MRI of Mandibular Osteonecrosis Secondary to Bisphosphonates

Bisphosphonates are a group of drugs used in the treatment of oncology patients with bone metastases. However, in the past few years, osteonecrosis of the jaw has been reported as a serious complication of such treatment. The objective of this study was to examine the use of MRI in the assessment of bone lesions caused by this disease. Fourteen patients were studied who had been treated with i.v. bisphosphonates and had developed focal lesions of osteonecrosis of the jaw. These patients were referred by the stomatology department of Hospital General Universitario de Valencia. We evaluated both the morphology and the behavior of the lesions in T1, STIR, and after the administration of gadolinium. Twenty-six focal lesions were detected clinically and 36 were detected radiologically. All the clinically detected focal lesions were visible on MRI. There were 15 focal lesions detected radiologically that were not detected on clinical examination. In all patients, it was possible to assess bone involvement and involvement of the bone marrow, soft tissues, sinuses, and mandibular canal as well as the presence of adenopathy. MRI is an effective tool in the assessment of osteonecrosis of the jaw. The significance of focal lesions detectable on radiologic examination but without clinical correlation and their progression over time remains to be determined.