Kareem, A., Rasheed, G. (2020). The Effect of Posterior Corneal Astigmatism on Ocular Residual Astigmatism in Virgin Eyes. , 20(3), 255-261. doi: 10.52573/ipmj.2020.169728
Alya’a Abood Kareem; Ghazwan Hameed Rasheed. "The Effect of Posterior Corneal Astigmatism on Ocular Residual Astigmatism in Virgin Eyes". , 20, 3, 2020, 255-261. doi: 10.52573/ipmj.2020.169728
Kareem, A., Rasheed, G. (2020). 'The Effect of Posterior Corneal Astigmatism on Ocular Residual Astigmatism in Virgin Eyes', , 20(3), pp. 255-261. doi: 10.52573/ipmj.2020.169728
Kareem, A., Rasheed, G. The Effect of Posterior Corneal Astigmatism on Ocular Residual Astigmatism in Virgin Eyes. , 2020; 20(3): 255-261. doi: 10.52573/ipmj.2020.169728

The Effect of Posterior Corneal Astigmatism on Ocular Residual Astigmatism in Virgin Eyes

Iraqi Postgraduate Medical Journal
Article 8, Volume 20, Issue 3, 2021, Pages 255-261    PDF (182.21 K)
Document Type: Research Paper
DOI: 10.52573/ipmj.2020.169728
Authors
Alya’a Abood Kareem; Ghazwan Hameed Rasheed*
Refractive Department- Ibn Al-Haitham Eye Teaching Hospital - Baghdad-Iraq.
Abstract
 
BACKGROUND:
Ocular astigmatism is the sum of corneal astigmatism and internal astigmatism. The component of ocular astigmatism that cannot be a attributed to the anterior corneal surface is referred to as ocular residual astigmatism.
OBJECTIVE:
To evaluate the difference between ocular residual astigmatism and total ocular residual astigmatism in normal virgin eyes with refractive errors.
PATIENTS AND METHODS:
Eighty four patients ( 135 virgin eyes) with refractive errors were enrolled consecutively in this study at the Lasik clinic in Ibn Al- Haitham Teaching Eye Hospital. Measurement of astigmatism was done by
manifest refraction and corneal topography using Oculus Pentacam, and these measurements were used for calculating ocular residual astigmatism and total ocular residual astigmatism with comparison between them.
RESULTS:
The study showed a significant difference between the means of ocular residual astigmatism (-0.7416 ± 0.4341 ) and the total ocular residual astigmatism (-0.6223 ± 0.401) in with the rule astigmatism (P value < 0.001), and the means of ocular residual astigmatism (-0.8113 ± 0.38517) versus the means
of total ocular residual astigmatism (-0.6658 ± 0.3844) in against the rule astigmatism (P value <0.001).
CONCLUSION:
The ocular residual astigmatism based on the total corneal topographic astigmatism corresponds better with manifest refractive cylinder than the ocular residual astigmatism based solely on anterior corneal
topographic astigmatism .
KEY WORDS: Ocular residual astigmatism, Posterior corneal astigmatism.
 
ABSTRACT:
BACKGROUND:
Ocular astigmatism is the sum of corneal astigmatism and internal astigmatism. The component of ocular astigmatism that cannot be a attributed to the anterior corneal surface is referred to as ocular residual astigmatism.
OBJECTIVE:
To evaluate the difference between ocular residual astigmatism and total ocular residual astigmatism in normal virgin eyes with refractive errors.
PATIENTS AND METHODS:
Eighty four patients ( 135 virgin eyes) with refractive errors were enrolled consecutively in this study at the Lasik clinic in Ibn Al- Haitham Teaching Eye Hospital. Measurement of astigmatism was done by
manifest refraction and corneal topography using Oculus Pentacam, and these measurements were used for calculating ocular residual astigmatism and total ocular residual astigmatism with comparison between them.
RESULTS:
The study showed a significant difference between the means of ocular residual astigmatism (-0.7416 ± 0.4341 ) and the total ocular residual astigmatism (-0.6223 ± 0.401) in with the rule astigmatism (P value < 0.001), and the means of ocular residual astigmatism (-0.8113 ± 0.38517) versus the means
of total ocular residual astigmatism (-0.6658 ± 0.3844) in against the rule astigmatism (P value <0.001).
CONCLUSION:
The ocular residual astigmatism based on the total corneal topographic astigmatism corresponds better with manifest refractive cylinder than the ocular residual astigmatism based solely on anterior corneal
topographic astigmatism .
 
Keywords
Ocular residual astigmatism; Posterior corneal astigmatism
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