Comparison between semi-automated segmentation and manual point-counting methods for quantitative analysis of histological sections.

The aim of the present study was to compare results obtained using the manual point-counting method with results obtained using the semi-automated segmentation method, in the quantitative evaluation of histological sections by light microscopy. The tongues of 40 rats (Ratus norvergicus) were processed using the paraffin technique, in which a 5-mum-thick tissue slice cut from each tongue is stained with picrosirius and methyl green. Three digital images were captured randomly from each section, which were later converted to black-and-white. The collagen fibers shown in each image were quantified using the semi-automated segmentation method and the manual point-counting method. The results obtained using the 2 different quantification methods were compared using the paired t-test and Pearson's correlation test, with statistical analysis using the methods of Bland and Altman. The t-test indicated that there was no significant difference in results between the 2 different quan-tification methods. Pearson's correlation test indicated a strong correlation (r = 0.987), and a comparison of the methods using the Bland and Altman plot indicated no significant error. These findings indicate that both quantification methods can be reliably used to evaluate tissue sections, without discrepancies between the 2 methods.