• Progress in Medical Physics
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• v.14 no.1
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• pp.34-42
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• 2003

In medical imaging, three-dimensional (3D) display using Virtual Reality Modeling Language (VRML) as a portable file format can give intuitive information more efficiently on the World Wide Web (WWW). The web-based 3D visualization of functional images combined with anatomical images has not studied much in systematic ways. The goal of this study was to achieve a simultaneous observation of 3D anatomic and functional models with planar images on the WWW, providing their locational information in 3D space with a measuring implement using VRML. MRI and ictal-interictal SPECT images were obtained from one epileptic patient. Subtraction ictal SPECT co-registered to MRI (SISCOM) was performed to improve identification of a seizure focus. SISCOM image volumes were held by thresholds above one standard deviation (1-SD) and two standard deviations (2-SD). SISCOM foci and boundaries of gray matter, white matter, and cerebrospinal fluid (CSF) in the MRI volume were segmented and rendered to VRML polygonal surfaces by marching cube algorithm. Line profiles of x and y-axis that represent real lengths on an image were acquired and their maximum lengths were the same as 211.67 mm. The real size vs. the rendered VRML surface size was approximately the ratio of 1 to 605.9. A VRML measuring tool was made and merged with previous VRML surfaces. User interface tools were embedded with Java Script routines to display MRI planar images as cross sections of 3D surface models and to set transparencies of 3D surface models. When transparencies of 3D surface models were properly controlled, a fused display of the brain geometry with 3D distributions of focal activated regions provided intuitively spatial correlations among three 3D surface models. The epileptic seizure focus was in the right temporal lobe of the brain. The real position of the seizure focus could be verified by the VRML measuring tool and the anatomy corresponding to the seizure focus could be confirmed by MRI planar images crossing 3D surface models. The VRML application developed in this study may have several advantages. Firstly, 3D fused display and control of anatomic and functional image were achieved on the m. Secondly, the vector analysis of a 3D surface model was defined by the VRML measuring tool based on the real size. Finally, the anatomy corresponding to the seizure focus was intuitively detected by correlations with MRI images. Our web based visualization of 3-D fusion image and its localization will be a help to online research and education in diagnostic radiology, therapeutic radiology, and surgery applications.

• Tuberculosis and Respiratory Diseases
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• v.66 no.6
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• pp.444-450
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• 2009

Background: Biomarkers for cancer have several potential clinical uses, including the following: early cancer detection, monitoring for recurrence prognostication, and risk stratification. However, no biomarker has been shown to have adequate sensitivity and specificity. Many investigators have tried to validate biomarkers for the early detection and recurrence of lung cancer. To evaluate plasma G-CSF as such a biomarker, protein levels were measured and were found to correlate with the clinicopathological features of primary lung tumors. Methods: Between December 2006 and May 2008, 100 patients with histologically-validated primary lung cancer were enrolled into this study. To serve as controls, 127 healthy volunteers were enrolled into this study. Plasma G-CSF levels were measured in lung cancer patients using the sandwich ELISA system (R & D inc.) prior to treatment. Results: The mean plasma G-CSF levels were 12.2$\pm$0.3 pg/mL and 46.0$\pm$3.8 pg/mL (mean$\pm$SE) in the normal and in the cancer groups, respectively. In addition, plasma G-CSF levels were higher in patients with early lung cancer than in healthy volunteers (p<.001). Plasma G-CSF levels were higher in patients who were under 65 years old or smokers. Within the cancer group, plasma G-CSF levels were higher in patients with non small cell lung cancer than in patients with small cell lung cancer (p<.05). Overall, plasma G-CSF levels were shown to increase dependent upon the type of lung cancer diagnsosed. In the order from highest to lowest, the levels of plasma G-CSF tended to decrease in the following order: large cell carcinoma, squamous cell carcinoma, adenocarcinoma, and bronchioloalveolar carcinoma. Plasma G-CSF levels tended to be higher in patients with advanced TNM stage than in localized TNM stage (I, II

• Progress in Medical Physics
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• v.18 no.2
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• pp.98-106
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• 2007

