Is oropharyngoesophageal scintigraphy the method of choice for assessing dysphagia in systemic sclerosis? A single center experience.

OBJECTIVES: To evaluate the performance of oropharyngoesophageal scintigraphy (OPES) in the assessment of dysphagia in patients with systemic sclerosis (SSc), and to compare OPES results with those of barium esophagogram. METHODS: Adult SSc patients who underwent OPES for the assessment of dysphagia were enrolled. OPES was performed with both liquid and semisolid boluses and provided information regarding oropharyngeal transit time, esophageal transit time (ETT), oropharyngeal retention index (OPRI), esophageal retention index (ERI), and site of bolus retention. Barium esophagogram results were also collected. RESULTS: Fifty-seven SSc patients (87.7% female, mean age 57.7 years) with dysphagia were enrolled. OPES identified at least one alteration in each patient and findings were generally worse for the semisolid bolus. Esophageal motility was widely impaired with 89.5% of patients with an increased semisolid ERI, and middle-lower esophagus was the most frequent site of bolus retention. However, oropharyngeal impairment was highlighted by widespread increased OPRI, especially in anti-topoisomerase I positivity. Older patients and with longer disease duration presented slower semisolid ETT (p = 0.029 and p = 0.002, respectively). Eleven patients with dysphagia had a negative barium esophagogram: all of them presented some alterations in OPES parameters. CONCLUSION: OPES revealed a marked SSc esophageal impairment, in terms of both slowed transit time and increased bolus retention, but also shed light on oropharyngeal swallowing alterations. OPES showed high sensitivity, being able to detect swallowing alterations in dysphagic patients with negative barium esophagogram. Therefore, the use of OPES for the assessment of SSc-related dysphagia in clinical practice should be promoted.

Neuroendocrine markers and psychological features in patients with irritable bowel syndrome.

BACKGROUND AND AIMS: The key role of the brain-gut axis in the pathophysiology of irritable bowel syndrome (IBS) has been recognized. The aim of this study was to assess the possible association between IBS, neuroendocrine markers, and psychological features. METHODS: One hundred and twenty-five consecutive IBS patients and 105 healthy subjects were enrolled. Plasma serotonin, plasma and urinary cortisol, and plasma neuropeptide Y levels were evaluated. All patients were given a questionnaire to assess IBS symptom severity. In 66 patients, a psychodiagnostic assessment was carried out. RESULTS: A high incidence of specific psychological features, including state anxiety (69.69 %), trait anxiety (54.54 %), obsessions and compulsions (28.78 %), was observed in IBS patients. A positive correlation between neuropeptide Y and state anxiety (r = 0.287, p = 0.024) and simulation/social ingenuity (r = 0.269, p = 0.039) was found in these patients. In diarrhea-predominant IBS, plasma cortisol was linearly related to plasma serotonin (r = 0.5663, p < 0.001). CONCLUSIONS: In IBS patients, a significant correlation was found between specific psychological features and neuroendocrine markers, especially plasma cortisol and neuropeptide Y; in diarrhea-predominant IBS, a correlation between plasma cortisol and serotonin was found, although it needs to be confirmed in more extensive cohorts.

Primary hyperparathyroidism: fifth parathyroid intrathymic adenoma in a young patient.

The clinical case described in this paper deals with a young female patient affected by primary hyperparathyroidism caused by an ectopic parathyroid adenoma of a supernumerary intrathymic parathyroid. The patient had hypercalcemia, in association with increased levels of parathormone, but was otherwise asymptomatic. Genetics tests for mutation of the MEN1, HRPT2, and CaSR genes were negative. She therefore underwent laboratory and instrumental tests but localization results in the neck were negative--only an intrathymic nodule was visualized. The complete surgical ablation of the thymus was conducted, which highlighted a nodule that, at histological examination, was shown to be an adenoma of a fifth parathyroid gland. The existence of a fifth, hyperfunctioning, intrathoracic parathyroid appears to be a rare cause of primary juvenile sporadic hyperparathyroidism. This peculiar clinical case could be of interest in similar cases evaluated by other surgeons.

Current role of 111In-DTPA-octreotide scintigraphy in diagnosis of thymic masses.

