title: Fluorodeoxyglucose positron emission tomography with computed tomography detects greater metabolic changes that are not represented by plain radiography for patients with osteonecrosis of the jaw.
abstract: OBJECTIVE
  Imaging is important to identify subclinical changes and for treatment planning in patients with osteonecrosis of the jaw (ONJ) exposed to antiresorptive therapy. The aim of this study was to compare the findings at radiography with those at fluorodeoxyglucose (FDG) positron emission tomography (PET) with computed tomography (CT) for patients with ONJ related to antiresorptive therapy.
  
  
  METHODS
  A cross-sectional retrospective analysis of patients with clinically identified ONJ lesions of the mandible was performed. Two imaging modalities were evaluated for each patient: plain radiography (ie, panoramic or periapical) and FDG PET/CT with 1-mm sections. Outcome variables for the radiographic findings were osteolytic and osteosclerotic bone changes. Outcome variables for FDG PET/CT images were localization of FDG uptake. Maximum standard uptake values (SUVmax) of abnormal FDG jaw uptake were recorded, in addition to the mean SUV of the contralateral normal mandible, and used to calculate the target-to-background ratio. Radiographic changes and FDG uptake were classified as local (ie, corresponding to exposed cortical bone) or diffuse (ie, local changes and changes extending beyond the margins of exposed bone) for each imaging technique. Local and diffuse changes detected by each imaging modality were described and the difference in detection was compared with the McNemar test.
  
  
  RESULTS
  Twenty-three patients with 25 clinically identified ONJ lesions were analyzed using radiography and FDG PET/CT. Differences were found in how radiography and FDG PET/CT detect local and diffuse changes associated with ONJ. Radiography showed local changes in 17 patients (68%), diffuse changes in 3 patients (12%), and no changes in 5 patients (20%), whereas FDG PET/CT imaging showed local changes in 17 patients (68%) and diffuse changes in 8 patients (32%). The McNemar test indicated that FDG PET/CT imaging was less likely to miss a lesion (P < .001). Mean SUVmax was 6.59, and the mean target-to-background ratio was 5.37.
  
  
  CONCLUSIONS
  The results of this study show that FDG PET/CT detects local and diffuse metabolic changes that may not be represented by plain radiography for patients with ONJ related to antiresorptive therapy. The target-to-background ratio allowed the discrimination between ONJ lesions and background changes. Future studies are necessary to determine whether FDG PET/CT can determine risk and facilitate management of ONJ.
authors: Clinical Associate Professor, Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, New York University Langone Medical Center and Bellevue Hospital Center, New York, NY. Electronic address: kef3@nyu.edu.
authors: Kenneth E
authors: KE
authors: Fleisher
authors: Fellow, Division of Nuclear Medicine, Department of Radiology, New York University Langone Medical Center, New York, NY.
authors: Roy A
authors: RA
authors: Raad
authors: Assistant Professor of Radiology, University of Saskatchewan, Saskatoon, SK, Canada.
authors: Rajan
authors: R
authors: Rakheja
authors: Fourth Year Dental Student, New York University College of Dentistry, New York, NY.
authors: Vikas
authors: V
authors: Gupta
authors: Clinical Assistant Professor, Department of Oral and Maxillofacial Pathology, Radiology, and Medicine, New York University College of Dentistry, New York, NY.
authors: King Chong
authors: KC
authors: Chan
authors: Associate Professor and Section Chief, Division of Nuclear Medicine, Department of Radiology, New York University Langone Medical Center, New York, NY.
authors: Kent P
authors: KP
authors: Friedman
authors: Associate Professor, Division of Nuclear Medicine, Department of Radiology, New York University Langone Medical Center, New York, NY.
authors: Karen A
authors: KA
authors: Mourtzikos
authors: Senior Research Scientist, Department of Epidemiology and Health Promotion, New York University College of Dentistry, New York, NY.
authors: Malvin
authors: M
authors: Janal
authors: Professor and Chair, Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, New York University Langone Medical Center and Bellevue Hospital Center, New York, NY.
authors: Robert S
authors: RS
authors: Glickman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000000981:diagnostic imaging*; D050071:Bone Density Conservation Agents / Q000009:adverse effects; D001943:Breast Neoplasms / Q000188:drug therapy; D003430:Cross-Sectional Studies; D004164:Diphosphonates / Q000009:adverse effects; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007093:Imidazoles / Q000009:adverse effects; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008336:Mandibular Diseases / Q000139:chemically induced* / Q000000981:diagnostic imaging; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D016300:Radiography, Bitewing / Q000379:methods; D011862:Radiography, Panoramic / Q000379:methods; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014081:Tooth Extraction; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D000077211:Zoledronic Acid