability. The repeatability of densitometry measurements decreased from the center to the periphery (with an exception for 0–2 mm and 2–6 mm) and from the posterior to the anterior of the cornea. The reliability of the 10–12 mm zone was markedly less than other zones.