Relationship between Viscoelastic and Dielectric Properties of Biological Soft Tissues
A. Bakiya, K. Kamalanand, R. L. J. De Britto in Mechano-Electric Correlations in the Human Physiological System, 2021
Exploring the interrelation between the electrical and mechanical properties of soft tissues in biological system is a subject of great interest to biomedical engineers. In biological soft tissues, the viscoelastic and dielectric properties are well correlated, and variations in the viscoelastic properties can lead to variations in the dielectric properties. The measurement of dielectric properties of soft tissues in vivo is less complicated when compared to the measurement of viscoelastic properties. This chapter presents the analysis of correlation between the dielectric and viscoelastic properties of brain and liver tissue. In addition, this chapter introduces selected machine learning approaches for the prediction of viscoelastic properties of soft tissues using measurements of dielectric properties.
Soft Tissues
Joseph Kovi, Hung Dinh Duong in Frozen Section In Surgical Pathology: An Atlas, 2019
In published frozen section series, the single most frequent soft tissue lesion was metastatic carcinoma. Obviously, metastatic soft tissue lesions will not be presented in this atlas. The second most common entity in soft tissue biopsies was chronic inflammatory processes, and the third were primary soft tissue tumors. Soft tissue sarcomas (STS-s) account for 1% of all malignant neoplasms in the US Obtaining all necessary clinical information is vital for the surgical pathologist who has been requested to render a frozen section diagnosis. The recommended procedure regarding soft tissue specimens in many laboratories of surgical pathology is as follows: a representative portion of the biopsy is processed for frozen section examination. The most common STS-s of adults are liposarcoma and malignant fibrous histiocytoma, whereas, in children rhabdomyosarcoma is the most frequently diagnosed soft tissue tumor. Occasionally, no definite diagnosis can be given from the frozen section of a soft tissue lesion.
Bone and Soft Tissue Tumors
Harry Griffiths in Musculoskeletal Radiology, 2008
The most important parameters in the diagnosis of a bone tumor are the age of the patient, the site of the tumor, and its appearance. Most of them occur on the anterior surface of the tibia where they produce a perpendicular, fluffy periosteal new bone appearance with a soft tissue mass. The radiological appearance of a chondrosarcoma is that of a large soft tissue mass often with a dense bony reaction in the underlying bones, although obviously the tumor can also infiltrate and destroy the bone. The age of the patient is important since most tumors have a fairly limited age range. The classical osteoma occurs in one of the sinuses and is frequently seen in a frontal sinus. Both osteomas and bone islands are entirely benign, and the only reason for operating is for cosmetic reasons or if they obstruct the outlet of one of the sinuses.
Young's Modulus Extraction Methods for Soft Tissue from Ultrasound Measurement System
Published in Instrumentation Science & Technology, 2006
Xingfei Li, Guanglei Wang, Lihong Huang, Guoxiong Zhang
Young's Modulus of soft tissue is a key index to evaluate the biomechanical features of the soft tissue; it has a close relationship to the force and deformation of the soft tissue. In order to measure the force and the deformation of soft tissue, a specially designed device is used to link ultrasound and force transducers by mounting them in series. The combined transducers can simultaneously sense the compressive force and the deformation of the soft tissue. The measurement system is calibrated, before it is used, to collect the data. Based on the measured force and the measured deformation of the soft tissue, the analytics biomechanical model of the soft tissue can be obtained by data fitting. In this paper, the biomechanical model of the soft tissue is assumed to be linear and possess viscous elasticity; when the model of the soft tissue is a linear model, the derived Young's Modulus of the soft tissue is a constant; when the model of the soft tissue is a viscoelastic model, the derived Young's Modulus is a function of the deformation of the tissue. Calibration data show that the maximal error of the measurement system is less than 1.9 µm, non‐linearity error γT is ±0.06%, and the static error band γ is ±0.07%. The measurement system can be used to diagnose the pathology of soft tissue.
Investigation of Soft-Tissue Stiffness Alteration in Denervated Human Tissue Using an Ultrasound Indentation System
Published in The Journal of Spinal Cord Medicine, 2008
Mohsen Makhsous, Ganapriya Venkatasubramanian, Aditya Chawla, Yagna Pathak, Michael Priebe, William Z. Rymer, Fang Lin
Background/Objective: Differences in soft-tissue stiffness may provide for a quantitative assessment and detection technique for pressure ulcers or deep-tissue injury. An ultrasound indentation system may provide a relatively convenient, simple, and noninvasive method for quantitative measurement of changes in soft- tissue stiffness in vivo. Methods: The Tissue Ultrasound Palpation System (TUPS) was used to quantitatively measure changes in soft-tissue stiffness at different anatomical locations within and between able-bodied persons and individuals with chronic spinal cord injury (SCI). The stiffness of soft tissue was measured at the ischial tuberosity, greater trochanter, posterior midthigh, and biceps brachii. Additionally, soft-tissue thickness and soft-tissue deformation were also measured. Results: Significant differences in soft-tissue stiffness were observed within the various anatomical locations tested, in both the able-bodied and SCI groups. Differences in soft-tissue stiffness were also observed between the 2 groups. Participants with SCI had significantly softer tissue in their buttock-thigh area. Conclusions: TUPS is a clinically feasible technology that can reliably and effectively detect changes in soft-tissue stiffness. The study has provided a better understanding of the tissue mechanical response to external loading, specifically in the SCI population, suggesting the use of tissue stiffness as a parameter to detect and assess pressure-related soft-tissue injury.
A Portable Measurement Instrument for Soft Tissue Mechanical Properties
Published in Instrumentation Science & Technology, 2004
Xingfei Li, Sun Ying, Theodor Freiheit
A specially designed device is used to link ultrasound and force transducers by mounting them in series to simultaneously measure the deformation and force in soft tissue. Correlation analysis is used to detect the time of flight (TOF) of the ultrasound through the soft tissue. Data sampling and correlation analyses are performed by FPGA and are realized in the hardware. Based on the biomechanics model of soft tissue and the deformation and force measured, the characteristic parameters of the soft tissue are determined. These parameters and force–deformation curves are displayed on a small LED device. The pathology of the soft tissue can be diagnosed by these parameters and the force–deformation curves. This system is small in volume, light in weight, and easy to use; so, it is convenient for diagnosing disease in soft tissue.