Comparison of skin surface temperatures after ultrasounds with use of paraffin oil and ultrasounds with use of gel Barbara Ratajczak • Ewa Boerner • Aneta Demidas ´ • Kinga Tomczyk • Agnieszka De ˛biec-Ba ˛k • Arletta Hawrylak Received: 23 October 2010 / Accepted: 30 May 2011 / Published online: 17 June 2011 Ó Akade ´miai Kiado ´, Budapest, Hungary 2011 Abstract Ultrasound heat effects are relatively easily perceived, being manifested by a tissue temperature rise resulting from intratissular conversion of mechanical energy into thermal one. The goal of the study reported was an evaluation of skin surface temperature distribution changes as a result of ultrasound therapy applied, with reference to the coupling medium used. The study involved 40 healthy students, with the mean age of the subjects in the study group being 20 years. All of the subjects were submitted to sonographic procedures with the use of two different coupling media, whilst skin surface temperature at the site was recorded by a thermovision camera. Sono- graphic beams were applied to the region of the left quadriceps femoris muscle by a dynamic method, using a continuous ultrasound wave of 0.5 W/cm 2 intensity and 1 MHz frequency. The area treated amounted to 300 cm 2 , the sonotherapy lasted 10 min. Paraffin oil enhanced the thermal effects of the ultrasound signals applied, inducing mean tissue temperature rises. The mean temperature recorded immediately after ultrasound application was higher than the mean base temperature by 0.33 °C, rising to 0.62 °C at the 15th minute following the procedure, with P \ 0.05. In contrast, application of gel led to considerable reductions in the mean temperatures of tissues submitted to ultrasound treatment: immediately after the sonographic procedure, tissue temperature decreased by 3.96 °C. On the basis of the results of the study conducted, it was concluded that the type of coupling medium applied influenced tem- perature levels within the treated area. Keywords Sonotherapy Á Thermovision Á Paraffin oil Á Ultrasound gel1 Introduction Physical medicine employs a number of physical factors for therapeutic, prophylactic and diagnostic purposes, including, amongst others, thermal, photochemical, elec- trokinetic and mechanical factors. Depending on the amount of energy applied, different reaction levels are induced in tissues. In recent years, the interest of researchers has increasingly been focused on the role of ultrasound in the human environment, with regard to both physical therapeutics and medical diagnostics [1]. Ultra- sound (UD) is defined as mechanical vibrations of an elastic medium with a frequency of above 16 kHz. The most commonly applied frequency in sonotherapy varies from 800 kHz to 5 MHz [2, 3]. The mechanism by which a longitudinal ultrasound wave induces a biological effect is a complex and multi- lateral process, with various physical phenomena at its base. The thermal, mechanical and physicochemical actions of ultrasound induce a number of local controlling phenomena directly in front of the US probe, resulting in pain alleviation, enhancement of reconstructive processes and normalisation of immunological reactions. These phenomena occur as a result of improved blood flow and oxygenation in tissues, accelerated functioning of pros- thetic enzyme groups, secretion of mediators and increased permeability of cellular and intracellular membranes [2]. The thermal effects of the ultrasound result from the B. Ratajczak Á E. Boerner Á A. Demidas ´(&) Á K. Tomczyk Á A. De ˛biec-Ba ˛k Á A. Hawrylak Faculty of Physiotherapy, University School of Physical Education, al. I.J. Paderewskiego 35, 51-612 Wroclaw, Poland e-mail: aneta.demidas@awf.wroc.pl 123 J Therm Anal Calorim (2012) 109:387–393 DOI 10.1007/s10973-011-1716-1