Jin Sook Ryu

Use of Tc-99m HMPAO leukocyte scans to evaluate bone infection: incremental value of additional SPECT images.

PURPOSE In this study, the diagnostic value of Tc-99m hexamethylpropylene amine oxime (HMPAO) leukocyte scans and the role of additional SPECT in the diagnosis of bone infection were evaluated. MATERIALS AND METHODS The Tc-99m HMPAO leukocyte scans of 37 patients with clinically suspected bone infection were reviewed. The patients were divided into two groups according to the presence of orthopedic implants. Early (4 to 6 hours) and delayed (18 to 20 hours) planar images and early SPECT images were obtained. The final diagnosis of infection was made based on the pathologic, bacteriologic, and surgical data and clinical follow-up. RESULTS Group 1 (25 patients with orthopedic implants) included 15 true-positive, 1 false-negative, 7 true-negative, and 2 false-positive results. Group 2 (12 patients without orthopedic implants) included 7 true-positive, 1 false-negative, and 4 true-negative results. The overall sensitivity of the Tc-99m HMPAO leukocyte scan with SPECT to detect bone infection was 92%, with a specificity rate of 85%. (Group 1: sensitivity, 94%; specificity, 78%. Group 2: 88% and 100% sensitivity and specificity, respectively.) CONCLUSION The Tc-99m HMPAO leukocyte scan is useful in the diagnosis of bone infection, regardless of the presence of orthopedic implants. The additional SPECT images may be helpful to localize the site of infection more accurately.

New automated synthesis of [18F]FP-CIT with base amount control affording high and stable radiochemical yield: a 1.5-year production report

We describe new [(18)F]Fluoropropylcarbomethoxyiodophenyl-nor-tropane ([(18)F]FP-CIT) automatic preparation method by (1) using 2-methyl-2-butanol as [(18)F]fluorination solvent, (2) base amount control to minimize side reaction and (3) salt elution method to elute trapped [(18)F]fluoride. We developed manual synthesis procedures for automatic synthesis application. In this manual synthesis, we trapped [(18)F]F(-) on ion exchange cartridge and eluted with 0.2 M potassium methanesulfonate solution. We have [(18)F]fluorination at 100°C with 2-methyl-2-butanol as protic solvent for [(18)F]fluorination. After high-performance liquid chromatography analysis, we have 69.3±3.2% of [(18)F]F(-) incorporation ratio on the manual synthesis and applied these conditions to automatic preparation with GE TracerLab FX module. After setting-up of automatic synthesis and quality control procedures for clinical procedures, we have routine production of [(18)F]FP-CIT with 86.9±9.5 GBq/2.5 ml of [(18)F]F(-) as initial radioactivity and have 192 productions for 1.5 year. We have 42.5±10.9% of decay corrected radiochemical yields and they were satisfied all quality control procedures and stability to 6 h. New [(18)F]FP-CIT automatic preparation method showed high and reliable radiochemical yield and we could have enough >35 patient doses of [(18)F]FP-CIT from one production.

Hepatobiliary scintigraphy in the assessment of biliary obstruction after hepatic resection with biliary-enteric anastomosis.

Abstract.We investigated the usefulness of hepatobiliary scintigraphy (HBS) for diagnosing biliary obstruction after curative hepatic resection with biliary-enteric anastomosis. The study population consisted of 54 patients who underwent surgery for benign (n=18) or malignant (n=36) biliary disease. We analysed 68 technetium-99m DISIDA scintigrams which were performed at least 1 month after the surgery (median: 9 months). Final diagnosis was made by operative exploration, other invasive radiological studies or clinical and radiological follow-up for at least 6 months after the surgery. Diagnostic accuracy was analysed according to the pretest likelihood of biliary obstruction. There were two total and 15 segmental biliary obstructions. In patients with symptoms of biliary obstruction and abnormal liver function, HBS always allowed correct diagnosis (two instances of total obstruction, seven of segmental obstruction and seven of non-obstruction). Among the patients with non-specific symptoms or isolated elevation of serum alkaline phosphatase, HBS diagnosed segmental biliary obstruction in seven of the eight instances, and non-obstruction in 22 of 23 instances. There were no cases of biliary obstruction and no false-positive results of HBS in 21 instances with no clinical signs or symptoms of biliary obstruction. The diagnostic sensitivity and specificity of HBS for biliary obstruction were 94% (16/17) and 97% (50/51), respectively. In conclusion, HBS is a highly accurate modality for the diagnosis of segmental biliary obstruction during long-term follow-up after hepatic resection with biliary-enteric anastomosis.

A Case of Acute Q Fever Hepatitis Diagnosed by F-18 FDG PET/CT

A 53-year-old man with fever of unknown origin underwent F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) as a workup for a fever of unknown origin. On presentation, he complained of fever, chills, and myalgia. The F-18 FDG PET/CT scan showed diffusely increased uptake of the liver with mild hepatomegaly. A liver biopsy then revealed fibrin-ring granulomas typically seen in Q fever. The patient was later serologically diagnosed as having acute Q fever as the titers for C. burnetii IgM and IgG were 64:1 and 16:1, respectively. He recovered completely following administration of doxycycline. This indicates that F-18 FDG PET/CT may be helpful for identifying hepatic involvement in Q fever as a cause of fever of unknown origin.

An Unusual Case of Anaphylaxis After Fluorine-18-Labeled Fluorodeoxyglucose Injection

Abstract[18F]FDG (fluorine-18 fluoro-2-deoxy-D-glucose) positron emission tomography (PET) is used worldwide for oncologic and neurologic applications. To date, the potential harm caused by [18F]FDG has focused on its radiation exposure effects rather than on its pharmacological effects. While an allergic response in the form of a skin manifestation has been reported after exposure to [18F]FDG, this report describes the first case of hypotension following exposure to this tracer. Here, the development of anaphylaxis after [18F]FDG injection is described.