Learning objectives
To describe the most common artefacts in prostate US elastography.
To suggest how to interpret them,
for improving the operator’s diagnostic confidence.
Ultrasound (US) elastography is a novel imaging technique which was purposed as to be able to map tissue stiffness in various organs [1-5].
Elastography measures tissue stiffness looking at modifications of the US image after applying mechanical stress [6].
Two real-time elastography methods have been proposed for the prostate tissue elasticity analysis: strain elastography (SE) [7] and shear wave elastography (SWE) [8].
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Background
Image artefacts are common in US imaging.
In prostate ultrasound elastography most of them are generated by the physical limitations and cannot be avoided; some others,
related to the organ and transducer geometry or the examination technique can be overcome by a proper technique.
Some artefacts are strictly related to the algorithms used by the different systems.
These artefacts will be described to accurately distinguish them,
leading the operators to improve their diagnostic level.
Findings and procedure details
MATERIALS
Our collection of artefacts in prostatic elastography was carried out using various systems equipped with different elastography algorithms for SE (Resona 7,Mindray,
China; MyLab Twice HD and MyLab 8,
Esaote,
Italy; Hi-Vision EUB 8500 and Preirus,
Hitachi Medical System,
Japan; Logiq E9,
GE Healthcare,
USA).
For SWE only one system was available on the market until recently (Aixplorer,
SuperSonic Imagine,
France).
TRANSDUCER CHOICE
Although bi-convex and linear transducers are available,
the end-fire convex transducer is generally preferred for SE; prostatic SWE is currently supported...
Conclusion
Elastography is a low-cost and non-invasive technique,
easy to use after proper training and without any additional discomfort to the patient,
compared to standard TRUS.
It is essential for any operator to be aware of,
and able to recognise US elastography artefacts,
thus improving the diagnostic accuracy.
Personal information
Alfredo Goddi
SME Medical Center - Diagnostic Imaging,
Varese,
Italy
Lisa Milan
Medical Physics Department,
ASST dei Sette Laghi,
Varese,
Italy
Paola Nocera
Medical Physics Department,
ASST dei Sette Laghi,
Varese,
Italy
Raffaele Novario
Department of Biotechnology and Life Sciences,
University of Insubria,
Varese,
Italy.
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