[Clinical evaluation of different ophthalmic optical coherence tomography devices using a retinal biomimetic phantom]

Objective: To investigate the consistency of different optical coherence tomography (OCT) devices in measuring key retinal parameters. Methods: This study consisted of a cross-sectional study and an experimental study. A total of five OCT devices of different brands (Optovue OCT, Topcon OCT, Intalight OCT, TowardPi OCT, and Zeiss Cirrus OCT) were included, and corresponding devices were selected according to different measurement objects and parameters. Retinal thickness and cup-to-disc ratio were measured in 8 eyes of 4 healthy volunteers recruited from the Department of Ophthalmology, Tianjin Medical University General Hospital, between May and August 2024. In addition, retinal thickness and avascular zone area were measured in retinal biomimetic phantoms. One-way analysis of variance or two-way analysis of variance was used for statistical analysis. Results: The 4 healthy volunteers had a mean age of (31.8±4.8) years, including 3 males and 1 female. Their body mass index was (21.7±1.2) kg/m², ranging from 20.1 to 23.2 kg/m². Differences were observed among OCT devices in retinal thickness measurements of some macular sectors. Using Optovue OCT as the reference, the retinal thicknesses measured in the nasal macular sector of the left eye by Topcon OCT, Intalight OCT, and TowardPi OCT were 98.2%±3.3%, 102.7%±2.6%, and 115.9%±9.4% of the Optovue OCT value, respectively. Pairwise comparisons showed that the TowardPi OCT measurement was significantly higher than those of Optovue OCT, Topcon OCT, and Intalight OCT (95%CI:-0.27 to -0.05, P<0.001; 95%CI: -0.29 to -0.06, P<0.001; 95%CI:-0.25 to -0.02, P=0.006). In retinal biomimetic phantoms, avascular zone area measurements also differed among OCT devices. Using the reference value obtained by the Nikon MM400N measuring microscope as the standard, the measured values were 85.70% for Zeiss Cirrus OCT and 23.50% for Optovue OCT in the superficial foveal avascular zone; in the L-shaped avascular zone, the measured values of the two Intalight OCT devices were 85.30% and 45.80%, respectively. Conclusion: Different OCT devices show differences in measuring some key retinal parameters in healthy subjects and retinal biomimetic phantoms.