A retrospective study comparing the ultrathin versus conventional bronchoscope for performing radial endobronchial ultrasound in the evaluation of peripheral pulmonary lesions

BACKGROUND: Few studies have reported on the utility of ultrathin bronchoscopes (UTBs) for performing radial probe endobronchial ultrasound (EBUS). Herein, we describe our experience with UTB and conventional bronchoscope (CB) for performing radial EBUS. MATERIALS AND METHODS: This was a retrospective study comparing the diagnostic yield of a prototype UTB (external diameter 3 mm, working channel diameter 1.7 mm) versus CBs (external diameter ≥4.9 mm) in performing radial EBUS for the evaluation of peripheral pulmonary lesions (PPLs). Fluoroscopic guidance was not available. RESULTS: A total of 121 subjects (34, UTB; 87, CB; 69.4% males) with a mean (standard deviation [SD]) age of 55.2 (14.8) years underwent radial EBUS. The mean (SD) size of PPLs on computed tomography of the thorax was 22.2 (13.7) mm. The lesions were significantly smaller in the UTB group (16.4 vs 24.7 mm, P = 0.006). Eight lesions could be visualized within the lumen of the peripheral smaller bronchi with the UTB. The overall yield of radial EBUS was 52.9% and was similar in the two groups (UTB vs. CB, 55.9% vs. 51.7%; P = 0.7). The procedure time was significantly shorter in the UTB group. On multivariate logistic regression, the yield was similar in the two groups after adjusting for the size and location of the lesion and position of the radial probe in relation to the lesion. CONCLUSION: Despite smaller lesions, radial EBUS performed with the UTB was found to have similar efficacy to that performed with the CB. More lesions could be visualized endobronchially using the UTB making it an attractive alternative for performing radial EBUS.