Ethanol fixation method for heart and lung imaging in micro-CT
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The soft tissue imaging in micro-CT remains challenging due to its low intrinsic contrast. The aim of this study was to create a simple staining method omitting the usage of contrast agents for ex vivo soft tissue imaging in micro-CT.
Materials and methods
Hearts and lungs from 30 mice were used. Twenty-seven organs were either fixed in 97% or 50% ethanol solution or in a series of ascending ethanol concentrations. Images were acquired after 72, 168 and 336 h on a custom-built micro-CT machine and compared to scans of three native samples.
Ethanol provided contrast enhancement in all evaluated fixations. Fixation in 97% ethanol resulted in contrast enhancement after 72 h; however, it caused hardening of the samples. Fixation in 50% ethanol provided contrast enhancement after 336 h, with milder hardening, compared to the 97% ethanol fixation, but the visualization of details was worse. The fixation in a series of ascending ethanol concentrations provided the most satisfactory results; all organs were visualized in great detail without tissue damage.
Simple ethanol fixation improves the tissue contrast enhancement in micro-CT. The best results can be obtained with fixation of the soft tissue samples in a series of ascending ethanol concentrations.
KeywordsEthanol Micro-CT Mice Heart Lungs
The work was supported by the Charles University Grant Agency [GAUK 130 717] and from European Regional Development Fund-Project “Engineering applications of microworld physics” [No. CZ.02.1.01/0.0/0.0/16_019/0000766].
Compliance with ethical standards
Conflicts of interest
The authors declare that there is no conflict of interest regarding the publication of this paper.
All applicable institutional and national guidelines for the care and use of animals were followed.
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