Quantitative study of flow dependence in NMR images at low flow velocities
Ståhlberg, Freddy LU ; Nordell, Bo ; Ericsson, Anders ; Greitz, Torgny ; Persson, Bertil LU
and Sperber, Göran
(1986)
In Journal of Computer Assisted Tomography
10(6).
p.1006-1015
- Abstract
A basic theoretical model that describes the effects of flow in and out of the imaging plane in nuclear magnetic resonance (NMR) images, obtained with the standard pulse sequences single spin echo, multiple spin echo, and inversion recovery, is presented. Theoretically calculated signal values are compared with experimental results obtained from single-slice images of a flow phantom for variable flow velocity v as well as for variable echo time and inversion time at flow velocities <10 mm/s, corresponding to those found in cerebrospinal fluid, in capillary systems, and in smaller veins. The quantitative correspondence between theory and experiment is good in the range of velocities studied and for the imaging parameters used, but... (More)
A basic theoretical model that describes the effects of flow in and out of the imaging plane in nuclear magnetic resonance (NMR) images, obtained with the standard pulse sequences single spin echo, multiple spin echo, and inversion recovery, is presented. Theoretically calculated signal values are compared with experimental results obtained from single-slice images of a flow phantom for variable flow velocity v as well as for variable echo time and inversion time at flow velocities <10 mm/s, corresponding to those found in cerebrospinal fluid, in capillary systems, and in smaller veins. The quantitative correspondence between theory and experiment is good in the range of velocities studied and for the imaging parameters used, but discrepancies occur when higher velocities are studied. In addition, flow in a capillary model is demonstrated qualitatively for very low linear flow velocities, <1 mm/s. It is concluded that the model describes the essentials of the inflow-outflow effect and that this effect can predict the flow dependence of the NMR signal for low flow velocities. Observed differences between model and experiment may be due to effects of flow-induced phase alterations and due to uncertainty in measurements of the relaxation times T1 and T2. The model described here can be extended to suit other types of pulse sequences and to suit multislice imaging. It can also be extended to incorporate flow-induced phase effects.
(Less)
- author
- Ståhlberg, Freddy
LU
; Nordell, Bo
; Ericsson, Anders
; Greitz, Torgny
; Persson, Bertil
LU
and Sperber, Göran
- organization
- publishing date
- 1986-01-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Blood flow, Magnetic resonance imaging, physics and instrumentation, Magnetic resonance imaging, techniques
- in
- Journal of Computer Assisted Tomography
- volume
- 10
- issue
- 6
- pages
- 10 pages
- publisher
- Lippincott Williams & Wilkins
- external identifiers
-
- pmid:3782539
- scopus:0022993572
- ISSN
- 0363-8715
- DOI
- 10.1097/00004728-198611000-00022
- language
- English
- LU publication?
- yes
- id
- fa1a9b22-40b0-40de-9f43-1b8bb3b1cdbb
- date added to LUP
- 2020-05-07 21:17:15
- date last changed
- 2024-01-02 10:34:50
@article{fa1a9b22-40b0-40de-9f43-1b8bb3b1cdbb,
abstract = {{<p>A basic theoretical model that describes the effects of flow in and out of the imaging plane in nuclear magnetic resonance (NMR) images, obtained with the standard pulse sequences single spin echo, multiple spin echo, and inversion recovery, is presented. Theoretically calculated signal values are compared with experimental results obtained from single-slice images of a flow phantom for variable flow velocity v as well as for variable echo time and inversion time at flow velocities <10 mm/s, corresponding to those found in cerebrospinal fluid, in capillary systems, and in smaller veins. The quantitative correspondence between theory and experiment is good in the range of velocities studied and for the imaging parameters used, but discrepancies occur when higher velocities are studied. In addition, flow in a capillary model is demonstrated qualitatively for very low linear flow velocities, <1 mm/s. It is concluded that the model describes the essentials of the inflow-outflow effect and that this effect can predict the flow dependence of the NMR signal for low flow velocities. Observed differences between model and experiment may be due to effects of flow-induced phase alterations and due to uncertainty in measurements of the relaxation times T1 and T2. The model described here can be extended to suit other types of pulse sequences and to suit multislice imaging. It can also be extended to incorporate flow-induced phase effects.</p>}},
author = {{Ståhlberg, Freddy and Nordell, Bo and Ericsson, Anders and Greitz, Torgny and Persson, Bertil and Sperber, Göran}},
issn = {{0363-8715}},
keywords = {{Blood flow; Magnetic resonance imaging, physics and instrumentation; Magnetic resonance imaging, techniques}},
language = {{eng}},
month = {{01}},
number = {{6}},
pages = {{1006--1015}},
publisher = {{Lippincott Williams & Wilkins}},
series = {{Journal of Computer Assisted Tomography}},
title = {{Quantitative study of flow dependence in NMR images at low flow velocities}},
url = {{http://dx.doi.org/10.1097/00004728-198611000-00022}},
doi = {{10.1097/00004728-198611000-00022}},
volume = {{10}},
year = {{1986}},
}