Potential Use of Ultrasonic Cavitation Threshold to Non-Invasively Differentiate Cystic Masses


Objectives: To demonstrate in vitro that changes in ultrasound cavitation threshold might be used for non-invasively distinguishing high viscosity mucinous fluid from low viscosity serous fluid in cystic masses, based on the facts that cavitation threshold increases with increasing viscosity and that cavitation microbubbles are observable with diagnostic ultrasound. Methods: An in vitro model of a cyst was designed using dilutions of ultrasonic gel, and the cavitation threshold of this model was determined using focused and unfocused ultrasound for bubble initiation and clinical ultrasound b-scan for detection. Results: Viscosities of dilutions between 0% and 30% gel were had viscosities measuring between 1.05 ± 0.08 cP and 6600 ± 875 cP. Inertial cavitation in the latter was determined to require an order of magnitude greater intensity, at 1 MHz and 100% duty cycle, than the former (>2.2 W/cm2 vs. <0.19 W/cm2) using unfocused ultrasound. A four-fold increase in the peak negative pressure was required to initiate significant bubble activity using 1.1 MHz and 50% duty cycle focused ultrasound in the 6600 cP fluid compared with the 1 cP fluid. Based on these results, it was estimated that a threshold could be defined that would result in no bubbles in 99.9% of mucinous cysts and just 22% of serous cysts. The remaining 78% of patients presenting with serous cysts would be positively identified by detection of bubbles, and would be spared an unnecessary biopsy. Conclusions: The cavitation threshold may be used non-invasively to distinguish between high viscosity and low viscosity fluids in cysts and reduce biopsies on serous cysts.

