BACKGROUND: Postoperative routine radioiodine (RAI) treatment is currently debated for patients with low-risk differentiated thyroid carcinoma (DTC) patients. If performed, a low 131I activity (i.e., 1 to 2 GBq) is recommended with the aim to ablate thyroid remnant and facilitate subsequent follow-up by thyroglobulin measurement. The purpose of this study was to evaluate the relationship between postsurgical technetium-99m (99mTc)-pertechnetate scintigraphy and the rate of successful remnant ablation after low activity radioiodine ablation in patients with DTC. METHODS: Enrolled were 193 patients with low risk DTC who underwent total thyroidectomy and RAI ablation with a fixed 1.1 GBq activity of 131I. 99mTc-pertechnetate scans were done and thyrotropin stimulated thyroglobulin (sTg) levels measured just before ablation. Ablation effectiveness was assessed 6 to 12 months later by sTg measurement, neck ultrasound and diagnostic whole body scan. RESULTS: A negative 99mTc-perthecnetate scans was the best predictor of successful ablation (P<0.001) followed by preablative sTg levels <0.8 ng/mL (P=0.008) and 99mTc-pertechnetate uptake rate values <0.9% (P=0.065). Neither sex nor age of the patient at the time of ablation or tumor histology and size showed a significant association with the rate of successful ablation. CONCLUSION: The 99mTc-pertechnetate scintigraphy is a simple and feasible tool to predict effectiveness of low activity 131I thyroid to ablate thyroid remnants in patients with DTC.
Follow-Up Studies ; Humans ; Neck ; Radionuclide Imaging ; Sodium Pertechnetate Tc 99m ; Thyroglobulin ; Thyroid Gland ; Thyroid Neoplasms ; Thyroidectomy ; Thyrotropin ; Ultrasonography ; Whole Body Imaging

Single-photon emission computed tomography/computed tomography (SPECT/CT) is an already established nuclear imaging modality. Co-registration of functional information (SPECT) with anatomical images (CT) paved the way to the wider application of SPECT. Recent advancements in quantitative SPECT/CT have made it possible to incorporate quantitative parameters, such as standardized uptake value (SUV) or %injected dose (%ID), in gamma camera imaging. This is indeed a paradigm shift in gamma camera imaging from qualitative to quantitative evaluation. In fact, such quantitative approaches of nuclear imaging have only been accomplished for positron emission tomography (PET) technology. Attenuation correction, scatter correction, and resolution recovery are the three main features that enabled quantitative SPECT/CT. Further technical improvements are being achieved for partial-volume correction, motion correction, and dead-time correction. The reported clinical applications for quantitative SPECT/CT are mainly related to Tc-99m-labeled radiopharmaceuticals: Tc-99m diphosphonate for bone/joint diseases, Tc-99m pertechnetate for thyroid function, and Tc-99m diethylenetriaminepentaacetic acid for measurement of glomerular filtration rate. Dosimetry before trans-arterial radio-embolization is also a promising application for Tc-99m macro-aggregated albumin. In this review, clinical applications of Tc-99m quantitative SPECT/CT will be discussed.
Evaluation Studies as Topic ; Gamma Cameras ; Glomerular Filtration Rate ; Positron-Emission Tomography ; Radionuclide Imaging ; Radiopharmaceuticals ; Sodium Pertechnetate Tc 99m ; Thyroid Gland ; Tomography, Emission-Computed, Single-Photon

OBJECTIVE: Quantitative parameters from Tc-99m pertechnetate single-photon emission computed tomography/computed tomography (SPECT/CT) are emerging as novel diagnostic markers for functional thyroid diseases. We intended to assess the utility of SPECT/CT parameters in patients with destructive thyroiditis. MATERIALS AND METHODS: Thirty-five destructive thyroiditis patients (7 males and 28 females; mean age, 47.3 ± 13.0 years) and 20 euthyroid patients (6 males and 14 females; mean age, 45.0 ± 14.8 years) who underwent Tc-99m pertechnetate quantitative SPECT/CT were retrospectively enrolled. Quantitative parameters from the SPECT/CT (%uptake, standardized uptake value [SUV], thyroid volume, and functional thyroid mass [SUVmean × thyroid volume]) and thyroid hormone levels were investigated to assess correlations and predict the prognosis for destructive thyroiditis. The occurrence of hypothyroidism was the outcome for prognosis. RESULTS: All the SPECT/CT quantitative parameters were significantly lower in the 35 destructive thyroiditis patients compared to the 20 euthyroid patients using the same SPECT/CT scanner and protocol (p < 0.001 for all parameters). T3 and free T4 did not correlate with any SPECT/CT parameters, but thyroid-stimulating hormone (TSH) significantly correlated with %uptake (p = 0.004), SUVmean (p < 0.001), SUVmax (p = 0.002), and functional thyroid mass (p < 0.001). Of the 35 destructive thyroiditis patients, 16 progressed to hypothyroidism. On univariate and multivariate analyses, only T3 levels were associated with the later occurrence of hypothyroidism (p = 0.002, exp(β) = 1.022, 95% confidence interval: 1.008 – 1.035). CONCLUSION: Novel quantitative SPECT/CT parameters could discriminate patients with destructive thyroiditis from euthyroid patients, suggesting the robustness of the quantitative SPECT/CT approach. However, disease progression of destructive thyroiditis could not be predicted using the parameters, as these only correlated with TSH, but not with T3, the sole predictor of the later occurrence of hypothyroidism.
Disease Progression ; Female ; Humans ; Hypothyroidism ; Male ; Multivariate Analysis ; Prognosis ; Retrospective Studies ; Sodium Pertechnetate Tc 99m ; Thyroid Diseases ; Thyroid Gland* ; Thyroiditis* ; Thyrotropin

