Effect of Ursodeoxycholic Acid on the Biodistribution and Excretion of Technetium-99m Radiopharmaceuticals in Rat: A Potential Image Quality Enhancer

Purpose@#This study aimed to investigate the effect of ursodeoxycholic acid (UDCA) on the biodistribution and excretion of technetium-99m (Tc-99m)-labeled radiopharmaceuticals. @*Materials and Methods@#Tc-99m hydroxy-methylene-diphosphonate (HDP), Tc-99m pertechnetate, and Tc-99m dimercaptosuccinic acid (DMSA) were injected via the tail vein of rats. After 30 min, the control group was administered saline, and the UDCA group was given UDCA orally. Scintigraphy images were acquired after 30 min and 1, 2, 3, and 4 h. Radioactivity and rate of change were compared. Tc-99m mercaptoacetyltriglycine (MAG3) imaging was also performed. @*Results@#In image analysis of Tc-99m HDP, radioactivity of the buttock was lower in the UDCA group at 4 h. Rates of change in the buttock were significantly different at 3 h–30 min and 4 h–30 min, and buttock radioactivity in the UDCA group had decreased more. In analysis of Tc-99m pertechnetate, radioactivity of the buttock was higher in the control group. Rates of change in the thyroid gland and buttock were different at 1 h–30 min, 3 h–30 min, and 4 h–30 min, with radioactivity in the UDCA group decreasing more. In the analysis of Tc-99m DMSA, while the radioactivity of the kidneys in the control group showed little decrease at 1 h–30 min, that in the UDCA group increased. In the analysis of Tc-99m MAG3 images, radioactivity and radioactivity/total body radioactivity (TBA) values for the kidneys were higher in the UDCA group at 2 min. At 5 and 10 min, radioactivity/TBA values for soft tissue in the UDCA group were lower than those in the control group. @*Conclusion@#This study demonstrated that administration of UDCA increases renal excretion and soft tissue clearance of radiopharmaceuticals. This investigation could contribute to the broadening of applications of UDCA.

Usefulness of cyclic thermal therapy and red blood cell scintigraphy in patients with chemotherapy-induced peripheral neuropathy

Background@#Pharmacological and non-pharmacological therapies have been used to treat patients with chemotherapy-induced peripheral neuropathy (CIPN). However, the effect of therapies in cancer patients has yet to be investigated comprehensively. We hypothesized that cyclic thermal therapy would improve blood flow and microcirculation and improve the symptoms driven by CIPN. @*Methods@#The criteria of assessment were blood volume in region of interest (ROI) in the images, and European Organization for Research and Treatment of Cancer–Quality of Life Questionnaire–Chemotherapy-Induced Peripheral Neuropathy 20 questionnaire scores. The blood volume was quantified by using red blood cell (RBC) scintigraphy. All patients were treated 10 times during 10 days. The thermal stimulations, between 15° and 41°, were repeatedly delivered to the patient’s hands. @*Results@#The total score of the questionnaires, the score of questions related to the upper limbs, the score of questions closely related to the upper limbs, and the score excluding the upper limbs questions was decreased. The blood volume was decreased, and the variance of blood volume was decreased. During cooling stimulation, the blood volume was decreased, and its variance was decreased. During warming stimulation, the blood volume was decreased, and its variance was decreased. @*Conclusions@#We suggest that cyclic thermal therapy is useful to alleviate CIPN symptoms by blood circulation improvement. RBC scintigraphy can provide the quantitative information on blood volume under certain conditions such as stress, as well as rest, in peripheral tissue.

Effect of Ursodeoxycholic Acid on the Biodistribution and Excretion of Technetium-99m Radiopharmaceuticals in Rat: A Potential Image Quality Enhancer

