Lemon Juice Stimulation Research Articles

A Functional Scoring System Based on Salivary Gland Scintigraphy for Evaluating Salivary Gland Dysfunction Secondary to 131I therapy in Patients with Differentiated Thyroid Carcinoma.

Radioiodine therapy with 131I (131I therapy) after total or near-total thyroidectomy has been established as an effective treatment for Differentiated Thyroid Carcinoma (DTC), but can induce dry mouth symptoms by salivary gland damage and impair the patients' quality of life. To propose a functional scoring system based on Salivary Gland Scintigraphy (SGS) findings that evaluates development of salivary gland dysfunction secondary to 131I therapy in patients with DTC. This retrospective study evaluated the records of 279 DTC patients who underwent SGS after one or more round(s) of 131I therapy, using 370 MBqof 99mTc-pertechnetate. The SGS results were assessed using a novel functional scoring system in the Parotid Glands (PGs) and Submandibular Glands (SMGs) according to visual evaluations based on a three-point uptake score, Washout Rate (%WR) score after lemon-juice stimulation, and functional score. The scores were compared among pre treatment, low-dose (<10 GBq), and high-dose (>10 GBq) groups and among pre treatment, symptom-positive, and symptom-negative groups. Risk factors for dry mouth were analyzed by univariate and multivariate logistic regression analyses. Dry mouth symptoms developed in 15.4% of the DTC patients after 131I therapy. The three-point uptake, %WR, and functional scores in both the PG and SMG were statistically significant between low-dose and high-dose groups, and between symptom-positive and symptom-negative groups. The PG/SMG functional scores were independent risk factors for dry mouth (odds ratio, 0.03 and 0.0007 respectively). SGS-based PG and SMG functional scores were effective biomarkers to objectively evaluate salivary gland dysfunction, with the high strength of association with dry mouth symptoms.

Chewing-gum stimulation did not reduce the absorbed dose to salivary glands during radioiodine treatment of thyroid cancer as inferred from pre-therapy (124)I PET/CT imaging.

BackgroundThe goal of this prospective study was to estimate the absorbed (radiation) doses to salivary glands in radioiodine therapy of thyroid cancer under chewing-gum stimulation using 124I positron emission tomography (PET)/computed tomography (CT) imaging.MethodsDuplex ultrasonography was conducted in three test persons for visual comparison of the glandular blood flow with three different stimulation types (no stimulation, chewing tasteless gum base, sucking on lemon slices). Ten patients with newly diagnosed differentiated thyroid cancer received 124I PET/CT dosimetry after thyroidectomy and prior to radioiodine therapy. Patients underwent a series of three 124I PET/CT scans (4, 24, and ≥96 h after administration of 23 MBq 124I). They were instructed to chew gum base (tasteless) approximately 20 min after ingesting the 124I-containing capsule in the course of the first day. Absorbed doses per administered 131I activity to the salivary glands were calculated and compared with the previously published results of the lemon-juice stimulation and non-stimulation groups.ResultsThe sonograms in the three test persons showed that glandular blood perfusion by lemon-juice stimulation was clearly increased compared with non-stimulation or chewing of gum base. The sonogram comparison between the chewing-gum stimulation and non-stimulation demonstrated a minor increase of blood flow for the gum base-stimulated salivary glands. The mean ± standard deviation of the absorbed dose per activity under chewing-gum stimulation for the submandibular and parotid glands (within parentheses) was 0.22 ± 0.09 Gy/GBq (0.22 ± 0.08 Gy/GBq). Compared with the absorbed doses of the non-stimulation group, 0.24 ± 0.08 Gy/GBq (0.21 ± 0.05 Gy/GBq), those of the chewing-gum stimulation group showed no significant change (P > 0.60), but the absorbed doses of the lemon-juice stimulation group, 0.35 ± 0.14 Gy/GBq (0.33 ± 0.09 Gy/GBq), were significantly higher (P < 0.04) than those of the chewing-gum stimulation group.ConclusionsThe results suggest that salivary flow induced by chewing gum base does not cause a significant reduction of the salivary gland absorbed dose compared with that in the non-stimulation group. The increased blood flow appears to be a decisive factor causing the increased 131I absorbed doses in the lemon-juice stimulation group.

