• Title/Summary/Keyword: Fraction

Search Result 12,925, Processing Time 0.135 seconds

Modification of Late Radiation Response of Rat Salivary Glands by Pentoxifylline and Diltiazem (쥐의 타액선 방사선조사 후 만성반응에 Pentoxifylline과 Diltiazem이 미치는 영향)

  • Suh, Hyun-Suk;Yang, Kwang-Mo;Kang, Yun-Kyung
    • Radiation Oncology Journal
    • /
    • v.17 no.3
    • /
    • pp.230-237
    • /
    • 1999
  • Purpose : To elucidate the effects of pentoxifylline and diltiazem on the late response of the salivary glands of the rat after irradiation. Materials and Methods : Sixteen Sprague-Dawley rats were divided into 4 groups : (a) irradiation alone (b) irradiation with pentixifylline (PTX) (c) irradiation with diltiazem (DTZ) (d) irradiation with both PTX and DTZ. Irradiation was given in a single fraction of 16 Gy using 4 MV photon energy through an anterior port encompassing the left side of the salivary gland leaving the right side of salivary gland as a control. PTX, 20 mg/kg and/or DTZ, 50 mg/kg were infused intraperitoneally before irradiation, Two rats from each group were sacrificed on the 10th week and the rest was sacrificed on the 16th week after irradiation. Histopathologic examinations were undertaken for each section and the proportion of vacuolated cells out of the total number of cells under light microscopic fields was calculated. The statistical significance in the difference of the proportion of the vacuolated cells among the experimental groups was evaluated by a $x^2$-test. Results : Irradiated salivary glands of the 10th week group revealed markedly increased number of vacuolated cells compared to those of unirradiated control. The proportion of vacuolated cells was significantly reduced in both the PTX group (p value=0.001) and the combined PTX and DTX group compared to those of irradiation alone group. The DTZ alone group did not reveal the significant reduction of vacuolated cells compared to those of irradiation alone group (p value, >0.05). The 16th week groups revealed similar findings to those of the 10th week group, but the degree of chronic inflammatory cell infiltrates and interstitial fibrosis was increased and the number of acinar cells was reduced compared to those of the 10th week group. Conclusions : PTX significantly reduced the late radiation response of salivary glands, but DTZ did not reduce the same degree as PTX did. Taking the positive results of this study into consideration, it seems reasonable to apply PTX into the clinical trial for the head and neck irradiation to reduce the late radiation sequelae of salivary glands in the near future. At the same time the further experiment to clarify the subcellar mechni는 involved in PTX should be preceded.

  • PDF

Hyperfractionation Radiation Therapy in Advanced Head and Neck Cancer (진행된 두경부암에서 다분할 방사선치료)

  • Kim, Jin-Hee;Ye, Ji-Won
    • Radiation Oncology Journal
    • /
    • v.21 no.2
    • /
    • pp.112-117
    • /
    • 2003
  • Purpose: The effects of hypefractionation radiation therapy, such as the failure pattern and survival, on the treatment results in advanced stage head and neck cancer were studied. Materials and Methods: Between September 1990 and October 1998, 24 patients with advanced stage (III, IV) head and neck cancers, were treated using hyperfractionation radiation therapy in the Department of Radiation Oncology at the Keimyung University Dongsan Medical Center. The male to female ratio was 7 : 1, and the age range from 38 to 71 years with the median of 56 years. With regard to the TNM stage, 11 patients were stage III and 13 were stage IV. The sites of primary cancer were the nasopharynx in six, the hypopharynx in 6, the larynx in five, the oropharynx in three, the maxillary sinus in three, and the oral cavity in one patient. The radiotherapy was delivered by 6 MV X-ray, with a fraction size of 1.2 Gy at two fractions a day, with at least 6 hours inter-fractional interval. The mean total radiation doses was 72 Gy, (ranging from 64.4 to 75.8 Gy). Follow-up periods ranged between 3 and 136 months, with the median of 52 months. Results: The overall survival rates at 3 and 5 years in all patients were 66.7$\%$, and 52.4$\%$. The disease-free survival rates at 3 and S years (3YDFS, 5YDFS) in all patients were 66.7$\%$ and 47.6$\%$. The 3YDFS and 5YDFS in stage III patients were 81.8$\%$ and 63.6$\%$, and those in stage IV patients were 53.8$\%$ and 32.3$\%$. Ten patients were alive with no local nor distant failures at the time of analyses. Six patients (25$\%$) died due to distant metastasis and 12.5$\%$ died due to local failure. Distant metastasis was the major cause of failure, but 2 patients died due to unknown failures and 3 of other diseases. The distant metastasis sites were the lung (3 patients), the bone (1 patient), and the liver (2 patients). One patient died of second esophageal cancer. There were no severe late complications, with the exception of 1 osteo-radionecrosis of the mandible 58 months after treatment. Conclusion: Although this study was peformed on small patients group, we considered hypefractionated radiation therapy for the treatment of advanced stage head and neck cancer might improve the disease free survival and decrease the local failure with no increase in late complications despite of the slight Increase in acute complications.

