Evaluation of parameters for early detection of pediatric keratoconus

Background: Keratoconus in children is often more severe and rapidly progressive compared to adults. While Scheimpflug imaging (Pentacam) improves screening, there are no established pediatric guidelines. Due to challenges in diagnosis, we aimed to correlate clinical factors with abnormal imaging results to aid in the development of screening protocols.

Methods: A single-center retrospective cohort analysis of patients 3-18 years screened for keratoconus with ophthalmic examination and initial Scheimpflug imaging between 2021 to 2023. Scheimpflug indices including final D, ART max, and calculated CAIRO 8, which is a corneal metric combining pachymetry, ART max, and elevation, were compared to published pediatric ranges for normal and keratoconus corneas.

Results: Seventy-eight patients (11.8 ± 3.9 years) were screened with the majority referred due to high and/or progressive astigmatism (74 patients, 94%). Forty-nine patients (63%) were male and 48 (62%) self-reported Hispanic ethnicity. Average astigmatism was 4.9 ± 1.8 D and 86% had with-the-rule astigmatism. Fourteen patients (18%) had corneal findings on slit lamp. Average LogMAR CDVA was 0.243 ± 0.274 D. By Pentacam, 55 (70%) patients had ≥ 1 indeterminate or keratoconus value. Patients stratified as keratoconus by all parameters were older (15 vs. 11 years, p = 0.015-0.02), had worse visual acuity (p < 0.0001), and were more likely to have oblique astigmatism (0.0002-< 0.0001) and corneal abnormalities on examination (p < 0.00001) compared to eyes with normal or indeterminate indices.

Conclusions: Older age, lower visual acuity, oblique astigmatism, and corneal findings were more commonly found in patients with abnormal screening Pentacam. Most patients clinically suspicious for keratoconus had ≥ 1 indeterminate/abnormal indices. Future studies will follow these patients to identify clinical risk factors for progression.