Randomized prospective comparison of visian toric implantable collamer lens and conventional photorefractive keratectomy for moderate to high myopic astigmatism

J Refract Surg. 2007 Nov;23(9):853-67.


Purpose: To compare the Visian Toric Implantable Collamer Lens (TICL), a toric phakic intraocular lens (IOL), and photorefractive keratectomy (PRK) in the correction of moderate to high myopic astigmatism.

Methods: This prospective, randomized study consisted of 43 eyes implanted with the TICL (20 bilateral cases) and 45 eyes receiving PRK with mitomycin C (22 bilateral cases) with moderate to high myopia (-6.00 to -20.00 diopters [D] sphere) measured at the spectacle plane and 1.00 to 4.00 D of astigmatism. All patient treatment and follow-up occurred at the Naval Medical Center San Diego. Study follow-up was 1 day, 1 week, 1, 3, 6, and 12 months postoperative.

Results: Mean best spectacle-corrected visual acuity (BSCVA), change in BSCVA, proportion of cases with improvement of 1 or more lines of BSCVA, proportion of cases with BSCVA and uncorrected visual acuity (UCVA) 20/12.5 or better, proportion of cases with BSCVA and UCVA 20/16 or better (6 months, 88% vs 54%, P=.002), and predictability +/-1.00 D (6 months, 100% vs 67%, P<.001) were all significantly better in the TICL group than the PRK group at all time periods studied postoperatively. Similarly, contrast sensitivity, tested at both the 5% photopic level and the 25% mesopic level, was significantly better at all postoperative time points in the TICL group. Mean spherical equivalent refraction was closer to emmetropia (0.28+/-0.41 vs 0.76+/-0.86, P=.005), and predictability +/-0.50 D and stability of manifest refraction (+/-0.50 D and +/-1.00 D) were significantly better in the TICL group at all postoperative visits through 6 months. Mean astigmatism correction at 6 months was not significantly different between the two groups (0.52+/-0.33 vs 0.46+/-0.35, P=.450).

Conclusions: The TICL performed better than PRK in all measures of safety (BSCVA), efficacy (UCVA), predictability, and stability in this comparison, supporting the TICL as a viable alternative to existing refractive surgical treatments.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Astigmatism / complications
  • Astigmatism / physiopathology
  • Astigmatism / rehabilitation
  • Astigmatism / surgery*
  • Contrast Sensitivity
  • Eyeglasses
  • Female
  • Follow-Up Studies
  • Humans
  • Lasers, Excimer
  • Lens Implantation, Intraocular* / adverse effects
  • Male
  • Myopia / complications
  • Myopia / physiopathology
  • Myopia / rehabilitation
  • Myopia / surgery*
  • Phakic Intraocular Lenses* / adverse effects
  • Photorefractive Keratectomy* / adverse effects
  • Postoperative Period
  • Predictive Value of Tests
  • Refraction, Ocular
  • Severity of Illness Index
  • Treatment Outcome
  • Visual Acuity