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The Usefulness of Q.Clear Technique in PET / CT (PET/CT 검사에서 Q.Clear 기법의 유용성에 대한 고찰)

  • Choi, Yong Hoon;Kim, Jung Yul;Choi, Young Sook;Lim, Han Sang;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.2
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    • pp.31-36
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    • 2017
  • Purpose Recently, the performance of PET/CT scanner has been improved and various techniques have been developed to increase the image quality such as Sensitivity and Resolution. The purpose of this study is to evaluate the usefulness of Q.Clear (a fully convergent iterative reconstruction) technique of GE Discovery IQ equipment to enhance the image quality. Materials and Methods All scans were acquired by Discovery IQ (GE Healthcare, MI, USA). In NEMA IEC Body Phantom test, Background to Hot-sphere (10 mm, 13 mm, 17 mm, 22 mm) ratio was 1:4 and scan time was 3 minutes. The images were reconstructed by VPHDs (VUE Point High-Definition + SharpIR) and Q.Clear to evaluate each Contrast. We injected 18F-FDG 187 M㏃ to PET/SPECT Performance Phantom. And then it was scanned for 4 minutes to evaluate Resolution and Uniformity. T-test statistical analysis was performed on SUVmax of small lesions less than 2 cm in 100 clinical patients regardless of disease type. Results In the NEMA IEC Body Phantom, the Contrast was $63.6{\pm}5.7%$ (VPHDs) and $75{\pm}4.8%$ (Q.Clear). In the PET/SPECT Performance Phantom, the Resolution was 9.2 mm (VPHDs) and 7.3 mm (Q.Clear). Uniformity of Q.Clear was 10.8% better than VPHDs. T-test statistic of the clinical patients showed a significant difference of p value of 0.021. Conclusion Both the phantom test and the clinical results showed that the quality of the image was improved in Q.Clear was applied. The SUVmax was highly measured in Q.Clear and the lesions were clearly distinguished visually. Therefore Q.Clear can be useful in various aspects such as dose-reduction, patients evaluation and image analysis.

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A Role of Trial Radiation Therapy in the Pineal Region Tumors (송과체부 종양에서 시험적 방사선치료의 역할)

  • Kim, Yeon-Shil;Ryu, Mi-Ryung;Chung, Su-Mi;Kim, Moon-Chan;Yoon, Sei-Chul
    • Radiation Oncology Journal
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    • v.20 no.2
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    • pp.100-107
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    • 2002
  • Purpose : The aim of this retrospective study was to assess the treatment results of 30 patients with pineal region tumors who were underwent radiation therapy under the diagnosis by either CT or MRI. There was no histological verification. We analyzed the prognostic factors that have a significant effect on the overall survival (OS) and disease free survival (DFS) rates. Materials and Methods : A total 30 patients with pineal region tumors were treated between March 1983 and August 1995. After a trial radiation therapy of $20\~30\;Gy/2\~3$ weeks, the patients were evaluated for their clinical response and radiological response by either CT or MRI and the final treatment direction was then decided. According to their response to the trial radiation therapy and the involved site, radiation treatment was given in various fields i.e., local, ventricle, whole brain and craniospinal field. The radiation dose ranged from 40.8 to 59.4 Gy (Median 50.4 Gy). The median follow up was 36.5 months $(4\~172\;months)$. Results : An improvement or stability in the clinical symptoms was observed in 28 patients $(93.3\%)$ after the trial RT. Nineteen patients $(63.3\%)$ showed a partial or complete response by CT or MRI. The two-year and five-year survival rates of the patients were $66.7\%$ and $55.1\%$, respectively. No significant difference in the survival rates according to the degree of the radiological response was abserved after the trial RT. The results of univariate analysis showed that age, the primary site, the performance status $(KPS\geq70)$, the degree of response after completing RT and the RT field were significant prognostic factors affecting the survival and disease free survival rates (p<0.05). Conclusion : The clinical and histological characteristics of pineal region tumors are quite complex and diverse. Therefore, it is difficult to predict the histological diagnosis and the possibility of radiocurability only with the initial response to RT. We think that the development of less invasive histological diagnostic techniques and tailored treatment to the histological type of each tumor are needed.

