^99mTc-Pertechnetateによる唾液腺機能検査

口腔内放射能活性の診断的価値

抄録

The function of the parotid glands were studied in 45 patients with parotid gland diseases, with the salivary glands affection systemic diseases, and with radiation injury of the parotid glands. As a control, the studies were done on 13 patients with no history of salivary gland disease.
The method is consisted of sequential scientigraphy using a gamma scintillation camera and simultaneous recordings of the time-activity curves for the regions over the parotid glands and Stensen's orifices. The examination was commenced immediately after intravenous injection of ^99mTc, and was continued up to 30 minutes. Salivation was stimulated with oral administration of tataric acid at 20 minutes after injection.According to whether the uptake, oncentration and excretion of ^99mTc were diminished or increased, the time-activity curves could be grouped in following four different patterns.
Pattern-A. Parotid gland activities continuously increased with time, whereas the orifice activities were no more than those of background and the curves maintained a lateau in shape. However, sudden decrease was observed in parotid gland activities immediately after salivary gland stimulation. Such a decrease always orrelated with a concurrent sharp increase over the orifice activities. This pattern was typical of controls.
Pattern-B. Both of the time-activity curves maintained a plateau during entire period of examination, although parotid gland activities were consistently higher than those of the orifices. Such reduced uptake with a reduction in salivary excretion was observed in parenchymal damage of parotid gland by parotid cancer, chronic parotitis, Sjögren's syndrome and post-irradiated sialopathies.
Pattern-C. Parotid glandular curves showed continuous increase with time, while the orifices ones were similar to those observed in control subjects. Such increased uptake with normal salivary excretion was noted in patients with oral mucositis, who had received chemotherapy and cobalt radiation for the carcinoma in the unilateral maxillary sinus.
Pattern-D. In spite of continuous increase of parotid gland activities, the orifice activities changed little in the entire time sequence. This pattern, which was characterized by increased concentration with a reduction in salivary excretion, corresponded with xerostomia resulting from sialosis.
Using this method, a clinician can determine the exact stage of glandular dysfunction.