Mas preguntas para el profesor Watson

Hello professor Tim:

I have been reading in your website about the ultrasound dosage calculations, but I'm a little confused about the table that indicates the intensity required at the skin surface in order to achieve a particular intensity at depth. In this table I can observe depth of lesion (cm) and intensity required at the lesion (w/cm2). I also observe some others values ​​which I do not know how to interpret. Could you help me to understand this?

Thank you for your help

R/:

Thanks for your e mail. Not sure that I can make it clear, but will have a go . . . . . .

Essentially, ultrasound will get ‘weaker’ as it penetrates into the tissues, such that at say 1cm below the surface you will have lost XX% of the energy that you have set the machine to deliver

When using the dose calcs, the ultrasound intensity (W cm-2) on the decision making chart is the intensity of the US that will need to reach the target tissue. If your intended target is not immediately under the skin, you will therefore have to account for the fact that the ultrasound gets weaker the further away (deeper) it is

By way of an example : if you want to target an ultrasound treatment to the body of the Achilles tendon, and say that in your patient (this will clearly be different for each patient), you estimate that your target tissue is 1cm below the surface, and say that you want to deliver 0,5W cm-2 to that target

Using 3MHz ultrasound (which is effective down to 2cm or so), looking at the table, go to the depth you need (across the topy on the web page chart) till you get to 1cm (the depth you are interested in) and look down the left side till you get to 0.5 W cm-2 (these are the two things that you want – how much ultrasound at what depth). Where the two lines join, it says 0.7 W cm-2 and therefore you will have to set your machine at 0,7 W cm-2 in order to get enough ultrasound (0.5W cm-2) at the depth that you intend (1cm)

If you do not do this, you will effectively UNDERDOSE – which is not dangerous, but effectively means that your treatment will not be as effective as it could be (it is not optimal)

There is a different table for the 3 and the 1MHz ultrasound as they are absorbed at different rates in the tissues

Not sure if that clears it up or not???

Regards 

Tim

Hello professor Tim:

I wonder if electrostimulation equipment used for aesthetic treatments have the same type of currents used in physical therapy. Are they effective in producing muscle contraction and strengthen the muscles? or are just commercial products. Could use such equipment to treat a patient?

Thank you very much for your help to clarify this question.

Ana Maria

R/:

Ana Maria

I am no expert in terms of aesthetic use of electrotherapy, though I have just started doing some work for a cosmetics group and therefore and learning fast . . .

 The treatments are based on the same technology - an electric current is an electric current at the end of the day - though the reasons and arguments that they use are 'alien' to a therapy discussion (all about rejuvenating collagen, skin hydration, removing cellulite etc.

 Some of the treatments are indeed very similar - muscle stim for example, but some are apparently of a completely different style (like electrolipolysis - using an electric current to 'remove' fat.

 I have not go far enough with my research to actually be able to answer your question I am afraid, though I may well end up putting some summary info on the web pages when I get there. I suspect that there will be an outcry from some of the more traditional therapists who use electrotherapy as they will feel that it is a corruption of the treatment - but you can't keep all the people happy all the time I reckon!

 Anyway, none of that is really a lot of help to you I am afraid, but if I find anything useful and decide not to put it on the web, I will try and remember to e mail you.

 Regards

 Tim