evaluation of ocular accommodation, convergence and fusional vergence changes during ramadan

نویسندگان

seyed hosein hoseini-yazdi department of optometry, faculty of rehabilitation, tehran university of medical sciences, tehran, iran

ebrahim jafarzadehpur department of optometry, faculty of rehabilitation, tehran university of medical sciences, tehran, iran

ali mirzajani department of optometry, faculty of rehabilitation, tehran university of medical sciences, tehran, iran

mohsen nematy department of nutrition, faculty of medicine, mashhad university of medical sciences, mashhad, iran

چکیده

purpose: there are a few researches regarding the effects of islamic fasting on visual system. the aim of this study was to investigate the effects of ramadan fasting on the amplitude of accommodation (aa), near point of convergence (npc), positive and negative fusional vergences (pfv and nfv, respectively) in visually healthy fasters. methods: aa, npc, pfv and nfv at far (6m) and near (40cm) were measured in 30 male students. nutritional habits in a week before each examination visit were assessed with the food frequency questionnaire (ffq). results: mean age and fasting average experience were 23.9 and 10 years, respectively. aa and npc showed significant changes (p<0.05) during ramadan; but there was no significant difference before and after ramadan in these parameters. nfv blur, break and recovery points at far significantly reduced in ramadan than before (p=0.003, p=0.005, p=0.003, respectively) with insignificant compensation after ramadan. results showed that there was no significant correlation between changes in diet pattern and aa, npc and distant nfv variations (p<0.05). conclusion: some visual problems may be reported at far and near visual tasks during ramadan; but most of the problems may be resolved after it. some visual preparations may be needed for more effective visual activities during ramadan; essentially for students with intensive visual tasks. vision therapy may be suggested along with nutrient pattern improvement during ramadan.

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عنوان ژورنال:
journal of fasting and health

جلد ۱، شماره ۱، صفحات ۱۳-۱۸

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