AIMS AND BACKGROUND: Thymic tumors (thymomas and thymic carcinomas) represent 50% of all mediastinal tumors. Thymomas usually express high levels of somatostatin receptors, which enable in vivo imaging with 111In-DTPA-octreotide (OctreoScan®). The aim of this study was to further investigate the role of radionuclide techniques in the diagnosis, staging and follow-up of these tumors. METHODS: Eight patients (5 women, 3 men, age range 35-79 years; mean ± SD 56.1 ± 15.8 years) entered the study. In 4 patients, myasthenia gravis was the presenting symptom. 111In-DTPA-octreotide scan was performed within 3 weeks after contrast enhanced CT and/or MRI. Planar and tomographic images were acquired within 24 hours of the injection of 111 MBq OctreoScan. The scintigraphic results were defined in correlation with the histological findings. RESULTS: Histology revealed thymoma in 3 patients, thymic carcinoma in 1, insular carcinoma of presumably thymic origin in 1, thymic carcinoid in 1, and thymic hyperplasia in 2 patients. Two thymomas were at stage I, 1 thymoma and 1 thymic carcinoma at stage II, 1 insular carcinoma of presumably thymic origin at stage IV, and 1 thymic carcinoid at stage IV. OctreoScan consistently accumulated in primary and/or metastatic sites of thymic tumors while no radiotracer uptake was detected in the 2 patients with benign thymic hyperplasia. In 1 patient with a very large mediastinal mass (13 cm in largest diameter) and multiple metastatic deposits in the lungs, OctreoScan scintigraphy showed a large area of pathological uptake in the anterior mediastinum and a small area of focal uptake in the cervical-dorsal region of the right lung corresponding to a lymph node expressing somatostatin receptors. CONCLUSIONS: OctreoScan is avidly taken up by thymic tumors, enabling the diagnosis of these tumors and a better evaluation of their extension. It does not accumulate in thymic hyperplasia, thus allowing the differential diagnosis between these 2 pathological conditions. In patients affected by myasthenia gravis, OctreoScan scintigraphy can play an important role in characterizing thymic masses.

The Role of Nuclear Medicine in the Clinical Management of Benign Thyroid Disorders, Part 1: Hyperthyroidism.

Benign thyroid disorders, especially hyper- and hypothyroidism, are the most prevalent endocrine disorders. The most common etiologies of hyperthyroidism are autoimmune hyperthyroidism (Graves disease, GD), toxic multinodular goiter (TMNG), and toxic thyroid adenoma (TA). Less common etiologies include destructive thyroiditis (e.g., amiodarone-induced thyroid dysfunction) and factitious hyperthyroidism. GD is caused by autoantibodies against the thyroid-stimulating hormone (TSH) receptor. TMNG and TA are caused by a somatic activating gain-of-function mutation. Typical laboratory findings in patients with hyperthyroidism are low TSH, elevated free-thyroxine and free-triiodothyronine levels, and TSH-receptor autoantibodies in patients with GD. Ultrasound imaging is used to determine the size and vascularity of the thyroid gland and the location, size, number, and characteristics of thyroid nodules. Combined with lab tests, these features constitute the first-line diagnostic approach to distinguishing different forms of hyperthyroidism. Thyroid scintigraphy with either radioiodine or 99mTc-pertechnetate is useful to characterize different forms of hyperthyroidism and provides information for planning radioiodine therapy. There are specific scintigraphic patterns for GD, TMNG, TA, and destructive thyroiditis. Scintigraphy with 99mTc-sestamibi allows differentiation of type 1 from type 2 amiodarone-induced hyperthyroidism. The radioiodine uptake test provides information for planning radioiodine therapy of hyperthyroidism. Hyperthyroidism can be treated with oral antithyroid drugs, surgical thyroidectomy, or 131I-iodide. Radioiodine therapy is generally considered after failure of treatment with antithyroid drugs, or when surgery is contraindicated or refused by the patient. In patients with TA or TMNG, the goal of radioiodine therapy is to achieve euthyroid status. In GD, the goal of radioiodine therapy is to induce hypothyroidism, a status that is readily treatable with oral thyroid hormone replacement therapy. Dosimetric estimates based on the thyroid volume to be treated and on radioiodine uptake should guide selection of the 131I-activity to be administered. Early side effects of radioiodine therapy (typically mild pain in the thyroid) can be handled by nonsteroidal antiinflammatory drugs. Delayed side effects after radioiodine therapy for hyperthyroidism are hypothyroidism and a minimal risk of radiation-induced malignancies.

