OBJECTIVE: To provide useful information for the further production and application of this novel radio-nuclide for potential clinical application. METHODS: ¹²⁴Te (p,n) ¹²⁴I nuclide reaction was used for the ¹²⁴I production. Firstly, the target material, ¹²⁴TeO₂ (200 mg) and Al2O3 (30 mg) mixture, were compressed into the round platinum based solid target by tablet device. HM-20 medical cyclotron was applied to irradiate the solid target slice for 6-10 h with helium and water cooling. Then, the radiated solid target was placed for 12 h (overnight) to decay the radioactive impurity; finally, ¹²⁴I was be purified by dry distillation using 1 mL/min nitrogen for about 6 hours and radiochemical separation methods. Micro-PET imaging studies were performed to investigate the metabolism properties and thyroid imaging ability of ¹²⁴I.After 740 kBq ¹²⁴I was injected intravenously into the tail vein of the normal mice, the animals were imaged with micro-PET and infused with CT. The micro-PET/CT infusion imaging revealed actual state ¹²⁴I's metabolism in the mice. RESULTS: It was been successfully applied for 200 mg ¹²⁴TeO₂ plating by the tablet device on the surface of platinum. It showed smooth, dense surface and without obviously pits and cracks. The enriched ¹²⁴Te target was irradiated for 6 to 10 hours at about 12.0 MeV with 20 μA current on HM-20 cyclotron. Then 370-1 110 MBq ¹²⁴I could be produced on the solid target after irradiation and 370-740 MBq high specific activity could be collected afterdry distillation separation and radio-chemical purification.¹²⁴I product was finally dissolved in 0.01 mol/L NaOH for the future distribution. The gamma spectrum of the produced ¹²⁴I-solution showed that radionuclide purity was over 80.0%. The micro-PET imaging of ¹²⁴I in the normal mice exhibited the thyroid and stomach accumulations and kidney metabolism, the bladder could also be clearly visible, which was in accordance with what was previously reported. To the best of our knowledge, it was the first production of ¹²⁴I report in China. CONCLUSION In this study, the preparation of ¹²⁴TeO₂ solid target was successfully carried out by using the tablet device. After irradiation of the ¹²⁴TeO₂ solid target and radio-chemical purification, we successfully produced 370-740 MBq high specific activity ¹²⁴I by a cyclotron for biomedical application, and micro-PET imaging of ¹²⁴I in normal mice exhibited the thyroid accumulations. Also, slight uptake in stomach were also monitored with almost nonuptake in other organs in the micro-PET imaging. The production of ¹²⁴I is expected to provide a new solid target radionuclide for the scientific research and potential clinical application of our country.
Animals ; China ; Cyclotrons ; Iodine Radioisotopes/standards* ; Mice ; Positron Emission Tomography Computed Tomography ; Quality Control ; Radiochemistry ; Radiopharmaceuticals/standards* ; Thyroid Gland/diagnostic imaging* ; Tomography, Emission-Computed

BACKGROUND/AIMS: Few studies have assessed the prognostic value of the primary tumor maximum standardized uptake value (SUVmax) measured by 2-[18F]-fluoro-2-deoxy-D-glucose PET-CT for patients with bile duct and gallbladder cancer. METHODS: A retrospective analysis of 61 patients with confirmed bile duct and gallbladder cancer who underwent FDG PET-CT in Kangbuk Samsung Medical Center (Seoul, Korea) from April 2008 to April 2011. Prognostic significance of SUVmax and other clinicopathological variables was assessed. RESULTS: Twenty-three patients were diagnosed as common bile duct cancer, 17 as hilar bile duct cancer, 12 as intrahepatic bile duct cancer, and nine as gallbladder cancer. In univariate analysis, diagnosis of intrahepatic cholangiocarcinoma and gallbladder cancer, mass forming type, poorly differentiated cell type, nonsurgical treatment, advanced American Joint Committee on Cancer (AJCC) staging and primary tumor SUVmax were significant predictors of poor overall survival. In multivariate analysis adjusted for age and sex, primary tumor SUVmax (hazard ratio [HR], 4.526; 95% CI, 1.813-11.299), advanced AJCC staging (HR, 4.843; 95% CI, 1.760-13.328), and nonsurgical treatment (HR, 6.029; 95% CI, 1.989-18.271) were independently associated with poor overall survival. CONCLUSIONS: Primary tumor SUVmax measured by FDG PET-CT is an independent and significant prognostic factor for overall survival in bile duct and gallbladder cancer.
Aged ; Bile Duct Neoplasms/*diagnosis/mortality/radionuclide imaging ; Cholangiocarcinoma/diagnosis/mortality/radionuclide imaging ; Female ; Fluorodeoxyglucose F18/diagnostic use/metabolism/standards ; Gallbladder Neoplasms/*diagnosis/mortality/radionuclide imaging ; Humans ; Kaplan-Meier Estimate ; Liver Neoplasms/diagnosis/mortality/radionuclide imaging ; Male ; Middle Aged ; Neoplasm Staging ; Positron-Emission Tomography/standards ; Prognosis ; Proportional Hazards Models ; Radiopharmaceuticals/diagnostic use/metabolism/standards ; Retrospective Studies ; Tomography, X-Ray Computed/standards

