title: Success rates in the correction of astigmatism with toric and spherical soft contact lens fittings.
abstract: OBJECTIVE
  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.
authors.affiliation: Fatih Sultan Mehmet Education and Research Hospital, Ophthalmology Clinics, Istanbul, Turkey.
authors.forename: Sevda Aydin
authors.initials: SA
authors.lastname: Kurna
authors.forename: Tomris
authors.initials: T
authors.lastname: Sengör
authors.forename: Murat
authors.initials: M
authors.lastname: Un
authors.forename: Suat
authors.initials: S
authors.lastname: Aki