• Journal of radiological science and technology
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• v.39 no.3
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• pp.377-384
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• 2016

This is a study on the optimized dispensing of the auto dispenser used for the purpose of reducing the exposure dose and accurate radiation dose of radioisotope with regard to the PET/CT practitioners. The research method was to find the optimized dispensing method through evaluating the results according to the syringe type, dispensing rate, and vial pressure and through the application of corrected values. As a result of this study, 9.38 mCi has been dispensed on average in the case of 5 ml syringe, and the reproducibility close to 10 mCi was shown at the dispense of 9.55 mCi in the case of 3 ml syringe. In the evaluation according to the dispensing rate, the quantity of radioisotope close to 10 mCi was dispensed at the rate of 5 mm/min when the measurement was carried out by increasing the rate by 5 mm/min units in the order of 5, 10, 15 and 20 mm/min. In the evaluation result according to the vial pressure before/after the use of Needle filter, it was measured to be 9.53 mCi before use and 9.84 mCi after use confirming that the dispensing after using Needle filter showed the optimal value. In addition, in the evaluation of radioactivity before/after the application of corrected values according to the increase in dispense frequency, it was measured 9.53 mCi before correction and 10.07 mCi after correction confirming that the value with correction applied was closer to the quantitative value. Thus, a good optimized method was confirmed to use a 3 ml syringe with dispensing rate of 5 mm/min, to use a Needle filter at dispensing, and to set the corrected value of [$y=0.097{\times}x$] according to the dispensing frequency of equipment.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.51-56
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• 2009

Purpose: Recently, most hospitals are introducing the PACS system and use of the system continues to expand. But small-scaled PACS called MicroPACS has already been in use through open source programs. The aim of this study is to prove utility of operating a MicroPACS, as a substitute back-up device for conventional storage media like CDs and DVDs, in addition to the full-PACS already in use. This study contains the way of setting up a MicroPACS with open source programs and assessment of its storage capability, stability, compatibility and performance of operations such as "retrieve", "query". Materials and Methods: 1. To start with, we searched open source software to correspond with the following standards to establish MicroPACS, (1) It must be available in Windows Operating System. (2) It must be free ware. (3) It must be compatible with PET/CT scanner. (4) It must be easy to use. (5) It must not be limited of storage capacity. (6) It must have DICOM supporting. 2. (1) To evaluate availability of data storage, we compared the time spent to back up data in the open source software with the optical discs (CDs and DVD-RAMs), and we also compared the time needed to retrieve data with the system and with optical discs respectively. (2) To estimate work efficiency, we measured the time spent to find data in CDs, DVD-RAMs and MicroPACS. 7 technologists participated in this study. 3. In order to evaluate stability of the software, we examined whether there is a data loss during the system is maintained for a year. Comparison object; How many errors occurred in randomly selected data of 500 CDs. Result: 1. We chose the Conquest DICOM Server among 11 open source software used MySQL as a database management system. 2. (1) Comparison of back up and retrieval time (min) showed the result of the following: DVD-RAM (5.13,2.26)/Conquest DICOM Server (1.49,1.19) by GE DSTE (p<0.001), CD (6.12,3.61)/Conquest (0.82,2.23) by GE DLS (p<0.001), CD (5.88,3.25)/Conquest (1.05,2.06) by SIEMENS. (2) The wasted time (sec) to find some data is as follows: CD ($156{\pm}46$), DVD-RAM ($115{\pm}21$) and Conquest DICOM Server ($13{\pm}6$). 3. There was no data loss (0%) for a year and it was stored 12741 PET/CT studies in 1.81 TB memory. In case of CDs, On the other hand, 14 errors among 500 CDs (2.8%) is generated. Conclusions: We found that MicroPACS could be set up with the open source software and its performance was excellent. The system built with open source proved more efficient and more robust than back-up process using CDs or DVD-RAMs. We believe that the operation of the MicroPACS would be effective data storage device as long as its operators develop and systematize it.

