Abstract / Summary
Keratoconus (KC) is a progressive ectatic disorder in which stromal thinning and apical protrusion culminate in marked biomechanical decompensation of the cornea. Quantifying these changes in vivo is essential for early detection, monitoring of disease progression, and assessment of therapeutic response. However, conventional optical coherence elastography (OCE) is confounded in vivo by physiological-motion artifacts and by geometric bias inherent to the planar-scan model, which fails to honor the cornea's native curvature. Here, we introduce an air-coupled ultrasound transducer-based OCE (AcUT-OCE) system that couples motion-artifact correction with curvature-aware compensation, enabling robust in vivo elastographic mapping of the diseased cornea. To operationalize both corrections, we constructed a preprocessing pipeline that suppresses physiological-motion phase noise and remaps the lateral coordinate according to corneal curvature. In healthy rabbit corneas, the model-derived effective Young's modulus increased from 7.88 ± 2.19 MPa with conventional planar processing to 9.58 ± 2.63 MPa after combined motion-artifact correction and curvature remapping. This difference demonstrates that the processing strategy materially influences the reconstructed wave speed and effective-modulus estimates. Application of the same workflow to collagenase-induced KC and CXL-treated corneas yielded effective-modulus estimates of 1.93 ± 0.64 MPa for KC, 3.56 ± 0.94 MPa after 15 J/cm 2 CXL, and 8.81 ± 2.01 MPa after 30 J/cm 2 CXL. These results demonstrate distinct biomechanical patterns among healthy, KC, and CXL-treated rabbit corneas. Because the study did not include an independent mechanical reference, the corrected values are interpreted as processing-dependent, model-derived estimates rather than validated absolute material properties.