WorldWideScience

Sample records for rate endovascular irradiation

  1. Endovascular Irradiations with beta sources

    Energy Technology Data Exchange (ETDEWEB)

    Scmidt, W F.O.; Hawliczek, R [Inst of Radiooncology IRO, Donauspital, Vienna (Austria); Mueck, K [Austrian Research Centre, Siebersdorf ARCS (Austria); Lehmann, D [Inst of Radiotherapy, Univ. Dresden (Germany); Pichler, L [Ludwig Boltzmann Institute for Endovascular Radiotherapy, Donauspital, Vienna (Austria)

    1999-12-31

    For treatment of restenoses tubes (inner/outer diameter 1 and 2 mm; length 3 or 5 mm) with Y-90 foils, shielded by Ti-layers on all sides have been developed (activity 0.5 - 2 GBq). Quality checks with plastic scintillators have been developed and are correlated to absolute dose measurements performed with TLDs (1x1 mm2; 40 mg/cm2). TLD-handling and calibration for beta-dosimetry are described. Additional measurements for depth-dose and dose distribution around the tubes were done with GAFCHROMIC- films and compared to Monte-Carlo calculations with the MCNP4-code, yielding a half-value depth of 0.8 mm from the tube-surface. Manufacturing and delivery of the sources including leakage tests has been standardized, treatments (irradiation times <5min; irradiation length <30mm) are planned to start in spring `98. (authors) 1 refs., 5 figs.

  2. Endovascular gamma-irradiation for prevention of restenosis after angioplasty of femoropopliteal de-novo-stenoses. Long-term results of a feasibility study

    International Nuclear Information System (INIS)

    Krueger, K.; Zaehringer, M.; Schulte, O.; Lackner, K.; Bendel, M.; Bongartz, R.; Nolte, M.

    2002-01-01

    Objectives: To evaluate the performance and efficacy of endovascular irradiation after percutaneous transluminal angioplasty (PTA) of de-novo femoropopliteal stenoses in a pilot study. Methods: 6 patients received non-centered endovascular irradiation (12 Gray at surface of the vessel wall) immediately after angioplasty of de-novo femoropopliteal stenosis, 1 patient was given centered endovascular irradiation using 192-iridium (12 Gray at surface of the vessel wall) Centered irradiation was considered for two other patients. Duplex sonographies and interviews were performed the day before and after PTA and after 1, 3, 6, 9, 12, 18, 24 months up to 4 years. Intraarterial angiography was performed in symptomatic patients. Results: Non-centered endovascular irradiation was possible in all patiens without problems or complications. Centered irradiation was not possible in two patients with the cross-over approach. One thromboembolic complication occurred during centered irradiation. Both restenosis and new stenosis at the edge of irradiated distance occurred in 1/7 patiens. No other side effects were observed during follow-up. Conclusions: In our pilot study endovascular irradiation after angioplasty of de-novo femoropopliteal stenosis was possible with low rates of complications and restenosis and taking vessel anatomy into account. (orig.) [de

  3. Dose rate effect in food irradiation

    International Nuclear Information System (INIS)

    Singh, H.

    1991-08-01

    It has been suggested that the minor losses of nutrients associated with radiation processing may be further reduced by irradiating foods at the high dose rates generally associated with electron beams from accelerators, rather than at the low dose rates typical of gamma irradiation (e.g. 60 Co). This review briefly examines available comparative data on gamma and electron irradiation of foods to evaluate these suggestions. (137 refs., 27 tabs., 11 figs.)

  4. Modification of cell growth rate by irradiation

    International Nuclear Information System (INIS)

    Itoh, Hisao; Takemasa, Kazuhiko; Nishiguchi, Iku; Ka, Wei-Jei; Kutsuki, Shoji; Hashimoto, Shozo

    1993-01-01

    The effect of irradiation on the proliferation kinetics of the monolayer cells has been studied. Two human cell lines with different doubling times (HeLa-P and RMUG) and two clones that have the same radiosensitivity but different doubling times (HeLa-R and HeLa-S) were irradiated with a daily dose of 2 Gy for 6 days. The number of the clonogenic cells/dish was calculated by multiplying the number of total cell/dish by the survival fraction. In the rapidly growing cells (HeLa-P, HeLa-R), the number of the clonogenic cells was not decreased by the first two fractionated irradiations, but decreased thereafter at a similar rate as by single-dose fractionation, whereas the clonogenic cell number decreased from the first fractionated irradiation in the slowly growing cells (RMUG, HeLa-S). When the proliferation of clonogenic cell number increased along with a similar growth rates that was seen in all other types of cells. Further, no correlation was seen between the growth rates of cells without irradiation and cells that received irradiation. This latter result suggests that the slow growth rate of non-irradiated cells may not be the predictive factor of the tumor cure and the interruption of radiotherapy may reduce the beneficial effect of this treatment even in slow growing tumors. (author)

  5. Low mortality rates after endovascular aortic repair expand use to high-risk patients.

    Science.gov (United States)

    Adkar, Shaunak S; Turner, Megan C; Leraas, Harold J; Gilmore, Brian F; Nag, Uttara; Turley, Ryan S; Shortell, Cynthia K; Mureebe, Leila

    2018-02-01

    The 2010 endovascular aneurysm repair (EVAR) trial 2 (EVAR 2) reported that patients with comorbidity profiles rendering them unfit for open aneurysm repair who underwent EVAR did not experience a survival advantage compared with those who did not undergo intervention. These patients experienced a 30-day mortality of 7.3%, whereas reports from similar cohorts reported far lower mortality rates. The primary objective of our study was to compare the incidence of 30-day mortality in low- and high-risk patients undergoing EVAR in a contemporary data set, using patient risk stratification criteria from EVAR 2. Secondarily, we sought to identify risk factors associated with a disproportionate contribution to 30-day mortality risk. Data were obtained from the 2005 to 2013 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Participant Use Data Files (N = 24,813). Patients were included in the high-risk cohort with the presence of renal, respiratory, or cardiac preoperative criteria alone or in combination. Renal impairment criteria were defined as dialysis and creatinine concentration >2.26 mg/dL. Respiratory impairment criteria included history of chronic obstructive pulmonary disease and preoperative ventilator support. Cardiac impairment criteria included history of myocardial infarction, congestive heart failure, angina, and prior coronary intervention. Patient and procedural characteristics and 30-day postoperative outcomes were compared using Pearson χ 2 tests for categorical variables and Wilcoxon rank sum tests for continuous variables. Among 24,813 patients undergoing EVAR, 12,043 (48%) patients were characterized as high risk (at least one impairment criterion); 12,770 (52%) patients were stratified as low risk. The 30-day mortality rate was 1.9% in the high-risk cohort compared with the 7.3% reported by EVAR 2, and it was higher in the high-risk cohort compared with the low-risk cohort (1.9% vs 0.9%; P < .001). Whereas the

  6. Low dose irradiation reduces cancer mortality rates

    International Nuclear Information System (INIS)

    Luckey, T.D.

    2000-01-01

    Low doses of ionizing radiation stimulate development, growth, memory, sensual acuity, fecundity, and immunity (Luckey, T.D., ''Radiation Hormesis'', CRC Press, 1991). Increased immune competence reduces cancer mortality rates and provides increased average lifespan in animals. Decreased cancer mortality rates in atom bomb victims who received low dose irradiation makes it desirable to examine populations exposed to low dose irradiation. Studies with over 300,000 workers and 7 million person-years provide a valid comparison of radiation exposed and control unclear workers (Luckey, T.D., Nurture with Ionizing Radiation, Nutrition and Cancer, 34:1-11, 1999). Careful selection of controls eliminated any ''healthy worker effect''. The person-year corrected average indicated the cancer mortality rate of exposed workers was only 51% that of control workers. Lung cancer mortality rates showed a highly significant negative correlation with radon concentrations in 272,000 U.S. homes (Cohen, B.L., Health Physics 68:157-174, 1995). In contrast, radon concentrations showed no effect on lung cancer rates in miners from different countries (Lubin, J.H. Am. J. Epidemiology 140:323-332, 1994). This provides evidence that excessive lung cancer in miners is caused by particulates (the major factor) or toxic gases. The relative risk for cancer mortality was 3.7% in 10,000 Taiwanese exposed to low level of radiation from 60 Co in their steel supported homes (Luan, Y.C. et al., Am. Nuclear Soc. Trans. Boston, 1999). This remarkable finding needs further study. A major mechanism for reduced cancer mortality rates is increased immune competence; this includes both cell and humoral components. Low dose irradiation increases circulating lymphocytes. Macrophage and ''natural killer'' cells can destroy altered (cancer) cells before the mass becomes too large. Low dose irradiation also kills suppressor T-cells; this allows helper T-cells to activate killer cells and antibody producing cells

  7. Radiobiological aspects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation

    International Nuclear Information System (INIS)

    Turesson, I.

    1990-01-01

    The biological effects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation in interstitial and intracavitary radiotherapy and total body irradiation are discussed in terms of dose-rate fractionation sensitivity for various tissues. A scaling between dose-rate and fraction size was established for acute and late normal-tissue effects which can serve as a guideline for local treatment in the range of dose rates between 0.02 and 0.005 Gy/min and fraction sizes between 8.5 and 2.5 Gy. This is valid provided cell-cycle progression and proliferation can be ignored. Assuming that the acute and late tissue responses are characterized by α/β values of about 10 and 3 Gy and a mono-exponential repair half-time of about 3 h, the same total doses given with either of the two methods are approximately equivalent. The equivalence for acute and late non-hemopoietic normal tissue damage is 0.02 Gy/min and 8.5 Gy per fraction; 0.01 Gy/min and 5.5 Gy per fraction; and 0.005 Gy/min and 2.5Gy per fraction. A very low dose rate, below 0.005 Gy/min, is thus necessary to simulate high dose-rate radiotherapy with fraction sizes of about 2Gy. The scaling factor is, however, dependent on the repair half-time of the tissue. A review of published data on dose-rate effects for normal tissue response showed a significantly stronger dose-rate dependence for late than for acute effects below 0.02 Gy/min. There was no significant difference in dose-rate dependence between various acute non-hemopoietic effects or between various late effects. The consistent dose-rate dependence, which justifies the use of a general scaling factor between fraction size and dose rate, contrasts with the wide range of values for repair half-time calculated for various normal-tissue effects. This indicates that the model currently used for repair kinetics is not satisfactory. There are also few experimental data in the clinical dose-rate range, below 0.02 Gy/min. It is therefore

  8. Dose rate distribution for products irradiated in a semi-industrial irradiation plant. 1st stage

    International Nuclear Information System (INIS)

    Mangussi, J.

    2005-01-01

    The model of the bulk product absorbed dose rate distribution in a semi industrial irradiation plant is presented. In this plant the products are subject to a dynamic irradiation process: single-plaque, single-direction, four-passes. The additional two passes, also one on each side of the plaque, serve to minimize the lateral dose variation as well as the depth-dose non-uniformity. The first stage of this model takes only into account the direct absorbed dose rate; the model outputs are the depth-dose distribution and the lateral-dose distribution. The calculated absorbed dose in the bulk product and its uniformity-ratio after the dynamic irradiation process for different products is compared. The model results are in good agreement with the experimental measurements in a bulk of irradiated product; and the air absorbed dose rate in the irradiation chamber behind the product subject to the dynamic irradiation process. (author) [es

  9. The reaction rates of electrons with native and irradiated ribonuclease

    International Nuclear Information System (INIS)

    Schuessler, H.; Ebert, M.; Davies, J.V.

    1977-01-01

    The rate of reaction of hydrated electrons with proteins depends, amongst other things, on the conformational structure of the protein, and irradiation itself causes conformational changes in proteins. A study has been made of variations in the reaction rates of hydrated electrons with RNase pre-irradiated by the Linac or by a 60 Co γ-source. The reaction rate constants varied with the pre-irradiation dose, the concentration of phosphate buffer, the enzyme concentration and also the presence of 10 -2 M ethanol. These variations serve to emphasize the importance of the tertiary structure of biological molecules in irradiation processes and have significant implications in the mathematical analysis of the inactivation of enzymes in steady-state irradiation processes. (U.K.)

  10. Dose rate modelled for the outdoors of a gamma irradiation

    International Nuclear Information System (INIS)

    Mangussi, J

    2012-01-01

    A model for the absorbed dose rate calculation on the surroundings of a gamma irradiation plant is developed. In such plants, a part of the radiation emitted upwards reach's the outdoors. The Compton scatterings on the wall of the exhausting pipes through de plant roof and on the outdoors air are modelled. The absorbed dose rate generated by the scattered radiation as far as 200 m is calculated. The results of the models, to be used for the irradiation plant design and for the environmental studies, are showed on graphics (author)

  11. Comparison of initial damage rates using neutron and electron irradiations

    International Nuclear Information System (INIS)

    Goldstone, J.A.R.

    1978-08-01

    The purpose of this experiment was twofold: (1) The number of interstitials that pin dislocations was studied as a function of neutron energy. (2) By comparison with electron irradiations on the sample, a correlation between the predicted and measured numbers of defects was found. All irradiations were performed on the same high purity copper sample. The sample was machined in the form of a cantilever beam with a flexural resonant frequency of 770 Hz. Changes in Young's modulus at constant strain amplitude were monitored continuously through changes in the resonant frequency of the sample. These changes in the modulus can be related to the number of pinning points added to dislocation lines, which are in turn related to the number of free interstitials produced. Neutron energy dependence experiments were done from 2 to 24 MeV on the copper sample and at 14 MeV on a gold sample. By equating pinning rates from electron and neutron irradiations and using the free interstitial production rate obtained from electron irradiations, an estimate of the free interstitial production cross section for neutrons of 2 to 24 MeV was made

  12. Endovascular Management of Acute Limb Ischemia.

    LENUS (Irish Health Repository)

    Hynes, Brian G

    2011-09-14

    Despite major advances in pharmacologic and endovascular therapies, acute limb ischemia (ALI) continues to result in significant morbidity and mortality. The incidence of ALI may be as high as 13-17 cases per 100,000 people per year, with mortality rates approaching 18% in some series. This review will address the contemporary endovascular management of ALI encompassing pharmacologic and percutaneous interventional treatment strategies.

  13. Response of human fibroblasts to low dose rate gamma irradiation

    International Nuclear Information System (INIS)

    Dritschilo, A.; Brennan, T.; Weichselbaum, R.R.; Mossman, K.L.

    1984-01-01

    Cells from 11 human strains, including fibroblasts from patients with the genetic diseases of ataxia telangiectasia (AT), xeroderma pigmentosum (XP), and Fanconi's anemia (FA), were exposed to γ radiation at high (1.6-2.2 Gy/min) and at low (0.03-0.07 Gy/min) dose rates. Survival curves reveal an increase inthe terminal slope (D 0 ) when cells are irradiated at low dose rates compared to high dose rates. This was true for all cell lines tested, although the AT, FA, and XP cells are reported or postulated to have radiation repair deficiencies. From the response of these cells, it is apparent that radiation sensitivities differ; however, at low dose rate, all tested human cells are able to repair injury

  14. Defect creation rates in CdTe irradiated by electrons

    International Nuclear Information System (INIS)

    Caillot, M.

    1978-01-01

    Up to now, the defect creation rates in CdTe irradiated by electrons were unknown. They have been calculated for different electron kinetic energies. As the samples studied are thick, the energy loss when the electrons penetrate the material has been taken into account. The cross-sections of Cd and Te displacements vs the depth of electron penetration were determined for different electron kinetic energies, and the defect creation rates obtained for each sublattice. These creation rates have been compared with those deduced from experiments and it was found that the experimental creation rates were lower than the calculated ones. This discrepancy can be explained in terms of creation of neutral Frenkel pairs. (Auth.)

  15. Effect of neutron irradiation on hatching rate of eggs and growth rate of chicken

    International Nuclear Information System (INIS)

    Liu Yubin; Zhao Jide; Liu Shengdian; Xy Xiuwei

    1995-01-01

    It was proved through 3 years of experiments and productions that after the eggs of AA meat chickens being irradiated by 14 MeV fast neutron, the hatching rate and the survival rate as well the weight of commercial chickens increased greatly. In addition it is found that the optimum neutron fluence for hatching and growth rate is 6.2 x 10 5 n·cm -2

  16. Vascular training and endovascular practice in Europe

    DEFF Research Database (Denmark)

    Liapis, C.D.; Avgerinos, E.D.; Sillesen, H.

    2009-01-01

    specialties was distributed to a VS educator within 14 European countries. European Vascular and Endovascular Monitor (EVEM) data also were processed to correlate endovascular practice with training models. RESULTS: Fourteen questionnaires were gathered. Vascular training in Europe appears in 3 models: 1....... Mono-specialty (independence): 7 countries, 2. Subspecialty: 5 countries, 3. An existing specialty within general surgery: 2 countries. Independent compared to non-independent certification shortens overall training length (5.9 vs 7.9 years, p=0.006), while increasing overall training devoted......% respectively. Countries with independent vascular certification, despite their lower average endovascular index (procedures per 100,000 population), reported a higher growth rate of aortic endovascular procedures (VS independent 132% vs VS non-independent 87%), within a four-year period (2003-2007). Peripheral...

  17. Dissolution rate effect upon lyolumenescence of irradiated potassium chloride

    International Nuclear Information System (INIS)

    Leshchinskij, B.L.; Dzelme, Yu.R.; Tiliks, Yu.E.; Bugaenko, L.T.

    1985-01-01

    The paper is aimed at studying dissolution rate effect and concentration of electron acceptor upon lyoluminescence (LL) that occurs during dissolution of solids with radiation defects. For investigation gamma-irradiated potassium chloride monocrystalline disks were used. As a solvent 3x10sup(-6) M solution of C(RH) hodamine in 2.7 KCl aqueous solution is used. It is shown that LL occurs as a result of recombination of radiation defects with the solution and between themselves in two different regions of subsurface layer of the solid. Investigated dependences of LL intensty on dissolution rate are the efficient method of studying the structure of solids-aqueous solution interface and LL mechanism

  18. Evaluation of strain-rate sensitivity of ion-irradiated austenitic steel using strain-rate jump nanoindentation tests

    Energy Technology Data Exchange (ETDEWEB)

    Kasada, Ryuta, E-mail: r-kasada@iae.kyoto-u.ac.jp [Institute of Advanced Energy, Kyoto University Gokasho, Uji 611-0011, Kyoto (Japan); Konishi, Satoshi [Institute of Advanced Energy, Kyoto University Gokasho, Uji 611-0011, Kyoto (Japan); Hamaguchi, Dai; Ando, Masami; Tanigawa, Hiroyasu [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan)

    2016-11-01

    Highlights: • We examined strain-rate jump nanoindentation on ion-irradiated stainless steel. • We observed irradiation hardening of the ion-irradiated stainless steel. • We found that strain-rate sensitivity parameter was slightly decreased after the ion-irradiation. - Abstract: The present study investigated strain-rate sensitivity (SRS) of a single crystal Fe–15Cr–20Ni austenitic steel before and after 10.5 MeV Fe{sup 3+} ion-irradiation up to 10 dpa at 300 °C using a strain-rate jump (SRJ) nanoindentation test. It was found that the SRJ nanoindentation test is suitable for evaluating the SRS at strain-rates from 0.001 to 0.2 s{sup −1}. Indentation size effect was observed for depth dependence of nanoindentation hardness but not the SRS. The ion-irradiation increased the hardness at the shallow depth region but decreased the SRS slightly.

  19. Evolution of patency rates of self-expandable bare metal stents for endovascular treatment of femoro-popliteal arterial occlusive disease: Does stent design matter?

    Science.gov (United States)

    Treitl, Karla Maria; Woerner, Benedikt; Schinner, Regina; Czihal, Michael; Notohamiprodjo, Susan; Hoffmann, Ulrich; Treitl, Marcus

    2017-09-01

    To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs. Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification. Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P stent and the highest TLR_12M for the CC stent. The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months. • Results of femoro-popliteal stenting are still unsatisfactory. • Comparative studies for currently available different Nitinol stent-designs are lacking. • This is a first comparative study on long-term patency of different Nitinol stent-designs. • Interwoven stent-design leads to improved long-term patency. • Interwoven stent-design leads to lower TLR than other stent-designs.

  20. Respiration rate of gamma irradiation carnation cut flowers

    International Nuclear Information System (INIS)

    Kikuchi, Olivia Kimiko; Wiendl, Frederico Maximiliano; Todoriki, Setsuko; Nakahara, Kazuhiko; Haysahi, Toru

    1996-01-01

    The present paper presents the CO 2 production of the carnation cut flowers gamma-irradiated with a single dose of 750 Gy. The cut flowers were soaked in preservative solutions, containing germicides or germicides plus 2% sucrose. The irradiation did not change the CO 2 production and did not cause any visible flower damage. The sucrose exogenous supply extended the vase-life of both irradiated and non-irradiated carnations. These results indicated that Nora carnation cut flower can be irradiated with 750 Gy without commercial viability loss and that it is possible to use the radiation to disinfect this fresh product. (author)

  1. Endovascular Management of Acute Bleeding Arterioenteric Fistulas

    International Nuclear Information System (INIS)

    Leonhardt, Henrik; Mellander, Stefan; Snygg, Johan; Loenn, Lars

    2008-01-01

    The objective of this study was to review the outcome of endovascular transcatheter repair of emergent arterioenteric fistulas. Cases of abdominal arterioenteric fistulas (defined as a fistula between a major artery and the small intestine or colon, thus not the esophagus or stomach), diagnosed over the 3-year period between December 2002 and December 2005 at our institution, were retrospectively reviewed. Five patients with severe enteric bleeding underwent angiography and endovascular repair. Four presented primary arterioenteric fistulas, and one presented a secondary aortoenteric fistula. All had massive persistent bleeding with hypotension despite volume substitution and transfusion by the time of endovascular management. Outcome after treatment of these patients was investigated for major procedure-related complications, recurrence, reintervention, morbidity, and mortality. Mean follow-up time was 3 months (range, 1-6 months). All massive bleeding was controlled by occlusive balloon catheters. Four fistulas were successfully sealed with stent-grafts, resulting in a technical success rate of 80%. One patient was circulatory stabilized by endovascular management but needed immediate further open surgery. There were no procedure-related major complications. Mean hospital stay after the initial endovascular intervention was 19 days. Rebleeding occurred in four patients (80%) after a free interval of 2 weeks or longer. During the follow-up period three patients needed reintervention. The in-hospital mortality was 20% and the 30-day mortality was 40%. The midterm outcome was poor, due to comorbidities or rebleeding, with a mortality of 80% within 6 months. In conclusion, endovascular repair is an efficient and safe method to stabilize patients with life-threatening bleeding arterioenteric fistulas in the emergent episode. However, in this group of patients with severe comorbidities, the risk of rebleeding is high and further intervention must be considered

  2. Endovascular management of acute bleeding arterioenteric fistulas

    DEFF Research Database (Denmark)

    Leonhardt, H.; Mellander, S.; Snygg, J.

    2008-01-01

    follow-up time was 3 months (range, 1-6 months). All massive bleeding was controlled by occlusive balloon catheters. Four fistulas were successfully sealed with stent-grafts, resulting in a technical success rate of 80%. One patient was circulatory stabilized by endovascular management but needed....... All had massive persistent bleeding with hypotension despite volume substitution and transfusion by the time of endovascular management. Outcome after treatment of these patients was investigated for major procedure-related complications, recurrence, reintervention, morbidity, and mortality. Mean...... arterioenteric fistulas in the emergent episode. However, in this group of patients with severe comorbidities, the risk of rebleeding is high and further intervention must be considered. Patients with cancer may only need treatment for the acute bleeding episode, and an endovascular approach has the advantage...

  3. Effect of the irradiation of bacteria upon their survival rate during conventional methods of meat preservation

    International Nuclear Information System (INIS)

    Szczawinska, M.

    1981-01-01

    The purpose of this paper is to define the effect of irradiation upon the survival rate of non-sporing bacteria (Staphylococcus aureus, Salmonella typhimurium, Escherichia coli, Pseudomonas fluorescens) during basic methods of meat preservation. The bacteria were irradiated in broth by X-rays at a dose that destroyed about 90% of the bacteria (D 10 ). The survival rate of unirradiated and irradiated bacteria during cooling and freezing, in solutions of sodium chloride, nitrates and liquid smoke, was defined. The number of microorganisms was determined directly after irradiation as well as 1, 3, 7, 14, 21 and 28 days after irradiation. The effect of irradiation upon heat resistance of the examined species of bacteria was also defined. The microorganisms were heated in broth, at 70 0 C for 1, 2 and 5 minutes. The obtained results were subjected to statistical analysis. On the basis of the research results, a faster dying rate of irradiated populations of S. aureus and E. coli during any type of preservation treatment, the lack of any reaction to irradiation regarding the survival rate of S. typhimurium, and the lack of any effect of irradiation upon the rate of deterioration of P. fluorescens during freezing and storage in a solution with 10% addition of NaCI, were observed. On the other hand, a pronounced effect of irradiation upon the lowering of the heat resistance of the bacteria, as well as delayed growth in other variants of the experiment, was determined. (author)

  4. Acute vasculitis after endovascular brachytherapy

    International Nuclear Information System (INIS)

    Fajardo L-G, Luis F.; Prionas, Stavros D.; Kaluza, Grzegorz L.; Raizner, Albert E.

    2002-01-01

    Purpose: Angioplasty effectively relieves coronary artery stenosis but is often followed by restenosis. Endovascular radiation (β or γ) at the time of angioplasty prevents restenosis in a large proportion of vessels in swine (short term) and humans (short and long term). Little information is available about the effects of this radiation exposure beyond the wall of the coronary arteries. Methods and Materials: Samples were obtained from 76 minipigs in the course of several experiments designed to evaluate endovascular brachytherapy: 76 of 114 coronary arteries and 6 of 12 iliac arteries were exposed to endovascular radiation from 32 P sources (35 Gy at 0.5 mm from the intima). Two-thirds of the vessels had angioplasty or stenting. The vessels were systematically examined either at 28 days or at 6 months after radiation. Results: We found an unexpected lesion: acute necrotizing vasculitis in arterioles located ≤2.05 mm from the target artery. It was characterized by fibrinoid necrosis of the wall, often associated with lymphocytic exudates or thrombosis. Based on the review of perpendicular sections of tissue samples, the arterioles had received between 6 and 40 Gy. This arteriolar vasculitis occurred at 28 days in samples from 51% of irradiated coronary arteries and 100% of irradiated iliac arteries. By 6 months, the incidence of acute vasculitis decreased to 24% around the coronary arteries. However, at that time, healing vasculitis was evident, often with luminal narrowing, in 46% of samples. Vasculitis was not seen in any of 44 samples from unirradiated vessels (0%) and had no relation to angioplasty, stenting, or their sequelae. This radiation-associated vasculitis in the swine resembles the localized lymphocytic vasculitis that we have reported in tissues of humans exposed to external radiation. On the other hand, it is quite different from the various types of systemic vasculitis that occur in nonirradiated humans. Conclusion: Endoarterial brachytherapy

  5. Optimal rate of irradiation of the organizms in cow's milk

    International Nuclear Information System (INIS)

    Filipov, Zh.

    1981-01-01

    Results showed that with increasing the time of ultra violet treatment the microbial pollution of milk dropped. With the irradiation method used by the authors best bactericidal effects were obtained at 60 min treatment. (author)

  6. Post irradiation examinations of uranium-plutonium mixed carbide fuels irradiated at low linear power rate

    International Nuclear Information System (INIS)

    Maeda, Atsushi; Sasayama, Tatsuo; Iwai, Takashi; Aizawa, Sakuei; Ohwada, Isao; Aizawa, Masao; Ohmichi, Toshihiko; Handa, Muneo

    1988-11-01

    Two pins containing uranium-plutonium carbide fuels which are different in stoichiometry, i.e. (U,Pu)C 1.0 and (U,Pu)C 1.1 , were constructed into a capsule, ICF-37H, and were irradiated in JRR-2 up to 1.0 at % burnup at the linear heat rate of 420 W/cm. After being cooled for about one year, the irradiated capsule was transferred to the Reactor Fuel Examination Facility where the non-destructive examinations of the fuel pins in the β-γ cells and the destructive ones in two α-γ inert gas atmosphere cells were carried out. The release rates of fission gas were low enough, 0.44 % from (U,Pu)C 1.0 fuel pin and 0.09% from (U,Pu)C 1.1 fuel pin, which is reasonable because of the low central temperature of fuel pellets, about 1000 deg C and is estimated that the release is mainly governed by recoil and knock-out mechanisms. Volume swelling of the fuels was observed to be in the range of 1.3 ∼ 1.6 % for carbide fuels below 1000 deg C. Respective open porosities of (U,Pu)C 1.0 and (U,Pu)C 1.1 fuel were 1.3 % and 0.45 %, being in accordance with the release behavior of fission gas. Metallographic observation of the radial sections of pellets showed the increase of pore size and crystal grain size in the center and middle region of (U,Pu)C 1.0 pellets. The chemical interaction between fuel pellets and claddings in the carbide fuels is the penetration of carbon in the fuels to stainless steel tubes. The depth of corrosion layer in inner sides of cladding tubes ranged 10 ∼ 15 μm in the (U,Pu)C 1.0 fuel and 15 #approx #25 μm in the (U,Pu)C 1.1 fuel, which is correlative with the carbon potential of fuels posibly affecting the amount of carbon penetration. (author)

  7. Physical aspects of endovascular brachytherapy

    International Nuclear Information System (INIS)

    Kirisits, C.

    2001-11-01

    Restenosis is severely limiting the outcome of vascular interventions. In several clinical trials endovascular brachytherapy has shown to reduce the restenosis rate. Local radiotherapy to the injured vessel wall is a promising new type of treatment in order to inhibit a complex wound healing process resulting in cell proliferation and re-obstruction of the treated vessel. Treatment planning has to be based on the dose distribution in the vicinity of the sources used. Source strength was determined in terms of air kerma rate for gamma nuclides (Iridium-192) and absorbed dose to water at reference distance of 2 mm for beta nuclides (Strontium-90/Yttrium-90, Phosphor-32), respectively. Radial dose profiles and the Reference Isodose Length (RIL) were determined using the EGSnrc code and GafChromic film. Good agreement was found between both methods. In order to treat the entire clinical target length, the (RIL) is an essential value during treatment planning. Examples are described for different levels of treatment planing including recommendations for optimal choice and positioning of the radioactive devices inside the artery. IVUS based treatment planning is illustrated with superposition of isodoses on cross-sectional images. A calculation model for radioactive stents is presented in order to determine dose volume histograms in a retrospective analysis. Radiation protection issues for endovascular brachytherapy are discussed in detail. Personal dose for the involved personnel is estimated based on calculations and measurements. Beta ray dosimetry is performed with suitable detectors. In order to estimate the exposure to the patient the dose to organs at risk is calculated and compared to the dose from angiography. There is an additional radiation exposure to patients and personnel caused by endovascular brachytherapy, but the values are much smaller than those caused by diagnostic angiography. (author)

  8. An algorithm to evaluate solar irradiance and effective dose rates using spectral UV irradiance at four selected wavelengths

    International Nuclear Information System (INIS)

    Anav, A.; Rafanelli, C.; Di Menno, I.; Di Menno, M.

    2004-01-01

    The paper shows a semi-analytical method for environmental and dosimetric applications to evaluate, in clear sky conditions, the solar irradiance and the effective dose rates for some action spectra using only four spectral irradiance values at selected wavelengths in the UV-B and UV-A regions (305, 320, 340 and 380 nm). The method, named WL4UV, is based on the reconstruction of an approximated spectral irradiance that can be integrated, to obtain the solar irradiance, or convoluted with an action spectrum to obtain an effective dose rate. The parameters required in the algorithm are deduced from archived solar spectral irradiance data. This database contains measurements carried out by some Brewer spectrophotometers located in various geographical positions, at similar altitudes, with very different environmental characteristics: Rome (Italy), Ny Aalesund (Svalbard Islands (Norway)) and Ushuaia (Tierra del Fuego (Argentina)). To evaluate the precision of the method, a double test was performed with data not used in developing the model. Archived Brewer measurement data, in clear sky conditions, from Rome and from the National Science Foundation UV data set in San Diego (CA, USA) and Ushuaia, where SUV 100 spectro-radiometers operate, were drawn randomly. The comparison of measured and computed irradiance has a relative deviation of about ±2%. The effective dose rates for action spectra of Erythema, DNA and non-Melanoma skin cancer have a relative deviation of less than ∼20% for solar zenith angles <50 deg.. (authors)

  9. Effect of Gamma Irradiation on Water Uptake Rate and Gelatinization of Brown Rice

    International Nuclear Information System (INIS)

    Shu, C.S.; Lee, J.W.; Lee, Y.S.; Byun, M.W.

    2004-01-01

    Effects of gamma irradiation on brown rice quality were evaluated. Brown rice was irradiated at absorbed dose of 1, 3 or 5 kGy, and ground. Water uptake, pasting properties, and physicochemical characteristics of flour samples were tested. Water uptake rates of irradiated samples were higher than that of control, and were dose-dependent. Hydration capacity decreased in sample irradiated at 5 kGy due to leaching out of soluble compounds, whereas no differences were observed among other irradiated samples and control

  10. Comparison of radiosensitization by 41 deg. C hyperthermia during low dose rate irradiation and during pulsed simulated low dose rate irradiation in human glioma cells

    International Nuclear Information System (INIS)

    Raaphorst, G. Peter; Ng, Cheng E.; Shahine, Bilal

    1999-01-01

    Purpose: Long duration mild hyperthermia has been shown to be an effective radiosensitizer when given concurrently with low dose rate irradiation. Pulsed simulated low dose rate (PSLDR) is now being used clinically, and we have set out to determine whether concurrent mild hyperthermia can be an effective radiosensitizer for the PSLDR protocol. Materials and Methods: Human glioma cells (U-87MG) were grown to plateau phase and treated in plateau phase in order to minimize cell cycle redistribution during protracted treatments. Low dose rate (LDR) irradiation and 41 deg. C hyperthermia were delivered by having a radium irradiator inside a temperature-controlled incubator. PSLDR was given using a 150 kVp X-ray unit and maintaining the cells at 41 deg. C between irradiations. The duration of irradiation and concurrent heating depended on total dose and extended up to 48 h. Results: When 41 deg. C hyperthermia was given currently with LDR or PSLDR, the thermal enhancement ratios (TER) were about the same if the average dose rate for PSLDR was the same as for LDR. At higher average dose rates for PSLDR the TERs became less. Conclusions: Our data show that concurrent mild hyperthermia can be an effective sensitizer for PSLDR. This sensitization can be as effective as for LDR if the same average dose rate is used and the TER increases with decreasing dose rate. Thus mild hyperthermia combined with PSLDR may be an effective clinical protocol

  11. Endovascular repair of blunt popliteal arterial injuries

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Shan; Zhang, Xiquan; Chen, Zhong; Zhu, Wei; Pan, Xiaolin [Dept. of nterventional Vascular, The 148th Hospital of Chinese People' s Liberation Army, Zibo (China); Dong, Peng; Sun, Yequan [Dept. of Medical Imaging, Weifang Medical University, Weifang (China); Qi, Deming [Dept. of Medical Imaging, Qilu Medical University, Zibo (China)

    2016-09-15

    To evaluate the feasibility and effectiveness of endovascular repair for blunt popliteal arterial injuries. A retrospective analysis of seven patients with clinical suspicion of popliteal arterial injuries that were confirmed by arteriography was performed from September 2009 to July 2014. Clinical data included demographics, mechanism of injury, type of injury, location of injury, concomitant injuries, time of endovascular procedures, time interval from trauma to blood flow restoration, instrument utilized, and follow-up. All patients were male (mean age of 35.9 ± 10.3 years). The type of lesion involved intimal injury (n = 1), partial transection (n = 2), complete transection (n = 2), arteriovenous fistula (n = 1), and pseudoaneurysm (n = 1). All patients underwent endovascular repair of blunt popliteal arterial injuries. Technical success rate was 100%. Intimal injury was treated with a bare-metal stent. Pseudoaneurysm and popliteal artery transections were treated with bare-metal stents. Arteriovenous fistula was treated with bare-metal stent and coils. No perioperative death and procedure-related complication occurred. The average follow-up was 20.9 ± 2.3 months (range 18–24 months). One patient underwent intra-arterial thrombolysis due to stent thrombosis at 18 months after the procedure. All limbs were salvaged. Stent migration, deformation, or fracture was not found during the follow-up. Endovascular repair seems to be a viable approach for patients with blunt popliteal arterial injuries, especially on an emergency basis. Endovascular repair may be effective in the short-term. Further studies are required to evaluate the long-term efficacy of endovascular repair.

  12. The effect of texture, heat treatment and elongation rate on stress corrosion cracking in irradiated zircaloy

    International Nuclear Information System (INIS)

    Pettersson, K.; Stany, W.; Hellstrand, E.

    1979-03-01

    Irradiated zircaloy samples with different textures and heat treatments have been tested concerning stress corrosion. Irradiated samples of Zr-1Nb, pure Zr and beta quenched zircaloy have also been investigated. Stress-relieve annealled zircaloy is even after irradiation more sensitive to stress corrosion than recrystallized zircaloy. Zr-1Nb and beta quenched zircaloy are much more sinsitive to stress corrosion than the samples with different textures. As a rule irradiated zircaloy is sensitive to stress corrosion at stresses far below the yield point. The breaking stress decreases with the elongation rate. The extension of cracks is much faster in irradiated zircaloy than in unirradiated zircaloy. There is no simple failure criterium for irradiated zircaloy. However for a certain stress and a certain elongation rate the probability for a failure before this stress is reached with a constant elongation rate can be given. (E.R.)