• Tuberculosis and Respiratory Diseases
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• v.47 no.5
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• pp.642-649
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• 1999

Background: It is very important to determine an accurate staging of the non-small cell lung cancer(NSCLC) for an assessment of operability and it's prognosis. However, it is difficult to evaluate tumor involvement of mediastinal lymph nodes accurately utilizing noninvasive imaging modalities. PET is one of the sensitive and specific imaging modality. Unfortunately PET is limited use because of prohibitive cost involved with it's operation. Recently hybrid SPECT/PET(single photon emission computed tomography/positron emission tomography) camera based PET imaging was introduced with relatively low cost. We evaluated the usefulness of coincidence detection(CoDe) PET in the detection of metastasis to the mediastinal lymph nodes in patients with NSCLC. Methods: Twenty one patients with NSCLC were evaluated by CT or MRI and they were considered operable. CoDe PET was performed in all 21 patients prior to surgery. Tomographic slices of axial, coronal and sagittal planes were visually analysed. At surgery, mediastinal lymph nodes were removed and histological diagnosis was performed. CoDe PET findings were correlated with histological findings. Results: Twenty of 21 primary tumor masses were detected by the CoDe PET. Thirteen of 21 patients was correctly diagnosed mediastinal lymph node metastasis by the CoDe PET. Pathological N0 was 14 cases and the specificity of N0 of CoDe PET was 64.3%. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of N1 node was 83.3%, 73.3%, 55.6%, 91.7%, and 76.2% respectively. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of N2 node was 60.0%, 87.5%, 60.0%,87.5%, and 90.0% respectively. There were 3 false negative cases but the size of the 3 nodes were less than 1cm. The size of true positive nodes were 1.1cm, 1.0cm, 0.5cm respectively. There were 1 false positive among the 12 lymph nodes which were larger than 1cm. False positive cases consisted of 1 tuberculosis case, 1 pneumoconiosis case and 1 anthracosis case. Conclusion: CoDe PET has relatively high negative predictive value in the enlarged lymph node in staging of mediastinal nodes in patients with NSCLC. Therefore CoDe PET is useful in ruling out metastasis of enlarged N3 nodes. However, further study is needed including more number of patients in the future.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2004.11a
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• pp.91-95
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• 2004

Several MRI studies have reported reductions in temporal lobe volumes in Alzheimer's disease (AD). Measures have been usually obtained with regions-of-interest (ROI) drawn manually on selected medial and lateral portions of the temporal lobes, with variable choices of anatomical borders across different studies. We used the automated voxel-based morphometry (VBM) approach to investigate gray matter abnormalities over the entire extension of the temporal lobe in 10AD patients (MM5E 22)and 22 healthy controls. Foci of significantly reduced gray matter volume in AD patients were detected in both medial and lateral temporal regions, most significantly in the right and left posterior parahippocarmpal gyri. At a more flexible statistical threshold (P<0.01, uncorrected for multiple comparisons), circumscribed foci of significant gray matter reduction were also detected in the right amygdala/enthorinal cortex, the anterior and posterior borders of the superior temporal gyrus bilaterally, and the anterior portion of the left middle temporal gyrus. These VBM results confirm previous findings of temporal lobe atrophic changes in AD, and suggest that these abnormalities may be confined to specific sites within that lobe, rather than showing a widespread distribution.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.22-27
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• 2014

