• The Korean Journal of Nuclear Medicine
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• v.31 no.3
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• pp.372-380
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• 1997

The purpose of this study was to evaluate the usefulness of whole body F-18 FDG PET scan for detecting postoperative recurrence of cancer. One hundred four cancer patients after operation were enrolled(14 brain tumor, 15 head and neck cancer, 23 gynecologic cancer, 16 gastrointestinal cancer, 16 thyroid cancer, and 20 other cancers). Besides conventional images(CI) including CT and MRI, F-18 FDG PET scan was obtained on ECAT EXACT 47 scanner(Siemens-CTI), beginning 60 minutes after injection of 370MBq(10mCi) of F-18 FDG. Regional scan was also obtained with emission image. Transmission images using Ge-68 were carried out for attenuation correction in both whole body and regional images. Findings of PET, and CI were confirmed by pathology or clinical follow up. The sensitivity and specificity of PET for detecting recurrence were 94% and 92%, respectively. Contrarily, the sensitivity and specificity of CI were 78% and 68%. CI results were negative and PET results were positive in 11 cases. The biopsy or clinical follow-up of those cases confirmed recurrence of tumor. False negative cases of CI were frequent in patients with gynecologic cancers. Also we measured the serum concentration of tumor markers in patients with gynecologic cancer(CA125), thyroid cancer(thyroglobulin), and colorectal cancer(CEA). The sensitivity and specificity of tumor markers were 71% and 84%, respectively, We conclude that F-18 FDG PET can be used valuably in detecting recurrent foci of a wide variety of malignancy compared to conventional diagnostic methods.

• Journal of the Korean Society of Radiology
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• v.14 no.4
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• pp.467-475
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• 2020

The purpose of this study is to assess doses to ¹⁸F-FDG, a radioactive drug, during PET examinations, to alleviate anxiety about radiation in patients and carers, to minimize the indiscriminate examination progress caused by medical institution personnel and space clearance problems, and health examination. The dose assessment was measured using a thermo-fluorescent dosimeter (TLD) and an electronic personal dosimeter (EPD) at the location of the cervical (hypothyroid), thorax (heart), and lower abdomen (breeding line) which are the three highest tissue areas of the radiation tissue weighting. In addition, spatial dose rates and radioactivity in urine were measured using GM counters and ion boxes. The results are as follows: First, the personal dosimeter TLD was measured 0.0425±0.0277 mSv in the cervical region, 0.0440±0.0386 mSv in the thorax and 0.0485±0.0436 mSv in the lower abdomen, with little difference in the heart dose depending on radiation sensitivity. The EPD was measured at 0.942±0.141 mSv/h immediately after the cervical position, and 0.192±0.031 mSv/h after 120 minutes. Immediately after the thorax position, 0.516±0.085 mSv/h, 120 minutes later 0.128±0.040 mSv/h. Immediately after the lower abdomen position, 0.468±0.091 mSv/h, and after 120 minutes 0.105±0.021 mSv/h were measured. The spatial dose rate at the GM counter was measured immediately at 0.041±0.005 mSv/h, 120 minutes later at 0.014±0.002 mSv/h. The radioactivity in urine using ion chamber was measured at 0.113±0.24 MBq/cc after 60 minutes and 0.063±0.13 MBq/cc after 120 minutes. As a result, ¹⁸F-FDG should be administered, dose re-evaluated two hours after the PET test is completed, and caregivers should be avoided. In addition, it is deemed necessary to provide patients and carers with sufficient explanations and expected values of exposure dose to avoid reckless testing. It is hoped that the data tested in this study will help patients and families relieve anxiety about radiation, and that the radiation workers' exposure management system and institutional improvements will contribute to the development of medical radiation.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.336-343
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• 2010

