This study evaluates the diagnostic utility of 3-phase bone scintigraphy for diagnosing osteoradionecrosis of the jaw (ORNJ).
Thirty-two consecutive patients with a history of radiation to the head and neck region (range, 62–70 Gy; mean, 68 Gy; median, 69 Gy) due to squamous cell cancer and suspected ORNJ underwent 3-phase bone scans after injection of 520 to 750 MBq of 99mTc-MPD. In addition to planar scans, tomographic images (SPECT) were acquired in the second phase and SPECT/CT images during the third phase. Histopathologic findings (n = 18) and clinical follow-up (n = 14) served as reference standard for osteoradionecrosis.
The first, second, and third phases of planar images were rated positive in 18/32 patients (56.3%), 25/32 (78.1%), and 27/32 patients (84.4%), respectively. The late SPECT was positive in all patients (32/32, 100%), respectively. Histopathologic findings available in 18/32 patients (56.3%) confirmed ORNJ in all subjects. Acute inflammation was histologically proven in 18/18 specimens (100%) and additional chronic inflammation in 12/18 (66.7%). In 13/18 (72.2%) specimens, superinfection was evident histopathologically. A photopenic defect with surrounding hypermetabolism, a reported hallmark of ORJN, was found in less than 5%.
The predominant scintigraphic pattern of osteoradionecrosis includes increased bone mineralization phase in all patients. Central photopenia, reportedly a typical bone scan finding in bisphosphonate-induced osteonecrosis, was not characteristic for ORNJ. A differentiation of acute from chronic inflammatory processes was not possible.
From the Departments of *Nuclear Medicine, and †Oral and Maxillofacial Plastic Surgery, University Hospital of Würzburg; ‡Institute of Pathology, University of Würzburg, Würzburg, Germany; and §Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA.
Received for publication June 26, 2013; revision accepted October 2, 2013.
Constantin Lapa and Christian Linz contributed equally to the work.
Conflicts of interest and sources of funding: none declared.
Reprints: Constantin Lapa, MD, Department of Nuclear Medicine, University Hospital of Würzburg, Oberdürrbacherstr 6, D-97080 Würzburg, Germany. E-mail: firstname.lastname@example.org.