The Role of Nuclear Medicine in the Clinical Management of Benign Thyroid Disorders, Part 2: Nodular Goiter, Hypothyroidism, and Subacute Thyroiditis.

Part 2 of this series of Continuing Education articles on benign thyroid disorders deals with nodular goiter, hypothyroidism, and subacute thyroiditis. Together with Part 1 (which dealt with various forms of hyperthyroidism), this article is intended to provide relevant information for specialists in nuclear medicine dealing with the clinical management of patients with benign thyroid disorders, the primary audience for this series. Goiter, an enlargement of the thyroid gland, is a common endocrine abnormality. Constitutional factors, genetic abnormalities, or dietary and environmental factors may contribute to the development of nodular goiter. Most patients with nontoxic nodular goiter are asymptomatic or have only mild mechanical symptoms (globus pharyngis). Work-up of these patients includes measurement of thyroid-stimulating hormone, free triiodothyronine, free thyroxine, thyroid autoantibodies, ultrasound imaging, thyroid scintigraphy, and fine-needle aspiration biopsy of nodules with certain ultrasound and scintigraphic features. Treatment for multinodular goiter includes dietary iodine supplementation, surgery, radioiodine therapy (to decrease thyroid size), and minimally invasive ablation techniques. Hypothyroidism ranges from rare cases of myxedema to more common mild forms (subclinical hypothyroidism). Primary hypothyroidism often has an autoimmune etiology. Clinical presentations differ in neonates, children, adults, and elderly patients. Work-up includes thyroid function tests and ultrasound imaging. Nuclear medicine is primarily used to locate ectopic thyroid tissue in congenital hypothyroidism or to detect defects in iodine organification with the perchlorate discharge test. Treatment consists of thyroid replacement therapy with l-thyroxine, adjusting the daily dose to the individual patient's metabolic and hormonal requirements. Subacute thyroiditis is a self-limited inflammatory disorder of the thyroid gland, often associated with painless or painful swelling of the gland and somatic signs or symptoms. Inflammation disrupts thyroid follicles resulting in a rapid release of stored thyroxine and triiodothyronine causing an initial thyrotoxic phase, often followed by transient or permanent hypothyroidism. Although subacute thyroiditis is often related to a viral infection, no infective agent has been identified. Subacute thyroiditis may be caused by a viral infection in genetically predisposed individuals. Work-up includes lab tests, ultrasound imaging, and radionuclide imaging. Thyroid scintigraphy demonstrates different findings depending on the phase of the illness, ranging from very low or absent tracer uptake in the thyroid gland in the hyperthyroid phase to a normal appearance in the late recovery phase. Since subacute thyroiditis is self-limited, treatment is directed toward relief of pain. High-dose nonsteroidal antiinflammatory drugs are usually the first-line treatment. If severe pain persists, a course of corticosteroids may be necessary. Permanent hypothyroidism develops in up to 15% of patients with subacute thyroiditis, even more than 1 y after presentation.

Recombinant human TSH and ablation of post-surgical thyroid remnants in differentiated thyroid cancer: the effect of pre-treatment with furosemide and furosemide plus lithium.

