Keratoconus and corneal morphology in patients with Down syndrome at a pediatric hospital

PURPOSE To evaluate patients with Down syndrome for keratoconus and corneal abnormalities using Scheimpflug imaging (Pentacam HR) in a pediatric setting. METHODS The Pentacam scans of patients with Down syndrome seen at Children's Hospital Colorado Ophthalmology Department were reviewed retrospectively, and the following data were collected: keratometry values, pachymetry values, components of the Belin ABCD Grading System, the Belin/Ambrosio enhanced ectasia display D value, and topometric indices, including ISV, IVA, and KI. Subjective interpretation was used to classify scans as normal, abnormal, keratoconus suspect, and definite keratoconus. RESULTS A total of 56 eyes of 31 patients aged 4-24 years (mean, 12.4) were included. The average value for K1 was 44.95 +/- 1.73 D (range, 40.90-49.3 D); for K2, 46.87 +/- 2.16 D (range, 42.50-51.80 D); for Kmax, 48.20 +/- 3.11 D (range, 43-61.7 D); and for Kmean, 45.81 +/- 1.85 D (range, 41.7-50.35 D). Mean pachymetry at the thinnest point was 509 +/- 44.24 mu m (range, 410-612 mu m) and at the apex was 519 +/- 44.24 mu m (range, 412-646 mu m). The mean D value was 2.08 +/- 1.57 (range, 0.08-9.71). There were 10 patients (32%) with either keratoconus suspect or definite keratoconus in at least one eye. CONCLUSIONS We found a high frequency of keratoconus and keratoconus suspect in pediatric and young adult patients with Down syndrome. The corneas in this population had steeper K values and thinner pachymetry values compared to previously reported controls.