Abstract
Purpose :
To assess the correlation of optic disc size measurements between two spectral domain optical coherence tomography (SD-OCT) devices with the goal of improving optic nerve head assessment and interpretation especially in the context of glaucoma management.
Methods :
A retrospective analysis of records was conducted using an established database of patients from an academic eye care center in inner-city Chicago, IL, USA. Inclusion criteria required at least one Cirrus (Zeiss, Dublin, California) and one Maestro2 (Topcon Healthcare, Tokyo, Japan) SD-OCT in the past three years, and a clinical examination during the same timeframe with a diagnosis of glaucoma, glaucoma suspect, or normal. The subjects’ SD-OCT reports were reviewed to confirm reasonable quality, with a random 10% subset undergoing an additional quality verification. The optic disc area measurements for both eyes of each subject were recorded for both devices.
Results :
The study cohort included 198 subjects with optic disc area measurements recorded for 183 right eyes and 181 left eyes on both the Cirrus and Maestro SD-OCT. For the right eyes, the mean optic disc area for Cirrus was 2.09 +/- 0.45 mm2 (range=1.01 to 3.68 mm2) and for Maestro it was 2.55 +/- 0.51 mm2 (range = 1.42 to 4.25 mm2). Bland Altman analysis of the right eyes showed a mean bias of 0.46 +/- 0.25 mm2 (95% LOA = -0.03 to 0.95), with the Maestro consistently giving higher disc areas than the Cirrus (Figure 1). This variation was consistent across all disc size levels. Analyses of the left eyes gave similar results to the right eyes. Regression analysis of the Cirrus and Maestro disc area paired values showed a linear relationship with R2 values of 0.765 and 0.794 for the right and left eyes respectively. Categorizing disc size according to small, medium, and large for each device, good agreement was present between devices (77% agreement, kappa=0.65).
Conclusions :
The Topcon Maestro consistently yields larger measurements of optic disc size compared to the Zeiss Cirrus SD-OCT likely attributable to the devices’ distinctive ONH analysis algorithms. Studies have shown that optic disc size plays a role in influencing the progression of glaucoma. Therefore, it is important to consider the specific OCT device utilized when assessing ONH size to ensure accurate and meaningful interpretations.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.