BACKGROUND AND AIM: Recombinant human TSH (rhTSH) can be used for post-surgical radioiodine (I-131) thyroid remnants ablation in differentiated thyroid cancer (DTC) patients after surgery. Debate exists in literature about the optimal amount of I-131 that should be given for obtaining an effective ablation and about the role of iodine pool during treatment. Therefore, the aim of the present study was to assess whether I-131 ablation during rhTSH stimulus can be improved by reducing the circulating iodine pool and by increasing thyroid cell uptake and retention of I-131 obtained by administering furosemide and lithium. METHODS: A total of 201 consecutive DTC patients were entered in the study: they were treated by total thyroidectomy and I-131 therapy during rhTSH stimulus to ablate thyroid remnants. Patients were divided into two groups according to the TNM stage: group 1 included patients in stage I-II who were treated with a low 30-mCi I-131 dose, while group 2 included patients in stage III-IV who were treated by a high 100-mCi I-131 dose. Moreover, both groups were further subdivided into three subgroups. Subgroup (a) included 45 patients from group 1 and 22 from group 2: they were treated with I-131 under rhTSH stimulus, following a short 4-day withdrawal of L-thyroxine (LT4). Subgroup (b) included 45 patients from group 1 and 22 from group 2: they were treated with I-131 under rhTSH stimulus, following a short 4-day withdrawal of L-T4, and after furosemide administration (25 mg/day orally) during the 3 days before I-131. Subgroup (c) included 45 patients from group 1 and 22 from group 2: they were treated with I-131 under rhTSH stimulus, following a short 4-day L-T4 withdrawal, and after administration of furosemide (25 mg/day orally) during the 3 days prior I-131 and lithium (450 mg/day orally) during the 3 days following I-131. Another group (group 3) of 20 patients characterized by a very low-risk cancer (unifocal tumor <1.0 cm in diameter, without extra-capsular extension, N0) was treated with a 30-mCi I-131 dose under rhTSH stimulus without performing the short 4-day L-4 withdrawal: this group was taken as the control. Follow-up was performed by neck ultrasonography (US), and Tg measurement and I-131 WBS under rhTSH stimulus. RESULTS: Among the patients from group 1, those pre-treated with furosemide or with furosemide plus lithium showed a better outcome of ablation both in terms of undetectable Tg values (97.7% and 95.5 % vs. 79.5%, p < 0.05) and of WBS negativity (97.7% vs. 81.8%, p < 0.05) during the rhTSH stimulus. No similar findings were observed in group 2 patients. Moreover, in patients from group 3 (I-131 30 mCi, without L-T4 withdrawal), the outcome of ablation was significantly lower in comparison to patients from group 1 (I-131 30 mCi, with L-T4 withdrawal) in terms of undetectable Tg during the rhTSH stimulus (55.0%, p < 0.001). CONCLUSION: rhTSH is highly effective for post-surgical thyroid remnant ablation in low-risk cancer patients using the low 30-mCi dose protocol combined with the short 4-day withdrawal of L-T4. Moreover, in these patients the pre-treatment with furosemide seems to play an important role to further improve the outcome of ablation by reducing the iodine pool.

Thyroid uptake of 67Ga-citrate is associated with thyroid autoimmunity and hypothyroidism in patients with sarcoidosis.

PURPOSE: To evaluate the association of gallium-67 ((67)Ga)-citrate thyroid uptake with the presence of thyroid disorders in patients with sarcoidosis (S patients). METHODS: Eighty-four S patients were evaluated by a complete thyroid work-up (neck ultrasound, circulating thyroid hormones and anti-thyroid antibodies, fine-needle aspiration). RESULTS: In S patients with (67)Ga thyroid uptake (respect those without): serum thyroid-stimulating hormone, the titre of anti-thyroid peroxidase (AbTPO) and/or anti-thyroglobulin antibodies (AbTg), and the prevalence of S patients with hypothyroidism or with positive AbTg or AbTPO was significantly higher; a thyroid hypoechoic pattern was more frequent. The prevalence of thyroid nodules was not significantly different between the two groups. Two cases of papillary thyroid cancer were observed in S patients without (67)Ga thyroid uptake, whilst no case in those with (67)Ga thyroid uptake. CONCLUSIONS: (67)Ga thyroid uptake is associated with the presence of aggressive autoimmune thyroiditis and hypothyroidism in S patients; thyroid function and ultrasonography should be performed in the presence of (67)Ga thyroid uptake.

Assessment of swallowing function with oro-pharyngeal-esophageal scintigraphy in patients with idiopathic inflammatory myopathies.

BACKGROUND: Swallowing impairment is frequently present in patients with idiopathic inflammatory myopathies (IIMs), and it represents an important cause of morbidity, dramatically reducing the quality of life of patients. Moreover, dysphagia is associated to a worst prognosis. Unfortunately, no standardized instrumental techniques for the assessment of the upper gastrointestinal tract in IIM patients are available. In this study, we explored the characteristics of the alterations in the upper gastrointestinal tract using oro-pharyngeal-esophageal scintigraphy (OPES) in a cohort of IIM patients and we correlated the alterations with clinical parameters. METHODS: A total of 51 IIM patients were examined with OPES, both with liquids and semisolids, and the data acquired were examined to compute the transit time and the percentage of retention at oral, pharyngeal, and esophageal level. Patient-reported outcome data (PRO) on dysphagia, disease activity, and clinical parameters were collected. KEY RESULTS: Oro-pharyngeal-esophageal scintigraphy identified at least one alteration in all patients, particularly with the semisolid test and oral and pharyngeal levels presented a higher frequency of involvement compared to the esophageal tract (P < 0.05). A very good correlation between dysphagia severity assessed by PRO and many OPES results was identified. In patients with a shorter disease duration, there was a higher prevalence of alterations at the oral and pharyngeal level and they were correlated to higher swallowing difficulties and higher disease activity parameters. CONCLUSIONS & INFERENCES: Our results showed that OPES may represent a novel reproducible tool to assess dysphagia in IIM patients, thus opening new possibilities to evaluate dysphagia in these patients.

