| Influence of pulse repetition frequency and high pass filter on color Doppler maps of converging flow in vitro. | |
| | |
MedLine Citation:
|
PMID: 8993988 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Assessment of regurgitant flow by the flow convergence method is based on reading absolute velocities from color Doppler maps. Velocity overestimation by high pass filtering above 100 Hz has been reported. An extremely low filter, however, is impracticable in patients. A ratio of pulse repetition frequency (PRF)/filter of 10/1 usually results in good quality color maps as judged visually. We studied in vitro the influence of RPF and filter on the absolute velocities within color maps of the flow convergence, keeping PRF/filter at 10/1. The color maps were also compared with computerized flow simulations. Flow across different orifice plates was scanned using two different setups for each flow condition: low velocity setup (PRF 600-2500 Hz, filter 50-300 Hz) and high (PRF 1500-6000 Hz, filter 200-600 Hz). From the color maps, velocity profile curves were read along the flow center line across the flow convergence. The high velocity setup provided artefact-free color maps at a distance d = 2-4 through 8-11 mm to the orifice, the low setup at d = 6-8 through 18 mm. Within the overlapping range (d = 6-8 through 8-11 mm), the resulting curves showed no significant differences in local velocity, with a slight trend towards higher velocities with the high velocity setup (2.2-2.9%). The simulations agreed well with color Doppler except for slightly lower values at d > 10-12 mm. Changes in PRF and filter have no significant influence on the absolute velocities displayed within color maps as long as PRF/filter is kept close to 10/1. |
| | |
Authors:
|
M Giesler; V Göller; A Pfob; D Bajtay; M Kochs; V Hombach; G Grossmann |
Related Documents
:
|
8889698 - Effects of endothelin-1 on the rat testicular vasculature. 16307338 - Sperm recovery prediction in azoospermic patients using doppler ultrasonography. 11578358 - Prediction of malignancy using transvaginal color flow doppler in patients with gynecol... 8246338 - Posttraumatic "high-flow" priapism evaluation with color flow doppler sonography. 10921698 - Tissue engineering of heart valves: in vitro experiences. 14992738 - Use of an oxygen therapeutic as an adjunct to intraoperative autologous donation to red... |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: International journal of cardiac imaging Volume: 12 ISSN: 0167-9899 ISO Abbreviation: Int J Card Imaging Publication Date: 1996 Dec |
Date Detail:
|
Created Date: 1997-03-26 Completed Date: 1997-03-26 Revised Date: 2000-12-18 |
Medline Journal Info:
|
Nlm Unique ID: 8600426 Medline TA: Int J Card Imaging Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 257-61 Citation Subset: IM |
Affiliation:
|
Department of Internal Medicine II, Cardiology, Angiology, Pneumonology and Nephrology, Ulm University, Germany. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Blood Flow Velocity Echocardiography, Doppler, Color* Phantoms, Imaging Rheology* |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Provocation of left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopat...
Next Document: On-site digital quantitative coronary angiography: comparison with visual readings in interventional...