title: Three dimensional imaging of paraffin embedded human lung tissue samples by micro-computed tomography.
abstract: BACKGROUND
  Understanding the three-dimensional (3-D) micro-architecture of lung tissue can provide insights into the pathology of lung disease. Micro computed tomography (µCT) has previously been used to elucidate lung 3D histology and morphometry in fixed samples that have been stained with contrast agents or air inflated and dried. However, non-destructive microstructural 3D imaging of formalin-fixed paraffin embedded (FFPE) tissues would facilitate retrospective analysis of extensive tissue archives of lung FFPE lung samples with linked clinical data.
  
  
  METHODS
  FFPE human lung tissue samples (n = 4) were scanned using a Nikon metrology µCT scanner. Semi-automatic techniques were used to segment the 3D structure of airways and blood vessels. Airspace size (mean linear intercept, Lm) was measured on µCT images and on matched histological sections from the same FFPE samples imaged by light microscopy to validate µCT imaging.
  
  
  RESULTS
  The µCT imaging protocol provided contrast between tissue and paraffin in FFPE samples (15 mm x 7 mm). Resolution (voxel size 6.7 µm) in the reconstructed images was sufficient for semi-automatic image segmentation of airways and blood vessels as well as quantitative airspace analysis. The scans were also used to scout for regions of interest, enabling time-efficient preparation of conventional histological sections. The Lm measurements from µCT images were not significantly different to those from matched histological sections.
  
  
  CONCLUSIONS
  We demonstrated how non-destructive imaging of routinely prepared FFPE samples by laboratory µCT can be used to visualize and assess the 3D morphology of the lung including by morphometric analysis.
authors.affiliation: μ-VIS Centre, Faculty of Engineering and the Environment, University of Southampton, Southampton, United Kingdom.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Scott
authors.affiliation: James Hogg Research Centre, University of British Columbia, Vancouver, Canada.
authors.forename: Dragos M
authors.initials: DM
authors.lastname: Vasilescu
authors.affiliation: James Hogg Research Centre, University of British Columbia, Vancouver, Canada.
authors.forename: Katherine A D
authors.initials: KA
authors.lastname: Seal
authors.affiliation: μ-VIS Centre, Faculty of Engineering and the Environment, University of Southampton, Southampton, United Kingdom.
authors.forename: Samuel D
authors.initials: SD
authors.lastname: Keyes
authors.affiliation: μ-VIS Centre, Faculty of Engineering and the Environment, University of Southampton, Southampton, United Kingdom.
authors.forename: Mark N
authors.initials: MN
authors.lastname: Mavrogordato
authors.affiliation: James Hogg Research Centre, University of British Columbia, Vancouver, Canada.
authors.forename: James C
authors.initials: JC
authors.lastname: Hogg
authors.affiliation: μ-VIS Centre, Faculty of Engineering and the Environment, University of Southampton, Southampton, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Sinclair
authors.affiliation: Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Warner
authors.affiliation: James Hogg Research Centre, University of British Columbia, Vancouver, Canada; Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, Canada.
authors.forename: Tillie-Louise
authors.initials: TL
authors.lastname: Hackett
authors.affiliation: Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Lackie
mesh_terms: D005557:Formaldehyde; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008168:Lung / Q000098:blood supply / Q000000981:diagnostic imaging*; D016612:Paraffin Embedding; D016707:Tissue Fixation; D055114:X-Ray Microtomography / Q000379:methods*
chemical_list: D005557:Formaldehyde