Purpose There is the recent PET/CT scan in tendency that use low dose to reduce patient's exposure along with development of equipments. We diminished $^{18}F$-FDG dose of patient to reduce patient's exposure after setting up GE Discovery 690 PET/CT scanner (GE Healthcare, Milwaukee, USA) establishment at this hospital in 2011. Accordingly, We evaluate acquisition time per proper bed by change of infusion dose to maintain quality of image of PET/CT scanner. Materials and Methods We inserted Air, Teflon, hot cylinder in NEMA NU2-1994 phantom and maintained radioactivity concentration based on the ratio 4:1 of hot cylinder and back ground activity and increased hot cylinder's concentration to 3, 4.3, 5.5, 6.7 MBq/kg, after acquisition image as increase acquisition time per bed to 30 seconds, 1 minute, 1 minute 30 seconds, 2 minute, 2 minutes 30 seconds, 3 minutes, 3 minutes 30 seconds, 4 minutes, 4 minutes 30 seconds, 5 minutes, 5 minutes 30 seconds, 10 minutes, 20 minutes, and 30 minutes, ROI was set up on hot cylinder and back radioactivity region. We computated standard deviation of Signal to Noise Ratio (SNR) and BKG (Background), compared with hot cylinder's concentration and change by acquisition time per bed, after measured Standard Uptake Value maximum ($SUV_{max}$). Also, we compared each standard deviation of $SUV_{max}$, SNR, BKG following in change of inspection waiting time (15minutes and 1 hour) by using 4.3 MBq phantom. Results The radioactive concentration per unit mass was increased to 3, 4.3, 5.5, 6.7 MBqs. And when we increased time/bed of each concentration from 1 minute 30 seconds to 30 minutes, we found that the $SUV_{max}$ of hot cylinder acquisition time per bed changed seriously according to each radioactive concentration in up to 18.3 to at least 7.3 from 30 seconds to 2 minutes. On the other side, that displayed changelessly at least 5.6 in up to 8 from 2 minutes 30 seconds to 30 minutes. SNR by radioactive change per unit mass was fixed to up to 0.49 in at least 0.41 in 3 MBqs and accroding as acquisition time per bed increased, rose to up to 0.59, 0.54 in each at least 0.23, 0.39 in 4.3 MBqs and in 5.5 MBqs. It was high to up to 0.59 from 30 seconds in radioactivity concentration 6.7 MBqs, but kept fixed from 0.43 to 0.53. Standard deviation of BKG (Background) was low from 0.38 to 0.06 in 3 MBqs and from 2 minutes 30 seconds after, low from 0.38 to 0 in 4.3 MBqs and 5.5 MBqs from 1 minute 30 seconds after, low from 0.33 to 0.05 in 6.7 MBqs at all section from 30 seconds to 30 minutes. In result that was changed the inspection waiting time to 15 minutes and 1 hour by 4.3 MBq phantoms, $SUV_{max}$ represented each other fixed values from 2 minutes 30 seconds of acquisition time per bed and SNR shown similar values from 1 minute 30 seconds. Conclusion As shown in the above, when we increased radioactive concentration per unit mass by 3, 4.3, 5.5, 6.7 MBqs, the values of $SUV_{max}$ and SNR was kept changelessly each other more than 2 minutes 30 seconds of acquisition time per bed. In the same way, in the change of inspection waiting time (15 minutes and 1 hour), we could find that the values of $SUV_{max}$ and SNR was kept changelessly each other more than 2 minutes 30 seconds of acquisition time per bed. In the result of this NEMA NU2-1994 phantom experiment, we found that the minimum acquisition time per bed was 2 minutes 30 seconds for evaluating values of fixed $SUV_{max}$ and SNR even in change of inserting radioactive concentration. However, this acquisition time can be different according to features and qualities of equipment.

• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.139-145
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• 2010

Cystic parathyroid adenoma is one of rare causes of hyperparathyroidism, and tends to cause increased serum level of parathyroid hormone, alkaline phosphate and serum calcium level similar to when compared to those of solid adenoma. The possibility of a coincidental appearance of primary hyperparathyrodism and nonmedullary thyroid cancer is rare, and often neglected. A 40-year-old female presented with constipation and weight loss for 3 months. The serum calcium, phosphate and alkaline phosphate were 16.6 mg/dl, 2.2 mg/dl and 505 IU/L respectively and serum parathyroid hormone level was 1556.2 pg/mL. Neck US showed mixed nodules at both thyroid lobes, and PET-CT showed a right thyroid nodule without FDG uptake. The patient was diagnosed of primary hyperparathyroidism and underwent parathyroidectomy and a total thyroidectomy. Histopathologic results revealed parathyroid adenoma with cystic change (2 cm greater diameter) in the right lower parathyroid gland and coexistent papillary carcinoma of the right lobe of thyroid gland (infiltrating, 0.3 cm in greater diameter). She remained well and serum calcium, phosphate, parathyroid hormone level were normalized within 24 hours.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.1
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• pp.18-24
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• 2017

Patient-specific image-based internal dosimetry involves using the patient's individual anatomy and spatial distribution of radioactivity over time to obtain an absorbed dose calculation. Individual absorbed dose was calculated by accumulated activity multiply S-value of each organs. The aim of this study was to calculate the S-values using Monte Carlo simulation in monkey and mouse and evaluation of absorbed dose in each organ. Self-irradiation S-value of monkey heart self-irradiation was 3.15E-03 mGy-g/MBq-s, lung self-irradiation was 8.94E-04 mGy-g/MBq-s and liver self-irradiation S-value was 2.23E-03 mGy-g/MBq-s. Mouse heart self-irradiation S-value was 1.95E-01 mGy-g/MBq-s, lung was 9.59E-02 mGy-g/MBq-s, and liver was 1.40E-03 mGy-g/MBq-s. The results of this study show that the calculation protocol of image based individual absorbed dose of each organ using Monte Carlo simulation. Therefore, this study may be applied to calculate human specific absorbed dose.

