Background and aims: To facilitate access for interventional EUS, flexible (nitinol) 19-G needles have been introduced to permit needle puncture even when the echoendoscope is in an angulated position, such as in the second part of the duodenum. The aims of the study were to evaluate the performance of a flexible 19-G needle during interventional EUS procedures and compare outcomes when the echoendoscope was in the straight versus angulated position.
Methods: A retrospective review was undertaken of 162 consecutive patients that underwent a variety of interventional EUS procedures with a flexible 19-G needle across five centers. Patients were subdivided into categories (straight or angulated) depending on the echoendoscope position used for obtaining access to the area of interest (Fig. 1). Fig. 1 Flexible 19-G needle design. a The needle is able to exit the sheath despite the rotated position. b The needle beveled needle tip RESULTS: In the entire cohort, needle-specific technical success was achieved in 93.2 %, procedural success in 85.2 %, and overall clinical success in 76.5 % of cases at a mean follow-up of 3.1 months. Needle-specific technical success was similar between the straight and angulated cohorts (94.0 vs. 91.2 %, p = 0.74). Procedural success (86.7 vs. 77.2 %, p = 0.05), and rate of clinical success was similar between the cohorts (83.3 vs. 86.4 %, p = 0.79), respectively. Overall adverse events were noted in 14.2 % of patients with no difference between the straight and angulated cohorts (p = 0.48).
Conclusions: This study demonstrates equivalent technical success, clinical success and safety of using a flexible 19-G needle in straight and angulated endoscope positions for interventional EUS. Therefore, a flexible needle may be considered where an angulated echoendoscope position is encountered.
Keywords: Angulated; Biliary drainage; Drainage; Endosonography; Flexible 19-G needle; Interventional endoscopic ultrasound; Pancreatic fluid collection; Therapeutic endoscopic ultrasound.