Accelerated Diffusion-Weighted Magnetic Resonance Imaging of the Liver at 1.5 T With Deep Learning-Based Image Reconstruction: Impact on Image Quality and Lesion Detection.

OBJECTIVE: To perform image quality comparison between deep learning-based multiband diffusion-weighted sequence (DL-mb-DWI), accelerated multiband diffusion-weighted sequence (accelerated mb-DWI), and conventional multiband diffusion-weighted sequence (conventional mb-DWI) in patients undergoing clinical liver magnetic resonance imaging (MRI). METHODS: Fifty consecutive patients who underwent clinical MRI of the liver at a 1.5-T scanner, between September 1, 2021, and January 31, 2022, were included in this study. Three radiologists independently reviewed images using a 5-point Likert scale for artifacts and image quality factors, in addition to assessing the presence of liver lesions and lesion conspicuity. RESULTS: DL-mb-DWI acquisition time was 65.0 ± 2.4 seconds, significantly (P < 0.001) shorter than conventional mb-DWI (147.5 ± 19.2 seconds) and accelerated mb-DWI (94.3 ± 1.8 seconds). DL-mb-DWI received significantly higher scores than conventional mb-DWI for conspicuity of the left lobe (P < 0.001), sharpness of intrahepatic vessel margin (P < 0.001), sharpness of the pancreatic contour (P < 0.001), in-plane motion artifact (P = 0.002), and overall image quality (P = 0.005) by reader 2. DL-mb-DWI received significantly higher scores for conspicuity of the left lobe (P = 0.006), sharpness of the pancreatic contour (P = 0.020), and in-plane motion artifact (P = 0.042) by reader 3. DL-mb-DWI received significantly higher scores for strength of fat suppression (P = 0.004) and sharpness of the pancreatic contour (P = 0.038) by reader 1. The remaining quality parameters did not reach statistical significance for reader 1. CONCLUSIONS: Novel diffusion-weighted MRI sequence with deep learning-based image reconstruction demonstrated significantly decreased acquisition times compared with conventional and accelerated mb-DWI sequences, while maintaining or improving image quality for routine abdominal MRI. DL-mb-DWI offers a potential alternative to conventional mb-DWI in routine clinical liver MRI.

Radiologic-Pathologic Discordance and Outcome After MRI-Guided Vacuum-Assisted Biopsy.

OBJECTIVE: The purpose of this study was to determine the rate, characteristics, and outcomes of discordant MRI-guided vacuum-assisted biopsy (VAB) in women with suspected breast cancer. MATERIALS AND METHODS: This retrospective study reviewed 1314 MRI-guided VABs performed in 1211 women between 2007 and 2013 and yielded 25 discordant results in 24 women. MRI characteristics; BI-RADS assessments; whether the lesion was missed, partially sampled, or excised at biopsy; and biopsy and surgical pathology results were reviewed. Statistical analyses were performed using Fisher exact and Mann-Whitney U tests. RESULTS: Among 1314 lesions that underwent MRI-guided VAB, 25 results were discordant (1.9%; 95% CI, 1.2-2.8%), and nine lesions with discordant results (36.0%, 95% CI, 18.5-56.9%) were malignant at surgical excision (three invasive ductal carcinoma and six ductal carcinoma in situ). There was no significant association between malignancy and lesion type, size, enhancement pattern, BI-RADS assessment, or clinical indication. Forty-four percent (11/25) of discordant lesions were missed, 48.0% (12/25) were partially sampled, and 8.0% (2/25) appeared to have been excised. Of the nine malignant lesions, 44.4% (4/9) discordant malignant lesions were missed, 44.4% (4/9) were partially sampled, and 11.1% (1/9) appeared to have been excised. Lesion sizes and types were similar in the missed and partially excised groups. CONCLUSION: The potential for false-negative results at MRI-guided VAB underscores the importance of radiologic-histologic correlation and imaging review after biopsy. Rebiopsy or excision in discordant cases is therefore recommended.

Frequency of Discordant Lesions and False-negative Cancers at Stereotactic Vacuum-assisted Biopsy.

RATIONALE AND OBJECTIVES: This study aimed to determine frequency of discordant lesions and discordant false-negative cancers at stereotactic vacuum-assisted biopsy (SVAB). MATERIALS AND METHODS: Institutional database was searched for discordant SVAB results between January 1, 2005 and December 31, 2012, in this retrospective institutional review board-approved Health Insurance Portability and Accountability Act-compliant study. Patient age, indication for initial mammogram, breast density, lesion size, Breast Imaging Reporting and Data System categorization, operator experience, biopsy needle gauge, biopsy histology, and final surgical histology of discordant lesions were collected and entered into a Microsoft Excel spreadsheet. Discordant rate and false-negative rates were calculated. Fisher exact test was used to assess prevalence of discordance using 11-Gauge needles versus 9-Gauge needles. Patient age, lesion Breast Imaging Reporting and Data System, operator days of experience, mammographic density, and lesion size were evaluated for association with false-negative discordant lesions using an exact Mann-Whitney U test. RESULTS: A total of 1861 SVABs were performed, 224 (12%) with an 11-Gauge VAB device and 1637 (88%) with a 9G Suros or Eviva device. Majority (1409 of 1861; 76%) of SVABs targeted calcifications. Twenty-three of 1861 (1.2%) discordant lesions were identified in 23 women. Seven of 23 (30%) discordant lesions were found to be cancers after final surgical pathology. Needle gauge was not associated with discordance. Operator experience was not associated with false-negative discordance. CONCLUSIONS: A relatively low discordance rate (1.2%) was observed. However, a high percentage (30%; range in literature 11.7%-53.8%) of our discordant lesions were false negatives. This study emphasizes the need for careful radiological-pathologic review after SVAB and for repeat biopsy or surgical excision in the setting of discordance.