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.50-53
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• 2007

Adrenal metastasis from papillary thyroid carcinoma is extremely rare. We present herein a patient with adrenal metastases from recurrent papillary carcinoma of the thyroid. A 54 year-old woman had received a total thyroidectomy and postoperative radioactive iodine therapy for locally advanced papillary thyroid carcinoma. One year after initial surgery, distant metastases to multiple organs including right cervical lymph nodes, left upper lung, left 2nd and 3rd ribs, 2nd thoracic vertebra and left adrenal gland were found by 18-FDG-PET-CT whole body scan. She underwent right modified neck dissection, partial resection of left 2nd and 3rd ribs, posterior arch of 2nd thoracic vertebra, left upper lobectomy of lung, and left adrenalectomy. On histologic examination, metastases to the left adrenal gland and cervical lymph nodes were papillary thyroid carcinomas, while other metastatic sites turned out to be anaplastic thyroid carcinomas. Despite aggressive surgery and postoperative adjuvant therapy, her general clinical conditions were getting worse day by day due to regrowing of the anaplastic thyroid carcinomas. To our knowledge, this is the first case reported in Korea.

• Archives of Plastic Surgery
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• v.37 no.3
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• pp.277-280
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• 2010

Purpose: The resection of locally advanced or recurred breast cancers frequently result in large chest wall defects and it leads to a great challenges to cover. Generally simple skin grafts are not a practical option for patients because of their poor cosmetic appearance and prognosis. The latissimus dorsi and rectus abdominis musculocutaneous flap have traditionally been recommended for closure of these large defects. Though the cosmetic result of reconstruction using these flaps is often excellent, but has significant drawbacks. Therefore, we thought that chest wall reconstruction using the external oblique musculocutaneous flap can be an alternative method for extensive chest wall defect related to large, locally advanced breast carcinoma. Methods & Results: We present a case of a 50-year-old Korean female, refered to our department with a left breast tumor for 10 months. CT demonstrate a large tumor on the left anterior chest wall and multiple nodules of varying size in the cervical areas and liver. FDG-PET showed areas of hot uptake throughout the left chest wall, mediastinum and liver. Biopsy was consistent with invasive ductal carcinoma (Grade III). The initial tumor was considered inoperable, so a series of chemotherapy was initiated. Though the size of the breast mass was slightly decreased, the patient continued to suffer from purulent discharge, unpleasant odor and contact bleeding of the mass, the salvage mastectomy was performed. Conclusion: We could reconstruct $23{\times}16\;cm$ sized large chest wall defect, resulting from the resection of a locally advanced breast carcinoma, using an external oblique musculocutaneous flap successfully. Immediate postoperatively checked flap was healthy. Overall result was good without any significant complications and discharged 3 weeks after operation.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.607-610
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• 2008

Purpose: Salivary duct carcinoma(SDC) is uncommon but high grade adenocarcinoma arising in the ductal epithelium of salivary glands. SDC is characterized by distinctive clinical and pathologic features. The most important histologic aspect of this neoplasm is its resemblance to ductal carcinoma of the breast. Clinically SDC is defined by cervical lymph node involvement and distant metastasis with a high rate of recurrence and mortality. We described some of the clinical and pathological features of SDC and the management using case report for our patient. Methods: We present a case of a 40-year-old male with 2-year history of a swelling arising in his left preauricular region. There was a single painless, firm and solid $2{\times}1.5cm$ mass in the left parotid area. Facial nerve function was intact and no cervical lymph node were palpable. In August 2005, we found out $1.7{\times}1.8cm$ sized cystic, nodular lesions that were located in the superficial lobe of left parotid gland through Computed tomography. And then superficial parotidectomy and postoperative radiation therapy were performed in Jan 2007. Results: Pathologically, the specimen were consisted of homogeneous, chondoid to myxoid type of tissues. It was yellow mass that has multiloculated cystic lesions. In postoperative PET(Positiron emission tomography) CT, there was no evidence of uptaking FDG(Fluorodeoxyglucose) into the deep layers of parotid gland and distant metastasis were not seen. Conclusion: Salivary duct carcinoma(SDC) is a rare but high grade adenocarcinoma related to pleomorphic adenocarcinoma. The prognosis of SDC can be different according to the type of tumor such as mucoepidermoid adenocarcinoma, adenoid duct carcinoma and acinar cell carcinoma. So we need to study more carefully for accurate diagnosis in early stage of diagnosis. Although radiotherapy has not yet proven to be a significant factor in overall survival, the combination of parotidectomy and postoperative radiation therapy can lead to more favorable results in treating of SDC.