[Technetium uptake in the parotid gland. Value of functional parameters in Sjögren's syndrome]

Studies of the parotid function were performed on 22 subjects comprising 11 patients with Sjögren's syndrome and 11 normal controls using an Anger camera with digital data processing facility. After injection of 2 mCi of 99mTc-pertechnetate digital scintigrams of the face region were collected and stored onto magnetic tape. 50 minutes after injection the parotid glands were stimulated by administration of Pilocarpin. By subsequent processing of the data uptake curves were obtained for both parotid glands. In allowing for vascular activity three different methods were compared. The most satisfactory method with respect to discriminating the groups under study was using a background region located in the falx cerebri. From the corrected uptake curves a number of parameters were derived and their respective selectivity was investigated by statistical analysis. It is shown that the most suitable parameter characterizing the parotid function is given by the difference of maximum uptake before Pilocarpin stimulation and minimum uptake after stimulation.