A Comparative Investigation of Prescriptive Ophthalmic Lens Parameters with Iranian National Standards

Document Type : Original article

Authors

1 Professor of Ophthalmology. Faculty of Rehabilitation Sciences. Shahid beheshti University of Medical Sciences, Tehran, Iran (Corresponding author) mghbr31@yahoo.com

2 Ophthalmologist. Shahed University, Tehran, Iran

3 Dept. of Optometry, Faculty of Rehabilitation Sciences. Shahid beheshti University of Medical Sciences, Tehran, Iran

4 MSc in Biostatistics, Faculty of Rehabilitation Sciences. Shahid beheshti University of Medical Sciences, Tehran, Iran

5 MSc Student of MBA. Sharif University of Technology, Tehran, Iran

Abstract

Background and Aim: Wearing spectacles is the most common procedure for correction of refractive error and because of its close relationship with eye; the standards of frame & lens of glasses play a very important role in preventing vision problems. The purpose of this study was to compare spherical & cylindrical power and prismatic effect of plastic ophthalmic lenses with Iranian national standards.
 
Material & Method: In this Cross sectional-Comparative study 48 plastic ophthalmic single vision lenses were inspected & compared with relative national standards i.e.: ISIRI 8715-1:1385.
 
Results: The spherical power factorwith instruments set as step 0.01, all the cases(-1.00,-3.00,-6.00) were in tolerance with limits of the standards (±0.12 D) .The instrument was set for 0.01 step for cylindrical power, at -6.00                                     D 100% of lenses had no cylindrical power. At -3.00 & -1.00 D about 99% were in tolerance with the standards (±0.09 D).
The effect of horizontal & vertical prism, at the power of -6.00 all lenses show prismatic effect but 99% were in tolerance with the standards (±0.85D). At the power of -3.00 & -1.00 D, prismatic effect of lenses were in tolerance with relative standards (±0.55, ±0.35), respectively.
 
Conclusion: All single vision were collected from famous companies showed the quality of passing  all factors of tests & gained Iranian national standards i.e.: ISIRI 8715-1:1385.
 

Keywords

References

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The Scientific Journal of Rehabilitation Medicine
Volume 1, Issue 4 - Serial Number 4
January and February 2013
Pages 8-13

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History

  • Receive Date: 12 February 2012
  • Revise Date: 08 May 2012
  • Accept Date: 30 July 2012
  • First Publish Date: 21 December 2012

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