The Results of Postoperative Radiotherapy for Endometrial Carcinoma (자궁 내막암의 수술 후 방사선치료 결과)

  • Noh, O-Kyu;Lee, Sang-Wook;Ahn, Seung-Do;Choi, Eun-Kyung;Kim, Jong-Hyeok;Kim, Yong-Man;Nam, Joo-Hyun;Mok, Jung-Eun;Kim, Jong-Hoon;Shin, Seong-Soo
    • Radiation Oncology Journal
    • /
    • v.25 no.2
    • /
    • pp.93-100
    • /
    • 2007
  • [ $\underline{Purpose}$ ]: To evaluate the outcome and prognostic factors of postoperative radiotherapy in endometrial carcinoma. $\underline{Materials\;and\;Methods}$: From September 1991 to August 2003, 76 patients with endometrial carcinoma received postoperative adjuvant radiotherapy after hysterectomy at Asan Medical Center. Stage was classified as FIGO I in 41 (53.9%), II in 12 (53.9%), and III in 23 (30.3%). Histologic grade 1, 2 and 3 were in 29 (38.2%), 20 (26.3%), and 27 (35.5%) respectively. Forty two patients received both external beam radiation therapy (EBRT) and intracavitary radiation (ICR), 34 patients were treated with EBRT or ICR alone. EBRT dose was 50.4 Gy, ICR was performed in $4{\sim}6$ fractions with $4{\sim}5\;Gy$ per fraction. Median follow-up period was 51 (range $5{\sim}121$) months. $\underline{Results}$: Five-year overall survival was 89.6%. In univariate analysis, statistically significant factors to overall survival were FIGO stage, lymph node metastasis and histologic grade. In disease free survival, FIGO stage, lymph node metastasis and lymphovascular invasion were significant prognostic factors. Recurrence was seen in 11 patients. Of these, systemic failure was in 10 patients. There were no moderate to severe complications after radiation therapy. $\underline{Conclusion}$: The outcome of postoperative adjuvant radiotherapy in endometrial carcinoma was good. Main pattern of failure after postoperative radiotherapy was distant metastasis. So, adjuvant chemotherapy may help in improving outcome. Further study on chemotherapy in combined with postoperative radiotherapy will be needed, especially for patients with high risk factors such as high FIGO stage, lymphovascular invasion, and high histologic grade.

