Estimating concentration of ultrasound contrast agents with backscatter coefficients: Experimental and theoretical aspects

Sonophoresis Using Ultrasound Contrast Agents: Dependence on Concentration

Sonophoresis can increase skin permeability to various drugs in transdermal drug delivery. Cavitation is recognized as the predominant mechanism of sonophoresis. Recently, a new logical approach to enhance the efficiency of transdermal drug delivery was tried. It is to utilize the engineered microbubble and its resonant frequency for increase of cavitation activity. Actively-induced cavitation ...

Switching of MRI Contrast Agents with Ultrasound

Purpose The utility of (super)paramagnetic agents to enhance contrast in MRI has been for some time demonstrated in human studies. The contrast provided by these agents arises from their ability to achieve reductions in T1 and T2*. Another approach to designing contrast agents is to consider the use of ultrasound (US). We have developed a method involving the application of US in MRI in the pre...

Acoustic backscatter properties of the particle/bubble ultrasound contrast agent.

Bubble-based suspensions with diameters in the 1-5 microns range have been developed for use as ultrasound contrast agents. Bubbles of these dimensions have resonance frequencies in the diagnostic ultrasonic range, thus improving their backscatter enhancement capabilities. The durability of these bubbles in the blood stream has been found to be limited, providing impetus for a number of approac...

An information-theoretic approach to estimating ultrasound backscatter characteristics

Analysis of backscatter in the ultrasound echo envelope, in conjunction with ultrasound B-scans, can provide important information for tissue characterization and pathology diagnosis. Statistical models have often proven useful in modeling backscatter. In this paper, an innovative approach to backscatter analysis based on generalized entropies and neural function approximation is presented. Ent...

Ultrasound Contrast Agents Optical and Acoustical Characterization