Context The effect of ultrasound frequency on phonophoresis drug delivery in humans is unknown. Objective To determine if a low (45-kHz) or high (1-MHz) frequency delivered a higher dexamethasone (Dex) concentration through the skin. Design Controlled laboratory study. Setting Laboratory. Patients or Other Participants A total of 40 healthy men between the ages of 18 and 45 years (age = 23.1 ± 2.6 years, height = 176.1 ± 7.2 cm, mass = 88.5 ± 19.4 kg, posterior calf subcutaneous thickness measured using musculoskeletal ultrasound imaging = 0.6 ± 0.2 cm). Intervention(s) Participants were randomly assigned to 1 of 4 groups (ultrasound frequency at microdialysis probe depth): (1) 45-kHz frequency at 1 mm, (2) 45-kHz frequency at 4 mm, (3) 1-MHz frequency at 1 mm, or (4) 1-MHz frequency at 4 mm (n = 10 in each group). Three linear microdialysis probes were inserted at the desired tissue depth. We rubbed dexamethasone sodium phosphate (Dex-P) into the skin and then applied a 15-minute phonophoresis treatment. Main Outcome Measure(s) Dialysate was collected during the treatment and 60 minutes posttreatment and analyzed for Dex-P, Dex, and the metabolite form of Dex. The sum of the 3 analytes was calculated as total dexamethasone (Dex-total), and differences between the 45-kHz and 1-MHz treatment groups were determined by a repeated-measures analysis of variance. Results At 1 mm, 3 (30%) participants in the 45-kHz and 4 (40%) participants in the 1-MHz group had measurable levels of Dex-P. Total dexamethasone increased after the treatment ceased, independent of ultrasound frequency (P &amp;lt; .001), with a trend of the 45-kHz treatment to produce a greater increase in drug concentration (P = .006). At 4 mm, 5 (50%) participants in the 45-kHz and 1 (10%) participant in the 1-MHz group had measurable levels of Dex-P. We observed no difference in Dex-total concentration between treatment groups at 4 mm (P = .72). Conclusions Phonophoresis provided a mechanism for Dex-total delivery at the 1- and 4-mm tissue depths. However, the effectiveness of the ultrasound frequencies varied between the 2 measured tissue depths.

Justin H. Rigby

Austin M. Hagan

Austin R. Kelcher

Chang Ji

Journal of Athletic Training

运动训练杂志的使命是通过在预防、评估、管理和康复损伤方面的教育和研究，加强对体育活动者的医疗保健质量感兴趣的专业人士之间的交流。运动训练杂志提供您可以使用的研究在日常实践中。它让您了解最终定义专业护理标准的科学进步——如果您对患者的福祉负责，您就不能没有这一点。

The mission of the Journal of Athletic Training is to enhance communication among professionals interested in the quality of healthcare for athletes through education and research in the prevention, assessment, management, and rehabilitation of injuries. The journal provides research that you can apply in daily practice, keeping you informed about the scientific advancements that ultimately define the standards of professional care. If you are responsible for the well-being of your patients, you cannot do without this information.

《Journal of Athletic Training》的使命是通过在预防、评估、管理和康复损伤方面的教育和研究，增强对体育活动者医疗保健质量感兴趣的专业人士之间的交流。该杂志提供可在日常实践中使用的研究成果，让您了解定义专业护理标准的科学进展。如果您对患者的福祉负责，这些信息是必不可少的。

Dexamethasone Sodium Phosphate Penetration During Phonophoresis at 2 Ultrasound Frequencies

Phonophoresis provided a mechanism for Dex-total delivery at the 1- and 4-mm tissue depths, however, the effectiveness of the ultrasound frequencies varied between the 2 measured tissue depths.

Category	Quartile
医学	2
医学, 运动科学	3

Dexamethasone Sodium Phosphate Penetration During Phonophoresis at 2 Ultrasound Frequencies

ivySCI AI Smartly Parses PDF, Answers Researchers' Questions, and Helps You Understand Papers in Seconds

Journal Info

Category	Quartile
SPORT SCIENCES	1