  13. Effects of low-dose rate irradiation on two types of type II diabetes model mice

    International Nuclear Information System (INIS)

    Nomura, Takaji; Sakai, Kazuo

    2004-01-01

    The effects of low-dose rate gamma-irradiation were investigated in two mouse strains - C57BL/KsJ-db/db (db mouse) and AKITA (AKITA mouse)-for type II diabetes mellitus. Both strains develop the developed type II diabetes by about 8 weeks of age due to dysfunction of the insulin/insulin receptor. The db Mouse' shows obese and exhibits hyperinsulinism, and the onset of Type II diabetes like resembles that for Westerners. On the other hand, the AKITA mouse has exhibits disordered insulin secretion, and the diabetes such as resembles that of Asians. Ten-week old female mice, in groups of 8 or 12, were irradiated at 0.65 mGy/hr in the low-dose rate irradiation facility in the Low Dose Radiation Research Center. The level of urine glucose was measured with test slips. The urine glucose levels of all of the mice were highly elevated the beginning of the irradiation. In the irradiated group of db mice, three mice showed decrease in glucose level compare to the level of non-irradiated diabetes mice after 35, 52 or 80 weeks of irradiation. All had maintained a normal level thereafter. No such improvement in diabetes was ever observed in the 12 mice of in the non-irradiated control group. The AKITA mice, however, did not decrease the glucose level regardless of the irradiation. Both the db mice and AKITA mice had their lives prolonged their life by the irradiation. The survival rate of db mice at the age of 90 weeks was 75% in the irradiated group, but 50% in the non-irradiated group. The average life span was 104 weeks in the irradiated group and 87 weeks in the control group. Furthermore, a marked difference was furthermore observed in the appearance of the coat hair, skin, and tail; appearances were well preserved in the irradiated group. The average life span in the irradiated AKITA mice was also longer than that for the non-irradiated mice, 51 weeks and 41 weeks in the irradiated and non-irradiated group respectively. These results suggest that the low-dose irradiation

  14. Application of accelerated evaluation method of alteration temperature and constant dose rate irradiation on bipolar linear regulator LM317

    International Nuclear Information System (INIS)

    Deng Wei; Wu Xue; Wang Xin; Zhang Jinxin; Zhang Xiaofu; Zheng Qiwen; Ma Wuying; Lu Wu; Guo Qi; He Chengfa

    2014-01-01

    With different irradiation methods including high dose rate irradiation, low dose rate irradiation, alteration temperature and constant dose rate irradiation, and US military standard constant high temperature and constant dose rate irradiation, the ionizing radiation responses of bipolar linear regulator LM317 from three different companies were investigated under the operating and zero biases. The results show that compared with constant high temperature and constant dose rate irradiation method, the alteration temperature and constant dose rate irradiation method can not only very rapidly and accurately evaluate the dose rate effect of three bipolar linear regulators, but also well simulate the damage of low dose rate irradiation. Experiment results make the alteration temperature and constant dose rate irradiation method successfully apply to bipolar linear regulator. (authors)

  15. ATM phosphorylation in HepG2 cells following continuous low dose-rate irradiation

    International Nuclear Information System (INIS)

    Mei Quelin; Du Duanming; Chen Zaizhong; Liu Pengcheng; Yang Jianyong; Li Yanhao

    2008-01-01

    Objective: To investigate the change of ATM phosphorylation in HepG2 cells following a continuous low dose-rate irradiation. Methods: Cells were persistently exposed to low dose-rate (8.28 cGy/h) irradiation. Indirect immunofluorescence and Western blot were used to detect the expression of ATM phosphorylated proteins. Colony forming assay was used to observe the effect of a low dose-rate irradiation on HepG2 cell survival. Results: After 30 min of low dose-rate irradiation, the phosphorylation of ATM occurred. After 6 h persistent irradiation, the expression of ATM phosphorylated protein reached the peak value, then gradually decreased. After ATM phosphorylation was inhibited with Wortmannin, the surviving fraction of HepG2 cells was lower than that of the irradiation alone group at each time point (P<0.05). Conclusions: Continuous low dose-rate irradiation attenuated ATM phosphorylation, suggesting that continuous low dose-rate irradiation has a potential effect for increasing the radiosensitivity of HepG2 cells. (authors)

  16. High dose rate intracavitary afterloading irradiation in malignant inoperable obturation of bile ducts

    Energy Technology Data Exchange (ETDEWEB)

    Itami, J.; Saegusa, K.; Mamiya, T.; Miyoshi, T.; Arimizu, N.; Tsuchiya, Y.; Ohto, M.

    1986-02-01

    After decompression of the bile duct with PTCD, seven patients with carcinomas of the bile ducts were submitted to an intracavitary Ir-afterloading irradiation performed according to the high-dose-rate method with a Buchler device. Most of the patients were irradiated with 30 Gy in two fractions. Five patients were also exposed to percutaneous radiation with 40 to 50 Gy. Local control was achieved in six patients. One patient developed a locoregional recurrence which was possibly due to a so-called 'geographic miss'. In one patient a benign fibrotic stenosis of the bile duct was found at the site of most intensive irradiation. Intracavitary irradiation is very important in the treatment of malignant of bile ducts. However, there is an urgent need of research with regard to the combined method with percutaneous irradiation and to the optimum fractionation of intracavitary high dose rate irradiation.

  17. Dose and dose rate effects on coherent-to-incoherent transition of precipitates upon irradiation

    Institute of Scientific and Technical Information of China (English)

    LI Zhengchao

    2006-01-01

    A typical precipitation hardened alloy, Cu-Co dilute alloy was selected to study the precipitation behavior and irradiation effect on precipitates. It is found that the principal effect of ion irradiation on the coherent precipitates is loss of coherency, and TEM cross-section observations show that the fraction of the incoherent precipitates is dependent on dose but not on dose rate during heavy ion irradiation.

  18. Manejo endovascular de la aorta torácica Endovascular treatment of thoracic aorta

    Directory of Open Access Journals (Sweden)

    Juan G Barrera

    2006-10-01

    Full Text Available En comparación con el tratamiento convencional, la terapia endovascular en aneurisma de aorta torácica, presenta los mejores resultados, por lo que se convierte en el tratamiento de elección para la patología de aorta torácica descendente endovascular, por su baja morbimortalidad perioperatoria. El tratamiento quirúrgico por vía retroperitoneal y/o endovascular para aneurisma de aorta abdominal infrarrenal, resulta ser especialmente seguro en pacientes octogenarios o con alta morbilidad. Esta cohorte institucional presenta resultados perioperatorios y en el seguimiento, similares a los reportados en la literatura mundial.Compared with the conventional treatment, endovascular therapy in thoracic aortic aneurysm shows the best results, being the election treatment for the pathology of the descending thoracic aorta, due to its low peri-operative morbid-mortality. Surgical treatment by retro-peritoneal route and/or endovascular for infra-renal abdominal aortic aneurysm is especially safe in octogenarian patients or in those with a high mortality rate. This institutional cohort show peri-operative and follow-up results similar to those reported in the world literature.

  19. Reparative processes in spleen of rats irradiated with higher daily dose rates of continuous irradiation

    International Nuclear Information System (INIS)

    Mackova, N.; Praslicka, M.; Misurova, E.

    1975-01-01

    Histological and DNA content values were used in evaluating repair processes in the spleen of rats at various intervals following continuous irradiation with daily doses of 50 R, 100 R, 200 R and 500 R (a total dose of 1000 R), and following a single exposure to 1000 R. Histological changes found immediately after irradiation indicated the induction of significant injuries, this mainly as a result of daily doses of 200 R and 500 R. The complete repair of the DNA content and of a number of erythroid elements and also a 70 to 80% regeneration of the white pulp took place within 25 days. The same period was found to be insufficient for the complete repair of megakaryocytes. No signs of repair were observed in spleen in the histological picture or DNA content after a single irradiation with a dose of 1000 R. (author)

  20. Reparative processes in spleen of rats irradiated with higher daily dose rates of continuous irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Mackova, N; Praslicka, M; Misurova, E [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Prirodovedecka Fakulta

    1975-01-01

    Histological and DNA content values were used in evaluating repair processes in the spleen of rats at various intervals following continuous irradiation with daily doses of 50 R, 100 R, 200 R and 500 R (a total dose of 1000 R), and following a single exposure to 1000 R. Histological changes found immediately after irradiation indicated the induction of significant injuries, this mainly as a result of daily doses of 200 R and 500 R. The complete repair of the DNA content and of a number of erythroid elements and also a 70 to 80% regeneration of the white pulp took place within 25 days. The same period was found to be insufficient for the complete repair of megakaryocytes. No signs of repair were observed in spleen in the histological picture or DNA content after a single irradiation with a dose of 1000 R.

  1. Endovascular treatment of intracranial arteriovenous malformations

    International Nuclear Information System (INIS)

    Seruga, T.

    2002-01-01

    Background. The aim of the study was the introduction of endovascular interventional treatment of cerebral arteriovenous malformations (AVM) with superselective embolization with cyanoacrylic polymerisation agent. Case reports. Endovascular embolization was performed in five patients with cerebral AVMs. Three of these patients were presented with intracerebral haemathomas whereas in other two patients, cerebral AVM was an incidental finding. Superselective catheterisation of AVMs was performed and acrylic glue was selectively injected into the nidus. Conclusions. Control cerebral angiography after embolization of AVM showed different results. In one patient, AVM was totally occluded after three sessions and in second case AVM was occluded in a single session. The rate of occlusion in other two cases was estimated between 70% in 80%. Both of these two patients underwent surgery. One patient is still in the process of treatment. Endovascular treatment of cerebral AVMs with superselective embolization with liquid cyanoacrilyc adhesive agent is a safe and effective alternative treatment paths next to microsurgery. Endovascular treatment in combination with radiosurgery could become the method of choice in the therapy of cerebral AVMs in the future. (author)

  2. Pre-irradiation at a low dose-rate blunted p53 response

    International Nuclear Information System (INIS)

    Takahashi, A.; Ohnishi, K.; Asakawa, I.; Tamamoto, T.; Yasumoto, J.; Yuki, K.; Ohnishi, T.; Tachibana, A.

    2003-01-01

    Full text: We have studied whether the p53-centered signal transduction pathway induced by acute radiation is interfered with chronic pre-irradiation at a low dose-rate in human cultured cells and whole body of mice. In squamous cell carcinoma cells, we found that a challenge irradiation with X-ray immediately after chronic irradiation resulted in lower levels of p53 than those observed after the challenge irradiation alone. In addition, the induction of p53-centered apoptosis and the accumulation of its related proteins after the challenge irradiation were strongly correlated with the above-mentioned phenomena. In mouse spleen, the induction of apoptosis and the accumulation of p53 and Bax were observed dose-dependently at 12 h after a challenge irradiation. In contrast, we found significant suppression of them induced by challenge irradiation at a high dose-rate when mice were pre-irradiated with chronic irradiation at a low dose-rate. These findings suggest that chronic pre-irradiation suppressed the p53 function through radiation-induced p53-dependent signal transduction processes. There are numerous papers about p53 functions in apoptosis, radiosensitivity, genomic instability and cancer incidence in cultured cells or animals. According to our data and other findings, since p53 can prevent carcinogenesis, pre-irradiation at a low dose-rate might enhance the predisposition to cancer. Therefore, it is possible that different maximal permissible dose equivalents for the public populations are appropriate. Furthermore, concerning health of human beings, studies of the adaptive responses to radiation are quite important, because the radiation response strongly depends on experience of prior exposure to radiation

  3. Irradiation embrittlement of some 15Kh2MFA pressure vessel steels under varying neutron fluence rates

    Energy Technology Data Exchange (ETDEWEB)

    Valo, M; Bars, B [Technical Research Centre of Finland, Espoo (Finland); Ahlstrand, A [Imatran Voima Oy (IVO), Helsinki (Finland)

    1994-12-31

    Irradiation sensitivity of two forging materials was measured with Charpy-V and fracture mechanic tests, and with different fluence, fluence rate and irradiation time values. Irradiation sensitivity of the materials was found to be less or equal to the current Russian standard, and appears to be well described by the fluence parameter only. A slight additional effect on embrittlement from a long term low fluence irradiation is noticed, but it stays within the total scatter band of data. 7 refs., 17 figs., 4 tabs.

  4. Dose rate distribution of the GammaBeam: 127 irradiator using MCNPX code

    International Nuclear Information System (INIS)

    Gual, Maritza Rodriguez; Batista, Adriana de Souza Medeiros; Pereira, Claubia; Faria, Luiz O. de; Grossi, Pablo Andrade

    2013-01-01

    The GammaBeam - 127 Irradiator is widely used for biological, chemical and medical applications of the gamma irradiation technology using Cobalt 60 radioactive at the Centro de Desenvolvimento da Tecnologia Nuclear CDTN/CNEN, Belo Horizonte, Brazil. The source has maximum activity of 60.000Ci, which is composed by 16 double encapsulated radioactive pencils placed in a rack. The facility is classified by the IAEA as Category II (dry storage facility). The aim of this work is to present a modelling developed to evaluate the dose rates at the irradiation room and the dose distribution at the irradiated products. In addition, the simulations could be used as a predictive tool of dose evaluation in the irradiation facility helping benchmark experiments in new similar facilities. The MCNPX simulated results were compared and validated with radiometric measurements using Fricke and TLDs dosimeters along several positions inside the irradiation room. (author)

  5. The biological effect of 125I seed continuous low dose rate irradiation in CL187 cells

    Directory of Open Access Journals (Sweden)

    Zhuang Hong-Qing

    2009-01-01

    Full Text Available Abstract Background To investigate the effectiveness and mechanism of 125I seed continuous low-dose-rate irradiation on colonic cell line CL187 in vitro. Methods The CL187 cell line was exposed to radiation of 60Coγ ray at high dose rate of 2 Gy/min and 125I seed at low dose rate of 2.77 cGy/h. Radiation responses to different doses and dose rates were evaluated by colony-forming assay. Under 125I seed low dose rate irradiation, a total of 12 culture dishes were randomly divided into 4 groups: Control group, and 2, 5, and 10 Gy irradiation groups. At 48 h after irradiation, apoptosis was detected by Annexin and Propidium iodide (PI staining. Cell cycle arrests were detected by PI staining. In order to investigate the influence of low dose rate irradiation on the MAPK signal transduction, the expression changes of epidermal growth factor receptor (EGFR and Raf under continuous low dose rate irradiation (CLDR and/or EGFR monoclonal antibodies were determined by indirect immunofluorescence. Results The relative biological effect (RBE for 125I seeds compared with 60Co γ ray was 1.41. Apoptosis rates of CL187 cancer cells were 13.74% ± 1.63%, 32.58% ± 3.61%, and 46.27% ± 3.82% after 2 Gy, 5 Gy, and 10 Gy irradiation, respectively; however, the control group apoptosis rate was 1.67% ± 0.19%. G2/M cell cycle arrests of CL187 cancer cells were 42.59% ± 3.21%, 59.84% ± 4.96%, and 34.61% ± 2.79% after 2 Gy, 5 Gy, and 10 Gy irradiation, respectively; however, the control group apoptosis rate was 26.44% ± 2.53%. P 2/M cell cycle arrest. After low dose rate irradiation, EGFR and Raf expression increased, but when EGFR was blocked by a monoclonal antibody, EGFR and Raf expression did not change. Conclusion 125I seeds resulted in more effective inhibition than 60Co γ ray high dose rate irradiation in CL187 cells. Apoptosis following G2/M cell cycle arrest was the main mechanism of cell-killing effects under low dose rate irradiation. CLDR could

  6. Comparative influence of dose rate and radiation nature, on lethality after big mammals irradiation

    International Nuclear Information System (INIS)

    Destombe, C.; Le Fleche, Ph.; Grasseau, A.; Reynal, A.

    1997-01-01

    For the same dose and the 30 days lethality as biological criterion, the dose rate influence is more important than the radiation nature on the results of an big mammals total body irradiation. (authors)

  7. CONTRASTING DOSE-RATE EFFECTS OF GAMMA-IRRADIATION ON RAT SALIVARY-GLAND FUNCTION

    NARCIS (Netherlands)

    VISSINK, A; DOWN, JD; KONINGS, AWT

    The aim of this study was to investigate the effects of Co-60 irradiation delivered at high (HDR) and low (LDR) dose-rates on rat salivary gland function. Total-body irradiation (TBI; total doses 7.5, 10 and 12.5 Gy) was applied from a Co-60 source at dose-rates of 1 cGy/min (LDR) and 40 cGy/min

  8. Modern radiosurgical and endovascular classification schemes for brain arteriovenous malformations.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Lawton, Michael T

    2018-05-04

    Stereotactic radiosurgery (SRS) and endovascular techniques are commonly used for treating brain arteriovenous malformations (bAVMs). They are usually used as ancillary techniques to microsurgery but may also be used as solitary treatment options. Careful patient selection requires a clear estimate of the treatment efficacy and complication rates for the individual patient. As such, classification schemes are an essential part of patient selection paradigm for each treatment modality. While the Spetzler-Martin grading system and its subsequent modifications are commonly used for microsurgical outcome prediction for bAVMs, the same system(s) may not be easily applicable to SRS and endovascular therapy. Several radiosurgical- and endovascular-based grading scales have been proposed for bAVMs. However, a comprehensive review of these systems including a discussion on their relative advantages and disadvantages is missing. This paper is dedicated to modern classification schemes designed for SRS and endovascular techniques.

  9. Near-ultraviolet removal rates for subgingival dental calculus at different irradiation angles

    Science.gov (United States)

    Schoenly, Joshua E.; Seka, Wolf D.; Rechmann, Peter

    2011-07-01

    The laser ablation rate of subgingival dental calculus irradiated at a 400-nm-wavelength, 7.4-mJ pulse energy, and 85- and 20-deg irradiation angles is measured using laser triangulation. Three-dimensional images taken before and after irradiation create a removal map with 6-μm axial resolution. Fifteen human teeth with subgingival calculus are irradiated in vitro under a cooling water spray with an ~300-μm-diam, tenth-order super-Gaussian beam. The average subgingival calculus removal rates for irradiation at 85 and 20 deg are 11.1+/-3.6 and 11.5+/-5.9 μm/pulse, respectively, for depth removal and 4.5+/-1.7×105 and 4.8+/-2.3×105 μm3/pulse, respectively, for volume removal. The ablation rate is constant at each irradiation site but varies between sites because of the large differences in the physical and optical properties of calculus. Comparison of the average depth- and volume-removal rates does not reveal any dependence on the irradiation angle and is likely due to the surface topology of subgingival calculus samples that overshadows any expected angular dependence.

  10. Analysis of gamma irradiator dose rate using spent fuel elements with parallel configuration

    International Nuclear Information System (INIS)

    Setiyanto; Pudjijanto MS; Ardani

    2006-01-01

    To enhance the utilization of the RSG-GAS reactor spent fuel, the gamma irradiator using spent fuel elements as a gamma source is a suitable choice. This irradiator can be used for food sterilization and preservation. The first step before realization, it is necessary to determine the gamma dose rate theoretically. The assessment was realized for parallel configuration fuel elements with the irradiation space can be placed between fuel element series. This analysis of parallel model was choice to compare with the circle model and as long as possible to get more space for irradiation and to do manipulation of irradiation target. Dose rate calculation were done with MCNP, while the estimation of gamma activities of fuel element was realized by OREGEN code with 1 year of average delay time. The calculation result show that the gamma dose rate of parallel model decreased up to 50% relatively compared with the circle model, but the value still enough for sterilization and preservation. Especially for food preservation, this parallel model give more flexible, while the gamma dose rate can be adjusted to the irradiation needed. The conclusion of this assessment showed that the utilization of reactor spent fuels for gamma irradiator with parallel model give more advantage the circle model. (author)

  11. The independence of irradiation creep in austenitic alloys of displacement rate and helium to dpa ratio

    Energy Technology Data Exchange (ETDEWEB)

    Garner, F.A.; Toloczko, M.B. [Pacific Northwest National Lab., Richland, WA (United States); Grossbeck, M.L. [Oak Ridge National Lab., TN (United States)

    1997-04-01

    The majority of high fluence data on the void swelling and irradiation creep of austenitic steels were generated at relatively high displacement rates and relatively low helium/dpa levels that are not characteristic of the conditions anticipated in ITER and other anticipated fusion environments. After reanalyzing the available data, this paper shows that irradiation creep is not directly sensitive to either the helium/dpa ratio or the displacement rate, other than through their possible influence on void swelling, since one component of the irradiation creep rate varies with no correlation to the instantaneous swelling rate. Until recently, however, the non-swelling-related creep component was also thought to exhibit its own strong dependence on displacement rate, increasing at lower fluxes. This perception originally arose from the work of Lewthwaite and Mosedale at temperatures in the 270-350{degrees}C range. More recently this perception was thought to extend to higher irradiation temperatures. It now appears, however, that this interpretation is incorrect, and in fact the steady-state value of the non-swelling component of irradiation creep is actually insensitive to displacement rate. The perceived flux dependence appears to arise from a failure to properly interpret the impact of the transient regime of irradiation creep.

  12. Headache and endovascular procedures.

    Science.gov (United States)

    de Biase, Stefano; Longoni, Marco; Gigli, Gian Luigi; Agostoni, Elio

    2017-05-01

    The International Classification of Headache Disorders (ICHD-3 beta) includes headache attributed to intracranial endovascular procedures (EVPs). The aim of this review is to describe the clinical and pathophysiological aspects of headache related to vascular lesions and EVPs. Current studies regarding this issue are contradictory, although generally favouring headache improvement after EVPs. Further large studies are needed to adequately assess the effect of EVPs on headache.

  13. Endovascular management of delayed post-pancreatectomy haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Pottier, Edwige [Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Department of Radiology, Clichy, Hauts-de-Seine (France); Ronot, Maxime; Vilgrain, Valerie [Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Department of Radiology, Clichy, Hauts-de-Seine (France); University Paris Diderot, Paris (France); INSERM U1149, centre de recherche biomedicale Bichat-Beaujon, CRB3, Paris (France); Gaujoux, Sebastien; Cesaretti, Manuela; Barbier, Louise [APHP, University Hospitals Paris Nord Val de Seine, Beaujon, Department of Surgery, Clichy, Hauts-de-Seine (France); Sauvanet, Alain [University Paris Diderot, Paris (France); APHP, University Hospitals Paris Nord Val de Seine, Beaujon, Department of Surgery, Clichy, Hauts-de-Seine (France)

    2016-10-15

    To assess the patient outcome after endovascular treatment of delayed post-pancreatectomy haemorrhage (PPH) as first-line treatment. Between January 2005 and November 2013, all consecutive patients referred for endovascular treatment of PPH were included. Active bleeding, pseudoaneurysms, collections and the involved artery were recorded on pretreatment CT. Endovascular procedures were classified as technical success (source of bleeding identified on angiogram and treated), technical failure (source of bleeding identified but incompletely treated) and abstention (no abnormality identified, no treatment performed). Factors associated with rebleeding were analysed. Sixty-nine patients (53 men) were included (mean 59 years old (32-75)). Pretreatment CT showed 27 (39 %) active bleeding. In 22 (32 %) cases, no involved artery was identified. Technical success, failure and abstention were observed in 48 (70 %), 9 (13 %) and 12 patients (17 %), respectively. Thirty patients (43 %) experienced rebleeding. Rebleeding rates were 29 %, 58 % and 100 % in case of success, abstention and failure (p < 0.001). Treatment failure/abstention was the only factor associated with rebleeding. Overall, 74 % of the patients were successfully treated by endovascular procedure(s) alone. After a first endovascular procedure for PPH, the rebleeding rate is high and depends upon the success of the procedure. Most patients are successfully treated by endovascular approach(es) alone. (orig.)

  14. Endovascular management of delayed post-pancreatectomy haemorrhage

    International Nuclear Information System (INIS)

    Pottier, Edwige; Ronot, Maxime; Vilgrain, Valerie; Gaujoux, Sebastien; Cesaretti, Manuela; Barbier, Louise; Sauvanet, Alain

    2016-01-01

    To assess the patient outcome after endovascular treatment of delayed post-pancreatectomy haemorrhage (PPH) as first-line treatment. Between January 2005 and November 2013, all consecutive patients referred for endovascular treatment of PPH were included. Active bleeding, pseudoaneurysms, collections and the involved artery were recorded on pretreatment CT. Endovascular procedures were classified as technical success (source of bleeding identified on angiogram and treated), technical failure (source of bleeding identified but incompletely treated) and abstention (no abnormality identified, no treatment performed). Factors associated with rebleeding were analysed. Sixty-nine patients (53 men) were included (mean 59 years old (32-75)). Pretreatment CT showed 27 (39 %) active bleeding. In 22 (32 %) cases, no involved artery was identified. Technical success, failure and abstention were observed in 48 (70 %), 9 (13 %) and 12 patients (17 %), respectively. Thirty patients (43 %) experienced rebleeding. Rebleeding rates were 29 %, 58 % and 100 % in case of success, abstention and failure (p < 0.001). Treatment failure/abstention was the only factor associated with rebleeding. Overall, 74 % of the patients were successfully treated by endovascular procedure(s) alone. After a first endovascular procedure for PPH, the rebleeding rate is high and depends upon the success of the procedure. Most patients are successfully treated by endovascular approach(es) alone. (orig.)

  15. Annual rate of hearing loss falls after fractionated stereotactic irradiation for vestibular schwannoma

    International Nuclear Information System (INIS)

    Sakamoto, Touru; Shirato, Hiroki; Takeichi, Norihito; Aoyama, Hidefumi; Fukuda, Satoshi; Miyasaka, Kazuo

    2001-01-01

    Purpose: The rate of hearing loss in a population before and after irradiation was investigated to determine the effect of irradiation on hearing impairment. Methods and materials: In 72 patients with vestibular schwannoma who received fractionated stereotactic irradiation from 1992 to 1999, 21 had had their hearing levels examined 3 months or more before the treatment. The mean time between the initial examination and treatment was 18.6 months (range: 3-89 months), and the mean time between treatment and the last follow-up was 24.2 months (12-69 months). Thirty-six to 50 Gy in 20-25 fractions over 5 to 6 weeks was given using an X-ray beam from a linear accelerator. Pure tone average (PTA) was measured using the mean hearing level at five frequencies, and the annual rate of hearing loss was defined as [(hearing loss in PTA(dB))/(follow-up period (months)x12)]. Results: The actual cumulative curve of decrease in tumor size of 2 mm or more was 38.3% at 2 years and 80.0% at 3 years. The mean of hearing loss in PTA was 11.6±10.3 dB (-1 to 35 dB) from the initial examination to the start of irradiation and 11.9±14.4 dB (-14 to 37 dB) from the start of irradiation to the last follow-up. The mean annual rates of hearing loss before irradiation and in the 1st, 2nd, 3rd and 4th years after irradiation were, respectively, 18.6, 11.2, 6.2, 5.1, and 5.0 dB/year. The annual rates of hearing loss in the 2nd year (P=0.025) and 3rd year (P=0.018) were significantly slower than the rate before irradiation. Conclusions: The mean annual rate of hearing loss was higher before irradiation than after irradiation, and hearing loss slowed rather than accelerated after irradiation. Although hearing loss after the treatment was usually permanent, fractionated stereotactic irradiation was suggested to be effective to lower the rate of hearing loss

  16. Endovascular treatment in pregnancy

    International Nuclear Information System (INIS)

    Ishii, Akira; Miyamoto, Susumu

    2013-01-01

    There is an increased risk of stroke during pregnancy and the puerperium. Decisions should be made immediately upon transfer to each institution, particularly with respect to when and how to treat the patient. This review highlights the feasibility of endovascular treatment in pregnancy. Most of the pharmaceutical agents and therapeutic devices used in clinical practice can be utilized in pregnant patients. Comprehensive information on the benefits and risks of treatment should be explained to the patient and her family, with particular attention to the safety of the mother and fetus. Radiation exposure to the fetus is also a concern; the hazard can be minimized with optimal protection. Several studies have demonstrated that conventional procedures do not cause serious radiation exposure exceeding the threshold of safety to the fetus. Endovascular therapy can be safely performed for the treatment of acute stroke as in non-pregnant patients with adequate attention to pharmaceutical agents and shielding from radiation. In contrast to therapy for acute stroke, preventive endovascular treatment for asymptomatic lesions remains controversial. Several conditions, such as cerebral aneurysms and arteriovenous malformations, are known to bleed more frequently in pregnancy, but whether the benefits of preventive treatment outweigh the associated risks is unknown. The decision for preventive treatment should be carefully made on a case-by-case basis after extensive discussion with the patient. (author)

  17. Model of the dose rate for a semi industrial irradiation plant. Pt. 2

    International Nuclear Information System (INIS)

    Mangusi, Josefina

    2004-01-01

    The second stage of the model for the absorbed dose rate in air for the enclosure of a half-industrialist irradiation plant operating with cobalt-60 sources holden in plan geometry is presented. The sensibility of the model with the treatment of the support structure of the irradiator is analyzed and verified with experimental measurements with good accord. The model of the absorbed dose rate in air in the case of an interposed material between the radioactive sources and the point of interest includes in its calculation a set of secondary radioactive sources created by the Compton scattering of the primary radiation. The accord of the calculated absorbed dose rate and the experimental measured ones is good. The transit dose due to the irradiator moving until its dwell position is also modeled. The isodose curves for a set of irradiator parallel planes are also generated. (author) [es

  18. [Endovascular surgery in the war].

    Science.gov (United States)

    Reva, V A; Samokhvalov, I M

    2015-01-01

    Rapid growth of medical technologies has led to implementation of endovascular methods of diagnosis and treatment into rapidly developing battlefield surgery. This work based on analysing all available current publications generalizes the data on using endovascular surgery in combat vascular injury. During the Korean war (1950-1953) American surgeons for the first time performed endovascular balloon occlusion of the aorta - the first intravascular intervention carried out in a zone of combat operations. Half a century thereafter, with the beginning of the war in Afghanistan (2001) and in Iraq (2003) surgeons of central hospitals of the USA Armed Forces began performing delayed endovascular operations to the wounded. The development of technologies, advent of mobile angiographs made it possible to later on implement high-tech endovascular interventions in a zone of combat operations. At first, more often they performed implantation of cava filters, somewhat afterward - angioembolization of damaged accessory vessels, stenting and endovascular repair of major arteries. The first in the theatre of war endovascular prosthetic repair of the thoracic aorta for severe closed injury was performed in 2008. Russian experience of using endovascular surgery in combat injuries is limited to diagnostic angiography and regional intraarterial perfusion. Despite the advent of stationary angiographs in large hospitals of the RF Ministry of Defence in the early 1990s, endovascular operations for combat vascular injury are casuistic. Foreign experience in active implementation of endovascular technologies to treatment of war-time injuries has substantiated feasibility of using intravascular interventions in tertiary care military hospitals. Carrying out basic training courses on endovascular surgery should become an organic part of preparing multimodality general battlefield surgeons rendering care on the theatre of combat operations.

  19. Suppression of carcinogenesis in mice by adaptive responses to low dose rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Kazuo; Iwasaki, Toshiyasu; Hoshi, Yuko; Nomura, Takaharu; Ina, Yasuhiro; Tanooka, Hiroshi [Central Research Institute of Electric Power Industry, Low Dose Radiation Research Center, Komae, Tokyo (Japan)

    2003-07-01

    Effects of prolonged low-dose-rate irradiation on the process of carcinogenesis were examined in mice treated with chemical carcinogen or irradiated with high doses of X-rays. Female ICR mice, 5 week-old, 35 in each group, were exposed to gamma-rays from a {sup 137}Cs source in the long-term low dose rate irradiation facility at CRIEPI. The dose rate was 2.6 mGy/hr (A), 0.96 mGy/hr (B), or 0.30 mGy/hr (C). Thirty-five days later, the mice were injected into the groin with 0.5 mg of methylcholanthrene (MC) dissolved in olive oil and irradiation was continued. Cumulative tumor incidences after 216 days following MC injection were 89% in group A, 76% in group B, and 94% in group C. That in non-irradiated control group was 94%. The difference in the tumor incidence between the control and position B was statistically significant, indicating the suppressive effect of the low dose rate irradiation on the process of MC-induced carcinogenesis with an optimum dose rate around 1 mGy/hr. In B6C3F1 mice, although the suppression of tumor incidence was not observed, there was a significant delay in tumor appearance in the irradiated mice between 100-150 days after MC injection. A group of 20 female C57BL/6N mice, 5 weeks old, were exposed to gamma-rays at 0.95 mGy/hr for 5 weeks. Then, they were exposed weekly to 1.8 Gy whole body X-irradiation (300 kVp) for consecutive 4 weeks to induce thymic lymphoma. Another group received only the fractionated irradiation. The first mouse died from thymic lymphoma appeared 89 days after the last irradiation in the group received only the fractionated irradiation, while 110 days in the group combined with the low dose rate irradiation. (author)

  20. Effects of gamma irradiation dose rate on microbiological and physical quality of mushrooms (Agaricus bisporus)

    International Nuclear Information System (INIS)

    Beaulieu, M.; Lacroix, M.; Charbonneau, R.; Laberge, I.; Gagnon, M.

    1992-01-01

    The effects of gamma irradiation (2 kGy) and dose rate of irradiation (4.5 and 32.0 kGy/h) on increasing the shelf-life and some quality properties of the mushrooms (Agaricus bisporus) were investigated during storage at 15 deg C and 90% R.H. The retardation of mushroom growth and ageing by reduction of gamma irradiation dose rate (4.5 kGy) was observed by measurements of the cap opening, the stipe increase, the cap diameter, the weight loss and the color of the caps. The color was measured in order to evaluate the lightness with the L value measurement and the color changes were measured in terms of lightness, hue and chroma. The control of fungal and bacterial diseases were also evaluated. The irradiation of mushrooms at both dose rates of irradiation was found to be effective in lowering microorganism counts initially and throughout storage and increased the shelf-life by four days. This study also showed that mushrooms exposed to a lower dose rate (4.5 kGy/h) of irradiation preserve the whiteness and reduce the stripe increase of mushrooms during storage

  1. Characterization of the neutron irradiation system for use in the Low-Dose-Rate Irradiation Facility at Sandia National Laboratories.

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Manuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-08-01

    The objective of this work was to characterize the neutron irradiation system consisting of americium-241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories (SNL) Low Dose Rate Irradiation Facility (LDRIF). With a total activity of 0.3 TBq (9 Ci), the source consisted of three recycled 241AmBe sources of different activities that had been combined into a single source. The source in its polyethylene shielding will be used in neutron irradiation testing of components. The characterization of the source-shielding system was necessary to evaluate the radiation environment for future experiments. Characterization of the source was also necessary because the documentation for the three component sources and their relative alignment within the Special Form Capsule (SFC) was inadequate. The system consisting of the source and shielding was modeled using Monte Carlo N-Particle transport code (MCNP). The model was validated by benchmarking it against measurements using multiple techniques. To characterize the radiation fields over the full spatial geometry of the irradiation system, it was necessary to use a number of instruments of varying sensitivities. First, the computed photon radiography assisted in determining orientation of the component sources. With the capsule properly oriented inside the shielding, the neutron spectra were measured using a variety of techniques. A N-probe Microspec and a neutron Bubble Dosimeter Spectrometer (BDS) set were used to characterize the neutron spectra/field in several locations. In the third technique, neutron foil activation was used to ascertain the neutron spectra. A high purity germanium (HPGe) detector was used to characterize the photon spectrum. The experimentally measured spectra and the MCNP results compared well. Once the MCNP model was validated to an adequate level of confidence, parametric analyses was performed on the model to optimize for potential

  2. Rate of lens lesion development and the age of mice at time of irradiation

    International Nuclear Information System (INIS)

    Gajewski, A.K.; Majewska, K.; Slowikowska, M.G.

    1976-01-01

    The rate of lens lesion development has been studied in mice irradiated at different age ranging from one day up to one year old mice. The time needed for the first appearance of lens lesion was shortest in groups of mice irradiated at the age of one, two and three days of life, and longest in groups of mice irradiated at the age of 5 days, 1 week and 2 weeks of life. The time needed for the first appearance of lens lesion for mice irradiated between the third week and one year of life was constant. It was longer than for mice irradiated during the first three days of life and shorter than for mice irradiated at 5 up to 14 days of life. In all but one irradiated groups the age at which the first lens lesion occurred differed significantly from the age at which the first senile changes occurred in the lens of control mice. The one exception was the group of mice irradiated at the age of one year. (author)

  3. Studies on rate equations for defects in irradiated solids using the local analysis method

    International Nuclear Information System (INIS)

    Carvalho e Camargo, M.U. de.

    1983-10-01

    The void formation and swelling phenomenon in material for nuclear reactors structures, mainly for fast reactors, has been studied by several authors. A simple calculation covering the basic instance of radiation damage in irradiated solid solution, using the local analysis in rate theory is presented here. A simple description of pratical and fundamental interest for the complex problem of solid solution under irradiation is given. (Author) [pt

  4. Effect of the rate and dose rate of irradiation on the quality of mushrooms, shrimps and marinated poultry

    International Nuclear Information System (INIS)

    Lacroix, M.; Mahrour, A.; Beaulieu, M.; Jobin, M.; Nketsa-Tabiri, J.; Gagnon, M.