Nuclear medicine is a rapidly growing discipline that employs advanced novel hybrid techniques that provide unique anatomical and functional information, as well as targets for molecular therapy. Concomitantly, there has been an increase in the attention paid to medical radiation exposure. A radiological justification for the practice of nuclear medicine has been implemented mainly through referral guidelines based on research results such as prospective randomized clinical trials. The International Commission on Radiological Protection recommends diagnostic reference levels as a practical mechanism to optimize medical radiation exposure in order to be commensurate with the medical purpose. The Korean Society of Nuclear Medicine has been implementing radiological optimization through a survey of the protocols on how each hospital determines the dose of administration of each radiopharmaceutical. In the case of nuclear medicine, radiation exposure of caregivers and comforters of patients discharged after administration of therapeutic radiopharmaceuticals can occur; therefore, optimization has been implemented through written instructions for patients, based on international recommendations. The development of patient-radiation-dose monitoring software, and a national registry and management system of patient-radiation-dose is needed to implement radiological optimization through diagnostic reference levels. This management system must work in agreement with the "Institute for Quality Management of Nuclear Medicine", and must take into account the medical reality of Korea, such as low medicine fee, in order to implement reasonable radiological justification and optimization.
Humans ; Neoplasms/diagnosis/radiotherapy ; Positron-Emission Tomography ; *Practice Guidelines as Topic ; Radiation Exposure/*standards ; Radiation Protection ; Radiopharmaceuticals/chemistry/therapeutic use ; Reference Values ; Republic of Korea ; Societies, Scientific ; Tomography, X-Ray Computed

Positron emission tomography (PET) using 2-deoxy-2-[18F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.
Animals ; Brain/*metabolism/radionuclide imaging ; Fluorodeoxyglucose F18/*diagnostic use ; Frontal Lobe/metabolism/radionuclide imaging ; Harderian Gland/metabolism/radionuclide imaging/*surgery ; Mice ; Mice, Inbred BALB C ; Neuroimaging/standards/*veterinary ; Positron-Emission Tomography/*veterinary ; Radiopharmaceuticals/*diagnostic use

Whole body integrated magnetic resonance imaging (MR)/positron emission tomography (PET) imaging systems have recently become available for clinical use and are currently being used to explore whether the combined anatomic and functional capabilities of MR imaging and the metabolic information of PET provide new insight into disease phenotypes and biology, and provide a better assessment of oncologic diseases at a lower radiation dose than a CT. This review provides an overview of the technical background of combined MR/PET systems, a discussion of the potential advantages and technical challenges of hybrid MR/PET instrumentation, as well as collection of possible solutions. Various early clinical applications of integrated MR/PET are also addressed. Finally, the workflow issues of integrated MR/PET, including maximizing diagnostic information while minimizing acquisition time are discussed.
Coordination Complexes/chemistry/diagnostic use ; Heart/radiography ; Humans ; *Magnetic Resonance Imaging ; Neoplasm Metastasis ; Neoplasm Staging ; Neoplasms/pathology/radiography ; *Positron-Emission Tomography ; Radiopharmaceuticals/diagnostic use ; Tomography, X-Ray Computed ; Whole Body Imaging/*standards/*trends