An experimental study to assess the best maneuver when using a reverse side-bevel histology needle for EUS-guided fine-needle biopsy

Background and study aims: Recently, ProCore™ was developed as an endoscopy ultrasound (EUS)-guided histology needle designed to address several current limitations of EUS-guided fine-needle aspiration (FNA). Nevertheless, tissue yield with the ProCore™ is not consistent. No standard technique has been established. This experimental study was conducted to ascertain the best maneuver when using the ProCore™. Patients and methods: We performed fine-needle aspiration and biopsy (FNAB) with a 22-gauge (G) ProCore™ using chicken tenderloin and liver. Six methods were used, with two needle movement techniques (natural speed and whipping back) and three negative pressures (no suction (NS), slow pull (SP), and 10-mL suction). Results: In cases using the “natural speed” technique, a significant difference in tissue yield was found with suction pressures in both tenderloin and liver (P