• Title/Summary/Keyword: transient operation

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Effects of Fractionated Stereotactic Radiotherapy for Primary Hepatocellular Carcinoma (원발성 간암의 분할 정위방사선치료 효과)

  • Choi Byeong Ock;Kang Ki Mun;Jang Hong Seok;Lee Snag-wook;Kang Young Nam;Chai Gyu Young;Choi Ihl Bhong
    • Radiation Oncology Journal
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    • v.23 no.2
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    • pp.92-97
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    • 2005
  • Purpose : Reports on the outcome of curative radiotherapy for the primary hepatocellular carcinoma (HCC) are rarely encountered in the literature. in this study, we report our experience of a clinical trial where fractionated stereotactic radiotherapy (SRT) was used in treating a primary HCC. Materials and Methods : A retrospective analysis was peformed on 20 patients who had been histologically diagnosed as HCC and treated by fractionated SRT. The long diameter of tumor measured by CT was $2\~6.5$ cm (average: 3.8 cm). A single dose of radiation used in fractionated SRT was S or 10 Gy: each dose was prescribed based on the planning target volume and normalized to $85\~99\%$ isocenter dose. Patients were treated $3\~5$ times per week for 2 weeks, with each receiving a total dose of 50 Gy (the median dose: 50 Gy). The follow up period was $\~55$ months (the median follow up period: 23 months). Results : The response rate was $50\%$ (12 patients), with 4 patients showing complete response ($20%$), 8 patients showing partial response ($40\%$), and 8 patients showing stable disease ($40\%$). The 1-year and 2-year survival rates were $70.0\%$ and $43.1\%$, respectively, and the median survival time was 20 months. The 1-year and 2-year disease free survival rates were $65\%$ and $32.5\%$, respectively, and the median disease-free survival rate was 19 months. Some acute complications of the treatment were noted as follows: dyspepsia in 12 patients ($60\%$), nausea/emesis in 8 patients ($40\%$), and transient liver function impairment in 6 patients ($30\%$). However, there was no treatment related death. Conclusion : The study indicates that fractionated SRT is a relatively safe and effective method for treating primary HCC. Thus, fractionated SRT may be suggested as a local treatment for HCC of small lesion and containing a single lesion, when the patients are inoperable or operation is refused by the patients. We thought that fractionated SRT is a challenging treatment modality for the HCC.

Development of Automatic Loading Equipment of Seedling Tray for Automatic Process of Raising Seedlings in Plant Factory (식물공장 육묘공정 자동화를 위한 육묘트레이 자동적재장치 개발)

  • Park, Sang-Min;Min, Young-Bong;Lee, Gong-In;Kim, Dong-Ouk;Kang, Dong-Hyun;Moon, Sung-Dong
    • Journal of agriculture & life science
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    • v.45 no.5
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    • pp.105-113
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    • 2011
  • This study was carried out to develop an automatic loading equipment that can load seedling trays on loading position of the seedling bed driving on enclosed-type rail installed for interconnecting each process of raising seedlings in plant factory. The experiment of transferring the seedling tray by monorail pusher was carried out to figure out the required transfer force and problems during push type device of transporting the plastic seedling trays, that has completed its sowing process, which are installed onto the board of different materials. From the results of this experiment, the loading equipment which can exactly load three of the seedling trays orderly on the loading position of the seedling bed was designed and made. When three sowed trays on every board are transferred by pusher with the speed is at 30 cm/s, the maximum peak transfer force with maximum overshooting at initial transient state and the maximum transfer force at stead state are were respectively 32.8 N, 29.4 N on rubber board, 29.7 N, 22.5 N on a wooden board, 26.9 N, 19.6 N on a acrylic board, and 27.6 N, 19.1 N on an iron board. Changes in the transfer force occurred its maximum at the moment when the pusher collided with the tray, after the collision gradually decreased until it became stable. When two or three trays placed it in order of widthwise are transferred, it is occurred the overlapping of the tray's external bracket. The developed automatic loading equipment with PLC controller did not make any operation error through 100 times of tests, its maximum seedling tray loading speed was 2 sec/tray and its maximum error of transferred location of the tray was 0.5 cm.

