Background/Objectives: Transabdominal ultrasonography (TUS) is widely used for the detection of gallbladder lesions (GBLs), but differentiating malignant lesions from non-malignant lesions remains challenging. Microvascular flow imaging (MVFI), including superb microvascular imaging, detective flow imaging, and B-flow, enables visualization of low-flow vessels without contrast agents. This study aimed to characterize MVFI vascular features of GBLs and evaluate their reproducibility. Methods: We retrospectively analyzed 42 patients with GBLs who underwent TUS between March 2022 and December 2025. Two blinded readers independently assessed B-mode and MVFI findings. The evaluated MVFI findings included vascular flow detection, number of basal vessels, vessel shape, vessel thickness, and vessel irregularity. Interobserver agreement was assessed using Cohen’s kappa coefficient, and imaging findings were compared between invasive malignant and non-malignant lesions. Results: Of the 42 lesions, 10 were invasive malignant and 32 were non-malignant. Vascular signals were detected in all invasive malignant lesions and in 21 of 32 non-malignant lesions. Multiple basal vessels and vessel dilation were more frequently observed in invasive malignant lesions. Interobserver agreement was excellent for the number of basal vessels (κ = 0.91) and good for vessel thickness (κ = 0.72), indicating that these findings were more reproducible than other MVFI features. Conclusions: MVFI enables visualization of intralesional vascular features in GBLs. Multiple basal vessels and vessel dilation were associated with invasive malignancy and showed favorable reproducibility. These findings may serve as candidate imaging markers for future prospective validation.

Background/Objectives: The role of peroral pancreatoscopy (POPS) in patients with main-duct and mixed-type intraductal papillary mucinous neoplasm (MD/mixed-IPMN) remains unclear. This retrospective multicenter case series aimed to evaluate the feasibility and safety of POPS using the 9-Fr eyeMAX and to describe additional intraductal findings, potential surgical impact, and biopsy–surgery concordance. Methods: Consecutive patients with MD/mixed-IPMN in whom POPS was attempted between May 2023 and September 2025 were retrospectively analyzed. Pre-POPS imaging findings, POPS findings, procedural outcomes, adverse events, surgical outcomes, and concordance between POPS-guided biopsy and surgical pathology were evaluated. Results: Among the 20 patients, 14 were men, and the median age was 74.5 years (range, 46–83 years). IPMNs were classified as main-duct type in five patients (25%) and mixed type in 15 (75%). On endoscopic ultrasonography, mural nodules were identified in 14 patients (70%), with a median diameter of 11 mm (range, 3–25 mm). Endoscopic papillary intervention was performed in 6 patients (30%). The technical success rate of POPS insertion was 95% (19/20). Mural nodules were detected by POPS in 17 patients (85%), and biopsy under POPS guidance was performed a median of 5 times (range, 1–10). The adequate tissue sampling rate was 86% (88/102). Mild post-ERCP pancreatitis occurred in 1 patient (5%). Twelve patients (60%) underwent surgery. The concordance rate between POPS-targeted biopsy and surgical pathology was 45% (5/11); however, R0 resection was achieved in 11 patients (92%). Conclusions: In this small retrospective case series, POPS using the 9-Fr eyeMAX was feasible and provided additional intraductal information in selected patients. However, its diagnostic role remains adjunctive because POPS-guided biopsy showed limited reliability.