Keratoconus in Down syndrome: Prevalence, risk factors, severity and corneal tomographic characteristics

Background This study investigated the prevalence, risk factors and severity of corneal tomographic features of keratoconus in Down syndrome (DS). Additionally, previous studies indicate anomalous corneal features in DS, without keratoconus, this study characterised corneal features in DS without keratoconus. Methods This prospective observational study included participants with DS ≥10 years old. Keratoconus diagnosis, risk factors and corneal tomographic characteristics were recorded. Participants underwent slit‐lamp biomicroscopy, Scheimpflug corneal tomography, corneal topography and autorefraction. A diagnosis of keratoconus (DS‐KC), suspect keratoconus (DS‐SK) and non‐keratoconus (DS‐NK) was made based on expert review of scans by three fellowship trained anterior segment ophthalmologists. Corneal tomography parameters from one eye of each participant were analysed. Results Keratoconus affected 50 (26.3%) of 190 participants, diagnosed by corneal tomography, topography or slit‐lamp signs. Corneal hydrops affected 14.0% of DS‐KC participants. Eye rubbing was a significant risk factor for keratoconus (p = 0.036). 175 (92%) participants could undertake corneal tomography of which tomography assessment alone identified 47 (26.9%) DS‐KC participants, 64 (36.6%) DS‐SK participants and 64 (36.6%) DS‐NK participants. Significant differences (p