rss
Br J Ophthalmol 2005;89:430-436 doi:10.1136/bjo.2004.052688
  • Clinical science
    • Extended reports

Incidence of keratitis of varying severity among contact lens wearers

  1. P B Morgan1,
  2. N Efron1,
  3. E A Hill1,
  4. M K Raynor2,
  5. M A Whiting2,
  6. A B Tullo2
  1. 1Eurolens Research, Department of Optometry, The University of Manchester, UK
  2. 2Royal Eye Hospital, Manchester, UK
  1. Correspondence to: Philip B Morgan Department of Optometry, The University of Manchester, PO Box 88, Manchester M60 1QD, UK; philip.morganmanchester.ac.uk
  • Accepted 29 August 2004

Abstract

Aim: To determine the incidence of non-severe keratitis (NSK) and severe keratitis (SK) among wearers of current generation contact lenses.

Methods: A 12 month, prospective, hospital based epidemiological study was conducted by examining all contact lens wearers presenting with a corneal infiltrate/ulcer to a hospital centre in Manchester. A clinical severity matrix was used to differentiate between NSK and SK, based on the severity of signs and symptoms. The size of the hospital catchment population and the wearing modalities (daily wear (DW) or extended wear (EW)) and lens types being used were estimated from relevant demographic and market data.

Results: During the survey period, 80 and 38 patients presented with NSK and SK, respectively. The annual incidences (cases per 10 000 wearers) for each wearing modality and lens type were: DW rigid—NSK 5.7, SK 2.9; DW hydrogel daily disposable—NSK 9.1, SK 4.9; DW hydrogel (excluding daily disposable)—NSK 14.1, SK 6.4; DW silicone hydrogel—NSK 55.9, SK 0.0; EW rigid—NSK 0.0, SK 0.0; EW hydrogel—NSK 48.2, SK 96.4; EW silicone hydrogel—NSK 98.8, SK 19.8. The difference in SK between EW hydrogel and EW silicone hydrogel was significant (p = 0.04).

Conclusions: A clinical severity matrix has considerable utility in assessing contact lens related keratitis. There is a significantly higher incidence of SK in wearers who sleep in contact lenses compared with those who only use lenses during the waking hours. Those who choose to sleep in lenses should be advised to wear silicone hydrogel lenses, which carry a five times decreased risk of SK for extended wear compared with hydrogel lenses.

Footnotes

    Responses to this article

    • Comment: Incidence of keratitis of varying severity amongst contact lens wearers
      • Fiona Stapleton,
      • Lisa Keay, Katie Edwards, Thomas Navidulath, Cherry Radford, Brien Holden, John Dart
      Br J Ophthalmol published online September 14, 2009
    • Authors' reply
      • Philip B. Morgan,
      • Nathan Efron, Elizabeth A Hil, Mathew K Raynor, Mark A Whiting, and Andrew B Tullo
      Br J Ophthalmol published online September 14, 2009

    This Article

    1. Abstract
    2. Full text
    3. PDF

    Register for free content

    The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

    Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.