Tear film break-up time influences corneal thickness measurement reliability

Tear film break-up time (TBUT) significantly impacts the repeatability and reliability of corneal and corneal epithelial thickness measurements obtained through anterior segment optical coherence tomography (AS-OCT), according to a study.

The study included 132 eyes from 67 patients, divided into 3 subgroups according to TBUT: Group 1 with TBUT ≤ 5 seconds, Group 2 with TBUT between 5 and 10 seconds, and Group 3 with TBUT > 10 seconds.

Measurements were taken by 2 operators, with each eye imaged 3 times to obtain corneal thickness maps. The results showed that repeatability and reproducibility metrics were influenced by TBUT. Specifically, the repeatability of AS-OCT measurements was lower in Group 1 compared to Groups 2 and 3 (P < 0.05), indicating that poor tear film stability affects measurement accuracy.

Despite this, interoperator differences in corneal epithelial thickness and overall corneal thickness measurements were minimal in most areas.

Reference
Lin K, Xu Z, Wang H, et al. Comparison of the repeatability and reproducibility of corneal thickness mapping using optical coherence tomography according to tear film break-up time. BMC Ophthalmol. 2024;24(1):275. doi: 10.1186/s12886-024-03536-0. PMID: 38970043; PMCID: PMC11227131