Objectives: This study aimed to evaluate the intra-examiner repeatability and inter-examiner reproducibility in lens zonular length measurements using very high-frequency digital ultrasound (Insight 100).
Methods: Two examiners performed ultrasound imaging independently in each subject. The length of temporal and nasal zonules were then measured with a built-in software. Coefficient of variations (CVs) of the three repeated measurements were used to determine intra-examiner variances. Inter-examiner reproducibility was evaluated using intraclass correlation coefficients (ICCs) and the Bland-Altman method.
Results: 40 eyes of 40 subjects (14male and 26female; mean age 23.9 ± 2.4 years) were included in the study. The CVs for intra-examiner measurement were 2.74% temporally and 4.32% nasally for Examiner 1, and were 1.96% temporally and 1.75% nasally for Examiner 2. For inter-examiner reproducibility, all ICCs were above 0.9. However, there were significant differences between the two examiners in temporal zonular length measurements (p = 0.001), and the differences mainly came from measuring the zonular length manually (p = 0.001) rather than recording images (p = 0.480). No significant differences were found between two measurements by the same examiner after one month (all p > 0.05, all ICCs > 0.8).
Conclusion: The Insight 100 device can be used to measure the length of anterior lens zonule with relatively good repeatability and reproducibility.
Clinical trial registration: www.clinicaltrials.gov identifier is NCT05657951.
Keywords: Insight-100; lens zonule; repeatability; reproducibility; very high-frequency ultrasound.