Purpose
To identify the demographic profile, management and phenotype of Keratoconus (KC) patients referred to the largest governmental tertiary eye institute in Saudi Arabia.
Methods
Retrospective cohort analysis by reviewing charts of 1000 KC patients referred between Jan.-Dec 2010. Amsler-Krumeich classification (based on mean keratometry "K" numbers) was used for staging the disease severity in KC.
Results
The mean age at diagnosis and referral were 21.6 and 28.1 years, respectively. Male to female ratio was 2:1. Central, south and north regions of Saudi Arabia were mostly the main referral regions. Ocular and systemic atopy was present in 25.2%. Mean central corneal thickness was 390 (range, 221-619) um. Staging asymmetry between both eyes in bilateral (95.4%) cases were present in 53.8%. More male patients were significantly diagnosed early in mild stage (stage1; mean K<48D), while, more female patients in advanced one (stage 4; mean K>55D). Advanced stage was significantly diagnosed at a younger age group : 19.76 years. Uncorrected visual acuity decreased with increasing disease staging (better than or equal 20/80 in 46.4% of stage 1, while worse than 20/200 in 39.1% of stage 4). Best corrected visual acuity, with either spectacles or contact lenses (CL), was 20/40 or better in 79.7% of eyes. But only 19.6% total eyes achieved 20/40 with spectacles in comparison to total eyes fitted with CL. Single or combined management modalities for all eyes included: spectacles (15.4%), CL (57.6%), corneal collagen cross-linking (3.9%%), corneal rings (10.6%) and lamellar/penetrating keratoplasty (39.3%). Corneal rings were done for eyes in mild (62%), moderate (35%), and advanced (3%). Sub epithelial and deep stromal scarring was present in 61.2% of eyes required keratoplasties, and 2/3 of which having stage moderate and advanced stages. Male patients tended significantly to have keratoplasty done at 20-30 years, while female patients at more than 30 years of age.
Conclusions
In this hospital-based KC study, the severity is high with an early onset and more rapid progress to advanced stage at a younger age. Female patients had more sever disease. These may be related to genetic and / or environmental factors. The results have implications for KC screening in Saudi Arabia (and probably nearby Middle-Eastern countries), to improve early detection and managment.
Keywords: 574 keratoconus