The Relation between Collateral Circulation and $^{99m}Tc$-MIBI Heart SPECT (심근경색에서 측부순환 유무에 따른 $^{99m}Tc$-MIBI 심근 SPECT 소견)

  • Kim, Jae-Man;Na, Deug-Young;Park, Eun-Kyung;Yang, Hyung-In;Kim, Deog-Yoon;Kang, Heung-Sun;Choue, Chung-Whee;Kim, Kwon-Sam;Kim, Myung-Shick;Song, Jung-Sang;Bae, Jong-Hoa
    • The Korean Journal of Nuclear Medicine
    • /
    • v.28 no.1
    • /
    • pp.37-43
    • /
    • 1994
  • The coronary collateral vessels have revealed their significance in terms of reduction of infarct size, preservation left ventricular function, and prevention of left ventricular aneurysm in patients with myocardial infarction. The purpose of this study were to evaluated the relation between collateral circulation and $^{99m}Tc$-MIBI Heart SPECT in patient with acute myocardial infarction and their clinical significance. The fifty six MI patients with antegrade TIMI perfusion grade 0 and 1 were studied. The patients were classified into two groups; Group I inclueded 30 patients with grade 2, 3 Collateral flow. Group II inclueded 26 patients with grade 0, 1 Collateral flow. Collateral filling were graded from 0 to 3: 0- none, 1- Filling of side branch only, 2- Partial filling of the epicardial segment, 3- Complete filling of epicardial segment. Clinical variables, left ventricular function, $^{99m}Tc$-MIBI Heart SPECT were analyzed with angiographic finding. Results were following: 1) Collateral visualization was found to be greater in patient with involvement of right coronary artery (RCA). The collateral development site of infarct related artery was RCA 15 cases, left anterior descending artery (LAD) 10 cases, left circumflex artery (LCX) 5 cases, and the collateral circulation from LAD to RCA was 13 cases (40.6%). 2) There was a tendency to be decreased in peak CK activity with group I. 3) The presence of good collateral channels was more frequently $^{99m}Tc$-MIBI reversible perfusion defect (83.4% vs 15.3%, p<0.05). 4) No differences of left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), ejection fraction (EF) were noted between group I and group II. The presence of good collateral channels did affect the frequency of occurrence of $^{99m}Tc$-MIBI reversible perfusion defect.

  • PDF

Phase Image Analysis in Conduction Disturbance Patients (심실내 전도장애 환자에서의 $^{99m}Tc$-RBC Gated Blood-Pool Scintigraphy을 통한 Phase Image Analysis)

  • Kwak, Byeng-Su;Choi, Si-Wan;Kang, Seung-Sik;Park, Ki-Nam;Lee, Kang-Wook;Jeon, Eun-Seok;Park, Chong-Hun
    • The Korean Journal of Nuclear Medicine
    • /
    • v.28 no.1
    • /
    • pp.44-51
    • /
    • 1994
  • It is known that the normal His-Purkinje system provides for nearly synchronous activation of right (RV) and left (LV) ventricles. When His-Purkinje conduction is abnormal, the resulting sequence of ventricular contraction must be correspondingly abnormal. These abnormal mechanical consequences were difficult to demonstrate because of the complexity and the rapidity of it's events. To determine the relationship of the phase changes and the abnormalities of ventricular conduction, we performed phase image analysis of $^{99m}Tc$-RBC gated blood pool scintigrams in patients with intraventricular conduction disturbances (24 complete left bundle branch block (C-LBBB), 15 complete right bundle branch block (C-RBBB), 13 Wolff-Parkinson-White syndrome (WPW), 10 controls). The results were as follows; 1) The ejection fraction (EF), peak ejection rate (PER), and peak filling rate (PFR) of LV in gated blood pool scintigraphy (GBPS) were significantly lower in patients with C-LBBB than in controls ($44.4{\pm}13.9%$ vs $69.9{\pm}4.2%,\;2.48{\pm}0.98$ vs $3.51{\pm}0.62,\;1.76{\pm}0.71$ vs $3.38{\pm}0.92$, respectively, p<0.05). 2) In the phase angle analysis of LV, Standard deviation (SD), width of half maximum of phase angle (FWHM), and range of phase angle were significantly increased in patients with C-LBBB than in controls ($20.6{\pm}18.1$ vs $8.6{\pm}1.8,\;22.5{\pm}9.2$ vs $16.0{\pm}3.9,\;95.7{\pm}31.7$ vs $51.3{\pm}5.4$, respectively, p<0.05). 3) There was no significant difference in EF, PER, PFR between patients with the Wolff-parkinson-White syndrome and controls. 4) Standard deviation and range of phase angle were significantly higher in patients with WPW syndrome than in controls ($10.6{\pm}2.6$ vs $8.6{\pm}1.8$, p<0.05, $69.8{\pm}11.7$ vs $51.3{\pm}5.4$, p<0.001, respectively), however, there was no difference between the two groups in full width of half maximum. 5) Phase image analysis revealed relatively uniform phase across the both ventricles in patients with normal conduction, but markedly delayed phase in the left ventricle of patients with LBBB. 6) In 13 cases of WPW syndrome, the site of preexcitation could be localized in 10 cases (77%) by phase image analysis. Therefore, it can be concluded that phase image analysis can provide an accurate noninvasive method to detect the mechanical consequences of a wide variety of abnormal electrical activation in ventricles.

