• Nuclear Medicine and Molecular Imaging
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• v.42 no.4
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• pp.333-336
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• 2008

A 52-year-old woman with a history of general weakness, fatigue, weight loss, elevated serum levels of liver transaminase enzyme for three months underwent an F-18 FDG PET/CT scan to evaluate a cause of the hepatosplenomegaly found on abdominal ultrasonography. Initial PET/CT revealed markedly enlarged liver and spleen with intense FDG uptake. Otherwise, there were no areas of abnormal FDG uptake in whole body image. Histological evaluation by a hepatic needle biopsy demonstrated diffuse large B cell type lymphoma and final diagnosis for this patient was hepatosplenic B-cell lymphoma. She received five cycles of CHOP chemotherapy, and second PET/CT scan was followed after then. Follow-up PET-CT revealed normal sized liver with disappearance of abnormal FDG uptake. Hepatosplenic B-cell lymphoma is relatively rare and mostly presents as single or multiple nodules.1,2 Diffuse type hepatosplenic lymphoma is extremely rare and poorly recognized entity.3 The diagnosis is very difficult and complicated by the presence of misleading symptoms.4 In this rare hepatosplenic B-cell lymphoma case, F-18 FDG PET/CT scan provided a initial diagnostic clue of hepatosplenic lymphoma and an accurate chemotherapy response.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.172-176
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• 2008

FDG PET has been used as a diagnostic tool for localization of seizure focus for last 2-3 decades. In this article, the clinical usefulness of FDG PET in the management of patients with epilepsy has been reviewed, which provided the evidences to justify the medicare reimbursement for FDG PET in management of patients with epilepsy. Literature review demonstrated that FDG PET provides an important information in localization of seizure focus and determination whether a patients is a surgical candidate or not. FDG PET has been reported to have high diagnostic performance in localization of seizure focus in neocortical epilepsy as well as temporal lobe epilepsy regardless of the presence of structural lesion on MRI. Particularly, FDG PET can provide the additional information when the results from standard diagnositic modality such as interictal or video-monitored EEG, and MRI are inconclusive or discordant, and make to avoid invasive study. Furthermore, the presence of hypometabolism and extent of metabolic extent has been reported as an important predictor for seizure free outcome. However, studies suggested that more accurate localization and better surgical outcome could be expected with multimodal approach by combination of EEG, MRI, and functional studies using FDG PET or perfusion SPECT rather than using a single diagnostic modality in management of patients with epilepsy. Complementary use of FDG PET in management of epilepsy is worth for good surgical outcome in epilepsy patients.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.5
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• pp.414-418
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• 2008

The role of positron emission tomography (PET) with F-18 fluorodeoxyglucose (F-18 FDG) in the diagnosis of hepatocellulcar carcinoma (HCC) has been limited because of a variable FDG uptake in HCC. However, the usefulness of PET/CT for detecting extrahepatic metastasis and monitoring of the treatment response in HCC has been reported. A 55-year-old man with a hepatitis B surface antigen-positive, was admitted to our hospital due to dyspnea, general weakness and body weight loss for one month. Chest X-ray showed multiple reticulo-nodular densities on both lower lung fields, which implies metastatic lesions. F-18 FDG PET/CT revealed consecutively intense hypermetabolic mass in right hepatic lobe, inferior vena cava and right atrium. We report a case of HCC with IVC and right atrium invasion identified by F-18 FDG PET/CT.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.5
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• pp.257-262
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• 2006

Purpose: The standard protocol using large volume of oral contrast media may cause gastrointestinal discomfort and contrast-related artifacts in PET/CT. The aim of this study was to evaluate the usefulness of low dose oral contrast in $^{18}F-FDG$ PET/CT. Materials and Methods: We retrospectively reviewed the whole-body PET/CT images in a total of 435 patients. About 200 ml of oval contrast agent (barium sulfate) was administered immediately before injection of $^{18}F-FDG$. The FDG uptake of intestines was analyzed by visual and semi- quantitative method on transaxial, coronal and saggital planes. Results: Seventy (16%, 113 sites) of 435 images showed high FDG uptake (peak SUV > 4); 50 (74%, 84 sites) with diffuse and 20 (15%, 29 sites) with focal uptake. The most commonly delivered site of oral contrast media was small bowel (n=27, 39%). On PET/CT images, FDG uptake coexisted with oral contrast media in 26 patients (54%, 38 sites) with diffuse pattern and 9 (45%, 9 sites) with focal pattern, and by sites, those were 38 (45%) and 9 (31%), respectively. In small bowel regions, the proportion of coexistence reached as high as 61% (29/47 sites). A visual analysis of available non-attenuation corrected PET images of 27 matched regions revealed no contrast-related artifact. Conclusion: We concluded that the application of low dose contrast media could be helpful in the evaluation of abdominal uptake in the FDG PET/CT image.

