Re: Physics of Ultrasound
From: Wolfgang Moroder, MD (womorode@tin.it)
Tue Oct 30 01:00:58 2001
Dear Udayakumar
If more of us are becoming aware of such a phenomenon I am very glad I
posted my observation on this board. Next month I will be equipped with
a new vaginal probe with 10 MHz and I will try it with first trimester
examinations where we have three distinct fluids (amniotic, coelomatic
and vitelline) in three different cavities to look at.
Ciao
Wolfgang
At Tue, 30 Oct 2001, udaya kumar wrote:
>
>Dear Wolfgang,
>I see such movement quiet regularly since I use 11 Mhz for scrotal studies.
>Hydroceles have demonstrated this movement.
>..Udayakumar, Genesis Scans , INDIA.
>
>James S Smeltzer MD wrote:
>
>> A reflection of the sound wave transfers energy to the particle in question
>> as well. As the sound is kinetic energy, this should also be kinetic
>> energy. The velocity imparted would be related to the ultrasound power (at
>> the site, not the probe head), the transferrence of energy - related to the
>> echogenicity or change of acoustical impedence, the viscosity of the fluid
>> and the particle size. These may be potentially useful in determining the
>> nature of the cyst, but I am not aware of anyone who has studied this.
>> There may be too many unknowns.
>>
>> A simple study identifying how the velocity changes with changes in
>> acoustical power, the sieve results vs velocity (size may cancel out - as
>> the large and small seem to be similar in velocity - so streaming of the
>> fluid is possible, which could also have a thermal origin).
>>
>> Interesting idea, though.
>>
>> Let us know how it turns out.
>>
>> Jim Smeltzer
>>
>> At 02:01 AM 10/2/2001 -0500, you wrote:
>> >Scanning a 9 cm large pelvic cyst with a diffuse fine moderatly
>> >echogenic content (endometriosis?) I observed, for the first time, a
>> >phenomenon of the small particles moving constantly away from the 7 MHz
>> >TV probe. I could even measure the speed impressed which was aroud 0.3
>> >cm/s. With color it was more evident with a "blush" showing that the
>> >particles were accelerated by the approach of the probe. Now, my
>> >question is if it is the heat or the mechanical action of the ultrasound
>> >which impresses the movement to the particles? What kind of content
>> >(particles) could show such a phenomenon and finally if this could have
>> >some diagnostic value for the nature ot the cyst?
>> >
>> >--
>> >Wolfgang Moroder, MD
>> >Prenatal Unit
>> >Bolzano General Hospital Italy
>> >
--
Wolfgang Moroder, MD
Prenatal Unit
Bolzano General Hospital Italy
