Low-Intensity Continuous Ultrasound Therapies—A Systematic Review of Current State-of-the-Art and Future Perspectives

Abstract

Therapeutic ultrasound has been studied for over seven decades for different medical applications. The versatility of ultrasound applications are highly dependent on the frequency, intensity, duration, duty cycle, power, wavelength, and form. In this review article, we will focus on low-intensity continuous ultrasound (LICUS). LICUS has been well-studied for numerous clinical disorders, including tissue regeneration, pain management, neuromodulation, thrombosis, and cancer treatment. PubMed and Google Scholar databases were used to conduct a comprehensive review of all research studying the application of LICUS in pre-clinical and clinical studies. The review includes articles that specify intensity and duty cycle (continuous). Any studies that did not identify these parameters or used high-intensity and pulsed ultrasound were not included in the review. The literature review shows the vast implication of LICUS in many medical fields at the pre-clinical and clinical levels. Its applications depend on variables such as frequency, intensity, duration, and type of medical disorder. Overall, these studies show that LICUS has significant promise, but conflicting data remain regarding the parameters used, and further studies are required to fully realize the potential benefits of LICUS.

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Sustained acoustic medicine for the treatment of musculoskeletal injuries: a systematic review and meta-analysis

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“…This limitation was beyond the scope of this research but could be considered in a future analysis paying close attention to time, duration, dose delivered and regularity of ultrasound treatment. The literature search strategy we employed found 13 relevant articles specific to SAM that are more than other past reviews on Sustained Acoustic Medicine ever, it is possible that some relevant studies were missed that were not available in English language or those in the grey literature which are emerging on this new therapeutic treatment [ 79 , 92 , 93 ]. Additionally, several of the outcome variables used in the studies differed in both measure, physical location on the body, condition being treated and control group which limited the scope of meta-analysis.…”