    1998-01-01

    In this research programme, three investigations involving irradiation in combination with other preservation treatments are described. The first study evaluated the effect of the gamma irradiation dose rate combined with control storage at 15 deg. C and 90% relative humidity on the biochemical, microbiological and physical quality of mushrooms (Agaricus bisporus). A 2 kGy dose was necessary to control the pathogenic microorganisms and to decrease the ageing process of mushrooms. The shelf-life of the mushrooms, as assessed by colour, was extended by 4 days at the lower dose rate (4.5 kGy/h) and by only 2 days at the higher dose rate (32 kGy/h). The higher dose rate caused stress to the cells and altered cell permeability. The second study was to verify the efficacy of ionizing radiation ( 60 Co) on frozen shrimps in eliminating or reducing the pathogenic bacteria that may occasionally be present and to increase the cold storage life of thawed shrimps. A dose of 2.5 kGy permitted storage at 4 deg. C for 1 month without affecting the quality of the product. The third study investigated the anti-oxidant and anti-microbial properties of the natural substances added to fresh poultry before irradiation. Irradiation of poultry at 5 kGy was found to be highly effective in eliminating Salmonella and reducing the number of spoilage microorganisms to ensure safety and quality. Moreover, use of marinating techniques had a synergistic effect with irradiation in reducing the microbial load and the oxidation rate of unsaturated fatty acids, particularly C18:2. The essential oils in rosemary and thyme were the most potent anti-microbial agents investigated and prevented the deterioration of stored foods by bacteria. Several phenolic compounds with anti-oxidant activities were also isolated from rosemary. (author)

  5. Displacement rate and temperature equivalence in stochastic cluster dynamics simulations of irradiated pure α-Fe

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Aaron [Sandia National Laboratories, Albuquerque, 87185 NM (United States); George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, 30332 GA (United States); Muntifering, Brittany [Sandia National Laboratories, Albuquerque, 87185 NM (United States); Northwestern University, Chicago, 60208 IL (United States); Dingreville, Rémi; Hattar, Khalid [Sandia National Laboratories, Albuquerque, 87185 NM (United States); Capolungo, Laurent, E-mail: laurent@lanl.gov [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, 30332 GA (United States); Material Science and Technology Division, MST-8, Los Alamos National Laboratory, Los Alamos, 87545 NM (United States)

    2016-11-15

    Charged particle irradiation is a frequently used experimental tool to study damage accumulation in metals expected during neutron irradiation. Understanding the correspondence between displacement rate and temperature during such studies is one of several factors that must be taken into account in order to design experiments that produce equivalent damage accumulation to neutron damage conditions. In this study, spatially resolved stochastic cluster dynamics (SRSCD) is used to simulate damage evolution in α-Fe and find displacement rate/temperature pairs under ‘target’ and ‘proxy’ conditions for which the local distribution of vacancies and vacancy clusters is the same as a function of displacement damage. The SRSCD methodology is chosen for this study due to its computational efficiency and ability to simulate damage accumulation in spatially inhomogeneous materials such as thin films. Results are presented for Frenkel pair irradiation and displacement cascade damage in thin films and bulk α-Fe. Holding all other material and irradiation conditions constant, temperature adjustments are shown to successfully make up for changes in displacement rate such that defect concentrations and cluster sizes remain relatively constant. The methodology presented in this study allows for a first-order prediction of the temperature at which ion irradiation experiments (‘proxy’ conditions) should take place in order to approximate neutron irradiation (‘target’ conditions).

  6. Relative biological effectiveness of 125I seeds for low-dose-rate irradiation of PANC-1

    International Nuclear Information System (INIS)

    Wang Jidong; Wang Junjie; Zhuang Hongqing; Liao Anyan; Zhao Yong

    2008-01-01

    Objective: To investigate the relative biological effectiveness(RBE) of National Model 6711 125 I seeds and the response patterns of PANC-1 exposed to 125 I seeds irradiation. Methods: PANC-1 cells in exponential growth were irradiated at initial dose rate of 2.59 cGy/h in vitro and exposed to 1, 2, 4, 6, 8 and 10 Gy. Meanwhile, the other part of cells were exposed to the same doses by 60 Co at dose rate of 2.21 Gy/min. After irradiation, the cells were stained by trypan blue to measure the cellular mortality rate and to compare the changes along with plating times of 12, 24, 48 and 72 h after 4 Gy. The colonies were counted to obtain the plating efficiencies by colony-forming assay and the cell surviving faction was calculated to plot cell survival curves, and RBE of 125 I seeds relative to 60 Co was determined. Results: The cell death rate for continuous low- dose-rate (LDR) irradiation by 125 I seeds was greater than 60 Co at the same doses above or equal to 4 Gy. After 4 Gy irradiation, the cellular mortality rates were increased with times. The difference was significant between 125 I seeds and 60 Co. The survival fractions of 125 I were lower than those of 60 Co, and the RBE of 125 I relative to 60 Co was determined to be 1.45. Conclusion: The cell-killing effects for continuous low-dose-rate (LDR) irradiation by 125 I seeds are greater than acute high-dose-rate of 60 Co. (authors)

  7. Virtual reality simulation for the optimization of endovascular procedures: current perspectives

    Directory of Open Access Journals (Sweden)

    Rudarakanchana N

    2015-03-01

    Full Text Available Nung Rudarakanchana,1 Isabelle Van Herzeele,2 Liesbeth Desender,2 Nicholas JW Cheshire1 1Department of Surgery, Imperial College London, London, UK; 2Department of Thoracic and Vascular Surgery, Ghent University Hospital, Ghent, BelgiumOn behalf of EVEREST (European Virtual reality Endovascular RESearch TeamAbstract: Endovascular technologies are rapidly evolving, often requiring coordination and cooperation between clinicians and technicians from diverse specialties. These multidisciplinary interactions lead to challenges that are reflected in the high rate of errors occurring during endovascular procedures. Endovascular virtual reality (VR simulation has evolved from simple benchtop devices to full physic simulators with advanced haptics and dynamic imaging and physiological controls. The latest developments in this field include the use of fully immersive simulated hybrid angiosuites to train whole endovascular teams in crisis resource management and novel technologies that enable practitioners to build VR simulations based on patient-specific anatomy. As our understanding of the skills, both technical and nontechnical, required for optimal endovascular performance improves, the requisite tools for objective assessment of these skills are being developed and will further enable the use of VR simulation in the training and assessment of endovascular interventionalists and their entire teams. Simulation training that allows deliberate practice without danger to patients may be key to bridging the gap between new endovascular technology and improved patient outcomes.Keywords: virtual reality, simulation, endovascular, aneurysm

  8. Complications of endovascular treatment of cerebral aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Orrù, Emanuele, E-mail: surgeon.ema@gmail.com [Neuroradiology Department, Padua University Hospital, Via Giustiniani 2, Padua 35128 (Italy); Roccatagliata, Luca, E-mail: lroccatagliata@neurologia.unige.it [Neuroradiology Department, IRCCS San Martino University Hospital and IST, Largo Rosanna Benzi 10, Genoa 16132 (Italy); Department of Health Sciences (DISSAL), University of Genoa (Italy); Cester, Giacomo, E-mail: giacomo.cester@sanita.padova.it [Neuroradiology Department, Padua University Hospital, Via Giustiniani 2, Padua 35128 (Italy); Causin, Francesco, E-mail: francesco.causin@sanita.padova.it [Neuroradiology Department, Padua University Hospital, Via Giustiniani 2, Padua 35128 (Italy); Castellan, Lucio, E-mail: lucio.castellan@hsanmartino.it [Neuroradiology Department, IRCCS San Martino University Hospital and IST, Largo Rosanna Benzi 10, Genoa 16132 (Italy)

    2013-10-01

    The number of neuroendovascular treatments of both ruptured and unruptured aneurysms has increased substantially in the last two decades. Complications of endovascular treatments of cerebral aneurysms are rare but can potentially lead to acute worsening of the neurological status, to new neurological deficits or death. Some of the possible complications, such as vascular access site complications or systemic side effects associated with contrast medium (e.g. contrast medium allergy, contrast induced nephropathy) can also be encountered in diagnostic angiography. The most common complications of endovascular treatment of cerebral aneurysms are related to acute thromboembolic events and perforation of the aneurysm. Overall, the reported rate of thromboembolic complications ranges between 4.7% and 12.5% while the rate of intraprocedural rupture of cerebral aneurysms is about 0.7% in patients with unruptured aneurysms and about 4.1% in patients with previously ruptured aneurysms. Thromboembolic and hemorrhagic complications may occur during different phases of endovascular procedures and are related to different technical, clinical and anatomic reasons. A thorough knowledge of the different aspects of these complications can reduce the risk of their occurrence and minimize their clinical sequelae. A deep understanding of complications and of their management is thus part of the best standard of care.

  9. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    Science.gov (United States)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  10. Dark noise rates in irradiated silicon photomultiplier arrays

    Energy Technology Data Exchange (ETDEWEB)

    Bachmann, Sebastian; Comerma, Albert; Gerick, David; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Kecke, Matthieu; Leverington, Blake; Mazorra de Cos, Jose; Mitzel, Dominik; Neuner, Max; Uwer, Ulrich [Physikalisches Institut, Universitaet Heidelberg (Germany); Collaboration: LHCb-Collaboration

    2016-07-01

    The planned downstream tracking system - the Scintillating Fibre Tracker - for the LHCb upgrade uses silicon photomultiplier (SiPM) arrays of 128 channels to read out mats made of 250 μm diameter scintillating fibres. In the LHCb environment the neutron flux degrades the silicon detectors to the edge of an acceptable performance in terms of DCR. Studies have shown that the dark count rate (DCR) of the SiPMs increases linearly with the neutron flux. Towards the end of the designed lifetime of the experiment the DCR per SiPM channel operated at T = -40 C is expected to reach a few MHz after partial annealing. To reduce the impact of the DCR - while at the same time provide efficient hit reconstruction - a clustering algorithm is developed to separate signal from noise. A brief introduction into the custom designed read-out ASIC and the cluster algorithm are presented along with the studies of the dark count cluster rate dependency on the neutron flux, the DCR per channel and the effects of the applied signal thresholds for the clustering algorithm.

  11. Degradation and annealing studies on gamma rays irradiated COTS PPD CISs at different dose rates

    International Nuclear Information System (INIS)

    Wang, Zujun; Ma, Yingwu; Liu, Jing; Xue, Yuan; He, Baoping; Yao, Zhibin; Huang, Shaoyan; Liu, Minbo; Sheng, Jiangkun

    2016-01-01

    The degradation and annealing studies on Colbalt-60 gamma-rays irradiated commercial-off-the-shelf (COTS) pinned photodiode (PPD) CMOS image sensors (CISs) at the various dose rates are presented. The irradiation experiments of COTS PPD CISs are carried out at 0.3, 3.0 and 30.0 rad(Si)/s. The COTS PPD CISs are manufactured using a standard 0.18-μm CMOS technology with four-transistor pixel PPD architecture. The behavior of the tested CISs shows a remarkable degradation after irradiation and differs in the dose rates. The dark current, dark signal non-uniformity (DSNU), random noise, saturation output, signal to noise ratio (SNR), and dynamic range (DR) versus the total ionizing dose (TID) at the various dose rates are investigated. The tendency of dark current, DSNU, and random noise increase and saturation output, SNR, and DR to decrease at 3.0 rad(Si)/s are far greater than those at 0.3 and 30.0 rad(Si)/s. The damage mechanisms caused by TID irradiation at the various dose rates are also analyzed. The annealing tests are carried out at room temperature with unbiased conditions after irradiation.

  12. Degradation and annealing studies on gamma rays irradiated COTS PPD CISs at different dose rates

    Science.gov (United States)

    Wang, Zujun; Ma, Yingwu; Liu, Jing; Xue, Yuan; He, Baoping; Yao, Zhibin; Huang, Shaoyan; Liu, Minbo; Sheng, Jiangkun

    2016-06-01

    The degradation and annealing studies on Colbalt-60 gamma-rays irradiated commercial-off-the-shelf (COTS) pinned photodiode (PPD) CMOS image sensors (CISs) at the various dose rates are presented. The irradiation experiments of COTS PPD CISs are carried out at 0.3, 3.0 and 30.0 rad(Si)/s. The COTS PPD CISs are manufactured using a standard 0.18-μm CMOS technology with four-transistor pixel PPD architecture. The behavior of the tested CISs shows a remarkable degradation after irradiation and differs in the dose rates. The dark current, dark signal non-uniformity (DSNU), random noise, saturation output, signal to noise ratio (SNR), and dynamic range (DR) versus the total ionizing dose (TID) at the various dose rates are investigated. The tendency of dark current, DSNU, and random noise increase and saturation output, SNR, and DR to decrease at 3.0 rad(Si)/s are far greater than those at 0.3 and 30.0 rad(Si)/s. The damage mechanisms caused by TID irradiation at the various dose rates are also analyzed. The annealing tests are carried out at room temperature with unbiased conditions after irradiation.

  13. Late effects of chronic low dose-rate γ-rays irradiation on mice

    International Nuclear Information System (INIS)

    Tanaka, Satoshi; Sasagawa, Sumiko; Ichinohe, Kazuaki; Matsumoto, Tsuneya; Otsu, Hiroshi; Sato, Fumiaki

    2002-01-01

    To evaluate late biological effects of chronic low dose-rate radiation, we are conducting two experiments. Experiment 1 - Late effects of chronic low dose-rate g-rays irradiation on SPF mice, using life-span and pathological changes as parameters. Continuous irradiation with g-rays for 400 days was performed using 137 Cs γ-rays at dose-rates of 20 mGy/day, 1 mGy/day and 0.05 mGy/day with accumulated doses equivalent to 8,000 mGy, 400 mGy and 20 mGy, respectively. All mice were kept until they died a natural death. As of 2002 March 31, 3,999 of the total 4,000 mice have died. Preliminary analyses of data show that 20 mGy/day suggested a shortened life span in both sexes. Partial results show that the most common lethal neoplasms in the pooled data of non-irradiated control and irradiated male mice, in order of frequency, were neoplasms of the lymphohematopoietic system, liver, and lung. In female mice, neoplasms of the lymphohematopoietic system, soft tissue, and endocrine system were common. Experiment 2 - Effects on the progeny of chronic low dose-rate g-ray irradiated SPF mice: pilot study, was started in 1999 and is currently in progress. (author)

  14. Pre-irradiation at a low dose-rate blunted p53 response

    International Nuclear Information System (INIS)

    Takahashi, Akihisa

    2002-01-01

    We investigated whether chronic irradiation at a low dose-rate interferes with the p53-centered signal transduction pathyway induced by radiation in human cultured cells and C57BL/6N mice. In in vitro experiments, we found that a challenge with X-ray irradiation immediately after chronic irradiation resulted in lower levels of p53 than those observed after the challenge alone in glioblastoma cells (A-172). In addition, the levels of p53-centered apoptosis and its related proteins after the challenge were strongly correlated with the above-mentioned phenomena in squamous cell carcinoma cells (SAS/neo). In in vivo experiments, the accumulation of p53 and Bax, and the induction of apoptosis were observed dose-dependently in mouse spleen at 12 h after a challenge with X-rays (3.0 Gy). However, we found significant suppression of p53 and Bax accumulation and the induction of apoptosis 12 h after challenge irradiation at 3.0 Gy with a high doses-rate following chronic pre-irradiation (1.5 Gy, 0.001 Gy/min). These findings suggest that chronic pre-irradiation suppressed the p53 function through radiation-induced signaling and/or p53 stability. (author)

  15. Overview of Radiosensitivity of Human Tumor Cells to Low-Dose-Rate Irradiation

    International Nuclear Information System (INIS)

    Williams, Jerry R.; Zhang Yonggang; Zhou Haoming; Gridley, Daila S.; Koch, Cameron J.; Slater, James M.; Little, John B.

    2008-01-01

    Purpose: We compared clonogenic survival in 27 human tumor cell lines that vary in genotype after low-dose-rate (LDR) or high-dose rate (HDR) irradiation. We measured susceptibility to LDR-induced redistribution in the cell cycle in eight of these cell lines. Methods and Materials: We measured clonogenic survival after up to 96 hours of LDR (0.25 Gy/h) irradiation. We compared these with clonogenic survival after HDR irradiation (50 Gy/h). Using flow cytometry, we measured LDR-induced redistribution as a function of time during LDR irradiation in eight of these cell lines. Results: Coefficients that describe clonogenic survival after both LDR and HDR irradiation segregate into four radiosensitivity groups that associate with cell genotype: mutant (mut)ATM, wild-type TP53, mutTP53, and an unidentified gene in radioresistant glioma cells. The LDR and HDR radiosensitivity correlates at lower doses (∼2 Gy HDR, ∼6 Gy LDR), but not at higher doses (HDR > 4 Gy; LDR > 6 Gy). The rate of LDR-induced loss of clonogenic survival changes at approximately 24 hours; wild-type TP53 cells become more resistant and mutTP53 cells become more sensitive. Redistribution induced by LDR irradiation also changes at approximately 24 hours. Conclusions: Radiosensitivity of human tumor cells to both LDR and HDR irradiation is genotype dependent. Analysis of coefficients that describe cellular radiosensitivity segregates 27 cell lines into four statistically distinct groups, each associating with specific genotypes. Changes in cellular radiosensitivity and redistribution in the cell cycle are strongly time dependent. Our data establish a genotype-dependent time-dependent model that predicts clonogenic survival, explains the inverse dose-rate effect, and suggests possible clinical applications

  16. Dose rate on the environment generated by a gamma irradiation plant

    International Nuclear Information System (INIS)

    Mangussi, J.

    2011-01-01

    A model for the absorbed dose rate calculation on the surroundings of a gamma irradiation plant is developed. In such plants, a part of the radiation emitted upwards reach the outdoors. The Compton scatterings on the wall of the exhausting pipes through de plant roof and on the outdoors air are modelled. The absorbed dose rate generated by the scattered radiation reaching the outdoors floor is calculated. The results of the models, to be used for the irradiation plant design and for the environmental studies, are showed on tables and graphics. (author) [es

  17. Aging irradiation of polymers. Dose-rate and test sequence influence

    International Nuclear Information System (INIS)

    Alba, C.; Carlin, F.; Chenion, J.; Lemaire, F.; Le Meur, M.; Petitjean, M.

    1984-05-01

    This work brings up results of the irradiation dose-rate influence on mechanical and electrical properties of technical polymer materials evolution. Polymer samples were subjected to 3.3.10 -2 Gy.s -1 and 2.8.10 -1 Gy.s -1 dose-rate. Heat and radiation simultaneous action is usualy simulated sequentialy. The hardest simulation on the polymer is the sequence of irradiation followed by thermal aging not the reverse. This study was carried out on eight polymer materials among those used in the electrical appliances for P.W.R. nuclear power plants [fr

  18. Possible impact of iridium-192 source centering on restenosis rate after femoro-popliteal angioplasty and endovascular brachytherapy in Vienna-2 study

    International Nuclear Information System (INIS)

    Pokrajac, Boris; Schmid, Rainer; Kirisits, Christian; Mock, Ulrike; Fellner, Claudia; Wambersie, Andre; Poetter, Richard; Minar, Erich

    2002-01-01

    Purpose: Endovascular brachytherapy (EVBT) has been proven to significantly reduce restenosis after percutaneous transluminal angioplasty (PTA). The object of this analysis was to assess the possible correlation between iridium-192 source non-centering and angiographic-determined restenosis. Materials and methods: A total of 113 patients with long-segment lesions of the superficial femoro-popliteal artery (SFA) were randomized to receive either PTA alone or PTA followed by EVBT in the Vienna-2 study. This analysis was performed on a subgroup of 34 out of 57 patients, who received PTA+EVBT. Angiographic restenosis was defined as lumen reduction of more than 50%. Angiograms taken immediately after PTA (34 patients) and at follow-up (25 patients) were analyzed. The distance between the vessel wall and the actual position of the source at the time of EVBT was measured (in mm) and correlated with the follow-up vessel lumen diameter. Measurements were performed at points at a distance of 10 mm from each other. The dose was determined at the luminal surface and at the reference depth of 2 mm into the vessel wall for different distances from the source. Results: Among the 622 measured points, 62 (10.0%) were within restenotic areas; 560 (90.0%) were in arterial segments without proven angiographic restenosis. As far as source centering is concerned, 7.9% of restenotic points were observed when the maximum distance to the arterial wall was 5 mm. Conclusions: The proportion of restenotic points significantly increased with source non-centering. This observation was interpreted as being related to a decrease in dose at the target. When the maximum distance between the source and the vessel surface was >5 mm, the dose at the reference depth (2 mm into the vessel wall) decreased to values lower than 5 Gy

  19. Effects of low dose rate irradiation on induction of myeloid leukemia in mice

    International Nuclear Information System (INIS)

    Furuse, Takeshi

    1999-01-01

    We investigated the induction of myeloid leukemia and other kinds of neoplasias in C3H male mice irradiated at several dose rate levels. We compared the incidence of neoplasias among these groups, obtained dose and dose rate effectiveness factors (DDREF) for myeloid leukemia. C3H/He male mice were exposed to whole body gamma-ray irradiation at 8 weeks of age. All mice were maintained for their entire life span and teh pathologically examined after their death. Radiation at a high dose-rate of 882 mGy/min (group H), a medium dose-rate of 95.6 mGy/min (group M), and low dose-rates of 0.298 mGy/min (group L-A), 0.067 mGy/min (group L-B) or 0.016 mGy/min (group L-C) were delivered from 137 Cs sources. The mice in group L were irradiated continuously for 22 hours daily up to total doses of 1, 2, 3, 4, 10 Gy over a period of 3 days to 200 days. As for the induction of neoplasias, myeloid leukemia developed significantly more frequently in irradiated groups than in unirradiated groups. The time distribution of mice dying from myeloid leukemia did not show a difference between groups H and L. The incidence of myeloid leukemia showed a greater increase in the high dose-rate groups than in the low and medium dose-rate groups in the dose range over 2 Gy, it also showed significant increases in the groups irradiated with 1 Gy of various dose rate, but the difference between these groups was not clear. These dose effect curves had their highest values on each curve at about 3 Gy. We obtained DDREF values of 2-3 by linear fittings for their dose response curves of dose ranges in which leukemia incidences were increasing. (author)

  20. Endovascular Treatment Strategies in Aortoiliac Occlusion

    International Nuclear Information System (INIS)

    Ozkan, Ugur; Oguzkurt, Levent; Tercan, Fahri; Gumus, Burcak

    2009-01-01

    The aim of this study was to report our experience in endovascular treatment of total aortoiliac occlusion. Five patients who underwent endovascular recanalization procedures including manual aspiration thrombectomy, balloon angioplasty, and stent placement for total aortoiliac occlusion in a 4-year period were reviewed retrospectively. The mean age of patients was 51 years (range, 43 to 58 years). All patients had abdominal aorta and bilateral common iliac artery occlusion with or without external iliac artery occlusion. All patients either had a contraindication to surgery or refused it. Initial technical success was obtained in four of five (80%) patients. Endovascular techniques were successful in four patients who had good distal runoff and short-segment aortoiliac occlusion, but failed in a patient who had the worst distal runoff and long-segment aortoiliac occlusion. We observed two major complications, one of which was bilateral rupture of the common iliac arteries treated with covered stent placement. Another patient had extension of intra-aortic thrombus into the iliac stent after primary stenting. This was successfully treated with manual aspiration thrombectomy. Aortic and iliac stents remained patent during the follow-up period (median, 18 months; range, 3 to 26 months) in four patients. Primary patency rates at 6, 12, and 24 months were all 80%. In conclusion, endovascular treatment can be an alternative for aortoiliac occlusion in selected patients. Short- to midterm follow-up so far is satisfactory. Removal of intra-aortic thrombus with manual aspiration thrombectomy before balloon angioplasty and/or stenting is possible and a good alternative to thrombolysis.

  1. Treatment results by uneven fractionated irradiation, low-dose rate telecobalt therapy as a boost, and intraoperative irradiation for malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Shogo; Takai, Yoshihiro; Nemoto, Kenji; Ogawa, Yoshihiro; Kakuto, Yoshihisa; Hoshi, Akihiko; Sakamoto, Kiyohiko; Kayama, Takamasa; Yoshimoto, Takashi (Tohoku Univ., Sendai (Japan). School of Medicine)

    1992-08-01

    The prognosis of malignant glioma is extremely poor. We applied conventionally fractionated irradiation combined with 1-(4-aminio-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU), uneven fractionated irradiation with ACNU, low dose rate telecobalt therapy as a boost, and intraoperative irradiation against 110 malignant gliomas to investigate the efficacy of these methods as alternative treatments for malignant glioma. Although local tumor control by uneven fractionated irradiation was better than that by the other methods, no significant improvement was obtained in survival rates. As a result of multiple regression analysis, age and histology were major factors for survival rates, and the difference of treatment methods was not important. Both low-dose rate telecobalt therapy as a boost and intraoperative irradiation showed little advantage because of the high risk of brain necrosis associated with them. (author).

  2. DNA repair capacity and rate of excision repair in UV-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Inoue, Masao; Takebe, Hiraku.

    1978-01-01

    Repair capacities of five mammalian cell strains were measured by colony-forming ability, HCR of UV-irradiated virus, UDS, pyrimidine dimer excision, and semi-conservative DNA replication. Colony-forming ability of UV-irradiated cells was high for human amnion FL cells and mouse L cells, slightly low for African green monkey CV-1 cells, and extremely low for xeroderma pigmentosum cells. HCR of UV-irradiated Herpes simplex virus was high in CV-1 cells, FL and normal human fibroblast cells, low in both XP and L cells. The amount of UDS was high in FL and normal human fibroblast cells, considerably low in CV-1 cells, and essentially no UDS was observed in XP cells. Rate of UDS after UV-irradiation was slower for CV-1 cells than FL and human fibroblast cells. Rate of the excision of thymine-containing dimers from the acid-insoluble fraction during post-irradiation incubation of the cells was rapid in FL and normal human cells and slow in CV-1 cells, and no excision took place in XP cells. Semi-conservative DNA synthesis was reduced after UV-irradiation in all cell lines, but subsequently recovered in FL, normal human and CV-1 cells. The onset of recovery was 4 h after UV-irradiation for FL and normal human cells, but about 6 h for CV-1 cells. The apparent intermediate repair of CV-1 cells except for HCR may be related to the slow rate of excision repair. ''Patch and cut'' model is more favorable than ''cut and patch'' model to elucidate these results. (auth.)

  3. Relationship of dose rate and total dose to responses of continuously irradiated beagles

    International Nuclear Information System (INIS)

    Fritz, T.E.; Norris, W.P.; Tolle, D.V.; Seed, T.M.; Poole, C.M.; Lombard, L.S.; Doyle, D.E.

    1978-01-01

    Young-adult beagles were exposed continuously (22 hours/day) to 60 Co gamma rays in a specially constructed facility. The exposure rates were 5, 19, 17 or 35 R/day, and the exposures were terminated at 600, 1400, 2000 or 4000 R. A total of 354 dogs were irradiated; 221 are still alive as long-term survivors, some after more than 2000 days. The data on survival of these dogs, coupled with data from similar preliminary experiments, allow an estimate of the LD 50 for gamma-ray exposures given at a number of exposure rates. They also allow comparison of the relativeimportance of dose rate and total dose, and the interaction of these two variables, in the early and late effects after protracted irradiation. The LD 50 for the beagle increases from 344 R (258 rads) delivered at 15 R/minute to approximately 4000 R (approximately 3000 rads) at 10 R/day. Over this entire range, the LD 50 is dependent upon haematopoietic damage. At 5 R/day and less, no definitive LD 50 can be determined; there is nearly normal continued haematopoietic function, survival is prolonged, and the dogs manifest varied individual responses in the organ systems. Although the experiment is not complete, interim data allow serveral important conclusions. Terminated exposures, while not as effective as irradiation continued until death, can produce myelogenous leukaemia at the same exposure rate, 10 R/day. More importantly, at the same total accumulated dose, lower exposure rates appear more damaging than higher rates on the basis of the rate and degree of haematological recovery that occurs after termination of irradiation. Thus, the rate of haematologic depression, the nadir of the depression and the rate of recovery are dependent upon exposure rate; the latter is inversely related and the first two are directly related to exposure rate. ( author)

  4. Prediction of rate of CO2 assimilation of leaf lettuce under low light irradiation during storage

    International Nuclear Information System (INIS)

    Uchino, T.; Harada, F.; Hu, W.

    2003-01-01

    The rate of CO 2 assimilation of leaf lettuce changed with its respiration rate and gas constitution in a storage chamber. The optimum irradiance on the surface of leaf lettuce during storage using low light irradiation can be obtained by the prediction of the rate of CO 2 assimilation. For the above mentioned purpose the following equation were derived. -kd[C]/dt=0.5(1-f)I([C]-Γ/4.5[C]+10.5Γ)-ae -bt where, k: proportional constant (4.87×10 -3 mol⋅m -2 ) [C]: CO 2 concentration (ppm), t: time (h), f: fraction of light not absorbed by chloroplasts (0.23), I: irradiance (μmol⋅m-2⋅s -1 ), Γ: CO 2 compensation point without respiration (21.5ppm), a, b: parameters (0.308μmol⋅m -2 ⋅s -1 , 0.010h -1 ). Calculated values of rate of CO 2 assimilation by the equation agreed well with experimental ones at 3.4 and 6.5μmol⋅m -2 ⋅s -1 of irradiance, so it appeared that the assimilation rate could be sufficiently predicted

  5. The effect of exposure rate of the growth of soybean seedlings grown from gamma irradiated seeds

    International Nuclear Information System (INIS)

    Mohd Yusof, A.; Grunewald, R.

    1981-01-01

    The effect of the gamma ( 137 Cs) total exposure rate of 25 kR delivered at three different exposure rates (887 R/min, 159 R/min and 48 R/min) on soybean seeds was studied by measuring seedling height, cotyledon area, fresh weight, dry weight, Co 2 fixation and RuDP carboxylase activity. The dry weight, CO 2 fixation and irradiated imbibed groups did not show any correlation with exposure rate. Exposure rate effect was shown for the first stage out, no further correlation was observed in the subsequent stages, probably due to the recovery and repair mechanisms that take place as the seedling increases with age. The absence of an exposure rate effect on irradiated imbibed group may be explained in terms of non-detectable damage at a very high dose, since these seedlings exhibited effects that are similar to the effects of seeds exposed to an acute radiation dose. (author)

  6. Model of the dose rate for a semi industrial irradiation plant. Pt. 1

    International Nuclear Information System (INIS)

    Mangussi, Josefina; Gomez, Enzo

    2003-01-01

    This paper introduces the first stage of a software for visualization of isodose curves, at the irradiation area of a semi-industrial irradiation plant operating with cobalt-60. The dose rate is calculated in each point of the area as the sum of the contributions of each one of the radioactive sources located in the irradiator. The regions of the space with equal dose rate were solved as lines in the Cartesian planes with a set of programs written in Free Pascal. In this first stage, external programs and utilities were used for the visualization and the validation of simulated and experimental data. In future stages, visualization modules will be integrated into the software to produce graphs from ASCII outputs. (author)

  7. Effect of prolonged irradiation by low dose-rate ionizing radiation on the hemopoiesis of mice

    Energy Technology Data Exchange (ETDEWEB)

    Yanai, Takanori; Shirata, Katsutoshi; Saitou, Mikio; Tanaka, Satoshi; Onodera, Junichi; Otsu, Hiroshi; Sato, Fumiaki [Institute for Environmental Sciences, Department of Radiobiology, Rokkasho, Aomori (Japan)

    1999-07-01

    To evaluate effects of prolonged irradiation by low dose-rate ionizing radiation on the hemopoiesis of mice, SPF C3H/HeN female mice were irradiated by {sup 137}Cs {gamma}-rays with doses of 1-8 Gy at the dose rate of 20 mGy (22 h-day){sup -1}. After irradiation, the number of hemopoietic cells contained in bone marrow was determined by the methods of CFU-S and CFU-GM assay, and the number of peripheral blood cells was counted. It was shown that the day 12-CFU-S, which is in the earlier stage of differentiation, decreased as the dose increased. Decreases of the numbers of day 7-CFU-S and CFU-GM were also observed. However, there were no remarkable changes in the number of peripheral blood cells. (author)

  8. Effect of prolonged irradiation by low dose-rate ionizing radiation on the hemopoiesis of mice

    Energy Technology Data Exchange (ETDEWEB)

    Yanai, Takanori; Shirata, Katsutoshi; Yamada, Yutaka; Saitou, Mikio; Izumi, Jun; Tanaka, Satoshi; Otsu, Hiroshi; Sato, Fumiaki [Institute for Environmental Sciences, Rokkasho, Aomori (Japan)

    2000-07-01

    For evaluation of effects of prolonged irradiation by low dose-rate ionizing radiation on the hemopoiesis of mice, SPF C3H/HeN female mice were irradiated with {sup 137}Cs {gamma}-rays with doses of 1-4 Gy at the dose rate of 20 mGy/22h-day. After irradiation, the number of hemopoietic cells contained in spleen was determined by the methods of CFU-S and CFU-GM assay, and the number of peripheral blood cells was counted. It was shown that the number of CFU-S colonies on day 12, which is in the earlier stage of differentiation, decreased as dose increased. No remarkable changes in the number of peripheral blood cells, however, were observed. (author)

  9. Effect of radiation doses rate on SOS response induction in irradiated Escherichia coli Cells

    International Nuclear Information System (INIS)

    Cuetara Lugo, Elizabeth B.; Fuentes Lorenzo, Jorge L.; Almeida Varela, Eliseo; Prieto Miranda, Enrique F.; Sanchez Lamar, Angel; Llagostera Casal, Montserrat

    2005-01-01

    The present work is aimed to study the effect of radiation dose rate on the induction of SOS response in Escherichia coli cells. We measured the induction of sul A reporter gene in PQ-37 (SOS Chromotest) cells. Lead devises were built with different diameter and these were used for diminishing the dose rate of PX- -30M irradiator. Our results show that radiation doses rate significantly modifies the induction of SOS response. Induction factor increases proportionally to doses rate in Escherichia coli cells defective to nucleotide excision repair (uvrA), but not in wild type cells. We conclude that the dose rate affects the level of induction of SOS response

  10. Allograft tissue irradiation and failure rate after anterior cruciate ligament reconstruction: A systematic review.

    Science.gov (United States)

    Dashe, Jesse; Parisien, Robert L; Cusano, Antonio; Curry, Emily J; Bedi, Asheesh; Li, Xinning

    2016-06-18

    To evaluate whether anterior cruciate ligament (ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate. A literature search was conducted using PubMed, Cochrane, and Google. The following search terms were used: "Gamma irradiation AND anterior cruciate ligament AND allograft" with a return of 30 items. Filters used included: English language, years 1990-2015. There were 6 hits that were not reviewed, as there were only abstracts available. Another 5 hits were discarded, as they did not pertain to the topic of interest. There were 9 more articles that were excluded: Three studies were performed on animals and 6 studies were meta-analyses. Therefore, a total of 10 articles were applicable to review. There is a delicate dosing crossover where gamma irradiation is both effective for sterility without catastrophically compromising the structural integrity of the graft. Of note, low dose irradiation is considered less than 2.0 Mrad, moderate dose is between 2.1-2.4 Mrad, and high dose is greater than or equal to 2.5 Mrad. Based upon the results of the literature search, the optimal threshold for sterilization was found to be sterilization at less than 2.2 Mrad of gamma irradiation with the important caveat of being performed at low temperatures. The graft selection process also must include thorough donor screening and testing as well as harvesting the tissue in a sterile fashion. Utilization of higher dose (≥ 2.5 Mrad) of irradiation causes greater allograft tissue laxity that results in greater graft failure rate clinically in patients after ACL reconstruction. Allograft ACL graft gamma irradiated with less than 2.2 Mrad appears to be a reasonable alternative to autograft for patients above 25 years of age.

  11. Regeneration of Murine Hair Follicles is Inhibited by Low-Dose-Rate Gamma Irradiation.

    Science.gov (United States)

    Sugaya, Kimihiko; Hirobe, Tomohisa; Ishihara, Yoshie; Inoue, Sonoe

    2016-10-01

    To determine whether the effects of low-dose-rate gamma (γ) irradiation are identifiable in the regeneration of murine hair follicles, we irradiated whole bodies of C57BL/10JHir mice in the first telogen phase of the hair cycle with 137 Cs γ-rays. The mice were examined for effects on hair follicles, including number, morphology, and pigmentation in the second anagen phase. Effects of γ-radiation on melanocyte stem cells were also investigated by the indirect immunolabeling of tyrosinase-related protein 2 (TRP2). Irradiated skin showed a decrease in hair follicle density and the induction of curved hair follicles along with the presence of white hairs and hypopigmented hair bulbs. There was a small, but not significant, change in the number of TRP2-positive melanocyte stem cells in the hair bulge region of the irradiated skin. These results suggest that low-dose rate γ-irradiation does not deplete melanocyte stem cells, but can damage stem cells and progenitors for both keratinocytes and melanocytes, thereby affecting the structure and pigmentation of regenerated hair follicles in the 2 nd anagen phase.

  12. Facility for gamma irradiations of cultured cells at low dose rates: design, physical characteristics and functioning

    International Nuclear Information System (INIS)

    Esposito, Giuseppe; Anello, Pasquale; Pecchia, Ilaria; Tabocchini, Maria Antonella; Campa, Alessandro

    2016-01-01

    We describe a low dose/dose rate gamma irradiation facility (called LIBIS) for in vitro biological systems, for the exposure, inside a CO_2 cell culture incubator, of cells at a dose rate ranging from few μGy/h to some tens of mGy/h. Three different "1"3"7Cs sources are used, depending on the desired dose rate. The sample is irradiated with a gamma ray beam with a dose rate uniformity of at least 92% and a percentage of primary 662 keV photons greater than 80%. LIBIS complies with high safety standards. - Highlights: • A gamma irradiation facility for chronic exposures of cells was set up at the Istituto Superiore di Sanità. • The dose rate uniformity and the percentage of primary 662 keV photons on the sample are greater than 92% and 80%, respectively. • The GEANT4 code was used to design the facility. • Good agreement between simulation and experimental dose rate measurements has been obtained. • The facility will allow to safely investigate different issues about low dose rate effects on cultured cells.

