Transmitted ultrasound pressure variation in micro blood vessel phantoms.
Silica, cellulose and polymethylmethacrylate tubes with inner diameters of ten to a few hundred microns are commonly used as blood vessel phantoms in in vitro studies of microbubble or nanodroplet behavior during insonation. However, a detailed investigation of the ultrasonic fields within these micro-tubes has not yet been performed. This work provides a theoretical analysis of the ultrasonic fields within micro-tubes. Numerical results show that for the same tube material, the interaction between the micro-tube and megaHertz-frequency ultrasound may vary drastically with incident frequency, tube diameter and wall thickness. For 10 MHz ultrasonic insonation of a polymethylmethacrylate (PMMA) tube with an inner diameter of 195 microm and an outer diameter of 260 microm, the peak pressure within the tube can be up to 300% of incident pressure amplitude. However, using 1 MHz ultrasound and a silica tube with an inner diameter of 12 microm and an outer diameter of 50 microm, the peak pressure within the tube is only 12% of the incident pressure amplitude and correspondingly, the spatial-average-time-average intensity within the tube is only 1% of the incident intensity.
Qin
Shengping
S
Department of Biomedical Engineering, University of California, Davis, CA, USA. spqin@ucdavis.edu
Kruse
Dustin E
DE
Ferrara
Katherine W
KW
D000465:Algorithms; D000535:Aluminum; D002196:Capillaries / Q000000981:diagnostic imaging*; D002482:Cellulose; D003198:Computer Simulation; D003287:Contrast Media; D004867:Equipment Design; D005898:Glass; D006801:Humans; D045423:Microbubbles; D019047:Phantoms, Imaging; D019904:Polymethyl Methacrylate; D011312:Pressure; D012822:Silicon Dioxide; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*
D003287:Contrast Media; D012822:Silicon Dioxide; D002482:Cellulose; D019904:Polymethyl Methacrylate; D000535:Aluminum