In June 2005, Yonsei University Medical Center, Severance Hospital upgraded a full-PACS system by adding twenty (5 mega pixels) Totoku ME511L flat panel LCD display devices for diagnostic interpretation purposes. Here we report upon the quantitative (or visual) acceptance testing of the twenty Totoku ME511L display devices for reflection, luminance response, luminance spatial dependency, resolution, noise, veiling glare, and display chromaticity based on AAPM TG 18 report. The tools used in the tests included a telescopic photometer, which was used as a colorimeter, illuminance meter, light sources for reflection assessment, light-blocking devices, and digital TG18 test patterns. For selected 8 flat panel displays, mean diffuse reflection coefficient ($R_d$) was $0.019{\pm}0.02sr^{-1}$. In the luminance response test, luminance ratio (LR), maximum luminance difference ($L_{max}$), and deviation of contrast response were $550{\pm}100,\;2.0{\pm}1.9%\;and\;5.8{\pm}1.8%$, respectively. In the luminance uniformity test, maximum luminance deviation was $14.3{\pm}5.5%$ for the 10% luminance of the TG18-UNL10 test pattern. In the resolution test with luminance measurement method, percent luminance (${\Dalta}L$) at the center was $0.94{\pm}0.64%$. In all cases of noise testing, rectangular target In every square in the three quadrants was visible and all 15 targets except the smallest one in the every corner pattern and the center pattern. The glare ratio (GR) was $12,346{\pm}1,995$. The color uniformity, (u',v'), was $0.0025{\pm}0.0008$. Also, the research results of qualify control guideline of primary disply devices suitable for domestic circumstance are presented All test results are in-line with the criteria recommended by AAPM TG18 report and are thus fully acceptable for diagnostic image interpretation. As a result, the acceptance testing schedule described provides not only an acceptance standard but also guidelines for quality control, optimized viewing conditions, and a means for determining the upgrading time of LCD display devices for diagnostic interpretation.

• Journal of the Korean Society of Radiology
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• v.14 no.2
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• pp.77-83
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• 2020

This study investigated the radiation protection of therapeutic radiologists. Based on the change in X-ray energy and MU value, the space dose rate in the treatment room after the irradiation was measured. 6MV, 10MV and 15MV photon beams were exposed to radiation inside the treatment room based on 300MU, 600MU and 1000MU using a linear accelerator. And repeated 10 times under the same conditions. As a result of the experiment, 0.1555 μSv/h for 6MV 300MU, 0.157 μSv /h for 300sec, 0.152 μSv/h, 0.156 μSv/h for 600MU, and 0.157 μSv/h 0.152 μSv/h for 1000MU. 300MU of 10MV was 0.49 μSv/h, 0.309 μSv/h, and 0.69 μSv/h, 0.416 μSv/h for 600MU, respectively, and 1000MU was 0.977 μSv/h and 0.478 μSv/h, respectively. The 300MU of 15MV was 3.02 μSv/h, 1.2 μSv/h, 5.459 μSv/h at 600MU, 7.34 μSv/h at 1.836 μSv/h 1000MU, and 2.709 μSv/h. The average spatial dose rate of 6MV was not significantly different from the natural spatial dose rate in the treatment room. High spatial dose rates were measured at 10 MV and 15 MV and were attenuated over time. Therefore, entering the treatment room after a certain period of time (more than 60 seconds) is considered to be effective to prevent the exposure dose of radiation workers.

• Tuberculosis and Respiratory Diseases
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• v.64 no.5
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• pp.362-368
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• 2008

Background: LKB1(STK11) is a serine/threonine kinase that functions as a tumor growth suppressor. The functions of LKB1 in lung cancer are not completely understood. This study evaluated the relationship between LKB1 protein expression and the clinicopathological features in lung cancer tissues. Methods: The expression of LKB1 was studied in paraffin-embedded tumor blocks, which were obtained from 77 patients who had undergone surgery at Wonkwang University Hospital. The expression of the LKB1 protein was considered positive if the staining intensity in the tumor tissue adjacent to the normal airway epithelium was >30%. Results: The LKB1 expression was positive in 31 (40%) of samples. Loss of LKB1 expression was significantly associated with being male, smoking history, and squamous cell carcinoma. In the peripheral sites, the loss of LKB1 expression was strongly associated with a smoking history. A loss of LKB1 expression was more frequently associated with progression according to TNM staging, particularly more than T2, N progression. Conclusion: There was a significant relationship between the loss of the LKB1 protein and gender, smoking history, and histological type in primary lung cancer. Although LKB1 expression was not found to be a significant prognostic factor, further studies with a larger cohort of patient's lung cancer tissue samples will be needed to confirm this.

