Reducing soft-tissue shrinkage artefacts caused by staining with Lugol's solution.

Area of Science:

• Morphological research
• Developmental anatomy
• Medical imaging

Background:

• Diffusible iodine-based contrast-enhanced computed tomography (diceCT) is valuable for studying anatomy.
• Lugol's solution (Lugol) is an effective contrast agent but causes significant tissue shrinkage.
• The mechanism behind Lugol-induced shrinkage and prevention methods are poorly understood.

Purpose of the Study:

• To investigate the relationship between tissue shrinkage, solution osmolarity, and acidification during Lugol staining.
• To develop a method to prevent Lugol-induced tissue shrinkage without compromising contrast enhancement.

Main Methods:

• Tissue volume changes were quantified using 2D-segmented magnetic resonance and diceCT images analyzed with AMIRA software.
• Statistical analyses, including partial correlation and stepwise regression, were employed to determine the cause of shrinkage.
• A buffered Lugol's solution (B-Lugol) was developed and tested for its efficacy in preventing shrinkage.

Main Results:

• Acidification of Lugol's solution was identified as the primary cause of tissue shrinkage.
• The developed buffered Lugol's solution (B-Lugol) effectively prevented tissue shrinkage by stabilizing the solution's pH.
• Staining efficacy was maintained with B-Lugol, demonstrating no compromise in contrast enhancement.

Conclusions:

• Acidification is the main driver of tissue shrinkage in Lugol-enhanced diceCT.
• Buffered Lugol's solution (B-Lugol) offers a viable solution to prevent shrinkage, improving anatomical research accuracy.
• This modification requires minimal adaptation to existing diceCT staining protocols.