Viscoelastic Effects in Sonoelastography: Impact on Tumor Detectability
نویسندگان
چکیده
The sonoelastographic theory of tumor detection predicts enhanced image contrast as vibration frequency increases. However, the opposite effect is observed when imaging liver lesions at frequencies (200-400 Hz) where strong viscoelastic effects dominate. Mechanical testing was performed and confirmed the viscoelasticity of liver tissue. The time dependence of the stress relaxation suggests a viscoelastic model with a complex modulus which increases monotonically with frequency. It is shown how this model explains the anomalous frequency effect.
منابع مشابه
Vibration sonoelastography and the detectability of lesions.
Vibration sonoelastography has been developed for the detection of hard lesions in relatively soft tissue. The basic concept is to propagate low-amplitude and low-frequency shear waves (with displacements below 0.1 mm and frequencies typically below 1000 Hz) through deep organs, and displaying the vibration response in real-time using advanced color Doppler imaging techniques. A hard inhomogene...
متن کاملQuantitative sonoelastography for the in vivo assessment of skeletal muscle viscoelasticity.
A novel quantitative sonoelastography technique for assessing the viscoelastic properties of skeletal muscle tissue was developed. Slowly propagating shear wave interference patterns (termed crawling waves) were generated using a two-source configuration vibrating normal to the surface. Theoretical models predict crawling wave displacement fields, which were validated through phantom studies. I...
متن کاملMuscle Tissue Characterization Using Quantitative Sonoelastography: Preliminary Results
A quantitative sonoelastographic technique for skeletal muscle tissue characterization is introduced. Experimental data was collected in both ex vivo bovine and in vivo human skeletal muscle tissue. Crawling wave sonoelastographic data was processed using a quantitative technique for estimating local shear wave speed distributions. Results on ex vivo skeletal muscle samples demonstrate shear wa...
متن کاملDetection and three-dimensional visualization of lesion models using Sonoelastography
Sonoelastography is a vibration Doppler technique for imaging the relative elasticity of tissues. Detectability of hard lesions of various sizes has previously been demonstrated in tissue phantoms by our group. Because real tissue differs from phantom material, the injection of formaldehyde in fresh liver tissue is being used as an in-vitro lesion model. Pieces of fresh calf liver were embedded...
متن کاملQuantitative characterization of viscoelastic properties of human prostate correlated with histology.
Quantification of mechanical properties of human prostate tissue is important for developing sonoelastography for prostate cancer detection. In this study, we characterized the frequency-dependent complex Young's modulus of normal and cancerous prostate tissues in vitro by using stress relaxation testing and viscoelastic tissue modeling methods. After radical prostatectomy, small cylindrical ti...
متن کامل