Quality of Lymph Node Visualization Using a Novel Slim Linear EBUS Bronchoscope vs a Conventional Linear EBUS Bronchoscope

Linear endobronchial ultrasound (EBUS) has revolutionized mediastinal interrogation; however, its utility is generally limited to central airways because of size constraints. A novel, slim, linear EBUS bronchoscope with an optional externalized balloon function to allow for a smaller outer diameter and increased flexibility has been developed. How does quality of lymph node visualization of the novel, slim, linear EBUS bronchoscope compare with that of a conventional EBUS bronchoscope, and what is the impact of the sleek external balloon? In this crossover, single-blind study, bronchoscopists performed linear EBUS on human cadavers. The bronchoscopists used two different bronchoscopes, a conventional EBUS bronchoscope (EB-530US; Fujifilm) and a slimmer, more flexible prototype (Fujifilm), to identify native lymph nodes with and without using a contact balloon. Images were recorded and de-identified, and a blinded independent review panel scored each de-identified image by using a Likert scale based on the ability to ascertain lymph node architecture (1 = poor, 2 = average, 3 = good, and 4 = excellent). Eleven bronchoscopists captured 348 individual lymph node images. The mean Likert scores for quality of lymph node visualization were as follows: conventional bronchoscope with balloon, 1.88; conventional bronchoscope without balloon, 1.80; prototype with external balloon, 1.76; prototype without balloon, 2.03. One-way analysis of variance revealed significant differences between the groups ( P < .01). A t test comparing the prototype without balloon and the current gold standard conventional with balloon (2.03 vs 1.88; P = .03) found a significant difference. There were no significant differences broadly between the prototype and conventional bronchoscope (1.89 vs 1.84; P = .19) or between balloon use and no balloon use (1.92 vs 1.82; P = .06). A novel, slim EBUS bronchoscope with increased flexion and no balloon showed noninferior quality of lymph node visualization in the mediastinum and hilum compared with the current gold standard bronchoscope, suggesting that further investigation in human trials is warranted.