• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.395-401
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• 2009

Purpose: We evaluated $^{18}F$-FDG PET/CT findings in initially diagnosed adenoid cystic carcinoma (ACC) of the head and neck in association with pathological subtype, staging, uptake comparison with squamous cell carcinoma (SqCC) and prognosis. Materials and Methods: The subjects were 16 patients with initially diagnosed ACC of head and neck who underwent pretreatment $^{18}F$-FDG PET/CT. Histological subtype (solid pattern vs. tubular/cribriform pattern), $SUV_{max}$ of size-matched SqCC of the head and neck as control group, disease-free survival (DFS) were compared with the $SUV_{max}$ of ACC of the head and neck. Results: Of total 16 patients, 6 had solid pattern and the remaining 10 had tubular/cribriform pattern. The $SUV_{max}$ were significantly higher in solid pattern group than in tubular/cribriform pattern group ($6.7{\pm}3.2$ vs. $4.2{\pm}0.9$, p=0.03). PET/CT found unexpected distant metastasis in 18.7% of patients (3/16) and changed the therapeutic plan in those patients. The $SUV_{max}$ of ACC was significantly lower than that of size-matched SqCC ($5.1{\pm}2.4$ vs. $13.6{\pm}6.0$, p<0.001). DFS was not significantly different according to the histological subtype. In contrast, patients with high $^{18}F$-FDG uptake ($SUV_{max}$ ${\geq}$6.0) had significantly shorter DFS than those with low $^{18}F$-FDG uptake ($SUV_{max}$ <6.0). Conclusion: $^{18}F$-FDG uptake of ACC of the head and neck is significantly associated with histological subtype and DFS. $^{18}F$-FDG PET/CT may be useful for detecting unexpected metastasis. Since $^{18}F$-FDG uptake of tubular/cribriform ACC compared with SqCC is relatively low, it is necessary to interpret PET images carefully in patients without alleged ACC.

• Journal of Biomedical Engineering Research
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• v.35 no.3
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• pp.68-74
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• 2014

Recent research on mild cognitive impairment (MCI) has shown that cognitive and memory decline in this disease is accompanied by disruptive changes in the brain functional network. However, there have been no graph-theoretical studies using $^{11}C$-PIB PET data of the Alzheimer's Disease or mild cognitive impairment. In this study, we acquired $^{18}F$-FDG PET and $^{11}C$-PIB PET images of twenty-four normal aging control participants and thirty individuals with MCI from ADNI (Alzheimer's Disease Neuroimaging Initiative) database. Brain networks were constructed by thresholding binary correlation matrices using graph theoretical approaches. Both normal control and MCI group showed small-world property in $^{11}C$-PIB PET images as well as $^{18}F$-FDG PET images. $^{11}C$-PIB PET images showed significant difference between NC (normal control) and MCI over large range of sparsity values. This result will enable us to further analyze the brain using established graph-theoretical approaches for $^{11}C$-PIB PET images.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.499-504
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• 2009

F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET/CT) plays an important role in diagnosis of malignant tumors and adds to conventional imaging in the staging of pertoneal carcinomatosis. However, false positive cases resulting from benign disease such as tuberculosis may occur. We report two cases of peritoneal tuberculosis on F-18 FDG PET/CT which showed multiple hypermetabolic foci in the mesentery and peritoneum with increased serum cancer antigen 125 (CA 125). Subsequent F-18 FDG PET/CT showed a disappearance of pathologic uptake following treatment with anti-tuberculosis drugs.

• The Korean Journal of Nuclear Medicine
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• v.39 no.4
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• pp.263-265
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• 2005

A 25 years old male patient with Hodgkin's disease, considered as complete remission, underwent $^{18}F$-FDG whole body PET/CT. $^{18}F$-FDG whule body PET/CT showed unexpected hypermetabolic nodule in left quadratus femoris muscle suggesting local recurrence. Subsequent MRI also revealed well-enhancing nodular lesion with intermediate and high signal intensity on T1WI and T2WI, respectively. The lesion was confirmed as nodular fasciitis by pathologic examination of the excited specimen.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.6-13
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• 2008

Head and neck cancer is the sixth most common type of human cancer worldwide. Squamous cell carcinoma is the most common cancer of the head and neck. Since $^{18}F-FDG$ PET is very sensitive to detecting squamous cell carcinoma, it has been widely used in patients with head and neck cancers for initial staging, management of recurrent cancers, and therapeutic monitoring. According to clinical research data, $^{18}F-FDG$ PET is expected to be a very helpful diagnostic tool in the management of head and neck cancer.

• The Korean Journal of Nuclear Medicine
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• v.35 no.3
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• pp.131-141
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• 2001

Purpose: We evaluated the sensitivity of the F-18 FDG PET by visual assessment and statistical parametric mapping (SPM) analysis for the localization of the epileptogenic zones in frontal lobe epilepsy. Materials and Methods: Twenty-four patients with frontal lobe epilepsy were examined. All patients exhibited improvements after surgical resection (Engel class I or II). Upon pathological examination, 18 patients revealed cortical dysplasia, 4 patients revealed tumor, and 2 patients revealed cortical scar. The hypometabolic lesions were found in F-18 FDG PET by visual assessment and SPM analysis. On SPM analysis, cutoff threshold was changed. Results: MRI showed structural lesions in 12 patients and normal results in the remaining 12. F-18 FDG PET correctly localized epileptogenic zones in 13 patients (54%) by visual assessment. Sensitivity of F-18 FDG PET in MR-negative patients (50%) was similar to that in MR-positive patients (67%). On SPM analysis, sensitivity decreased according to the decrease of p value. Using uncorrected p value of 0.05 as threshold, sensitivity of SPM analysis was 53%, which was not statistically different from that of visual assessment. Conclusion: F-18 FDG PET was sensitive in finding epileptogenic zones by revealing hypometabolic areas even in MR-negative patients with frontal lobe epilepsy as well as in MR-positive patients. SPM analysis showed comparable sensitivity to visual assessment and could be used as an aid in the diagnosis of epileptogenic zones in frontal lobe epilepsy.

• 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.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.19-27
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• 2002

The annual incidence of primary brain tumors is 7-19 cases per 100,000 people. The unique capacity of visualizing biochemical processes allows PET to determine functional metabolic activities of the brain tumors. Like other malignant tumors, F-18 FDG has been used commonly in the imaging of brain tumors. FDG PET is valuable in grading malignancy, predicting prognosis, monitoring treatment, differentiating tumor recurrence from radiation necrosis, and detecting primary lesion in metastatric brain tumors. Among amino acids labeled with positron emitters, C-11 methionine is used clinically. Tumor delineation is much better with methionine PET than with FDG PET. Low grade gliomas, in particular, are better evaluated with methionine than with FDG. PET opens another dimension in brain tumor imaging. PET imaging has clearly entered the clinical area with a profound impact on patient care in many indications.

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

• 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.