Nesrine Houhat
Technical and Scientific Research Center on Welding and Control (CSC),
Algiers, Algeria Email: n.houhat@csc.dz
Tarek Boutkedjirt
University of Sciences and Technology Houari Boumediene (U.S.T.H.B)
Algiers, Algeria
Email: tarek_boutkedjirt@hotmail.com
« Ultrasonic Backscatter Coefficient Estimates in a Soft Tissue Mimicking Phantom»
The ultimate goal of characterization methods based on the backscatter coefficient (BSC) estimates is to obtain structural information about samples independently of the measurement system. In the current study, measurements of the BSC were obtained from Tissue Mimicking Materials (TMM) or phantoms. These consisted of a mixture of gelatin and distilled water containing microscopic graphite particles with a mean radius of 18 micrometers, which were randomly distributed. Phantoms concentrations ranged from 50 to 200 g of graphite per liter of gelatin. Two BSC estimation methods were used and their results were compared to Faran’s scattering theory which allowed the estimation of the number density of graphite particles in the phantoms. Moreover, measurements of the attenuation coefficient and the ultrasonic propagation velocity in phantoms were performed. The evolution of the attenuation coefficient and the BSC as a function of frequency and scatterers’s concentration in a frequency range from 1.5 MHz to 6 MHz will be presented using two transducers of nominal frequencies 2.25 MHz and 5 MHz. Decreasing of the attenuation coefficient with frequency and graphite concentration will be showed.
Mots clés: Ultrasound, Attenuation, backscattering, TMM.
