Comparison of the harvest volume between maneuvers of endobronchial ultrasound-guided transbronchial needle aspiration including the “cross-fanning technique”

Abstract

Recently, a certain volume of biopsy specimens has been required for genetic testing of tumors using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). This study aimed to verify the superiority of our newly devised EBUS-TBNA biopsy technique, the “cross-fanning technique,” which combines rotation and up-down maneuvers, by comparing its harvest volume with that of other maneuvers. Using a bronchoscope simulator, ultrasonic bronchoscope, and 21-gauge puncture needle, we compared the weight of silicone biopsy specimens obtained by the following 4 procedures: Conventional maneuver; Up-down maneuver; Rotation maneuver, and; Cross-fanning technique. Each procedure was repeated 24 times in total, rotating the sequences of the maneuvers, and the operator/assistant pair to align the conditions. The means ± standard deviations of the sample volumes for each puncture technique were as follows: 2.8 ± 1.2 mg; 3.1 ± 1.6 mg; 3.7 ± 1.2 mg, and; 3.9 ± 1.2 mg. There was a significant difference between the 4 groups (P = .024). The post hoc test showed a statistically significant difference between techniques A and D (P = .019). This study showed that the cross-fanning technique might contribute to the increased volume of tissue samples obtained by EBUS-TBNA biopsy.