فهرست مطالب نگاره یزدانی

Dry eye is one of the most common symptoms among patients who seek for ophthalmologic examination. For this reason, causes, management, methods and the effect of this disease on patients’ quality of life have been broadly studied over the last few years. In this multifactorial disease, ocular surface and tear film are affected which results in instability of tear film and ocular discomfort. There are some risk factors for dry eye disease (DED) including age, gender, systemic medications, autoimmune disorders, low humidity environments and contact lens wear. Information on DED causes may improve diagnosing and managing of this debilitating, chronic condition. In addition to its ocular sign and symptoms, dry eye disease not only has an effect on patients’ visual, social and occupational quality of life, but also patients’ life style can affect the state of this disorder. Among risk factors affecting life style, environmental and occupational factors have been proved to change pre- corneal tear film so that high temperature and low humidity can increase aqua evaporation and lead to ocular discomfort. Indoor and outdoor air pollutants result in visual disturbances due to ocular irritation and DED.Additionally, some personal habits such as sleep quality can also affect tear film stability. In a study which was performed in Japan, a sleep questionnaire was used to subjective measurement of sleep quality and quantity. Their study population were normal office workers. They found that sleep quality consisting: sleep duration, medication, latency or disturbances, is associated with dry eye symptoms. A recent study has shown the effect of sleep position on the ocular surface, so that sleeping in supine position may reduce the symptoms in dry eye patients.Ocular discomfort due to DED may result in ocular fatigue which increases the need of patients for more break times and deterioration of working performance and human faults. Given that not trying to alleviate eye symptoms caused by DED, can have a bad effect on individuals’ performance in workplaces, recognizing the effective factors on eye dryness is very important.

This study aimed to find a relationship between working in petrochemical plants, unusual working hours and dry eye symptoms in petrochemical frontline employees. In this work, we compared a population of petrochemical industry night and day workers with a normal group, in order to assess potential relation of their working environment and sleeping time on their dry eye symptoms. Performing a study on this group of participants allows us to simultaneously assess the effect of outdoor air pollution and working shift on patients’ objective and subjective dry eye signs and symptoms. Identification of key risk factors for DED in symptomatic group can be helpful in better management of this condition.Methods One hundred ninety five males were recruited in this study, and divided into two groups: workers (petrochemical night and day workers) and non- workers (control) group. Day and night workers were working in day and night- time shifts at least for more than 1 year and they had no rotating shifts. Participants with any history of ophthalmic or systemic diseases or ocular surgeries, taking medications which induce dry eye or worsen dry eye symptoms, smoking, contact lens application, lack of sleep (less than 7 hours night sleep for control and day worker groups and less than 7 hours day- time sleep for night workers) and computer users for more than 6 hours a day, were excluded. Socio – economical demographics such as educational level and working experience and salaries were considered. All dry eye examinations were performed in the morning (at least 2 hours after waking up) for day time workers, and in the afternoon (at least 2 hours after a day time sleep) for night workers. Working hours was the same for workers (12 hours working in the field: 8 AM- 8 PM for day time and 8 PM-8 AM for night- time workers). Participants were compared in terms of Schirmer’s test I (without anesthesia), tear break up time (TBUT) and subjective dry eye symptoms (based on DEQ-V questionnaire). The TBUT recorded as the number of seconds that elapse between the last blink and the appearance of the first dry spot in the tear film.  A TBUT under 10 seconds was considered abnormal. For Schirmer’s test the amount of moisture of paper strips were measured and less than 10 mm of moisture in 5 minutes was considered as abnormal.DEQ- V questionnaire consists 5 items for the presence of 3 symptoms of dry eye including: watery eyes (frequency), discomfort (frequency, AM &PM intensity and bother) and dryness (frequency, AM &PM intensity and bother). Other 2 items were: whether the participants have told to have dry eye or they think they have it. The validity of this questionnaire has been evaluated by Chalmers and a total of DEQ score more than 6 can be an indicator of dry eye and needs further clinical tests to confirm DE. Patients with a score of >12 should be referred to be ruled out for Sjӧgren’s Syndrome.After explaining the nature of the study, an informed consent was obtained from each participant The research was approved by the Research Ethics Committee of Mashhad University of Medical Sciences and the protocol adhered to the tenets of the Declaration of Helsinki.