Purpose@#This study aimed to investigate the effect of ursodeoxycholic acid (UDCA) on the biodistribution and excretion of technetium-99m (Tc-99m)-labeled radiopharmaceuticals. @*Materials and Methods@#Tc-99m hydroxy-methylene-diphosphonate (HDP), Tc-99m pertechnetate, and Tc-99m dimercaptosuccinic acid (DMSA) were injected via the tail vein of rats. After 30 min, the control group was administered saline, and the UDCA group was given UDCA orally. Scintigraphy images were acquired after 30 min and 1, 2, 3, and 4 h. Radioactivity and rate of change were compared. Tc-99m mercaptoacetyltriglycine (MAG3) imaging was also performed. @*Results@#In image analysis of Tc-99m HDP, radioactivity of the buttock was lower in the UDCA group at 4 h. Rates of change in the buttock were significantly different at 3 h–30 min and 4 h–30 min, and buttock radioactivity in the UDCA group had decreased more. In analysis of Tc-99m pertechnetate, radioactivity of the buttock was higher in the control group. Rates of change in the thyroid gland and buttock were different at 1 h–30 min, 3 h–30 min, and 4 h–30 min, with radioactivity in the UDCA group decreasing more. In the analysis of Tc-99m DMSA, while the radioactivity of the kidneys in the control group showed little decrease at 1 h–30 min, that in the UDCA group increased. In the analysis of Tc-99m MAG3 images, radioactivity and radioactivity/total body radioactivity (TBA) values for the kidneys were higher in the UDCA group at 2 min. At 5 and 10 min, radioactivity/TBA values for soft tissue in the UDCA group were lower than those in the control group. @*Conclusion@#This study demonstrated that administration of UDCA increases renal excretion and soft tissue clearance of radiopharmaceuticals. This investigation could contribute to the broadening of applications of UDCA.

Usefulness of cyclic thermal therapy and red blood cell scintigraphy in patients with chemotherapy-induced peripheral neuropathy

Background@#Pharmacological and non-pharmacological therapies have been used to treat patients with chemotherapy-induced peripheral neuropathy (CIPN). However, the effect of therapies in cancer patients has yet to be investigated comprehensively. We hypothesized that cyclic thermal therapy would improve blood flow and microcirculation and improve the symptoms driven by CIPN. @*Methods@#The criteria of assessment were blood volume in region of interest (ROI) in the images, and European Organization for Research and Treatment of Cancer–Quality of Life Questionnaire–Chemotherapy-Induced Peripheral Neuropathy 20 questionnaire scores. The blood volume was quantified by using red blood cell (RBC) scintigraphy. All patients were treated 10 times during 10 days. The thermal stimulations, between 15° and 41°, were repeatedly delivered to the patient’s hands. @*Results@#The total score of the questionnaires, the score of questions related to the upper limbs, the score of questions closely related to the upper limbs, and the score excluding the upper limbs questions was decreased. The blood volume was decreased, and the variance of blood volume was decreased. During cooling stimulation, the blood volume was decreased, and its variance was decreased. During warming stimulation, the blood volume was decreased, and its variance was decreased. @*Conclusions@#We suggest that cyclic thermal therapy is useful to alleviate CIPN symptoms by blood circulation improvement. RBC scintigraphy can provide the quantitative information on blood volume under certain conditions such as stress, as well as rest, in peripheral tissue.

Rodent Leukocyte Isolation and Radiolabeling for Inflammation Imaging Study / 대한핵의학회잡지

Purpose@#The objective of this study was to describe to develop methods of rodent leukocyte isolation and radiolabeling for in vivo inflammation imaging. @*Methods@#Thigh muscle inflammation was induced by injection of collagenase. Blood was collected from the jugular vein and separated by Histopaque. The collected cells were incubated in a 37 °C CO2 incubator for 1~2 h. After incubation, 99mTc-HMPAO and 18F-FDG were used to treat leukocytes followed by incubation for 30 min. 99mTc-HMPAO and 18F-FDG labeled autologous leukocytes were injected into the tail veins of rats. The images were then acquired at various time points. Image-based lesion to normal muscle ratio was compared. @*Results@#After Histopaque separation, the proportion of lymphocytes was higher than that of other cell types. After CO2 incubation, the collected leukocytes were viable, while room temperature exposed leukocytes without CO2 incubation were non-viable. Granulocytes, especially, were more quickly influenced by various conditions than the mononuclear cells. Labeling efficiencies of 99mTc-HMPAO and 18F-FDG were 4.00 ± 2.06 and 1.8%, respectively. 99mTc-HMPAO- and 18F-FDG-labeled leukocytes targeted well the inflamed lesion. 99mTc-HMPAO-labeled leukocytes, but not 18F-FDG-labeled leukocytes, were found in the abdomen activity. @*Conclusion@#Inflamed lesions of rats were well visualized using autologous radiolabeled leukocytes. This method might provide good information for understanding inflammatory diseases.

