1.Evaluation of IMRT plans of prostate carcinoma from four treatment planning systems based on Monte Carlo
Zifeng CHI ; Chun HAN ; Dan LIU ; Yankun CA ; Runxiao LI
Chinese Journal of Radiation Oncology 2011;20(3):222-225
Objective With the Monte Carlo method to recaleulate the IMRT dose distributions from four TPS to provide a platform for independent comparison and evaluation of the plan quality.These results wiU help make a clinical decision as which TPS will be used for prostate IMRT planning.Methods Eleven prostate cancer cases were planned with the Corvus,Xio,Pinnacle and Eclipse TPS.The plans were recalculated bv Monte Cado using leaf sequences and MUs for individual plans.Dose-volume-histograms and isodose distributions were compared.Other quantities such as Dmin(the minimum dose received by 99% of CTV/PTV),Dmax(the maximum dose received by 1%of CTV/PTV),V110%,V105%,V95%(the volume of CTV/PTV receiving 110%,105%.95% of the prescription dose),the volume of rectum and bladder receiving>65 Gy and>40 Gy,and the volume of femur receiving>50 Gy were evaluated.Total segments and MUs were also compared.Results The Monte Carlo results agreed with the dose distributions from the TPS to within 3%/3 mm.The Xio,Pinnacle and Eclipse plans show less target dose heterogeneity and lower V65 and V40 for the rectum and bladder compared to the Corvus plans.The PTV Dmin is about 2 Gy lower for Xio plans than others while the Corvus plans have slightly lower female head V50(0.03%and 0.58%)than others.The Corvus plans require significantly most segments(187.8)and MUs(1264.7)to deliver and the Pinnacle plans require fewest segments(82.4)and MUs(703.6).Conclusions We have tested an independent Monte Carlo dose catculation system for dose reconstruction and plan evaluation.This system provides a platform for the fair comparison and evaluation of treatment plans to facilitate clinical decision making in selecting a TPS and beam delivery system for particular treatment sites.
2.Pertinence analysis of intensity-modulated radiation therapy dosimetry error and parameters of beams
Zifeng CHI ; Dan LIU ; Yankun GAO ; Runxiao LI ; Chun HAN
Chinese Journal of Radiological Medicine and Protection 2012;32(3):294-296
Objective To study the relationship between parameter settings in the intensity-modulated radiation therapy (IMRT) planning in order to explore the effect of parameters on absolute dose verification.Methods Forty-three esophageal carcinoma cases were optimized with Pinnacle 7.6c by experienced physicist using appropriate optimization parameters and dose constraints with a number of iterations to meet the clinical acceptance criteria.The plans were copied to water-phantem,0.13 cc ion Farmer chamber and DOSE1 dosimeter was used to measure the absolute dose.The statistical data of the parameters of beams for the 43 cases were collected,and the relationships among them were analyzed.The statistical data of the dosimetry error were collected,and comparative analysis was made for the relation between the parameters of beams and ion chamber absolute dose verification results.Results The parameters of beams were correlated among each other.Obvious affiliation existed between the dose accuracy and parameter settings.When the beam segment number of IMRT plan was more than 80,the dose deviation would be greater than 3% ; however,if the beam segment number was less than 80,the dose deviation was smaller than 3%.When the beam segment number was more than 100,part of the dose deviation of this plan was greater than 4%.On the contrary,if the beam segment number was less than 100,the dose deviation was smaller than 4% definitely.Conclusions In order to decrease the absolute dose verification error,less beam angles and less beam segments are needed and the beam segment number should be controlled within the range of 80.
4.Investigation of dose verification of esophageal carcinoma intensity modulated radiotherapy
Dan LIU ; Zifeng CHI ; Wei ZHANG ; Lan WANG ; Chun HAN
Chinese Journal of Radiation Oncology 2011;20(1):64-68
Objective To compare the results of three dose verification solutions of esophageal carcinoma IMRT plans. Methods Seven esophageal carcinoma cases were planned with Pinnacle 8.0 h.The MATRIXX and Delta4 were chosen as the two-dimensional dosimetry and three-dimensional dosimetry.IMRT plans and Delta4 phantom plans were also recalculated by Monte Carlo. Gamma values were evaluated for MATRIXX and Delta4 with 3 mm/3% gamma criteria. For the comparison of Pinnacle, Delta4 and Monte gamma maps, the dose distribution in central plane, dose profiles and dose-volume histograms were used to evaluate the agreement. Results The gamma maps comparison show that with 3 mm/3% gamma criteria an over 98% pass ratio was obtained by MATRIXX measurement. A 94. 4% gamma pass ratio whicl.contains 4 fields gamma pass ratio lower than 90%, was obtained by Delta4 measurement. A 97.6% and 99. 8% gamma pass ratio was obtained between the Delta4 measurement and Monte Carlo simulation with 2 mm/2% and 3 mm/3% gamma criteria. The dose distribution in central plane and dose profiles from Pinnacle calculation were almost in agreement with both the Monte Carlo simulation and Delta4 measurement. The DVH plot have slightly differences between Pinnacle and Delta4 measurement as well as Pinnacle and Monte Carlo simulation, but have excellent agreement between Delta4 measurement and Monte Carlo simulation. Conclusions It was shown that all the three methods can be used very efficiently to verify esophageal carcinoma IMRT delivery, Delta4 and Monte Carlo simulation no data missed. The primary advantage of Delta4 is the fact it can measure true 3D dosimetry while Monte Carlo can simulate in patients CT images but not in phantom.
5.Bilateral Frontal Polymicrogyria: An Autopsy Case Report.
