title: The diagnostic utility of endobronchial ultrasonography with a guide sheath and tomosynthesis images for ground glass opacity pulmonary lesions.
abstract: BACKGROUND
  With the widespread use of computed tomography (CT), the frequency of discovering ground glass opacity (GGO) pulmonary lesions has increased. There have been some reports on surgery or transthoracic needle aspiration (TTNA) for diagnostic sampling of GGOs but none on transbronchial biopsy (TBB). The purpose of this study was to evaluate the diagnostic utility of chest tomosynthesis images and TBB through endobronchial ultrasonography with a guide sheath (EBUS-GS) for GGO.
  
  
  METHODS
  This study included 40 patients (19 men, 21 women; age 66.9±8.7 years, mean ± standard deviation, SD). The mean lesion diameter was 22±10 mm (mean ± SD). Chest tomosynthesis images served as maps prior to bronchoscopic sampling using radial EBUS probe with a guide sheath kit.
  
  
  RESULTS
  The overall diagnostic yield of EBUS-GS-guided TBB was 65.0% (26 of 40 lesions). In a multivariate analysis, diagnostic yield of lesions with EBUS images (79.2%, 19 of 24 cases) was significantly higher than those lesions without EBUS images detected (43.8%, 7 of 16 cases) (P=0.017). Detectability on chest tomosynthesis was not a significant contributing factor. Only one complication was observed: pneumothorax that did not require chest tube drainage.
  
  
  CONCLUSIONS
  TBB through EBUS-GS can be considered as one of the diagnostic methods for GGO. Further technological development is required to identify the location of the target GGO lesion more precisely.
authors.affiliation: Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Izumo
authors.affiliation: Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Sasada
authors.affiliation: Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan.
authors.forename: Christine
authors.initials: C
authors.lastname: Chavez
authors.affiliation: Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tsuchida
keywords: Bronchoscopy and interventional techniques; chest tomosynthesis; endobronchial ultrasonography with a guide sheath (EBUS-GS); ground glass opacity (GGO); lung cancer