Author(s)

Monika Kakani¹, Neeraj Rathi¹, Ahdy Helmy², Ashok Kumar Thella¹, M. D. James Rizkalla³, Paul Salama¹, Maher E. Rizkalla^1,4,5

¹Department of Electrical and Computer Engineering, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, USA.
²VA Hospital, Indiana University School of Medicine, Indianapolis, USA.
³Baylor University Medical Center (BUMC), Dallas, USA.
⁴Integrated Nanosystems Development Institute, IUPUI, Indianapolis, USA.
⁵Richard G. Lugar Center for Renewable Energy, IUPUI, Indianapolis, USA.

The impact of arterial narrowing/blocking caused by plaque buildup in arteries leads to many life-threatening consequences. This is recognized as a cause in heart attacks and peripheral vascular disease. Diagnosing the illness is only feasible after symptoms have presented to the patient. Currently, the standard for visualizing coronary arteries is through angiography, which may have complications, and impact on the healthcare system. Furthermore, cardiac catheterization may also places high health risks, given its overall invasiveness. Cardiac arrhythmias, infection, and contrast dye nephrotoxicity are recognized complications within this process. Therefore, a noninvasive approach may have potentials to reduce patient complications, finances surrounding healthcare, and more efficient patient care through earlier screening and diagnosing. This research addresses a new approach using photoacoustic (PA) imaging. The transmission properties of atherosclerosis within walls of arteries, can be exploited using photo acoustics, to better visualize and characterize the degree and severity of atherosclerosis. The delivered energy is absorbed by components of the vascular tissue converted into heat, leading to transient thermos elastic expansion, which creates an acoustic emission. The thermal response was analyzed for its fall and recovery times that are attributed to the artery fat type. The control parameters, including the frequency, penetration depth, energy levels, and tissue layer sizes, for multilayered structures were considered. The structures investigated were fatty infiltrate within the artery, blood, bones, and skin, within frequency range from 1 MHz to 3 MHz, and typical tissue sizes in the milli to centimeter range. As high as 14 MPas in the acoustic pressure at 1 MHz, resulted in temperature difference of up to 3.4 K. When the operating frequency was altered to 2 MHz, the temperature changed to 23 K. Furthermore, when the frequency was changed to 3 MHz, the temperature moved to 43 K. The changes in temperatures were for nearly 1 second duration. The results obtained in this study suggest that there is high potential for practical models using flexible substrate with infra-red sensors and acoustic devices.

Acoustic, Thermal, Cardiovascular, Diagnosis, MEMS/NEMS, COMSOL, Multilayers, Non-Invasive

Kakani, M. , Rathi, N. , Helmy, A. , Thella, A. , Rizkalla, M. , Salama, P. and Rizkalla, M. (2017) Photo Acoustic Energy Applications for the Detection of Human Arterial Blockages via Multiple Skin/Bone Layers, a Non-Invasive Approach. World Journal of Cardiovascular Diseases, 7, 251-270. doi: 10.4236/wjcd.2017.78024.