PURPOSE: The purpose of the study was to investigate the usefulness of quantitative salivary single-photon emission computed tomography/computed tomography (SPECT/CT) using Tc-99m pertechnetate in Sjögren's syndrome (SS).METHODS: We retrospectively reviewed quantitative salivary SPECT/CT data from 95 xerostomic patients who were classified as either SS (n = 47, male:female = 0:47, age = 54.60 ± 13.16 y [mean ± SD]) or non-SS (n = 48, male:female = 5:43, age = 54.94 ± 14.04 y) by combination of anti-SSA/Ro antibody, labial salivary gland biopsy, unstimulated whole saliva flow rate, and Schirmer's test. Thyroid cancer patients (n = 43, male:female = 19:24, age = 46.37 ± 12.13 y) before radioactive iodine therapy served as negative controls. Quantitative SPECT/CT was performed pre-stimulatory 20 min and post-stimulatory 40 min after injection of Tc-99m pertechnetate (15 mCi). The %injected dose at 20 min and the %excretion between 20 and 40 min were calculated for parotid and submandibular glands, generating four quantitative parameters: %parotid uptake (%PU), %submandibular uptake (%SU), %parotid excretion (%PE), and %submandibular excretion (%SE). The most useful parameter for SS diagnosis was investigated.RESULTS: The uptake parameters (%PU and %SU) were significantly different among the SS, non-SS, and negative controls (p = 0.005 for %PU and p < 0.001 for %SU, respectively), but the excretion parameters (%PE and %SE) were not (p > 0.05 for both). The%PU and%SU were significantly lower in SS than in the negative controls and non-SS (p < 0.05 for all pair-wise comparisons). Additionally, the %SU was significantly lower in non-SS than in the negative controls (p < 0.05). Receiver-operating characteristic analysis revealed that the %SU had the greatest area-under-the curve of 0.720 (95% confidence interval = 0.618–0.807). Using the optimal cut-off value of %SU ≤ 0.07%, SS was identified with a sensitivity of 70.21% and a specificity of 70.83%.CONCLUSION: Reduced submandibular uptake of Tc-99m pertechnetate at 20 min (%SU) was proved useful for the diagnosis of SS. Quantitative salivary gland SPECT/CT holds promise as an objective imaging modality for assessment of salivary dysfunction and may facilitate accurate classification of SS.
Biopsy ; Classification ; Diagnosis ; Humans ; Iodine ; Retrospective Studies ; Saliva ; Salivary Glands ; Sensitivity and Specificity ; Sodium Pertechnetate Tc 99m ; Submandibular Gland ; Thyroid Neoplasms

Planar scintigraphy using Tc-99mpertechnetate is useful for snapshot evaluation of hot thyroid nodules, which are pathologically follicular adenoma and seldom, if ever, malignant. The autonomy of the hot nodules has been demonstrated by the presence of thyroid-stimulating hormone-dependent extra-nodular thyroid tissue besides the hot nodules. Here, we present two cases of hot thyroid nodules in patients who underwent quantitative single-photon emission computed tomography/computed tomography (SPECT/CT). In addition to the nodules, contralateral normal thyroid parenchyma was evaluated based on standardized uptake values. One patient had a traditional follicular adenoma suppressing other thyroid tissue, whereas the other patient seemed to have a nodule erupting from underlying hyperfunctioning, not suppressed, thyroid tissue. This novel approach using quantitative SPECT/CT unveils a new pathology of hot thyroid nodule that does not suppress, but coincides with hyperfunctioning thyroid tissue.
Adenoma ; Humans ; Pathology ; Radionuclide Imaging ; Sodium Pertechnetate Tc 99m ; Thyroid Gland ; Thyroid Nodule

