An animal experimental study to assess the core tissue acquisition ability of endoscopic ultrasound-guided histology needles

BACKGROUND AND OBJECTIVES: Acquisition of core tissue on endoscopic ultrasound (EUS)-guided fine-needle aspiration has been regarded as important for establishing an accurate histological diagnosis. Recently, a new 20-gauge histology needle with reverse bevel (ProCore needle) and a 22-gauge needle with 3 novel symmetric heels (Acquire needle) have been developed. The aims of this animal experimental study were to assess the core tissue acquisition (TA) abilities of these new histology needles by comparing them with those of conventional 22-gauge needles and to evaluate the efficacy of suction for these needles. MATERIALS AND METHODS: Three experienced echoendoscopists performed EUS-guided TA with and without suction using 43 types of needles. The amount of obtained tissue specimens and blood contamination was assessed using a scoring system, and the weight of the obtained tissue specimens was measured using an electronic balance. RESULTS: The mean amount of core tissue score of the Acquire 22-gauge needle or ProCore 20-gauge needle was significantly higher than that of the conventional 22-gauge needles (Acquire 22-gauge needle vs. conventional 22-gauge needles: P = 0.024; ProCore 20-gauge needle vs. conventional 22-gauge needles: P = 0.001). There was no significant difference in the mean amount of core tissue score between the Acquire 22-gauge needle and the ProCore 20-gauge needle (P = 0.296). In the Acquire 22-gauge needle and ProCore 20-gauge needle, there was no significant difference between the mean amount of core tissue score with suction and that without suction (3.7 ± 0.4 vs. 3.5 ± 0.4, P = 0.734) although blood contamination increased (2.3 ± 0.7 vs. 1.6 ± 0.3, P = 0.061). CONCLUSION: The TA abilities of the ProCore 20-gauge needle and Acquire 22-gauge needle were better than those of the conventional 22-gauge needles. The efficacy of suction for the ProCore 20-gauge needle and Acquire 22-gauge needle was limited.