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O’Neill, B. , Chang, E. and Yu, N. (2014) Potential Use of Ultrasonic Cavitation Threshold to Non-Invasively Differentiate Cystic Masses. Open Journal of Radiology, 4, 329-338. doi: 10.4236/ojrad.2014.44043.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Spence, R.A.J., Dasari, B., Love, M., Kelly, B. and Taylor, M. (2011) Overview of the Investigation and Management of Cystic Neoplasms of the Pancreas. Digestive Surgery, 28, 386-397.
[2] Scoazec, J.Y., Vullierme, M.P., Barthet, M., Gonzalez, J.M. and Sauvanet, A. (2013) Cystic and Ductal Tumors of the Pancreas: Diagnosis and Management. Journal of Visceral Surgery, 150, 69-84.
[3] Kwon, R.S. (2012) Advances in the Diagnosis of Cystic Neoplasms of the Pancreas. Current Opinions in Gastroenterology, 28, 494-500.
[4] Eastham, R.D. (1954) The Serum Viscosity and the Serum Proteins. Journal of Clinical Pathology, 7, 66-68.
[5] Rosenson, R.S., McCormick, A. and Uretz, E.F. (1996) Distribution of Blood Viscosity Values and Biochemical Correlates in Healthy Adults. Clinical Chemistry, 42, 1189-1195.
[6] Allen, J.S., Roy, R.A. and Church, C.C. (1997) On the Role of Shear Viscosity in Mediating Inertial Cavitation from Short-Pulse Megahertz-Frequency Ultrasound. IEEE Transactions on Ultrasound, Ferroelectrics and Frequency Control. 44, 743-751.
[7] Lai, S.K., Wang, Y.Y., Cone, R., Wirtz, D. and Hanes, J. (2009) Altering Mucus Rheology to “Solidify” Human Mucus at the Nanoscale. PLoS One, 4, e4294.
[8] Lai, S.K., Wang, Y.Y., Wirtz, D. and Hanes, J. (2009) Micro- and Macrorheology of Mucus. Advanced Drug Delivery Reviews, 61, 86-100.
[9] Soo, M.S., Ghate, S.V., Baker, J.A., Rosen, E.L., Walsh, R., Warwick, B.N., et al. (2006) Streaming Detection for Evaluation of Indeterminate Sonographic Breast Masses: A Pilot Study. American Journal of Roentgenology, 186, 1335-1341.
[10] Clarke, L., Edwards, A. and Graham, E. (2004) Acoustic Streaming: An in Vitro Study. Ultrasound in Medicine and Biology, 30, 559-562.
[11] Clarke, L., Edwards, A. and Pollard, K. (2005) Acoustic Streaming in Ovarian Cysts. Journal of Ultrasound in Medicine, 24, 617-621.
[12] Van Holsbeke, C., Zhang, J., Van Belle, V., Paladini, D., Guerriero, S., Czekierdowski, A., et al. (2010) Acoustic Streaming Cannot Discriminate Reliably between Endometriomas and Other Types of Adnexal Lesion: A Multicenter Study of 633 Adnexal Masses. Ultrasound in Obstetrics and Gynecology, 35, 349-353.
[13] Holland, C.K. and Apfel, R.E. (1989) Improved Theory for the Prediction of Microcavitation Thresholds. IEEE Transactions on Ultrasound, Ferroelectrics and Frequency Control, 36, 204-208.
[14] Yang, X. and Church, C.C. (2005) A Model for the Dynamics of Gas Bubbles in Soft Tissue. Journal of the Acoustic Society of America, 118, 3595-3606.
[15] R Development Core Team (2010) R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna.
[16] Hyndman, R. and Fan, Y. (1996) Sample Quantiles in Statistical Packages. The American Statistician, 50, 361-365.
[17] Lewandrowski, K.B., Southern, J.F., Pins, M.R., Compton, C.C. and Warshaw, A.L. (1993) Cyst Fluid Analysis in the Differential Diagnosis of Pancreatic Cysts. A Comparison of Pseudocysts, Serous Cystadenomas, Mucinous Cystic Neoplasms, and Mucinous Cystadenocarcinoma. Annals of Surgery, 217, 41-47.
[18] Leung, K.K., Ross, W.A., Evans, D., Fleming, J., Lin, E., Tamm, E.P., et al. (2009) Pancreatic Cystic Neoplasm: The Role of Cyst Morphology, Cyst Fluid Analysis, and Expectant Management. Annals of Surgical Oncology, 16, 2818-2824.
[19] Sokka, S.D., King, R. and Hynynen, K. (2003) MRI-Guided Gas Bubble Enhanced Ultrasound Heating in in Vivo Rabbit Thigh. Physics in Medicine and Biology, 48, 223-241.
[20] Shankar, H. and Pagel, P.S. (2011) Potential Adverse Ultrasound-Related Biological Effects: A Critical Review. Anesthesiology, 115, 1109-1124.
[21] Duck, F.A. (2008) Hazards, Risks and Safety of Diagnostic Ultrasound. Medical Engineering and Physics, 30, 1338-1348.
[22] O’Brien Jr., W.D. (2007) Ultrasound-Biophysics Mechanisms. Progress in Biophysics and Molecular Biology, 93, 212-255.
[23] Abdelmoneim, S.S., Bernier, M., Scott, C.G., Dhoble, A., Ness, S.A.C., Hagen, M.E., et al. (2009) Safety of Contrast Agent Use during Stress Echocardiography: A 4-Year Experience from a Single-Center Cohort Study of 26, 774 Patients. JACC Cardiovascular Imaging, 2, 1048-1056.
[24] McDannold, N., Tempany, C.M., Fennessy, F.M., So, M.J., Rybicki, F.J., Stewart, E.A., et al. (2006) Uterine Leiomyomas: MR Imaging-Based Thermometry and Thermal Dosimetry during Focused Ultrasound Thermal Ablation. Radiology, 240, 263-272.
[25] Lipsman, N., Schwartz, M.L., Huang, Y., Lee, L., Sankar, T., Chapman, M., et al. (2013) MR-Guided Focused Ultrasound Thalamotomy for Essential Tremor: A Proof-of-Concept Study. Lancet Neurology, 12, 462-468.

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