2019 Volume 69 Issue 2 Pages 97-104
Objectives: We evaluated the usefulness of a cooling system installed in the sliding microtome for paraffin-embedded tissue and digital image analysis (DIA) for thickness evaluation.
Methods: We prepared formalin-fixed paraffin-embedded fish sausage sample blocks and sliced the block using a microtome with (continuous cooling) or without (refrigerant cooling) a cooling system. DIA was used to evaluate the percentage of eosin-stained area (positive rate) on the specimen.
Results: The plotted mean positive rate of 2–8-μm thick specimens showed a logarithmic curve and showed a high correlation coefficient (R2>0.93). Hence, we utilized this plot as a standard curve to estimate specimen thickness. Under both cooling conditions, three individuals prepared 20 specimens that were 3-μm thick. The mean estimated thickness in the continuous and refrigerant cooling was <4μm and> 6μm2, respectively.
Conclusions: DIA is a useful technique in estimating specimen thickness. Our data showed that specimens prepared with conventional cooling (such as refrigerant cooling) were twice as thick as the setting value of the microtome.
