SU‐GG‐I‐150: Osteolytic Metastases Quantification From Digitized Radiographs

Purpose: To assess a gray level parameter in order to characterize osteolytic metastases and to compare with healthy bone on digitized radiographs. Method and Materials: The authors previously developed a computerized method in order to characterize healthy bone on digitized radiographs. We obtained an optimized healthy bone classification to compare with pathological bone: cortical, trabecular and flat bone. In the present study, 144 healthy bone and 45 osteolytic metastases radiographs corresponding to 189 different patients of both sexes were digitized (size of 0.175‐mm pixel and 4,096 gray levels). Osteolytic metastases were classified in non flat bone (OL1, n = 15) and flat bone (OL2, n = 30). The radiological images were processed using a lowpass filter and analyzed calculating gray level histograms on digitized radiographs. The parameter calculated was: mean gray level (MGL: 0 – 4096). Results: The results indicate that there are significant differences in mean values (p