  • PDF

Sedimentological Characteristics of Surface Sediments in the Southwestern Sea off Cheju Island, Korea (제주도 서남해역의 해저퇴적물 특성)

  • Youn, Jeung-Su;Kim, Soung-Bok;Koh, Gi-Won
    • 한국해양학회지
    • /
    • v.24 no.3
    • /
    • pp.132-147
    • /
    • 1989
  • A total of 83 surface sediments and 55 sea water samples, collected from the southwestern sea of Cheju Island, were analyzed in order to understand their textural characteristics, geochemical composition and the clay mineralogical features. The sediments were subdivided into ten textural classes, namely clayey sand, slightly gravelly muddy sand, sandy clay, clay and mud. The coarse and fine-grained mixed sediments are distributed in the northern part and around the Island, whereas the fine-grained deposits are mainly distributed in the central and southern parts of the study area; small scale mud patches are distributed in the southwestern and northern parts of Cheju Island. The high concentration of total suspended matter in study area gradually increase toward the southwestern and northwestern offshore area. The concentration of geochemical elements is as follow: the content of Mn, Al, Zn, Cr, Cu and Sn increase toward the southern part which is covered mainly with fine-grained deoposits, whereas the content of Ca, Mg and Ag is higher in the northern area; the elements such as Ni, Na, Fe and Pb are more concentrated relatively in muddy deposits rather than in sandy sediments. The light minerals such as Na-Ca feldspars show a high content around the Socotra Rock, toward the Soheugsan and Cheju Islands, but the K-feldspars are relatively high around the Cheju Island. It was noticed that the provenance of these sediments is partly influenced by the geological characteristics near the island. X-ray diffractogram for clay minerals from the southeastern mud patch and around the Soheugsan Island shows the diagnostic calcite peak indicating that the greater part of these clay fraction may have been derived from present and ancient Hwangho River. The high concentration of smectite in the northern part near the Cheju and around the Soheugsan Islands, eastern side of Socotra Rock probably result from supplies smectite altered from volcanic materials distributed in the Cheju Island and Socotra Rock, whereas the samples near the Chuja and northern parts of the Cheju Island contain weak calcite peak and high concentration of kaolinite and chlorite which is closely related to the geolgical characteristics on the adjacenting land area.

  • PDF

Tidal-Flat Sedimentation in a Semienclosed Bay with Erosional Shorelines: Hampyong Bay, West Coast of Korea (해안침식이 우세한 반폐쇄적 조간대의 퇴적작용: 한국 서해안의 함평만)