The influence of saliva flow stimulation on the absorbed radiation dose to the salivary glands during radioiodine therapy of thyroid cancer using 124I PET(/CT) imaging

A serious side effect of high-activity radioiodine therapy in the treatment of differentiated thyroid cancer is radiogenic salivary gland damage. This damage may be diminished by lemon-juice-induced saliva flow immediately after 131I administration. The aim of this study was to assess the effect of chewing lemon slices on the absorbed (radiation) doses to the salivary glands. Ten patients received (pretherapy) 124I PET(/CT) dosimetry before their first radioiodine therapy. The patients underwent a series of six PET scans at 0.5, 1, 2, 4, 48 and ≥96 h and one PET/CT scan at 24 h after administration of 27 MBq 124I. Blood samples were also collected at about 2, 4, 24, 48, and 96 h. Contrary to the standard radioiodine therapy protocol, the patients were not stimulated with lemon juice. Specifically, the patients chewed no lemon slices during the pretherapy procedure and neither ate food nor drank fluids until after completion of the last PET scan on the first day. Organ absorbed doses per administered 131I activity (ODpAs) as well as gland and blood uptake curves were determined and compared with published data from a control patient group, i.e. stimulated per the standard radioiodine therapy protocol. The calculations for both groups used the same methodology. A within-group comparison showed that the mean ODpA for the submandibular glands was not significantly different from that for the parotid glands. An intergroup comparison showed that the mean ODpA in the nonstimulation group averaged over both gland types was reduced by 28% compared to the mean ODpA in the stimulation group (p=0.01). Within each gland type, the mean ODpA reductions in the nonstimulation group were statistically significant for the parotid glands (p=0.03) but not for the submandibular glands (p=0.23). The observed ODpAs were higher in the stimulation group because of increased initial gland uptake rather than group differences in blood kinetics. The 124I PET(/CT) salivary gland dosimetry indicated that lemon juice stimulation shortly after 131I administration in radioiodine therapy increases the absorbed doses to the salivary glands.

Comparative Ultrasonographic, Magnetic Resonance Sialographic, and Videoendoscopic Assessment of Salivary Duct Disorders

Salivary duct disorders are the second most common cause of obstruction after calculi. Magnetic resonance sialography has been recently proposed as a means of diagnosing a heterogeneous group of salivary disorders, and so we compared it with sialoendoscopy in evaluating stenoses and sialectasia in 24 patients with obstructive symptoms and ultrasonographic results negative for calculi or masses. All of the patients (19 of whom had recurrent unilateral or bilateral swollen parotid glands and 5 of whom also had recurrent swollen submandibular glands) underwent dynamic color Doppler ultrasonography and dynamic magnetic resonance sialography with lemon juice stimulation of saliva; 18 patients also underwent diagnostic sialoendoscopy. Ultrasonography and color Doppler ultrasonography showed duct dilatation in all patients (bilateral in 5 with parotid stenosis). Magnetic resonance sialography confirmed duct dilatation and stenosis in all of the patients, and revealed the simultaneous presence of calculi in 4 cases. A parotid sialocele was found in 4 cases. The magnetic resonance sialographic findings were confirmed in the patients who underwent sialoendoscopy. No side effects were observed. Magnetic resonance sialography following prediagnostic ultrasonography allows an adequate diagnosis of salivary duct disorders such as stenosis and sialectasia, as confirmed by objective sialoendoscopic assessment. Magnetic resonance sialography also makes it possible to visualize the salivary duct system up to its tertiary branches and, in this regard, may be considered a valid, noninvasive method for the evaluation of salivary duct disorders.

Normal values of [99mTc]pertechnetate uptake and excretion fraction by major salivary glands

The assessment of the functional status of the salivary glands has been used in the scintigraphic evaluation of xerostomia. Several quantitative methods derived from standard dynamic scintigraphy have been suggested. However, the indices proposed are quite variable and unlikely to be useful in clinical practice. The objectives of this study were to obtain reference values of major salivary glands uptake and excretion fraction in healthy subjects and to obtain normal ratios of Tc-pertechnetate uptake by the major salivary glands in comparison to the thyroid gland uptake. The standardization of these values has the purpose of making this evaluation faster and more objective. Fifty volunteers without clinical evidence of xerostomia or thyroid disease underwent static salivary glands scintigraphy with Tc-pertechnetate. Static images were obtained at 20 minutes and then at 3 minutes after oral stimulation with lemon juice. Percent uptake, excretion fraction and salivary gland to thyroid ratio rates were calculated for the parotid and the submandibular glands. The mean of the uptake values at 20 minutes for the right and left parotid glands were respectively 0.31% and 0.26%, and for the submandibular glands 0.15%. The excretion fraction of the tracer after the lemon juice stimulation was 70% for the parotids glands, 50% for the right and 49% for the left submandibular glands. The mean+/-SD salivary gland to thyroid count ratio was 0.79+/-0.45 for the right parotid, 0.78+/-0.5 for the left parotid, 0.67+/-0.33 and 0.66+/-0.34 for the right and left submandibular glands, respectively. Salivary glands scintigraphy with uptake and excretion fraction calculation is an easy to perform, non-invasive and objective method to investigate salivary glands function. These findings help the nuclear physician to interpret salivary gland scintigraphy more objectively, even in patients with thyroid gland dysfunction in whom Tc-pertechnetate thyroid uptake may be abnormal.

