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Background and Objective: Several studies have reported high prevalence of severe lack of cobalamine and Folate in aged people. The most important causes are: malnutrition, atrophic gastritis and drug use. Age related macular degeneration (ARMD) is a primary degenerative disorder of central retinal area with loss of visual acuity. Recent studies have shown a significant relationship between age related macular degeneration and lack of plasma level of Folate, red blood cells and cobalamine. This study was caried out to investigate the relationship between age related macular degeneration and plasma Folate, Cobalamine and photostress recovery time, in elderly population. Materials and Methods: This case – control study was done on 124 elderly population. The participants were collected from by cluster sampling in mashhad located in the Noth – East of Iran during 2006. The patients underwent eye examination including indirect ophthalmoscopy. Slit lamp examination and photostress recovery time for age related macular degeneration by an ophthalmologist. After blood sampling, plasma Folate, serum Cobalamine, were determined by RIA method (DRG kit). Results:The Mean+-SD of cobalamin and folate in age related macular degeneration patients was 298.848+-288.66 pg/ml and 5.543+-3.58 ng/ml and in normal group was 310.775+-531.38 pg/ml and 5.365+-3.52 ng/ml. There was no significant difference between age related macular degeneration patients and control group. Photostress recovery time was significantly increased in patients with age related macular degeneration (P<0.05). There was no significant relationship between photostress recovery time and Cobalamine and folate level. Conclusion: This study showed that serum cobalamin and folate non significantly is decreased in age related maucular degeneration patients, with increasing photostress recovery time, we can use this screening test for the dignosis of age related macular degenertion.

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Background and Objective: It is well accepted that accommodation system is characterized by steady state error in focus. Usually near addition lenses are prescribed to prepresbyopic individual for treatment of binocular motor problems such as convergence excess and accommodative disorder. The purpose of this study was to evaluate the near addition lenses in accommodative and vergence responses at three viewing distances. Materials and Methods: This semi-experimental study was done on 42 students of 17-25 years old in Zahedan, South-Eastern Iran during 2009. After correction of refractive error, phoria states with APCT and binocular and monocular lag of accommodation by MEM method with and without +2.00 lenses in three difference distances (30, 40, 50 cm) was measured. Data analyzed by ANOVA, t-student and paired t-tests. Results: There was significant difference between average of lag of accommodation and phoria at various distances, with and without lens (P<0.05). Also, there was significant difference between mean of lag in 3 fixation distance (P<0.017). There was no significant difference between average of lag of accommodation and phoria at various distances in three group of refractive error. Conclusion: Our results showed that, near addition lens reduce the lag of accommodation. It is proposed, therefore, according to near emmetropization theory addition lenses may be effective in reducing of the myopia progression.

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Background and Objective: Glaucoma is one of the most important cause of blindness wordwide. Exact determination of intra ocular pressure is important for the diagnosis and decision making about glaucoma treatment. Central corneal thickness is considered as effective factor on intra ocular pressure and visual field defect. This study was carried out to determine the relationship between central corneal thickness, intra ocular pressure and visual field in normal tension and primary open angle glaucoma. Materials and Methods: This descriptive study was carried out on 45 eyes with normal tension glaucoma and 45 eyes with primary open angle glaucoma in Al-Zahra ophthalmology hospital in Zahedan, Iran during 2010. Intra ocular pressure and central corneal thickness were measured by Goldman tonometer and pachymeter and visual field exanimated by Humphrey perimeter. Data were analyzed using SPSS-16, paired t-test, ANOVA, Mann–Whitney and Pearson corlateion tests. Results: There was significant correlation between central corneal thickness and intra ocular pressure (r=0.309, P<0.05). A significant difference was detected in intra ocular pressure between two type of glaucoma (P<0.05). Mean value of central corneal thickness in patient with mild visual field defect was higher than severe visual field defect but there was not significant statistical difference between central corneal thickness and visual field defect in subjects with glaucoma. Conclusion: This study indicated that increasing corneal thickness is accompanied with intra occular presure.

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Color vision deficiency (CVD) is a defect of vision with disability to distinguish colors. Color vision deficiency can be divided into the two categories, congenital and acquired. Congenital color vision deficiency divided into anomalous trichromacy, dichromacy and monochromacy. The most common congenital CVD was deuteranomalous that mode of inheritance is X linked recessive occurring mostly in males. Acquired CVD can occur as a direct result of illness or any related medicine. Color perception changes in acquired CVD may be secondary to primary ocular disease, drug side effect, or serious systemic disease such as diabetes. Dystrophy of cone, types of maculopathy, crystalline lens changes associated with aging, diabetes, glaucoma, optic nerve diseases and traumatic brain injuries can cause CVD. For acquired CVD, type of defect may not be easy to classify; nevertheless, predominantly is tritanopia and type and severity of the defect fluctuates during of disease. It has been suggested that human evolution to industrialized civilization has led to an increased prevalence of CVD in most population. An acquired CVD can reflect a deficiency in color information processing at anywhere along the related visual pathway, from the photoreceptors to the cortex. Sometimes, assessment of color vision can be helpful to detect a visual impairment in early stages.

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Background and Objective: Age-related cataract is one of the most important causes of blindness. Early detection of cataracts can help alleviate the problems caused by this disease. This study was performed to evaluate the visual acuity and contrast sensitivity of patients with early cataract.
Methods: This descriptive-analytical study was performed on 54 patients (108 eyes) in the age range of 35 to 50 years with early stage cataract referred to Alzahra Ophthalmology Hospital in Zahedan, souh-west of Iran. The ethnicity of all the participants was Baluchi and Sistani. After correcting the refractive errors if the inclusion criteria were met, visual acuity with E chart at 6 m and Pelli Robson contrast sensitivity chart at 3 m were measured as monocular.
Results: There was a significant correlation between visual acuity and contrast sensitivity (P=0.033, r²=0.205). The mean of visual acuity and contrast sensitivity were not significantly different in the two Baluchi and Sistani ethnicities. But visual acuity and contrast sensitivity were significantly different in the two genders (P<0.05).
Conclusion: Early cataract, although having a minor effect on visual acuity, can reduce contrast sensitivity. Therefore, measuring of contrast sensitivity in normal light condition in patients with early cataract who complain of blurred vision despite normal visual acuity can more accurately assess their visual function.