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Ethanol fixation method for heart and lung imaging in micro-CT

  • Matej Patzelt
  • Jana MrzilkovaEmail author
  • Jan Dudak
  • Frantisek Krejci
  • Jan Zemlicka
  • Jakub Karch
  • Vladimir Musil
  • Jozef Rosina
  • Viktor Sykora
  • Barbora Horehledova
  • Petr Zach
Original Article
  • 22 Downloads

Abstract

Purpose

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.

Results

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.

Conclusions

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.

Keywords

Ethanol Micro-CT Mice Heart Lungs 

Notes

Funding

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.

Ethical statement

All applicable institutional and national guidelines for the care and use of animals were followed.

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Copyright information

© Japan Radiological Society 2019

Authors and Affiliations

  • Matej Patzelt
    • 1
    • 2
    • 3
  • Jana Mrzilkova
    • 1
    • 2
    • 3
    Email author
  • Jan Dudak
    • 1
    • 2
    • 4
    • 5
  • Frantisek Krejci
    • 1
    • 2
    • 4
  • Jan Zemlicka
    • 1
    • 2
    • 4
  • Jakub Karch
    • 1
    • 2
    • 4
    • 5
  • Vladimir Musil
    • 1
    • 2
    • 3
    • 6
  • Jozef Rosina
    • 1
    • 2
    • 5
    • 7
  • Viktor Sykora
    • 8
  • Barbora Horehledova
    • 9
  • Petr Zach
    • 1
    • 2
    • 3
  1. 1.Specialized Laboratory of Experimental Imaging, Third Faculty of MedicineCharles UniversityPragueCzech Republic
  2. 2.Institute of Experimental and Applied Physics and Faculty of Biomedical EngineeringCzech Technical University in PraguePragueCzech Republic
  3. 3.Department of Anatomy, Third Faculty of MedicineCharles UniversityPragueCzech Republic
  4. 4.Institute of Experimental and Applied PhysicsCzech Technical University in PraguePragueCzech Republic
  5. 5.Faculty of Biomedical EngineeringCzech Technical University in PragueKladnoCzech Republic
  6. 6.Centre of Scientific Information, Third Faculty of MedicineCharles UniversityPragueCzech Republic
  7. 7.Department of Medical Biophysics and Informatics, Third Faculty of MedicineCharles UniversityPragueCzech Republic
  8. 8.Center for Experimental Biomodels, First Faculty of MedicineCharles UniversityPragueCzech Republic
  9. 9.Department of Radiology and Nuclear MedicineMaastricht University Medical CenterMaastrichtThe Netherlands

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