Assessment of Cerebral Hemodynamic Changes in Pediatric Patients with Moyamoya Disease Using Probabilistic Maps on Analysis of Basal/Acetazolamide Stress Brain Perfusion SPECT (소아 모야모야병에서 뇌확률지도를 이용한 수술전후 혈역학적 변화 분석)

  • Lee, Ho-Young;Lee, Jae-Sung;Kim, Seung-Ki;Wang, Kyu-Chang;Cho, Byung-Kyu;Chung, June-Key;Lee, Myung-Chul;Lee, Dong-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.3
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    • pp.192-200
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    • 2008
  • To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Methods: Total fifty six (M:F = 33:24, age $6.7{\pm}3.2$ years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was $33{\pm}21$ months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. Results: In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal lobe of the hemispheres with EDAS and frontal EGS, the post-operative CVRI, and ${\Delta}CVRI$ showed a significant difference between patients with a good and poor clinical outcome (p<0.05). In a multivariate logistic regression analysis, the ${\Delta}CVRI$ and the post-operative CVRI of medial frontal gyrus on the hemispheres where EDAS with frontal EGS was performed were the significant predictive factors for the clinical outcome (p =0.002, p =0.015), Conclusion: With probabilistic map, we could objectively evaluate pre/post-operative hemodynamic changes of pediatric patients with moyamoya disease. Specifically the post-operative CVRI and the post-operative CVRI of medial frontal gyrus where EDAS with frontal EGS was done were the significant predictive factors for further clinical outcomes.

Risk Factor Analysis for Operative Death and Brain Injury after Surgery of Stanford Type A Aortic Dissection (스탠포드 A형 대동맥 박리증 수술 후 수술 사망과 뇌손상의 위험인자 분석)

  • Kim Jae-Hyun;Oh Sam-Sae;Lee Chang-Ha;Baek Man-Jong;Hwang Seong-Wook;Lee Cheul;Lim Hong-Gook;Na Chan-Young
    • Journal of Chest Surgery
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    • v.39 no.4 s.261
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    • pp.289-297
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    • 2006
  • Background: Surgery for Stanford type A aortic dissection shows a high operative mortality rate and frequent postoperative brain injury. This study was designed to find out the risk factors leading to operative mortality and brain injury after surgical repair in patients with type A aortic dissection. Material and Method: One hundred and eleven patients with type A aortic dissection who underwent surgical repair between February, 1995 and January 2005 were reviewed retrospectively. There were 99 acute dissections and 12 chronic dissections. Univariate and multivariate analysis were performed to identify risk factors of operative mortality and brain injury. Resuit: Hospital mortality occurred in 6 patients (5.4%). Permanent neurologic deficit occurred in 8 patients (7.2%) and transient neurologic deficit in 4 (3.6%). Overall 1, 5, 7 year survival rate was 94.4, 86.3, and 81.5%, respectively. Univariate analysis revealed 4 risk factors to be statistically significant as predictors of mortality: previous chronic type III dissection, emergency operation, intimal tear in aortic arch, and deep hypothemic circulatory arrest (DHCA) for more than 45 minutes. Multivariate analysis revealed previous chronic type III aortic dissection (odds ratio (OR) 52.2), and DHCA for more than 45 minutes (OR 12.0) as risk factors of operative mortality. Pathological obesity (OR 12.9) and total arch replacement (OR 8.5) were statistically significant risk factors of brain injury in multivariate analysis. Conclusion: The result of surgical repair for Stanford type A aortic dissection was good when we took into account the mortality rate, the incidence of neurologic injury, and the long-term survival rate. Surgery of type A aortic dissection in patients with a history of chronic type III dissection may increase the risk of operative mortality. Special care should be taken and efforts to reduce the hypothermic circulatory arrest time should alway: be kept in mind. Surgeons who are planning to operate on patients with pathological obesity, or total arch replacement should be seriously consider for there is a higher risk of brain injury.