Radioactivity Reduction of 2-Deoxy-2-18F Fluoro-D-Glucose by Milkand Ursodeoxycholic Acid in Preclinical Study / 대한핵의학회잡지

Purpose@#2-Deoxy-2-[18F] fluoro-d-glucose positron emission tomography (18F-FDG-PET) is a less-invasive and widely useddiagnostic tool for detection of malignant tumors. However, prolonged retention of 18F-FDG in the body increases radiationexposure. This study evaluated the effect of oral administration of milk and ursodeoxycholic acid (UDCA) in terms of reducingradiation exposure by 18F-FDG. @*Methods@#18F-FDG radioactivity was measured using a digital γ counter in the whole body and in various organs of rats after oraladministration of milk andmilk plusUDCA (milk + UDCA).Western blotting was performed to measure the expression levels ofG6Pase, HK 2, CREB, FoxO1, and PGC-1α in the brain, liver, small intestine, and large intestine to assess the mechanismunderlying the reduction in radiation exposure from 18F-FDG by oral administration of milk and UDCA. @*Results@#We found a significant reduction in 18F-FDG radioactivity in the whole body and in the brain, liver, and small and largeintestines. Expression of G6Pase was significantly increased in the above-mentioned organs in the milk and milk + UDCAgroups. Expression of HK 2 was significantly decreased in the brain and small intestine in the milk and milk + UDCA groups.CREB, FoxO1, and PGC-1α expression levels in the brain, liver, and small intestine were increased in the milk and milk +UDCA groups. However, expression of PGC-1α in the large intestine in the milk and milk + UDCA groups was significantlydecreased compared with that in the control group. @*Conclusion@#The present study demonstrated that administration of milk and UDCA increased G6Pase expression levels and 18FFDGrelease from the tissue. These results suggest milk and UDCA could be used to reduce radiation exposure from 18F-FDGafter image acquisition. The mechanisms underpinning this phenomenon should be explored in a human study.

Size Control of 99mTc-tin Colloid Using PVP and Buffer Solution for Sentinel Lymph Node Detection

Colloidal particle size is an important characteristic that allows mapping sentinel nodes in lymphoscintigraphy. This investigation aimed to introduce different ways of making a 99mTc-tin colloid with a size of tens of nanometers. All agents, tin fluoride, sodium fluoride, poloxamer-188, and polyvinylpyrrolidone (PVP), were mixed and labeled with 99mTc. Either phosphate or sodium bicarbonate buffers were used to adjust the pH levels. When the buffers were added, the size of the colloids increased. However, as the PVP continued to increase, the size of the colloids was controlled to within tens of nanometers. In all samples, phosphate buffer added PVP (30 mg) stabilized tin colloid (99mTc-PPTC-30) and sodium bicarbonate solution added PVP (50 mg) stabilized tin colloid (99mTc-BPTC-50) were chosen for in vitro and in vivo studies. 99mTc-BPTC-50 (100 nm) mainly accumulated in the liver. When a rabbit was given a toe injection, the node uptake of 99mTc-PPTC-30 decreased over time, while 99mTc-BPTC-50 increased. Therefore, 99mTc-BPTC-50 could be a good candidate radiopharmaceutical for sentinel node detection. The significance of this study is that nano-sized tin colloid can be made very easily and quickly by PVP.

Pattern Analysis of 67Gallium Scintigraphy in Sarcoidosis / 결핵및호흡기질환

BACKGROUND: 67Ga scintigraphy has been used for years in sarcoidosis for diagnosis and to determine the extent of the disease. The present report is a study of various findings of 67Ga scintigraphy in patients with sarcoidosis. METHODS: Between 1998 and 2007, 16 patients (male:female, 6:10; age, 35.9+/-15.3 years) with histologically proven sarcoidosis underwent clinical evaluation and 67Ga scintigraphy. According to the site of involvement, they were divided into subtypes and analyzed. RESULTS: Sixteen patients with sarcoidosis had involvement of various organs, including lymph nodes (13/16, 81.3%), lung (3/16, 18.8%), muscle (1/16, 6.3%), subcutaneous tissue (1/16, 6.3%), glands (1/16, 6.3%), and bone (1/16, 6.3%). Sites of involved lymph nodes were thorax (12/13, 92.3%), supraclavicular area (5/13, 38.5%), inguinal area (2/13, 15.4%), abdomen (2/13, 15.4%), and pelvis (1/13, 7.7%). CONCLUSION: Because sarcoidosis frequently involves multiple organs, 67Ga scintigraphy is a useful method in for evaluating the whole body. Nuclear medicine physicians should be familiar with the various findings of gallium uptake in sarcoidosis.