Effects of Postoperative Radiation Therapy for Prevention of Keloids and Hypertrophic Scars (켈로이드와 비후성 반혼에서 재발을 방지하기 위한 수술후 방사선치료의 효과)

  • Kang, Ki-Mun;Choi, Ihl-Bohng;Kim, In-Ah;Jang, Jee-Young;Shinn, Kyung-Sub
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.269-276
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    • 1997
  • Purpose : To evaluate the effects of surgical excision followed by radiation therapy for Prevention of keloids and hypertrophic scars. Materials and Methods : From October 1987 to April 1995, radiation therapy was applied to 167 sites in 106 patients with surgical excision in an attempt to prevention of recurrence against keloids and hypertrophic scars. The main etiology of the keloids and hypertrophic scars were surgery in $49.2\%,\;trauma\;in\;25.0\%,\;ear-piercing\;in\;5.4\%,\;and\;burn\;in\;5.4\%$, The Patients' ages ranged from 3 to 70 years with a median of 32 years. Radiation therapy used ranged from 6 to 8MeV electron beam. Radiation therapy was delivered within 24 hours of surgical excision. Several dose schedules were used, varing from 400cGy in 1 daily fraction to 1900cGy in 4 daily fractions. The average total dose was 1059cGy, and the average dose per fraction was 433cGy. All patients were followed up from 24 to 114 months with a median follow up of 49 months. Results : The overall recurrence rate was $12.6\%$ (21/167) The overall 1-year and 2-year recurrence rates were $10.2\%\;and\;11.4\%$, respectively Among 21 recurrent sites, seventeen sites $(81\%)$ were confirmed within 12 months after surgical excision. Period to recurrence ranged from 1 month to 47 months with a median recurrence time of 9.6 months, The history of previous therapy was only a significant factor in recurrence. Twenty-four patients had history of previous therapy recurrence rates was significantly higher in this group than those without history of Previous therapy $(22.6\%\;vs.\;11.0\%,\;p=0.04)$. There was no serious complication related to radiation therapy. Conclusion : This study suggests that surgical excision followed by radiation therapy is an effective method of preventing keloids and hypertrophic scars.

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The Effects of Neck Irradiation on Thyroid Gland for Tumors of the Head and Neck -A prospective analysis of 75 cases- (두경부종양 환자에서 경부 방사선조사가 갑상선기능에 미치는 영향 -75예의 전향적 분석-)

  • Park In Kyu;Kim Sang Bo;Yun Sang Mo;Park Jun Sik;Jun Su Han;Kim Bo Wan
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.59-66
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    • 1994
  • Seventy-five patients with tumors of the head and neck treated with either radiation therapy alone or combined with surgery or chemotherapy were studied prospectively to evaluate the effects of radiation therapy to the neck on thyroid gland between September 1986 and October 1992. All patients were serially monitored for thyroid function tests before and after radiation therapy. Radiation dose to the thyroid gland ranged from 35 to 60 Gy with a median dose of 50 Gy. Median follow-up time was 30 months with a range of 11 to 85 months. The incidence of thyroid dysfunction was 40$ \% $: forty-five patients(60$ \% $) euthyroid, 2 patients(3$ \% $) clinical hypothyroidism, 27 patients(36$ \% $) subclinical hypothyroidism and 1 patient(1$ \% $) hyperthyroidism. No thyroid nodules or thyroid cancer were detected in any patients. Thyroid dysfunction appeared earlier in patients who underwent surgery than in those patients treated with radiation therapy alone or combination of chemotherapy and radiation therapy(P=0.0013). By multivariate analysis, risk factors that significantly influenced a higher incidence of thyroid dysfunction were female sex(p=0.0293) and combination of total laryngectomy and radiation therapy(p : 0.0045). In conclusion, evaluation of thyroid function before and after radiation therapy with periodic thyroid function tests are recommended to detect thyroid dysfunction in time and thyroid hormone replacement therapy is recommended whenever thyroid dysfunction develops.

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Usefulness of wearing pocket dosimeter in nuclear medicine (핵의학 영상검사에서 Pocket dosimeter 착용의 유용성 평가)

  • Kim, Young-Bin;Lee, Eun-Ji;Kim, Kun-Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.25-28
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    • 2011
  • Purpose: The aim of study is to find accuracy of pocket dosimeter in measuring exposed dose in compared with survey meter and to compare exposed dose according as Nuclear medicine exams. Materials and Method: First, radiation dose to point source(185 MBq,370 MBq, ${\ldots}$, 1665 MBq, 1850 MBq) were measured in using a pocket dosimeter and a survey meter. Second, radiation dose to 12 patients injected $^{18}F$-FDG 370 MBq were measured in using a pocket dosimeter and a survey meter. Third, radiation dose to 10 patients injected $^{99m}Tc$-DPD 925 MBq were measured in using a pocket dosimeter and a surveymeter. Result: The average is $70.12{\pm}39.36{\mu}Sv/h$ in measurement of point source with Surveymeter and $5{\pm}3.06{\mu}Sv$ in measurement of point source with Pocket dosimeter. The average is $25.04{\pm}6.16{\mu}Sv/h$ in measurement of PET/CT patients with Surveymeter and $2.41{\pm}0.51{\mu}Sv$ in measurement of PET/CT with Pocket dosimeter. The average is $8.58{\pm}0.96{\mu}Sv/h$ in measurement of Bone Scan patients with Surveymeter and $1{\mu}Sv$ in measurement of Bone Scan patients with Pocket dosimeter. Significant difference found between Survey meter value and Pocket dosimeter value in all experimentation (p<0.001). Conclusion: Accoring to rusult Wearing Pocket dosimeter is usefulnee in manerage of exposed dose in nucler medicine exams.

