Learning objectives
The goal of our work is to classify,
explain the genesis and provide countermeasures to artifacts that may be generated in MRI exam.
Background
An artifact in MRI is configured as a result of distortion / alteration of the image that causes an image representation that does not correspond to reality.It is a finding inside the images not normally anatomically present,
but visible due to limitation / malfunction in hardware / software,
extrinsic (heat or humidity environment) or intrinsic (pulsation,
breathing,
implants) factors.
The knowledge of the artifacts and the factors that produce noise is important to obtain high quality images.
From this the idea to classify,
describe and...
Findings and procedure details
We describe case-by-case from technical reason to countermeasures,
evaluating them on both low magnetic field (Esaote,
O-Scan) and 1.5 T magnet (Philips D-Stream).
Chemical shift (CS) artifact can be divided into type I and II.
Type I is found along the direction of frequency encoding,
only in the presence of magnetic fields (B0) > 1T.
Type II is found in any of the field intensity,
especially in Gradient Echo (GE) sequences with particular echo times.
The alteration appears as a black band or white at...
Conclusion
It’s necessary to understand the source of the artifact: some artifacts can be fixed only by adjusting the parameters directly into the MRI Client workstation (typical solution for the physical-chemical artifacts); others are solved using specific equipment (eg.
cardiac or respiratory gating,
bolus tracking); for others (hardware and software) the only possible solution is to request technical assistance.
Personal information
A.
Cassarà,
Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
G.
Fini,Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
T.
Bongiovanni,Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
F.
Cartabbia,Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
E.
Soligo,
Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
M.
Abruzzese,Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
L.
Y.
Samman,Department of Diagnostic Imaging,
AOU Maggiore della Carità,
Novara,
ITALY
A.
Stecco,Department of Diagnostic Imaging,...
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Smith RC,
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Chemical shift artifact:...