• The Korean Journal of Nuclear Medicine
• /
• v.33 no.3
• /
• pp.262-272
• /
• 1999

Purpose: Interictal F-18-fluorodeoxyglucose (FDG) PET and ictal Tc-99m-HMPAO SPECT are found to be useful in localizing epileptogenic zones in neocortical lateral temporal or frontal lobe epilepsy. We investigated whether interictal F-18-FDG PET or ictal Tc-99m-HMPAO SPECT was useful to find epileptogenic Bones in occipital lobe epilepsy (OLE). Materials and Methods: We reviewed patterns of hypometabolism in interictal F-18-FDG PET and of hyperperfusion in ictal Tc-99m-HMPAO SPECT in 17 OLE patients (mean age=$27{\pm}6.8$ year, M:F= 10:7, injection time= $30{\pm}17$ sec). OLE was diagnosed based on invasive electroencephalography (EEG) study, surgery and post-surgical outcome (Engel class I in all for average 14 months). Results: Epileptogenic zones were correctly localized in 9 (60%) out of 15 patients by interictal F-18-FDG PET. Epiletogenic hemispheres were correctly lateralized in 14 patients (93%). By ictal Tc-99m-HMPAO SPECT, epileptogenic hemispheres were correctly lateralized in 13 patients (76%), but localization was possible only in 3 patients (18%). Among patients who showed no abnormality with MR imaging and no correct localization with ictal Tc-99m-HMPAO SPECT, interictal F-18-FDG PET was helpful in 2 patients. Conclusion: Ictal Tc-99m-HMPAO SPECT was helpful in lateralization but not in localization in OLE. Interictal F-18-FDG PET was helpful for localization of epileptogenic zones even in patients with ambiguous MR or ictal SPECT findings.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.3
• /
• pp.247-251
• /
• 2007

A 38-year-old man who was diagnosed with malignant paraganglioma underwent computed tomography (CT) and I-131 metaiodobenzylguanidine (MIBG) san. CT showed extensive lymph node enlargement in right iliac area and retroperitoneum with severe hydronephrosis and mass on posterior bladder wall. However, I-131 MIBG scan didn't showed abnormal uptake. He also underwent F-18 fluorodeoxyglucose (FDG) positron emisson tomography/CT for localizing accurate tumor site. F-18 FDG PET/CT showed multiple metastases of left supraclavicular, hilar, mediastinal para-aortic, inguinal, right iliac lymph nodes, lung, vertebrae, and pelvis. There are a few reports showing that the F-18 FDG PET/CT is helpful for staging and localizing tumor site of patients who are diagnosed with negative on the MIBG scans. Thus, we report a case with paraganglioma which showed negative I-131 MIBG scan, but revealed multiple intense hypermetabolic foci in F-18 FDG PET/CT.

• The Journal of the Korean bone and joint tumor society
• /
• v.14 no.2
• /
• pp.86-94
• /
• 2008

$^{18}F$-FDG PET/CT has led to advancement in diagnostic imaging, providing correlation of both physiology and anatomic information, and to new and innovative ways to utilize PET/CT imaging for the evaluation of musculoskeletal tumors. Recently, the most widely utilized musculoskeletal application of PET/CT imaging is for the detection and characterization of bone metastases, staging and restaging of primary malignant bone tumors and soft tissue sarcomas. And it is also useful in evaluating response to therapy for malignant musculoskeletal tumors and in detecting local recurrences or distant metastases during follow up. The future likely holds even more unique and potentially quite useful applications of PET/CT imaging for primary bone and soft tissue tumors. This article will review the useful applications of $^{18}F$-FDG PET/CT imaging for evaluating musculoskeletal tumors.

• Korean Journal of Head & Neck Oncology
• /
• v.26 no.2
• /
• pp.178-182
• /
• 2010

