Semi-automatic image-analysis applied to the quantification of bone microstructure

Bone microstructure can be quantified by methods ranging from simple manual techniques to fully automatic image analysis systems. We describe a semi-automatic method, developed in BASIC and running on a laboratory microcomputer. Its core is based on two special algorithms for image conversion and for calculation. These two algorithms produce quantifying characteristics for any irregularly shaped structure, as defined by one or more open or closed contour lines. The quantification of these structural parameters relies only on contour line digitization. The improved efficiency of this semi-automatic method is a consequence of combining automatic calculations and human assistance. The structural parameters chosen were for a specific research project; the correlation between mechanical and microstructural properties of cortical bone, but they may readily be changed as circumstances demand.