Computer-assisted histometric analysis of tissue-engineered ovine bone.

OBJECTIVE: To develop a computer-assisted histometric technique that quantitatively determines the amount of regenerating bone, while excluding fibrovascular tissue and void spaces, in tissue-engineered bone constructs. To this end, a histometric technique was developed that couples digital tiling with adaptive, multiband color thresholding (AMBCT). STUDY DESIGN: To test the technique, a previously described model bone tissue-engineered construct filled with morcellized bone graft was employed. Histometric techniques were applied to quantify the amount of bone formed following eight weeks of implantation. RESULTS: The histometric technique was able to yield quantitative information regarding the amount of bone despite intrahistologic and interhistologic differences in staining. The technique is user friendly and highly automated. In addition to area fractions, the technique can provide bone ingrowth profiles as a function of geometry and implantation time. CONCLUSION: Digital tiling coupled with AMBCT offers an easy, fast and reproducible technique that aids in quantification of bone within histologic sections. In addition, the technique can be adapted to quantification of other tissues. Further studies are under way to investigate the potential of correlating the histometric technique with mechanical strength analyses of tissue-engineered bone specimens.