Identification of Warthin Tumor

The aim of this study was to evaluate the accuracy of technetium-99m (Tc-99m) pertechnetate scintigraphy and magnetic resonance (MR) imaging in the diagnosis of Warthin tumor. Sixteen cases of Warthin tumor and 17 cases of non-Warthin tumor were examined by Tc-99m pertechnetate scintigraphy with lemon juice stimulation and MR imaging, including T1-weighted, T2-weighted, short inversion time inversion recovery, diffusion-weighted, and contrast-enhanced dynamic images. We used the receiver operating characteristic (ROC) curve to evaluate diagnostic accuracy. The mean area under the ROC curves of MR imaging in the diagnosis of Warthin tumor (0.97) was higher than that of Tc-99m pertechnetate scintigraphy (0.88). Magnetic resonance imaging is more useful in the evaluation of Warthin tumor than Tc-99m pertechnetate scintigraphy.

Ultrasonography and colour doppler sonography of salivary glands in primary Sjögren's syndrome.

To examine either the ultrasonographic (US) features of the parotids and submandibular glands or the blood flow alterations that may occur in the salivary glands of patients with primary Sjögren's syndrome (pSS) we studied 30 female patients with pSS and 30 controls suffering from dry mouth not due to pSS. All measurements were taken by the same examiner, who used the same equipment to avoid interobserver variability. The US parameters recorded (parenchymal homogeneity, echogenicity, size of the glands and posterior glandular border) were scored according to a previously described scoring system. For each waveform, peak systolic velocity (PSV) and resistive index (RI) were measured at the external carotid artery in the examination of the parotids and at the facial artery within the submandibular glands before and during lemon juice stimulation. On the basis of the degree of chronic inflammatory changes at minor salivary gland (MSG) biopsy, chronic sialadenitis (CS) was defined as mild in 10 and severe in 20 pSS patients. Abnormal US scores were obtained in 26/30 (86.6%) pSS patients and in 9/30 (30%) controls. Moreover, in pSS patients the US scores were sigificantly higher than in the control group (p=-0.0001). The mean (+/- SD) difference between the PSV values taken from parotids and submandibular glands before and during lemon juice stimulation was statistically significant (p=0.003 and p=0.01, respectively) in the controls. On the other hand, no significant changes in the PSV values were found in the whole group of pSS patients. However, the changes in PSV values before and during lemon juice stimulation were statistically significant in both parotids (p=0.019) and submandibular glands (p=0.012), and not significantly different from those in the controls in pSS patients with mild CS. The variability of RI taken from the salivary glands before and during lemon juice stimulation was not statistically significant in either pSS patients or controls. US abnormalities were detected in the majority of pSS patients and their severity was significantly greater than those recorded in the controls. Of the colour Doppler sonographic (CDS) parameters only PSV was influenced by the degree of chronic inflammation, as shown at the MSG biopsy, suggesting that PSV may reflect the vascular changes occurring in the salivary glands during the course of an autoimmune disease such as pSS.

Warthin's tumor of parotid gland on Tc-99m pertechnetate scintigraphy with lemon juice stimulation: Tc-99m uptake, size, and pathologic correlation.

