Back to Journals » Clinical Ophthalmology » Volume 4

Success rates in the correction of astigmatism with toric and spherical soft contact lens fittings

Authors Aydin Kurna S, Tomris S, Ün M, Aki S

Published 20 August 2010 Volume 2010:4 Pages 959—966


Review by Single anonymous peer review

Peer reviewer comments 3

Download Article [PDF] 

Sevda Aydin Kurna, Tomris Şengör, Murat Ün, Suat Aki

Fatih Sultan Mehmet Education and Research Hospital, Ophthalmology Clinics, lstanbul, Turkey

Objectives: To evaluate success rates in the correction of astigmatism with toric and spherical soft contact lens fitting.
Methods: 30 patients with soft toric lenses having more than 1.25 D of corneal astigmatism (25 eyes; Group A) or having 0.75–1.25 D of corneal astigmatism (22 eyes; Group B ) and 30 patients with soft spheric lenses having 0.75–1.25 D of corneal astigmatism (28 eyes; Group C) or less than 0.75 D of corneal astigmatism (23 eyes; Group D ) were included in the study. Corrected and uncorrected monocular visual acuity measurement with logMAR, biomicroscopic properties, autorefractometry and corneal topography were performed for all patients immediately before and at least 20 minutes after the application of contact lenses. ­Success of contact lens fitting was evaluated by three parameters: astigmatic neutralization, visual success, and retinal deviation.
Results: After soft toric lens application, spheric dioptres, cylindric and keratometric astigmatism, and retinal deviation decreased significantly in Groups A and B (P < 0.05). In Group C, spheric dioptres and retinal deviation decreased (P < 0.05), while cylindric and keratometric astigmatism did not change significantly (P > 0.05). In Group D, spheric dioptres, retinal deviation, and cylindric astigmatism decreased (P < 0.05). Keratometric astigmatism did not change significantly (P > 0.05) and astigmatic neutralization even increased.
Conclusions: Visual acuity and residual spherical equivalent refraction remained between tolerable limits with the use of toric and spheric contact lenses. Spherical lenses failed to mask corneal toricity during topography, while toric lenses caused central neutralization and decrease in corneal cylinder in low and moderate astigmatic eyes.

Keywords: astigmatism, soft toric lenses, soft spheric lenses, spherical equivalent refraction, surface topography

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]