title: Analysis of anterior corneal astigmatism before cataract surgery using power vector analysis in eyes of Korean patients.
abstract: OBJECTIVE
  To analyze the pattern of anterior corneal astigmatism before cataract surgery in Korean patients using power vector analysis and to assess the effect of aging on astigmatism.
  
  
  METHODS
  Seoul St. Mary's Hospital, Catholic University of Korea, Seoul, South Korea.
  
  
  METHODS
  Cross-sectional retrospective study.
  
  
  METHODS
  The study evaluated eyes with cataract from May 1, 2009, to July 1, 2013. All eyes received a complete ophthalmologic examination and manual keratometer measurement (OM-4) preoperatively. Power vector J0 and linear regression analyses were used to assess the association between age and anterior corneal astigmatism.
  
  
  RESULTS
  The study evaluated 2847 right eyes (2847 patients). The mean age of the patients was 66.64 years ± 12.06 (SD) (range 20 to 100 years); 64.2% of the patients were women. The corneal J0 vector values became progressively negative and trended toward against-the-rule (ATR) astigmatism with increasing age (for men, r = -0.388 and P < .001; for women, r = -0.348 and P < .001). The ATR shift occurred earlier in men than in women. The regression coefficient of J0 values analyzed by age was -0.014 in men and -0.015 in women (both P < .001).
  
  
  CONCLUSIONS
  Anterior corneal astigmatism in Korean patients with cataract shifted with age from with-the-rule to ATR in both sexes.
  
  
  BACKGROUND
  No author has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: From the Catholic Institute for Visual Science (Oh, Joo), College of Medicine, Catholic University of Korea, the Department of Visual Optics (Kim), Baekseok University, Cheonan, and the Department of Ophthalmology and Visual Science (Lee, Hwang, Joo), Seoul St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea.
authors.forename: Eun-hye
authors.initials: EH
authors.lastname: Oh
authors.affiliation: From the Catholic Institute for Visual Science (Oh, Joo), College of Medicine, Catholic University of Korea, the Department of Visual Optics (Kim), Baekseok University, Cheonan, and the Department of Ophthalmology and Visual Science (Lee, Hwang, Joo), Seoul St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea.
authors.forename: Hyojin
authors.initials: H
authors.lastname: Kim
authors.affiliation: From the Catholic Institute for Visual Science (Oh, Joo), College of Medicine, Catholic University of Korea, the Department of Visual Optics (Kim), Baekseok University, Cheonan, and the Department of Ophthalmology and Visual Science (Lee, Hwang, Joo), Seoul St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea.
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Lee
authors.affiliation: From the Catholic Institute for Visual Science (Oh, Joo), College of Medicine, Catholic University of Korea, the Department of Visual Optics (Kim), Baekseok University, Cheonan, and the Department of Ophthalmology and Visual Science (Lee, Hwang, Joo), Seoul St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea.
authors.forename: Kyu-yeon
authors.initials: KY
authors.lastname: Hwang
authors.affiliation: From the Catholic Institute for Visual Science (Oh, Joo), College of Medicine, Catholic University of Korea, the Department of Visual Optics (Kim), Baekseok University, Cheonan, and the Department of Ophthalmology and Visual Science (Lee, Hwang, Joo), Seoul St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea. Electronic address: ckjoo@catholic.ac.kr.
authors.forename: Choun-Ki
authors.initials: CK
authors.lastname: Joo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D044466:Asian People / Q000208:ethnology; D001251:Astigmatism / Q000175:diagnosis / Q000208:ethnology / Q000503:physiopathology*; D002386:Cataract / Q000503:physiopathology*; D002387:Cataract Extraction; D003315:Cornea / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D057234:Preoperative Period; D012044:Regression Analysis; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012737:Sex Factors; D055815:Young Adult