서 론 : 두경부암의 예후에 가장 중요한 인자는 진단시 병기와 치료 후 재발의 유무이다. 따라서, 재발 병변을 조기에 발견하는 것이 매우 중요하다. 본 연구에서는 두경부암 환자의 추적 관찰에서 $^{18}F$-FDG PET/CT의 유용성에 대해 알아보고자 하였다. 대상 및 방법 : 2004년 4월부터 2008년 8월까지 고려대 안암병원에서 두경부암으로 치료를 완료한 후 추적관찰이 가능하였던 88 예의 환자를 대상으로 하였다. 환자는 본원의 두경부암 추적관찰 양식에 따라 술 후 6, 12개월째 $^{18}F$-FDG PET/CT를 시행하였으며, 원발부위 및 경부 재발, 원격전이와 중복암의 진단에 있어 $^{18}F$-FDG PET/CT의 민감도, 특이도, 양성예측율, 음성예측율을 평가하였고, 기존의 추적관찰 방법과 이를 비교하였다. 결 과 : 원발부위 재발의 진단에 있어 민감도, 특이도, 양성예측율, 음성예측율은 각각 95%, 97%, 90%, 98% 였다. 경부전이 재발의 진단에 있어서는 각각 94%, 98%, 83%, 99%였으며, 원격전이 및 이차암 진단에 있어서는 94%, 100%, 100%, 99%였다. 원발부위 재발은 고식적인 진단 방법, 원격전이와 이차암은 $^{18}F$-FDG PET/CT가 진단에 의미있게 유리하였다. 결 론 : $^{18}F$-FDG PET/CT는 두경부암의 추적관찰 과정에서 재발 여부를 판정하는데 있어 매우 유용하며, 특히 원격전이 및 이차암의 발견에 있어 유용하다. 그러나, 위양성 및 위음성의 가능성으로 고식적인 진단 방법과 병행해야 진단의 효과를 높힐 것으로 생각된다.

• Journal of Radiation Protection and Research
• /
• v.38 no.3
• /
• pp.157-165
• /
• 2013

To determine the factors affecting the external radiation dose rates of patients undergoing PET-MRI examinations and to assess the trends of these differences, we measured the changes in the dose rates of $^{18}F$-FDG during a set period of time for each body region. Consistent with theoretical predictions, the dose rate decreased over time in patients undergoing PET-MRI examinations. Furthermore, immediately after the $^{18}F$-FDG injection, the dose rate in the chest region was the highest, followed by the abdominal region, the head region, and the foot region. The dose rate decreased drastically as time passed, by 2.47-fold, from $339.23{\pm}74.70mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection to $102.71{\pm}26.17mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. In the foot region, there were no significant changes over time, from $32.05{\pm}20.23mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection, to $23.89{\pm}9.14mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. The dose rate is dependent on the individual characteristics of the patient, and differed depending on the body region and time point. However, the dose rates were higher in patients who had a lower body weight, shorter stature, fewer urinations, lower fluid intake, and history of diabetes mellitus. To decrease radiation exposure, it is difficult or impossible to change factors inherent to the patient, such as sex, age, height, body weight, obesity, and history of diabetes mellitus. However, factors which can be changed, such as the $^{18}F$-FDG dose, fasting time, fluid intake, number of urinations, and contrast agent dose can be controlled to minimize the external radiation exposure of the patient.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.20 no.2
• /
• pp.42-45
• /
• 2016

Purpose Neuracep is used to other diagnostic evaluations of the brain to estimate beta-amyloid neuritic plaque density in adult patients with cognitive impairment and inspected cognitive impairment. $^{18}F-Florbetaben$ specially has moderate lipophilicity and property of the added ethanol. It is the subject of interest of the patient pain and residual activity after injecting. Our study is effective injection method of the radiopharmaceutical and patient care. So it is for the highest quality image. Materials and Methods Patients were targeted 70 subjects, it was injected mean $259{\pm}74MBq$ to the patients ($^{18}F-FDG$: 20 subjects, $^{18}F-FP-CIT$: 20 subjects, $^{18}F-Florbetaben$: 30 subjects). After injection (reflusing 2 times, reflusing 3 times) using a 3-way set, it measured the residual activity. When injecting $^{18}F-Florbetaben$, we evaluated the effective injection methods(3-way set method and heparin cap method). The average residual activity after the injection was compared using a statistical analysis of SPSS 12.0(ANOVA, t-test analysis). Also, elemental analysis was performed on $^{18}F-Florbetaben$ by GC (Gas Chromatography). Results When reflusing 2 times measured residual activity as follows ($^{18}F-FDG$: 1.48 MBq, $^{18}F-FP-CIT$: 7.4 MBq, $^{18}F-Florbetaben$: 32.6 MBq). And when reflusing 3 times measured residual activity as follows ($^{18}F-FDG$: 1.85 MBq, $^{18}F-FP-CIT$: 3.7 MBq, $^{18}F-Florbetaben$: 36.3 MBq). There was a significant difference when reflusing 2 times(P < 0.05) and reflusing 3 times (P < 0.05). But when reflusing 3 times, there was no significant difference relation FDG and FP-CIT (P > 0.05). $^{18}F-Florbetaben$ Residual activity according to the injection method was a significant difference (P < 0.05). GC analysis results were measured ethanol: 207665 ppm and acceton: 377.4 ppm. Conclusion $^{18}F-Florbetaben$ was high residual activity compared to FDG and FP-CIT. Heparin cap method was effective when $^{18}F-Florbetaben$ was injected. $^{18}F-Florbetaben's$ ethanol component analysis was highly measured. So it is recommended that inject to 6 sec/ml or more in order to reduce the pain.