• The Korean Journal of Nuclear Medicine
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• v.39 no.4
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• pp.239-245
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• 2005

Purpose: Hypereosinophilic syndrome (HES) is an infiltrative disease of eosinophils affecting multiple organs including the iung. F-18 2-fluoro-2-deoxyglucose (F-18 FDG) may accumulate at sites of inflammation or injection, making interpretation of whole body PET scan difficult in patients with cancer. This study was to evaluate the PET findings of HES with lung involvement and to find out differential PET features between lung malignancy and HES with lung involvement. Material and Methods: F-18 FDG PET and low dose chest CT scan was performed for screening of lung cancer. light patients who showed ground-glass attenuation (GGA) and consolidation on chest CT scan with peripheral blood eosinophilia werr included in this study. The patients with history of parasite infection, allergy and collagen vascular disease were excluded. CT features and FDG PET findings were meticulously evaluated for the distribution of GGA and consolidation and nodules on CT scan and mean and maximal SUV of abnormalities depicted on F-18 FDG PET scan. In eight patients, follow-up chest CT scan and FDG PET scan were done one or two weeks after initial study. Results: F-18 FDG PET scan identified metabolically active lesions in seven out of eight patients. Maximal SUV was ranged from 2.8 to 10.6 and mean SUV was ranged from 2.2 to 7.2. Remaining one patient had maximal SUV of 1.3. On follow-up FDG PET scan taken on from one to four weeks later showed decreased degree of initially noted FDG uptakes or migration of previously noted abnormal FDG uptakes. Conclusions: Lung involvement in the HES might be identified as abnormal uptake foci on FDG PET scan mimicking lung cancer. Follow-up FDG PET and CT scan for the identification of migration or resolution of abnormalities and decrement of SUV would be of help for the differentiation between lung cancer and HES with lung involvement.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.1
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• pp.69-74
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• 2019

Purpose $^{18}F$-FDOPA using amino acid is particularly attractive for imaging of brain tumors because of the high uptake in tumor tissue and the low uptake in normal brain tissue. But, on the other hand, $^{18}F$-FDG is highly uptake in both tumor tissue and normal brain tissue. The purpose of study is to evaluate comparison of contrasts in $^{18}F$-FDOPA Brain PET/CT and $^{18}F$-FDG Brain PET/CT and to find out optimal scan time by analysis of variation in SUV with the passage of uptake time. Materials and Methods A region of interest of approximately $350mm^2$ at the center of the tumor and cerebellum in 12 patients ($51.4{\pm}12.8yrs$) who $^{18}F$-FDG Brain PET/CT and $^{18}F$-FDOPA Brain PET/CT were examined more than once each. The $SUV_{max}$ was measured, and the $SUV_{max}$ ratio (T/C ratio) of the tumor cerebellum was calculated. In the analysis of SUV, T/C ratio was calculated for each frame after dividing into 15 frames of 2 minutes each using List mode data in 25 patients ($49.{\pm}10.3yrs$). SPSS 21 was used to compare T/C ratio of $^{18}F$-FDOPA and T/C ratio of $^{18}F$-FDG. Results The T/C ratio of $^{18}F$-FDOPA Brain PET/CT was higher than the T/C ratio of $^{18}F$-FDG Brain, and show a significant difference according to a paired t-test(t=-5.214, p=0.000). As a result of analyzing changes in $SUV_{max}$ and T/C ratio, the peak point of $SUV_{max}$ was $5.6{\pm}2.9$ and appeared in the fourth frame (6 to 8 minutes), and the peak of T/C ratio also appeared in the fourth frame (6 to 8 minutes). Taking this into consideration and comparing the existing 10 to 30 minutes image and 6 to 26 minutes image, the $SUV_{max}$ and T/C ratio increased by 0.2 and 0.1 each, compared to the 10 to 30 minutes image for 6 to 26 minutes image. Conclusion From this study, $^{18}F$-FDOPA Brain PET/CT is effective when reading the image, because the T/C ratio of $^{18}F$-FDOPA Brain PET/CT was higher than T/C ratio of $^{18}F$-FDG Brain PET/CT. In addition, in the case of $^{18}F$-FDOPA Brain PET/CT, there was no difference between the existing 10 to 30 minutes image and 6 to 26 minutes image. Through continuous research, we can find possibility of shortening examination time in $^{18}F$-FDOPA Brain PET/CT. Also, we can help physician to accurate reading using additional scan data.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.91-100
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• 2008

