Learning objectives
The purpose of this exhibit is to illustrate the basic physics and the genesis of artifacts in breast tomosynthesis.
The content is organized under
- Principle
- Genesis of artifacts- why they occur
- Artifacts due to acquisition
- Artifacts due to reconstruction
- Altering image parameters- can we avoid artifacts ?
- 5 points to remember while interpreting tomosynthesis
Background
Digital Breast Tomosynthesis is an exciting new technology that holds promise in improving cancer detection by removal of overlap of tissue in mammography[1,2,3,4].
The technology represents a compromise between obtaining a 3rd dimension and minimizing radiation exposure to the exquisitely radiation-sensitive organ.
It is thus,
prone to a number of artifacts.
Principle
The basic principle of tomosynthesis is similar to stereovision- the mechanism by which the human brain perceives the depth of an object by comparing images formed by the two eyes(fig 1).
Unlike in...
Imaging findings OR Procedure details
ARTIFACTS DUE TO ACQUISITION
These artifacts are primarily truncation artifacts due to the limited size of the detector and of the x-ray beam.
a) Bright area artifact- where the detector cant see [6]
WHY DOES IT HAPPEN ?
The area marked (a)attenuates the beam when the tube is in position(A) and is projected to area (a')on the detector.
The detector however is unaware of the presence of breast tissue in the marked area.
The attenuation caused by this area is added to the mostperipheral part...
Conclusion
CONCLUSION
Tomosynthesis is a modality intrinsically prone to artifacts due to limited sampling of tissue
Artifacts are thus here to stay in DBT in its present avatar,
thus their awareness,
and identification is the key to correct interpretation
5 POINTS TO REMEMBER WHILE INTERPRETING TOMOSYNTHESIS
Reduction of artifacts represent a trade-off between depth resolution,
in-plane resolution and radiation exposure
The various artifacts are summarized below for a quick recapitulation
Bright area
Fig. 4
Bright areas at the edges of tissue due to attenuation by tissue...
References
VecchioS ,
Albanese A,
Vignoli P et al.A novel approach to digital breast tomosynthesis for simultaneous acquisition of 2D and 3D images.
Eur Radiol 2011; 21:1207 –1213
Poplac k SP,
Tosteson TD,
Kogel CA,
Nagy HM.
Digital
breast tomosynthesis : initial experience in 98 women with abnormal digital screening mammography.
Am J Roentgenol
2007;189:616– 623
Andersson I,
I ked a DM,
Zackrisson S ,
R uschin M,
Svahn T,
Timberg P,
Timberg A .Breast tomosynthesis and
digital mammography: a comparison of breast cancer visibility and...
Personal Information
CONTACT DETAILS
1.
Krithika Rangarajan
Student,
Department of Radiodiagnosis
All India Institute of Medical Sciences
New Delhi
[email protected]
2.
Smriti Hari
Associate Professor
Department of Radiodiagnosis
All India Institute of Medical Sciences
New Delhi
Special thanks to Mrs Poonam Mukhi,
Radiographer,
Mammography for the valuable support