I-Tech WEPERE RESTART, User Manual

Page: 10 / 28

USER MANUAL 10
Pack contents
The RESTART pack contains:
• 1 RESTART device;
• 1 medical power supply;
• 1 battery charger;
• 1 gel for ultrasound;
• 1 carry bag;
• 1 user manual.
Introduction to the technology
Ultrasound treatment represents a method that is based on the transfer of energy into the tissues
which results in thermal and non-thermal biological effects.
This treatment is based on the contact between the head of the device and the tissues being
treated. The optimal coupling of these two surfaces is ensured by the use of a water-based ultra-
sound gel. Through the contact described the transmission of general mechanical waves from
the piezoelectric present inside the head of the device takes place. In order for there to be maxi-
mum transmission of energy from one medium to another, the impedance of the two must be the
same. Obviously in the case of the human body, such condition hardly occurs.
The greater the impedance difference between the two media, the greater the reflection and con-
sequently the smaller the amount of energy that will be transferred. The impedance difference is
greatest with aluminium-air interface, which is the first that ultrasound waves would have to over-
come to reach the body. To reduce this difference, a coupling substance must be used. If there is a
small amount of air between the transducer and the skin, the proportion of ultrasound waves that
would be reflected would reach 99.998%, i.e. there would be no transmission.
In addition to the phenomenon of reflection, if the wave does not hit the separation surface
between the media at 90°, refraction occurs. In practice, the direction of the ultrasound beam
through the second medium will be angled. The critical angle for ultrasound waves at the skin
surface appears to be 15°.If the device head is oriented at a 15° angle to the surface, most of the
beam will propagate through the epidermal tissues parallel to the skin rather than perpendicular
to the tissues.
The absorption of the energy released by the ultrasound waves follows an exponential trend, in
fact much more energy is absorbed in superficial tissues rather than in deep ones.
Precisely due to the trend of absorption, theoretically there is no point where all the energy is absor-
bed, but there is certainly a point where these levels are not sufficient to produce a therapeutic effect.
Generally tissues with the highest protein content will absorb more, unlike tissues with high water
and low protein content, which will absorb a minimal amount of energy (blood and fat, for example).