  • Chang, Jin-Ho;Kim, Yeo-Sang;Cho, Yeong-Gil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.4 no.2
    • /
    • pp.117-126
    • /
    • 1999
  • Hampyong Bay is a semienclosed and macrotidal bay which opens to the eastern Yellow Sea through a narrow inlet in the southwestern coast of Korea. In order to understand the tidal-flat sedimentation in the semienclosed setting, morphology, sediments, accumulation rate and sea cliff erosion were investigated in the tidal flat of Hampyong Bay. The tidal flat of Hampyong Bay lacks intertidal drainage systems, and generally shows the concave-upward profile whose relief is designated by marked morphological features such as high-tide beaches, intertidal sand shoals and tidal creeks. Surfacial sediments of the tidal flat mainly consist of mud, sandy mud, gravelly mud, gravelly sand and muddy gravel, thus showing the textural characteristics of multimodal grain-size distribution, poorly sorting and positive skewness. The sediments generally coarsen landward due to the increase in coarse fraction content. Sedimentary structures are deeply bioturbated, but parallel lamination and lenticular bedding are locally found in the mudflat near mean low water line. Annual accumulation rates across the tidal flat (along Line SM) average -5.2 cm/yr with a range of -45.8~+4.2 cm/yr, indicating that the tidal flat is erosional. In general, erosion rates of upper and lower tidal flat are higher than those of middle tidal flat. Seasonally, the erosion rates are much higher during spring and winter when dominant wind direction corresponds to the long axis of Hampyong Bay. Sea cliffs are eroded at a rate of 1.4 m/yr. The biggest sea cliff erosion generally occurs 1~2 months later after tidal flats were extensively eroded. Such erosions of tidal Oats and sea cliffs in the semienclosed bay setting are interpreted to be due to wind waves coupled with local sea-level rise.

  • PDF

Early Hemodynamic Changes and Short-term Outcomes of Mitral Valvuloplasty versus Replacement with Chordal Preservation for Patients with Mitral Regurgitation (승모판막폐쇄부전 환자에서 판막성형술과 판막대치술이 수술 후 혈역학과 단기 예후에 미치는 영향 비교)

  • Choi, Yong-Seon;Kwak, Young-Lan;Chang, Byung-Chul;Kim, Ji-Ho;Hong, Yong-Woo;Bang, Sou-Ouk
    • Journal of Chest Surgery
    • /
    • v.40 no.10
    • /
    • pp.659-666
    • /
    • 2007
  • Background: Preserving the subvalvular apparatus after mitral valve replacement (MVR) results in better ventricular function and a better outcome. In conjunction, mitral valve repair (MVr) is associated with a better outcome, yet little is known about the hemodynamics and outcomes between patients undergoing MVr and MVR with chordal preservation. We prospectively evaluated the hemodynamic changes and outcomes of patients undergoing MVr and MVR with chordal preservation. Material and Method: Fifty-four patients with mitral regurgitation (MR) who under-went MVR with chordal preservation (n=21) or MVr (n=33) were studied. The patients' characteristics, the intra-and postoperative hemodynamics and the use of cardiac medications, the postoperative outcome and the complications were recorded during the hospital stay. All the patients were followed up for at least 6 months post-operatively for determining their morbidity and mortality. Result: The patients' characteristics were similar between the groups, except for the presence of atrial fibrillation and congestive heart failure which was more frequent in the MVR group. Also, the preoperative left ventricular ejection fraction was lower in the MVR group than in the MVr group ($64{\pm}9%$ versus $69{\pm}5%$, respectively, p=0.043). There were no significant differences of the hemodynamics between the groups. The use of inotropic drugs and pacemakers during the 12hrs postoperatively was more common in the MVR group than in the MVr group (48% versus 24%, p=0.025 and 52% versus 24%, p=0.035, respectively). The other postoperative outcomes were similar in both groups for at least the 6 months follow-up period. Conclusion: MVR with chordal preservation was comparable with regard to the hemodynamics and clinical outcomes, supporting the beneficial effect of preserving the subvalvular apparatus after MVR.

