Virtual Bronchoscopic Navigation Combined with Ultrathin Bronchoscopy. A Randomized Clinical Trial

RATIONALE: In bronchoscopy, an ultrathin bronchoscope can be advanced to more peripheral bronchi. Because virtual bronchoscopic navigation (VBN) is a method to guide a bronchoscope under direct observation using VB images, VBN may be particularly useful when combined with ultrathin bronchoscopy. OBJECTIVES: This prospective multicenter study evaluated the value of VBN-assisted ultrathin bronchoscopy for diagnosing peripheral pulmonary lesions. METHODS: We randomly assigned 350 patients with peripheral pulmonary lesions (diameter, ≤30 mm) to VBN-assisted or non-VBN-assisted groups. An ultrathin bronchoscope (outer diameter, 2.8 mm) was introduced to the target bronchus using a VBN system in the VBN-assisted group, whereas only computed tomography axial images were referred to in the non-VBN-assisted group. Specimen sampling sites were verified using X-ray fluoroscopy. MEASUREMENTS AND MAIN RESULTS: Subjects for analysis included 334 patients. There was no significant difference in the diagnostic yield between the VBN-assisted group (67.1%) and the non-VBN-assisted group (59.9%; P = 0.173). The subgroup analysis showed that the diagnostic yield was significantly higher in the VBN-assisted group than in the non-VBN-assisted group for right upper lobe lesions (81.3% vs. 53.2%; P = 0.004); lesions invisible on posterior-anterior radiographs (63.2% vs. 40.5%; P = 0.043); and lesions in the peripheral third of the lung field (64.7% vs. 52.1%; P = 0.047). CONCLUSIONS: VBN-assisted ultrathin bronchoscopy does not improve the diagnostic yield for peripheral pulmonary lesions. However, the method improves the diagnostic yield for lesions in the subcategories (right upper lobe, invisible, peripheral third), warranting further study. Clinical trial registered with www.umin.ac.jp/ctr/ (UMIN 000001536).