Various diagnostic methods are employed for salivary gland diseases. Among these, salivary gland scintigraphy employing 99mTc-pertechnetate is widely used in determining both morphological and functional statuses. In this paper, we evaluated the diagnostic value of this method.
Fifty nine cases were examined in this study: 2 cases of acute sialoadenitis, 12 cases of chronic submandibular sialoadenitis, 14 cases of chronic parotitis, 4 cases of benign submandibular gland tumor, 7 cases of benign parotid tumor, 2 cases of malignant tumor, 3 cases of cyst, 3 cases of Sjögren's syndrome, 8 cases of xerostomia, and 4 cases of sialolithiasis.
99mTc-pertechnetate was administered i.v. at a dose of 5-10mCi. After about 10 minutes, antero-posterior, right lateral, and left lateral views of the face were obtained. Bilateral parotid and/or submandibular glands were selected as R.O.I.and time activity curves were obtained. As a stimulation test, lemon juice was administered after another 10 minutes, and anteroposterior views of the face were obtained.
An analysis was carried out with three parameters: accumulation patterns (AP), the secretory patterns after the stimulation test (SP) and the stimulatory sacretion ratio (SSR) expressed as the ratio of post-to pre-stimulation counts on the salivary glands.AP were subclassified into five images: defective, decreased, normal, increased and enlarged. SP were also subclassified into five patterns (A-E).
The following results were obtained:
1) “Defective” images were an aid to differentiation between tumors except Warthin's tumor and other diseases.
2) “Increased” image with tumorous swelling were strongly indicative of Warthin's tumor, but more detailed examinations were required.
3) Differences in accumulations in Sjögren's syndrome and xerostomia were useful in distinguishing between the two diseases.
4) SP was helpful in differentiating between Sjögren's disease and xerostomia.
5) The SSR was more effective than SP for evaluation of minuter secretory functions.
6) Salivary gland scintigraphy employing 99mTc-pertechnetate therefore appears to be an extremely useful diagnostic method for salivary gland diseases.
