Learning objectives
To illustrate the semeiology of malignant breast lesions in Digital Breast Tomosynthesis (DBT).
We first reviewed the technical aspects of DBT and the appearance of malignant lesions according to ACR BIRADS classification [1].
Our aim was to evaluate the usefulness of classical mammography semeiology as described in literature [1,2] in Tomosynthesis images,
and to underline possible adjunctive findings suggestive for malignancy.
Background
Digital Breast Tomosynthesis is a technique that uses conventional x-rays and a digital detector to obtain a variable number of images from the acquisition of multiple low-dose projections of the breast.
The reconstructed images show a plane of the breast in sharp focus,
while tissue above and below appears out of focus [3,4].
Various vendors are undergoing clinical trials,
but up to now there is no universally accepted technology.
General characteristics of a DBT unit are:
-the presence of a moving x-ray source with an...
Imaging findings OR Procedure details
Technique
We used a digital system to obtain both mammography and tomosynthesis images (Giotto TOMO,
IMS,
Bologna,
Italy; Fig.
1).
The unit acquires 13 projections with a low dose protocol on a ±20° angular range; detector is stationary.
Other technical aspects are:
-W-target X-ray source;
-a-Se digital detector (ANRAD,
LMAM) with a sensitive area 24x30 cm2 and squared pixel pitch0.085 mm;
-Iterative reconstruction algorythm
-Reconstructed voxel size: 0.085 mm×0.085 mm×1.0 mm
Exposure parameters are determined by Automatic Exposure Control (AEC).
AEC for DBT in one...
Conclusion
Mammography semeiology already described and classified by ACR can be used also for DBT.
Tomosynthesis differs from mammography regarding:
- the better identification of lesion shape and margins,
due to the higher contrast compared to breast parenchima;
- the difficulty,
in some cases,
in defining the distribution of microcalcification,
when present on more than one slice.
References
1.
D'Orsi CJ,
Mendelson,
EB,
Ikeda DM,
et al.
Breast Imaging Reporting and Data System: ACR BI-RADS – Breast Imaging Atlas,
Reston,
VA,
AmericanCollege of Radiology 2003
2.
Obenauer S,
Hermann KP,
Grabbe E.
Applications and literature review of the BI-RADS classification Eur Radiol.
2005;15:1027–1036
3.
Baker JA,
Lo JY.
Breast Tomosynthesis: State-of-the-Art and Review of the Literature.
Acad Radiol 2011;18:1298–1310
4.
Feng SSJ,SechopoulosI.Clinical Digital Breast Tomosynthesis System: Dosimetric Characterization Radiology 2012;263(1):35-42
5.
Park JM,
Franken EA,
Garg M,
et al.
Breast Tomosynthesis: Present Considerations...