• Nuclear Medicine and Molecular Imaging
• /
• v.43 no.3
• /
• pp.240-244
• /
• 2009

F-18 FDG PET is a metabolic imaging modality that is efficacious in staging and assessment of treatment response for variety of lymphomas. We report usefulness of F-18 FOG PET/Cl in evaluating severity of the disease and response to therapy in a patient with subcutaneous panniculitis- like T-cell lymphoma (SPTCL). Here we describe a case of SPTCL in 24-year-old man who had wide spread firm and tender nodular lesions with increased F-18 FOG uptake. After chemotherapy follow up F-18 FDG PET/CT image shows disseminated malignancy and then the patient died with hemophagocytic syndrome. This report suggests that F-18 FDG PET/CT may be useful in determining disease activity at the time of initial diagnosis, after treatment, and evaluating a suspected outcome of SPTCL.

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

• Clinical and Experimental Pediatrics
• /
• v.57 no.6
• /
• pp.278-286
• /
• 2014

Purpose: To evaluate the potential utility of $^{123}I$-metaiodobenzylguanine ($^{123}I$-MIBG) scintigraphy and $^{18}F$-fluorodeoxyglucose ($^{18}F$-FDG) positron emission tomography (PET) for the detection of primary and metastatic lesions in pediatric neuroblastoma (NBL) patients, and to determine whether $^{18}F$-FDG PET is as beneficial as $^{123}I$-MIBG imaging. Methods: We selected 8 NBL patients with significant residual mass after operation and who had paired $^{123}I$-MIBG and $^{18}F$-FDG PET images that were obtained during the follow-up. We retrospectively reviewed the clinical charts and the findings of 45 paired scans. Results: Both scans correlated relatively well with the disease status as determined by standard imaging modalities during follow-up; the overall concordance rates were 32/45 (71.1%) for primary tumor sites and 33/45 (73.3%) for bone-bone marrow (BM) metastatic sites. In detecting primary tumor sites, $^{123}I$-MIBG might be superior to $^{18}F$-FDG PET. The sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 96.7% and 70.9%, respectively, and their specificity were 85.7% and 92.8%, respectively. $^{18}F$-FDG PET failed to detect 9 true NBL lesions in 45 follow-up scans (false negative rate, 29%) with positive $^{123}I$-MIBG. For bone-BM metastatic sites, the sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 72.7% and 81.8%, respectively, and the specificity were 79.1% and 100%, respectively. $^{123}I$-MIBG scan showed higher false positivity (20.8%) than $^{18}F$-FDG PET (0%). Conclusion: $^{123}I$-MIBG is superior for delineating primary tumor sites, and $^{18}F$-FDG PET could aid in discriminating inconclusive findings on bony metastatic NBL. Both scans can be complementarily used to clearly determine discrepancies or inconclusive findings on primary or bone-BM metastatic NBL during follow-up.

• Molecular & Cellular Toxicology
• /
• v.3 no.3
• /
• pp.198-207
• /
• 2007

[ $^{18}F$ ]-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) scan has been found to reflect tumor aggressiveness and prognosis in various types of cancer. In this study, the gene expression profiles of glial tumors were evaluated to determine whether glial tumors with high $^{18}F$-FDG uptake have more aggressive biological potential than with low uptake. Surgical specimens were obtained from the 12 patients with glial tumors (4 males and 8 females, age range 42-68 years). The tumor samples were divided into two groups based on the $^{18}F$-FDG uptake PET scan findings: high $^{18}F$-FDG uptake (n=4) and low $^{18}F$-FDG uptake (n=8). The pathological tumor grade was closely correlated with the $^{18}F$-FDG uptake pattern: Glial tumors with high $^{18}F$-FDG uptake were pathologically Edmondson-Steiner grade III, while those with low uptake were grade II. The total RNA was extracted from the frozen tissues of all glial tumors (n=12), and adjacent non-cancerous tissue (n=3). The gene expression profiles were evaluated using cDNA microarray. The glial tumors with high $^{18}F$-FDG uptake showed increase expression of 15 genes compared to those with low uptake (P<0.005). Nine genes were down-regulated. Gene expression is closely related to cell survival, cell-to-cell adhesion or cell spreading; therefore, glial tumors with high $^{18}F$-FDG uptake appear to have more aggressive biological properties than those with low uptake.