Ultrasound is most commonly used as a visualization tool in the medical field. An ultrasound scan, also known as sonography, creates images with the reflected high frequency sound waves. These images provide useful information for diagnostics, surgery, and pregnancy. Sonography has been a staple of medical practice for nearly a century; however, recent findings suggest ultrasound could play an even more vital role in future treatments. In these studies we see how ultrasound can be used to manipulate cell proliferation, drug uptake, and other processes.
The cellular effects of ultrasound can be described as either thermal or mechanical. Acoustic energy absorbed by the cell is converted to heat although this effect is not significant utilizing low-intensity diagnostic ultrasound ( which is frequently used today). High-intensity focused ultrasound irradiation has been shown to induce cancer cell death or aid in drug uptake through temperature dependent systems [1]. Pressure and vibration from the ultrasound stimulation are responsible for changes to cell membrane tension and cavitation through sonoporation which allows better diffusion of treatment through the cell membrane.
Studies on cellular effects of ultrasound are primarily conducted in-vitro using an immersion transducer and cultured cells. The transducer emits an ultrasound laser directly into the cell plate where the effects are observed [2]. Clinical trials are being conducted using ultrasound to successfully treat port-wine stains in skin [3]. In vivo experiments are mainly non-invasive simply beaming the ultrasound through the skin and have found to have various beneficial effects such as inhibiting tumor growth [4], promoting wound healing and healthy cell proliferation, increasing cell membrane permeability for treatments, and more [5, 6]. Researchers aim to target specific cellular mechanisms using various parameters of the ultrasound in order to precisely administer therapy.
Written By: Mathew Loren
Keywords: ultrasound, sonoporation, sonography
References
Tian, Yuhang et al., New Aspects of Ultrasound-Mediated Targeted Delivery and Therapy for Cancer, Int J of Nanomedicine 2020; 15:401-418, doi: 10.2147/IJN.S201208
Katiyar, Amit et al., Inhibition of Human Breast Cancer Cell Proliferation by Low-Intensity Ultrasound Stimulation, J Ultrasound in Medicine 2020; 39(10); 2043-2052, doi: 10.1002/jum.15312
Troilius, A et al., Ultrasound investigation of port wine stains, Acta Derm Venereol 2000, 80(3):196-9, doi: 10.1080/000155500750042961
Ma, C-M et al., An in-vivo investigation of the therapeutic effect of pulsed focused ultrasound on tumor growth, Med Phys 2014; 41(12);122901, doi:10.1118/1.4901352
Wood, Andrew K. et al., A Review of low-intensity ultrasound for cancer therapy, Ultrasound Med Biol. 2015 April, 41(4):905-928, doi: 0.1016/j.ultrasmedbio.2014.11.019
Huang, Chenyu et al., Mechanobiology and Mechanotherapy for Cutaneous Wound Healing, Mechanobiology:239-253, doi: 10.1002/9781118966174.ch15