The aim of this study was to evaluate the usefulness of technetium-99m (Tc-99m) pertechnetate scintigraphy with lemon juice stimulation in the diagnosis of Warthin's tumor and its correlation with Tc-99m uptake, tumor size, and histologic subtype. Tc-99m pertechnetate scintigraphy before and after lemon juice stimulation and pathologic specimens of 34 Warthin's tumors and 47 non-Warthin's lesions were retrospectively evaluated. Tc-99m uptake of Warthin's tumors before and after stimulation was visually graded as follows: absent; indeterminate; low grade; definite; and strong. Tumor size was defined as maximum diameter of the tumor measured from the surgical specimen. Warthin's tumors were classified into three histologic subtypes according to the ratio of epithelial and lymphoid stromal components: predominant epithelial; intermediate; and low-grade epithelial types. Eighteen of 34 (53%) Warthin's tumors and one benign lymphoepithelial cyst showed higher uptake than that of the normal parotid gland on Tc-99m scintigraphy before lemon juice stimulation. Thirty-two of the 34 (94%) Warthin's tumors, one benign lymphoepithelial cyst, one pleomorphic adenoma, and one oncocytoma revealed higher uptake than that of the normal parotid gland on Tc-99m scintigraphy after lemon juice stimulation. The mean size was 37 mm in strong uptake Warthin's tumors, 24 mm in definite uptake tumors, 19 mm in low-grade uptake tumors, and 12 mm in low-grade uptake tumors excluding those tumors with large cystic component. There was a significant correlation between tumor size and degree of Tc-99m uptake after lemon juice stimulation. However, there was no correlation between histologic subtype and Tc-99m uptake, and histologic subtype and tumor size in Warthin's tumors. Our study concludes that Tc-99m pertechnetate scintigraphy with lemon juice stimulation is useful for the detection and diagnosis of Warthin's tumor. The degree of uptake in Warthin's tumor on Tc-99m scintigraphy with lemon juice stimulation depends mainly on tumor size and the presence of large cystic component in it.

Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine.

Is salivary flow related to personality?

Studies conducted in the 1960s proposed that stimulated salivary flow was negatively correlated with the personality trait of introversion-extraversion such that introverted individuals were supposed to salivate more strongly to lemon-juice stimulation than were extraverts. The relationship was re-examined in the present study in light of more recent but inconsistent findings. A sample of 36 male and female volunteers showed no significant relationship between stimulated salivary flow and extraversion. Nor was flow related to State or Trait anxiety according to Spielberger's anxiety inventory, or to CNS activation as assessed by an objective electronic test. It was concluded that there was no evidence to relate stimulated salivary flow rates to personality in volunteers selected from a non-psychiatric population.

Effects of parathyroid hormone on total protein, calcium, magnesium, phosphorus, sodium and potassium concentrations of normal human parotid saliva*

The effects of parathyroid hormone (PTH) administered to six young normal adult subjects on protein, calcium, magnesium, phosphorus, sodium and potassium concentrations in parotid saliva have been studied in relation to the salivary flow rate. Stensen's duct was cannulated and excretion patterns of the constituents determined before and after stimulation of saliva production by lemon juice. After a control period (period 1), 50 U of PTH were given i.v. followed by an infusion of 2 U/min for 60-90 min (period 2). In the absence of any detectable changes in plasma, PTH induced a significant rise of salivary protein, calcium, and phosphorus concentrations at rest and following lemon juice stimulation, and of sodium concentration, but only at high flow rates for the latter. PTH did not change magnesium and potassium excretions significantly. Control experiments without PTH were performed on five other subjects. Protein, phosphorus and potassium concentrations did not change significantly between period 1 and period 2. Calcium and sodium excretions were reduced and magnesium excretion increased during period 2. These results provide evidence that PTH acts on the parotid gland by affecting protein secretion and electrolyte transport. Possible mechanisms of these changes are discussed.

Short- and long-term memory as a function of individual differences in arousal.

In a paired-associate learning experiment employing 40 university students as Ss, the contribution of individual differences in arousal to short-and long-term retention was investigated using individual differences in salivary response to lemon juice stimulation as an index of arousal. Experimental Ss were pre-selected from 99 Ss on the basis of extreme arousal scores. The hypotheses were confirmed; low-arousal recall is greater than high-arousal recall on a test of short-term retention ( p &lt; .08) and high-arousal recall is greater than low-arousal recall on a test of long-term retention ( p &lt; .04).

Salivary response to lemon juice as a measure of introversion in children.

The relationship between introversion, as measured by the Junior Eysenck Personality Inventory, and salivation to lemon juice was examined with 10 boys and 10 girls at CA 8, 10, and 12. Boys salivated significantly more than girls to lemon juice stimulation ( P &lt; .05), but comparable sex differences also occurred in salivation to water by control Ss. Introversion correlated .43 ( P &lt; .01) with salivation for all 25 girls but not for boys (r = .19). Ss who were in the upper third of the total group on extraversion showed significantly less salivation to lemon juice than did Ss in the lower third ( P &lt; .025), which is consistent with Eysenck's theoretical analysis.