• Journal of Gastric Cancer
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• v.6 no.4
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• pp.237-243
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• 2006

Purpose: This study was conducted to evaluate the treatment outcomes and the prognosis for gastric cancer patients with hepatic metastasis. Materials and Methods: This retrospective study was based on the medical records of 85 gastric cancer patients with hepatic metastasis (62 synchronous and, 23 metachronous) who received chemotherapy with or without resectional therapy from March 1990 to March 2006. The survival rate was analyzed according to clinicopathologic factors and therapeutic factors, such as whether or not a gastrectomy, a hepatic resection, and/or chemotherapy had been performed. Results: The median survival of gastric cancer patients with hepatic metastasis was 11 months (synchronous: 11 months and metachronous: 17 months). The rates of gastrectomies and hepatic resections in the synchronous group were 24.1% and 16.1%, respectively A 23.5% prevalence of extra-hepatic metastasis was observed. The median survivals of patients who underwent a gastrectomy with a hepatic resection, a gastrectomy alone, and non-surgical treatment were 60, 18, and 9 months, respectively (P<0.05). The disease-free median survival of the metachronous group was 8 ($3{\sim}39$) months. There was no difference in initial pathologic stage and frequency of hepatic metastasis after the gastrectomy in the metachronous group. In the synchronous group, extra-hepatic metastasis, a gastrectomy as the operative procedure, a hepatic resection as the operative procedure and the response to chemotherapy were statistically significant in the univariate analysis, and a hepatic resection as the operative procedure, the response to chemotherapy, and extra-hepatic metastasis were independant prognostic factors identified by the multivariate analysis. In the metachronous group, extra-hepatic metastasis, the response to chemotherapy and differentiation were statistically significant in the univariate analysis, and extra-hepatic metastasis was an independent prognostic factor identified by the multivariate analysis. Conclusion: An aggressive surgical therapy and effective chemotherapy are necessary in the treatment of gastric cancer patients with hepatic metastasis. (J Korean Gastric Cancer Assoc 2006;6:237-243)

• Nuclear Medicine and Molecular Imaging
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• v.42 no.3
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• pp.201-208
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• 2008

Purpose: We aimed to assess the role of positron emission tomography using fluorodeoxyglucose (FDG-PET) in the diagnosis of recurrence or the assessment of therapeutic response in cervical and ovarian cancer patients through making a comparison between FDG-PET, abdominal computed tomography (CT) and serum tumor marker. Materials and methods: We included 103 cases (67 patients) performed FDG-PET and abdominal CT. There were 42 cervical cancers and 61 ovarian cancers. We retrospectively reviewed the interpretations of PET and CT images as well as the level of tumor marker. We calculated their sensitivity, specificity, positive predictive value and negative predictive value for these three modalities. And then we analyzed the differences between these three modalities. Results: Tumor recurrences were diagnosed in 37 cases (11 cervical cancers and 26 ovarian cancers). For PET, CT and tumor marker, in cervical cancer group, sensitivity was 100% (11/11), 54.5% (6/11) and 81.1% (9/11), respectively. And specificity was 93.6% (29/31), 93.6% (29/31) and 100% (31/31). In ovarian cancer group, sensitivity was 96.2% (25/26), 84.6% (22/26) and 80.8% (21/26), and specificity was 94.3% (33/35), 94.3% (33/35), 94.3% (33/35), PET was highly sensitive to detect the intraperitoneal and extraperitoneal metastasis with the help of the CT images to localize the lesions. However, CT had limitations in differentiation of the recurrent tumor from benign fibrotic tissue, identification of viable tumors at the interface of tissues, and detecting extraperitoneal lesions. Conclusion: FDG-PET can be an essential modality to detect the recurrent or residual tumors in gynecologic cancer patients because of its great field of the application and high sensitivity.

• Korean Journal of Psychosomatic Medicine
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• v.10 no.2
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• pp.92-100
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• 2002

Objectives : As medical science develops, survival rate of cancer patients rises. Therefore, psychologic understanding and improving quality of life in cancer patients is getting greater significance. The Object of this study is to investigate sociodemographic and clinical characteristics, psychopathology, self esteem and quality of life in cancer patients and to provide useful information for therapeutic approach to cancer patients. Methods : The subjects were 41 patents who had been treated by radiotherapy and 20 normal people. Sociodemographic information and clinical characteristics of cancer patients were investigated, and SCL-90R for psychopathology, Rosenberg Self-esteem Scale for self esteem, WHOQOL-BREF for quality of life were administered to subjects. The results of both groups were compared and analysed, and correlation between variables were evaluated. Results : 1) The tendency of Somatization, obsession-compulsion, depression, anxiety, hostility, phobia, psychosis in cancer group were higher than normal group. Especially, somatization and anxiety in cancer group were significantly higher than normal group. 2) Self esteem and quality of life in cancer group were significantly lower than normal group. 3) No significance were found in comparison of psychopathology, self esteem and quality of life according to sociodemographic variables. Among clinical characteristics, higher somatization was shown in case of more weight loss, and higher somatization and lower quality of life was shown in the presence of pain. 4) Higher anxiety was significantly associated with lower self esteem, and Higher somatization and anxiety was significantly associated with lower quality of life. Conclusion : Cancer patients had various kinds of psychopathology, low self esteem and low quality of life. In particular, somatization and anxiety, self esteem and pain were found to be important factors to quality of life of cancer patients. Therefore, management of psychopathology, improving self esteem, pain control is necessary to improve quality of life in cancer patients.

