FDG‑PET/CT for Global Assessment of the TMJ in HIV Patients Using Cocaine


Mukit, Tahina1, Shah, Simi S1, Mouminah, Alaa1, Raynor, William Y2, Werner, Thomas J3, Alavi, Abass3
Faculty / Advisor: Chang, Yu Cheng1
1University of Pennsylvania School of Dental Medicine, Department of Periodontics
2Drexel University College of Medicine, Radiology
3Hospital of the University of Pennsylvania, Radiology

Introduction

Cocaine use is associated with adverse health effects, one which includes teeth grinding, commonly known as bruxism. This can not only cause occlusal wear on teeth but can also affect the temporomandibular joint (TMJ) and potentially cause inflammation. For this study, we used 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) to detect inflammation of the mandibular condyle. Our aim was to assess the practicality of using FDG-PET/CT to discern the effects of cocaine on the TMJ and determine surrounding bone and soft tissue inflammation.

Methods

Sixty-four patients were imaged at a single time point and consisted of four different groups: A) HIV patients with cocaine use B) HIV patients without cocaine use C) HIV negative patients with cocaine use D) HIV negative patients without cocaine use. One FDG-PET/CT scan was obtained for each patient. Osirix MD software was used to manually delineate the regions of interest (ROIs) containing the left and right TMJs, each contained by the temporal bone and mandible. The global mean standardized uptake value (global SUVmean) was calculated in each subject as the average SUV among all voxels contained within the left and right ROIs. Inter-rater reliability was assessed by Pearson correlation. An independent t test and Mann Whitney test were used to determine statistical significance between the independent groups.

Results

Three subjects were excluded due to imaging issues or unavailability image data. In total, 61 patients were evaluated. Excellent inter-rater reliability was observed (r = 0.997). The average global SUVmean of the four groups were: A)1.03 ± 0.27 B)1.12 ± 0.19 C)0.97 ± 0.16 D)1.06 ± 0.15. Independent t test revealed significant higher uptake in group B compared to group C (p = 0.03). Mann Whitney test comparing groups B and C was also significant (p = 0.02). Also, Mann Whitney test comparing pooled non-cocaine subjects (groups B and D) had significantly higher uptake than pooled cocaine subjects (groups A and C) (p = 0.007).

Conclusion

A reproducible method with excellent inter-rater reliability of evaluating the TMJ within HIV positive and cocaine addicts was found. Overall, the FDG uptake in non-cocaine subjects was significantly higher than cocaine subjects. However, these results contradict the hypothesis that higher FDG uptake would be found in cocaine subjects. Further investigation is necessary to understand the relationship between inflammation of the mandibular condyle and cocaine use. Assessing bone turnover at the TMJ with the PET tracer 18F-sodium fluoride may provide key additional information.