Ovarian cancer is often fatal since it is difficult to diagnose early and recurrence is quite frequent despite successful implementation of cytoreductive surgery and chemotherapy, thus exact diagnosis and early detection of recurrence are crucial to patient management. For pre-treatment staging, FDG PET could be helpful in a limited patient group possessing high risks of ovarian cancer. Besides, FDG PET could be recommended to patients with a high suspicion of recurrence i.e. rise of CA-125, especially in cases of conventional diagnostic imaging modalities presenting no evidence of disease because FDG PET provides critical information for treatment planning such as recurrence site or pattern. In order to expand the use of FDG PET to general population at staging or routine surveillance of ovarian cancer, more investigation is needed. The usefulness of FDG PET in evaluating treatment response and prognosis of ovarian cancer has not yet been determined, but it has been reported that FDG PET could evaluate treatment response early and show a close relationship with overall survival. PET/CT has been actively adopted in management of ovarian cancer. Not only in detecting tumor recurrence and evaluating treatment response but also in pre-treatment staging, FDG PET/CT is expected to playa role due to available anatomical information.

• Imaging Science in Dentistry
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• v.44 no.4
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• pp.325-332
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• 2014

A combination of positron emission tomography (PET) with $^{18}F$-labeled fluoro-2-deoxyglucose ($^{18}F$-FDG) and computed tomography ($^{18}F$-FDG-PET/CT) has increasingly become a widely used imaging modality for the diagnosis and management of head and neck cancer. On the basis of both recent literature and our professional experience, we present a set of principles with pictorial illustrations and clinical applications of FDG-PET/CT in the evaluation and management planning of squamous cell carcinoma of the oral cavity and oropharynx. We feel that this paper will be of interest and will aid the learning of oral and maxillofacial radiology trainees and practitioners.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.87-93
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• 2022

[¹⁸F]FDG is known as the most widely used radiopharmaceutical in the imaging field of nuclear medicine worldwide. With the introduction of PET equipment, the demand for [¹⁸F]FDG has increased and the production volume has also increased. However, in order to increase production, the use of ¹⁸F radioisotope must be increased or [¹⁸F]FDG must be synthesized in high yield. Therefore, in order to meet the high yield and purity of radiopharmaceuticals, a radiopharmaceutical automatic synthesizer was required. As the use of [¹⁸F]FDG increased, automated synthesizer manufacturers supplied various types of radiopharmaceutical automated synthesizers to the market. In this study, we developed a commercialized [¹⁸F]FDG radiopharmaceutical automatic synthesizer (sCUBE FDG) using a disposable cassette type that complies with GMP developed by FutureChem, a leading radiopharmaceutical company. We used sCUBE FDG to verify the production process, radiopharmaceutical's quality (radiochemical purity, etc.), and radiochemical yield of [¹⁸F]FDG. As a result of optimizing the automatic synthesis process and synthesizing a total of 30 times, the production time was 35 ± 3 minutes and the average production yield was 65.6%.

• The Korean Journal of Nuclear Medicine
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• v.36 no.3
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• pp.147-154
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• 2002

The role of PET in the diagnosis and management of thyroid cancer is discussed. The major role of F-18 FDG PET is on patients with discordant negative I-131 scan and a positive serum thyroglobulin values. F-18 FDG PET scan localized metastatic sites in I-131 scan-negative thyroid carcinoma patients with high accuracy. F-18 PET is also valuable in medullary thyroid cancer with high calcitonin level. Focal thyroid uptake in patients with non-thyroidal diseas has high likelihood of thyroid cancer.