کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
873096 910298 2011 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental validation of non-invasive and fluid density independent methods for the determination of local wave speed and arrival time of reflected wave
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی پزشکی
پیش نمایش صفحه اول مقاله
Experimental validation of non-invasive and fluid density independent methods for the determination of local wave speed and arrival time of reflected wave
چکیده انگلیسی

The relationship between the vessel diameter (D) and fluid velocity (U) in arteries and flexible tubes has been recently characterized as linear in the absence of wave reflections. This relationship allowed for determining local wave speed (CDU) using the lnDU-loop method. Using CDU, it was possible to separate U and D waveforms into their forward and backward components. It was also possible to calculate wave intensity (dIDU), using D and U, from which the arrival time of reflected wave (TrwDU) could be determined. These techniques are fluid density independent and require only non-invasive measurements of D and U.In this work we experimentally validate the relative accuracy of these new techniques in vitro, by comparing their results of CDU and TrwDU to those determined by the established techniques, PU-loop and wave intensity analysis, C and Trw, respectively. We generated a single semi-sinusoidal wave in long flexible tubes, and simultaneously measured pressure (P), D, and U at the same site. Sequentially in time, we repeated this experiment at three sites along each of the flexible tubes, which were made of different materials and sizes, and three fluids of different densities.CDU compared well with that C and likewise TrwDU was very similar to Trw. Varying fluid density did not appreciably change the difference between the results of the two techniques.We conclude that the new techniques for determining CDU and TrwDU, although independent of density, provide relatively accurate estimates of wave speed and arrival times of reflected waves in vitro. The new techniques require only non-invasive measurements of D and U, and further in vivo validation is required to establish its advantage in the clinical setting.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Biomechanics - Volume 44, Issue 7, 29 April 2011, Pages 1393–1399
نویسندگان
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