Duct-focused digital subtraction pancreatography for pancreatic duct visualization: a retrospective pilot study.

BACKGROUND

Digital subtraction pancreatography (DSP) has been proposed as a technique to reduce background interference and facilitate pancreatic duct visualization during endoscopic procedures. However, objective evaluation of DSP image interpretability and its clinical applicability remains limited.

METHODS

This single-center retrospective cohort study included 21 pancreatic ductography procedures performed between September 2022 and October 2025, comprising 11 DSP cases and 10 conventional pancreatography cases. Two independent endoscopists evaluated DSP images using predefined criteria for main pancreatic duct (MPD) visualization, background suppression, and branch duct visualization on a 3-point scale. Interobserver agreement was assessed. Secondary outcomes included technical feasibility, radiation exposure, and procedure-related adverse events.

RESULTS

DSP was technically feasible in all cases (11/11, 100%), with successful acquisition of subtracted images using a single acquisition per procedure. In intra-individual image assessment of the 11 DSP cases, MPD visualization scores were identical between conventional and DSP images (2.91 vs. 2.91, p = 1.000), whereas branch duct visualization showed a numerical improvement with DSP (2.00 vs. 1.73, p = 0.063). Interobserver agreement assessed by weighted kappa demonstrated substantial reliability for branch duct visualization (κ = 0.74) and moderate reliability for background suppression (κ = 0.49). Median total radiation dose did not differ significantly between the DSP and conventional groups (31.0 vs. 48.3 mGy, p = 0.65). No procedure-related adverse events were observed.

CONCLUSIONS

DSP provided generally interpretable pancreatic duct visualization with background suppression and was feasible without increasing radiation exposure. Although no clear advantage over conventional pancreatography was demonstrated, DSP may serve as a supplementary imaging technique in selected cases where background interference limits duct visualization. Further studies are warranted to define its clinical indications.