• Journal of Yeungnam Medical Science
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• v.38 no.2
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• pp.95-106
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• 2021

Infections involving the heart are becoming increasingly common, and a timely diagnosis of utmost importance, despite its challenges. F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is a recently introduced diagnostic tool in cardiology. This review focuses on the current evidence for the use of FDG PET/CT in the diagnosis of infective endocarditis, cardiac implantable device infection, left ventricular assist device infection, and secondary complications. The author discusses considerations when using FDG PET/CT in routine clinical practice, patient preparation for reducing physiologic myocardial uptake, acquisition of images, and interpretation of PET/CT findings. This review also functions to highlight the need for a standardized acquisition protocol.

• Dementia and Neurocognitive Disorders
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• v.17 no.3
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• pp.90-99
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• 2018

Background and Purpose: To explore anatomic substrate of specific wandering patterns in patients with Alzheimer's disease (AD) by performing positron emission tomography with $^{18}F$ fluorodeoxyglucose positron emission tomography (FDG PET). Methods: Drug-naïve AD patients with wandering (n=80) and without wandering (n=262) were recruited. First, the specific pattern of wandering type was operationally classified according to specific wandering score and clinical assessment. Second, brain FDG PET was performed and fluorodeoxyglucose (FDG) uptake differences of specific brain regions according to wandering patterns were compared to those of non-wanderers. Results: In patients with pacing pattern, FDG PET showed significant lower FDG uptake in both middle cingulum and left putamen cluster compared to non-wanderers. The right precuneus and supplementary motor area in patients with random pattern and left calcarine sulcus, right calcarine sulcus, right middle cingulum, and right post central gyrus in patients with lapping pattern had significantly lower FDG uptake compared to non-wanderers. Conclusions: This study showed that wandering in patients with AD had three distinct patterns. These specific patterns showed significant lower FDG uptake in specific brain areas compared to non-wanderers.

• The Korean Journal of Nuclear Medicine
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• v.38 no.6
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• pp.481-485
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• 2004

Lung cancer has become a leading cause of cancer death in Korea. Accurate staging of non-small cell lung cancer (NSCLC) is essential to the ability to offer a patient the most effective available treatment and the best estimate of prognosis. PET with F-18 fluorodeoxyglucose (FDG) is indicated for the nodal staging of NSCLC and detection of distant metastases. Use of PET for mediastinal staging should not be relied on as a sole staging modality, and positive findings should be confirmed by mediastinoscopy. FDG PET avoids futile surgery by a more accurate selection of patients, especially by the detection of unexpected distant metastases.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.505-507
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• 2009

A 60-year-old woman, who had non-small-cell lung cancer (NSCLC) in left lower lobe underwent brain F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for evaluation of cerebral metastasis. On follow-up FDG-PET/CT, only hypometaolic lesion was detected and progressed in right frontal lobe at 6 months and 10 months, later. Hypermetabolic metastasis was not detected even at last scan time of FDG-PET/CT. Brain MRI showed brain metastasis in right frontal lobe. As might be expected, the physician should take cerebral metastasis into consideration even though there is only hypometabolic change on subsequent FDG-PET/CT in patients with NSCLC.

• Journal of Korean Neurosurgical Society
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• v.49 no.5
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• pp.278-283
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• 2011

Objective : The purpose of this study was to evaluate whether $^{18}F$-fluorodeoxyglucose positron emission tomography (FOG-PET) can be used to assess the therapeutic response of brain abscess. Methods : A study was conducted on 10 consecutive patients with brain abscess, Magnetic resonance imaging (MRI) with diffuse-weighted imaging (DWI) was performed at 3 and 6 weeks after surgical treatment and intravenous antibiotics therapy and FOG-PET at 6 weeks after treatment. The extent of the abscess, signal changes on MRI, and FOG-PET standardized uptake values were analyzed and correlated with the response to therapy. Results : Aspiration or craniotomy with excision of the abscess followed by intravenous antibiotics for 6-8 weeks resulted in good recovery with no recurrence. In 10 patients, two had low signal intensity on the DWI; one had no uptake on FOG-PET imaging after 6 weeks antibiotics and discontinued intravenous treatment, but the other patient had diffuse, increased uptake on FOG-PET imaging after 6 weeks antibiotics and underwent an additional 2 weeks of intravenous antibiotics. The remaining eight patients had high signals on the DWI. Four had no uptake on FOG-PET imaging and the treatment period varied from 6 to 8 weeks (mean, 6.75 weeks). Among the other four patients, FOG was accumulated in a diffuse or local area corresponding to a high signal area within the DWI and 2 weeks of intravenous antibiotics was added. Conclusion : MRI plus FOG-PET improved the accuracy of assessing therapeutic responses to antibiotics treatment of brain abscess and aided in optimizing therapy.

