Real-time simulation of musculoskeletal ultrasound from cryosectional anatomy.

BACKGROUND AND OBJECTIVE: Musculoskeletal ultrasound is widely used in clinical practice but remains highly operator-dependent, requiring training in probe manipulation and anatomical interpretation. Existing simulators commonly rely on pre-recorded scans, CT or MRI volumes, synthetic anatomical models, or generative approaches that often fail to reproduce the fine internal tissue structure characteristic of musculoskeletal anatomy. This study proposes a real-time ultrasound simulation method leveraging anatomical microstructure derived from cadaveric cryosection images, with the aim of improving the anatomical fidelity of the resulting ultrasound simulations. METHODS: High-resolution cryosection images are reconstructed into a labeled volumetric dataset representing musculoskeletal structures. Ultrasound image formation is simulated using a ray-tracing approach modeling acoustic attenuation and reflection at tissue interfaces. Speckle patterns are derived from intensity variations in the cryosection textures to improve anatomical fidelity, and tissue-specific acoustic properties modulate reflection, transmission, and attenuation. GPU acceleration enables real-time exploration of probe pose and imaging parameters. Simulated images are compared qualitatively with real ultrasound images and evaluated by clinical experts. RESULTS: The proposed approach produces simulations reproducing characteristic musculoskeletal image features, including layered tissue appearance and speckle patterns consistent with underlying anatomical structures. Expert assessment indicates that simulated images are perceived as anatomically coherent and visually plausible, with interactive performance supporting real-time probe and parameter adjustment. CONCLUSIONS: Cryosection-derived anatomical data as the primary simulation source enables generation of structurally coherent images reflecting real tissue microstructure. The method achieves interactive frame rates, supporting continuous probe exploration, and may provide a useful tool for musculoskeletal ultrasound training applications.