As. Anayiotos et al., AN IMPROVED FLOW EVALUATION SCHEME IN ORIFICES OF DIFFERENT ASPECT RATIOS, Ultrasound in medicine & biology, 23(2), 1997, pp. 231-244
Citations number
21
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging",Acoustics
An accurate and reliable method of regurgitant flow calculation is cur
rently unavailable, The goal of this study was to define a new general
method of flow calculation for orifices of different aspect ratios, T
he success of the method relies on matching the imaged flow field dist
ribution obtained by color flow mapping (CFM) to a three-dimensional (
3D) numerical how field distribution of known geometry, The flow field
in three orifices of identical cross-sectional area with aspect ratio
s of 1 (circular), 2 and 4 (elliptical) was evaluated by: (a) CFM, (b)
3D echocardiographic imaging, and (c) 3D finite element modeling (FEM
), The orifice shape and size were accurately estimated by 3D echocard
iographic imaging, FEM showed that the normalized centerline velocity
profile of the flow field depends on the orifice aspect ratio, CFM pro
vided a good description of the centerline profile for each case, For
a given distance from the orifice center, the equivelocity contour sur
face area increases with increasing aspect ratio, A simple flow calcul
ation scheme was developed to calculate regurgitant flow independent o
f orifice shape, This improved method showed better results than previ
ous studies and may prove to be advantageous when analyzing in vivo fl
ow fields with complex geometries. (C) 1997 World Federation for Ultra
sound in Medicine & Biology.