Hiroyuki Oiki

A Case of Multiple Oncocytomas in the Bilateral Parotid Glands.

We report here a case of multiple oncocytomas that occured in the bilateral parotid glands. A 58-year-old female patient visited our hospital because of a mass that had existed for about 3 years in the left parotid region. Echography noted a hypoechoic lesion, CT scanning and MRI showed 3 masses in the left parotid gland, and 1 mass in the right parotid gland. There was a rapid and high accumulation of 99mTc in the tumor lesion by 99mTc-pertechnetate scintigraphy. A subtotal parotidectomy was performed on the left gland, and a partial parotidectomy of the superficial lobe was performed on the right gland. The histopathologic diagnosis was oncocytoma in the bilateral glands. Malignant oncocytoma that recur or metastasize have been previously reported. Oncocytoma is thought to be a difficult malignancy to diagnose, thus we needed to follow up carefully. To our knowledge, there have been no previous reports of multiple oncocytoma in the bilateral parotid glands. There has been no sign of recurrence or metastasis of the tumors. We also discuss the differential diagnosis, and the most appropriate treatment method.

Measuring Salivary Flow Function by 99mTc-Scintigraphy.

In a series of 115 subjects with various oral symptoms, salivary flow function was evaluated quantitatively by 99mTc-pertechnetate scintigraphy. For data processing, four regions of interest (ROI) were drawn over the parotid and submandibular glands. A time-activity curve was plotted for each ROI. The uptake rate and the secretion rate expressed as a percentage, were obtained from data that were subtracted by an additional ROI over the front used as background. Rates were calculated from a sample of the dose solution scanned under identical conditions, with the peak of the curve at rest and the bottom of the curve at stimuli.The uptake rates in the parotid and submandibular glands were equal. The number of cases showing that the secretion rate of the parotid gland was higher than that of the submandibular gland was three times the number of cases in which the secretion rate was higher in the submandibular gland. The uptake rate and the secretion rate of the parotid gland decreased gradually with age, but in the submandibular gland, neither rate changed with age. The uptake rate and the secretion rate in Sjogrens syndrome was significantly lower than those of other cases. In a significant number of cases, the side with a higher uptake rate in the parotid gland also showed a higher rate in the submandibular gland on the same side. This appears to suggest that a phase of salivary flow of the unilateral parotid gland synchronized with that of the ipsilateral submandibular gland.Our method of analysing salivary flow function appeared not only to show the same dynamics of salivary flow as previous reports showed, but also demonstrates the details of salivary flow dynamics.

Effect of Estrogen Replacement Therapy on Salivary Flow Dysfunction.

Changes in salivary flow rate were evaluated after administration of oral estrogen medication to 4 female patients with menopausal syndrome accompanied by various oral symptoms. Four patients showed symptoms including glossodynia (3 cases) and problems with taste (1 case). All patients were diagnosed with menopausal syndrome by a gynecologist and were administered oral estrogen medication. Salivary flow rate was evaluated by analysis of the time-activity curve of 99mTc-pertechnetate scintigraphy. Before treatment, 2 patients showed salivary flow hypofunction while the other 2 patients showed normal function. Complaints of each patient were resolved completely a few months after medication was prescribed. The uptake and secretion rates of the parotid glands in all patients increased after medication, but that of the submandibular gland did not change with medication. Thus, there appears to be a difference in the effect of estrogen on salivary flow rates between the parotid and submandibular gland. The results suggested that estrogen replacement therapy could be effective for salivary gland hypof unction.

Differential Diagnosis of Middle Ear Inflammatory Diseases by MRI Findings.

Although computed tomography can reveal a soft tissue mass in middle ear diseases as an area of increased density, it cannot differentiate cholesteatoma from other inflammatory tissue. We prospectively studied 30 patients with various middle ear inflammatory diseases, including inflammatory granulation tissue, cholesteatoma and cholesterin granuloma with magnetic resonance imaging (MRI) with or without Gd-DTPA enhancement. Cholesteatoma and inflammatory granulation tissue showed intensity ranging from low to high on Ti-weighted images and from high to very high on T2-weighted images. However, cholesteatoma showed either no enhancement or ring enhancement on MR imagings with Gd-DTPA, and it could be differentiated from the Gd-DTPA-enhanced inflammatory granulation tissue. Cholesterin granuloma showed very high intensity on both T1 and T2-weighted images. Therefore, MRI with Gd-DTPA is considered to be useful in the differential diagnosis of these middle ear diseases.

Tympanostomy tubes for children with otitis media with effusion.

Tympanostomy tubes were inserted in 76 ears under general anesthesia in our clinic between the beginning of 1984 and the end of 1987. After 6 months and 9 months, hearing was tested in two groups of patients: those with tympanostomy tubes for 3 months or longer and those with tubes present for less than 3 months. Hearing improvement was greater in the former than in the latter group. Otorrhea was observed in 11 ears (14%) while the tympanostomy tubes were in place. Cultures of the discharge suggested that the middle ear is more frequently infected through the Eustachian tube than through the external acoustic meatus. OME recurred in 26% after tympanostomy tubes were inserted, but in none of the ears with tympanostomy tubes for 12 months or longer.