title: The usefulness of endobronchial ultrasonography-guided transbronchial needle aspiration at the lobar, segmental, or subsegmental bronchus smaller than a convex-type bronchoscope.
abstract: BACKGROUND
  Endobronchial ultrasonography-guided transbronchial needle aspiration (EBUS-TBNA) is a standard procedure for approaching the lesion adjacent to extrapulmonary bronchus. We started to use wedge insertion of a convex endobronchial ultrasound bronchoscope into bronchi narrower than the diameter of the bronchoscope itself to perform EBUS-TBNA. Our objective was to investigate the bronchus in which EBUS-TBNA was possible and safe.
  
  
  METHODS
  In this prospective study, we examined 15 lesions that were adjacent to lobar, segmental, or subsegmental bronchi narrower than the 6.9 mm external diameter of the convex scope. The cross-sectional area and maximum, minimum, and mean internal diameters of the airway lumen adjacent to the lesion were calculated using the measurement software. We investigated the airway branch in which EBUS-TBNA was possible, the narrowest airway diameter adjacent to the lesion for which insertion and diagnosis could be performed, the feasibility of puncture, and techniques for ensuring procedural success.
  
  
  RESULTS
  The mean cross-sectional area of the lumen for the 13 lesions that could be punctured was ≥ 15.9 mm2 and the mean internal diameter was ≥ 4.5 mm. Cytologic or histologic diagnosis by EBUS-TBNA was possible in 11 of the 15 cases. In 2 of the 4 undiagnosed lesions, the mean internal diameter was <4.5 mm, and the convex scope was unable to reach the lesion. There was no occurrence of complications in any case.
  
  
  CONCLUSIONS
  EBUS-TBNA can be performed by inserting a 6.9 mm EBUS bronchoscope into airways with a mean diameter ≥ 4.5 mm as measured on computed tomography before bronchoscopy.
authors.affiliation: Departments of *Chest Surgery §Radiology †Internal Medicine, Division of Respiratory and Infectious Disease, St Marianna University, School of Medicine, Kanagawa ‡Department of Surgery, Iwakuni Minami Hospital, Iwakuni, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Kurimoto
authors.forename: Takeo
authors.initials: T
authors.lastname: Inoue
authors.forename: Teruomi
authors.initials: T
authors.lastname: Miyazawa
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Morita
authors.forename: Shin
authors.initials: S
authors.lastname: Matsuoka
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D001980:Bronchi / Q000000981:diagnostic imaging / Q000473:pathology*; D020680:Bronchoscopes; D001999:Bronchoscopy / Q000379:methods*; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000473:pathology*; D015331:Cohort Studies; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000379:methods*; D006222:Hamartoma / Q000000981:diagnostic imaging / Q000473:pathology*; D006391:Hemangioma / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D009929:Organ Size; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014397:Tuberculosis, Pulmonary / Q000000981:diagnostic imaging / Q000473:pathology*