Virtual reality obtained by the fusion of images can be applied to several fields of medicine leading to the so called "augmented reality". Since 2017 investigators have been using a new digital angiographic system (Discovery IGS 40, General Electrics), where fluoroscopy can be fused with pre-procedural CT o MRI. Specifically the present study aimed at verifying the advantages that fusion imaging could bring in EUS-guided drainage of post-pancreatitis fluid collection (PFC), i.e. pseudocysts or WON, in terms of more appropriate visualization, drainage approach and time needed for resolution.

17 drainages performed with traditional radiology (group 1) were retrospectively compared with 14 ones achieved with the fusion approach (group 2). The two population were homogenous for age, sex, pancreatitis etiology and indication for drainage whereas PFCs of group 2 were larger (663 cm3 vs 437 cm3), more frequently WON than pseudocysts and were treated more precociously. As for procedure, in the group 2, thanks to fusion imaging, endoscopists didn't need ever contrast media - that was pivotal with traditional radiology - to adequately define lesion morphology. LAMS (Axios) stents were placed mainly in group 2, while in group 1 other types of stent were used.

Inclusion Criteria:

• patients with post-pancreatitis PCF endoscopically drained

Exclusion Criteria:

• refuse to sign the informed consent

patient affected by moderate-severe pancreatits whio develops a PFC (WON or pseudocysts) that requires an endoscopic drainage