Radionuclide evaluation of the lower gastrointestinal tract.

This review outlines the technical aspects and diagnostic performance parameters of nuclear medicine procedures used on patients with disorders of the lower gastrointestinal tract, with the exclusion of techniques using tumor-seeking radiopharmaceuticals. Chronic disorders of the lower gastrointestinal tract often reduce the quality of life because of discomfort from constipation or diarrhea. Five classes of radionuclide procedures are used to characterize these disorders: transit scintigraphy, searches for ectopic gastric mucosa in Meckel's diverticulum, scintigraphy of active inflammatory bowel disease, scintigraphic defecography, and scintigraphy to detect sites of gastrointestinal bleeding. Protocols for these procedures and their relative merit in patient management are discussed, with special emphasis on their potential for semiquantitative assessment of the pathophysiologic parameter investigated. Quantitation is particularly relevant for prognostic purposes and for monitoring the efficacy of therapy.

Detection of bilateral, multifocal breast cancer and assessment of tumour response to neoadjuvant chemotherapy by Tc-99m sestamibi imaging - a case report.

In breast cancer, neoadjuvant chemotherapy needs early indication for responsiveness. Tc-99m sestamibi scintimammography provides comprehensive information about the extent of disease including multiple foci in one or both breasts and possible involvement of nodes. In the present case, X-mammography was positive for a suspicious mass in the upper quadrant of the left breast only. On the other hand,Tc-99m Sestamibi scintimammography was able to depict the full extent of the disease, including its spread to the axillary lymph node, and gave useful information on the effectiveness of neoadjuvant chemotherapy. The case reported here demonstrates that Tc-99m sestamibi scintimammography was useful in detecting bilateral breast cancer and could provide additional information on possible axillary lymph node involvement. Furthermore, Tc-99m sestamibi scintimammography was effective in monitoring response to chemotherapy in the studied case.

Iodine-131 given for therapeutic purposes modulates differently interferon-gamma-inducible alpha-chemokine CXCL10 serum levels in patients with active Graves' disease or toxic nodular goiter.

CONTEXT: The mechanism of activation of the immune system after iodine-131 (131I) treatment of hyperthyroidism is still not fully clarified. Serum levels of CXCL10, a prototype of the CXC family of chemokines, are increased in several endocrine autoimmune conditions, and this chemokine plays a role at least in the initial phases of thyroid autoimmune disease and in Graves' disease (GD). OBJECTIVE, DESIGN, AND PATIENTS: The aim of the present study was to measure the serum CXCL10 levels in 20 patients with GD and 10 patients with toxic nodular goiter (TNG) before and 6 months after 131I treatment, when patients had achieved euthyroidism. Forty healthy subjects and 40 patients with autoimmune thyroiditis served as control groups. RESULTS: Before 131I, mean CXCL10 was significantly higher in patients with GD and thyroiditis than controls or those with TNG. Serum CXCL10 levels significantly decreased in GD patients 6 months after 131I treatment, whereas they remained within normal limits in TNG patients after restoration of euthyroidism by 131I. CONCLUSIONS: In conclusion, our results demonstrate that high serum CXCL10 levels are associated with the hyperthyroid phase in GD but not TNG, providing further evidence for a minimal role of hyperthyroidism per se in determining high CXCL10 levels and showing a strong association with the autoimmune process. The reduction of CXCL10 levels after 131I treatment in GD only shows that the thyroid gland itself is the main source of circulating CXCL10.

Comparison between remnant and red-marrow absorbed dose in thyroid cancer patients submitted to 131I ablative therapy after rh-TSH stimulation versus hypothyroidism induced by L-thyroxine withdrawal.

