1 research outputs found
Assessment of murine brain tissue shrinkage caused by different histological fixatives using magnetic resonance and computed tomography imaging
Especially for neuroscience and the
development of new biomarkers, a direct correlation
between in vivo imaging and histology is essential.
However, this comparison is hampered by deformation
and shrinkage of tissue samples caused by fixation,
dehydration and paraffin embedding.
We used magnetic resonance (MR) imaging and
computed tomography (CT) imaging to analyze the
degree of shrinkage on murine brains for various
fixatives. After in vivo imaging using 7 T MRI, animals
were sacrificed and the brains were dissected and
immediately placed in different fixatives, respectively:
zinc-based fixative, neutral buffered formalin (NBF),
paraformaldehyde (PFA), Bouin-Holland fixative and
paraformaldehyde-lysine-periodate (PLP). The degree of
shrinkage based on mouse brain volumes, radiodensity
in Hounsfield units (HU), as well as non-linear
deformations were obtained.
The highest degree of shrinkage was observed for
PLP (68.1%, P<0.001), followed by PFA (60.2%,
P<0.001) and NBF (58.6%, P<0.001). The zinc-based
fixative revealed a low shrinkage with only 33.5%
(P<0.001). Compared to NBF, the zinc-based fixative
shows a slightly higher degree of deformations, but is
still more homogenous than PFA.
Tissue shrinkage can be monitored non-invasively
with CT and MR. Zinc-based fixative causes the smallest
degree of brain shrinkage and only small deformations
and is therefore recommended for in vivo ex vivo
comparison studies