Changes of Mitral Regurgitation after Aortic Valve Replacement, according to the Aortic Valve Pathology (대동맥 판막 치환술 후 대동맥 판막 병변에 따른 승모판막 폐쇄부전의 변화)

  • Kim, Si-Wook;Lee, Young-Tak;Jun, Tae-Gook;Sung, Ki-Ick;Kim, Wook-Sung;Yang, Ji-Hyuk;Choi, Jin-Ho;Park, Pyo-Won
    • Journal of Chest Surgery
    • /
    • v.40 no.10
    • /
    • pp.667-673
    • /
    • 2007
  • Background: Patients with severe aortic valve disease frequently display mitral valve regurgitation (MR). In such patients, the clinical course of MR after isolated aortic valve replacement (AVR) may be important for determining the treatment strategies. After isolated AVR, the change of the concomitant moderate degree or less of MR according to the type of aortic valve disease is not known well. The aim of this study was to analyze the post-operative changes of MR after performing AVR in those patients with severe AS (Group S) and those with severe AR (Group R). Material and Method: We retrospectively evaluated 43 patients with severe aortic disease and a moderate degree or less of mitral valve regurgitation, and these patients underwent isolated aortic valve replacement from January 1996 to June 2005. The patients were divided into two groups: the aortic valve stenosis group (n = 29) and the aortic valve regurgitation group (n = 14). The patients underwent transthoracic echocardiography preoperatively and at 7 days, $6{\sim}10$ months and more than 18 months (mean follow-up duration: 38 months) postoperatively. Result: The mean age was 60.9 years (Group S: 62 years, Group R: 52.5 years) and 60% (Group S=55%, Group R=71%) of the patients were male. The preoperative MR was mild in 29 (67.5%), mild to moderate in 11 (25.5%), and moderate in 3 (6.9%) patients. In the Group S patients, MR improved in 16 (55%) patients at the immediate postoperative days and in 17 (59%) patients at more than 18 months postoperatively. On the other hand, all the Group R patients exhibited earlier improvement. The decrease of LA size had a similar pattern to the MR change, but there were no significant differences in the change of the ejection fraction of the two groups. Conclusion: In the patients with severe aortic valve disease and concomitant low grade MR, the MR after AVR improved earlier and more effectively in the patients with AR than in those patients with AS.

Assessment of Parameters Measured with Volumetric Pulmonary Artery Catheter as Predictors of Fluid Responsiveness in Patients with Coronary Artery Occlusive Disease (관상동맥 질환을 가진 환자에서 폐동맥카테터로 측정한 전부하 지표들은 수액부하 반응을 예상할 수 있는가?)

  • Lee, Ji-Yeon;Lee, Jong-Hwa;Shim, Jae-Kwang;Yoo, Kyung-Jong;Hong, Seung-Bum;Kwak, Young-Lan
    • Journal of Chest Surgery
    • /
    • v.41 no.1
    • /
    • pp.41-48
    • /
    • 2008
  • Background: Accurate assessment of the preload and the fluid responsiveness is of great importance for optimizing cardiac output, especially in those patients with coronary artery occlusive disease (CAOD). In this study, we evaluated the relationship between the parameters of preload with the changes in the stroke volume index (SVI) after fluid loading in patients who were undergoing coronary artery bypass grafting (CABG). The purpose of this study was to find the predictors of fluid responsiveness in order to assess the feasibility of using. certain parameters of preload as a guide to fluid therapy. Material and Method: We studied 96 patients who were undergoing CABG. After induction of anesthesia, the hemodynamic parameters were measured before (T1) and 10 min after volume replacement (T2) by an infusion of 6% hydroxyethyl starch 130/0.4 (10 mL/kg) over 20 min. Result: The right ventricular end-diastolic volume index (RVEDVI), as well as the central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP), failed to demonstrate significant correlation with the changes in the SVI (%). Only the right ventricular ejection fraction (RVEF) measured at T1 showed significant correlation. with the changes of the SVI by linear regression (r=0.272, p=0.017). However, when the area under the curve of receiver operating characteristics (ROC) was evaluated, none of the parameters were over 0.7. The volume-induced increase in the SVI was 10% or greater in 31 patients (responders) and under 10% in 65 patients (non-responders). None of the parameters of preload measured at T1 showed a significant difference between the responders and non-responders, except for the RVEF. Conclusion: The conventional parameters measured with a volumetric pulmonary artery catheter failed to predict the response of SVI following fluid administration in patients suffering with CAOD.