  13. Response of mouse lung to irradiation at different dose-rates

    International Nuclear Information System (INIS)

    Hill, R.P.

    1983-01-01

    Groups of LAF1 mice were given thoracic irradiation using 60 Co γ-rays at dose-rates of 0.05 Gy/min (LDR) or 1.1 Gy/min (HDR) and the death of the animals was monitored as a function of time. It was found that the time pattern of animal deaths was similar for the two different dose-rates. Dose response curves for animals dying at various times up to 500 days after irradiation were calculated and the LD 50 values determined. The curves for the LD 50 values, plotted as a function of the time at analysis for treatment at HDR or LDR, were essentially parallel to each other but separated by a factor (LDR/HDR) of about 1.8. This indicates that the sparing effect of LDR treatment is the same for deaths occurring during the early pneumonitis phase or during the late fibrotic phase of lung damage. The available information on the response of patients to whole thoracic irradiation, given for either palliation or piror to bone marrow transplantation, suggests that for similar dose-rates to those studied here the ratio (LDR/HDR) is only 1.2 to 1.3. This difference between the animal and human data may reflect the modifying effect of the large doses of cytotoxic drugs used in combination with the irradiation of bone marrow transplant patients

  14. Relationship of dose rate and total dose to responses of continuously irradiated beagles

    International Nuclear Information System (INIS)

    Fritz, T.E.; Norris, W.P.; Tolle, D.V.; Seed, T.M.; Poole, C.M.; Lombard, L.S.; Doyle, D.E.

    1978-01-01

    Young-adult beagles were exposed continuously (22 hours/day) to 60 Co γ rays in a specially constructed facility. The exposure rates were either 5, 10, 17, or 35 R/day, and the exposures were terminated at either 600, 1400, 2000, or 4000 R. A total of 354 dogs were irradiated; 221 are still alive as long-term survivors, some after more than 2000 days. The data on survival of these dogs, coupled with data from similar preliminary experiments, allow an estimate of the LD 50 for γ-ray exposures given at a number of exposure rates. They also allow comparison of the relative importance of dose rate and total dose, and the interaction of these two variables, in the early and late effects after protracted irradiation. The LD 50 for the beagle increases from 258 rad delivered at 15 R/minute to approximately 3000 rad at 10 R/day. Over this entire range, the LD 50 is dependent upon hematopoietic damage. At 5 R/day and less, no meaningful LD 50 can be determined; there is nearly normal continued hematopoietic function, survival is prolonged, and the dogs manifest varied individual responses in other organ systems. Although the experiment is not complete, interim data allow several important conclusions. Terminated exposures, while not as effective as radiation continued until death, can produce myelogenous leukemia at the same exposure rate, 10 R/day. More importantly, at the same total accumulated dose, lower exposure rates are more damaging than higher rates on the basis of the rate and degree of hematological recovery that occurs after termination of irradiation. Thus, the rate of hematologic depression, the nadir of the depression, and the rate of recovery are dependent upon exposure rate; the latter is inversely related and the former two are directly related to exposure rate

  15. Effects on the glucose metabolism in type II diabetes model mice treated with dose-rates irradiation

    International Nuclear Information System (INIS)

    Nomura, Takaharu; Sakai, Kazuo

    2004-01-01

    The effects of low-dose rate gamma-irradiation on the type II diabetes mellitus were investigated in C57BL/KsJ-ab/db (db mouse). This mouse develops the type II diabetes within 8 weeks of the birth due to a dysfunction of the insulin receptors. As a result the db mouse shows obese and exhibits hyperinsulinism. Ten-week old female mice (12 mice in each group) were irradiated with gamma-rays at 0.35 mGy/hr, 0.65 mGy/hr or 1.2 mGy/hr in the low-dose rate irradiation facility in the Low Dose Radiation Research Center. The level of plasma glucose and insulin was measured. After 2 weeks irradiation, the glucose level slightly increased, however the difference between the irradiated mice and non-irradiated groups was not significant. The plasma insulin concentration decreased in the non-irradiated group to half of the initial level. In the irradiated group, it also decreased but in the group of 0.65 mGy/hr and 0.35 mGy/hr, it was significantly differed from that in the non-irradiated group. In the glucose tolerance test, plasma glucose level increased shortly after 0.1 mg/head glucose injection by mouth and reached to a peak at 90-120 min after the injection. The glucose level of the non-irradiated mice was slightly higher than that of irradiated mice. The plasma insulin level of non-irradiated group was enhanced after the injection and maintained the level during the test. However the levels of irradiated mice were decreased at 30-60 min after the injection. Both the level of non-irradiated an irradiated was almost same but the non-irradiated one was a little high. In all of mice, the plasma insulin level was highly elevated right after the 0.05 units/head insulin injection by i.p. and the levels were also gradually decreased. The level of the non-irradiated group was slowly decreased and was higher than the irradiated mice. The plasma glucose levels of all mice did not change after the test; however, the levels of irradiated mice were slightly lower than that of non-irradiated

  16. High dose rate (HDR) and low dose rate (LDR) interstitial irradiation (IRT) of the rat spinal cord

    International Nuclear Information System (INIS)

    Pop, Lucas A.M.; Plas, Mirjam van der; Skwarchuk, Mark W.; Hanssen, Alex E.J.; Kogel, Albert J. van der

    1997-01-01

    Purpose: To describe a newly developed technique to study radiation tolerance of rat spinal cord to continuous interstitial irradiation (IRT) at different dose rates. Material and methods: Two parallel catheters are inserted just laterally on each side of the vertebral bodies from the level of Th 10 to L 4 . These catheters are afterloaded with two 192 Ir wires of 4 cm length each (activity 1-2.3 mCi/cm) for the low dose rate (LDR) IRT or connected to the HDR micro-Selectron for the high dose rate (HDR) IRT. Spinal cord target volume is located at the level of Th 12 -L 2 . Due to the rapid dose fall-off around the implanted sources, a dose inhomogeneity across the spinal cord thickness is obtained in the dorso-ventral direction. Using the 100% reference dose (rate) at the ventral side of the spinal cord to prescribe the dose, experiments have been carried out to obtain complete dose response curves at average dose rates of 0.49, 0.96 and 120 Gy/h. Paralysis of the hind-legs after 5-6 months and histopathological examination of the spinal cord of each irradiated rat are used as experimental endpoints. Results: The histopathological damage seen after irradiation is clearly reflected the inhomogeneous dose distribution around the implanted catheters, with the damage predominantly located in the dorsal tract of the cord or dorsal roots. With each reduction in average dose rate, spinal cord radiation tolerance is significantly increased. When the dose is prescribed at the 100% reference dose rate, the ED 50 (induction of paresis in 50% of the animals) for the HDR-IRT is 17.3 Gy. If the average dose rate is reduced from 120 Gy/h to 0.96 or 0.49 Gy/h, a 2.9- or 4.7-fold increase in the ED 50 values to 50.3 Gy and 80.9 Gy is observed; for the dose prescribed at the 150% reference dose rate (dorsal side of cord) ED 50 values are 26.0, 75.5 and 121.4 Gy, respectively. Using different types of analysis and in dependence of the dose prescription and reference dose rate, the

  17. ORIGINAL ARTICLES Endovascular treatment of cerebral ...

    African Journals Online (AJOL)

    With this in mind we looked at the costs ... of surgical or endovascular disposables. ... surgical versus endovascular treatment were 18 and 6 days .... 329: 527) gives a list of nine risk factors which explain most heart attacks: an abnormal ratio.

  18. Repair of sublethal damage in mammalian cells irradiated at ultrahigh dose rates

    International Nuclear Information System (INIS)

    Gerweck, L.E.; Epp, E.R.; Michaels, H.B.; Ling, C.C.; Peterson, E.C.

    1979-01-01

    The lethal response of asynchronous Chinese hamster ovary (CHO) cells exposed to single and split doses of radiation at conventional or ultrahigh dose rates has been examined to determine whether repair of sublethal damage occurs in cells irradiated at ultrahigh dose rates. The high-intensity irradiations were performed with electrons delivered in single 3-nsec pulses from a 600-kV field emission source under medium-removed, thin-layer conditions. Conventional dose-rate experiments were done under identical thin-layer conditions with 50-kVp x rays, or under full-medium conditions with 280-kVp x rays. Oxygenated cells were irradiated and maintained at 22 to 24 0 C between exposures. Survival did not increase as the time between two doses of pulsed electrons increased from 0 to 4 min, indicating no evidence of fast repair. However, increased survival was observed when 30 to 90 min was allowed to elapse between the split doses. The half-time for maximum repair was approx. = 30 min irrespective of the exposure conditions and radiation modality used. Observed repair ratios increased from approx. = 2 to 4 as the single-dose surviving fraction decreased from 10 -2 to 5 x 10 -4 . Over this survival range the repair ratios, measured at the same value of surviving fraction, were independent of dose rate. The observed repair ratios imply that the shoulder regions of the nonfractionated x-ray and pulsed-electron survival curves were not completely restored between the split doses. However, the fraction of the shoulder restored between split doses of radiation was dose-rate-independent. It is concluded that sublethal damage can be repaired in oxygenated CHO cells irradiated at dose rates of the order of 10 11 rad/sec

  19. Effects of low dose rate irradiation on life span prolongation of human premature-aging syndrome model mice

    International Nuclear Information System (INIS)

    Nomura, Takaharu

    2006-01-01

    We previously showed that Type II diabetes model mice prolonged of their life span by life long low dose rate irradiation. We also found that antioxidant function in variety tissues of some strain of mice were enhancement after low dose/low dose rate irradiation. The prolongation of life span might depend on certain damaged level of reactive oxygen species. We thought the effect of the prolongation was due to the enhancement of the antioxidant activities after irradiation. We investigated whether the enhancement of antioxidant activities after low dose rate irradiation had an effect on life span prolongation. Four-week-old female human premature-aging syndrome model mice, kl/kl (klotho) mice, which the life span of this model mouse is about 65 days, were irradiated with gamma rays at 0.35, 0.70 or 1.2 mGy/hr. The 0.70 mGy/hr-irradiated group remarkably effected on the prolongation of their life span. Some mice of the group were extremely survived for about and more 100 days. Antioxidant activities in the irradiated groups were enhancement by low dose rate irradiation, however the dependence of the dose rates were not clearly difference. These results suggest that the antioxidant activities in this model mouse were enhanced by the low dose rate irradiation, and may make it possible to prolong the life span of this mouse. (author)

  20. Survival of tumor cells after proton irradiation with ultra-high dose rates

    International Nuclear Information System (INIS)

    Auer, Susanne; Hable, Volker; Greubel, Christoph; Drexler, Guido A; Schmid, Thomas E; Belka, Claus; Dollinger, Günther; Friedl, Anna A

    2011-01-01

    Laser acceleration of protons and heavy ions may in the future be used in radiation therapy. Laser-driven particle beams are pulsed and ultra high dose rates of >10 9 Gy s -1 may be achieved. Here we compare the radiobiological effects of pulsed and continuous proton beams. The ion microbeam SNAKE at the Munich tandem accelerator was used to directly compare a pulsed and a continuous 20 MeV proton beam, which delivered a dose of 3 Gy to a HeLa cell monolayer within < 1 ns or 100 ms, respectively. Investigated endpoints were G2 phase cell cycle arrest, apoptosis, and colony formation. At 10 h after pulsed irradiation, the fraction of G2 cells was significantly lower than after irradiation with the continuous beam, while all other endpoints including colony formation were not significantly different. We determined the relative biological effectiveness (RBE) for pulsed and continuous proton beams relative to x-irradiation as 0.91 ± 0.26 and 0.86 ± 0.33 (mean and SD), respectively. At the dose rates investigated here, which are expected to correspond to those in radiation therapy using laser-driven particles, the RBE of the pulsed and the (conventional) continuous irradiation mode do not differ significantly

  1. Quality characteristics of mechanically deboned chicken meat irradiated with different dose rates

    Energy Technology Data Exchange (ETDEWEB)

    Brito, Poliana de Paula; Roque, Claudio Vitor; Fukuma, Henrique Takuji; Gomes, Heliana de Azevedo [Brazilian Nuclear Energy Commission (CNEN-MG), Pocos de Caldas, MG (Brazil)]. E-mails: polibrito@yahoo.com.br; cvroque@cnen.gov.br; htfukuma@cnen.gov.br; hgomes@cnen.gov.br; Cipolli, Katia Maria Vieira Avelar Bittencourt [Sao Paulo Agribusiness Technology Agency (APTA), Monte Alegre do Sul, SP (Brazil). Polo Regional do Leste Paulista]. E-mail: katiacipolli@aptaregional.sp.gov.br; Pereira, Jose Luiz [Campinas State University UNICAMP, Campinas, SP (Brazil). Dept. of Food Sciences]. E-mail: pereira@fea.unicamp.br

    2007-07-01

    Mechanically Deboned Chicken Meat (MDCM) is a low cost raw material used in the production of emulsified prepared food, but presents a favorable medium for development of microorganisms. Several studies were carried out with irradiation of edible goods in order to establish a dose that would be capable of decreasing levels of microorganisms without altering the sensorial and nutritional characteristics of the food. Frozen samples of MDCM with skin were irradiated with doses of 0.0 kGy, 3.0 kGy-4.04 kGy.h{sup -1}, and 3.0- 0.32 kGy.h{sup -1}. Individual lots of irradiated and control samples were evaluated during the 11 day refrigeration period for the following parameters: total count of psychotropic bacteria, substances reactive to Thiobarbituric Acid, sensorial evaluation (irradiated odor, oxidized odor, pink and brown colors). The average values in this period were 4.28 log (CFU.g{sup -1}), 2.32 log (CFU.g{sup -1}), and 1.68 log (CFU.g{sup -1}) for control samples, low and high dose rate, respectively. TBARS average values for control samples, low and high dose rate were 0.38 mg.Mal.kg{sup -1}, 2.89 mg.Mal.kg{sup -1}, and 3.64 mg.Mal.kg{sup -}'1, respectively. A difference between irradiated samples and the control sample was observed. The 3.0 kGy-4.04 kGy.h{sup -1} dose rate was verified as the best condition for MDCM processing through the evaluation of all the variables in the conditions of the present study. (author)

  2. Open surgery versus endovascular approach in treatment of extracranial carotid artery aneurysms.

    Science.gov (United States)

    Ni, Leng; Weng, Huiling; Pu, Zuo; Zheng, Yuehong; Liu, Bao; Ye, Wei; Zeng, Rong; Liu, Changwei

    2018-05-01

    The objective of this study was to investigate and to compare the early and long-term results of open surgery with endovascular intervention in the treatment of extracranial carotid artery aneurysms (ECCAs). A retrospective review of patients diagnosed with ECCAs who underwent open surgical or endovascular treatment from 1997 to 2017 was performed. Clinical characteristics, aneurysm profile, and treatment outcomes were recorded. Early results (open surgery; endovascular repair was performed on 16 patients (33.3%). The 30-day stroke or transient ischemic attack rate was not significantly different between the open group (6.3% [2/32]) and the endovascular group (0% [0/16]; P = .307). Cranial nerve injuries occurred in eight patients in the open group (25%) and in no patient in the endovascular group (0%; P = .029). Median length of stay was significantly longer in the open group than in the endovascular group (20 vs 14 days, respectively; P = .013). Median follow-up was 46 months (range, 0-20 years), and no aneurysm-related death occurred during this period. Overall survival rates at 5 years were 88.7% (standard error [SE], 0.08) in the open group and 91.7% (SE, 0.08) in the endovascular group (P = .319; log-rank, .992). For the same time interval, stroke-free survival rates were 85.2% (SE, 0.10) in the open group and 92.2% (SE, 0.07) in the endovascular group (P = .653; log-rank, .201). One patient (1/28 [3.6%]) in the open group and two patients (2/16 [12.5%]) in the endovascular group underwent endovascular reinterventions because of restenosis during the follow-up period. Reintervention-free survival rates were 90.9% in the open group (SE, 0.09) and 69.2% in the endovascular group (SE, 0.21; P = .082; log-rank, 3.016). In this single-institutional experience, both operative and endovascular interventions for ECCAs provided acceptable early and 5-year results. The endovascular approach had significantly less cranial nerve injury and shorter length of

  3. Growth rate of dislocation loop in Fe-Ni-Cr alloy under Kr+ ion and electron irradiation

    International Nuclear Information System (INIS)

    Kimoto, T.; Allen, C.W.; Rehn, L.E.

    1991-10-01

    In order to examine the effect of irradiating particle species on the growth rate of radiation-induced dislocation loops, a solution-annealed Fe-25Ni-15Cr-0.02C alloy was irradiated at 723 K first by 1.5 MeV Kr + ions for 2520 sec, then by 1.5 MeV Kr + ions and 1.0 MeV electrons simultaneously for 780 sec, and finally by 1.0 MeV electrons for 780 sec with the HVEM-Tandem Facility in Argonne National Laboratory. The calculated damage rate by 1.5 MeV Kr + ions was 5.8 x 10 -4 dpa/s, and that by 1.0 MeV electrons was 1 x 10 -4 dpa/s. The growth rate of a dislocation loop located at the center of the specimen was 7 x 10 -3 nm/s for the Kr + ion irradiation, 4 x 10 -2 nm/s for the simultaneous Kr + and electron irradiation, and (2--3) x 10 -2 nm/s for the electron irradiation. This implies that the electron irradiation is about 19 times more effective in the growth of radiation-induced dislocation loops than the Kr + ion irradiation. The dislocation loop growth rate under the simultaneous Kr + and electron irradiation is higher than the sum of the growth rates under the individual Kr + and electron irradiations. 5 refs., 4 figs

  4. Endovascular Mechanical Thrombectomy in Basilar Artery Occlusion: Initial Experience

    Science.gov (United States)

    Park, Bum-Soo; Kwon, Hyon-Jo; Choi, Seung-Won; Kim, Seon-Hwan; Koh, Hyeon-Song; Youm, Jin-Young; Song, Shi-Hun

    2013-01-01

    Objective This study was conducted to assess the efficacy and safety of endovascular mechanical thrombectomy (EMT) for patients diagnosed with basilar artery (BA) occlusion. Materials and Methods We retrospectively analyzed clinical and imaging data of 16 patients diagnosed with BA occlusion who were treated with endovascular intervention from July 2012 to February 2013. Direct suction using the Penumbra system and thrombus retrieval by the Solitaire stent were the main endovascular techniques used to restore BA flow. The outcomes were evaluated based on rate of angiographic recanalization, rate of improvement of National Institutes of Health Stroke Scale (NIHSS) score, rate of modified Rankin Scale (mRS) at discharge and after 3 months, and rate of cerebral hemorrhagic complications. Successful recanalization was defined as achieving Thrombolysis In Cerebral Infarction (TICI) of II or III. Results Sixteen patients received thrombectomy. The mean age was 67.8 ± 11 years and the mean NIHSS score was 12.3 ± 8.2. Eight patients treated within 6 hours of symptom onset were grouped as A and the other 8 patients treated beyond 6 hours (range, 6-120) were grouped as B. Successful recanalization was met in six patients (75%) for group A and 7 (87.5%) for group B. Favorable outcome occurred in 4 patients (50%) for group A and 5 (62.5%) for group B. Conclusion Our study supports the effectiveness and safety of endovascular mechanical thrombectomy in treating BA occlusion even 6 hours after symptom onset. PMID:24167791

  5. Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

    Science.gov (United States)

    Foster, B. R.

    1975-01-01

    A comparison study was conducted of the effects of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue (white pulp) of the mouse spleen with findings as they relate to the mouse thymus. Experimental techniques employed included autoradiography and specific labeling with tritiated thymidine (TdR-(h-3)). The problem studied involved the mechanism of cell proliferation of lymphoid tissue of the mouse spleen and thymus under the stress of continuous irradiation at a dose rate of 10 roentgens (R) per day for 105 days (15 weeks). The aim was to determine whether or not a steady state or near-steady state of cell population could be established for this period of time, and what compensatory mechanisms of cell population were involved.

  6. Dose rate estimates from irradiated light-water-reactor fuel assemblies in air

    International Nuclear Information System (INIS)

    Lloyd, W.R.; Sheaffer, M.K.; Sutcliffe, W.G.

    1994-01-01

    It is generally considered that irradiated spent fuel is so radioactive (self-protecting) that it can only be moved and processed with specialized equipment and facilities. However, a small, possibly subnational, group acting in secret with no concern for the environment (other than the reduction of signatures) and willing to incur substantial but not lethal radiation doses, could obtain plutonium by stealing and processing irradiated spent fuel that has cooled for several years. In this paper, we estimate the dose rate at various distances and directions from typical pressurized-water reactor (PWR) and boiling-water reactor (BWR) spent-fuel assemblies as a function of cooling time. Our results show that the dose rate is reduced rapidly for the first ten years after exposure in the reactor, and that it is reduced by a factor of ∼10 (from the one year dose rate) after 15 years. Even for fuel that has cooled for 15 years, a lethal dose (LD50) of 450 rem would be received at 1 m from the center of the fuel assembly after several minutes. However, moving from 1 to 5 m reduces the dose rate by over a factor of 10, and moving from 1 to 10 m reduces the dose rate by about a factor of 50. The dose rates 1 m from the top or bottom of the assembly are considerably less (about 10 and 22%, respectively) than 1 m from the center of the assembly, which is the direction of the maximum dose rate

  7. Immunological network activation by low-dose rate irradiation. Analysis of cell populations and cell surface molecules in whole body irradiated mice

    International Nuclear Information System (INIS)

    Ina, Yasuhiro; Sakai, Kazuo

    2003-01-01

    The effects of low-dose rate whole body irradiation on biodefense and immunological systems were investigated using female C57BL/6 (B6) mice. These B6 mice were exposed continuously to γ-rays from a 137 Cs source in the long-term low-dose rate irradiation facility at CRIEPI for 0 - 12 weeks at a dose rate of 0.95 mGy/hr. In the bone marrow, thymus, spleen, lymph nodes, and peripheral blood of the irradiated mice, changes in cell populations and cell surface molecules were examined. The cell surface functional molecules (CD3, CD4, CD8, CD19, CD45R/B220, ICAM-1, Fas, NK-1.1, CXCR4, and CCR5), and activation molecules (THAM, CD28, CD40, CD44H, CD70, B7-1, B7-2, OX-40 antigen, CTLA-4, CD30 ligand, and CD40 ligand) were analyzed by flow cytometry. The percentage of CD4 + T cells and cell surface CD8 molecule expressions on the CD8 + T cells increased significantly to 120-130% after 3 weeks of the irradiation, compared to non-irradiated control mice. On the other hand, the percentage of CD45R/B220 + CD40 + B cells, which is one of the immunological markers of inflammation, infection, tumor, and autoimmune disease, decreased significantly to 80-90% between the 3rd to 5th week of irradiation. There was no significant difference in other cell population rates and cell surface molecule expression. Furthermore, abnormal T cells bearing mutated T cell receptors induced by high-dose rate irradiation were not observed throughout this study. These results suggest that low-dose rate irradiation activates the immunological status of the whole body. (author)

  8. A SIPA-based theory of irradiation creep in the low swelling rate regime

    International Nuclear Information System (INIS)

    Garner, F.A.; Woo, C.H.

    1991-11-01

    A model is presented which describes the major facets of the relationships between irradiation creep, void swelling and applied stress. The increasing degree of anisotropy in distribution of dislocation Burger's vectors with stress level plays a major role in this model. Although bcc metals are known to creep and swell at lower rates than fcc metals, it is predicted that the creep-swelling coupling coefficient is actually larger

  9. Effect of irradiation temperature and strain rate on the mechanical properties of V-4Cr-4Ti irradiated to low doses in fission reactors

    International Nuclear Information System (INIS)

    Zinkle, S.J.; Snead, L.L.; Rowcliffe, A.F.; Alexander, D.J.; Gibson, L.T.

    1998-01-01

    Tensile tests performed on irradiated V-(3-6%)Cr-(3-6%)Ti alloys indicate that pronounced hardening and loss of strain hardening capacity occurs for doses of 0.1--20 dpa at irradiation temperatures below ∼330 C. The amount of radiation hardening decreases rapidly for irradiation temperatures above 400 C, with a concomitant increase in strain hardening capacity. Low-dose (0.1--0.5 dpa) irradiation shifts the dynamic strain aging regime to higher temperatures and lower strain rates compared to unirradiated specimens. Very low fracture toughness values were observed in miniature disk compact specimens irradiated at 200--320 C to ∼1.5--15 dpa and tested at 200 C

  10. Quantitative analysis of biological responses to low dose-rate γ-radiation, including dose, irradiation time, and dose-rate

    International Nuclear Information System (INIS)

    Magae, J.; Furukawa, C.; Kawakami, Y.; Hoshi, Y.; Ogata, H.

    2003-01-01

    Full text: Because biological responses to radiation are complex processes dependent on irradiation time as well as total dose, it is necessary to include dose, dose-rate and irradiation time simultaneously to predict the risk of low dose-rate irradiation. In this study, we analyzed quantitative relationship among dose, irradiation time and dose-rate, using chromosomal breakage and proliferation inhibition of human cells. For evaluation of chromosome breakage we assessed micronuclei induced by radiation. U2OS cells, a human osteosarcoma cell line, were exposed to gamma-ray in irradiation room bearing 50,000 Ci 60 Co. After the irradiation, they were cultured for 24 h in the presence of cytochalasin B to block cytokinesis, cytoplasm and nucleus were stained with DAPI and propidium iodide, and the number of binuclear cells bearing micronuclei was determined by fluorescent microscopy. For proliferation inhibition, cells were cultured for 48 h after the irradiation and [3H] thymidine was pulsed for 4 h before harvesting. Dose-rate in the irradiation room was measured with photoluminescence dosimeter. While irradiation time less than 24 h did not affect dose-response curves for both biological responses, they were remarkably attenuated as exposure time increased to more than 7 days. These biological responses were dependent on dose-rate rather than dose when cells were irradiated for 30 days. Moreover, percentage of micronucleus-forming cells cultured continuously for more than 60 days at the constant dose-rate, was gradually decreased in spite of the total dose accumulation. These results suggest that biological responses at low dose-rate, are remarkably affected by exposure time, that they are dependent on dose-rate rather than total dose in the case of long-term irradiation, and that cells are getting resistant to radiation after the continuous irradiation for 2 months. It is necessary to include effect of irradiation time and dose-rate sufficiently to evaluate risk

  11. Intracavitary irradiation of prostatic carcinoma by a high dose-rate afterloading technique

    Energy Technology Data Exchange (ETDEWEB)

    Odelberg-Johnson, O.; Underskog, I.; Johansson, J.E.; Bernshaw, D.; Sorbe, B.; Persson, J.E. (Oerebro Medical Center Hospital (Sweden). Dept. of Oncology Oerebro Medical Center Hospital (Sweden). Dept. of Urology Oerebro Medical Center Hospital (Sweden). Dept. of Gynecologic Oncology Oerebro Medical Center Hospital (Sweden). Dept. of Radiation Physics)

    1991-01-01

    A high dose-rate ({sup 60}Co) afterloading technique was evaluated in a series of 73 patients with prostatic carcinoma stages I-IV. The intraurethral irradiation was combined with external pelvic radiotherapy. A minimum total dose of 78 Gy was delivered to the target volume. In a subgroup of patients extramustine (Estracyt) was given as adjuvant chemohormonal therapy during irradiation. The median follow-up for the whole group was 63 months. The crude 5-year survival rate was 60% and the corrected survival rate 90%. Survival was related to the tumor grade. Local pelvic recurrences were recorded in 17.8%. 'Viable cells' in posttherapy aspiration biopsy were not associated with tumor recurrences or survival. Four patients (5%) had grade 3 late radiation reactions with urethral structure or bladder fibrosis. Urinary tract infections and prior transurethral resections were not associated with a higher frequency of reactions. Concurrent estramustine therapy seemed to increase the frequency of both acute and chronic radiation reactions. Local control, recurrence, and survival were not affected by chemohormonal therapy. The use of tomography, magnetic resonance, and ultrasound as aids to computerized dosimetry may improve local dose distribution and reduce the irradiated volume. (orig.).

  12. DOSKMF2, Dose Rate Distribution in Co60 Gamma Irradiation Plants

    International Nuclear Information System (INIS)

    Remer, M.

    1988-01-01

    1 - Description of program or function: The DOSKMF2 code calculates dose rate distributions in gamma irradiation facilities with 60 Co sources. It has been developed as a tool for the evaluation of research units for the characterization, modification and optimization as well as for the simulation, planning design and evaluation of pilot and industrial facilities. 2 - Method of solution: The basic model of DOSKMF2 contains the computation of the exposure rate, which is dependent on a system of radiation sources (line and/or point sources) at one point of the radiation field. The geometric conditions are described by two coordinate systems. The first is used to arrange the radiation sources and tubes; the second is used to describe the shielding layers in the form of concentric circles. The build-up factor is approximated by Taylor coefficients, also in the case of multi-layer configurations. Calculations of radiation fields in complex irradiation facilities are made by many organizational variants based on the basic model. The interpretation of the results is supported by some statistical calculations. It is possible to store the calculated dose rate values for further processing. 3 - Restrictions on the complexity of the problem: The DOSKMF2 code is presently limited to 40 irradiation tubes and 10 crossed shielding layers. This can be increased by changing dimension statements and input organization

  13. A comparison study on of tumor cell-killing effects between low-dose-rate β-irradiation of 32P and γ-irradiation of 60Co

    International Nuclear Information System (INIS)

    Feng Huiru; Tian Jiahe; Ding Weimin; Zhang Jinming; Chen Yingmao

    2004-01-01

    The paper is to elucidate radiobiological characteristics and radiobiological mechanism in killing tumor cells with low dose rate β-rays and high dose rate γ-rays. HeLa cells were exposed to low-rate β-irradiation of 32 P or high-dose-rate γ-irradiation of 60 Co. Cell response-patterns were compared between two the types of radiations in terms of their inhibition of cell proliferation and cell cycle blockage, evaluated by trypanblue excluded method and flow cytometry, respectively. Results show that there is a different way in growth inhibition effect on HeLa cells between low-dose-rate irradiation of 32 P and high-dose-rate irradiation of 60 Co γ. In exposure to 32 P, the inhibition of cell proliferation in HeLa cell was a prolong course, whereas and the effect was in a more serious and quick way in 60 Co irradiation. Cell cycle arrest in G 2 phase induced by 32 P was lower and more prolong than that induced by 60 Co. The inhibition effect on tumor cells between the two types of radiations is different. Impaired DNA repair system by continuous low-dose-rate radiation might contribute to the final radiation effect of 32 P

  14. Endovascular treatment of PICA aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Mukonoweshuro, W.; Laitt, R.D.; Hughes, D.G. [Radiology Dept., Greater Manchester Neurosciences Unit, Hope Hospital, Salford, Manchester (United Kingdom)

    2003-03-01

    Endovascular treatment of aneurysms of the posterior inferior cerebellar artery (PICA) avoids manipulation of the brainstem or lower cranial nerves and should therefore carry a lower risk of neurological morbidity than surgical clipping. We reviewed our experience of 23 patients with PICA aneurysms treated by endovascular occlusion with Guglielmi detachable coils and documented their long-term outcome on follow-up. We observed a 28 day procedure-related neurological morbidity of 13% (3/23 patients). One patient suffered permanent neurological complications. There were no procedure-related deaths. None of our patients suffered a re-bleed from their treated aneurysms. Our series shows endovascular treatment of ruptured PICA aneurysms to be safe and effective. (orig.)

  15. MCNPCX calculations of dose rates and spectra in experimental channels of the CTEx irradiating facility

    International Nuclear Information System (INIS)

    Gomes, Renato G.; Rebello, Wilson F.; Vellozo, Sergio O.; Junior, Luis M.; Vital, Helio C.; Rusin, Tiago; Silva, Ademir X.

    2013-01-01

    MCNPX simulations have been performed in order to calculate dose rates as well as spectra along the four experimental channels of the gamma irradiating facility at the Technology Center of the Brazilian Army (CTEx). Safety, operational and research requirements have led to the need to determine both the magnitude and spectra of the leaking gamma fluxes. The CTEx experimental facility is cavity type with a moveable set of 28 horizontally positioned rods, filled with Cesium-137 chloride and doubly encased in stainless steel that yields an approximately plane 42 kCi-source that provides a maximum dose rate of about 1.5 kG/h into two irradiating chambers. The channels are intended for irradiation tests outside facility. They would allow larger samples to be exposed to lower gamma dose rates under controlled conditions. Dose rates have been calculated for several positions inside the channels as well as at their exits. In addition, for purposes related to the safety of operators and personnel, the angles submitted by the exiting beams have also been evaluated as they spread when leaving the channels. All calculations have been performed by using a computational model of the CTEx facility that allows its characteristics and operation to be accurately simulated by using the Monte Carlo Method. Virtual dosimeters filled with Fricke (ferrous sulfate) were modeled and positioned throughout 2 vertical channels (top and bottom) and 2 horizontal ones (front and back) in order to map dose rates and gamma spectrum distributions. The calculations revealed exiting collimated beams in the order of tenths of Grays per minute as compared to the maximum 25 Gy / min dose rate in the irradiator chamber. In addition, the beams leaving the two vertical channels were found to exhibit a widespread cone-shaped distribution with aperture angle ranging around 85 deg. The data calculated in this work are intended for use in the design of optimized experiments (better positioning of samples and

  16. Influence of gamma irradiation, cold storage and pulsing on post harvest life and respiration rate of 'golden gate' cut roses

    International Nuclear Information System (INIS)

    Palanikumar, S.; Vinod Kumar; Bhattacharjee, S.K.; Pal, Madan

    2003-01-01

    Gamma irradiation at 0.025 kGy increased the respiration rate of 'Golden Gate' cut roses. The irradiation followed by cold storage (at 4 deg C) brought down the respiration rate after storage duration of 3 days. The respiration rate was found maximum in the sucrose (3% ) pulsed flowers immediately after pulsing. However, the rate of respiration is decreased in all the treatments. The irradiated flowers recorded lowest amount of respiration at senescence and the vase life was maximum in these flowers. (author)

  17. Influence of helium generation rate and temperature history on mechanical properties of model Fe-Cr-Ni alloys irradiated in FFTF at relatively low displacement rates

    International Nuclear Information System (INIS)

    Hamilton, M.L.; Garner, F.A.; Edwards, D.J.

    1993-01-01

    In agreement with earlier studies conducted at higher displacement rates, evolution of mechanical properties of model Fe-Cr-Ni alloys irradiated at lower displacement rates in the 59 Ni isotopic doping experiment does not appear to be strongly affected by large differences in helium generation rate. This insensitivity to helium/dpa ratio is exhibited during both isothermal and non-isothermal irradiation. The overall behavior of the model alloys used in this study is dominated by the tendency to converge to a saturation strength level that is independent of thermomechanical starting state and helium/dpa ratio, but which is dependent on irradiation temperature and alloy composition

  18. Content Validation and Evaluation of an Endovascular Teamwork Assessment Tool.

    Science.gov (United States)

    Hull, L; Bicknell, C; Patel, K; Vyas, R; Van Herzeele, I; Sevdalis, N; Rudarakanchana, N

    2016-07-01

    To modify, content validate, and evaluate a teamwork assessment tool for use in endovascular surgery. A multistage, multimethod study was conducted. Stage 1 included expert review and modification of the existing Observational Teamwork Assessment for Surgery (OTAS) tool. Stage 2 included identification of additional exemplar behaviours contributing to effective teamwork and enhanced patient safety in endovascular surgery (using real-time observation, focus groups, and semistructured interviews of multidisciplinary teams). Stage 3 included content validation of exemplar behaviours using expert consensus according to established psychometric recommendations and evaluation of structure, content, feasibility, and usability of the Endovascular Observational Teamwork Assessment Tool (Endo-OTAS) by an expert multidisciplinary panel. Stage 4 included final team expert review of exemplars. OTAS core team behaviours were maintained (communication, coordination, cooperation, leadership team monitoring). Of the 114 OTAS behavioural exemplars, 19 were modified, four removed, and 39 additional endovascular-specific behaviours identified. Content validation of these 153 exemplar behaviours showed that 113/153 (73.9%) reached the predetermined Item-Content Validity Index rating for teamwork and/or patient safety. After expert team review, 140/153 (91.5%) exemplars were deemed to warrant inclusion in the tool. More than 90% of the expert panel agreed that Endo-OTAS is an appropriate teamwork assessment tool with observable behaviours. Some concerns were noted about the time required to conduct observations and provide performance feedback. Endo-OTAS is a novel teamwork assessment tool, with evidence for content validity and relevance to endovascular teams. Endo-OTAS enables systematic objective assessment of the quality of team performance during endovascular procedures. Copyright © 2016. Published by Elsevier Ltd.

  19. The Primary Origin of Dose Rate Effects on Microstructural Evolution of Austenitic Alloys During Neutron Irradiation

    International Nuclear Information System (INIS)

    Okita, Taira; Sato, Toshihiko; Sekimura, Naoto; Garner, Francis A.; Greenwood, Lawrence R.

