Three dimensional imaging of paraffin embedded human lung tissue samples by micro-computed tomography

Area of Science:

• Pulmonary medicine
• Medical imaging
• Histology

Background:

• Understanding lung 3D micro-architecture aids in diagnosing lung diseases.
• Micro computed tomography (µCT) has been used for lung histology and morphometry in fixed samples.
• Non-destructive 3D imaging of FFPE lung tissues is needed for retrospective analysis of archives.

Purpose of the Study:

• To demonstrate the utility of laboratory µCT for non-destructive 3D imaging of FFPE human lung tissue.
• To validate µCT imaging for assessing lung 3D morphology and morphometry.

Main Methods:

• Four FFPE human lung tissue samples were scanned using a Nikon metrology µCT scanner.
• Semi-automatic techniques were employed for segmenting 3D airway and blood vessel structures.
• Airspace size (mean linear intercept, Lm) was measured using µCT and validated against light microscopy of matched histological sections.

Main Results:

• The µCT protocol effectively differentiated tissue from paraffin in FFPE samples.
• The achieved resolution (6.7 µm voxel size) allowed for semi-automatic segmentation and quantitative airspace analysis.
• Lm measurements from µCT images showed no significant difference compared to histological sections, validating the imaging method.

Conclusions:

• Laboratory µCT provides a non-destructive method for visualizing and assessing the 3D morphology of FFPE lung tissue.
• This technique enables morphometric analysis of routinely prepared FFPE lung samples.
• The findings support the use of µCT for retrospective analysis of lung tissue archives.