Deep learning-reconstructed hepatobiliary MRI: Enhancing biliary delineation, lesion margin sharpness, and small lesion detection.

OBJECTIVE: To evaluate the comparative performance of a deep learning-reconstructed T1-weighted volumetric interpolated breath-hold examination (DL VIBE) on hepatobiliary phase MRI against the conventional T1 VIBE in biliary tree visualization, lesion detection, and artifact suppression. MATERIALS AND METHODS: This retrospective study included 94 patients with suspected hepatic lesions (145 lesions, March-May 2025). All underwent gadoxetic acid-enhanced MRI at hepatobiliary phase using DL-VIBE (1.5 mm slice thickness) and conventional VIBE (3.0 mm). Blinded evaluations assessed biliary anatomy, lesion margins, and image quality through quantitative metrics (edge rise distance [ERD], CNR) and qualitative scoring. RESULTS: DL-VIBE demonstrated superior biliary visualization with 163 % higher tertiary duct detection (2.45 vs. 0.93 branches, p < 0.001) and improved continuity scores (2.97 vs. 2.60, p < 0.001). Lesion margins showed significantly improved sharpness (ERD: 0.93 ± 0.50 mm vs. 1.51 ± 0.10 mm; P < 0.001), while lesion detection rates were significantly higher overall (97.2 % vs. 91.0 %; P = 0.005) and particularly for micro lesions (96.3 % vs. 87.6 %; P = 0.004). DL-VIBE reduced image noise (3.82 vs. 2.25, p < 0.001) and suppressed ringing artifacts (3.55 vs. 2.30, p < 0.001) while maintaining bile duct CNR gains (230.50 vs. 135.14, p < 0.001), though with marginally lower texture naturalness (2.85 vs. 3.45, p = 0.001). CONCLUSION: DL-VIBE improves biliary microanatomy delineation, lesion margin resolution, and small lesion detection in gadoxetic acid-enhanced hepatobiliary MRI, suggesting clinical utility for precision imaging within standard breath-hold durations. CLINICAL RELEVANCE STATEMENT: DL-reconstructed 1.5-mm HBP VIBE serves as an improved alternative to conventional 3-mm VIBE, offering enhanced tertiary bile duct visualization and subcentimeter lesion detection for better clinical decision-making.