Nonlinearity in the coefficient of thermal expansion of brain tissue

The coefficient of thermal expansion (CTE) in biological tissues is an integral parameter behind the applicationof electromagnetic energy to biomedical technologies; however, its behavior is far from being fully characterized. In this study, we apply digital image correlation (DIC) to non-invasively measure the microscale thermal expansions of recently excised embryonic E18 rodent brain tissue slices. Although the CTE has been measured previously in soft tissues, the literature surrounding the expansion of brain tissue remains sparse. Previous work in measuring the thermal expansion behavior of soft tissue often simplifies the results into a
single measurement of a linear CTE parameter and fails to convey the temperature-dependent nonlinearity that exists at physiologically-relevant temperatures.