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Study on Optimized Dispensing of F-18 FDG Auto Dispenser (F-18 FDG 자동분주기의 분주 최적화에 관한 연구)

  • Ji, Bong-Geun;Lee, Sang-Hun;Kim, Jong-Eon;Kim, Won-Tae;Ji, Tae-Jeong
    • 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.

Comparative Analysis between Preoperative Radiotherapy and Postoperative Radiotherapy in Clinical Stage I and II Endometrial Carcinoma (자궁내막암 환자에서 수술 전 방사선치료와 수술 후 방사선치료의 성적 비교 분석)

  • Keum Ki Chang;Lee Chang Geol;Chung Eun Ji;Lee Sang Wook;Kim Woo Cheol;Chang Sei Kyung;Oh Young Taek;Suh Chang Ok;Kim Gwi Eon
    • Radiation Oncology Journal
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    • v.13 no.4
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    • pp.377-383
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    • 1995
  • Purpose : To obtain the optimal treatement method in patients with endometrial carcinoma(clinical stage FIGO I, II) by comparative analysis between preoperative radiotherapy (pre-op RT) and postoperative radiotherapy (post-op RT). Material and Methods : A retrospective review of 62 endometrial carcinoma patients referred to the Yonsei Cancer Center for radiotherapy between 1985 and 1991 was undertaken. Of 62 patients, 19 patients(Stagel : 12 patients. Stagell;7 patients) received pre-op RT before TAH(Total Abdominal Hysterectomy) and BSO (Bilateral Salphingoophorectomy) (Group 1) and 43 patients(Stage 1;32 patients, Stage 2; 11 patients) received post-op RT after TAH and BSO (Group 2). Pre-op irradiation was given 4-6 weeks prior to surgery and post-op RT administered on 4-5 weeks following surgery. All patients except 1 patient(Group 2: ICR alone) received external irradiation. Seventy percent(13/19) of pre-op RT group and 54 percent(23/42) of post-op RT group received external pelvic irradiation and intracavitary radiation therapy(ICR). External radiation dose was 39.6-55 Gy(median 45 Gy) in 5-6. 5weeks through opposed AP/PA fields or 4-field box technique treating daily, five days per week, 180 cGy per fraction. ICR doses were prescribed to point A(20-39.6 Gy, median 39 Gy) in Group 1 and 0.5cm depth from vaginal surface (18-30 Gy,median 21 Gy) in Group 2. Results : The overall 5 year survival rate was $95{\%}$. No survival difference between pre-op and post-op RT group.($89.3{\%}$ vs $97.7{\%}$, p>0.1) There was no survival difference by stage, grade and histology between two groups. The survival rate was not affected by presence of residual tumor of surgical specimen after pre-op RT in Group 1 (p>0.1), but affected by presence of lymph node metastasis in post-op RT group(P<0.5). The complication rate of pre-op RT group was higher than post-op RT. ($16{\%}$ vs $5{\%}$) Conclusion : Post-op radiotherapy offers the advantages of accurate surgical-pathological staging and low complication rate.

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Chungkook-jang Koji Fermentation with Rice Straw (볏짚을 이용(利用)한 청국장 제조(製造)에 관(關)한 연구(硏究))