The Clinical Value of Dual Time Point F-18 FDG PET/CT Imaging for the Differentiation of Colonic Focal Uptake Lesions / 핵의학분자영상

PURPOSE: F-18 FDG can be accumulated in the liver, bowel, kidney, urinary tract, and muscles physiologically. The aim of this study was to evaluate the clinical value of dual time point 18F-FDG PET/CT imaging for the differentiation of the colonic focal uptake lesions. MATERIALS AND METHODS: One hundred thirty two patients (M:F=77:55, Age 62.8 +/-11.6 years) underwent 18F-FDG PET/CT at two time points, prospectively: early image at 50-60 min and delayed image at 4-4.5 hours after the intravenous injection of 18F-FDG. Focally increased uptake lesions on early images but disappeared or shifted on delayed images defined a physiological uptake. For the differential evaluation of persistent focal uptake lesions on delayed images, colonoscopy and histopathologic examination were performed. SUVmax changes between early and delayed images were also compared. RESULTS: Among the 132 patients, 153 lesions of focal colonic uptake were detected on early images of 18F-FDG PET/CT. Of these, 72 (47.1%) lesions were able to judge with physiological uptake because the focal increased uptake disappeared from delayed image. Among 81 lesions which was showed persistent increased uptake in delayed image, 61 (75.3%) lesions were confirmed as the malignant tumor and 14 (17.3%) lesions were confirmed as the benign lesions including adenoma and inflammatory disease. Remaining 6 (7.4%) lesions were confirmed as the physiological uptake because there was no particular lesion in the colonoscopy. In the malignant lesions, the calculated dual time point change for SUVmax (delta%SUVmax) was 20.8%+/-18.7%, indicating a significant increase in SUVmax between the two point (p<0.01). In contrast, the change in SUVmax for the non-malignant lesions including benign lesions and physiological uptake was -13.7%+/-24.2%. For the differentiation of the malignant and non-malignant focal colonic uptake lesions, delta%SUVmax was the most effective parameter, and the cut-off value using -5% provided the best sensitivity, specificity, and accuracy. CONCLUSION: The dual time point 18F-FDG PET/CT imaging with SUVmax change evaluation could be an important noninvasive method for the differentiation of malignant and benign focal colonic uptake lesions including physiologic uptake.

Different 18F-FDG Uptake According to Tumor Location and Morphology of Cholangiocarcinoma and Its Clinical Implication / 핵의학분자영상

PURPOSE: 18F-flurodeoxyglucose (FDG) uptake on positron emission tomography (PET) scan has been found to reflect tumor aggressiveness and prognosis in various types of cancer. However, pattern of FDG uptake in biliary malignancies and its clinical significance have not been studied well. The purpose of this study was to assess the additional value of 18F-FDG PET in differential diagnosis and prognosis of cholangiocarcinoma (CC) according to the tumor location and tumor morphology. MATERIALS AND METHODS: From April 2005 to May 2008, eighty two patients (M:F=55:27, age 66.2+/-9.6 yrs) with CC underwent 18F-FDG PET. For semiquantitative analysis, the maximum standardized uptake value (SUVmax) was obtained from the primary tumor. The difference of SUVmax according to the tumor location and tumor growth pattern, such as scirrhous type, nodular type, polypoid type were compared. RESULTS: Overall sensitivity of PET scan was 81.7% in CC. SUVmax on PET scan in intrahepatic CC was significantly higher compared to extrahepatic CC. In extrahepatic CC, polypoid type showed significantly higher SUVmax compared to scirrhous type. CONCLUSION: 18F-FDG PET may have a significant impact on clinical decision-making and on the management of Intrahepatic cholangiocarcinoma. And it is related to the shape of the tumor and the sensitivity of detection is higher in the mass-forming type than in the scirrhous type.

