Doppler velocity ratio measurements evaluated in a phantom model of multiple arterial disease
| Autor: | Louis-Gilles Durand, Louis Allard, Guy Cloutier |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
medicine.medical_specialty
Materials science Acoustics and Ultrasonics Correlation coefficient Biophysics Arterial Occlusive Diseases Concentric Sensitivity and Specificity Imaging phantom symbols.namesake medicine Humans Radiology Nuclear Medicine and imaging Ultrasonography Doppler Color Blood Volume Models Statistical Radiological and Ultrasound Technology Arterial stenosis business.industry Ultrasound Blood flow medicine.disease Models Structural Stenosis Regional Blood Flow Ultrasonography Doppler Pulsed Hemorheology Linear Models symbols Radiology business Doppler effect Algorithms Blood Flow Velocity Biomedical engineering |
| Zdroj: | Ultrasound in Medicine & Biology. 21:471-480 |
| ISSN: | 0301-5629 |
| DOI: | 10.1016/0301-5629(94)00132-w |
| Popis: | The objective of this study was to evaluate in vitro the accuracy of the Doppler velocity ratio (VR) (intrastenotic velocity/prestenotic or poststenotic velocity) under different geometric conditions simulating the presence of multiple stenoses. A steady flow loop model was used to test the influence of the presence of a concentric obstruction of 84% area reduction positioned at a distance of 10, 20 and 30 tube diameters, either proximal or distal to the stenosis under study. The stenosis under evaluation was either concentric or eccentric and had a percentage of area reduction ranging from 20% to 91%. An ultrasound color Doppler system was used to perform both pulsed-wave (PW) Doppler and color-flow velocity measurements. VRs were computed by dividing the maximum velocity of the jet by the velocity at 6 and 10 diameters both proximal and distal to the stenosis under study. A strong correlation was obtained between VR computed using color flow and PW Doppler velocities (r = 0.99). Results indicated that using the prestenotic velocity as a reference velocity generally provided a more sensitive VR index to grade arterial stenosis than using the poststenotic velocity. From a curve fit model, the measured percentages of stenosis were calculated from the VR data and compared to the true percentages. The correlation coefficient, r, was 0.95. When the proximal and distal stenoses were at 10 diameters of the stenosis investigated, r was 0.91, while it increased to 0.98 when the distance was 20 diameters or more. Although VR is theoretically not influenced by hemodynamic factors, we demonstrated that, in practice, the presence of multiple stenoses reduced its sensitivity. Volumetric flow measurements are suggested to obviate this limitation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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