Measurements of young's modulus of viscoelastic medium using a laser-induced microbubble under acoustic radiation force

2010 ◽  
Author(s):  
Sangpil Yoon ◽  
Salavat Aglyamov ◽  
Andrei Karpiouk ◽  
Seungsoo Kim ◽  
Stanislav Emelianov
Keyword(s):  
Young’S Modulus ◽  
Viscoelastic Medium ◽  
Acoustic Radiation ◽  
Young's Modulus ◽  
Radiation Force ◽  
Acoustic Radiation Force

Quantification of biomechanical properties of human corneal scar using acoustic radiation force optical coherence elastography

2021 ◽  
pp. 153537022110618
Author(s):  
Xiao Han ◽  
Yubao Zhang ◽  
Yirui Zhu ◽  
Yanzhi Zhao ◽  
Hongwei Yang ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Acoustic Radiation ◽  
Ex Vivo ◽  
Young's Modulus ◽  
Radiation Force ◽  
Biomechanical Properties ◽  
Acoustic Radiation Force ◽  
Optical Coherence ◽  
Corneal Surgery ◽  
Corneal Scar

Biomechanical properties of corneal scar are strongly correlated with many corneal diseases and some types of corneal surgery, however, there is no elasticity information available about corneal scar to date. Here, we proposed an acoustic radiation force optical coherence elastography system to evaluate corneal scar elasticity. Elasticity quantification was first conducted on ex vivo rabbit corneas, and the results validate the efficacy of our system. Then, experiments were performed on an ex vivo human scarred cornea, where the structural features, the elastic wave propagations, and the corresponding Young’s modulus of both the scarred region and the normal region were achieved and based on this, 2D spatial distribution of Young’s modulus of the scarred cornea was depicted. Up to our knowledge, we realized the first elasticity quantification of corneal scar, which may provide a potent tool to promote clinical research on the disorders and surgery of the cornea.

Dynamic Analysis of Soft Tissue Viscoelasticity Under Ultrasonic Radiation Force Using FEM

2007 ◽  
Author(s):  
Megan L. Kogit ◽  
Baoxiang Shan ◽  
Assimina A. Pelegri
Keyword(s):  
Finite Element ◽  
Soft Tissue ◽  
Dynamic Analysis ◽  
Young’S Modulus ◽  
Acoustic Radiation ◽  
Young's Modulus ◽  
Radiation Force ◽  
Acoustic Radiation Force ◽  
Damping Coefficient ◽  
Response Data

We have developed a solid mechanics model of nearly incompressible, viscoelastic soft tissue for finite element analysis (FEA) in MATLAB 7.2. Newmark’s method was used to solve the finite element equations of motion for our model. The solution to our dynamic problem was validated with a transient dynamic analysis in ANSYS 10.0. We further demonstrated that our MATLAB FEA qualitatively agrees with those results observed with acoustic radiation force methods on soft tissues and tissue-mimicking materials. We showed that changes in Young’s modulus and the damping coefficient affect the displacement amplitude and phase shift of the response data in the same manner: An increase in Young’s modulus or damping coefficient decreases both the displacement amplitude and response lag. Future work on this project will involve frequency analysis on response data and studying the initial transient region to help uncouple the effects of Young’s modulus and damping coefficient on response characteristics. This will get us one step closer to being able to explicitly determine Young’s modulus and the damping coefficient from the temporal response data of acoustic radiation force methods, which is the ultimate goal of our project.

scholarly journals Estimation of mechanical properties of a viscoelastic medium using a laser-induced microbubble interrogated by an acoustic radiation force

2011 ◽  
Vol 130 (4) ◽  
pp. 2241-2248 ◽  
Author(s):  
Sangpil Yoon ◽  
Salavat R. Aglyamov ◽  
Andrei B. Karpiouk ◽  
Seungsoo Kim ◽  
Stanislav Y. Emelianov
Keyword(s):  
Mechanical Properties ◽  
Viscoelastic Medium ◽  
Acoustic Radiation ◽  
Radiation Force ◽  
Acoustic Radiation Force

scholarly journals Modeling shear waves through a viscoelastic medium induced by acoustic radiation force

2012 ◽  
Vol 28 (6-7) ◽  
pp. 678-696 ◽  
Author(s):  
Kristen H. Lee ◽  
Benjamin A. Szajewski ◽  
Zaegyoo Hah ◽  
Kevin J. Parker ◽  
Antoinette M. Maniatty
Keyword(s):  
Viscoelastic Medium ◽  
Acoustic Radiation ◽  
Shear Waves ◽  
Radiation Force ◽  
Acoustic Radiation Force

Rationale Abklärung von Lebererkrankungen

2017 ◽  
Vol 74 (3) ◽  
pp. 79-86
Author(s):  
Leona von Köckritz ◽  
Andrea De Gottardi
Keyword(s):  
Acoustic Radiation ◽  
Radiation Force ◽  
Acoustic Radiation Force ◽  
Acoustic Radiation Force Impulse ◽  
Alkalische Phosphatase ◽  
Gamma Glutamyltransferase ◽  
Alpha 1 Antitrypsin

Zusammenfassung. Im klinischen Alltag werden häufig erhöhte Leberwerte beobachtet. In der Regel erfordern sie weitere Abklärungen bezüglich der möglichen Ätiologie und des Schweregrad einer akuten oder chronischen Lebererkrankung. Die Abklärung sollte dabei neben einer gezielten Anamnese und sorgfältigen klinischen Untersuchung, auch die Bestimmung von laborchemischen Markern für Cholestase und Leberfunktionsstörungen (wie Alkalische Phosphatase, gamma-Glutamyltransferase, Bilirubin, Albumin und Gerinnungsfaktoren) umfassen. Die Bestimmung weiterer Parameter wie Ferritin und Transferrinsättigung, Autoimmunantikörper, Virusserologien, alpha-1 Antitrypsin und Coerulolasmin können weitere Hinweise für die kausalen Zusammenhänge der Leberfunktionsstörung liefern. Bei Patienten mit Lebererkrankungen ist eine sonografische Beurteilung der Leber obligat. Ergänzend zur Sonografie werden heute weitere nicht-invasive Methoden wie Fibroscan, Acoustic Radiation Force Impulse Elastometrie und Magnet-Resonanz-Elastografie zur Beurteilung der Leberfibrose eingesetzt. In ausgewählten Fällen ist eine Leberbiopsie notwendig, um den Grad der Fibrose und die Ätiologie der Lebererkrankung zu eruieren. Mithilfe eines Fallbeispiels, diskutieren die Autoren im Folgenden die rationale Anwendung diagnostischer Tests und deren korrekte Interpretation und schlagen eine Orientierungshilfe zur rationalen Abklärung von Patienten mit Lebererkrankungen vor.

Sign in / Sign up

Export Citation Format

Share Document