Quantifying layer-specific thicknesses in porcine large intestine using X-ray microscopy

Accurate quantification of the individual layers of the intestinal wall is essential for biomechanical modeling and the development of gastrointestinal medical devices. Traditional microscopy techniques, though widely used, are limited by their two-dimensional nature and potential for tissue distortion due to complex sample preparation. This study evaluates X-ray microscopy (XRM) as a nondestructive, three-dimensional alternative for measuring the thicknesses of the four major layers of porcine large intestinal tissue: serosa, muscularis externa, submucosa and mucosa. Using the ZEISS Xradia 620 Versa, XRM scans were compared to standard light microscopy. XRM successfully visualized all four layers and yielded thickness measurements that were consistent with those obtained via standard microscopy, despite natural biological variability. Notably, XRM scans allowed for 3D reconstructions of tissue vasculature and did not need extensive preparation or staining. These findings establish XRM as a powerful and practical method for morphological analysis of soft tissues and offer the first reported absolute layer thicknesses for each layer of porcine large intestinal tissue, which can be used in layer-specific constitutive biomechanical models.