RADIOGRAPHICALLY NEGATIVE STRESS-RELATED BONE INJURY - MR-IMAGING VERSUS 2-PHASE BONE-SCINTIGRAPHY

Purpose. To assess the diagnostic value of MR imaging relative to two- phase bone scintigraphy in radiographically negative stress-related in juries. Material and Methods. Sixteen consecutive patients presenting with stress-related bone injuries and normal standard radiographs were examined with two-phase bone scans and MR imaging. MR imaging protoco ls varied according to the region to be examined. The MR and scintigra phic images were evaluated blindly and separately by respectively two radiologists and two nuclear medicine physicians. The standard of refe rence was represented by a combination of clinical and scintigraphic f indings as well as clinical follow-up. Results: For MR imaging, sensit ivity, specificity, and positive and negative predictive values for th e presence of stress-related injuries for the two readers were 69/63%, 100/80%, 100/91%, and 50/40%, respectively. Interobserver agreement w as good (kappa=0.62). For scintigraphy, all abnormal and normal findin gs were correctly identified. Conclusion: For patients with clinically suspected stress-related injuries and a low probability of other acti ve bone diseases (such as infection or neoplasm), bone scintigraphy sh ould be the initial imaging modality.