title: Prospective controlled animal study on biopsy sampling with new flexible cryoprobes versus forceps: evaluation of biopsy size, histological quality and bleeding risk.
abstract: BACKGROUND
  Cryoextraction is a procedure used for the recanalization of obstructed airways caused by visible exophytic endobronchial tumor. Biopsy samples obtained by this technique have been shown to be useful for histological assessment.
  
  
  OBJECTIVE
  The aim of the present animal study was to systematically evaluate biopsy size, histological quality and bleeding risk after cryobiopsy with new, flexible cryoprobes in comparison with forceps biopsy, serving as the gold standard.
  
  
  METHODS
  Biopsies were obtained from anesthetized pigs with the flexible bronchoscopy technique, and evaluated histologically with respect to their size and quality. Bleeding frequency, bleeding duration and histological changes in the biopsy bed were also recorded.
  
  
  RESULTS
  Cryobiopsies were significantly larger than forceps biopsies. The size of cryobiopsies was dependent on the freezing time. The histological quality of the cryobiopsy specimenswas not impaired by the freezing process, whereas forceps biopsies showed typical crush artifacts. Despite the larger defects left in the tracheobronchial system after cryobiopsy, bleeding frequency and duration were not higher compared to forceps biopsy.
  
  
  CONCLUSIONS
  Since cryobiopsy sampling is not associated with a higher bleeding risk compared with forceps biopsy, this new biopsy technique offers--in addition to a good specimen quality--a safe and valuable tool with the potential of improving the outcome of diagnostic endoscopy.
authors.affiliation: Department of Pneumology and Critical Care Medicine, Helios Klinik Ambrock, University of Witten/Herdecke, Hagen, Germany. karl-josef.franke@helios-kliniken.de
authors.forename: Karl-Josef
authors.initials: KJ
authors.lastname: Franke
authors.forename: Dirk
authors.initials: D
authors.lastname: Theegarten
authors.forename: Claus
authors.initials: C
authors.lastname: Hann von Weyhern
authors.forename: Georg
authors.initials: G
authors.lastname: Nilius
authors.forename: Christiane
authors.initials: C
authors.lastname: Brueckner
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hetzel
authors.forename: Martin
authors.initials: M
authors.lastname: Hetzel
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Ruhle
authors.forename: Markus D
authors.initials: MD
authors.lastname: Enderle
authors.forename: Mara N I
authors.initials: MN
authors.lastname: Szyrach
mesh_terms: D000818:Animals; D001706:Biopsy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data; D001999:Bronchoscopy; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods*; D008168:Lung / Q000473:pathology*; D011446:Prospective Studies; D013552:Swine