We have located links that may give you full text access.
JOURNAL ARTICLE
RESEARCH SUPPORT, NON-U.S. GOV'T
Induced astigmatism after photorefractive keratectomy.
Journal of Cataract and Refractive Surgery 1999 Februrary
PURPOSE: To retrospectively analyze a group of patients to determine whether their induced astigmatism was caused by asymmetry in the laser beam, asymmetry in ablation rates, or wound healing in different corneal meridians.
SETTING: Single-center physician office.
METHODS: In this study, 146 eyes of 116 patients who had photorefractive keratectomy (PRK) for myopia with the Apex laser (Summit Technology) were retrospectively identified. In 28 eyes, the patient's chair had been rotated 90 degrees from its usual position under the laser. The vector-summated mean change in astigmatism in eyes with the chair rotated 90 degrees was compared with that in a group of control eyes in which the chair was in the usual position.
RESULTS: The vector-summated mean change in the control eyes was 0.30 diopter (D) at 83 degrees. Forty-eight of 113 eyes (42.5%) had induced with-the-rule (WTR) astigmatism, and 14 of 113 eyes (12.4%) had induced against-the-rule (ATR) astigmatism. In the eyes in which the chair was rotated 90 degrees, vector-summated mean change was 0.10 D at 13 degrees (P < .0005). One of 27 eyes (3.7%) had induced WTR astigmatism, and 13 of 27 eyes (48.1%) had induced ATR astigmatism (P < .001, chi-square).
CONCLUSION: Astigmatism induced by myopic PRK with the Apex laser was small. The axis of induced astigmatism rotated 90 degrees when the patient's chair was rotated, implying that it is inhomogeneities in the beam rather than meridional asymmetry in ablation rates or wound healing that are responsible for induced astigmatism.
SETTING: Single-center physician office.
METHODS: In this study, 146 eyes of 116 patients who had photorefractive keratectomy (PRK) for myopia with the Apex laser (Summit Technology) were retrospectively identified. In 28 eyes, the patient's chair had been rotated 90 degrees from its usual position under the laser. The vector-summated mean change in astigmatism in eyes with the chair rotated 90 degrees was compared with that in a group of control eyes in which the chair was in the usual position.
RESULTS: The vector-summated mean change in the control eyes was 0.30 diopter (D) at 83 degrees. Forty-eight of 113 eyes (42.5%) had induced with-the-rule (WTR) astigmatism, and 14 of 113 eyes (12.4%) had induced against-the-rule (ATR) astigmatism. In the eyes in which the chair was rotated 90 degrees, vector-summated mean change was 0.10 D at 13 degrees (P < .0005). One of 27 eyes (3.7%) had induced WTR astigmatism, and 13 of 27 eyes (48.1%) had induced ATR astigmatism (P < .001, chi-square).
CONCLUSION: Astigmatism induced by myopic PRK with the Apex laser was small. The axis of induced astigmatism rotated 90 degrees when the patient's chair was rotated, implying that it is inhomogeneities in the beam rather than meridional asymmetry in ablation rates or wound healing that are responsible for induced astigmatism.
Full text links
Related Resources
Trending Papers
Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.Journal of Personalized Medicine 2024 Februrary 4
Molecular Targets of Novel Therapeutics for Diabetic Kidney Disease: A New Era of Nephroprotection.International Journal of Molecular Sciences 2024 April 4
Perioperative echocardiographic strain analysis: what anesthesiologists should know.Canadian Journal of Anaesthesia 2024 April 11
The 'Ten Commandments' for the 2023 European Society of Cardiology guidelines for the management of endocarditis.European Heart Journal 2024 April 18
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app