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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.