Sixty-five non- workers (control group) and 130 workers (65 night and 65 day- workers) were enrolled in the study. Statistical analysis was performed using SPSS software for Windows version 16 (SPPS, Inc. Chicago, IL). Student t-test and one way analysis of variance (ANOVA) were used to compare means of Schirmer’s test, TBUT and DEQ score among groups. Pearson χ2 test was performed to compare the percentage of abnormal cases in each group.  Bonferroni post hoc corrections were applied for multiple comparisons. For all results p<0.05 was considered as statistically significant. Mean age of participants was 37.44±3.87 years (range 30-45 years). For a better between groups’ comparison considering working shifts, workers were divided in to night and day shift groups and comparison was performed between 3 groups. According to our results, 3 groups were not significantly different regarding age, educational level and working experience (p= 0.218, p=0.884 and p=0.378, respectively). One way ANOVA test showed a significant difference of TBUT between 3 groups (p=0.007). In pairwise comparison, we found that mean TBUT (in seconds) was significantly different between control group and night workers (p= 0.005), but there was no difference between controls and day workers (P=0.181). Although it was greater in day workers, TBUT was not markedly different between night and day workers (P=0.588).Our results showed a significant difference for Schirmer’s test between 3 groups (p<0.001). Multiple comparison of means between groups showed a statistically significant difference between control group and day workers (p=0.002), and also between control group and night workers (p<0.001). The result of the Schirmer’s test between night and day workers was not significantly different (p=0.509).Mean DEQ score was also significantly different between groups (p<0.001) and it was higher in night shift workers. In between group comparison, mean DEQ score was significantly different between controls and night workers (p<0.001). However, mean DEQ score was not markedly different between controls and day- workers or between night and day workers (p=0.053 and p= 0.180, respectively). But it was significantly different between control group and night- workers (p=0.009).The percentage of abnormal findings in all the tests was higher among night workers. However, 3 groups were significantly different just for abnormal DEQ score (P= 0.0.26).Also, in 2 group comparison between workers and non- workers, there was a significant difference in Schirmer’s, TBUT and DEQ results (p<0.001, p=0.004 and p=0.001, respectively).

Both day and night time workers who participated in our study were exposed to pollution from open field petrochemical plants. Day workers’ activities are in higher temperature working hours. On the other hand night shift workers work in lower temperature hours but sleep in unusual hours during the day. This can be the other justification for the lack of significant differences between the results of day and night time workers. Although we recruited participants with at least 7 hours a day sleep but we did not have information about sleep quality of worker and non-workers. Incorporating a sleep quality questionnaire for volunteers can help us to find out if, there is actually any difference in sleep quality of participants in each group besides abnormal sleeping hours. More comprehensive studies on larger population may potentially result in more significant differences among groups. Adding some other dry eye tests including osmolarity test and Ocular Surface Disease Index score to future studies can also be valuable. In addition, recruiting non- residents as control group can better confound intervening factors and results to a more precise comparison between worker and non- worker groups.Working in petrochemical industry plants has an effect on symptoms of dry eye disease in frontline workers. On the other hand, long term working in night shifts seems not to be a key factor for DED. However, these factors should be considered occupationally in order to improve the employees’ performance in workplaces.

To study the effect of colored filters on the reading ability in dyslexic children.

A total of twelve dyslexic children and twelve age and gender matched non-dyslexic children were administered. Following examinations were performed for participants: visual acuity assessment, refraction, evaluating far and near heterophoria, measuring near point of convergence and accommodation, stereopsis, and near fusional reserves. Reading ability was assessed with colored filters and transparent in dyslexic patients. Colored filters were chosen based on Wilkins method (X1 to X16). Filter which improved the reading ability was recorded.