Yi Kyeong CHUN ; Jong Sun CHOI ; Je G CHI
Korean Journal of Pathology 2011;45(Suppl 1):S62-S65
Bilateral frontal polymicrogyria is a recently recognized syndrome characterized by symmetric polymicrogyria of both frontal lobes that presents with delayed motor and language development, spastic quadriparesis, and variable mental retardation. However, the postmortem findings of this syndrome are not fully elaborated. Here we describe an autopsy case of bilateral frontal polymicrogyria in a male fetus delivered at 22 weeks gestation due to extensive chorioamnionitis. The microscopic findings included a thinned cortical plate with fair neuronal maturation. There were no signs of neuronal damage and the white matter was unremarkable.
Autopsy
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Chorioamnionitis
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European Continental Ancestry Group
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Female
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Fetus
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Frontal Lobe
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Humans
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Intellectual Disability
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Language Development
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Male
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Malformations of Cortical Development
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Muscle Spasticity
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Neuronal Migration Disorders
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Neurons
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Pregnancy
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Quadriplegia
7.Comparison of infrared mrker-based positioning system and electronic portal imaging device for the measurement of setup errors
Yankun CAO ; Chao GAO ; Lan WANG ; Zifeng CHI ; Chun HAN
Chinese Journal of Radiation Oncology 2011;20(5):414-416
ObjectiveTo measure the setup errors with infrared marker-based positioning system (IM-BPS) and electronic portal imaging device (EPID) for patients with esophageal carcinoma and lung cancer and investigate the accuracy and practicality of IM-BPS. MethodsFrom January 2007 to January 2008, 40 patients with esophageal carcinoma and 27 patients with lung cancer received three-dimensional conformal radiotherapy or intensity-modulated radiotherapy, setup errors during the treatment were measured with IM-BPS and EPID, and the data of setup errors were compared with paired t-test and agreement with x2-test. ResultsIt takes 10 - 12 mins to complete the validating for each patient by EPID) system, while IMBPS system only needs 2 -5 mins. The mean setup errors along x, y and z-axis for patients with esophageal carcinoma measured by IM-BPS and EPID were 3.49 mm, 3. 19 mm, 3.31 mm and 4. 03 mm, 3.41 mm, 3.43 mm, respectively. For the patients with lung cancer, the setup errors were 4. 23 mm, 3.51 mm, 3. 39mm and 4. 85 mm, 3. 53 mm, 3.74 mm, respectively. The difference of setup errors meanured by the two systems was within 1 mm for 65% esophageal carcinoma patients ( x2 =51.09, P =0. 000), and 55% lung cancer patients ( x2 =53. 35, P =0. 000).Conclusions The measurement results of setup errors for patients with esophageal carcinoma and lung cancer show that IM-BPS is mostly better than EPID. Though validating for patients can be measured accurately and be well quality controlled, IM-BPS is used easily because of macroscopic, homely,spare time and real-time monitoring.
8.Investigation of the current situation of systematically holistic nursing in hospitals
Chinese Journal of Modern Nursing 2010;16(11):1287-1289
Objective To investigate the current situation of systematically holistic nursing in hospitals. Methods A total of 285 nurses from 6 first-class Grade 3 hospitals were investigated with a selfdesigned questionnaire in terms of current situation of systematically holistic nursing in hospitals. Results The present situation of systematically holistic nursing was not satisfactory, factors such as unreasonable allocation of human resources, low overall quality of the nursing team, imperfect assistant support system and nursing managers' paradigm problem had badly affected the thorough development of the systematic approach to holistic nursing. Conclusions We should change our conception and try to innovate according to China' s actual conditions, create a Chinese nursing way and our own nursing brand based on drawing lessons from advanced nursing model of other countries to realize the value of nursing.
9.Four Cases of Intrapulmonary Hamartoma: An ultrastructural study.
Ho Jong CHUN ; Keun Hong KEE ; Chae Hong SUH ; Jang Sihn SOHN ; Chung Hee CHI
Korean Journal of Pathology 1988;22(1):70-81
Tumors of the lung and bronchi containing cartilage were known by a variety of names, chondroma, adenochondroma, chondromatous hamartoma and mixed tumor. This variation in nomenclatures explain the difference of illustration on the nature of these tumor. The concept pulmonary harmatomas are benign neoplasm and not developmental malformations, has gained wide acceptance in recent years. We have experienced four cases of intrapulmonary hamartoma which were all discovered during routine chest film check up for certificate of health and evaluation of other disease. One case is added further detailed histologic examination by electron microscopy. The age at time of the detection were 53 (male), 23 (male), 39 (female), and 56 (female) years old. The mean size is 4.3x3.7x3.4 cm. The locations were three left upper lobes and one right upper lobe. Lobectomy and wedge resecions were done. Cut surface showed promiment lobular structures, papillary configuration and multiple cleft like spaces. Predominant cellular components were cartilage but fat tissue in one of the four cases. Microscopic findings showed abundant hyaline cartilages bearing lobular configuration and overlying pseudostratified ciliated columnar and cuboidal epithelium. Fibromyxoid and undifferentiated cells were seen in myxoid and fatty tissue. Electron microscopic findings revealed stellate, undifferentiated mesenchymal cells bearing collagen formation, stellate smooth muscle and transition areas between undifferentiated mesenchymal cells and mature cartilage. Epithelial components were similar to terminal bronchiole and alveolar epithelium. These findings suggest the concept that intrapulmonary hamartoma represent a histologic specturm of benign mesenchymal neoplasms, which originate in peribronchial connective tissue.
Female
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Male
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Humans
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Hamartoma
10.A clinical analysis of laser laparoscopic cholecystectomy.
Kyung Soo YU ; Kyung Chun CHI ; Jung Hyo LEE ; In Taik CHANG ; Sang Jhoon KIM
Journal of the Korean Surgical Society 1992;42(3):313-319
No abstract available.
Cholecystectomy, Laparoscopic*