    2002-01-01

    The effect of dose rate on neutron-induced microstructural evolution was experimentally estimated. Solution-annealed austenitic model alloys were irradiated at approximately 400 degrees C with fast neutrons at seven different dose rates that vary more than two orders difference in magnitude, and two different doses were achieved at each dose rate. Both cavity nucleation and growth were found to be enhanced at lower dose rate. The net vacancy flux is calculated from the growth rate of cavities that had already nucleated during the first cycle of irradiation and grown during the second cycle. The net vacancy flux was found to be proportional to (dpa/sec) exp (1/2) up to 28.8 dpa and 8.4 x 10 exp (-7) dpa/sec. This implies that mutual recombination dominates point defect annihilation, in this experiment even though point defect sinks such as cavities and dislocations were well developed. Thus, mutual recombination is thought to be the primary origin of the effect of dose rate on microstructural evolution

  20. Recovery Effect and Life Prolong Effect of Long Term Low-Dose Rate Irradiation on Type II Diabetes Model Mice

    International Nuclear Information System (INIS)

    Nomura, T.; Makino, N.; Oda, T.; Suzuki, I.; Sakai, K

    2004-01-01

    The effects of low-dose rate gamma-irradiation were investigated on model mice for type II diabetes mellitus, C57BL/KsJ-db/db. The mice develop the type II diabetes by 10 weeks of age due to obesity and are characterized by hyperinsulinemia. Female 10-week old mice, a group of 12 mice, were irradiated at 0.65 mGy/hr from 137-Cs (370 GBq). The urine glucose levels of all of the mice were strongly positive at the beginning of the irradiation. In the irradiated group, the decrease in the glucose level was observed in 3 mice. Such recovery from the diabetes was never observed in 12 mice of non-irradiated control group. There is no systematic difference in the change of body weight, food assumption, and amount of drinking water, between the irradiated group and the non-irradiated group or between the recovered mice and the non-recovered mice. The survival was better in the irradiated group: the surviving fraction at the age of 90 weeks was 75% in the irradiated group, while 40% in the non-irradiated. Marked difference was also observed in the appearance of the coat hair, skin, and tail; better condition was kept in the irradiated group. In the irradiated mice mortality was delayed and the healthy appearance was prolonged in the irradiated mice by about 20 ? 30 weeks compared with the non-irradiated mice. These results suggest that the low-dose irradiation modified the condition of the diabetic mice, which lead not only to the recovery of the diabetes, but also to the suppression of the aging process. (Author)

  1. Planning of gamma-fields: forming and checking dose-rate homogeneity in irradiation facilities

    International Nuclear Information System (INIS)

    Stenger, V.; Foldiak, G.; Horvath, Zs.; Naszodi, L.

    1975-01-01

    The optimal geometry of the sources of an 80000-Ci 60 Co irradiation facility was calculated. The array of the sources is suitable for fundamental research and pilot-plant radiosterilization simultaneously. A method was developed to compensate the inhomogeneity of the dose-rate field: it is no worse than that of the continuous large-scale facilities. In five years the activity of the sources decreased by about half; therefore, this recharge became inevitable. Experience proved that with the new source geometry optimalized by calculations a dose-rate of 1.2 +-10% became available with the packages. (author)

  2. Influence of irradiation and radiolysis on the corrosion rates and mechanisms of zirconium alloys

    International Nuclear Information System (INIS)

    Verlet, Romain

    2015-01-01

    The nuclear fuel of pressurized water reactors (PWR) in the form of uranium oxide UO 2 pellets (or MOX) is confined in a zirconium alloy cladding. This cladding is very important because it represents the first containment barrier against the release of fission products generated by the nuclear reaction to the external environment. Corrosion by the primary medium of zirconium alloys, particularly the Zircaloy-4, is one of the factors limiting the reactor residence time of the fuel rods (UO 2 pellets + cladding). To optimize core management and to extend the lifetime of the fuel rods in reactor, new alloys based on zirconium-niobium (M5) have been developed. However, the corrosion mechanisms of these are not completely understood because of the complexity of these materials, corrosion environment and the presence of radiation from the nuclear fuel. Therefore, this thesis specifically addresses the effects of radiolysis and defects induced by irradiation with ions in the matrix metal and the oxide layer on the corrosion rate of Zircaloy-4 and M5. The goal is to separate the influence of radiation damage to the metal, that relating to defects created in the oxide and that linked to radiolysis of the primary medium on the oxidation rate of zirconium alloys in reactor. 1) Regarding effect of irradiation of the metal on the oxidation rate: type dislocation loops appear and increase the oxidation rate of the two alloys. For M5, in addition to the first effect, a precipitation of fines needles of niobium reduced the solid solution of niobium concentration in the metal and ultimately in the oxide, which strongly reduces the oxidation rate of the alloy. 2) Regarding the effect of irradiation of the oxide layer on the oxidation rate: defects generated by the nuclear cascades in the oxide increase the oxidation rate of the two materials. For M5, germination of niobium enriched zones in irradiated oxide also causes a decrease of the niobium concentration in solid solution

  3. de novo'' aneurysms following endovascular procedures

    International Nuclear Information System (INIS)

    Briganti, F.; Cirillo, S.; Caranci, F.; Esposito, F.; Maiuri, F.

    2002-01-01

    Two personal cases of ''de novo'' aneurysms of the anterior communicating artery (ACoA) occurring 9 and 4 years, respectively, after endovascular carotid occlusion are described. A review of the 30 reported cases (including our own two) of ''de novo'' aneurysms after occlusion of the major cerebral vessels has shown some features, including a rather long time interval after the endovascular procedure of up to 20-25 years (average 9.6 years), a preferential ACoA (36.3%) and internal carotid artery-posterior communicating artery (ICA-PCoA) (33.3%) location of the ''de novo'' aneurysms, and a 10% rate of multiple aneurysms. These data are compared with those of the group of reported spontaneous ''de novo'' aneurysms after SAH or previous aneurysm clipping. We agree that the frequency of ''de novo'' aneurysms after major-vessel occlusion (two among ten procedures in our series, or 20%) is higher than commonly reported (0 to 11%). For this reason, we suggest that patients who have been submitted to endovascular major-vessel occlusion be followed up for up to 20-25 years after the procedure, using non-invasive imaging studies such as MR angiography and high-resolution CT angiography. On the other hand, periodic digital angiography has a questionable risk-benefit ratio; it may be used when a ''de novo'' aneurysm is detected or suspected on non-invasive studies. The progressive enlargement of the ACoA after carotid occlusion, as described in our case 1, must be considered a radiological finding of risk for ''de novo'' aneurysm formation. (orig.)

  4. Conditioned instrumental behaviour in the rat: Effects of prenatal irradiation with various low dose-rate doses

    International Nuclear Information System (INIS)

    Klug, H.

    1986-01-01

    4 groups of rats of the Wistar-strain were subjected to γ-irradiation on the 16th day of gestation. 5 rats received 0,6 Gy low dose rate irradiation, 5 animals received 0,9 Gy low dose and 6 high dose irradiation, 3 females were shamirradiated. The male offspring of these 3 irradiation groups and 1 control group were tested for locomotor coordination on parallel bars and in a water maze. The female offspring were used in an operant conditioning test. The locomotor test showed slight impairment of locomotor coordination in those animals irradiated with 0,9 Gy high dose rate. Swimming ability was significantly impaired by irradiation with 0,9 Gy high dose rate. Performance in the operant conditioning task was improved by irradiation with 0,9 Gy both low and high dose rate. The 0,9 Gy high dose rate group learned faster than all the other groups. For the dose of 0,9 Gy a significant dose rate effect could be observed. For the dose of 0,6 Gy a similar tendency was observed, differences between 0,6 Gy high and low dose rate and controls not being significant. (orig./MG) [de

  5. On-Line High Dose-rate Gamma Irradiation Test of the Profibus/DP module

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Choi, Young Soo; Kim, Chang Hoi; Koo, In Soo; Hong, Seok Boong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    The field bus data communication is considered for application in nuclear environments. The nuclear facilities, including nuclear power plants, high radioactivity waste disposals, reprocessing plants and thermonuclear fusion installations can benefit from the unique advantages of the field bus communication network for the smart field instruments and controls. A major problem which arises when dealing with one in these nuclear environments, in special circumstances such as the RCS (reactor coolant system) area, is the presence of high gamma-ray irradiation fields. Radioactive constraints for the DBA(design basis accident) qualification of the RTD transmitter installed in the inside of the RCS pump are typically on the order of 4kGy/h with total doses up to 10kGy. In order to use an industrial field bus communication network as an ad-hoc sensor data link in the vicinity of the RCS area of the nuclear power plant, the robust survivability of these system in such intense gamma-radiation fields therefore needs to be verified. We have conducted high dose-rate (up to 4kGy) gamma irradiation experiments on a profibus/DP communication module. In this paper we describe the evolution of its basic characteristics with high dose-rate gamma irradiation and shortly explain the observed phenomena.

  6. Inverse dose-rate-effects on the expressions of extra-cellular matrix-related genes in low-dose-rate γ-ray irradiated murine cells

    International Nuclear Information System (INIS)

    Sugihara, Takashi; Tanaka, Kimio; Oghiso, Yoichi; Murano, Hayato

    2008-01-01

    Based on the results of previous microarray analyses of murine NIH3T3/PG13Luc cells irradiated with continuous low-dose-rate (LDR) γ-ray or end-high-dose-rate-irradiations (end-HDR) at the end of the LDR-irradiation period, the inverse dose-rate-effects on gene expression levels were observed. To compare differences of the effects between LDR-irradiation and HDR-irradiation, HDR-irradiations at 2 different times, one (ini-HDR) at the same time at the start of LDR-irradiation and the other (end-HDR), were performed. The up-regulated genes were classified into two types, in which one was up-regulated in LDR-, ini-HDR-, and end-HDR irradiation such as Cdkn1a and Ccng1, which were reported as p53-dependent genes, and the other was up-regulated in LDR- and ini-HDR irradiations such as pro-collagen TypeIa2/Colla2, TenascinC/Tnc, and Fibulin5/Fbln5, which were reported as extra-cellular matrix-related (ECM) genes. The time dependent gene expression patterns in LDR-irradiation were also classified into two types, in which one was an early response such as in Cdkn1a and Ccng1 and the other was a delayed response such as the ECM genes which have no linearity to total dose. The protein expression pattern of Cdkn1a increased dose dependently in LDR- and end-HDR-irradiations, but those of p53Ser15/18 and MDM2 in LDR-irradiations were different from end-HDR-irradiations. Furthermore, the gene expression levels of the ECM genes in embryonic fibroblasts from p53-deficient mice were not increased by LDR- and end-HDR-irradiation, so the delayed expressions of the ECM genes seem to be regulated by p53. Consequently, the inverse dose-rate-effects on the expression levels of the ECM genes in LDR- and end-HDR-irradiations may be explained from different time responses by p53 status. (author)

  7. Construct Validity and Reliability of Structured Assessment of endoVascular Expertise in a Simulated Setting

    DEFF Research Database (Denmark)

    Bech, B; Lönn, L; Falkenberg, M

    2011-01-01

    Objectives To study the construct validity and reliability of a novel endovascular global rating scale, Structured Assessment of endoVascular Expertise (SAVE). Design A Clinical, experimental study. Materials Twenty physicians with endovascular experiences ranging from complete novices to highly....... Validity was analysed by correlating experience with performance results. Reliability was analysed according to generalisability theory. Results The mean score on the 29 items of the SAVE scale correlated well with clinical experience (R = 0.84, P ... with clinical experience (R = -0.53, P validity and reliability of assessment with the SAVE scale was high when applied to performances in a simulation setting with advanced realism. No ceiling effect...

  8. Outcomes of Peripheral Endovascular Interventions Based on Hospital Volume: A Mini Review of Published Literature

    Directory of Open Access Journals (Sweden)

    Samir V Patel

    2016-01-01

    Full Text Available Previous literature showed hospital procedural volume is an independent predictor for outcomes of various cardiac procedures. However, very few studies shown similar results for peripheral endovascular interventions especially peripheral atherectomy. Here we are reviewing previously published articles to provide volume-outcome relationship for peripheral atherectomy and angioplasty with or without endovascular stenting. We found higher hospital volume significantly and independently lowers in-hospital mortality, amputation rates, peri-procedural complications, length and cost of hospitalization for peripheral endovascular interventions.

  9. Emergency endovascular management of peripheral artery aneurysms and pseudoaneurysms – a review

    Directory of Open Access Journals (Sweden)

    Gillard Jonathan H

    2008-07-01

    Full Text Available Abstract Endovascular stenting has been successfully employed in the management of aortic aneurysms; however, its use in managing peripheral arterial conditions remains questionable. We review the utility of endovascular technique in the management of peripheral arterial conditions like aneurysms, pseudoaneurysms and arterio-venous fistulas in the emergency setting. Though long term data about graft patency rates is not yet available, the endovascular approach appears to be a useful minimally invasive technique in situations where open repair is either difficult or not feasible.

  10. A theoretical and experimental dose rate study at a multipurpose gamma irradiation facility in Ghana

    International Nuclear Information System (INIS)

    Sackey, Tracey A.

    2015-01-01

    Radiation dose rate monitoring out at the Radiation Technology Centre (RTC) of the Ghana Atomic Energy Commission (GAEC) to establish the safety or otherwise of staff at the occupied areas is presented. The facility operates a rectangular source of Co-60 gamma with an having activity of 27.4kCi as at March 2015 and has 14 workers. The aim of the research was determine by means of practical and theoretical evaluations shielding effectiveness of the irradiation chamber. This was to ensure that occupationally exposed workers are not over exposed or their exposures do not exceed the regulatory limits of 7.5μSv/h or 50mSv per annum. The study included dose rate measurements at controlled areas, evaluation of personnel dose history, comparison of experimental and theoretical values and determination of whether the shielding can support a. 18.5PBq (500kCi) Co-60 source. Practical dose rate measurements when the source was in the irradiation position was carried out using a Thermo Scientific Rad-Eye Gamma Survey Meter in the controlled areas of the facility which included the control room, electric room, deionizer room, on top of the roof of irradiation chamber (specifically above the roof plugs) and the two entrances to the irradiation chamber; the personnel door and the goods door. Background reading was found to be 0.08±0.01μSv/h whilst the average dose rates at the two entrances to the irradiation chamber (i e.,- the personnel door and the goods door) were measured to be 0.090μSv/h and 0.109μSv/h respectively. Practical measurements at the roof plugs produced average values of 0.135μSv/h. A particular point on the roof marked as plug-3 produced a relatively higher dose rate of 8.151μSv/h due probably to leakage along the cable to the drive motor. Measurements in the control room, electrical room and deionizer room had average readings of 0.116μSv/h, 0.089μSv/h and 0.614μSv/h respectively. All these average values were below the regulatory limits of 7.5

  11. Stimulation effects of low dose-rate irradiation on pancreatic antioxidant activity in type II diabetes model mice

    International Nuclear Information System (INIS)

    Nomura, Takaharu; Sakai, Kazuo

    2005-01-01

    The effects of low dose-rate gamma irradiation on the type II diabetes mellitus were investigated in BKS.Cg-+Lepr db /+Lepr db /Jcl (DB mice). Ten-week-old female DB mice (5 mice in each group) were irradiated with gamma ray at 0.35, 0.70, or 1.2 mGy/hr. During the course of the 12 weeks the glucose level slightly increased with little difference between the irradiated and the non-irradiated groups. The plasma insulin concentration decreased within the first 4 weeks in all groups. The level was kept low in the non-irradiated mice; while the insulin level in the irradiated groups showed a tendency to increase. In the 0.70 mGy/hr group the increase was statistically significant after 12 weeks of irradiation. Total activity of SOD, one of antioxidative enzymes, decreased both in non-irradiated and irradiated groups; however the decrease was less in the irradiated groups, especially 0.70 mGy/hr group. In the 0.70 mGy/hr group Mn-SOD activity, one of the components of total SOD activity, increased after 12-week irradiation. A pathological examination of the pancreas revealed that damage to β cells responsible for the secretion of insulin was much less in the 0.70 mGy/hr group compared to that in the non-irradiated group. These results indicated that the low dose-rate irradiation increase the antioxidative capacity in the pancreas to protect β cells from oxidative damage, and the to increase the insulin level. This mechanism would lead the mice to the recovery from the disease and the prolongation of the life span as is demonstrated in our previous report. (author)

  12. Structural and Optical Changes of Poly-Vinylidene Fluoride by Electron Irradiation at High Dose Rate

    International Nuclear Information System (INIS)

    Jaleh, B.; Fakhri, P.; Borhani, M.; Habibi, S.; Noroozi, M.

    2012-01-01

    Poly-vinylidene fluoride films were prepared and irradiated by 10MeV electrons at different doses ranging from 50 to 300kGy with a dose rate of 10kGy/s. The FTIR results indicated that no major phase content change was observed. The optical absorption spectra indicated that the electron irradiation results in shifting of the absorption peak, appearance of a new peak and increasing the band gap (Eg). These changes may be due to the breaking of polymer chains and creation of new defects. The X-ray diffraction analysis of samples indicated that the crystallinity did not show any major changes. Concerning the gel fraction measurements, it was observed that gel fraction increases with increasing the dose, where it is an indication of the formation of cross-linked films.

  13. Gamma spectrometry at OSIRIS. Determination of the power and combustion rate of irradiated fuel elements

    International Nuclear Information System (INIS)

    Destot, M.; Musso, J.F.; Cerles, J.M.

    1975-12-01

    An original gamma spectrometer is available at Saclay near the core of the Osiris reactor. With such a device, it is possible to investigate nuclear fuel elements irradiated at Osiris or originating from power reactors. It is quite possible to build devices based on this principle in nuclear power reactors, more particularly in water reactors. With such a device, it is possible to follow the evolution in space and with time of a large number of fission products, and from there to draw precious conclusions relative to reactor safety (e.g. failed element detection) and to fuel economy (i.e. determination of combustion rate). The general characteristics of the device are given as well as its applications: determination of the mass combustion and of the linear power of an irradiated element. A non-destructive, versatile and fast means of investigation is therefore given by the installation of gamma spectroscopy inside a reactor [fr

  14. Anomalous dose rate effects in gamma irradiated SiGe heterojunction bipolar transistors

    International Nuclear Information System (INIS)

    Banerjee, G.; Niu, G.; Cressler, J.D.; Clark, S.D.; Palmer, M.J.; Ahlgren, D.C.

    1999-01-01

    Low dose rate (LDR) cobalt-60 (0.1 rad(Si)/s) gamma irradiated Silicon Germanium (SiGe) Heterojunction Bipolar Transistors (HBTs) were studied. Comparisons were made with devices irradiated with 300 rad(Si)/s gamma radiation to verify if LDR radiation is a serious radiation hardness assurance (RHA) issue. Almost no LDR degradation was observed in this technology up to 50 krad(Si). The assumption of the presence of two competing mechanisms is justified by experimental results. At low total dose (le20 krad), an anomalous base current decrease was observed which is attributed to self-annealing of deep-level traps to shallower levels. An increase in base current at larger total doses is attributed to radiation induced generation-recombination (G/R) center generation. Experiments on gate-assisted lateral PNP transistors and 2D numerical simulations using MEDICI were used to confirm these assertions

  15. Endovascular treatment of stroke. When and How?

    International Nuclear Information System (INIS)

    Mantatzis, M.

    2012-01-01

    different success rates, until the recently published 'SWIFT' trial render the stent retrievers as the best option until now and establish the use of these devices as the preferred method for the mechanical thrombectomy. The effectiveness of endovascular techniques in acute ischemic stroke has been established in many trials. Clinicians however continue to face many challenges in the selection of the most appropriate approach. In conclusion, while IVT remains the standard of care for the few patients presenting early, interventional techniques can play a significant role in a larger population who present much later, fail to improve with IVT, or who do not meet the inclusion criteria for IVT

  16. In-core flow rate distribution measurement test of the JOYO irradiation core

    International Nuclear Information System (INIS)

    Suzuki, Toshihiro; Isozaki, Kazunori; Suzuki, Soju

    1996-01-01

    A flow rate distribution measurement test was carried out for the JOYO irradiation core (the MK-II core) after the 29th duty cycle operation. The main object of the test is to confirm the proper flow rate distribution at the final phase of the MK-II core. The each flow rate at the outlet of subassemblies was measured by the permanent magnetic flowmeter inserted avail of fuel exchange hole in the rotating plug. This is third test in the MK-II core, after 10 years absence from the final test (1985). Total of 550 subassemblies were exchanged and accumulated reactor operation time reached up to 38,000 hours from the previous test. As a conclusion, it confirmed that the flow rate distribution has been kept suitable in the final phase of the MK-II core. (author)

  17. Post operative high dose rate intravaginal irradiation in endometrial cancer: a safe and effective outpatient treatment

    International Nuclear Information System (INIS)

    Chen, Peter; Gibbons, Susan; Vicini, Frank; Weiner, Sheldon; Dmuchowski, Carl; Mele, Beth; Brabbins, Donald; Jennings, John; Gustafson, Gary; Martinez, Alvaro

    1995-01-01

    Purpose: We reviewed our experience with out patient high dose rate (HDR) intravaginal irradiation given post-operatively in endometrial cancer to assess local control, survival, and toxicity when used alone or in combination with external beam irradiation. Methods and Materials: From (12(88)) to (12(92)), 78 patients underwent TAH/BSO and received post-operative HDR intravaginal irradiation for endometrial cancer. Pathologic stage distribution was IB/IC: 56%, II: 22%, III: 22%. Adjuvant therapy was given in one of three schemes: HDR vaginal radiation alone (6 weekly fractions of 500 cGy prescribed 5 mm from the applicator surface treating the upper 4 cm of the vagina), pelvic irradiation with vaginal HDR (500 cGy x 4 weekly fractions) or whole abdomen/pelvic irradiation (WAPI) with vaginal HDR treatment (500 cGy x 3 weekly fractions). Prior to the first HDR vaginal treatment, a simulation with placement of vaginal apex metallic markers was performed to assure proper positioning of the intravaginal cylinders. Pelvic midline blocking was designed from the HDR intravaginal simulation films. The 55 patients who underwent combined external beam irradiation/brachytherapy received a median dose to the pelvis of 5040 cGy (range 25.2-51.6 Gy), and a median total vaginal dose of 5060 cGy (range 30.0-57.6 Gy). Results: Median follow-up is 37 months (range 6-73 months). Local control (vaginally) is 98.7%. The one vaginal failure was in the distal vagina, outside the treatment volume. All other failures (4) were distant with the vagina controlled [3 intra-abdominal and one bone/intra-abdominal]. For stages I and II, the disease free survival is 92.8%. For stage III the disease free survival is 86.5%. Median overall time to failure is 14.3 months (range 8.5-18.6 months). In terms of acute toxicity, no grade 3-4 acute toxicity of the vagina or bladder was seen. However, 9% acute GI toxicity was encountered. Chronic grade 1-2 toxicities included: vaginal 21.8% (foreshortening and

  18. Virtual reality simulation for the optimization of endovascular procedures: current perspectives.

    Science.gov (United States)

    Rudarakanchana, Nung; Van Herzeele, Isabelle; Desender, Liesbeth; Cheshire, Nicholas J W

    2015-01-01

    Endovascular technologies are rapidly evolving, often requiring coordination and cooperation between clinicians and technicians from diverse specialties. These multidisciplinary interactions lead to challenges that are reflected in the high rate of errors occurring during endovascular procedures. Endovascular virtual reality (VR) simulation has evolved from simple benchtop devices to full physic simulators with advanced haptics and dynamic imaging and physiological controls. The latest developments in this field include the use of fully immersive simulated hybrid angiosuites to train whole endovascular teams in crisis resource management and novel technologies that enable practitioners to build VR simulations based on patient-specific anatomy. As our understanding of the skills, both technical and nontechnical, required for optimal endovascular performance improves, the requisite tools for objective assessment of these skills are being developed and will further enable the use of VR simulation in the training and assessment of endovascular interventionalists and their entire teams. Simulation training that allows deliberate practice without danger to patients may be key to bridging the gap between new endovascular technology and improved patient outcomes.

  19. Effects of irradiation at different dose rates on the onset of type I diabetes in model mice

    International Nuclear Information System (INIS)

    Nomura, Takashi; Sakai, Kazuo

    2003-01-01

    We previously demonstrated that low-dose irradiation (0.5 Gy) increased the level of antioxidants and decreased the level of lipid peroxide in normal mice. We also found that 0.5 Gy-irradiation of NOD mice suppressed the onset of type I diabetes. These results were obtained by the irradiation at high dose rate. The aim of the present study is to examine the effects at the low dose rate. The mice were acutely irradiated with 0.5 Gy of X-rays (300 kVp) at 94.2 Gy/hr at 10, 11, 12, 13 or 14 weeks of age, or chronically irradiated with 0.5 Gy of 137 Cs γ-rays at 0.95 mGy/hr starting at 10,11,12,13 or 14 weeks of age. When irradiated at 12th week with the high dose rate X-rays, the onset of diabetes suppressed, and the increase in the specific activity of superoxide dismutase (SOD) in pancreas was observed. On the other hand, the low dose rate γ-rays delivered from 12th week of age to 14th was less effective in the suppression of the incidence of diabetes than the high dose rate X-rays at the 12-14 weeks of age. Furthermore, the significant increase in pancreatic SOD activity was not observed after the low dose irradiation. Splenic macrophage activities of superoxide generation were not affected by the high dose rate irradiation nor the low dose rate irradiation. (author)

  20. Impacts of low dose rate irradiation on the fertility, fecundity and hatchling survival of Japanese rice fish (medaka, Oryzias latipes)

    International Nuclear Information System (INIS)

    Hinton, T.G.; Coughlin, D.P.; Marsh, L.C.; Yi, Yi; Winn, R.

    2004-01-01

    A renewed international interest in the effects on biota from low dose rate irradiation has recently occurred. Much of that interest is centered on the relevance of previously accepted dose rate guidelines (e.g. 10 mGy d -1 for aquatic biota) suggested by the ICRP and IAEA. All parties concerned seem to agree that additional data are needed on population level impacts from chronic low-level exposures to radionuclides. Using a Low Dose Rate Irradiation Facility (LoDIF), we conducted an experiment on the fecundity, fertility and hatchling survival of Japanese Rice Fish (medaka, Oryzias latipes). Fish were exposed externally to 137 Cs from juvenile through adulthood at mean dose rates of 3.5, 35 and 350 mGy d -1 . Fish were bred at maturity and the following endpoints were examined: 1) the number of eggs produced; 2) the percent of eggs that hatched; and 3) the survival of hatchlings 20-days post hatch. The influence of gender was examined by breeding irradiated males with control females; control males with irradiated females; irradiated males with irradiated females; and control males with control females. The data contribute to our understanding the impacts of low dose rate irradiation. (author)

  1. Computational analysis of the dose rates at JSI TRIGA reactor irradiation facilities.

    Science.gov (United States)

    Ambrožič, K; Žerovnik, G; Snoj, L

    2017-12-01

    The JSI TRIGA Mark II, IJS research reactor is equipped with numerous irradiation positions, where samples can be irradiated by neutrons and γ-rays. Irradiation position selection is based on its properties, such as physical size and accessibility, as well as neutron and γ-ray spectra, flux and dose intensities. This paper presents an overview on the neutron and γ-ray fluxes, spectra and dose intensities calculations using Monte Carlo MCNP software and ENDF/B-VII.0 nuclear data libraries. The dose-rates are presented in terms of ambient dose equivalents, air kerma, and silicon dose equivalent. At full reactor power the neutron ambient dose equivalent ranges from 5.5×10 3 Svh -1 to 6×10 6 Svh -1 , silicon dose equivalent from 6×10 2 Gy/h si to 3×10 5 Gy/h si , and neutron air kerma from 4.3×10 3 Gyh -1 to 2×10 5 Gyh -1 . Ratio of fast (1MeVreactor power from 3.4×10 3 Svh -1 to 3.6×10 5 Svh -1 and γ air kerma range 3.1×10 3 Gyh -1 to 2.9×10 5 Gyh -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Lyoluminescence of irradiated carbohydrates - the role of dissolution rate and oxygen

    International Nuclear Information System (INIS)

    Baugh, P.J.; Laflin, P.

    1980-01-01

    The lyoluminescent emission from γ-irradiated carbohydrates is shown to be strictly controlled by the rate of dissolution of the solid and the availability of oxygen for reaction during dissolution. These effects are explained in terms of oxidation of trapped radicals diffusing from the dissolving carbohydrate which react in an 'active volume' set up at the onset of dissolution at the crystal-water interface. At irradiation doses greater than 82.5 krad for mannose there is a suppression of the emission which results from an incomplete oxidation of the diffusing radicals due to insufficient O 2 in the active volume leading to a reaction involving unoxidised radicals and peroxyl radicals which are believed to be the precursors of the emission. This reaction is suppressed when the oxygen supply to the 'active volume' is increased. This can be achieved by increasing the oxygen content of the injector gas and indirectly by decreasing the solubility of the carbohydrate. Under these conditions the linear dose range of the lyoluminescence response is extended to ca. 330 krad close to the dose at which trapped radicals saturate in the irradiated solid carbohydrate. Although lyoluminescence is a liquid surface-layer effect as expected the generation of the emission is greatly influenced by oxygen present in the injection atmosphere. Quenching of lyoluminescence by adding peroxyl radical quenchers Cu(II) ions and hydroquinone, suggests that the reaction involving these quenchers also occurs in the 'active volume'. The results generally can be interpreted in terms of a diffusion model. (author)

  3. Endovascular therapeutic strategies in ruptured intracranial aneurysms

    International Nuclear Information System (INIS)

    Machi, Paolo; Lobotesis, Kyriakos; Vendrell, Jean Francoise; Riquelme, Carlos; Eker, Omer; Costalat, Vincent; Bonafe, Alain

    2013-01-01

    The aim of the present study was to evaluate endovascular techniques used currently which were not available at the time of ISAT inclusion period, such as balloon remodelling and flow-divertion, in order to assess whether these new technologies have improved the endovascular approach outcomes. We present a review of articles, published in major journals, with the aim to evaluate the efficacy and the safety of coiling with balloon remodelling for the treatment of ruptured aneurysms in comparison to coiling performed without such coadjutant techniques. Furthermore, we reviewed publications reporting on the treatment of ruptured aneurysms in the acute phase with the one of the most recent technologies available nowadays: the flow diverting stent. Looking at the recent literature the results regarding ruptured aneurysms treated with balloon assisted coiling (BAC) have shown an improvement in terms of anatomical results and morbi-mortality rates. Case series of ruptured middle cerebral artery (MCA) aneurysms treated by EVT report results similar to those obtained by surgical clipping. Several articles recently report encouraging results in treating ruptured dissecting and blister aneurysms with flow diverters. Questions regarding the best treatment available for ruptured aneurysms are yet to be answered. Hence there is a need for a subsequent trial aiming to answer these unresolved issues

  4. Impact of anatomical variations of the circle of Willis on the incidence of aneurysms and their recurrence rate following endovascular treatment.

    Science.gov (United States)

    Songsaeng, D; Geibprasert, S; Willinsky, R; Tymianski, M; TerBrugge, K G; Krings, T

    2010-11-01

    To analyse the impact of anatomical variations of the parent arteries on the incidence and recurrence rate following coil embolization of aneurysms of the anterior (AcoA), posterior communicating artery (PcoA) and basilar artery (BA) tip. Two hundred and two (96 AcoA, 67 PcoA, and 29 BA) aneurysms in 200 patients were treated with coil embolization between January 2000 and April 2008. Parent artery variations at each location were classified as: AcoA: A1 aplasia versus hypoplasia versus symmetrical size; PcoA: foetal origin versus medium versus small size, BA: cranial versus caudal versus asymmetrical fusion. The incidence of aneurysms and difference between recurrence rates for each group were recorded on follow-up. AcoA, PcoA, and BA aneurysms were more often associated with embryonically earlier vessel wall dispositions (A1 aplasia, foetal PcoA, asymmetrical fusion). Two of these variations were also associated with aneurysm recurrence following coil embolization: asymmetrical A1 segment (p=0.01), and asymmetrical BA tip (p=0.02). AcoA, PcoA, and BA tip aneurysms tend to occur more often in anatomically variant parent artery dispositions, some of which are related to aneurysm recurrence following coil embolization. This may relate to a more fragile vessel disposition as it is not fully matured or to altered haemodynamics secondary to the anatomical variations. Copyright © 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  5. Impact of anatomical variations of the circle of Willis on the incidence of aneurysms and their recurrence rate following endovascular treatment

    International Nuclear Information System (INIS)

    Songsaeng, D.; Geibprasert, S.; Willinsky, R.; Tymianski, M.; TerBrugge, K.G.; Krings, T.

    2010-01-01

    Aim: To analyse the impact of anatomical variations of the parent arteries on the incidence and recurrence rate following coil embolization of aneurysms of the anterior (AcoA), posterior communicating artery (PcoA) and basilar artery (BA) tip. Methods: Two hundred and two (96 AcoA, 67 PcoA, and 29 BA) aneurysms in 200 patients were treated with coil embolization between January 2000 and April 2008. Parent artery variations at each location were classified as: AcoA: A1 aplasia versus hypoplasia versus symmetrical size; PcoA: foetal origin versus medium versus small size, BA: cranial versus caudal versus asymmetrical fusion. The incidence of aneurysms and difference between recurrence rates for each group were recorded on follow-up. Results: AcoA, PcoA, and BA aneurysms were more often associated with embryonically earlier vessel wall dispositions (A1 aplasia, foetal PcoA, asymmetrical fusion). Two of these variations were also associated with aneurysm recurrence following coil embolization: asymmetrical A1 segment (p = 0.01), and asymmetrical BA tip (p = 0.02). Conclusions: AcoA, PcoA, and BA tip aneurysms tend to occur more often in anatomically variant parent artery dispositions, some of which are related to aneurysm recurrence following coil embolization. This may relate to a more fragile vessel disposition as it is not fully matured or to altered haemodynamics secondary to the anatomical variations.

  6. Impact of anatomical variations of the circle of Willis on the incidence of aneurysms and their recurrence rate following endovascular treatment

    Energy Technology Data Exchange (ETDEWEB)

    Songsaeng, D. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Department of Radiology, Siriraj Hospital, Faculty of Medicine, Mahidol University, Bangkok (Thailand); Geibprasert, S.; Willinsky, R. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Tymianski, M. [Department of Neurosurgery, Toronto Western Hospital, University of Toronto, Toronto (Canada); TerBrugge, K.G. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Krings, T., E-mail: timo.krings@uhn.on.c [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada)

    2010-11-15

    Aim: To analyse the impact of anatomical variations of the parent arteries on the incidence and recurrence rate following coil embolization of aneurysms of the anterior (AcoA), posterior communicating artery (PcoA) and basilar artery (BA) tip. Methods: Two hundred and two (96 AcoA, 67 PcoA, and 29 BA) aneurysms in 200 patients were treated with coil embolization between January 2000 and April 2008. Parent artery variations at each location were classified as: AcoA: A1 aplasia versus hypoplasia versus symmetrical size; PcoA: foetal origin versus medium versus small size, BA: cranial versus caudal versus asymmetrical fusion. The incidence of aneurysms and difference between recurrence rates for each group were recorded on follow-up. Results: AcoA, PcoA, and BA aneurysms were more often associated with embryonically earlier vessel wall dispositions (A1 aplasia, foetal PcoA, asymmetrical fusion). Two of these variations were also associated with aneurysm recurrence following coil embolization: asymmetrical A1 segment (p = 0.01), and asymmetrical BA tip (p = 0.02). Conclusions: AcoA, PcoA, and BA tip aneurysms tend to occur more often in anatomically variant parent artery dispositions, some of which are related to aneurysm recurrence following coil embolization. This may relate to a more fragile vessel disposition as it is not fully matured or to altered haemodynamics secondary to the anatomical variations.

  7. Ameliorative effects of low dose/low dose-rate irradiation on reactive oxygen species-related diseases model mice

    International Nuclear Information System (INIS)

    Nomura, Takaharu

    2008-01-01

    Living organisms have developed complex biological system which protects themselves against environmental radiation, and irradiation with proper dose, dose-rate and irradiation time can stimulate their biological responses against oxidative stress evoked by the irradiation. Because reactive oxygen species are involved in various human diseases, non-toxic low dose/low dose-rate radiation can be utilized for the amelioration of such diseases. In this study, we used mouse experimental models for fatty liver, nephritis, diabetes, and ageing to elucidate the ameliorative effect of low dose/low dose-rate radiation in relation to endogenous antioxidant activity. Single irradiation at 0.5 Gy ameliorates carbon tetrachloride-induced fatty liver. The irradiation increases hepatic anti-oxidative system involving glutathione and glutathione peroxidase, suggesting that endogenous radical scavenger is essential for the ameliorative effect of low dose radiation on carbon tetrachloride-induced fatty liver. Single irradiation at 0.5 Gy ameliorates ferric nitrilotriacetate-induced nephritis. The irradiation increases catalase and decreases superoxide dismutase in kidney. The result suggests that low dose radiation reduced generation of hydroxide radical generation by reducing cellular hydroperoxide level. Single irradiation at 0.5 Gy at 12 week of age ameliorates incidence of type I diabetes in non-obese diabetic (NOD) mice through the suppression of inflammatory activity of splenocytes, and resultant apoptosis of β-cells in pancreas. The irradiation activities of superoxide dismutase and catalase, which coordinately diminish intracellular reactive oxygen species. Continuous irradiation at 0.70 mGy/hr from 10 week of age elongates life span, and suppresses alopecia in type II diabetesmice. The irradiation improved glucose clearance without affecting insulin-resistance, and increased pancreatic catalase activity. The results suggest that continuous low dose-rate irradiation protect

  8. Acute myeloid leukemia induction in CBA/H mice by irradiation with fission neutrons as a function of exposure rate

    International Nuclear Information System (INIS)

    Huiskamp, R.