• Journal of Yeungnam Medical Science
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• v.17 no.2
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• pp.137-145
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• 2000

Background: Hepatocellular carcinomal(HCC) has been considered to be relatively radioresistant. The role of radiotherapy(RT) in the treatment of HCC is controversial. But RT has a role in the treatment of hepatocellular carcinoma as a single or combination modalities. The effect of radiotherapy on HCC was evaluated. Patients and Methods: From January 1984 through January 2000, a total of 18 patients with unresectable HCC underwent radiotherapy alone or in conjunction with transarterial embolization(TAE). We reviewed the medical ecords of patients treated with RT and measured the tumor size using measured the tumor size using planimetry method. The Kaplan-Meier method was used to calculate the survival rate. Results: The RT patients were 15 men and 3 women. The mean age was 51 years. four(22.2%) of them were accompanied with ascites. Eleven(61.1%) of them were accompanied with liver cirrhosis and their functions were 6, 3, 2 in each Child-Pugh A, B, C, respectively. A partial response(PR) was observed in 2 patients(11.1%), minimal response(MR) in 4 patients (22.2%) and no change(NC), in 11 patients(61.1%), whereas progressive disease(PD) was seen in 1 patients(6%), respectively. Conclusions: Although the radiotherapy in HCC did not improve the survival rate. it decreased the tmor size. Radiotherapy strengthens the therapeutic efficacy when combined with TAE, but more studies are needed.

• Radiation Oncology Journal
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• v.22 no.1
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• pp.55-63
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• 2004

Purpose : To evaluate the reflection of tumor motion according to the planning CT scan time. Material and Methods : A model of N-shape, which moved aiong the longitudinal axis during the ventilation caused by a mechanical ventilator, was produced. The model was scanned by planning CT, while setting the relative CT scan time (T: CT scan time/ventilatory period) to 0.33, 0.50, 0.67, 0.75, 1.00, 1.337, and 1.537. In addition, three patients with non-small cell lung cancer who received stereotactic radiosurgery In the Department of Radiation Oncology, Asan Medical Center from 03/19/2002 to 05/21/2002 were scanned. Slow (10 Premier, Picker, scan time 2.0 seconds per slice) and fast CT scans (Lightspeed, GE Medical Systems, with a scan time of 0.8 second per slice) were peformed for each patient. The magnitude of reflected movement of the N-shaped model was evaluated by measuring the transverse length, which reflected the movement of the declined bar of the model at each slice. For patients' scans, all CT data sets were registered using a stereotactic body frame scale with the gross tumor volumes delineated in one CT image set. The volume and three-dimensional diameter of the gross tumor volume were measured and analyzed between the slow and fast CT scans. Results : The reflection degree of longitudinal movement of the model increased in proportion to the relative CT scan times below 1.00 7, but remained constant above 1.00 T Assuming the mean value of scanned transverse lengths with CT scan time 1.00 T to be $100\%$, CT scans with scan times of 0.33, 0.50, 0.57, and 0.75 T missed the tumor motion by 30, 27, 20, and $7.0\%$ respectively, Slow (scan time 2.0 sec) and Fast (scan time 0.8 sec) CT scans of three patients with longitudinal movement of 3, 5, and 10 mm measured by fluoroscopy revealed the increases in the diameter along the longitudinal axis Increased by 6.3, 17, and $23\%$ in the slow CT scans. Conculsion : As the relative CT scan time increased, the reflection of the respiratory tumor movement on planning CT also Increased, but remained constant with relative CT scan times above 1.00 T When setting the planning CT scan time above one respiration period (>1.00 T), only the set-up margin is needed to delineate the planning target volume. Therefore, therapeutic ratio can be increased by reducing the radiation dose delivered to normal lung tissue.