Insulinoma detection and surgery planning: a comparative study of 5.0T MRI versus 3.0T MRI and MDCT.

Purpose: To compare the ability among 5.0T MRI, 3.0T MRI and MDCT in identifying insulinomas and determining the tumor-to-duct relationship.

Methods: A consecutive series of patients highly suspected of insulinomas were enrolled between October 2021 and February 2024, who underwent 5.0T MRI preoperatively, as well as 3.0T MRI or MDCT. The subjective and objective image quality, lesion-to-pancreas contrast, clarity of main pancreatic duct (MPD) and tumor-to-duct relationship at 5.0T, 3.0T MRI and MDCT were evaluated by three observers. The correlation between tumor-duct distance and clinically relevant postoperative pancreatic fistula (CR-POPF) risk was analyzed.

Results: Forty patients (14 men; mean age, 46.4 ± 16.5 years) with insulinomas were included in this study. 21 of them underwent both 5.0T and 3.0T MRI; and 38 of them underwent 5.0T MRI and MDCT. The intra- and inter-observer agreement of 5.0T MRI were good to excellent. 5.0T showed significantly higher subjective and objective image quality on T1WI and DWI compared to 3.0T (p < 0.05). Lesion-to-pancreas contrast was superior across all sequences at 5.0T compared to 3.0T(p < 0.05). A head-to-head comparison of patients who received both 5.0T and 3.0T MRI demonstrated that tumor detection was superior with 5.0T MRI (5.0T: 100%; 3.0 T: 92.0%, p < 0.05). Feasibility of tumor-to-duct relationship assessment was superior at 5.0T, compared to 3.0T and MDCT (93.2%, 64.0% and 52.3%, respectively, p < 0.05). Tumor-duct distance could predict CR-POPF after enucleation surgery (areas under the ROC curve 0.79, p = 0.01).

Conclusion: 5.0T MRI exhibits certain superiority in detecting insulinomas and assessing tumor-to-duct relationship compared to 3.0T MRI and MDCT.