Efficacy of I-123/I-131 Metaiodobenzylguanidine Scan as A Single Initial Diagnostic Modality in Pheochromocytoma: Comparison with Biochemical Test and Anatomic Imaging / 핵의학분자영상

PURPOSE: We underwent this study to evaluate the diagnostic potential of I-123/I-131 metaiodobenzylguanidine (MIBG) scintigraphy alone in the initial diagnosis of pheochromocytoma, compared with biochemical test and anatomic imaging. MATERIALS & METHODS: Twenty two patients (M:F=13:9, Age: 44.3+/- 19.3 years) having the clinical evaluation due to suspicious pheochromocytoma received the biochemical test, anatomic imaging modality (CT and/or MRI) and I-123/I-131 MIBG scan for diagnosis of pheochromocytoma, prior to histopathological confirmation. MIBG scans were independently reviewed by 2 nuclear medicine physicians. RESULTS: All patients were confirmed histopathologically by operation or biopsy (incisional or excisonal). In comparison of final diagnosis and findings of each diagnostic modality, the sensitivities of the biochemical test, anatomic imaging, and MIBG scan were 88.9%, 55.6%, and 88.9%, respectively. And the specificities of the biochemical test, anatomic imaging, and MIBG scan also were 69.2%, 69.2%, and 92.3%, respectively. MIBG scan showed one false positive (neuroblastoma) and one false negative finding. There was one patient with positive MIBG scan and negative findings of the biochemical test, anatomic imaging. CONCLUSION: Our data suggest that I-123/I-131 MIBG scan has higher sensitivity, specificity, positive predictive value, negative predictive value and accuracy than those of biochemical test and anatomic imaging. Thus, we expect that MIBG scan is e tectively used for initial diagnosis of pheochromocytoma alone as well as biochemical test and anatomic imaging.

Assessment of Prognosis and Risk Stratification in Coronary Artery Disease / 핵의학분자영상

Risk stratification and assessment of prognosis in patients with known or suspected CAD is of crucial important for the practice of contemporary medicine. Noninvasive testing such as myocardial perfusion scintigraphy, coronary artery calcium scoring or CT coronary angiography is increasingly being used to determine the need for aggressive medical therapy and to select patients for catheterization. The integrated anatomic and functional information may provide more additional information for the cardiologist or other clinician by the improved risk stratification and diagnostic accuracy of integrated techniques. The development of SPECT/CT or PET/CT hybrid systems is therefore of important value for the nuclear cardiology.

Added Value of 3D Cardiac SPECT/CTA Fusion Imaging in Patients with Reversible Perfusion Defect on Myocardial Perfusion SPECT / 핵의학분자영상

PURPOSE: Integration of the functional information of myocardial perfusion SPECT (MPS) and the morphoanatomical information of coronary CT angiography (CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. We studied to know the added value of three dimensional cardiac SPECT/CTA fusion imaging (fusion image) by comparing between fusion image and MPS. MATERIALS AND METHODS: Forty-eight patients (M:F=26:22, Age: 63.3+/-10.4 years) with a reversible perfusion defect on MPS (adenosine stress/rest SPECT with Tc-99m sestamibi or tetrofosmin) and CTA were included. Fusion images were molded and compared with the findings from the MPS. Invasive coronary angiography served as a reference standard for fusion image and MPS. RESULTS: Total 144 coronary arteries in 48 patients were analyzed; Fusion image yielded the sensitivity, specificity, negative and positive predictive value for the detection of hemodynamically significant stenosis per coronary artery 82.5%, 79.3%, 76.7% and 84.6%, respectively. Respective values for the MPS were 68.8%, 70.7%, 62.1% and 76.4%. And fusion image also could detect more multi-vessel disease. CONCLUSION: Fused three dimensional volume-rendered SPECT/CTA imaging provides intuitive convincing information about hemodynamic relevant lesion and could improved diagnostic accuracy.