  • Kim, Kyung-Ja;Ryu, Myung-Ki;Kim, Sang-Soon
    • Korean Journal of Food Science and Technology
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    • v.14 no.4
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    • pp.301-308
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    • 1982
  • Chungkook-jang Koji was fermented with rice straw at $40^{\circ}C\;and\;50^{\circ}C$ for 72 hours. The changes of proximate composition, pH, titrable acidity, nitrogen compounds, protease activity and free-amino acids during the fermentation were investigated. Moisture, lipid and protein contents remained essentially unchanged during the fermentation. The pH was gradually increased from 6.4 to 7.46 and 7.82 at $40^{\circ}C\;and\;50^{\circ}C$, respectively, after 72 hour fermentation. Amino type and water soluble nitrogen increased as fermentation progressed. however, the former slightly decreased after 60 hour fermentation. Chungkook-jang fermented at $40^{\circ}C$ showed somewhat higher protease activity than $50^{\circ}C$. However, protease activity at both fermentation temperatures showed the same trend; that is, it increased until 48 hour fermentation and thereafter decrease. Free amino acid content of Chung-kook-jang after 72 hour fermentation at $40^{\circ}C$ was 6 times greater than that of the steamed soybean, while it was 2.5 times greater at $50^{\circ}C$. Based on these results. it seems that the optimum fermentation conditions for Chungkook-jang were $40^{\circ}C$ and 72 hours.

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Effects of the Feeding Platycodon grandiflorum and Codonopsis Ianceolata on the Lipid Components of Serum and Liver in Rats (도라지 및 더덕 첨가식이가 흰쥐의 혈청 및 간장의 지질성분에 미치는 영향)

  • 김소영;김한수;서인숙;이호신;김희숙;정승용
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.5
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    • pp.517-523
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    • 1993
  • This study was designed to observe the efforts of the feeding Platycodon grandiflorum, Codonopsis ianceolata, perilla oil and safflower oil on the improvement of the lipids in the serum and liver of dietary hypercholes-terolemic rats. Experimental groups mixed with 5% cellulose+10% lard (group 1, control group), 2% cholestyramine+10% lard (group 2), 5% C. Ianceolata+10% perilla oil (group3). 5% P. grandiflorum+10% perilla oil(group 4), 5% C. ianceolata+10% safflower oil(group 5) and 5% P. grandiflorum+10% safflower oil (group 6) were administered to the male rats of the Sprague Dawley for 3 weeks. Concentrations of total cholesterol in serum were significantly lower in the all experimental groups (2~6 groups) than in the control group, and particularly, the lowest in the group 2 and 6. Concentrations of HDL-cholesterol in serum were remarkably higher in the groups 2 and 4. The ratio of HDL-cholesterol to total cholesterol was the highest in the group 2. Atherosclerotic index was lower in the groups 2, 4 and 6. Concentrations of LDL, phospholipid and triglyceride in serum were remarkably lower in the all experimental groups than in the control group, and particularly, lower in the groups 2, 4 and 6. Concentrations of free cholesterol and cholesteryl ester in serum were significantly lower in the all experimental groups than in the control group, and particularly, the lowest in the group 2. Concentrations of glucose in blood were the lowest in the group 2. And groups 3 and 5 were slgnificantly lower. Contents of total cholesterol and triglyceride in liver were significantly lower in the all experimental groups than in the control group, and particularlyr the lowest in the groups 2 and 3. Phospholipid content was showed little differenre among groups but the lowest in the group 2. From the above research, the feeding 5% Platycodon grandiflorum+10% perilla oil and 5% Platycodon grandiflorum+10% safflower oil were effective on the improvement of the lipid compositions in serum and liver.

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Partial transmission block production for real efficient method of block and MLC (Partial transmission block 제작 시 real block과 MLC를 이용한 방법 중 효율적인 방법에 대한 고찰)

  • Choi JiMin;Park JuYoung;Ju SangGyu;Ahn JongHo
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.19-24
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    • 2004
  • Introduction : The Vaginal, the urethra, the vulva and anal cancer avoid the many dose to femur head and the additional treatment is necessary in inguinal LN. The partial transmission block to use inguinal LN addition there is to a method which it treats and produce partial transmission block a method and the MLC which to it analyzes. Material & Methode : The Inguinal the LN treatment patient partial transmission it used block and the MLC in the object and with solid water phantom with the patient it reappeared the same depth. In order to analyze the error of the junction the EDR2 (Extended dose range, the Kodak and the U.S) it used the Film and it got film scanner it got the beam profile. The partial transmission block and the MLC bias characteristic, accuracy and stability of production for, it shared at hour and comparison it analyzed. Result : The partial the transmission block compares in the MLC and the block production is difficult and production hour also above 1 hours. The custom the block the place where it revises the error of the junction is a difficult problem. If use of the MLC the fabrication will be break and only the periodical calibration of the MLC it will do and it will be able to use easily. Conclusion : The Inguinal there is to LN treatment and partial transmission block and the MLC there is efficiency of each one but there is a place where the junction of block for partial transmission block the production hour is caught long and it fixes and a point where the control of the block is difficult. like this problem it transfers with the MLC and if it treats, it means the effective treatment will be possible.

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