Prevalence of abnormal corneas in the United States based on Scheimpflug tomography analytics of a pediatric population

Abstract

Purpose : The goal of this study was to determine prevalence of abnormal corneas in pediatric subjects in the US.

Methods : Children aged 3-18 yrs at a school-based vision clinic were enrolled in an IRB approved, prospective, observational, single center (Illinois Eye Institute at Princeton, Chicago) study. Scheimpflug tomography (Pentacam HR, OCULUS Optikgrate GmbH, Germany) was acquired on each eye during comprehensive exams after obtaining consent. Automated multimetric analysis (Belin/Ambrosio Enhanced Ectasia BAD3, OCULUS Optikgrate GmbH, Germany) was run on each scan and the Final BAD-D (Final D) was derived. There is limited reference to prevalence of keratoconus (KC) as determined by tomography in children, and none in a US based population. The prevalence of KC in the generation 2 Raine Study is 1.2% (1 in 84) using a Final D score >2.6 (derived from Scheimpflug imaging). The BAD3 was designed to separate normal from abnormal corneas using a Final D > 2.69. A Final D of > 2.70 was used to calculate prevalence of abnormal corneas for this study.
The following criteria were used to differentiate normal from abnormal corneas (Table 1): Normal, Final D < 2.00 in both eyes, KC Suspect, Final D = or > 2.00 - < 2.70 in at least one eye, and KC, Final D = or > 2.70 in at least one eye. Statistical analysis was performed with SPSS version 25.0 (IBM Corp., Armonk, NY, USA).

Results : 2212 eyes were screened for this analysis. Subjects > 18 yrs of age or subjects missing data on the Final D measurements were excluded. Among those included, 96.3% (n=2131) were identified as Black or LatinX. (61.9% (n=1369) were Black and 34.4% (n=762) LatinX).

7.7% (n=165) of the total eyes screened, 8.3% (n=114) of the Black and 6.0% (n=46) of the LatinX subjects had a Final D between 2.00 – 2.69 in at least one eye and were assumed KC suspect. 2.3% (n=50) of the total eyes, 2.5% (n=34) of the Black and 1.4% (n=11) of the LatinX population had a Final D = or > 2.70 in at least one eye and were considered keratoconic.

Conclusions : In a primarily Black and LatinX pediatric cohort the prevalence of KC was found to be 2.3% (1 in 50), higher than what has been reported. Patients who are considered keratoconus suspect are important to identify as they require close monitoring. Corneal tomography may be a vital component of pediatric eye exams for early diagnosis and treatment of keratoconus.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.