    1991-01-01

    Radiation-induced acute myeloid leukemia (AML) in male CBA/H mice was used as a model for investigation of the effect of reduced fast fission neutron exposure rates on radiation-induced carcinogenesis. Groups of about 90 male CBA/H mice were irradiated or sham-irradiated at the age of 15-20 weeks. The animals were exposed to 400 mGy fast fission neutrons at exposure rates of 2, 10 or 100 mGy/min. The investigation clearly showed that reducing the exposure rate of high-LET fast fission neutrons had no influence on the incidence of AML or on the survival of the irradiated mice. In contrast, a higher incidence of lymphosarcomas was observed in mice irradiated with higher exposure rates. (orig./MG)

  9. Acute myeloid leukemia induction in CBA/H mice by irradiation with fission neutrons as a function of exposure rate

    Energy Technology Data Exchange (ETDEWEB)

    Huiskamp, R [Stichting Energieonderzoek Centrum Nederland, Petten (Netherlands). Radiobiology and Radio-Ecology Unit

    1991-06-01

    Radiation-induced acute myeloid leukemia (AML) in male CBA/H mice was used as a model for investigation of the effect of reduced fast fission neutron exposure rates on radiation-induced carcinogenesis. Groups of about 90 male CBA/H mice were irradiated or sham-irradiated at the age of 15-20 weeks. The animals were exposed to 400 mGy fast fission neutrons at exposure rates of 2, 10 or 100 mGy/min. The investigation clearly showed that reducing the exposure rate of high-LET fast fission neutrons had no influence on the incidence of AML or on the survival of the irradiated mice. In contrast, a higher incidence of lymphosarcomas was observed in mice irradiated with higher exposure rates. (orig./MG).

  10. Absorbed dose to mice in prolonged irradiation by low-dose rate ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Shiragai, Akihiro [National Inst. of Radiological Sciences, Chiba (Japan); Saitou, Mikio; Kudo, Iwao [and others

    2000-07-01

    In this paper, the dose absorbed by mice was evaluated as a preliminary study of the late effects of prolonged continuous irradiation of mice with low-dose rate ionizing radiation. Eight-week-old male and female SPF C3H/HeN mice in three irradiation rooms were exposed to irradiation at 8000, 400, and 20 mGy, respectively, using a {sup 137}Cs {gamma}-source. Nine racks were arranged in a circle approximately 2.5 m from the source in each room, and 10 cages were arranged on the 4 shelves of each rack. Dose distributions, such as in air at the source level, in the three rooms were estimated by using ionization chambers, and the absorbed dose distributions in the room and relative dose distributions in the cages in relation to the distance of the cage center were examined. The mean abdomen doses of the mice measured by TLD were compared with the absorbed doses in the cages. The absorbed dose distributions showed not only inverse-inverse-square-law behavior with distance from the source, but geometric symmetry in every room. The inherent scattering and absorption in each room are responsible for such behavior and asymmetry. Comparison of relative dose distributions revealed cage positions that are not suitable for experiments with high precision doses, but all positions can be used for prolonged continuous irradiation experiments if the position of the cages is rotated regularly. The mean abdomen doses of the mice were similar in each cage. The mean abdomen doses of the mice and the absorbed doses in a cage were almost the same in all cages. Except for errors concerning the positions of the racks and cages, the uncertainties in the exposure doses were estimated to be about {+-}12% for 8000 mGy group, 17% for 400 mGy group, and 35% for 20 mGy group. (K.H.)

  11. Aging and rate effects of the Multigap RPC studied at the Gamma Irradiation Facility at CERN

    CERN Document Server

    Alici, A; Kim, J; Hatzifotiadou, D; Sun, Y; Valenti, G; Williams, M C S; Yakorev, D; Zichichi, A

    2007-01-01

    The selected device for the ALICE Time-of-Flight array is the Multigap Resistive Plate Chamber (MRPC). Previously we have tested this device at the Gamma Irradiation Facility (GIF) at CERN to evaluate the rate dependence; we have now performed additional tests using the final design of the MRPC and with a gas mixture free of hydrocarbons. We have measured the performance of the MRPC up to an equivalent flux of minimum ionizing muons of 2.5 kHz/cm2. We also present results from an aging test obtained by exposing two MRPC strips to the GIF source for a period of six months.

  12. Endovascular repair of para-anastomotic aortoiliac aneurysms.

    LENUS (Irish Health Repository)

    Tsang, Julian S

    2009-11-01

    The purpose of this study is to evaluate the use of endovascular stent grafts in the treatment of para-anastomotic aneurysms (PAAs) as an alternative to high-risk open surgical repair. We identified all patients with previous open aortic aneurysm repair who underwent infrarenal endovascular aneurysm repair (EVAR) at our institution from June 1998 to April 2007. Patient demographics, previous surgery, and operative complications were recorded. One hundred forty-eight patients underwent EVAR during the study period and 11 patients had previous aortic surgery. Of these 11 redo patients, the mean age was 62 years at initial surgery and 71 years at EVAR. All patients were male. Initial open repair was for rupture in five (45%) patients. The average time between initial and subsequent reintervention was 9 years. All patients were ASA Grade III or IV. Fifty-five percent of the PAAs involved the iliac arteries, 36% the abdominal aorta, and 9% were aortoiliac. Ten patients had endovascular stent-grafts inserted electively, and one patient presented with a contained leak. Aorto-uni-iliac stent-grafts were deployed in seven patients, and bifurcated stent-grafts in four patients. A 100% successful deployment rate was achieved. Perioperative mortality was not seen and one patient needed surgical reintervention to correct an endoleak. Endovascular repair of PAAs is safe and feasible. It is a suitable alternative and has probably now become the treatment of choice in the management of PAAs.

  13. Effect of dose rate of gamma irradiation on biochemical quality and browning of mushrooms Agaricus bisporus

    Science.gov (United States)

    Beaulieu, M.; D'Aprano, G.; Lacroix, M.

    2002-03-01

    In order to enhance the shelf-life of edible mature mushrooms Agaricus bisporus, 2 kGy ionising treatments were applied at two different dose rates: 4.5 kGy/h ( I-) and 32 kGy/h ( I+). Both I+ and I- showed 2 and 4 days shelf-life enhancement compared to the control ( C). Before day 9, no significant difference ( p>0.05) in L* value was detected in irradiated mushrooms. However, after day 9, the highest observed L* value (whiteness) was obtained for the mushrooms irradiated in I-. Analyses of phenolic compounds revealed that mushrooms in I- contained more phenols than I+ and C, the latter containing the lower level of phenols. The polyphenol oxidase (PPO) activities of irradiated mushrooms, analysed via catechol oxidase and dopa oxidase substrates, resulted in being significantly lowered ( p⩽0.05) compared to C, with a further decrease in I+. Analyses of the enzymes indicated that PPO activity was lower in I+, contrasting with its lower phenol concentration. Ionising treatments also increased significantly ( p⩽0.05) the phenylalanine ammonia-lyase (PAL) activity. The observation of mushrooms cellular membranes, by electronic microscopy, revealed a better preserved integrity in I- than in I+. It is thus assumed that the browning effect observed in I+ was caused by both the decompartimentation of vacuolar phenol and by the entry of molecular oxygen into the cell cytoplasm. The synergetic effect of the residual active PPO and the molecular oxygen, in contact with the phenols, allowed an increased oxidation rate and, therefore, a more pronounced browning in I+ than in I-.

  14. Gamma exposure rate estimation in irradiation facilities of nuclear research reactors

    International Nuclear Information System (INIS)

    Daoud, Adrian

    2009-01-01

    There are experimental situations in the nuclear field, in which dose estimations due to energy-dependent radiation fields are required. Nuclear research reactors provide such fields under normal operation or due to radioactive disintegration of fission products and structural materials activation. In such situations, it is necessary to know the exposure rate of gamma radiation the different materials under experimentation are subject to. Detectors of delayed reading are usually used for this purpose. Direct evaluation methods using portable monitors are not always possible, because in some facilities the entrance with such devices is often impracticable and also unsafe. Besides, these devices only provide information of the place where the measurement was performed, but not of temporal and spatial fluctuations the radiation fields could have. In this work a direct evaluation method was developed for the 'in-situ' gamma exposure rate for the irradiation facilities of the RA-1 reactor. This method is also applicable in any similar installation, and may be complemented by delayed evaluations without problem. On the other hand, it is well known that the residual effect of radiation modifies some properties of the organic materials used in reactors, such as density, colour, viscosity, oxidation level, among others. In such cases, a correct dosimetric evaluation enables in service estimation of material duration with preserved properties. This evaluation is for instance useful when applied to lubricating oils for the primary circuit pumps in nuclear power plants, thus minimizing waste generation. In this work the necessary elements required to estimate in-situ time and space integrated dose are also established for a gamma irradiated sample in an irradiation channel of a nuclear facility with zero neutron flux. (author)

  15. Effect of dose rate of gamma irradiation on biochemical quality and browning of mushrooms Agaricus bisporus

    International Nuclear Information System (INIS)

    Beaulieu, M.; D'Aprano, G.; Lacroix, M.

    2002-01-01

    In order to enhance the shelf-life of edible mature mushrooms Agaricus bisporus, 2 kGy ionising treatments were applied at two different dose rates: 4.5 kGy/h (I - ) and 32 kGy/h (I + ). Both I + and I - showed 2 and 4 days shelf-life enhancement compared to the control (C). Before day 9, no significant difference (p>0.05) in L * value was detected in irradiated mushrooms. However, after day 9, the highest observed L * value (whiteness) was obtained for the mushrooms irradiated in I - . Analyses of phenolic compounds revealed that mushrooms in I - contained more phenols than I + and C, the latter containing the lower level of phenols. The polyphenol oxidase (PPO) activities of irradiated mushrooms, analysed via catechol oxidase and dopa oxidase substrates, resulted in being significantly lowered (p≤0.05) compared to C, with a further decrease in I + . Analyses of the enzymes indicated that PPO activity was lower in I + , contrasting with its lower phenol concentration. Ionising treatments also increased significantly (p≤0.05) the phenylalanine ammonia-lyase (PAL) activity. The observation of mushrooms cellular membranes, by electronic microscopy, revealed a better preserved integrity in I - than in I + . It is thus assumed that the browning effect observed in I + was caused by both the decompartimentation of vacuolar phenol and by the entry of molecular oxygen into the cell cytoplasm. The synergetic effect of the residual active PPO and the molecular oxygen, in contact with the phenols, allowed an increased oxidation rate and, therefore, a more pronounced browning in I + than in I -

  16. Endovascular brachytherapy prevents restenosis after femoropopliteal angioplasty: results of the Vienna-3 randomised multicenter study

    International Nuclear Information System (INIS)

    Pokrajac, Boris; Poetter, Richard; Wolfram, Roswitha M.; Budinsky, Alexandra C.; Kirisits, Christian; Lileg, Brigitte; Mendel, Helmuth; Sabeti, Schila; Schmid, Rainer; Minar, Erich

    2005-01-01

    Background and purpose: The aim of the trial was to investigate the effect of Iridium-192 gamma endovascular brachytherapy on reduction of restenosis after femoropopliteal angioplasty. Patients and methods: Between Oct, 1998 and Jul, 2001 a total of 134 patients have been randomized after successful angioplasty to brachytherapy or sham irradiation in a prospective, randomized, multicenter, double blind controlled trial. Patients with de novo lesion of at least 5 cm or recurrent lesion of any length after prior angioplasty have been enrolled. Brachytherapy was performed with 7 F centering catheter. Mean lesion length was 9.1 cm (1.5-25 cm) and mean intervention length 13.6 cm (4-27.5 cm) in brachytherapy cohort. Results: In placebo cohort mean lesion length was 10.3 cm (2-25 cm) and mean intervention length 14.1 cm (2-29 cm). A dose of 18 Gy was prescribed 2 mm from the surface of centering balloons. Analyzed (based on angiography) on intention to treat basis the binary restenosis rate at 12 months was 41.7% (28/67) in brachytherapy cohort and 67.1% (45/67) in placebo cohort (χ 2 test, P 30% residual stenosis after angioplasty) have been 23.4% in the brachytherapy and 53.3% in the placebo group (P<0.05), respectively. The cumulative patency rates after 24 months on intention to treat analysis were 54% in the brachytherapy and 27% in the placebo group (P<0.005). Corresponding data for as treated analysis were 77% in the brachytherapy and 39% in the placebo group (P<0.001). Late thrombosis was not seen. Conclusions: Significant reduction of restenosis rate was obtained with endovascular gamma brachytherapy after femoropopliteal angioplasty

  17. Endovascular treatment of ruptured splenic artery aneurysm

    DEFF Research Database (Denmark)

    Bjerring, Ole Steen

    2008-01-01

    Splenic artery aneurysms (SAA) are traditionally treated surgically, but endovascular techniques are becoming increasingly popular. A 64 year-old male with chest pain and low blood pressure was admitted under suspicion of AMI. A CT scan showed a 56 mm SAA with signs of rupture. The patient...... was treated with endovascular embolisation of the SAA with coils. Blood pressure and haemoglobin levels were stabilized and the patient was discharged. In the case of rupture the treatment of choice seems to be endovascular....

  18. Energy related germination and survival rates of water-imbibed Arabidopsis seeds irradiated with protons

    International Nuclear Information System (INIS)

    Qin, H.L.; Xue, J.M.; Lai, J.N.; Wang, J.Y.; Zhang, W.M.; Miao, Q.; Yan, S.; Zhao, W.J.; He, F.; Gu, H.Y.; Wang, Y.G.

    2006-01-01

    In order to investigate the influence of ion energy on the germination and survival rates, water-imbibed Arabidopsis seeds were irradiated with protons in atmosphere. The ion fluence used in this experiment was in the range of 4 x 10 9 -1 x 10 14 ions/cm 2 . The ion energy is from 1.1 MeV to 6.5 MeV. According to the structure of the seed and TRIM simulation, the ions with the energy of 6.5 MeV can irradiate the shoot apical meristem directly whereas the ions with the energy of 1.1 MeV cannot. The results showed that both the germination and survival rates decrease while increasing the ion fluence, and the fluence-respond curve for each energy has different character. Besides the shoot apical meristem (SAM), which is generally considered as the main radiobiological target, the existence of a secondary target around SAM is proposed in this paper

  19. Elemental redistribution behavior in tellurite glass induced by high repetition rate femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Teng, Yu; Zhou, Jiajia; Khisro, Said Nasir; Zhou, Shifeng; Qiu, Jianrong

    2014-01-01

    Highlights: • Abnormal elements redistribution behavior was observed in tellurite glass. • The refractive index and Raman intensity distribution changed significantly. • The relative glass composition remained unchanged while the glass density changed. • First time report on the abnormal element redistribution behavior in glass. • The glass network structure determines the elemental redistribution behavior. - Abstract: The success in the fabrication of micro-structures in glassy materials using femtosecond laser irradiation has proved its potential applications in the construction of three-dimensional micro-optical components or devices. In this paper, we report the elemental redistribution behavior in tellurite glass after the irradiation of high repetition rate femtosecond laser pulses. The relative glass composition remained unchanged while the glass density changed significantly, which is quite different from previously reported results about the high repetition rate femtosecond laser induced elemental redistribution in silicate glasses. The involved mechanism is discussed with the conclusion that the glass network structure plays the key role to determine the elemental redistribution. This observation not only helps to understand the interaction process of femtosecond laser with glassy materials, but also has potential applications in the fabrication of micro-optical devices

  20. Indoor measurement of photovoltaic device characteristics at varying irradiance, temperature and spectrum for energy rating

    International Nuclear Information System (INIS)

    Bliss, M; Betts, T R; Gottschalg, R

    2010-01-01

    The first three-dimensional performance matrix for use in photovoltaic (PV) energy rating is reported utilizing a novel energy rating solar simulator based on LEDs. Device characteristics are measured indoors at varying irradiance (G), temperature (T) and spectrum (E). This opens the possibility for a more accurate measurement system for energy yield prediction of PV devices, especially for devices with high spectral dependence such as wide bandgap solar cells as they take into account spectral changes in the light. The main aspects of the LED-based solar simulator used are briefly described. A measurement method is developed and detailed in the paper, which takes into account the current imperfections in the achievable spectrum. Measurement results for a crystalline silicon solar cell are used to demonstrate the measurement approach. An uncertainty analysis of the measurement system is given, resulting in an overall absolute uncertainty of 4.3% (coverage factor k = 2) in maximum power measurements at 765 W m −2 irradiance with scope for further improvements

  1. Energy related germination and survival rates of water-imbibed Arabidopsis seeds irradiated with protons

    Energy Technology Data Exchange (ETDEWEB)

    Qin, H.L. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Xue, J.M. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Lai, J.N. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Wang, J.Y. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Zhang, W.M. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Miao, Q. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Yan, S. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Zhao, W.J. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); He, F. [School of Life Science, Peking University, Beijing 100871 (China); Gu, H.Y. [School of Life Science, Peking University, Beijing 100871 (China); Wang, Y.G. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China)]. E-mail: ygwang@pku.edu.cn

    2006-04-15

    In order to investigate the influence of ion energy on the germination and survival rates, water-imbibed Arabidopsis seeds were irradiated with protons in atmosphere. The ion fluence used in this experiment was in the range of 4 x 10{sup 9}-1 x 10{sup 14} ions/cm{sup 2}. The ion energy is from 1.1 MeV to 6.5 MeV. According to the structure of the seed and TRIM simulation, the ions with the energy of 6.5 MeV can irradiate the shoot apical meristem directly whereas the ions with the energy of 1.1 MeV cannot. The results showed that both the germination and survival rates decrease while increasing the ion fluence, and the fluence-respond curve for each energy has different character. Besides the shoot apical meristem (SAM), which is generally considered as the main radiobiological target, the existence of a secondary target around SAM is proposed in this paper.

  2. Carcinoma of Uterine Cervix Treated with High Dose Rate Intracavitary Irradiation : 1. Patterns of Failure

    International Nuclear Information System (INIS)

    Kim, Ok Bae; Choi, Tae Jin; Kim, Jin Hee

    1993-01-01

    226 patients with carcinoma of the uterine cervix treated with curative radiation therapy at the Department of Therapeutic Radiology, Dongsan hospital, Keimyung university, School of medicine, from July, 1988 to May, 1991 were evaluated. The patients with all stages of the disease were included in this study. The maximum and mean follow up durations were 60 and 43 months. The radiation therapy consisted of external irradiation to the whole pelvis (2700 - 4500 cGy) and boost parametrial doses(for a total of 4500 - 6300 cGy) with midline shill(4x10 cm), and combined with intracavitary irradiation irradiation(5700 - 7500 cGy to point A). The distribution of patients according to the stage was as follows: stage IB 37(16.4%), stage IIA 91 (40.3%), Stage IIB 58(25.7%), stage III 32(13.8%), stage IV 8 (3.5%). The overall failure rate was 23.9%(54 patients). The failure rate increased as a function of stage from 13.5% in stage 1B to 15.4% in stage IIA, 25.9% in stage IIB, 46.9% in stage III, and 62.5% in stage IV. The pelvic failure alone were 32 patients and 11 patients were as a components of other failure, and remaining 11 patients had distant metastasis only. Among the 43 patients of locoregional failure, 28 patients were not controlled initially and in other words nearly half of total failures were due to residual tumor. The mean medial paracervical(point A) doses were 6700 cGy in stage IIB, 7200 cGy in stage IIA, 7450 cGy in stage IIB, 7600 cGy in stage III and 8100 cGy in stage IV. The medial paracevical doses showed some correlation with tumor control rate in early stage of disease (stage Ib, IIA), but there were higher central failure rate in advanced stage in spite of higher paracervical doses. In advanced stage, failure were not reduced by simple Increment of paracervical doses. To improve a locoregional control rate in advanced stages, it is necessary to give additional treatment such as concomitant chemoradiation

  3. Calculation of heat rating and burn-up for test fuel pins irradiated in DR 3

    International Nuclear Information System (INIS)

    Bagger, C.; Carlsen, H.; Hansen, K.

    1980-01-01

    A summary of the DR 3 reactor and HP1 rig design is given followed by a detailed description of the calculation procedure for obtaining linear heat rating and burn-up values of fuel pins irradiated in HP1 rigs. The calculations are carried out rather detailed, especially regarding features like end pellet contribution to power as a function of burn-up, gamma heat contributions, and evaluation of local values of heat rating and burn-up. Included in the report is also a description of the fast flux- and cladding temperature calculation techniques currently used. A good agreement between measured and calculated local burn-up values is found. This gives confidence to the detailed treatment of the data. (author)

  4. Molecular characterization of non-thymic lymphomas in mice exposed to continuous low-dose-rate g-ray irradiation

    International Nuclear Information System (INIS)

    Takabatake, T.; Fujikawa, K.; Nakamura, S.; Tanaka, S.; Tanaka, I.; Tanaka-Braga III, I.; Sunaga, Y.; Ichinoche, K.; Sato, F.; Tanaka, K.; Matsumoto, T.

    2004-01-01

    To investigate the effects of continuous low-dose-rate irradiation on life span and neoplasm incidence, SPE B6C3 F1 mice were irradiated with 137Cs-ray at dose-rates of 20, 1 and 0.05 mGy/day with accumulated doses equivalent to 8000, 40 and 20 mGy, respectively. Examination of a total of 3,000 irradiated and 1,000 non-irradiated control mice showed that the life spans of the both sexes irradiated at 20 mGy/day, respectively. Examination of a total of 3,000 irradiated and 1,000 non-irradiated control mice showed that the life spans of the both sexes irradiated at 20 mGy/day were significantly shorter than that of the non-irradiated group. No significant difference in the cause of death and mortality rates was found between the groups. However, non-thymic lymphomas, the most common lethal neoplasm, showed a tendency to develop at an earlier age in mice irradiated with 20 mGy/day, regardless of sex. to obtain clues on the molecular mechanisms underlying the earlier development of non-thymic lymphomas in 20 mGy/day irradiated group, detailed molecular characterizations of non-thymic lymphomas with respect to B-cell or T-cell origin was done by detecting rearrangements in immunoglobulin heavy gene and in T-cell receptor b-and g chain genes by Southem hybridization method. to determine whether the early development of non-thymic lymphomas in 20 mGy/day irradiated group is associated wi the any recurrent chromosomal imbalance such as deletions and amplifications, the genome-wide scanning is also currently in progress by both LOH and array CGH methods. Present data obtained by LOH method show that deletions in parts of chromosomes 11 and 12 were more frequent than in chromosomes 2, 4 and 14 in both the non-irradiated control and 20 mGy/day irradiated groups. this work is supported by grants from Aomori Prefecture, Japan. (Author)

  5. Calculation of dose rate in escape channel of Research Irradiating Facility Army Technology Center using code MCNPX

    International Nuclear Information System (INIS)

    Gomes, Renato G.; Rebello, Wilson F.; Vellozo, Sergio O.; Moreira Junior, Luis; Vital, Helio C.; Rusin, Tiago; Silva, Ademir X.

    2013-01-01

    In order to evaluate new lines of research in the area of irradiation of materials external to the research irradiating facility Army Technology Center (CTEx), it is necessary to study security parameters and magnitude of the dose rates from their channels of escape. The objective was to calculate, with the code MCNPX, dose rates (Gy / min) on the interior and exterior of the four-channel leakage gamma irradiator. The channels were designed to leak radiation on materials properly disposed in the area outside the irradiator larger than the expected volume of irradiation chambers (50 liters). This study aims to assess the magnitude of dose rates within the channels, as well as calculate the angle of beam output range outside the channel for analysis as to its spread, and evaluation of safe conditions of their operators (protection radiological). The computer simulation was performed by distributing virtual dosimeter ferrous sulfate (Fricke) in the longitudinal axis of the vertical drain channels (anterior and posterior) and horizontal (top and bottom). The results showed a collimating the beams irradiated on each of the channels to the outside, with values of the order of tenths of Gy / min as compared to the maximum amount of operation of the irradiator chamber (33 Gy / min). The external beam irradiation in two vertical channels showed a distribution shaped 'trunk pyramid', not collimated, so scattered, opening angle 83 ° in the longitudinal direction and 88 in the transverse direction. Thus, the cases allowed the evaluation of materials for irradiation outside the radiator in terms of the magnitude of the dose rates and positioning of materials, and still be able to take the necessary care in mounting shield for radiation protection by operators, avoiding exposure to ionizing radiation. (author)

  6. Precipitate evolution in low-nickel austenitic stainless steels during neutron irradiation at very low dose rates

    International Nuclear Information System (INIS)

    Isobe, Y.; Sagisaka, M.; Garner, F.; Okita, T.

    2007-01-01

    Full text of publication follows: Not all components of a fusion reactor will be subjected to high atomic displacement rates. Some components outside the plasma containment may experience relatively low displacement rates but data generated under long-term irradiation at low dpa rates is hard to obtain. In another study the neutron-induced microstructural evolution in response to long term irradiation at very low dose rates was studied for a Russian low-nickel austenitic stainless steel that is analogous to AISI 304. The irradiated samples were obtained from an out-of-core anti-crush support column for the BN-600 fast reactor with doses ranging from 1.5 to 22 dpa generated at 3x10 -9 to 4x10 -8 dpa/s. The irradiation temperatures were in a very narrow range of 370-375 deg. C. Microstructural observation showed that in addition to voids and dislocations, an unexpectedly high density of small carbide precipitates was formed that are not usually observed at higher dpa rates in this temperature range. These results required us to ask if such unexpected precipitation was anomalous or was a general feature of low-flux, long-term irradiation. It is shown in this paper that a similar behavior was observed in a western stainless steel, namely AISI 304 stainless steel, irradiated at similar temperatures and dpa rates in the EBR-II fast reactor, indicating that irradiation at low dpa rates for many years leads to a different precipitate microstructure and therefore different associated changes in matrix composition than are generated at higher dpa rates. One consequence of this precipitation is a reduced lattice parameter of the alloy matrix, leading to densification that increases in strength with increasing temperature and dose. A. non-destructive method to evaluate these precipitates is under development and is also discussed in this paper. (authors)

  7. Treatment of carcinoma of uterine cervix with high-dose-rate intracavitary irradiation using Ralstron

    International Nuclear Information System (INIS)

    Suh, C.O.; Kim, G.E.; Loh, J.J.K.

    1988-01-01

    From May 1979 through December 1981, a total of 530 patients with carcinoma of the uterine cervix were treated with radiation therapy with curative intent. Of the 530 patients, 365 were treated with a high-dose-rate remote-controlled afterloading system (RALS) using a cobalt source, and 165 patients received a low dose rate using a radium source. External pelvic irradiation with a total of 40-50 Gy to the whole pelvis followed by intracavitary radiation (ICR) with a total dose of 30-39 Gy in ten to 13 fractions to point A was the treatment protocol. ICR was given three times a week with a dose of 3 Gy per fraction. Five-year actuarial survival rate with high-dose-rate ICR by stage was as follows: stage I:82.7% (N = 19) stage II:69.6% (N = 184), and stage III:52.2% (N = 156). The above results were comparable with those with conventional low-dose-rate ICR treatment, and late complications were far less. The application of high-dose-rate ICR was technically simple and easily performed on an outpatient basis without anesthesia, and the patients tolerated it very well. Radiation exposure to personnel was virtually none as compared with that of low-dose-rate ICR. Within a given period of time, more patients can be treated with high-dose-rate ICR because of the short treatment time. The authors therefore conclude that high-dose-rate ICR is suitable for a cancer center where a large number of patients are to be treated

  8. Tritium breeding and release-rate kinetics from neutron-irradiated lithium oxide

    International Nuclear Information System (INIS)

    Quanci, J.F.

    1989-01-01

    The research encompasses the measurement of the tritium breeding and release-rate kinetics from lithium oxide, a ceramic tritium-breeding material. A thermal extraction apparatus which allows the accurate measurement of the total tritium inventory and release rate from lithium oxide samples under different temperatures, pressures and carrier-gas compositions with an uncertainty not exceeding 3% was developed. The goal of the Lithium Blanket Module program was to determine if advanced computer codes could accurately predict the tritium production in the lithium oxide blanket of a fusion power plant. A fusion blanket module prototype was built and irradiated with a deuterium-tritium fusion-neutron source. The tritium production throughout the module was modeled with the MCNP three dimensional Monte Carlo code and was compared to the assay of the tritium bred in the module. The MCNP code accurately predicted tritium-breeding trends but underestimated the overall tritium breeding by 30%. The release rate of tritium from small grain polycrystalline sintered lithium oxides with a helium carrier gas from 300 to 450 C was found to be controlled by the first order surface desorption of monotritiated water. When small amounts of hydrogen were added to the helium carrier gas, the first order rate constant increased from the isotopic exchange of hydrogen for tritium at the lithium oxide surface occurring in parallel with the first order desorption process. The isotopic-exchange first order rate constant temperature dependence and hydrogen partial pressure dependence were evaluated

  9. Dose rate and dose fractionation studies in total body irradiation of dogs

    International Nuclear Information System (INIS)

    Kolb, H.J.; Netzel, B.; Schaffer, E.; Kolb, H.

    1979-01-01

    Total body irradiation (TBI) with 800-900 rads and allogeneic bone marrow transplantation according to the regimen designated by the Seattle group has induced remissions in patients with otherwise refractory acute leukemias. Relapse of leukemia after bone marrow transplantation remains the major problem, when the Seattle set up of two opposing 60 Co-sources and a low dose rate is used in TBI. Studies in dogs with TBI at various dose rates confirmed observations in mice that gastrointestinal toxicity is unlike toxicity against hemopoietic stem cells and possibly also leukemic stem cells depending on the dose rate. However, following very high single doses (2400 R) and marrow infusion acute gastrointestinal toxicity was not prevented by the lowest dose rate studied (0.5 R/min). Fractionated TBI with fractions of 600 R in addition to 1200 R (1000 rads) permitted the application of total doses up to 300 R followed by marrow infusion without irreversible toxicity. 26 dogs given 2400-3000 R have been observed for presently up to 2 years with regard to delayed radiation toxicity. This toxicity was mild in dogs given single doses at a low dose rate or fractionated TBI. Fractionated TBI is presently evaluated with allogeneic transplants in the dog before being applied to leukemic patients

  10. Endovascular surgery in Marfan syndrome: CON.

    Science.gov (United States)

    Kouchoukos, Nicholas T

    2017-11-01

    The frequency of endovascular stent grafting procedures to treat various conditions of the thoracic aorta has increased dramatically over the past three decades. Stent grafting has been applied on a limited basis in patients with Marfan syndrome and other connective tissue disorders, despite recommendations from current guidelines and expert consensus statements against its use in this setting. A review of publications reporting outcomes after stent grafting of the descending thoracic aorta in Marfan patients with acute or chronic aortic dissection indicates that these procedures can be accomplished with rates of early mortality, stroke and spinal cord ischemic injury that are comparable to those observed in patients who do not have Marfan syndrome. However, the rates of primary treatment failure (principally endoleak), secondary treatment failure, need for open repair and late death among the Marfan patients are substantially higher than those observed in patients without this condition. In addition, the rates of retrograde aortic dissection and development of stent-graft induced new entry (SINE), are also greater among patients with Marfan syndrome. All of these findings argue strongly against the routine use of endovascular grafts in Marfan patients with type B or residual type A dissection. Few data are available to assess the role of endografting in Marfan patients with aneurysmal disease, but the progressive aortic dilatation noted in these patients argues strongly against its use in this setting as well. At present, the available data indicate that there is no justification for elective stent grafting in Marfan patients with aortic dissection or aneurysm. The only reasonable indications for primary aortic stent grafting are in the setting of acute aortic dissection or rupture, where the intervention is considered life-saving and rarely, considering the relatively young age of these patients, where the risk of open operation is considered to be prohibitive.

  11. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A. Joe [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Loo, Billy W., E-mail: BWLoo@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Maxim, Peter G., E-mail: PMaxim@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States)

    2017-01-01

    Purpose: A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, “FLASH”) potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). Methods and Materials: We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Results: Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. Conclusions: We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community.

  12. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator.

    Science.gov (United States)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A Joe; Loo, Billy W; Maxim, Peter G

    2017-01-01

    A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, "FLASH") potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Endovascular interventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Bartels, L W; Bakker, C J G

    2003-01-01

    Minimally invasive interventional radiological procedures, such as balloon angioplasty, stent placement or coiling of aneurysms, play an increasingly important role in the treatment of patients suffering from vascular disease. The non-destructive nature of magnetic resonance imaging (MRI), its ability to combine the acquisition of high quality anatomical images and functional information, such as blood flow velocities, perfusion and diffusion, together with its inherent three dimensionality and tomographic imaging capacities, have been advocated as advantages of using the MRI technique for guidance of endovascular radiological interventions. Within this light, endovascular interventional MRI has emerged as an interesting and promising new branch of interventional radiology. In this review article, the authors will give an overview of the most important issues related to this field. In this context, we will focus on the prerequisites for endovascular interventional MRI to come to maturity. In particular, the various approaches for device tracking that were proposed will be discussed and categorized. Furthermore, dedicated MRI systems, safety and compatibility issues and promising applications that could become clinical practice in the future will be discussed. (topical review)

  14. Thermoluminescence study of X-ray irradiated muscovite mineral under various heating rate

    International Nuclear Information System (INIS)

    Kalita, J.M.; Wary, G.

    2014-01-01

    The thermoluminescence (TL) glow curves of X-ray irradiated micro-grain natural muscovite were recorded within 298–520 K at various linear heating rates (2 K/s, 4 K/s, 6 K/s, 8 K/s and 10 K/s). Natural TL of muscovite was checked, but no significant TL was observed within 298–520 K in any heating rate. Within the heating rate 2–10 K/s only a low temperature distinct peak was observed in the temperature range 348–357 K. The TL parameters such as activation energy, order of kinetic, geometrical symmetry factor and pre-exponential frequency factor were investigated from the glow peak by Peak Shape (PS) method and Computerized Glow Curve Deconvolution (CGCD) technique. At lowest heating rate the glow peak obeys non-first order kinetic and at the highest heating rate it follows the second order kinetic. The variation of peak integrals, peak maximum temperatures, FWHM and activation energy with heating rates were investigated, and the glow curves at higher rates were found to be influenced by the presence of the thermal quenching. The thermal quenching activation energy and pre-exponential factor were calculated and found to be 2.31±0.02 eV and 3.46×10 14 s −1 , respectively. -- Highlights: • Muscovite is a silicate mineral with chemical formula KAl 2 (Si 3 Al)O 10 (OH,F) 2 . • TL of natural and X-ray induced muscovite was studied under various heating rates. • TL parameters were evaluated by Peak Shape and CGCD method. • Thermal quenching parameters (W and C) of muscovite were evaluated

  15. Patterns in neurosurgical adverse events: endovascular neurosurgery.

    Science.gov (United States)

    Wong, Judith M; Ziewacz, John E; Panchmatia, Jaykar R; Bader, Angela M; Pandey, Aditya S; Thompson, B Gregory; Frerichs, Kai; Gawande, Atul A

    2012-11-01

    As part of a project to devise evidence-based safety interventions for specialty surgery, the authors sought to review current evidence in endovascular neurosurgery concerning the frequency of adverse events in practice, their patterns, and current methods of reducing the occurrence of these events. This review represents part of a series of papers written to consolidate information about these events and preventive measures as part of an ongoing effort to ascertain the utility of devising system-wide policies and safety tools to improve neurosurgical practice. Based on a review of the literature, thromboembolic events appeared to be the most common adverse events in endovascular neurosurgery, with a reported incidence ranging from 2% to 61% depending on aneurysm rupture status and mode of detection of the event. Intraprocedural and periprocedural prevention and rescue regimens are advocated to minimize this risk; however, evidence on the optimal use of anticoagulant and antithrombotic agents is limited. Furthermore, it is unknown what proportion of eligible patients receive any prophylactic treatment. Groin-site hematoma is the most common access-related complication. Data from the cardiac literature indicate an overall incidence of 9% to 32%, but data specific to neuroendovascular therapy are scant. Manual compression, compression adjuncts, and closure devices are used with varying rates of success, but no standardized protocols have been tested on a broad scale. Contrast-induced nephropathy is one of the more common causes of hospital-acquired renal insufficiency, with an incidence of 30% in high-risk patients after contrast administration. Evidence from medical fields supports the use of various preventive strategies. Intraprocedural vessel rupture is infrequent, with the reported incidence ranging from 1% to 9%, but it is potentially devastating. Improvements in device technology combined with proper endovascular technique play an important role in reducing

  16. Effects of long-term, low dose rate fission neutron irradiation on the peripheral hematological cells in rats

    International Nuclear Information System (INIS)

    Jiang Dingwen; Lei Chengxiang; Shen Xianrong; Ma Li; Yang Xufang; Peng Wulin; Dai Shourong

    2008-01-01

    Objective: To evaluate the effects of long-term, low dose rate fission neutron irradiation on the peripheral hematological cells in rats. Methods: 96 rats were randomly divided into the control group and the irradiation group with low dose rate fission neutron ( 252 Cf, 0.35 mGy/h) irradiation 20.5 h every day. 8 rats of each group were killed at 14 d, 28 d, 42d, 56d, 70d after irradiation and 35d after the irradiation, and their peripheral hematological cells were tested respectively. Results: Compared with the control group, peripheral blood WBC was reduced significantly at the dose of 0.3Gy and 0.4Gy (P < 0.05), and was reduced remarkably at dose of 0.5Gy (P<0.01) and 35d after stopping irradiation(P<0.01). At dose of 0.2Gy, Peripheral blood RBC was abnormally higher comparing with the control group (P<0.01), accompanying with higher HCT and HGB, which suggests condensed blood. At the other point, RBC tend to become lower, but only at dose 0.5Gy, and the difference is significant comparing with control group(P <0.05). At dose of 0.3Gy, 0.4Gy and 0.5Gy, HCT were significantly lower comparing with control group. Comparing with control group, MCV was higher at 35d after stopping irradiation, and PLT was significantly lower in dose of 0.2Gy. Conclusion: Long-term irradiation with low dose rate fission neutron could significantly reduce peripheral blood WBC, with less effects on RBC and PLT. The reduced WBC could not recover at 35d after stopping irradiation. (authors)

  17. Sensitization of rat 9L gliosarcoma cells to low dose rate irradiation by long duration 41 degrees C hyperthermia.

    Science.gov (United States)

    Armour, E P; Wang, Z H; Corry, P M; Martinez, A

    1991-06-15

    Modification of survival by long duration, 41 degrees C hyperthermia in combination with low dose rate radiation (0.5 Gy/h) was determined in rat 9L gliosarcoma cells. Cells were exposed to radiation in a manner that simulated continuous irradiation at a dose rate relevant to clinical brachytherapy. High dose rate X-irradiation was fractionated in 1.0-Gy fractions at 2-h intervals (FLDRI). Previous studies had demonstrated that 9L cells exposed to FLDRI with these parameters have survival characteristics that are equivalent to continuous low dose rate irradiation. Cells exposed to 41 degrees C throughout FLDRI were sensitized significantly (thermal enhancement ratio of 2.07) compared with cells irradiated at 37 degrees C. Incubation for 24 h at 41 degrees C before and/or after FLDRI at either 37 degrees C or 41 degrees C did not increase the slope of the radiation survival curves but did reduce the shoulder. Similarly, heating at 43 degrees C for 30 or 60 min before and/or after irradiation at 0.5 Gy/h also did not enhance cell sensitivity. Survival of cells after irradiation at high dose rate (60 Gy/h) was independent of the temperature during irradiation. Preheat at 41 degrees C for 24 h did not sensitize cells to high dose rate irradiation by increasing the slope of the survival curve, although a loss of shoulder was observed. Sensitization of cells heated at 43 degrees C for 30 or 60 min before high dose rate irradiation was expressed as classical slope modification. Our results demonstrate that 41 degrees C heating during FLDRI greatly sensitizes cells to radiation-induced killing for exposure durations up to 36 h. Heating 9L cells at 41 degrees C or 43 degrees C adjacent to FLDRI at 0.5 Gy/h resulted in no additional enhancement of terminal sensitivity, although shoulder modification was observed. The sensitization by simultaneous heating described above occurred even though thermotolerance developed during extended incubation at 41 degrees C. These in vitro

  18. Micronucleus formation compared to the survival rate of human melanoma cells after X-ray and neutron irradiation and hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    van Beuningen, D.; Streffer, C.; Bertholdt, G.