The Clinical Utility of Rectal Gas Distension F-18 FDG PET/CT / 핵의학분자영상

PURPOSE: The aim of this study was to evaluate the clinical value of rectal gas distension F-18 FDG PET/CT imaging for the differentiation of the rectal focal uptake lesions. MATERIALS AND METHODS: Twenty four patients (M:F=11:13, Age 62.8+/-12.4 years) underwent rectal gas distension F-18 FDG PET/CT, prospectively: initial image at 50-60 min after the intravenous injection of F-18 FDG and rectal distension image after the infusion of air through the anus. Focally increased uptake lesions on initial images but disappeared on rectal distension images defined a physiological uptake. For the differential evaluation of persistent focal uptake lesions on rectal distension images, colonoscopy and histopathologic examination were performed. RESULTS: Among the 24 patients, 27 lesions of focal rectal uptake were detected on initial images of F-18 FDG PET/CT. Of these, 7 lesions were able to judge with physiological uptake because the focal increased uptake disappeared from rectal distension image. Remaining 3 lesions were non-rectal lesions (2 lesions: rectovesical space, 1 lesion: uterine myoma). Among 17 lesions which was showed persistent increased uptake in rectal distension image, 15 lesions were confirmed as the malignant tumor (SUVmax=15.9+/-6.8) and 2 lesions were confirmed as the benign lesions including adenoma and inflammatory disease. CONCLUSION: The rectal distension F-18 FDG PET/CT imaging could be an important noninvasive method for the differentiation of malignant and benign focal rectal uptake lesions including physiologic uptake.

Clinical Usefulness between High Dose Radioiodine Therapy and Helicobacter Pylori Infection after Total Thyroidectomy due to Well Differentiated Thyroid Cancer / 핵의학분자영상

PURPOSE: Helicobacter (H) pylori infection has been considered the most important cause of gastritis, dyspepsia, and gastroduodenal ulcer. Radioiodine can be accumulated in the remaining thyroid tissue, salivary gland, and stomach. We investigated if the high radiation induced by radioiodine in the stomach after high dose radioiodine therapy (HD-RIT) is effective in the eradication of H. pylori infection. MATERIALS AND METHODS: One hundred ninety nine patients (M:F=33:166, age 46.7+/-12.3 years) who had HD-RIT (dose 159.1+/-25.9 mCi, range 120-250 mCi) after thyroidectomy due to well differentiated thyroid cancer were enrolled. To detect H. pylori infection, the urea breath tests (UBT) were performed at 1 hour before HD-RIT and at 4 weeks after HD-RIT. The results of UBT were classified as positive (> or =50 dpm) or negative (<50 dpm), and analyzed its values. RESULTS: Of 199 patients, 103 (51.8%) patients had positive UBT before HD-RIT. Of these, 80 patients had follow-up UBT after HD-RIT. Among them, 76 (95.0%) patients had persistent positive UBT and only 4 (5.0%) patients were changed negative UBT. Among 76 patients with persistent positive UBT, 26 (34.2%) patients had increased the values of follow-up UBT, 49 (64.5%) had decreased them, and 1 (1.3%) had shown the same value. The different values of UBT between before and after HD-RIT were 62+/-66.1 dpm in increased one of follow-up UBT, and 153.3+/-157.1 dpm in decreased one of follow-up UBT. CONCLUSION: We conclude that the radiation induced by HD-RIT is ineffective in the eradication of H. pylori infection. However, it could be influential the degree or distribution of H. pylori infection.

The Clinical Significance of Diffuse Thyroid Uptake That is Incidentally Identified by F-18 FDG PET/CT Imaging in Patients with Breast Cancer / 한국유방암학회지

PURPOSE: This study was to investigate the clinical significance of diffusely increased F-18 FDG uptake in the thyroid gland as an incidental finding on F-18 FDG PET/CT imaging in patients with breast carcinoma. METHODS: One hundred four patients with breast carcinoma who had no prior history of thyroid disease were enrolled. All patients underwent F-18 FDG PET/CT, ultrasound and thyroid function test (TFT-TSH, FT4, and T3), anti-TPO antibody test within 2 weeks. Also we checked estrogen (ER) and progesterone receptors (PR). We classified all patients into subgroups according to the existence and degree of F-18 FDG uptake in the thyroid gland, and evaluated the difference between subgroups. RESULTS: Of the 104 patients, 42 (40.4%) subjects showed diffusely increased thyroid uptakes. There was no significant difference in rate of abnormality in TFT and thyroid US, and existence of anti-TPO antibody and ER/PR between two groups. Of 42 patient who showed diffuse uptake, 12 (28.5%), 13 (31.0%), and 17 (40.5%) subjects demonstrated hypointense, isointense, and hyperintense thyroid uptake compared with activity of mediastinal blood pool. Thirteen (76.4%) of 17 subjects in the hyperintense thyroid uptake group revealed abnormality in various tests (US, TFT, and anti-TPO antibody). The rate of abnormality in this group was significantly different with the other two groups (p=0.002). CONCLUSION: Our data suggested that the rate of diffuse thyroid uptakes on F-18 FDG PET/CT imaging of patients with breast carcinoma was higher than healthy subjects. In case of someone who had no prior thyroid disease showed diffuse thyroid uptakes more than activity of mediastinal blood pool on F-18 FDG PET/CT imaging, it should be considered further evaluation about the thyroid gland.

