Characterization of Focal Liver Masses: A Multicenter Comparison of Contrast‐Enhanced Ultrasound, Computed Tomography, and Magnetic Resonance Imaging

Abstract

Objectives-To demonstrate the usefulness of contrast-enhanced ultrasound (CEUS) for the evaluation of focal liver masses via a direct comparison to standard ultrasound and computed tomography/magnetic resonance imaging (CT/MRI).Methods-A cohort of 214 patients with previously undiagnosed focal liver masses were included from 5 different centers. Each patient was imaged using CEUS and CT and/or MRI. Anonymized and randomized images were interpreted by 4 separate blind readers from 3 of the participating centers (2 readers for CEUS and 2 readers for CT/MRI). Readers were blinded to patient demographics and past medical history. Readers were asked to decide if the lesion was benign or malignant, provide a final diagnosis for the lesion, and provide a confidence interval. Results were compared to truth standard from pathology or expert consensus.Results-In determination of malignancy, CEUS had a sensitivity of 95%, specificity of 82%, PPV of 82%, NPV of 95%, statistically better than standard ultrasound (sensitivity 82%, specificity 56%, PPV 60%, NPV 78%) with P < .01 and not statistically different from CT (sensitivity 90%, specificity 73% PPV 81%, NPV 86%) or MRI (sensitivity 85%, specificity 79%, PPV 68%, NPV 91%) with P ≥ .01. In assigning a final diagnosis, CEUS had an accuracy of 78% statistically better than standard ultrasound (46%) with P < .01 and not statistically different from CT (68%) or MRI (71%) with P > .01.Conclusions-In the evaluation of focal liver lesions, both for determination of malignancy and in accuracy of final diagnosis, CEUS performs better than standard ultrasound and at least equivalent to both CT and MRI.

Interpretable Machine Learning for Characterization of Focal Liver Lesions by Contrast-Enhanced Ultrasound

“…Moreover, in this preliminary study, we focused on short cines of about 1 min, visualizing only part of the arterial wash-out, which often overlaps with the beginning of the portal phase. As the contrast agent wash-out in the portal and late phase has shown to aid diagnosis [ 12 ], [ 51 ], [ 52 ], investigation of additional features extracted at later phases should be performed in the future. Repeated, short acquisitions (~10 s) of the wash-out at different time points, up to about 6 min, are in fact available for this dataset and could be exploited in the future.…”

Algorithm‐based approach to focal liver lesions in contrast‐enhanced ultrasound

“…'Marked' washout is used when the lesions demonstrate a 'punched-out' appearance relative to the background liver and is suggestive of non-hepatocellular malignancies, while 'mild' washout is seen when residual microbubbles are still visible within the washed out region and is suggestive of HCC. 15 Third, to make the final diagnosis, the pattern of enhancement on the PVP should be reviewed and arterial phase images revisited to pick up typical features (e.g. spoke-wheel enhancement in focal nodular hyperplasia (FNH) and discontinuous peripheral nodular enhancement in haemangioma).…”

“…ICC and metastasis), whereas ‘late’ washout occurs after 1 min and is suggestive of HCC. ‘Marked’ washout is used when the lesions demonstrate a ‘punched‐out’ appearance relative to the background liver and is suggestive of non‐hepatocellular malignancies, while ‘mild’ washout is seen when residual microbubbles are still visible within the washed out region and is suggestive of HCC 15 …”

A Novel Technology for Resolution of CEUS Imaging Problems in Patients With High BMI and Fatty Liver

“…More recently, CEUS has played a successful role in this pursuit, although there is little mention of the use of CEUS in international guidelines for the same application. Although MRI has been considered the gold standard, CEUS is highly competitive with MRI and can play an essential and critical role in characterizing detected liver masses 9–11 …”

“…Although MRI has been considered the gold standard, CEUS is highly competitive with MRI and can play an essential and critical role in characterizing detected liver masses. [9][10][11] CEUS, performed with microbubble contrast agents (MBCA), is safe, readily available, and widely accepted by patients. Its performance has no nephrotoxicity and no requirement for ionizing radiation.…”