Relations between radiograph texture analysis and microcomputed tomography in two rat models of bone metastases

Aims: Osteolytic (Walker 256, W256) and osteoblastic (Mat-LyLu, MLL) metastases were induced to investigate their effect on bone architecture by microcomputed tomography (microCT) and texture analysis of radiographs. Methods: Fischer and Copenhagen rats received an intracardiac injection with W256/MLL cells, respectively. Femur and tibia radiographs were analyzed by texture analysis with run lengths and fractal algorithms. Microarchitecture was analyzed on primary and secondary spongiosa by microCT. Results: W256 and MLL induced a decrease of trabecular bone mass, a disconnection of trabeculae and an increased conversion of plates into pillars. On radiographs and 3-dimensional models of W256 rats, a disappearance of the primary spongiosa was observed. On radiographs and 3-dimensional models of MLL rats, osteolytic lesions were observed as disseminated dark areas. Run length and fractal analyses were altered in both metastases. Conclusion:W256 and MLL cells induced two different patterns of osteolysis. Texture analysis of radiographs is a useful technique to explore trabecular bone changes. Copyright (c) 2006 S. Karger AG, Basel.