Diagnostic performance of quantitative bone SPECT/CT in patients with suspected osteomyelitis of the jaw

Objectives: To investigate the diagnostic performance of quantitative bone single photon emission computed tomography (SPECT)/computed tomography (CT) in patients with suspected osteomyelitis (OM) of the jaw.

Methods: We retrospectively reviewed bone SPECT/CT images of patients with suspected OM of the jaw. Blood pool planar image was obtained 1 min after intravenous injection of technetium-99m hydroxymethylene diphosphonate. And then, delayed regional planar and SPECT/CT images were obtained 4 hours after the injection. The maximum standardized uptake value (SUVmax) of the suspected OM lesion was measured from each SPECT/CT images. Receiver operating characteristic curve analysis was used to determine the optimal cut-off value of the SUVmax. The final diagnosis was established by surgery or clinical follow-up of at least 6 months.

Results: A total of 60 patients (10 male and 50 female; median age 76 y, range 21-90 y) were included in this study. Forty-nine patients (82%) were finally diagnosed with OM. Of the 23 patients with histologically confirmed OM, 18 patients (78%) had acute OM and 5 (22%) had chronic OM. In blood pool images, increased activity was noted more in patients with OM (46/49) than in patients without OM (4/11) (p < 0.001). The SUVmax of OM lesions was significantly higher than that of non-OM lesions (25.05 ± 10.88 vs. 11.39 ± 5.47; p < 0.001). There was no significant difference in SUVmax between acute and chronic OM lesions (18.11 ± 9.93 vs. 20.38 ± 12.78; p = 0.162).The best cutoff SUVmax for differentiating OM and non-OM was 16.4 and its sensitivity and specificity were 82% and 99%, respectively.

Conclusions: Both qualitative and quantitative analysis of bone SPECT/CT may be useful for the evaluation of patients with suspected OM of the jaw.