Challenges in contrast-enhanced spectral mammography interpretation: artefacts lexicon

• Image artifacts are common on CESM studies.
• CESM artifacts include rim, ripple, axillary line and skin-line artifact.
• Identifying artifacts is crucial for not misinterpreting them as breast pathology.
• Once recognized correctly, artifacts in CESM do not hamper image interpretation.

AimTo review and describe commonly encountered artefacts in contrast-enhanced spectral mammography (CESM).Materials & methodsThis retrospective study included 200 women who underwent CESM examinations for screening and diagnostic purposes. Analysis was performed on the image data sets of these women, comprising of a total of 774 subtracted images. Images were reviewed with focus on the presence of four artefacts: rim (“breast within breast”), ripple (black and white lines), axillary line, and skin-line enhancement (skin-line highlighting). Statistical cross-correlation and association with acquisition parameters (tube current, tube voltage, compression force, breast thickness, paddle size) was compared using Fisher's exact test and t-test.ResultsThe rim artefact was highly common (97–99%) in every projection. The ripple artefact was increasingly more common on the oblique projections (80–82%) and found to be associated with higher breast thickness values. The axillary line artefact was detected only on oblique projections (63%) and associated with the use of a small compression paddle. The skin-line enhancement artefact was seen in 19–46% of projections. None of the artefacts interfered with image interpretation.ConclusionsTwo main artefacts commonly seen on CESM are rim and ripple artefacts. They do not hamper with image interpretation. It is important to be aware of them and prevent misinterpretation of these artefacts as real breast pathology.