title: Prevalence of Corneal Astigmatism in an NHS Cataract Surgery Practice in Northern Ireland.
abstract: OBJECTIVE
  Post-operative corneal astigmatism following cataract surgery can leave the patient with visual impairment. Correcting it at the time of surgery with a toric intraocular lens (TIOL) can give patients a better final visual outcome. The purpose was to determine the prevalence of corneal astigmatism in a cataract population and assess the demand for TIOL.
  
  
  METHODS
  Keratometric data was collected and analyzed for all patients who attended for routine cataract surgery under the care of a single surgeon based in Altnagelvin Area Hospital, Northern Ireland (NI). All patients were included between January 2008 and December 2014. Data was collected retrospectively for this observational study.
  
  
  RESULTS
  There were 2080 consecutive eyes of 1788 patients. The mean corneal astigmatism was 1.09 ± 0.83. Corneal astigmatism was 1.50D or less in 1621 eyes (78%). It was more than 2.00 D in 242 eyes (11.6%), more than 2.50 D in 127 eyes (6.1%), more than 3.00D in 68 eyes (3.27%) and more than 3.50 D in 45 eyes (2.16%).
  
  
  CONCLUSIONS
  For routine cataract surgery, 41.3% of eyes had more than 1.00 D of corneal astigmatism and 11.6% had more and 2.00D. Females had more astigmatism than males. This shows the potential demand for the TIOL in this population.
authors.affiliation: Department of Ophthalmology, Ward 28, Royal Victoria Hospital, 274 Grosvenor Road, Belfast, BT12 6BA.
authors.forename: David S
authors.initials: DS
authors.lastname: Curragh
authors.affiliation: Altnagelvin Area Hospital, Western Health and Social Care Trust, Glenshane Road, Londonderry, BT47 6SB.
authors.forename: Patrick
authors.initials: P
authors.lastname: Hassett
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000453:epidemiology* / Q000601:surgery; D002386:Cataract / Q000453:epidemiology*; D002387:Cataract Extraction; D015897:Comorbidity; D005260:Female; D006801:Humans; D007910:Lenses, Intraocular / Q000600:supply & distribution; D008297:Male; D008875:Middle Aged; D009660:Northern Ireland / Q000453:epidemiology; D012189:Retrospective Studies; D013222:State Medicine / Q000706:statistics & numerical data; D014792:Visual Acuity; D055815:Young Adult
keywords: Astigmatism; Cataract; NHS; Northern Ireland; Toric IOL