A 77-year-old male underwent open repair for a right indirect inguinal hernia and complained of right scrotal pain on the third postoperative day. Color Doppler imaging revealed decreased blood flow with heterogeneous hypoechogenicity in the right testis. A Tc-99m pertechnetate testicular scan showed diffuse hyperemia and increased uptake in the right scrotum. Additional SPECT/CT revealed a photon defect in the right testicle with increased uptake in the peri-testicular area. A subsequent operation revealed a large hematoma in the right spermatic cord and consequent right testicular infarction, and right orchiectomy was performed.
Aged ; Diagnosis ; Hematoma ; Hernia, Inguinal ; Herniorrhaphy ; Humans ; Hyperemia ; Infarction ; Male ; Orchiectomy ; Scrotum ; Sodium Pertechnetate Tc 99m ; Spermatic Cord ; Testis

OBJECTIVES: Radioiodine (RI) therapy is known to subject cellular components of salivary glands (SG) to oxidative stress leading to SG dysfunction. However, the protective effects of antioxidants on RI-induced SG damage have not been well investigated. The authors investigated the morphometric and functional effects of epigallocatechin-3-gallate (EGCG) administered prior to RI therapy and compared this with the effects of amifostine (a well-known antioxidant) in a murine model of RI sialadenitis. METHODS: Four-week-old female C57BL/6 mice (n=48) were divided into four groups; a normal control group, a RI-treated group (0.01 mCi/g mouse, orally), an EGCG and RI-treated group, and an amifostine and RI-treated group. Animals in these groups were divided into 3 subgroups and euthanized at 15, 30, and 90 days post-RI treatment. Salivary flow rates and lag times were measured, and morphologic and histologic examinations and TUNEL (terminal deoxynucleotidyl transferase biotin-dUDP nick end labeling) assays were performed. Changes in salivary (99m)Tc pertechnetate uptake and excretion were followed by single-photon emission computed tomography. RESULTS: Salivary flow rates and lag times to salivation in the EGCG or amifostine groups were better than in the RI-treated group. Histologic examinations of SGs in the EGCG or amifostine group showed more mucin-rich parenchyma and less periductal fibrosis than in the RI-treated group. Fewer apoptotic cells were observed in acini, ducts, and among endothelial cells in the EGCG or amifostine group than in the RI group. In addition, patterns of (99m)Tc pertechnetate excretion were quite different in the EGCG or amifostine group than in the RI group. CONCLUSION: EGCG supplementation before RI therapy could protect from RI-induced SG damage in a manner comparable to amifostine, and thus, offers a possible means of preventing SG damage by RI.
Amifostine ; Animals ; Antioxidants ; DNA Nucleotidylexotransferase ; Endothelial Cells ; Female ; Fibrosis ; Humans ; In Situ Nick-End Labeling ; Mice ; Models, Animal ; Oxidative Stress ; Salivary Glands* ; Salivation ; Sialadenitis ; Sodium Pertechnetate Tc 99m ; Thyroid Neoplasms ; Tomography, Emission-Computed ; Tomography, Emission-Computed, Single-Photon

No abstract available.
Adult ; Biological Markers/blood ; Female ; Humans ; Mouth Floor ; *Neck/radiography/radionuclide imaging/ultrasonography ; Predictive Value of Tests ; Radiopharmaceuticals/diagnostic use ; Sodium Pertechnetate Tc 99m/diagnostic use ; Thyroid Dysgenesis/blood/*diagnosis/drug therapy ; Thyroid Function Tests ; *Thyroid Gland/drug effects/metabolism/radiography/radionuclide imaging/ultrasonography ; Thyrotropin/blood ; Thyroxine/blood/therapeutic use ; Tomography, X-Ray Computed

A 28-year-old Chinese man presented with acute bleeding per rectum. Computed tomography showed a posterior outpouching arising from the distal ileum. The outpouching had hyperaemic walls, but no active contrast extravasation was detected. Technetium-99m pertechnetate scintigraphy showed focal areas of abnormal uptake in the right side of the pelvis, superior and posterior to the urinary bladder. These areas of uptake appeared simultaneously with the gastric uptake and demonstrated gradual increase in intensity on subsequent images. The diagnosis of Meckel's diverticulum was confirmed on surgery and the lesion was resected. The clinical and imaging features of Meckel's diverticulum are discussed.
Abdominal Pain ; Adult ; Female ; Gastrointestinal Hemorrhage ; diagnosis ; diagnostic imaging ; Humans ; Ileum ; diagnostic imaging ; Male ; Meckel Diverticulum ; diagnosis ; diagnostic imaging ; Radionuclide Imaging ; Radiopharmaceuticals ; Sodium Pertechnetate Tc 99m ; Tomography, X-Ray Computed

No abstract available.
Adolescent ; Capsule Endoscopy ; Endoscopy, Gastrointestinal ; Humans ; Male ; Meckel Diverticulum/*diagnosis/radionuclide imaging/surgery ; Radiography, Abdominal ; Radiopharmaceuticals/diagnostic use ; Sodium Pertechnetate Tc 99m/diagnostic use ; Surgical Instruments ; Tomography, X-Ray Computed