Identifying MRONJ-affected bone with digital fusion of functional imaging (FI) and cone-beam computed tomography (CBCT): case reports and hypothesis

Surgical debridement of medication-related osteonecrosis of the jaw (MRONJ) lesions is far less predictable than lesion resection. Margins for surgical debridement are guided by surrogate markers of bone viability, such as bleeding and bone fluorescence, which limit debridement to visibly necrotic bone. In contrast, surgical resection is extensive, including a substantial portion of surrounding bone. The concept that the MRONJ lesion is a composite of affected but viable (“compromised”) and necrotic bone is supported by histopathological data. Hence, removing only the necrotic bone during lesion debridement could inadvertently leave behind residual compromised bone in the lesion, subsequently contributing to persistence or reestablishment of the lesion. Using 2 case reports, this manuscript illustrates a novel assessment of the MRONJ lesion to enable demarcation of both the compromised and necrotic portions of the lesion. This assessment uses tumor-surveillance functional bone imaging data that may already be available for cancer patients with MRONJ and fuses these data digitally with computed tomography/cone-beam computed tomography imaging of the jaw obtained during MRONJ assessment. If validated, preoperative functional imaging-based assessment of the MRONJ lesion could enable surgeons to eliminate both the compromised and nonviable portions of the lesion precisely with conservative debridement, matching surgical resection in outcome.