OBJECTIVE: In thyroidectomized patients, increased levels of thyroid stimulating hormone (TSH) are necessary to maximize I uptake. Traditionally, this has been achieved by withdrawing L-thyroxine (L-T4) for 4-6 weeks, inducing hypothyroidism in patients. The availability of a genetically engineered version of the recombinant human TSH (rh-TSH) provides an alternative tool to enhance the TSH serum level without inducing hypothyroidism. In this paper the I remnant and red-marrow doses calculated in differentiated thyroid cancer (DTC) patients pre-treated with rh-TSH are compared to those calculated in patients in hypothyroidism induced by L-T4 withdrawal. METHODS: Forty-six DTC patients, submitted to I ablative therapy, were randomly divided in group A (pre-treated with rh-TSH) and group B (treated after L-T4 withdrawal for 30 days). The red-marrow absorbed dose per unit administered activity and the remnant cumulated activity per unit administered activity were calculated for both groups. RESULTS: The red-marrow dose in 17 rh-TSH treated patients is 0.06+/-0.02 mGy.MBq; that in 14 hypothyroid patients is 0.09+/-0.03 mGy.MBq (two-tailed unpaired t-test P=0.003). The remnant cumulated activity per unit administered activity in 10 rh-TSH treated patients is 0.9+/-0.8 h; that calculated in 21 hypothyroid patients is 1.55+/-1.05 h (two-tailed unpaired t-test P=0.063). This last result is mainly due to the difference between the maximum uptake (U) in rh-TSH (U=0.01+/-0.01) and hypothyroid patients (U=0.03+/-0.02) (two-tailed unpaired t-test P=0.019). CONCLUSION: The rh-TSH pre-treated patients seem to have a lower uptake compared to those in hypothyroidism induced by L-T4 withdrawal. On the other hand their red-marrow absorbed dose seems to be lower.

Increased serum CXCL10 in Graves' disease or autoimmune thyroiditis is not associated with hyper- or hypothyroidism per se, but is specifically sustained by the autoimmune, inflammatory process.

OBJECTIVE: Serum CXCL10 (an interferon-gamma-inducible chemokine) levels (sCXCL10) are increased in several autoimmune conditions, including Graves' disease (GD) and autoimmune thyroiditis (AT). Longitudinal assessment of sCXCL10 in autoimmune hypo- or hyperthyroidism has not yet been performed. DESIGN AND METHODS: We longitudinally assayed sCXCL10 in the following groups: thirty-three GD and 11 toxic nodular goiter (TNG) patients when hyperthyroid (Hyper) and when reaching euthyroidism (Eu) with methimazole therapy (MMI) sixty-six AT (33 hypothyroid (Hypo) and 33 Eu) patients, basally and after reaching EU (for Hypo) with levothyroxine (L-T4) therapy twenty-two patients with thyroid cancer (CA) under L-T4-suppressive treatment, of whom 11 were re-evaluated after L-T4 withdrawal for diagnostic WBS, and 11 after recombinant TSH (rhTSH) administration thirty-three healthy controls. RESULTS: At initial evaluation, Hyper GD and AT (Hypo significantly higher than Eu) showed significantly higher mean sCXCL10 than all other groups. MMI treatment led to a significant decrease in sCXCL10 only in GD (not in TNG), while restoration of Eu, in Hypo AT, by L-T4 was not accompanied by significant sCXCL10 change. CA showed sCXCL10 comparable to controls, and both Hypo after L-T4 withdrawal and rhTSH injection had no effect on sCXCL10. CONCLUSIONS: Treatment of Hyper leads to a significant decrease in sCXCL10 only in GD, and this probably depends upon the MMI immunomodulatory effect. L-T4 correction of Hypo is not accompanied by significant modification of sCXCL10 in AT. Increased sCXCL10 is not associated with Hyper or Hypo per se, but is specifically sustained by the autoimmune inflammatory event occurring in both GD and AT.

A study of the possibility of curing Graves' disease based on the desired reduction of thyroid mass (volume) as a consequence of 131I therapy: a speculative paper.

