PURPOSE: 4D-visualization of the human upper arm based on sequential or dynamic MRI may be useful in functional orthopedic disorders and surgical planning. A cascade of 4D-visualization approaches have been applied including deformation of the soft tissue surfaces and muscular contraction. Skeletal structures and the epifascial tissue comprising vascular structures are included in the 4D-visualization. METHODS: Sequential MRI (T2-weighted spin echo sequences) scans of a healthy volunteer's upper extremity were obtained. The skeletal, muscular, and epifascial tissues were segmented. For 4D-rendering of the elbow joint, surface models of the humerus, the ulna, and the radius, were displaced with respect to the movement. For 4D-visualization of the soft tissue, the processed MRI data were subjected to highly transparent direct volume rendering with special two-tone transfer functions designed with regard to the application, e.g., muscular inner structure or fasciae. For rendering of time dependent behavior, the visualization was continuously updated. RESULTS: Continuous deformation of muscular inner structure and fasciae, and dynamics of muscle fibers could be differentiated in 4D-visualizations of the upper extremity. Using sequential MRI scans, this work was constrained by the high sagittal slice thickness and separation. CONCLUSION: 4D-visualization of the upper extremity based on sequential MRI is feasible and provides a realistic appearance in comparison with anatomical drawings and preparations. The 4D-visualization method may be useful for detecting and monitoring muscular pathologies and lesions.
PURPOSE: 4D-visualization of the human upper arm based on sequential or dynamic MRI may be useful in functional orthopedic disorders and surgical planning. A cascade of 4D-visualization approaches have been applied including deformation of the soft tissue surfaces and muscular contraction. Skeletal structures and the epifascial tissue comprising vascular structures are included in the 4D-visualization. METHODS: Sequential MRI (T2-weighted spin echo sequences) scans of a healthy volunteer's upper extremity were obtained. The skeletal, muscular, and epifascial tissues were segmented. For 4D-rendering of the elbow joint, surface models of the humerus, the ulna, and the radius, were displaced with respect to the movement. For 4D-visualization of the soft tissue, the processed MRI data were subjected to highly transparent direct volume rendering with special two-tone transfer functions designed with regard to the application, e.g., muscular inner structure or fasciae. For rendering of time dependent behavior, the visualization was continuously updated. RESULTS: Continuous deformation of muscular inner structure and fasciae, and dynamics of muscle fibers could be differentiated in 4D-visualizations of the upper extremity. Using sequential MRI scans, this work was constrained by the high sagittal slice thickness and separation. CONCLUSION: 4D-visualization of the upper extremity based on sequential MRI is feasible and provides a realistic appearance in comparison with anatomical drawings and preparations. The 4D-visualization method may be useful for detecting and monitoring muscular pathologies and lesions.
Authors: Franz Baumann; Pius Brühlmann; Gustav Andreisek; Beat A Michel; Borut Marincek; Dominik Weishaupt Journal: AJR Am J Roentgenol Date: 2005-01 Impact factor: 3.959
Authors: Xiaodong Zhong; Frederick H Epstein; Bruce S Spottiswoode; Patrick A Helm; Silvia S Blemker Journal: J Biomech Date: 2008-01-03 Impact factor: 2.712