Histopathological findings affect quantitative values of single photon emission computed tomography in patients with antiresorptive agent-related osteonecrosis of the jaws.

Objectives: This study investigated the relationships between quantitative values calculated from bone single photon emission computed tomography/computed tomography (SPECT/CT) images and histopathological findings observed in surgical specimens from patients with antiresorptive agent-related osteonecrosis of the jaw (ARONJ); it sought to clarify histopathological factors that cause accumulation in bone SPECT/CT images of patients with ARONJ.

Methods: This study included 81 pathological specimens of 21 lesions obtained from 18 patients with ARONJ who underwent SPECT/CT and jaw resection. The maximum standardized uptake value (SUV) of each volume of interest of the specimens was calculated using RAVAT software. The ratio of the SUV to the mean value of SUV in temporal bone was termed rSUV. The rSUV and pathological findings (sequestration, degree of fibrosis, degree of trabecular bone destruction, degree of inflammatory cell infiltration, and vascularity) were compared using the Mann-Whitney U test and the Kruskal-Wallis test.

Results: In univariate analysis with rSUV as the dependent variable, the pathological findings of sequestration (P=0.058), degree of fibrosis (P=0.810), degree of trabecular bone destruction (P=0.237), degree of inflammatory cell infiltration (P=0.120), and vascularity (P=0.111) showed no significant difference among the groups for each variable.

Conclusions: We found no association between quantitative values in bone SPECT/CT and histological changes in ARONJ, probably because bone SPECT/CT has limited spatial resolution. Limitations of this study may include the imaging findings of a decrease in tracer accumulation because of an involucrum of necrosed bone, various histopathological findings in ARONJ, and failure to consider the effect of preoperative anti-inflammatory treatment.