Agreement of anterior segment parameters measured by Scheimpflug-based Scansys and Pentacam HR: A prospective, cross-sectional comparative study.

OBJECTIVE

This study aimed to systematically evaluate the repeatability, differences, and agreement between Scansys and Pentacam HR for measuring anterior segment parameters.

METHODS

This prospective consistency evaluation study evaluated 222 patients' right eyes at our hospital from October to December 2025, analyzing anterior segment parameters with Scansys and Pentacam HR through three scans per eye. Measurement repeatability for both devices was assessed. Differences between devices were analyzed, and agreement was evaluated.

RESULTS

Both Scansys and Pentacam HR demonstrated excellent measurement repeatability (ICC >0.9). No significant differences were observed in corneal curvature between the two devices. Although significant differences in corneal thickness, horizontal white-to-white (HWTW), anterior chamber depth (ACD), anterior chamber angle, and corneal volume were noted, these were clinically insignificant. Meanwhile, Q value, pupil diameter (PD), and anterior chamber volume (ACV) were significantly different. Agreement analysis showed that key parameters (corneal curvature, corneal astigmatism, corneal thickness, and corneal volume) demonstrated excellent agreement between devices (ICC >0.9; narrow 95% limits of agreement). However, agreement was poor for corneal asphericity, ACV, and PD (ICC <0.75). HWTW and ACD showed good agreement, but their 95% limits of agreement were wide.

CONCLUSION

Scansys has good stability, and its measurements of corneal curvature and thickness align well with Pentacam HR, allowing safe interchange. However, parameters like corneal asphericity, ACV, and PD show poor consistency and should not be used interchangeably. Caution is warranted when using HWTW and ACD interchangeably in high-precision applications. Taken together, this study supports rational device selection in clinical practice.