PURPOSE: The possibility of predicting the final volume of Graves' disease thyroids submitted to 131I therapy could allow the physician to decide what activity to administer based on the desired volume reduction instead of on a fixed value of the thyroid radiation absorbed dose. In this paper the relationship between maximum uptake of 131I, fractional reduction of thyroid volume and outcome of Graves' disease is discussed. METHODS: The results are based on ultrasonography thyroid volume measurements before administration of therapy and at the moment of recovery from Graves' disease (thyroid stimulating hormone >0.3 microIU x ml(-1) in the absence of anti-thyroid drug therapy) and on measurements of 131I uptake in 40 patients. It is shown that the possibility of curing Graves' disease may be individually related to the final volume of the patient's thyroid. An equation is presented to calculate the 'optimal' final thyroid volume. RESULTS: A comparison between the traditional method, based on absorbed dose, and the final method, based on volume, has been carried out retrospectively. In the first case a median activity of 529 MBq has been administered; in the second, a median activity of 394 MBq (non-parametric Wilcoxon test, P<0.05) should be administered. The corresponding thyroid median absorbed doses are, respectively, 353 Gy and 320 Gy (non-parametric Wilcoxon test, P<0.02). CONCLUSION: A method to evaluate individually the 'optimal' final thyroid mass is presented and discussed. The method based on 'volume reduction' could probably reduce the activity and the thyroid absorbed dose compared to the method based on 'empirical' calculations, thus allowing the administration of 131I therapy to be optimized.

Thyroid Ultrasound and Other Imaging Procedures in the Pediatric Age.

The purpose of this review is to provide a reappraisal of the diagnostic imaging procedures for thyroid carcinoma in pediatric patients, including thyroid ultrasound (US), ultrasound-guided fine-needle aspiration biopsy (FNAB), scintigraphy, radiological techniques (CT, MR), and PET/CT. The most frequent indication for thyroid imaging is characterization of a palpable mass in the neck or thyroid gland. Thyroid US is a first-line examination for visualizing the thyroid gland as it provides anatomic and perfusion information; on the other hand, scintigraphy mostly provides functional information but combined with some anatomic information as well. CT and MRI have a supplemental role in these patients. Furthermore, with the introduction of PET/CT and the development of new imaging agents, nuclear medicine plays an important role in different phases of neoplastic disease in terms of both staging and evaluation of response to medical/surgical treatments.

A predictive mathematical model for the calculation of the final mass of Graves' disease thyroids treated with 131I.

Substantial reductions in thyroid volume (up to 70-80%) after radioiodine therapy of Graves' hyperthyroidism are common and have been reported in the literature. A relationship between thyroid volume reduction and outcome of 131I therapy of Graves' disease has been reported by some authors. This important result could be used to decide individually the optimal radioiodine activity A0 (MBq) to administer to the patient, but a predictive model relating the change in gland volume to A0 is required. Recently, a mathematical model of thyroid mass reduction during the clearance phase (30-35 days) after 131I administration to patients with Graves' disease has been published and used as the basis for prescribing the therapeutic thyroid absorbed dose. It is well known that the thyroid volume reduction goes on until 1 year after therapy. In this paper, a mathematical model to predict the final mass of Graves' diseased thyroids submitted to 131I therapy is presented. This model represents a tentative explanation of what occurs macroscopically after the end of the clearance phase of radioiodine in the gland (the so-called second-order effects). It is shown that the final thyroid mass depends on its basal mass, on the radiation dose absorbed by the gland and on a constant value alpha typical of thyroid tissue. Alpha has been evaluated based on a set of measurements made in 15 reference patients affected by Graves' disease and submitted to 131I therapy. A predictive equation for the calculation of the final mass of thyroid is presented. It is based on macroscopic parameters measurable after a diagnostic 131I capsule administration (0.37-1.85 MBq), before giving the therapy. The final mass calculated using this equation is compared to the final mass of thyroid measured 1 year after therapy administration in 22 Graves' diseased patients. The final masses calculated and measured 1 year after therapy are in fairly good agreement (R = 0.81). The possibility, for the physician, to decide a therapeutic activity based on the desired decrease of thyroid mass instead of on a fixed thyroid absorbed dose could be a new opportunity to cure Graves' disease.

The role of 99mTc-tetrofosmin scintigraphy for staging patients with laryngeal cancer.

