Abstract
Purpose :
Bruch’s membrane opening minimum rim width (BMO-MRW) has been popularly used to evaluate and monitor glaucoma. Neuroretinal rim (NRR) thickness also shared good diagnostic ability. This study investigated repeatability and agreement among multiple NRR thickness acquisitions. We also evaluated its ISNT/IST patterns and effect from axial length (AL).
Methods :
100 eyes (100 healthy subjects) had NRR thickness measured 5 times consecutively. Signal strength was at least 7 with no obvious artifacts. NRR thickness and retinal nerve fiber layer (RNFL) thickness were obtained. An average from all 5 acquisitions was considered as reference standard. The first, average from the first 2, first 3, and first 4 acquisitions were compared with the reference standard. AL was measured using partial coherence interferometry. Correlations between AL and NRR thickness, and RNFL thickness were studied. Number of eyes following the ISNT and IST patterns were counted.
Results :
87 eyes fulfilled the inclusion criteria. Table 1 shows repeatability and coefficient of variation among 5 acquisitions. They demonstrated comparable results. Table 2 shows agreement between different averaging methods with the reference standard. Agreement improved with averaging from more acquisitions. There were significant correlations between superior/inferior RNFL thickness and AL (r=0.28, p=0.008 and r=0.40, p<0.001, respectively). No significant correlations were found between superior/inferior NRR thickness and AL. There was 5% of the eyes following the ISNT pattern using RNFL thickness, and 36% when referring to IST pattern. There was 20% of the eyes following the ISNT pattern using NRR thickness, and 64% when referring to IST pattern.
Conclusions :
One NRR acquisition could provide valid information for clinical use. NRR thickness is less affected by AL for evaluating ganglion cell axons.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.