Open-Mouth Bone Scintigraphy Is Better than Closed-Mouth Bone Scintigraphy in the Diagnosis of Temporomandibular Osteoarthritis

PURPOSE

Closed-mouth bone scintigraphy (CM scan) and closed-mouth single-photon emission computed tomography (CM SPECT) are used for conventional evaluation of osteoarthritis of the temporomandibular joint (TMJ). However, the adequacy of open-mouth bone scintigraphy (OM scan) has not yet been evaluated. Therefore, the purpose of this study was to compare the diagnostic performance of CM scan, CM SPECT, and OM scan.

METHODS

Thirty-six patients with suspicion of an abnormality of the TMJ and who underwent a (99m)Tc-HDP CM scan, CM SPECT, and an OM scan were enrolled. The scans were assessed visually for the presence of positive focal uptake in the TMJ. Osteoarthritis was defined as arthralgia plus crepitus or radiologic signs of arthrosis.

RESULTS

Of 72 TMJs, 21 (29.2 %) were diagnosed with osteoarthritis. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 90.5 %, 49.0 %, 42.2 %, 92.6 % and 61.1 % for the CM scan, 81.0 %, 58.8 %, 44.7 %, 88.2 % and 65.3 % for CM SPECT, and 81.0 %, 82.4 %, 65.4 %, 91.3 % and 81.9 % for the OM scan, respectively. The accuracy of the OM scan was higher than that of CM SPECT and the CM scans (p = 0.004 and p < 0.001, respectively).

CONCLUSIONS

The OM scan was more accurate than the conventional CM scan and even CM SPECT for diagnosing TMJ osteoarthritis.

Flow and function in machine-preserved kidneys

One hundred machine-preserved cadaver kidneys were transplanted irrespective of their flow rates on the preservation machine. Twenty-five per cent had flows of below 100 ml/min and 11 per cent had flows of below 80 ml/min. There was no correlation between the flow rate and function at 1, 3 or 12 months. There was no difference in the flow rate between those kidneys which functioned immediately and those which never functioned. A fall in flow rate was associated with acute tubular necrosis of longer duration but eventual function was not impaired. There was a higher incidence of early aggressive rejection in kidneys which functioned immediately. Preservation failure per se is a rare cause of primary non-function. Adherence to a policy of ignoring the flow characteristics of machine-preserved kidneys could make up to 25 per cent more kidneys available for transplantation.