    1981-09-01

    After neutron and X-ray irradiation and combined X-ray irradiation and hyperthermia (3 hours, 42/sup 0/C), the survival rate of human melanoma cells was measured by means of the colony formation test and compared to the formation of micronuclei. Neutrons had a stronger effect on the formation of micronuclei than the combination of X-rays and hyperthermia. X-rays had the lowest effect. The dose effect curve showed a break at that dose level at which a reduction of cells was observed in the cultures. A good relation between survival rate and formation of micronuclei was found for the X-ray irradiation, but not for the neutron irradiation and the combined treatment. These observations are discussed. At least for X-rays, the micronucleus test has turned out to be a good screening method for the radiosensitivity of a biologic system.

  19. Low-dose-rate total lymphoid irradiation: a new method of rapid immunosuppression

    International Nuclear Information System (INIS)

    Blum, J.E.; de Silva, S.M.; Rachman, D.B.; Order, S.E.

    1988-01-01

    Total Lymphoid Irradiation (TLI) has been successful in inducing immunosuppression in experimental and clinical applications. However, both the experimental and clinical utility of TLI are hampered by the prolonged treatment courses required (23 days in rats and 30-60 days in humans). Low-dose-rate TLI has the potential of reducing overall treatment time while achieving comparable immunosuppression. This study examines the immunosuppressive activity and treatment toxicity of conventional-dose-rate (23 days) vs low-dose-rate (2-7 days) TLI. Seven groups of Lewis rats were given TLI with 60Co. One group was treated at conventional-dose-rates (80-110 cGy/min) and received 3400 cGy in 17 fractions over 23 days. Six groups were treated at low-dose-rate (7 cGy/min) and received total doses of 800, 1200, 1800, 2400, 3000, and 3400 cGy over 2-7 days. Rats treated at conventional-dose-rates over 23 days and at low-dose-rate over 2-7 days tolerated radiation with minimal toxicity. The level of immunosuppression was tested using allogeneic (Brown-Norway) skin graft survival. Control animals retained allogeneic skin grafts for a mean of 14 days (range 8-21 days). Conventional-dose-rate treated animals (3400 cGy in 23 days) kept their grafts 60 days (range 50-66 days) (p less than .001). Low-dose-rate treated rats (800 to 3400 cGy total dose over 2-7 days) also had prolongation of allogeneic graft survival times following TLI with a dose-response curve established. The graft survival time for the 3400 cGy low-dose-rate group (66 days, range 52-78 days) was not significantly different from the 3400 cGy conventional-dose-rate group (p less than 0.10). When the total dose given was equivalent, low-dose-rate TLI demonstrated an advantage of reduced overall treatment time compared to conventional-dose-rate TLI (7 days vs. 23 days) with no increase in toxicity

  20. Changes of some serum proteins in rats continuously irradiated with daily dose rate of 0. 0258 C/kg

    Energy Technology Data Exchange (ETDEWEB)

    Chlebovska, K; Chlebovsky, O; Praslicka, M [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

    1976-01-01

    Changes of serum albumin, haptoglobin, hemopexin and IgG in rats during chronic /sup 60/Co gamma irradiation with a daily dose rate of 0.0258 C/kg within 44 days were investigated by the method of two-dimensional quantitative immunoelectrophoresis. In comparison with normal levels, the values of albumin and IgG in rats during irradiation decreased until the death of animals to 50%, the values of haptoglobin increased till the 39th day of irradiation to 250% and hemopexin values increased to 150%.

  1. Influence of the dose rate on the proliferation capacity of haematopoietic elementary cells in vivo after partial body irradiation

    International Nuclear Information System (INIS)

    Sauer, R.

    1977-01-01

    During direct irradiation of the bone marrow, the dose rate effect was so paradoxical that a temporally protracted exposure has a stronger influence on the proliferation capacity of the elementary cells than one with high dose performance. During the recreation process, the elementary cells proliferated in the sense of a rebound-phaenomenon. This was also referred to the observation that in the non-irradiated bone marrow of animals exposed to partial body irradiation, an activation of the elementary cells started. The results have consequences for the oncological radiotherapy. (orig.) [de

  2. γ irradiation with different dose rates induces different DNA damage responses in Petunia x hybrida cells.

    Science.gov (United States)

    Donà, Mattia; Ventura, Lorenzo; Macovei, Anca; Confalonieri, Massimo; Savio, Monica; Giovannini, Annalisa; Carbonera, Daniela; Balestrazzi, Alma

    2013-05-15

    In plants, there is evidence that different dose rate exposures to gamma (γ) rays can cause different biological effects. The dynamics of DNA damage accumulation and molecular mechanisms that regulate recovery from radiation injury as a function of dose rate are poorly explored. To highlight dose-rate dependent differences in DNA damage, single cell gel electrophoresis was carried out on regenerating Petunia x hybrida leaf discs exposed to LDR (total dose 50 Gy, delivered at 0.33 Gy min(-1)) and HDR (total doses 50 and 100 Gy, delivered at 5.15 Gy min(-1)) γ-ray in the 0-24h time period after treatments. Significant fluctuations of double strand breaks and different repair capacities were observed between treatments in the 0-4h time period following irradiation. Dose-rate-dependent changes in the expression of the PhMT2 and PhAPX genes encoding a type 2 metallothionein and the cytosolic isoform of ascorbate peroxidase, respectively, were detected by Quantitative RealTime-Polymerase Chain Reaction. The PhMT2 and PhAPX genes were significantly up-regulated (3.0- and 0.7-fold) in response to HDR. The results are discussed in light of the potential practical applications of LDR-based treatments in mutation breeding. Copyright © 2013 Elsevier GmbH. All rights reserved.

  3. DNA biosynthesis content and intensiveness in mice thymus at early periods following fast neutron irradiation with different energy rate

    International Nuclear Information System (INIS)

    Indyk, V.M.; Antonenko, G.I.; Parnovskaya, N.V.

    1988-01-01

    Biosynthesis of dna of the thymic glands of animals irradiated by fast neutrons with different energy values in the early post-irradiation period is investigated. It is shown that the rate of mass recovery in organs, their cellular nature, dna content and indices of their specific activity have the dose and time dependences, as well as they considerably differ at different neutron energies and different quality radiation. With the increase of neutron energy value their biological effectiveness decreases

  4. Case of severe intestinal complications caused by high dose-rate intracavitary irradiation for cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Kenji; Nishikawa, Kiyoshi; Matsuki, Kazuhiko; Watanabe, Katsushi

    1987-02-01

    A 46-year-old woman with severe intestinal complication caused by high dose-rate intracavitary irradiation is reported. She received radiation treatment of stage IIb cervical cancer between July 24 and September 26, 1984: a dose of 2400 rad to a point A concurrently with 2000 rad to the parametrium following 4000 rad to the whole pelvis. Eight months later she developed diarrhea and bloody stool. Barium enema study revealed a stenosis at 20 to 25 cm from the anal ring and romanoscopy oozing coagula at the same site. On November 29, 1985 transverse colostomy was performed because of continuing bloody stool and abdominal pain. On January 30, 1986 resection of the ileum and ileostomy were done because of the ileum perforation located 26 cm apart from the ileum end. Some discussion on the causes of this complication are made, suggesting that short length of a tandem and deep location of ovoids influence its cause.

  5. Comparative study of the reciprocal translocation rate in spermatocytes after irradiation of newborn and adult mice

    International Nuclear Information System (INIS)

    Pomerantseva, M.D.

    1978-01-01

    The yield of reciprocal translocations was investigated in spermatocytes of the CBA male mice irradiated immediately after their brith or after the irradiation of the stem spermatogonia at the age of 3 months. The irradiation doses were 100, 200, 400 R X-rays 300 R gamma-rays 60 Co. The yield of translocations in both groups was the same

  6. Gamma irradiation effect and time of storage on the beta-carotene rate of dehydrated parsley

    International Nuclear Information System (INIS)

    Sebastiao, K.I.; Romanelli, M.F.; Leite, Q.R.; Koseki, P.M.; Hamasaki, K.; Villavicencio, A.L.C.H.; Almeida-Muradian, L.B.

    2000-01-01

    The A vitamin is an essential nutrient for men. Therefore, this vitamin or one of its precursors must be ingested for a healthful diet. The carotenoids are also called pro-vitamin A. As any another carotenoid, the β-carotene has a structure with many unsaturations, conferring certain instability. It can be modified and even destroyed for acid, light, heat, oxygen; the formation of cis-trans isomers, reduction of its color and its pro-vitacimin A activity reduction can happen. Those alterations can occur during the processing or storage of the food. The use of the ionizing radiation is a kind of food processing that consists of the use of the high energy of the gamma ray or accelerates electrons, capable to ionize molecules. The carotenoids are considered by literature little sensible to the irradiation. It is suggested doses of 1 to 10 kGy in the irradiation of spices, dehydrated condiments and vegetables. These doses are enough to eliminate or to reduce pathogenic microorganisms and insects, to magnify the time of useful life and still substitute the use of chemical fumigants. They also reveal adequate to the organoleptic aspect, not affecting its flavor and smell. This study had as objective to search the different β-carotene levels in samples of dehydrated parsley submitted to the radiation of 60 Co and stored by 6 months. The results gotten in first analysis had not indicated difference significant statistics in β-carotene rate between the controlled sample and the radiated one. After 6 months of storage, were verified that the β-carotene rate had fallen for the half in both samples

  7. A look into the endovascular crystal ball

    DEFF Research Database (Denmark)

    Schroeder, Torben Veith

    2009-01-01

    This paper summarizes the highlights of the 15th International Workshop of Endovascular Surgery, held in Ajaccio in June 2008. This is an annual event that attracts leading endovascular therapists from both sides of the Atlantic Ocean as well as a contingency from down-under. The layout of this m...

  8. High versus low dose rate intracavitary irradiation for adenocarcinoma of the uterine cervix

    International Nuclear Information System (INIS)

    Kim, Woo-Chul; Loh, John J.K.; Kim, Gwi-Eon; Suh, Chang-Ok

    2001-01-01

    Traditionally, low dose rate (LDR) brachytherapy has been used as a standard modality in the treatment of patients with carcinoma of the uterine cervix. The purpose of this work was to evaluate the effects of high dose rate (HDR) brachytherapy on patients with adenocarcinoma of the uterine cervix and to compare them with the effects of LDR brachytherapy. From January 1971 to December 1992, 104 patients suffering from adenocarcinoma of the uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University. LDR brachytherapy was carried out on 34 patients and HDR brachytherapy on 70 patients. In the LDR group, eight patients were in stage IB, six in IIA, 12 in IIB, three in IIIA and five in IIIB. External radiation therapy was delivered with 10 MV X-rays, 2 Gy fraction per day, total dose of whole pelvis 36-52 Gy (median 46 Gy). LDR radium intracavitary irradiation was performed with a Henschke applicator, 37-59 Gy targeted at point A (median 43 Gy). In the HDR group, there were 16 patients in stage IB, six in IIA, 32 in IIB and 16 in IIIB. The total whole pelvis dose of external radiation was 40-50 Gy (median 44 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with a remotely controlled after-loading system (RALS), 30-48 Gy (median 39 Gy) targeted at point A, three times per week, 3 Gy per fraction. The 5-year overall survival rate in the LDR group was 72.9, 61.9 and 35.7% in stage I, II and III, respectively and the corresponding figures for HDR were 87.1, 58.3 and 43.8% (p 0.05). No prognostic factors were evident in the comparison between the two groups. There was no difference in terms of 5-year survival rate in the patients with adenocarcinoma of the uterine cervix between those treated with HDR and those treated with LDR brachytherapy. Even though late complication rates were higher in the HDR group, most of them were classified as grade I. This retrospective study suggests that HDR

  9. Tritium breeding and release-rate kinetics from neutron-irradiated lithium oxide

    International Nuclear Information System (INIS)

    Quanci, J.F.

    1989-01-01

    The research encompasses the measurement of the tritium breeding and release-rate kinetics from lithium oxide, a ceramic tritium-breeding material. A thermal extraction apparatus which allows the accurate measurement of the total tritium inventory and release rate from lithium oxide samples under different temperatures, pressures and carrier-gas compositions with an uncertainty not exceeding 3% was developed. The goal of the Lithium Blanket Module program was to determine if advanced computer codes could accurately predict the tritium production in the lithium oxide blanket of a fusion power plant. A fusion blanket module prototype, was built and irradiated with a deuterium-tritium fusion-neutron source. The tritium production throughout the module was modeled with the MCNP three dimensional Monte Carlo code and was compared to the assay of the tritium bred in the module. The MCNP code accurately predicted tritium-breeding trends but underestimated the overall tritium breeding by 30%. The release rate of tritium from small grain polycrystalline sintered lithium oxide with a helium carrier gas from 300 to 450 C was found to be controlled by the first order surface desorption of mono-tritiated water. When small amounts of hydrogen were added to the helium carrier gas, the first order rate constant increased from the isotopic exchange of hydrogen for tritium at the lithium oxide surface occurring in parallel with the first order desorption process. The isotopic-exchange first order rate constant temperature dependence and hydrogen partial pressure dependence were evaluated. Large single crystals of lithium oxide were fabricated by the vacuum fusion technique. The release rate of tritium from the large single crystals was found to be controlled by diffusion, and the mixed diffusion-desorption controlled release regime

  10. Effects of low dose rate fission neutron irradiation on the lymphocyte subpopulations of peripheral blood in rats

    International Nuclear Information System (INIS)

    Jiang Dingwen; Lei Chengxiang; Shen Xianrong; Ma Li; Yang Yifang; Peng Wulin; Dai Shourong

    2008-01-01

    Objective: To evaluate the effects of long-term, low dose rate fission neutron irradiation on lymphocyte subpopulations in peripheral blood of rats. Methods: Ninety-six rats were randomly divided into control group and irradiated group exposed to low dose rate fission neutron ( 252 Cf,0.35 mGy/h) for 20.5 h every day. At days 14,28,42,56 and 70 d after irradiation and 35 d after stopping irradiation, After 8 rats of each group were killed, WBC and lymphocyte subpopulations of CD4 + CD3 + , CD8 + CD3 + and CD45RA + /CD161α + in peripheral blood were estimated respectively. Results: Compared with the control group, WBC was reduced significantly at dose of 0.3, 0.4 and 0.5 Gy (P + CD3 - was evidently higher compared with control group at doses of 0.1,0.3, 0.4 and 0.5 Gy and 35 d after stopping irradiation (P + CD3 - was obviously higher compared with control group at dose of 0.2 and 0.3 Gy (P + CD3 + at dose of 0.1 Gy (P + CD3 + at doses of 0.1 and 0.2 Gy (P + CD45RA - ) was increased significantly at doses of 0.2-0.3 Gy, and peripheral blood B cells(CD161α - CD45RA + ) was reduced remarkably at doses of 0.1-0.5 Gy and 35 d after stopping irradiation compared with the control group. Conclusions: Long-term irradiation with low dose rate fission neutron could make TCR (T-cell-receptor) mutant, therefore, WBC, B cells in peripheral blood significantly reduced and NK cells increased. These changes may could not recover at 35 d after Stopping irradiation. (authors)

  11. Postoperative vaginal irradiation by a high dose-rate afterloading technique in endometrial carcinoma stage I

    International Nuclear Information System (INIS)

    Sorbe, B.; Smeds, A.C.

    1989-01-01

    A high dose-rate (cobalt-60) afterloading technique was used for postoperative vaginal irradiation in a series of 404 women with endometrial carcinoma stage I. The total recurrence rate was 3.7% with 0.7% vaginal lesions. The crude 5-year survival rate for the complete series was 91.8% compared to 13.3% for those with recurrences. Depth of myometrical infiltration (>1/3 of the uterine wall) and nuclear grade were the most important prognostic factors. Clinically significant late radiation reactions (bladder and/or rectum) were recorded in 6.9%. The absorbed dose per fraction and the size of the treatment volume were significantly related to the occurrence of both early and late radiation reactions. Vaginal shortening was closely related to the dose per fraction, length of the referce isodose and the applicator diameter. The shape of the vaginal applicator versus the isodose contours and the importance of the source train geometry and relative activity for absorbed dose inhomogeneitis within the treatment volume are discussed. Cumulative radiation effect (CRE) and linear-quadratic (LQ) calculations have been performed and related to tissue reactions within the target volume and in the risk organs. An alpha-beta quotient of 8.8 Gy for vaginal shrinkage effect and 2.0 Gy for late rectal complications are suggested on the basis of calculations using a maximum likelihood method for quantal radiation data. (orig.)

  12. Postoperative vaginal irradiation with high dose rate afterloading technique in endometrial carcinoma stage I

    International Nuclear Information System (INIS)

    Sorbe, B.G.; Smeds, A.C.

    1990-01-01

    A high dose rate ( 60 Co) afterloading technique was used for postoperative prophylactic vaginal irradiation in a series of 404 women with endometrial carcinoma Stage I. The total recurrence rate was 3.7% with 0.7% vaginal deposits. The crude 5-year survival rate for the complete series was 91.8% compared to 13.3% for those with recurrences. Depth of myometrial infiltration (greater than 1/3 of the uterine wall) and nuclear grade were the most important prognostic factors. Clinically significant late radiation reactions (bladder and/or rectum) were recorded in 6.9%. Dose per fraction and the size of the target volume were highly significantly related to the occurrence of both early and late radiation reactions. Vaginal shortening is closely related to the dose per fraction, length of the reference isodose, and the applicator diameter. The shape of the vaginal applicator versus the isodoses and the importance of the source train geometry and relative activity for dose gradient inhomogeneities within the target volume are discussed. Cumulative radiation effect (CRE) and linear-quadratic (LQ) calculations have been performed and related to tissue reactions within the target volume and in the risk organs. An alpha-beta quotient of 8.8 for vaginal shrinkage effect and 2.0 for late rectal complications are suggested on the basis of calculations using a maximum likelihood method for quantal radiation data

  13. Development of computerized dose planning system and applicator for high dose rate remote afterloading irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, T. J. [Keimyung Univ., Taegu (Korea); Kim, S. W. [Fatima Hospital, Taegu (Korea); Kim, O. B.; Lee, H. J.; Won, C. H. [Keimyung Univ., Taegu (Korea); Yoon, S. M. [Dong-a Univ., Pusan (Korea)

    2000-04-01

    To design and fabricate of the high dose rate source and applicators which are tandem, ovoids and colpostat for OB/Gyn brachytherapy includes the computerized dose planning system. Designed the high dose rate Ir-192 source with nuclide atomic power irradiation and investigated the dose characteristics of fabricated brachysource. We performed the effect of self-absorption and determining the gamma constant and output factor and determined the apparent activity of designed source. he automated computer planning system provided the 2D distribution and 3D includes analysis programs. Created the high dose rate source Ir-192, 10 Ci(370GBq). The effective attenuation factor from the self-absorption and source wall was examined to 0.55 of the activity of bare source and this factor is useful for determination of the apparent activity and gamma constant 4.69 Rcm{sup 2}/mCi-hr. Fabricated the colpostat was investigated the dose distributions of frontal, axial and sagittal plane in intra-cavitary radiation therapy for cervical cancer. The reduce dose at bladder and rectum area was found about 20 % of original dose. The computerized brachytherapy planning system provides the 2-dimensional isodose and 3-D include the dose-volume histogram(DVH) with graphic-user-interface mode. emoted afterloading device was built for experiment of created Ir-192 source with film dosimetry within {+-}1 mm discrepancy. 34 refs., 25 figs., 11 tabs. (Author)

  14. High versus low dose-rate intracavitary irradiation for adenocarcinoma of the uterine cervix

    International Nuclear Information System (INIS)

    Kim, Woo Chul; Kim, Gwi Eon; Chung, Eun Ji; Suh, Chang Ok; Hong, Soon Won; Cho, Young Kap; Loh, John Jk

    1999-01-01

    The incidence of adenocarcinoma of the uterine cervix is low. Traditionally, Low Dose Rate (LDR) brachytherapy has been used as a standard modality in the treatment for patients with carcinoma of the uterine cervix. The purpose of this report is to evaluate the effects of the High Dose Rate (HDR) brachytherapy in the patients with adenocarcinoma of the uterine cervix compared with the LDR. From January 1971 to December 1992, 106 patients of adenocarcinoma of uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University with curative intent. LDR brachytherapy was carried out on 35 patients and 71 patients were treated with HDR brachytherapy. In LDR Group, 8 patients were in stage I, 18 in stage II and 9 in stage III. external radiation therapy was delivered with 10 MV X-ray, daily 2 Gy fractionation, total dose 40-46 Gy (median 48 Gy). And LDR Radium intracavitary irradiation was performed with Henschke applicator, 22-56 Gy to point A (median 43 Gy). In HDR Group, there were 16 patients in stage I, 38 in stage II and 17 in stage III. The total dose of external radiation was 40-61 Gy (median 45 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with RALS(Remote Afterloading System), 30-57 Gy (median 39 Gy) to point A, 3 times a week, 3 Gy per fraction. The 5-year overall survival rate in LDR Group was 72.9%, 61.9%, 45.0% in stage I, II, III, respectively and corresponding figures for HDR were 87.1%, 58.3%, 41.2%, respectively (p>0.05). There was no statistical difference in terms of the 5-year overall survival rate between HDR Group and LDR Group in adenocarcinoma of the uterine cervix. There was 11% of late complication rates in LDR Group and 27% in HDR Group. There were no prognostic factors compared HDR with LDR group. The incidence of the late complication rate in HDR Group stage II, III was higher than that in LDR Group (16.7% vs. 31.6% in stage II, 11.1% vs. 35.3% in stage III, p>0

  15. High dose rate interstitial brachytherapy with external beam irradiation for localized prostate cancer. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Hiratsuka, Junichi; Jo, Yoshimasa; Yoden, Eisaku; Tanaka, Hiroyoshi; Imajo, Yoshinari [Kawasaki Medical School, Kurashiki, Okayama (Japan); Nagase, Naomi; Narihiro, Naomasa; Kubota, Juichi

    2000-12-01

    This study was undertaken to assess the biochemical and pathological results of combined external beam radiotherapy and high dose rate Ir-192 brachytherapy (HDR-Ir192) for clinically localized prostate cancer. Between October 1997 and August 1999, 39 evaluable patients with adenocarcinoma of prostate diagnosed by biopsy were treated with interstitial and external beam irradiation. Patients ranged in age from 58-82 years, with a mean of 69.7 years. T1c, T2 and T3 tumors, according to the UICC classification system (1997), were found in 7, 21 and 11 cases respectively. The mean initial pre-treatment PSA was 35.9 ng/ml (median 13.2), with 77% of the patients having had a pre-treatment PSA greater than 10 ng/ml. Of all patients, 17 had received pre-treatment hormonal therapy. Hormonal pretreatment was stopped at the beginning of radiotherapy in all cases. External beam four-field box irradiation was given to the small pelvis to a dose of 45 Gy/25 fractions. Three HDR-Ir192 treatments were given over a 30-h period, with 5.5 Gy per fraction at the circumference of the prostate gland over the course of this study. Biochemical failure was defined as a PSA level >1.5 ng/ml and rising on three consecutive values. If serial post-treatment PSA levels showed a continuous downward trend, failure was not scored. The patient with clinical evidence of progression was classified as a clinical failure. The median follow-up at the time of evaluation was 19.6 months. A post-treatment PSA level {<=}1.0 ng/ml was seen in 26 (67%) patients, and values from >1.0 to {<=}2.0 ng/ml were seen in 10 (26%) patients. Biochemical failure was not seen in 38 patients except for one patient who developed a distant bone metastasis with negative prostatic biopsy 15 months after treatment. Biochemical control rate was 100% (38/38) except for the patient with bone metastasis classified as clinical failure. Negative biopsies 18 months after treatment were found in 93% (14/15) of patients. Only one patient

  16. Endovascular treatment of penetrating arterial trauma with stent grafts.

    Science.gov (United States)

    Biagioni, Rodrigo Bruno; Burihan, Marcelo Calil; Nasser, Felipe; Biagioni, Luisa Ciucci; Ingrund, José Carlos

    2018-02-01

    The endovascular management of arterial injuries has resulted in reduced operating time, blood loss, hospital mortality, lower incidence of sepsis, and decrease in mortality rates. For penetrating trauma, however, the benefits of endovascular therapy are questionable. Data were obtained by retrospective analysis of electronic medical records. All patients with vascular trauma seeking care at our institution from January 2010 to December 2015 were reviewed. A total of 223 vascular trauma patients were enrolled. Of these, 18 patients (8 %) were treated with endovascular techniques. The data related to clinical presentation, patient characteristics, technical aspects of the treatment, and follow-up were analysed. The mean patient age was 35.4 ± 17.8 years, 94 % were male. The mean injury severity score was 10.4 ± 2.5. The most commonly observed trauma mechanism was a gunshot in 10 cases (55 %), followed by lesions provoked by arterial catheter misplacement in five cases (27 %), and stab wounds in three cases (16.6 %). The main injury site was the subclavian artery, accounting for eight cases (44 %), followed by the superficial femoral artery and the tibiofibular trunk in two cases, respectively (18 %). The anterior tibial, fibular artery, axillary, common carotid, superior mesenteric, and profunda femoris were each affected once. Arteriovenous fistula was detected in nine cases (50 %), pseudoaneurysms in nine cases (50 %), and short occlusion in two cases (11 %). The mean follow-up duration was 753 days. The primary patency rate was 92.3 and 61.5 % after one and two years, respectively. The survival rate was 94.4 % after one and two years. Infection of the stents or limb amputations were not identified at follow-up. The endovascular treatment of penetrating arterial injuries with covered stents is feasible. However, the criteria used to choose the best method must be individualized.

  17. A Matched Case-Control Study on Open and Endovascular Treatment of Popliteal Artery Aneurysms.

    Science.gov (United States)

    Dorigo, W; Fargion, A; Masciello, F; Piffaretti, G; Pratesi, G; Giacomelli, E; Pratesi, C

    2018-01-01

    To compare early and late results of open and endovascular management of popliteal artery aneurysm in a retrospective single-center matched case-control study Methods: From 1981 to 2015, 309 consecutive interventions for popliteal artery aneurysm were performed in our institution, in 59 cases with endovascular repair and in 250 cases with open repair. Endovascular repair was preferred in older asymptomatic patients, while open repair was offered more frequently to patients with a thrombosed popliteal artery aneurysm and a poor run-off status. A one-to-one coarsened exact matching on the basis of the baseline demographic, clinical, and anatomical covariates significantly different between the two treatment options was performed and two equivalent groups of 56 endovascular repairs and open repairs were generated. The two groups were compared in terms of perioperative results with χ 2 test and of follow-up outcomes with the Kaplan-Meier curves and log-rank test. There were no differences between the two groups in terms of perioperative outcomes. Median duration of follow-up was 38 months. Five-year survival rates were 94% in endovascular repair group and 89.5% in open repair group (p = 0.4, log-rank 0.6). Primary patency rates at 1, 3, and 5 years were 81%, 78%, and 72% in endovascular repair group and 82.5%, 80%, and 64% in open repair group (p = 0.8, log-rank 0.01). Freedom from reintervention at 5 years was 65.5% in endovascular repair group and 76% in open repair group (p = 0.2, log-rank 1.2). Secondary patency at 1, 3, and 5 years was 94%, 86%, and 74% in endovascular repair group, and 94%, 89%, and 71% in open repair group, respectively (p = 0.9, log-rank 0.01). The rates of limb preservation at 5 years were 94% in endovascular repair group and 86.4% in open repair group (p = 0.3, log-rank 0.8). Open repair and endovascular repair of popliteal artery aneurysms provided in this retrospective single-center experience similar perioperative and follow-up results in

  18. Intravascular ultrasound based dose assessment in endovascular brachytherapy

    International Nuclear Information System (INIS)

    Catalano, Gianpiero; Tamburini, Vittorio; Colombo, Antonio; Nishida, Takahiro; Parisi, Giovanni; Mazzetta, Chiara; Orecchia, Roberto

    2003-01-01

    Background: the role of endovascular brachytherapy in restenosis prevention is well documented. Dose is usually prescribed at a fixed distance from the source axis by angiographic quantification of vessel diameter. Recently, intravascular ultrasound (IVUS) was introduced in dose prescription, allowing a better evaluation of the vessel anatomy. This study retrospectively explores the difference between prescription following angiographic vessel sizing and delivered dose calculated with IVUS. Methods and results: Seventeen lesions were studied with IVUS, identifying on irradiated segment, three sections on which measuring minimal and maximal distance from the centre of IVUS catheter to the adventitia; using dedicated software, corresponding doses were calculated. The dose ranged widely, with maximal and minimal values of 71.6 and 4.9 Gy; furthermore, heterogeneity in dose among different sections was observed. In the central section, the maximal dose was 206% of the one prescribed with the QCA model at 2 mm from the source axis, while the minimal dose was 96%. In proximal and distal sections, respective values were 182, 45, 243, and 122%. Conclusions: Our analysis confirmed the dose inhomogeneity delivered with an angiographic fixed-dose prescription strategy. A dose variation was found along the irradiated segment due to the differences in vessel thickness. IVUS emerged as an important tool in endovascular brachytherapy, especially for irregular-shaped vessels

  19. One-stage surgery in combination with thoracic endovascular grafting and resection of T4 lung cancer invading the thoracic aorta and spine

    OpenAIRE

    Sato, Seijiro; Goto, Tatsuya; Koike, Terumoto; Okamoto, Takeshi; Shoji, Hirokazu; Ohashi, Masayuki; Watanabe, Kei; Tsuchida, Masanori

    2017-01-01

    A novel strategy of one-stage surgery in combination with thoracic endovascular grafting and resection for T4 lung cancer invading the thoracic aorta and spine is described. A 56-year-old man with locally advanced lung cancer infiltrating the aortic wall and spine underwent neoadjuvant chemotherapy and thoracic irradiation, followed by en bloc resection of the aortic wall and spine with thoracic endovascular grafting. He developed postoperative chylothorax, but there were no stent graft-relat...

  20. Clastogenic effects in human lymphocytes exposed to low and high dose rate X-ray irradiation and vitamin C

    International Nuclear Information System (INIS)

    Konopacka, M; Rogolinski, J.

    2011-01-01

    In the present work we investigated the ability of vitamin C to modulate clastogenic effects induced in cultured human lymphocytes by X-irradiation delivered at either high (1 Gy/min) or low dose rate (0.24 Gy/min). Biological effects of the irradiation were estimated by cytokinesis-block micronucleus assay including the analysis of the frequency of micronuclei (MN) and apoptotic cells as well as calculation of nuclear division index (NDI). The numbers of micronucleated binucleate lymphocytes (MN-CBL) were 24.85 ± 2.67% and 32.56 ± 3.17% in cultures exposed to X-rays (2 Gy) delivered at low and high dose rates, respectively. Addition of vitamin C (1-20 μg/ml) to the medium of cultures irradiated with the low dose rate reduced the frequency of micronucleated lymphocytes with multiple MN in a concentration-dependent manner. Lymphocytes exposed to the high dose rate radiation showed a U-shape response: low concentration of vitamin C significantly reduced the number of MN, whereas high concentration influenced the radiation-induced total number of micronucleated cells insignificantly, although it increased the number of cells with multiple MN. Addition of vitamin C significantly reduced the fraction of apoptotic cells, irrespective of the X-ray dose rate. These results indicate that radiation dose rate is an important exposure factor, not only in terms of biological cell response to irradiation, but also with respect to the modulating effects of antioxidants. (authors)

  1. Effects of keV electron irradiation on the avalanche-electron generation rates of three donors on oxidized silicon

    International Nuclear Information System (INIS)

    Sah, C.; Sun, J.Y.; Tzou, J.J.

    1983-01-01

    After keV electron beam irradiation of oxidized silicon, the avalanche-electron-injection generation rates and densities of the bulk compensating donor, the interface states, and the turnaround trap all increase. Heating at 200 0 C can anneal out these three donor-like traps, however, it cannot restore the generation rates back to their original and lower pre-keV electron irradiation values. The experimental results also indicate that all three traps may be related to the same mobile impurity species whose bonds are loosened by the keV electrons and then broken or released by the avalanche injected electrons

  2. Rabbit models of cerebral vasospasm established with endovascular puncture

    International Nuclear Information System (INIS)

    Tu Jianfei; Liu Yizhi; Ji Jiansong; Zhao Zhongwei

    2008-01-01

    Objective: To investigate the method of endovascular puncture to establish rabbit models of cerebral vasospasm. Methods: New Zealand white rabbits were divided into 5 groups (12 h, 1 d, 2 d, 3 d and 7 d) randomly, and each group was separated into subarachnoid hemorrhage (SAH) subgroup (n=5) and control subgroup (n=2). cerebral vascular spasm (CVS) models were established after SAH with endovascular puncture. CT scans before and after operation were performed. The internal diameters and the wall thicknesses of posterior communicans artery (PcoA) and basilar artery (BA) were measured with HE stain after the animals were executed. Results: CVS model was successfully eastblished in 35 rabbits (SAH subgroup 25, control subgroup 10), resulting a successful rate of 48.61%. Compared with control subgroup, PcoA and BA showed shrinkage of internal diameters of 43.60% and 51.82% 12 h after SAH, respectively, and the shrinkage appeared as biphasic patterns until the 7th study day with another peaks of 29.32% and 45.19%, respectively. Conclusions: Endovascular puncture is an effective method to establish rabbit of CVS. The death rate of animals can be decreased with the asage of new interventional material and perfection for the details of operation. (authors)

  3. A new cerebral vasospasm model established with endovascular puncture technique

    International Nuclear Information System (INIS)

    Tu Jianfei; Liu Yizhi; Ji Jiansong; Zhao Zhongwei

    2011-01-01

    Objective: To investigate the method of establishing cerebral vasospasm (CVS) models in rabbits by using endovascular puncture technique. Methods: Endovascular puncture procedure was performed in 78 New Zealand white rabbits to produce subarachnoid hemorrhage (SAH). The survival rabbits were randomly divided into seven groups (3 h, 12 h, 1 d, 2 d, 3 d, 7 d and 14 d), with five rabbits in each group for both study group (SAH group) and control group. Cerebral CT scanning was carried out in all rabbits both before and after the operation. The inner diameter and the thickness of vascular wall of both posterior communicating artery (PcoA) and basilar artery (BA) were determined after the animals were sacrificed, and the results were analyzed. Results: Of 78 experimental rabbits, CVS model was successfully established in 45, including 35 of SAH group and 10 control subgroup. The technical success rate was 57.7%. Twelve hours after the procedure, the inner diameter of PcoA and BA in SAH group was decreased by 45.6% and 52.3%, respectively, when compared with these in control group. The vascular narrowing showed biphasic changes, the inner diameter markedly decreased again at the 7th day when the decrease reached its peak to 31.2% and 48.6%, respectively. Conclusion: Endovascular puncture technique is an effective method to establish CVS models in rabbits. The death rate of experimental animals can be decreased if new interventional material is used and the manipulation is carefully performed. (authors)

  4. Transatlantic Multispecialty Consensus on Fundamental Endovascular Skills: Results of a Delphi Consensus Study.

    Science.gov (United States)

    Maertens, H; Aggarwal, R; Macdonald, S; Vermassen, F; Van Herzeele, I

    2016-01-01

    The aim of this study was to establish a consensus on Fundamental Endovascular Skills (FES) for educational purposes and development of training curricula for endovascular procedures. The term "Fundamental Endovascular Skills" is widely used; however, the current literature does not explicitly describe what skills are included in this concept. Endovascular interventions are performed by several specialties that may have opposing perspectives on these skills. A two round Delphi questionnaire approach was used. Experts from interventional cardiology, interventional radiology, and vascular surgery from the United States and Europe were invited to participate. An electronic questionnaire was generated by endovascular therapists with an appropriate educational background but who would not participate in subsequent rounds. The questionnaire consisted of 50 statements describing knowledge, technical, and behavioral skills during endovascular procedures. Experts received the questionnaires by email. They were asked to rate the importance of each skill on a Likert scale from 1 to 5. A statement was considered fundamental when more than 90% of the experts rated it 4 or 5 out of 5. Twenty-three of 53 experts invited agreed to participate: six interventional radiologists (2 USA, 4 Europe), 10 vascular surgeons (4 USA, 6 Europe), and seven interventional cardiologists (4 USA, 3 Europe). There was a 100% response rate in the first round and 87% in the second round. Results showed excellent consensus among responders (Cronbach's alpha = .95 first round; .93 second round). Ninety percent of all proposed skills were considered fundamental. The most critical skills were determined. A transatlantic multispecialty consensus was achieved about the content of "FES" among interventional radiologists, interventional cardiologists, and vascular surgeons from Europe and the United States. These results can serve as directive principles for developing endovascular training curricula

  5. Emergency Endovascular Treatment of Abdominal Aortic Aneurysms: Feasibility and Results

    International Nuclear Information System (INIS)

    Lagana, Domenico; Carrafiello, Gianpaolo; Mangini, Monica; Fontana, Federico; Caronno, Roberto; Castelli, Patrizio; Cuffari, Salvatore; Fugazzola, Carlo

    2006-01-01

    Purpose. To assess the feasibility and effectiveness of emergency endovascular treatment of abdominal aortic aneurysms (AAAs). Methods. During 36 months we treated, on an emergency basis, 30 AAAs with endovascular exclusion. In 21 hemodynamically stable patients preoperative CT angiography (CTA) was performed to confirm the diagnosis and to plan the treatment; 9 patients with hemorrhagic shock were evaluated with angiography performed in the operating room. Twenty-two Excluder (Gore) and 8 Zenith (Cook) stent-grafts (25 bifurcated and 5 aorto-uni-iliac) were used. The follow-up was performed by CTA at 1, 3, 6, and 12 months. Results. Technical success was achieved in 100% of cases with a 10% mortality rate. The total complication rate was 23% (5 increases in serum creatinine level and 2 wound infections). During the follow-up, performed in 27 patients (1-36 months, mean 15.2 months), 4 secondary endoleaks (15%) (3 type II, 2 spontaneously thrombosed and 1 under observation, and 1 type III treated by iliac extender insertion) and 1 iliac leg occlusion (treated with femoro-femoral bypass) occurred. We observed a shrinkage of the aneurysmal sac in 8 of 27 cases and stability in 19 of 27 cases; we did not observe any endotension. Conclusions. Endovascular repair is a good option for emergency treatment of AAAs. The team's experience allows correct planning of the procedure in emergency situations also, with technical results comparable with elective repair. In our experience the bifurcated stent-graft is the device of choice in patients with suitable anatomy because the procedure is less time-consuming than aorto-uni-iliac stent-grafting with surgical crossover, allowing faster aneurysm exclusion. However, further studies are required to demonstrate the long-term efficacy of endovascular repair compared with surgical treatment

  6. Dose rate determinations in the Portuguese Gamma Irradiation Facility: Monte Carlo simulations and measurements

    International Nuclear Information System (INIS)

    Oliveira, C.; Salgado, J.; Ferro de Carvalho, A.