• Journal of the Korean Society of Radiology
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• v.7 no.5
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• pp.365-369
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• 2013

Intravenous injection is administered with radioactive medical isotopes to detect disease on Positron Emission Tomography (PET). In this case, typically, $^{18}FDG$ (Fluorodeoxyglucose) is used as a radioactive medicine. Cassette equipment is needed to synthesize deoxyglucose with $^{18}F$, produced by medical cyclotron. Production of radioactive medicine creates a lot of radiation, thus Hot Cell is used to shield a secondary radiation. We measured the radiation dosage flowing out of the hot cell during synthesis of $^{18}FDG$ or distribution. The purpose of this study is to provide the information of radiation dosage regarding the occupational exposure that unintentionally occurs during the synthesis of $^{18}FDG$. In conclusion, we confirmed the radiation dosage out of the hot cell during the $^{18}FDG$ synthesis. Especially, we observed that the radiation flowed out through the lead window, attached as a view port. Thus, it is considered that the improvement of a lead window is necessary in order to decrease the occupational exposure during the $^{18}FDG$ synthesis.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.361-362
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• 2009

We present a patient with high $^{18}$F-fluorodeoxyglucose (FDG) uptake detected in a neurofibroma that was confused with sarcomatous transformation on a positron emission tomography/computed tomography (PET/CT) scan. A 39-year-old male patient with a 20-year history of neurofibromatosis-1 (NF-1) performed FDG PET/CT scan for the evaluation of lesions with sarcomatous transformation. The FDG PET/CT images demonstrated varying degrees of increased FDG uptake in the multiple nodules throughout whole body. The left pelvic mass with the highest FDG uptake had a maximum standardized uptake values (maxSUV) 5.0 and surgical resection was performed. Histological analysis confirmed the presence of a benign neurofibroma infiltrated with inflammatory cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.5
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• pp.462-469
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• 2000

Positron Emission Tomography(PET) is a new diagnostic method that can create functional images of the distribution of positron emitting radionuclides, which when administered intravenously in the body, makes possible anatomical and functional analysis by quantity of biochemical and physiological process. After genetic and biochemical changes in initial stage, malignant tumor undergoes functional changes before undergoing anatomical changes. So, early diagnosis of malignant tumors by functional analysis with PET can be achieved, replacing traditional anatomical analysis, such as computed tomography(CT) and magnetic resonance image(MRI), etc. Similarly, PET can identify malignant tumor without confusion with scar and fibrosis in follow up check. In the Korea Cancer Center Hospital(KCCH) from October 1997 to September 1999, clinical study was performed in 79 cases that underwent 89 times PET evaluation with [18F]-Fluorodeoxyglucose for diagnosis of oral and maxillofacial tumors, and the data was analysed by Bayesian $2{\times}2$ Classification Table. The results were as follows : Evaluation for initial diagnosis with FDG-PET (P<0.005) 1. Agreement rate or accuracy rate is 88.9%. 2. Sensitivity is 95.2%, and specificity 66.7%. 3. Positive predictive rate is 90.9%, and negative predictive rate 80.0%. 4. In consideration of tumor stage, diagnostic rate in less than stage II was 90% and in greater than stage III 100%. 5. In consideration of tumor size, diagnostic rate in less than T2 was 92.3% and in greater than T3 100%. After primary treatment, evaluation for follow up check with FDG-PET (P < 0.001) 1. Agreement rate or accuracy rate is 85.4%. 2. Sensitivity is 87.5%, and specificity 82.4%. 3. Positive predictive rate is 87.5%, and negative predictive rate 82.4%. 4. In 24 recurred cases, 6 had distant metastasis, and 5 of them were diagnosed with FDG-PET, resulting in diagnostic rate of FDG-PET of 83.3%. From the above results, Positron Emission Tomography with [18F]- Fluorodeoxyglucose appears to be more sensitive and accurate for detecting the presence of oral and maxillofacial tumors, and has various clinical applications such as early diagnosis of tumor in initial and follow up check and detection of distant metastasis.

• Journal of Gastric Cancer
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• v.18 no.3
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• pp.218-229
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• 2018

Purpose: This study investigated whether the metabolic avidity of primary tumors and/or metastatic lymph nodes (LNs) measured by $^{18}F$-fluorodeoxyglucose ($^{18}F-FDG$) positron emission tomography/computed tomography (PET/CT) was related to survival after surgery in patients with advanced gastric cancer (AGC). Materials and Methods: One hundred sixty-eight patients with AGC who underwent preoperative $^{18}F-FDG$ PET/CT and curative resection were included. The $^{18}F-FDG$ avidity of the primary gastric tumor and LNs was determined quantitatively and qualitatively. The diagnostic performance of $^{18}F-FDG$ PET/CT was calculated, and the prognostic significance of $^{18}F-FDG$ avidity for recurrence-free survival (RFS) and overall survival (OS) was assessed. Results: In all, 51 (30.4%) patients experienced recurrence, and 32 (19.0%) died during follow-up (median follow-up duration, 35 months; range, 3-81 months); 119 (70.8%) and 33 (19.6%) patients showed $^{18}F-FDG$-avid primary tumors and LNs, respectively. $^{18}F-FDG$ PET/CT showed high sensitivity (73.8%) for the detection of advanced pathologic T ($pT{\geq}3$) stage and high specificity (92.2%) for the detection of advanced pN (${\geq}2$) stage. $^{18}F-FDG$ avidity of LNs was significantly associated with RFS (P=0.012), whereas that of primary tumors did not show significance (P=0.532). Univariate and multivariate analyses revealed that $^{18}F-FDG$ avidity of LNs was an independent prognostic factor for RFS (hazard ratio=2.068; P=0.029). Conclusions: $^{18}F-FDG$ avidity of LNs is an independent prognostic factor for predicting RFS. Preoperative $^{18}F-FDG$ PET/CT can be used to determine the risk and prognosis of patients with AGC after curative resection.

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