Coronary artery CT angiography has short scanning length, the exposure dose is high. Therefore, it is required to study on the organ dose when using MDCT. We compared the differences between the absorbed dose and effective dose in the major organs assessing the absorbed dose in the major organs by 16-MDCT and 64-MDCT in the subjects with coronary artery CT angiography, the same protocol by 16-MDCT and 64-MDCT. As a result, the great orders of absorbed dose when conducting coronary artery CT angiography had been shown as heart, stomach, liver, pancreas, kidney, spleen, large intestine, lung, small intestine, thyroid gland, ovary, bladder, and orbit with the absorbed dose distribution of $0.538{\pm}0.026(Mean{\pm}SD,\;p<0.05)mGy{\sim}71.316{\pm}4.316mGy$ in 16-MDCT, and heart, stomach, pancreas, spleen, liver, kidney, small intestine, large intestine, lung, thyroid gland, ovary, bladder, and orbit with the absorbed dose distribution of $0.87{\pm}0.01mGy{\sim}115.26{\pm}1.59mGy$ in 64-MDCT, demonstrating some different distributions. The exposed doses to the patient per one time scanning with coronary artery CT angiography were $71.316{\pm}4.316mGy$ in 16-MDCT as the absorbed dose based on the heart and $115.26{\pm}1.59mGy$ in 64-MDCT. The effective doses were 7.41 mSv and 12.11 mSv in 16 and 64-MDCT, respectively. Taking into account the results of brain CT with 2.8 mSv that has comparatively large scanning length and size, facial CT 0.8 mSv, chest CT 5.7 mSv, pelvic CT 7.2 mSv, and abdominal and pelvic CT 14.4 mSv, it is very high considering the scanning length of 13 cm limited to the heart for the scanning range.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.3
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• pp.103-108
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• 2017

Kabuki syndrome is a rare congenital disorder that causes multiple birth defects and mental retardation. Mutation of the lysine methyltransferase 2D (KMT2D) gene is the primary cause of Kabuki syndrome. We report a 4-year-old Korean girl diagnosed with Kabuki syndrome based on distinctive facial features (eversion of the lower lateral eyelid, arched eyebrows, depressed nasal tip, prominent ears), skeletal anomalies, short stature, and molecular analysis, which revealed a novel frameshift mutation in the KMT2D gene. A 4-year-old patient had a past history of congenital cardiac malformations (coarctation of the aorta, ventricular septal defect, atrial septal defect, patent ductus arteriosus), subclinical hypothyroidism and dysmorphic features at birth including webbed neck, short fingers, high arched palate, micrognathia and horseshoe kidney. She showed unique facial features such as a long palpebral fissure, long eyelashes, arched eyebrows with sparseness of the lateral third, broad nasal root, anteverted ears, and small mouth. Her facial features suggested Kabuki syndrome, and genetic analysis discovered a novel heterozygous frameshift mutation (c.4379dup, p.Leu1461Thrfs*30) in exon 15 of the KMT2D gene. The diagnosis of our 4-year-old patient was made through thorough physical examination and history taking, and genetic testing. It is challenging to diagnose patients with Kabuki syndrome at birth, since the characteristic facial features are expressed gradually during growth. Clinical suspicion aroused by regular follow-ups may lead to earlier diagnosis and interventions.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.6
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• pp.565-571
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• 2009

Purpose: The aim of this study was to evaluate the clinical value of rectal gas distension F-18 FDG PET/CT imaging for the differentiation of the rectal focal uptake lesions. Materials and Methods: Twenty four patients (M:F=11:13, Age $62.8{\pm}12.4$ years) underwent rectal gas distension F-18 FDG PET/CT, prospectively: initial image at 50-60 min after the intravenous injection of F-18 FDG and rectal distension image after the infusion of air through the anus. Focally increased uptake lesions on initial images but disappeared on rectal distension images defined a physiological uptake. For the differential evaluation of persistent focal uptake lesions on rectal distension images, colonoscopy and histopathologic examination were performed. Results: Among the 24 patients, 27 lesions of focal rectal uptake were detected on initial images of F-18 FDG PET/CT. Of these, 7 lesions were able to judge with physiological uptake because the focal increased uptake disappeared from rectal distension image. Remaining 3 lesions were non-rectal lesions (2 lesions: rectovesical space, 1 lesion: uterine myoma). Among 17 lesions which was showed persistent increased uptake in rectal distension image, 15 lesions were confirmed as the malignant tumor (SUVmax=$15.9{\pm}6.8$) and 2 lesions were confirmed as the benign lesions including adenoma and inflammatory disease. Conclusion: The rectal distension F-18 FDG PET/CT imaging could be an important noninvasive method for the differentiation of malignant and benign focal rectal uptake lesions including physiologic uptake.