Magnetic susceptibility matched fluid for neuroimaging assessed in histology and stereology: A pilot study

Area of Science:

• Neuroscience
• Biomedical Imaging
• Histology

Background:

• Ex vivo MRI offers ultra-high resolution imaging for validating postmortem brain samples.
• Perfluoropolyethers like Fomblin are used as immersion liquids due to their "proton free" nature, minimizing susceptibility artifacts.
• The impact of Fomblin on subsequent histological analyses has not been previously investigated.

Purpose of the Study:

• To evaluate the effect of Fomblin immersion on histochemical and immunohistochemical staining of rat brain samples.
• To assess Fomblin's impact on neuron counting and tissue thickness measurements using the optical fractionator method.

Main Methods:

• Rat brain samples were divided into two groups: Fomblin immersion (n=4) and control (n=4).
• Samples underwent histochemical (Nissl) and immunohistochemical (NeuN) staining.
• The optical fractionator method was employed to quantify total neuron counts and tissue thickness.

Main Results:

• Fomblin-exposed samples exhibited consistent NeuN and Nissl staining compared to controls.
• Staining quality, including color, evenness, and neuron visualization, remained unaffected by Fomblin.
• No significant differences in total neuron counts or tissue thickness were observed between the Fomblin and control groups.

Conclusions:

• Fomblin immersion does not appear to negatively affect short-term histochemical or immunohistochemical staining of rat brain tissue.
• Fomblin is likely compatible with histological analyses, including neuron counting and tissue thickness assessment.
• These findings support the use of Fomblin in ex vivo MRI studies requiring subsequent histological validation.