Significant reduction in fusional reserves in dyslexic children compared to normal individuals were observed. (Base in Break p=0.02, Base in recovery, Base Out Break and Base Out recovery p<0.001) However, other visual functions did not differ significantly between the dyslexic and control groups. Colored filters significantly improved word reading ability of dyslexic children. (p=0.0036)

Our findings showed a reduction in fusional reserves in dyslexic children. Reading ability significantly increased in dyslexic children using color filters.

Visual functions are one of the most important factors influencing daily activities of an individual life. Some medications, however, may affect visual function.Methadone is one of the medications used in drug withdrawal both in detoxification and maintenance stages. Evaluation of visual functions in response to continuous use of methadone is essential to increase our understanding of the methadone effects and improve visual care in these patients, which is the goal of the present study.
In this case control study, 30 drug addicts admitted to drug withdrawal clinicswith mean age of 40.97 (SD=9.90) years were divided into two groups. The case group (with methadone consumption of more than six months) contains 20 addicts and control group (with individuals who has just entered the maintenance stage of drug withdrawal) contains 10 addicts. Several visual function examinations performed: visual acuity, contrast sensitivity, visual field, and stereopsis.
In this study, no significant differences were found between groups in static visual acuity and visual field. Contrast sensitivity in 3(p=0.03), 6 (p=0.001), and 18(p=0.00003) cycle per degree frequencies were statistically significant between groups. Stereopsis also reduced in response to prolonged use of methadone (p=0.04). Also, refractive errors in control group were 1D more minus compared to the case group.
Because methadone is used for a long period of time in the maintenance stage of the drug withdrawal, problems caused by this medicine must be considered and necessary visual care in this field should be provided.

To compare the mechanism of illumination contrast sensitivity with color contrast sensitivity.
All articles published in the intended field from the 1956 to 2016 using the search engines including PubMed, Science Direct and Google Scholar was searched. About 100 articles were obtained that by removing duplicate articles and irrelevant ones, finally 40 related articles, were examined, carefully.
The results of relevant studies showed that the contrast sensitivity function curve is band-pass for illumination contrast and low-pass for color contrast sensitivity of visual system. It has also been stated that mechanism of color contrast sensitivity is similar for red and green and different from blue one.
Color contrast sensitivity and illumination contrast sensitivity function are different of the shape of the curve as well as the mechanisms, which would be explained by the multi-channel visual system.

This study was designed to investigate the medical malpractice claims referred to the Board of Appeal of Disciplinary Court in Mashhad Medical Council (MMC). In this descriptive-analytical study, cases referred to the Board of Appeal in the years 2008 to 2013 were reviewed and extracted data were entered into a checklist. During this six-year period, 1943 malpractice claims were initially filed in the Disciplinary Court of MMC. Subsequent to issuing the initial verdict by the Council of Magistrates, after objection of the plaintiff or defendant, or both; 628 cases were referred to the Board of Appeal. The majority of claims were filed against gynecologists (16.1%), followed by orthopedists (13.1%) and general practitioners (12.3%). Most of the verdicts issued by the Council of Magistrates were innocence (46.3%), article “g” (23.5%), and article “b” (11.3%). Appellant in 52.6% of cases were the plaintiff, 39.3% were the defendant and in 8% were both the plaintiff and the defendant. In most cases (83.4%) the initial verdict was confirmed, while in 16.6% cases, the initial verdict was challenged. As a result, after the objection, the number of innocence (non-faulty) verdicts increased by 11.7%. The average time from the moment of submission of the claim till the initial verdict by Council of Magistrates was 147±103 days and the average time from the moment of objection to the initial verdict till the decision of the Board of Appeal was 248±113 days. In this study, it was found that about one-third of the verdicts issued by the Council of Magistrates were objected and referred to the Board of Appeal, but only in about one-sixth of objected cases or one-eighteenth of the total cases, the initial verdict was challenged. Medical community members should respect medical ethics in dealing with patients to achieve their satisfaction and trust; and they should strictly comply with treatment and legal protocols to prevent any legal and penal consequences in case of disease complications and failures in medical procedures.