title: Comparison of fitting stability of the different soft toric contact lenses.
abstract: OBJECTIVE
  To compare lens orientation and rotational recovery of five currently available soft toric lenses.
  
  
  METHODS
  Twenty subjects were recruited and trialed with each of the study lenses in a random order. Study lenses were PureVision(®) Toric (B&L), Air Optix(®) for Astigmatism (Alcon), Biofinity(®) Toric (CooperVision), Acuvue(®) Advance for Astigmatism (Vistakon), and Proclear(®) Toric (CooperVision). Lens orientation in primary position to determine the lens rotation form the vertical position and rotational recovery to primary gaze orientation following a 45° manual misorientation for the different lenses was compared.
  
  
  RESULTS
  The Biofinity Toric showed the lowest rotation from the vertical position and the Proclear Toric the highest. Also, the highest and the lowest reorientation speed were related to the Biofinity Toric and the Acuvue Advance for Astigmatism, respectively. The Repeated Measures ANOVA showed a significant difference in the lens rotation (P=0.004) and rotational recovery (P<0.001) among different contact lenses and the performed multiple comparisons indicated differences in rotation and also in reorientation speed were only seen between the Biofinity Toric when compared to four other lenses (P<0.05).
  
  
  CONCLUSIONS
  Although there was appropriate fitting, based upon lens orientation and reorientation speed, with each of the study lenses it would appear that the optimized ballast technique used in the design of the Biofinity Toric helps reduce lens rotation and improve rotational recovery compared to others.
authors.affiliation: Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran. Electronic address: hmomeni_opt@yahoo.com.
authors.forename: Hamed
authors.initials: H
authors.lastname: Momeni-Moghaddam
authors.affiliation: School of Life and Health Sciences, Aston University, Birmingham, UK.
authors.forename: Shehzad A
authors.initials: SA
authors.lastname: Naroo
authors.affiliation: Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Farshad
authors.initials: F
authors.lastname: Askarizadeh
authors.affiliation: Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Tahmasebi
mesh_terms: D001251:Astigmatism / Q000503:physiopathology / Q000628:therapy*; D003263:Contact Lenses, Hydrophilic; D005260:Female; D006801:Humans; D008297:Male; D011474:Prosthesis Design; D017755:Prosthesis Fitting; D012029:Refraction, Ocular / Q000502:physiology*; D055815:Young Adult
keywords: Contact lens; Lens design; Lens orientation; Reorientation speed; Rotational recovery; Toric lens