Diagnosis and staging of laryngeal cancer is currently based on physical examination, endoscopy, and imaging techniques such as computed tomography (CT) and/or magnetic resonance (MR) and histology. While imaging techniques have a pivotal role for defining the size of the primary tumor, they are less accurate for defining metastatic involvement of regional lymph nodes, especially if lymph nodes are smaller than 10-15 mm. The aim of this study was to comparatively assess the relevance of (99m)Tc-tetrofosmin scintigraphy for the staging of laryngeal tumors versus the CT scan. We evaluated the sensitivity of imaging with (99m)Tc-tetrofosmin in 28 consecutively enrolled patients with squamous cell laryngeal carcinoma. Total-body scintigraphy with 99mTc-tetrofosmin was performed preoperatively, and the results were compared to CT images of the neck and mediastinum. CT and (99m)Tc-tetrofosmin scintigraphy were equally sensitive (96%) in identifying the primary tumor. While CT was more sensitive for detecting metastatic lymph nodes (100% versus 50%), (99m)Tc-tetrofosmin scintigraphy was more specific (100% versus 56%; p < 0.04). The overall diagnostic capabilities of the two techniques for detecting lymph node metastases were comparable (Youden Index: J = 0.56 for CT and J = 0.50 for (99m)Tc-tetrofosmin scintigraphy). (99m)Tc-tetrofosmin scintigraphy is a useful complement to CT for staging laryngeal tumors, especially for detecting metastatic lymph nodes and distant metastases.

Comparison of different thyroid committed doses in radioiodine therapy for Graves' hyperthyroidism.

Despite vast worldwide experience in the use of 131I for treating Graves' disease (GD), no consensus of opinion exists concerning the optimal method of dose calculation. In one of the most popular equations, the administered (131)I dose is directly proportional to the estimated thyroid gland volume and inversely proportional to the measured 24-hour radioiodine uptake. In this study, we compared the efficiency of different tissue-absorbed doses to induce euthyroidism or hypothyroidism within 1 year after radioiodine therapy in GD patients. The study was carried out in 134 GD patients (age, 53 +/- 14 year; range, 16-82 year; thyroid volume, 28 +/- 18 mL; range, 6-95 mL; average 24-hour thyroid uptake, 72%) treated with (131)I therapy. The average radioiodine activity administered to patients was 518 +/- 226 MBq (range, 111-1110). The corresponding average thyroid absorbed dose, calculated by a modified Medical Internal Radiation Dose (MIRD) equation was 376 +/- 258 Gy (range, 99-1683). One year after treatment, 58 patients (43%) were hypothyroid, 57 patients (43%) were euthyroid, and 19 patients (14%) remained hyperthyroid. The patients were divided into 3 groups: 150 Gy (n = 32), 300 Gy (n = 58) and >300 Gy (n = 44). No significant difference in the rate of recurrent hyperthyroidism was found among the 3 groups (150 Gy: 15%; 300 Gy: 14%; and > or =300 Gy: 14%; chi-square test, p = 0.72). Whereas, the rate of hypothyroidism in the 3 groups was significantly correlated with the dose (150 Gy: 30%; 300 Gy: 46%; >300 Gy: 71%; chi-square test, p = 0.0003). The results obtained in this study show no correlation between dose and outcome of radioiodine therapy (in terms of persistent hyperthyroidism) for thyroid absorbed doses > or =150 Gy, while confirming the relation between the thyroid absorbed dose and the incidence of hypothyroidism in GD patients.

The Value of Oro-Pharyngo-Esophageal Scintigraphy in the Management of Patients with Aspiration into the Tracheo-bronchial Tree and Consequent Dysphagia.

CONTEXT: Tracheo-bronchial aspiration is the most invalidating condition which can happen to patients affected by dysphagia, especially when caused by central neurologic disorders; the associated pneumonia episodes represent the most frequent cause of death in these patients. Oro-pharyngo-esophageal scintigraphy (OPES) allows both functional imaging and semiquantitative evaluation of the subsequent phases of swallowing. CASE REPORT: We evaluated by means of OPES a woman who had previously undergone high-dose external beam radiation therapy for a nasopharyngeal carcinoma, which determined tissue fibrosis and progressive dysphagia. CONCLUSION: In this patient with dysphagia, OPES was a simple, inexpensive, noninvasive, and reliable technique that allowed to show the presence of bolus aspiration and quantified tracheobronchial aspirate.