Detecting Keratoconus In Adolescents With Ac-Oct

To evaluate the validity in adolescents of an algorithm for keratoconus detection previously developed in adults.  This optical coherence tomography (OCT)-based approach utilizes characteristics of corneal pachymetric and epithelial thickness changes.

Tertiary care refractive surgery center

We retrospectively reviewed charts of patients under the age of 18 and divided them into four groups according to the Belin-Ambrosio display (Pentacam):  normal, manifest, and subclinical keratoconus, as well as normal fellow eyes of keratoconic eyes. Corneal and epithelial thickness maps were evaluated by a human grader. In the first step, if at least one of four parameters (pachymetry minimum, pachymetry minimum-median, pachymetry superonasal-inferotemporal, epithelial superonasal-inferotemporal) exceeded its cut-off value, the eye was considered suspect. In the second step, the combined presence of coincident thinning of total cornea and epithelium as well as concentric epithelial thinning led to the diagnosis of keratoconus.

The study included 19 pediatric keratoconus patients with 29 manifest keratoconic, 3 subclinical keratoconic and 5 normal eyes plus 22 eyes of 11 normal adolescents. This algorithm captured all manifest and subclinical pediatric keratoconic eyes. When we combined all eyes of the keratoconus patients, step 1 had 97.3% sensitivity and step 2 had 100% specificity.

Using this OCT-based approach in adolescents yielded a high level of agreement with the current gold standard, Schleimpflug-tomography. Using them together, potentially also with other examinations, may improve the diagnostic accuracy of KC in the pediatric population. Integration of this approach into the software of the device to facilitate automated evaluations is desired.