Keratoconus in Asians: demographics, clinical characteristics and visual function in a hospital-based population

Clin Exp Ophthalmol. 2011 May-Jun;39(4):299-307. doi: 10.1111/j.1442-9071.2010.02458.x. Epub 2011 May 29.


Background: To describe the demographics, clinical characteristics and visual function of Asian patients with keratoconus managed in a tertiary eye centre.

Design: Prospective cross-sectional study.

Participants: 116 patients with clinically evident or suspected keratoconus (on videokeratography) recruited over 11 months.

Methods: A standardised interview, full ophthalmic examination, refraction and corneal topography were performed. Visual function was assessed with the VF-14 questionnaire.

Main outcome measures: Demographics, clinical characteristics and visual function.

Results: Mean age of our patients was 29.5 ± 9.40 years on enrolment, 62.9% were male, and the ethnic distribution was 60.3% Chinese, 13.8% Malays and 9.5% Indians. Clinically evident keratoconus was present bilaterally in 65 patients (56.0%) and unilateral keratoconus in five patients (4.3%). Five patients (4.3%) had a family history of keratoconus. The majority of patients were managed with contact lenses (60.8%) or glasses (24.5%). Eye rubbing was common (68%) as were asthma (26.3%) and eczema (18.4%). Conical protrusion was the commonest sign (75.3%). The mean cylinder was higher in keratoconus eyes compared with keratoconus suspect eyes (-4.01 vs. -1.27, P < 0.001), and best-corrected visual acuity was poorer (0.19 vs. 0.05, P < 0.001). Unaided visual acuity was significantly worse with increasing age (P = 0.016). On the VF-14, 32% scored 90 or less (out of 100), reflecting difficulties with vision-related daily activities.

Conclusions: Our Asian patients with keratoconus had similar demographic and clinical characteristics to patients in Western populations. Even with apparently good visual acuity, some patients still experience substantial impairment in vision-related activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Asian People / ethnology*
  • Child
  • Corneal Topography
  • Cross-Sectional Studies
  • Female
  • Humans
  • Keratoconus / diagnosis
  • Keratoconus / ethnology*
  • Keratoconus / physiopathology
  • Male
  • Middle Aged
  • Prospective Studies
  • Refraction, Ocular / physiology
  • Sickness Impact Profile
  • Singapore / epidemiology
  • Visual Acuity / physiology
  • Young Adult