Study objective: To assess the ability of endobronchial ultrasonography (EBUS) using a guide sheath (EBUS-GS) to diagnose peripheral pulmonary lesions.
Method: We devised a technique for EBUS-GS covering a miniature probe, and 150 lesions were evaluated in a prospective open study. In this procedure, the probe covered by a guide sheath is introduced into the lesion via the working channel of a bronchoscope. The probe is withdrawn, while the guide sheath is left in situ. A brush or biopsy forceps is introduced through the guide sheath into the lesion.
Results: One hundred sixteen of 150 EBUS-GS procedures (77%) were diagnostic. Cases in which the probe was located within the lesion had a significantly higher diagnostic yield (105 of 121 cases, 87%) than when the probe was located adjacent to it (8 of 19 cases, 42%) [p < 0.0001, χ2]. The diagnostic yield from EBUS-GS in lesions ≤ 10 mm (16 of 21 lesions, 76%), >10 to ≤ 15 mm (19 of 25 lesions, 76%; p = 0.99, χ2), >15 to ≤ 20 mm (23 of 35 lesions, 66%; p = 0.41, χ2), and > 20 to ≤ 30 mm (33 of 43 lesions, 77%; p = 0.96, χ2) were similar, demonstrating the efficacy of EBUS-GS even in lesions ≤ 10 mm in diameter. In 54 of 81 lesions ≤ 20 mm, fluoroscopy was not able to confirm whether the forceps reached the lesion. However, the yield was the same with (67%, 18 of 27 lesions) and without (74%, 40 of 54 lesions) successful fluoroscopy (p = 0.96, χ2). Moderate bleeding occurred in two patients (1%); there were no other complications.
Conclusions: EBUS-GS is a useful method for collecting samples from peripheral pulmonary lesions, even those too small to be visualized under fluoroscopy.