Nucleophilic Fluorination Reactions in Novel Reaction Media for 18F-Fluorine Labeling Method / 핵의학분자영상

Noninvasive imaging of molecular and biological processes in living subjects with positron emission tomography (PET) provides exciting opportunities to monitor metabolism and detect diseases in humans. Measuring these processes with PET requires the preparation of specific molecular imaging probes labeled with 18F-fluorine. In this review we describe recent methods and novel trends for the introduction of 18F-fluorine into molecules which in turn are intended to serve as imaging agents for PET study. Nucleophilic 18F-fluorination of some halo- and mesyloxyalkanes to the corresponding 18F-fluoroalkanes with 18F-fluoride obtained from an 18O(p,n)18F reaction, using novel reaction media system such as an ionic liquidor tert-alcohol, has been studied as a new method for 18F-fluorine labeling. Ionic liquid method is rapid and particularly convenient because 18F-fluoride in H2O can be added directly to the reaction media, obviating the careful drying that is typically required for currently used radiofluorination methods. The nonpolar protic tert-alcohol enhances the nucleophilicity of the fluoride ion dramatically in the absence of any kind of catalyst, greatly increasing the rate of the nucleophilic fluorination and reducing formation of byproducts compared with conventional methods using dipolar aprotic solvents. The great efficacy of this method is a particular advantage in labeling radiopharmaceuticals with 18F-fluorine for PETimaging, and it is illustrated by the synthesis of 18F-fluoride radiolabeled molecular imaging probes, such as 18F-FDG, 18F-FLT, 18F-FP-CIT, and 18F-FMISO, in high yield and purity and in shorter times compared to conventional syntheses

Incidental Visualization of Thyroid Gland on Bone Scan Caused by Graves' Hyperthyroidism / 핵의학분자영상

A 45-year-old man presented with fatigue and weight loss underwent a Tc-99m MDP bone scan because of increased serum alkaline phosphatase. Delayed images at 4 hours demonstrated diffuse increased activity throughout both lobes of the thyroid in the absence of activity of the stomach and salivary glands. Thyroid laboratory indices and a Tc-99m pertechnetate thyroid scan suggested Graves' hyperthyroidism.

Primary Malignant Peritoneal Mesothelioma Mimicking Peritoneal Carcinomatosis on F-18 FDG PET/CT / 핵의학분자영상

Malignant mesothelioma of the peritoneum is a rare neoplasm with a rapidly fatal course. The tumour arises from the mesothelial cells lining the pleura and peritoneum or, rarely, in the pericardium or tunica vaginalis. This neoplasm is characterized by being difficult to diagnose, having a rapid evolution and a poor response to therapy. Mesothelioma is very glucose avid, and malignant pleural mesothelioma has been reported concerning the utility of F-18 FDG PET or PET/CT. But little has been known about the imaging finding of malignant peritoneal mesothelioma on F-18 FDG PET/CT. We report a case of malignant peritoneal mesothelioma mimicking peritoneal carcinomatosis of F-18 FDG PET/CT.

Ga-67 Citrate and Tc-99m MDP Uptake in the Lung and Stomach Associated with Hypercalcemia / 핵의학분자영상

Ga-67 scintigraphy demonstrated increased uptake in the lungs and stomach in a 26-year-old man with hypercalcemia. A primitive neuroectodermal tumor was confirmed by bone marrow examination. Tc-99m MDP uptake in the same locations as Ga-67 revealed by bone scintigraphy was consistent with metastatic calcification. Although the mechanism of Ga-67 uptake in metastatic calcification is not understood, the presence of an inflammatory process is suggested.