    2000-01-01

    A simulation study of the Portuguese Gamma Irradiation Facility, UTR, has been carried out using the MCNP code. The work focused on the optimisation of the dose distribution inside the irradiation cell, dose calculations inside irradiated samples and dose calculations in critical points for protection purposes. Calculations were carried out at points inside and outside the irradiation cell, where different behaviour was expected (distance from the source, radiation absorption and scattering in irradiator structure and walls). The contributions from source, irradiator structure, sample material, carriers, walls, ceiling and floor to the photon spectra and air kerma at those points are reported and discussed. Air kerma measurements were also carried out using an ionisation chamber. Good agreement was found between experimental and calculated air kermas. (author)

  7. The effects of dose rate in total body irradiation of dogs

    International Nuclear Information System (INIS)

    Kolb, H.J.; Bodenberger, U.; Holler, E.; Thierfelder, S.; Eckstein, R.

    1986-01-01

    In summary the studies in dogs show that the dose rate or exposure time has a great impact on survival of acute radiation syndromes. In contrast the inactivation of colony forming hemopoietic precursors is less influenced by the dose rate. The potential of hemopoietic recovery is determined by the survival of hemopoietic precursor cells. Therefore in patients with a suspected whole body exposure of more than 1.50 Gy, bacterial and fungal decontamination and reverse isolation in a sterile environment has to be started immediately. Human patients treated with about 10 Gy of TBI frequently developed nausea, elevated temperatures and swelling of the parotic glands at the first and second day. The extent of these changes varies from patient to patient. The temperature is rarely elevated above 38.5 0 C. The swelling of parotics and the nausea subside within 48 hours. The presence of such systemic symptoms may suggest the exposure to a lethal dose of radiation. The disappearance of immature red cells, i.e. reticulocytes, and bandforms of granulocytes within the first 5 days supports this suggestion. HLA typing of the victim and his family should be performed as soon as possible after the accident. An HLA-identical sibling would be a suitable bone marrow donor. Unlike therapeutic TBI accidental exposures bring about uncertainties in the calculation of dose, dose distribution and dose rate. Early after irradiation biological changes are extremely variable. Both biological and physical data have to be considered, when microbiological decontamination, reverse isolation and transplantation of bone marrow are to be decided upon. Obviously these intensive therapeutic efforts are limited to a small number of victims. (orig.)

  8. Actual review of diagnostics and endovascular therapy of intracranial arterial stenoses

    International Nuclear Information System (INIS)

    Gizewski, E.R.; Weber, R.; Forsting, M.

    2011-01-01

    Approximately 6 - 50 % of all ischemic strokes are caused by intracranial arterial stenosis (IAS). Despite medical prevention, patients with symptomatic IAS have a high annual risk for recurrent ischemic stroke of about 12 %, and up to 19 % in the case of high-grade IAS (≥ 70 %). Digital subtraction angiography remains the gold standard for the diagnosis and grading of IAS. However, noninvasive imaging techniques including CT angiography, MR angiography, or transcranial Doppler and duplex ultrasound examinations are used in the clinical routine to provide additional information about the brain structure and hemodynamic. However, for technical reasons, the grading of stenoses is sometimes difficult and inaccurate. To date, aspirin is recommended as the treatment of choice in the prevention of recurrent ischemic stroke in patients with IAS. IAS patients who suffer a recurrent ischemic stroke or transient ischemic attack while taking aspirin can be treated with endovascular stenting or angioplasty in specialized centers. The periprocedural complication rate of these endovascular techniques is about 2 - 7 % at experienced neuro-interventional centers. The rate of re-stenosis is reported between 10 and 40 % depending on patient age and stenosis location. Further randomized studies comparing medical secondary prevention and endovascular therapy are currently being performed. With regard to the improvement of endovascular methods and lower complication rates, the indication for endovascular therapy in IAS could be broadened especially for stenosis in the posterior circulation. (orig.)

  9. [Actual review of diagnostics and endovascular therapy of intracranial arterial stenoses].

    Science.gov (United States)

    Gizewski, E R; Weber, R; Forsting, M

    2011-02-01

    Approximately 6 - 50% of all ischemic strokes are caused by intracranial arterial stenosis (IAS). Despite medical prevention, patients with symptomatic IAS have a high annual risk for recurrent ischemic stroke of about 12%, and up to 19% in the case of high-grade IAS (≥ 70%). Digital subtraction angiography remains the gold standard for the diagnosis and grading of IAS. However, noninvasive imaging techniques including CT angiography, MR angiography, or transcranial Doppler and duplex ultrasound examinations are used in the clinical routine to provide additional information about the brain structure and hemodynamic. However, for technical reasons, the grading of stenoses is sometimes difficult and inaccurate. To date, aspirin is recommended as the treatment of choice in the prevention of recurrent ischemic stroke in patients with IAS. IAS patients who suffer a recurrent ischemic stroke or transient ischemic attack while taking aspirin can be treated with endovascular stenting or angioplasty in specialized centers. The periprocedural complication rate of these endovascular techniques is about 2 - 7% at experienced neuro-interventional centers. The rate of re-stenosis is reported between 10 and 40% depending on patient age and stenosis location. Further randomized studies comparing medical secondary prevention and endovascular therapy are currently being performed. With regard to the improvement of endovascular methods and lower complication rates, the indication for endovascular therapy in IAS could be broadened especially for stenosis in the posterior circulation. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Effect of dose-rate of gamma irradiation (60Co) on the anti nutritional compounds phytic acid and antitrypsin on soybean (glycine max L.)

    International Nuclear Information System (INIS)

    Tanhindarto, R.P.; Hariyadi, P.; Purnomo, E.H.; Irawati, Z.

    2013-01-01

    An investigation on the effect of gamma irradiation at different dose-rate on the anti-nutritional compounds (phytic acid and antitrypsin) and the color of soybean has been conducted. The purpose of the study was to analyze the influence of the dose-rate on the rate of change of anti-nutritional compounds and color. Samples were irradiated with dose-rates of 1.30; 3.17; 5.71 and 8.82 kGy/hour with irradiation time varied from 0.5 to 55 hours. Phytic acid content and antitrypsin activity, as well as their L α b color values were analyzed. Results showed that a simple first order kinetics model can be used to describe changes in the concentration of the anti-nutritional compounds and color soybeans during the radiation processing. Data indicate that irradiation process at higher dose-rate (shorter time) is more effective in destroying anti-nutritional compounds as compared to that of irradiation process at lower dose-rate (longer time). Furthermore, irradiation process at higher dose-rate (shorter time) also have less detrimental effect on color of the soybean and the resulted soybean flour as compared to that of irradiation process at lower dose-rate (longer time). These findings suggest that irradiation process at a same dose may potentially be optimized by selecting the most appropriate combination of dose-rate and time of irradiation. (author)

  11. Effect of dose rate on inactivation of microorganisms in spices by electron-beams and gamma-rays irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Islam, Md.S.

    1994-01-01

    Total aerobic bacteria in spices used in this study were determined to be 1 x 10 6 to 6 x 10 7 per gram. A study on the inactivation of microorganisms in spices showed that doses of 6-9 kGy of EB (electron-beams) or γ-irradiation were required to reduce the total aerobic bacteria to below 10 3 per gram. However, a little increase of resistance was observed on the inactivation of total aerobic bacteria in many spices in case of EB irradiation. These differences of radiation sensitivities between EB and γ-rays was explained by dose rate effect on oxidation damage to microorganisms from the results of radiation sensitivities of Bacillus pumilus and B. megaterium spores at dry conditions. On the other hand, these high dose rate of EB irradiation suppressed the increase of peroxide values in spices at high dose irradiation up to 80 kGy. However, components of essential oils in spices were not changed even irradiated up to 50 kGy with EB and γ-rays. (author)

  12. Effect of dose rate, temperature and impurity content on the radiation damage in the electron irradiated NaCl crystals

    NARCIS (Netherlands)

    Dubinko, V.I.; Turkin, A.A.; Vainshtein, D.I.; Hartog, H.W. den

    The dependencies of void formation and radiolytic sodium accumulation on the irradiation dose, dose rate, temperature and impurity content are analyzed within a framework of a theoretical model, which is based on a new mechanism of dislocation climb. The mechanism involves the production of V-F

  13. Effects of ultraviolet irradiation on the rate and sequence of DNA replication in synchronized Chinese hamster cells

    International Nuclear Information System (INIS)

    Meyn, R.E.; Hewitt, R.R.; Thomson, L.F.; Humphrey, R.M.

    1976-01-01

    The effects of ultraviolet light (uv) irradiation on the rate of DNA replication in synchronized Chinese hamster ovary (CHO) cells were investigated. A technique for measuring semiconservative DNA replication was employed that involved growing the cells in medium containing 5-bromodeoxyuridine and subsequently determining the amount of DNA that acquired hybrid buoyant density in CsCl density gradients. One of the advantages of this technique was that it allowed a characterization of the extent of DNA replication as well as rate after irradiation. It was found that while there was a dose-dependent reduction in the rate of DNA replication following uv-irradiation, doses of up to 10 J/m 2 (which produce many dimers per replicon) did not prevent the ultimate replication of the entire genome. Hence, we conclude that dimers cannot be absolute blocks to DNA replication. In order to account for the total genome replication observed, a mechanism must exist that allows genome replication between dimers. The degree of reduction in the rate of replication by uv was the same whether the cells were irradiated at the Gl-S boundary or 1 h into S-phase. Previous work had shown that cells in early S-phase are considerably more sensitive to uv than cells at the G1-S boundary. Experiments specifically designed to test for reiterative replication showed that uv does not induce a second round of DNA replication within the same S-phase

  14. Determination of effective cross sections and production rates for tritium in the irradiation experiment TRIDEX

    International Nuclear Information System (INIS)

    Weise, L.

    1986-04-01

    In the framework of the development of a fusion reactor blanket the irradiation experiment TRIDEX (Tritium Recovery Irradiation DIDO Experiment) takes place at the Juelich Research Reactor FRJ-2 (DIDO). For this equipment the required neutronic calculations have been performed. The aim was the determination of the neutron spectrum and several therefrom derived integral parameters for the irradiation positions in interest. From the calculated effective cross sections for the formation of Tritium resulting from irradiated Lithium samples on one hand and from measured neutron flux densities on the other hand, all needed quantities of the Tritium production could be determined. The calculation of the neutron spectrum has been performed in a two-dimensional x-y-geometry. The neutron flux densities have been gained by gamma-spectrometric measurement of the activities in irradiated activation samples. (orig.) [de

  15. Assessment of axial gamma dose rate profile on irradiated fuel assembly using polycarbonate film and perspex dosimeters

    International Nuclear Information System (INIS)

    Joshi, V.B.; Janardhanan, S.; Pillai, P.R.; Somanathan, K.; Narayan, K.K.; John, J.; Kutty, K.N.; Deo, V.R.; Popli, O.L.

    1986-01-01

    The dose-rate profile of irradiated fuel rod is required for optimisation of radiation shielding from safety point of view during storage, handling and metallurgical examination. Since the dose-rates are in kilogray per hour, their determination requires special evaluation techniques. This paper illustrates the application of Makrofol-N and red perspex (AERE 4034B) for this purpose. They are compared with CaSO 4 :Dy thermoluminescence dosimeter. (author). 4 refs

  16. Postoperative vaginal cuff irradiation using high dose rate remote afterloading: a Phase II clinical protocol

    International Nuclear Information System (INIS)

    Noyes, William R.; Bastin, Kenneth; Edwards, Scott A.; Buchler, Dolores A.; Stitt, Judith A.; Thomadsen, Bruce R.; Fowler, Jack F.; Kinsella, Timothy J.

    1995-01-01

    Purpose: In September 1989, a postoperative Phase II high dose rate (HDR) brachytherapy protocol was started for International Federation of Gynecology and Obstetrics (FIGO) Stage I endometrial adenocarcinoma. This review reports the overall survival, local control, and complication rates for the initial 63 patients treated in this Phase II study. Methods and Materials: High dose rate brachytherapy was delivered using an Iridium-192 HDR remote afterloader. Sixty-three patients were entered into the Phase II protocol, each receiving two vaginal cuff treatments 1 week apart (range 4-12 days) with vaginal ovoids (diameter 2.0-3.0 cm). No patient received adjuvant external beam radiation. A dose of 32.4 Gy in two fractions was prescribed to the ovoid surface in 63 patients. The first three patients treated at our institution received 15, 16.2, and 29 Gy, respectively, to determine acute effects. Results: At a median follow-up of 1.6 years (range 0.75-4.3 years) no patient has developed a vaginal cuff recurrence. One regional recurrence (1.6%) occurred at 1.2 years at the pelvic side wall. This patient is alive and without evidence of disease 7 months after completion of salvage irradiation, which resulted in the only vaginal stenosis (1.6%). Fourteen patients (22%) experienced vaginal apex fibrosis by physical exam, which was clinically symptomatic in four patients. Two patients reported stress incontinence; however, these symptoms were noted prior to their HDR therapy. One patient died 2.4 years after HDR therapy due to cardiovascular disease without evidence of cancer at autopsy. Conclusion: Preliminary results of our phase II HDR vaginal cuff protocol for postoperative FIGO Stage IA, Grade 3 or Stage IB, Grade 1-2 patients demonstrate that 32.4 Gy in two fractions is well tolerated by the vaginal cuff mucosa. Local control appears comparable to our prior experience and others with low dose rate (LDR) brachytherapy. Additional patient accrual and further follow

  17. Radiological protection issues in endovascular use of radiation sources

    International Nuclear Information System (INIS)

    2006-02-01

    The use of radiation from radioactive materials for cancer treatment is well established. However, examples of uses of radiation therapy for benign conditions have been limited. Placing a radioactive source in the blood vessel so as to irradiate the surrounding inner periphery of the vessel has been attempted in recent years to prevent restenosis after percutaneous coronary and peripheral interventions. This kind of endovascular application provides treatment options that are less invasive for various vascular conditions compared with open surgery. As a part of the International Atomic Energy Agency's (IAEA) function for providing for application of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) that were jointly sponsored by the IAEA, FAO, ILO, OECD/NEA, PAHO and WHO, the IAEA planned a coordinated research project (CRP) that was to start in 2002 on radiological protection problems in endovascular use of radiation sources. However, as experts soon realized that the interest in this modality was waning, the CRP was not initiated. Nevertheless, it was felt that it would be appropriate to compile the information available on radiological protection problems observed so far and their possible solutions. This work was seen as part of a broader IAEA programme that covered accident prevention in radiotherapy. Publications on this topic have included, inter alia, Lessons Learned from Accidental Exposures in Radiotherapy (Safety Reports Series No. 17); Accidental Overexposure of Radiotherapy Patients in Bialystok; Investigation of an Accidental Exposure of Radiotherapy Patients in Panama; Accidental Overexposure of Radiotherapy Patients in San Jose, Costa Rica; and Investigation of an Accidental Exposure of Radiotherapy Patients in Poland. Keeping in mind that endovascular applications involve specialists such as cardiologists, angiologists and surgeons, all of whom might not have a

  18. Visuospatial and psychomotor aptitude predicts endovascular performance of inexperienced individuals on a virtual reality simulator.

    Science.gov (United States)

    Van Herzeele, Isabelle; O'Donoghue, Kevin G L; Aggarwal, Rajesh; Vermassen, Frank; Darzi, Ara; Cheshire, Nicholas J W

    2010-04-01

    This study evaluated virtual reality (VR) simulation for endovascular training of medical students to determine whether innate perceptual, visuospatial, and psychomotor aptitude (VSA) can predict initial and plateau phase of technical endovascular skills acquisition. Twenty medical students received didactic and endovascular training on a commercially available VR simulator. Each student treated a series of 10 identical noncomplex renal artery stenoses endovascularly. The simulator recorded performance data instantly and objectively. An experienced interventionalist rated the performance at the initial and final sessions using generic (out of 40) and procedure-specific (out of 30) rating scales. VSA were tested with fine motor dexterity (FMD, Perdue Pegboard), psychomotor ability (minimally invasive virtual reality surgical trainer [MIST-VR]), image recall (Rey-Osterrieth), and organizational aptitude (map-planning). VSA performance scores were correlated with the assessment parameters of endovascular skills at commencement and completion of training. Medical students exhibited statistically significant learning curves from the initial to the plateau performance for contrast usage (medians, 28 vs 17 mL, P dexterity as well as with image recall at end of the training period. In addition to current recruitment strategies, VSA may be a useful tool for predictive validity studies.

  19. Antioxidative system in the liver of rates subjected to combined irradiation injury

    International Nuclear Information System (INIS)

    Simovic, M.; Stanimirovic, D.; Ivanovic, L.; Markovic, M.; Letic-Gavrilovic, A.; Jovic, P.; Savic, J.; Spasic, M.; Saicic, Z.S.

    1991-01-01

    Until the Chernobyl nuclear plant catastrophe, exposure to radiation combined with other forms of injuries was usually considered as a hazard of nuclear war. The effect of combined irradiation injuries are often defined as the simultaneous effect of irradiation and another noxious stimulus. In the authors' opinion (1) one may talk about combined irradiation injuries (CII) only in the case when the general response of an organism to traumatization is the combination of biological reactions to at least two different etiologic noxious stimuli of which one is irradiation. One of the basic problems of combined injuries in general and CII in particular, is the syndrome of mutual aggravation (SMA) expressed through a very high (potentiated) lethality. The real mechanism(s) of this syndrome is still unknown. In our model of combined irradiation injury, potentiation of irradiation effect was smaller if animals were irradiated in the hypometabolic (open-quotes ebbclose quotes) compared to the hypermetabolic (open-quotes flowclose quotes) phase after thermal injury. Since the oxygen uptake is greater in the hypermetabolic phase the free radical production is also greater. On the other hand, the transition of hypometabolic to hypermetabolic phase could be analogous to a hypoxia/reoxygenation state. According to Granger et al. this state induces an increase in free radical production. When irradiation injury follows scalding it induces a new flux of free radicals. As a result the antioxidative defense of an organism could be overwhelmed and a disturbance of oxidative-antioxidative processes might occur. Thus, the authors suppose that overwhelmed antioxidative defense could be the reason for potentiated lethality in combined irradiation injury. 12 refs., 2 tabs

  20. Identifying patients with AAA with the highest risk following endovascular repair.

    Science.gov (United States)

    Cadili, Ali; Turnbull, Robert; Hervas-Malo, Marilou; Ghosh, Sunita; Chyczij, Harold

    2012-08-01

    It has been demonstrated that endovascular repair of arterial disease results in reduced perioperative morbidity and mortality compared to open surgical repair. The rates of complications and need for reinterventions, however, have been found to be higher than that in open repair. The purpose of this study was to identify the predictors of endograft complications and mortality in patients undergoing endovascular abdominal aortic aneurysm (AAA) repair; specifically, our aim was to identify a subset of patients with AAA whose risk of periprocedure mortality was so high that they should not be offered endovascular repair. We undertook a prospective review of patients with AAA receiving endovascular therapy at a single institution. Collected variables included age, gender, date of procedure, indication for procedure, size of aneurysm (where applicable), type of endograft used, presence of rupture, American Society of Anesthesiologists (ASA) class, major medical comorbidities, type of anesthesia (general, epidural, or local), length of intensive care unit (ICU) stay, and length of hospital stay. These factors were correlated with the study outcomes (overall mortality, graft complications, morbidity, and reintervention) using univariate and multivariate logistic regression. A total of 199 patients underwent endovascular AAA repair during the study period. The ICU stay, again, was significantly correlated with the primary outcomes (death and graft complications). In addition, length of hospital stay greater than 3 days, also emerged as a statistically significant predictor of graft complications in this subgroup (P = .024). Survival analysis for patients with AAA revealed that age over 85 years and ICU stay were predictive of decreased survival. Statistical analysis for other subgroups of patients (inflammatory AAA or dissection) was not performed due to the small numbers in these subgroups. Patients with AAA greater than 85 years of age are at a greater risk of mortality

  1. Preliminary studies on factors controlling the rate of regrowth of heavily x-irradiated rat rhabdomyosarcoma tumors

    International Nuclear Information System (INIS)

    Tenforde, T.S.; Curtis, S.B.; Woodruff, H.K.; Parks, D.L.; Daniels, S.J.; Crabtree, K.E.; Schilling, W.A.; DeGuzman, R.J.

    1977-12-01

    Following large single doses of x rays, rat rhabdomyosarcoma tumors exhibit a volume response which characteristically has a swelling phase, a regression phase, a rapid ''initial'' regrowth phase and a slow ''late'' regrowth phase. The preliminary experiments reported here were designed to examine three mechanisms that may underlie the reduction in growth rate occurring in the late regrowth phase; heritable non-lethal cellular damage, host immunity, delayed post-irradiation tissue and vascular damage. Based on retransplantation experiments and studies with immunosuppressed rats, neither heritable non-lethal damage nor host immune factors appear to influence the regrowth rate of tumors receiving radiation doses well below the cure level. After an x-ray dose approaching the cure level, regrowing tumors were observed to have a greatly reduced growth rate, possibly reflecting the presence of heritable non-lethal damage and/or an increased antigenicity of the heavily irradiated tumor cells. Morphometric analysis of histological sections did not reveal statistically significant abnormalities at the cellular level during the late regrowth phase, except for an increase in the percentage of necrotic tissue relative to non-irradiated tumors. The morphological resolution of small blood vessels was not adequate to evaluate delayed vascular damage in regrowing irradiated tumors

  2. MCNPX calculations of dose rate distribution inside samples treated in the research gamma irradiating facility at CTEx

    Energy Technology Data Exchange (ETDEWEB)

    Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G., E-mail: tiagorusin@ime.eb.b, E-mail: rebello@ime.eb.b, E-mail: vellozo@cbpf.b, E-mail: renatoguedes@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear; Vital, Helio C., E-mail: vital@ctex.eb.b [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (Brazil); Silva, Ademir X., E-mail: ademir@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear

    2011-07-01

    A cavity-type cesium-137 research irradiating facility at CTEx has been modeled by using the Monte Carlo code MCNPX. The irradiator has been daily used in experiments to optimize the use of ionizing radiation for conservation of many kinds of food and to improve materials properties. In order to correlate the effects of the treatment, average doses have been calculated for each irradiated sample, accounting for the measured dose rate distribution in the irradiating chambers. However that approach is only approximate, being subject to significant systematic errors due to the heterogeneous internal structure of most samples that can lead to large anisotropy in attenuation and Compton scattering properties across the media. Thus this work is aimed at further investigating such uncertainties by calculating the dose rate distribution inside the items treated such that a more accurate and representative estimate of the total absorbed dose can be determined for later use in the effects-versus-dose correlation curves. Samples of different simplified geometries and densities (spheres, cylinders, and parallelepipeds), have been modeled to evaluate internal dose rate distributions within the volume of the samples and the overall effect on the average dose. (author)

  3. MCNPX calculations of dose rate distribution inside samples treated in the research gamma irradiating facility at CTEx

    International Nuclear Information System (INIS)

    Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G.; Silva, Ademir X.

    2011-01-01

    A cavity-type cesium-137 research irradiating facility at CTEx has been modeled by using the Monte Carlo code MCNPX. The irradiator has been daily used in experiments to optimize the use of ionizing radiation for conservation of many kinds of food and to improve materials properties. In order to correlate the effects of the treatment, average doses have been calculated for each irradiated sample, accounting for the measured dose rate distribution in the irradiating chambers. However that approach is only approximate, being subject to significant systematic errors due to the heterogeneous internal structure of most samples that can lead to large anisotropy in attenuation and Compton scattering properties across the media. Thus this work is aimed at further investigating such uncertainties by calculating the dose rate distribution inside the items treated such that a more accurate and representative estimate of the total absorbed dose can be determined for later use in the effects-versus-dose correlation curves. Samples of different simplified geometries and densities (spheres, cylinders, and parallelepipeds), have been modeled to evaluate internal dose rate distributions within the volume of the samples and the overall effect on the average dose. (author)

  4. Effects of prolonged irradiation by low dose-rate ionizing radiation on the gene expression of hemopoietic factors of mice

    Energy Technology Data Exchange (ETDEWEB)

    Shirata, Katsutoshi; Saitou, Mikio; Yanai, Takanori; Sato, Fumiaki [Institute for Environmental Science, Rokkasho, Aomori (Japan)

    2000-07-01

    To evaluate the effect of prolonged low-dose irradiation on the gene expression of hemopoietic factors in tissues, gene expression was analyzed in the spleen as a hemopoietic tissue that is well known to be one of the most sensitive tissues to irradiation. SPF C3H/HeN female mice (Clea Japan Inc.) were irradiated under SPF conditions with {sup 137}Cs {gamma}-rays at doses of 2, 4, 6, and 8 Gy and a dose rate of 20 mGy/day. Non-irradiated mice of the same age were maintained as controls. At the end of the period of irradiation, both groups of mice were sacrificed and dissected to extract total RNA from their tissues. Reverse transcriptase-polymerase chain reaction (RT-PCR) and the Northern hybridization were employed to detect gene expression. RT-PCT showed no marked changes in the gene expression of GM-CSF. IL-6 gene expression was shown to tend to be enhanced by prolonged low-dose irradiation. The results of Northern hybridization showed that IL-6 mRNA was expressed slightly in both groups, and it was too weak to compare the difference in mRNA expression level between the irradiated group and the controls. No mRNA expression of GM-CSF was detected by Northern hybridization. Based on these results, it was concluded that the gene expression levels of IL-6 and GM-CSF were inadequate to detect the chemiluminescence signals without amplification. It was therefore concluded that improvement of detection sensitivity and larger RNA samples would be necessary for further analysis of the gene expression of hemopoietic factors. (K.H.)

  5. The radiation swelling effect on fracture properties and fracture mechanisms of irradiated austenitic steels. Part II. Fatigue crack growth rate

    Energy Technology Data Exchange (ETDEWEB)

    Margolin, B., E-mail: margolinbz@yandex.ru; Minkin, A.; Smirnov, V.; Sorokin, A.; Shvetsova, V.; Potapova, V.

    2016-11-15

    The experimental data on the fatigue crack growth rate (FCGR) have been obtained for austenitic steel of 18Cr-10Ni-Ti grade (Russian analog of AISI 321 steel) irradiated up to neutron dose of 150 dpa with various radiation swelling. The performed study of the fracture mechanisms for cracked specimens under cyclic loading has explained why radiation swelling affects weakly FCGR unlike its effect on fracture toughness. Mechanical modeling of fatigue crack growth has been carried out and the dependencies for prediction of FCGR in irradiated austenitic steel with and with no swelling are proposed and verified with the obtained experimental results. As input data for these dependencies, FCGR for unirradiated steel and the tensile mechanical properties for unirradiated and irradiated steels are used.

  6. Fenestrated endovascular aortic aneurysm repair using physician-modified endovascular grafts versus company-manufactured devices.

    Science.gov (United States)

    Dossabhoy, Shernaz S; Simons, Jessica P; Flahive, Julie M; Aiello, Francesco A; Sheth, Parth; Arous, Edward J; Messina, Louis M; Schanzer, Andres

    2017-12-07

    Fenestrated endografts are customized, patient-specific endovascular devices with potential to reduce morbidity and mortality of complex aortic aneurysm repair. With approval from the U.S. Food and Drug Administration, our center began performing fenestrated endovascular aneurysm repair through a physician-sponsored investigational device exemption (IDE #G130210), using both physician-modified endografts (PMEGs) and company-manufactured devices (CMDs). Because these techniques are associated with specific advantages and disadvantages, we sought to investigate differences in outcomes between PMEG and CMD cases. A single-institution retrospective review of all fenestrated endovascular aneurysm repairs was performed. The cohort was analyzed by device type (PMEG or CMD) after matching of cases on the basis of (1) number of target vessels intended for treatment, (2) extent of aneurysm, (3) aneurysm diameter, (4) device configuration, and (5) date of operation. Outcomes of ruptures, common iliac artery aneurysms, and aortic arch aneurysms were excluded. Demographics, operative details, perioperative complications, length of stay, and reinterventions were compared. For patients with >1 year of follow-up time, survival, type I or type III endoleak rate, target artery patency, and reintervention rate were estimated using the Kaplan-Meier method. Between November 30, 2010, and July 30, 2016, 82 patients were identified and matched. The cohort included 41 PMEG and 41 CMD patients who underwent repair of 38 juxtarenal (PMEG, 17; CMD, 21; P = .38), 14 pararenal (PMEG, 6; CMD, 8; P = .56), and 30 thoracoabdominal type I to type IV (PMEG, 18; CMD, 12; P = .17) aneurysms. There were significant differences in presentation requiring urgent aneurysm repair (PMEG, 9; CMD, 0; P = .002), total fluoroscopy time (PMEG, 76 minutes; CMD, 61 minutes; P = .02), volume of contrast material used (PMEG, 88 mL; CMD, 70 mL; P = .02), in-operating room to out-of-operating room time

  7. The influence of continuous γ-irradiation at decreasing dose-rate on the survival rote and induction of gene mutations in cultured Chinese hamster cells

    International Nuclear Information System (INIS)

    Feoktistova, T.P.; Elisova, E.V.; Stavrakova, N.M.

    1991-01-01

    Continuous γ-irradiation at decreasing dose-rate was shown to be less effective than acute exposure with regard to the lethal effect and frequency of mutations of resistance to 6-thioguanine in cultured Chinese hamster cells. The cell population subjected to continuons irradiation was d more radioresistant than the intact one. Lethal and genetic effects of continuous irradiation at decreasing dose-rate were mainly determined by the contribution of the radiation dose received during the first 24 h of exposure

  8. Laser-based irradiation apparatus and methods for monitoring the dose-rate response of semiconductor devices

    Science.gov (United States)

    Horn, Kevin M [Albuquerque, NM

    2006-03-28

    A scanned, pulsed, focused laser irradiation apparatus can measure and image the photocurrent collection resulting from a dose-rate equivalent exposure to infrared laser light across an entire silicon die. Comparisons of dose-rate response images or time-delay images from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems allows precise identification of those specific age-affected circuit structures within a device that merit further quantitative analysis with targeted materials or electrical testing techniques. Another embodiment of the invention comprises a broad-beam, dose rate-equivalent exposure apparatus. The broad-beam laser irradiation apparatus can determine if aging has affected the device's overall functionality. This embodiment can be combined with the synchronized introduction of external electrical transients into a device under test to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure.

  9. Inverse gamma ray dose rate effect in californium-252 RBE experiment with human T-1 cells irradiated in vitro

    International Nuclear Information System (INIS)

    Todd, P.; Feola, J.M.

    1986-01-01

    Metabolically deoxygenated suspensions of human T-1 cells were used to determine the RBE in hypoxia of low dose rate (LDR) Cf-252 radiation compared to LDR gamma radiation. Based upon the initial portion of the survival curves the RBE was 5.0 ± 1.0 for all components of the Cf-252 radiation and 7.1 ± 1.7 for the neutrons alone. An inverse dose rate effect was observed for LDR gamma radiation in which greater cell sensitivity was observed at lower dose rates and longer irradiation periods. It was demonstrated that there was little or no sublethal damage repair or cell progression during LDR at 21 deg C, and the observed decrease in cell survival probability with increasing irradiation time at a given dose was attributable to reoxygenation of the cell suspensions during the course of LDR exposures. (Auth.)

  10. Thoracic aortic aneurysms and dissections: endovascular treatment.

    Science.gov (United States)

    Baril, Donald T; Cho, Jae S; Chaer, Rabih A; Makaroun, Michel S

    2010-01-01

    The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine.

  11. The effect of low dose rate irradiation on the swelling of 12% cold-worked 316 stainless steel

    International Nuclear Information System (INIS)

    Allen, T. R.

    1999-01-01

    In pressurized water reactors (PWRs), stainless steel components are irradiated at temperatures that may reach 400 C due to gamma heating. If large amounts of swelling (>10%) occur in these reactor internals, significant swelling related embrittlement may occur. Although fast reactor studies indicate that swelling should be insignificant at PWR temperatures, the low dose rate conditions experienced by PWR components may possibly lead to significant swelling. To address these issues, JNC and ANL have collaborated to analyze swelling in 316 stainless steel, irradiated in the EBR-II reactor at temperatures from 376-444 C, at dose rates between 4.9 x 10 -8 and 5.8 x 10 -7 dpa/s, and to doses of 56 dpa. For these irradiation conditions, the swelling decreases markedly at temperatures less than approximately 386 C, with the extrapolated swelling at 100 dpa being around 3%. For temperatures greater than 386 C, the swelling extrapolated to 100 dpa is around 9%. For a factor of two difference in dose rate, no statistically significant effect of dose rate on swelling was seen. For the range of dose rates analyzed, the swelling measurements do not support significant (>10%) swelling of 316 stainless steel in PWRs

  12. Endovascular vein harvest: systemic carbon dioxide absorption.

    Science.gov (United States)

    Maslow, Andrew M; Schwartz, Carl S; Bert, Arthur; Hurlburt, Peter; Gough, Jeffrey; Stearns, Gary; Singh, Arun K

    2006-06-01

    Endovascular vein harvest (EDVH) requires CO(2) insufflation to expand the subcutaneous space, allowing visualization and dissection of the saphenous vein. The purpose of this study was to assess the extent of CO(2) absorption during EDVH. Prospective observational study. Single tertiary care hospital. Sixty patients (30 EDVH and 30 open-vein harvest) undergoing isolated coronary artery bypass graft surgery. Hemodynamic, procedural, and laboratory data were collected prior to (baseline), during, and at it the conclusion (final) of vein harvesting. Data were also collected during cardiopulmonary bypass (CPB). Data were compared by using t tests, analysis of variance, and correlation statistics when needed. There were significant increases in arterial CO(2) (PaCO(2), 35%) and decreases in pH (1.35%) during EDVH. These were associated with increases in heart rate, mean blood pressure, and cardiac output. Within the EDVH group, greater elevations (>10 mmHg) in PaCO2 were more likely during difficult harvest procedures, and these patients exhibited greater increase in heart rate. Elevated CO(2) persisted during CPB, requiring higher systemic gas flows and greater use of phenylephrine to maintain desired hemodynamics. EDVH was associated with systemic absorption of CO(2). Greater absorption was more likely in difficult procedures and was associated with greater hemodynamic changes requiring medical therapy.

  13. Macroarray analysis of gene expression in hematopoietic tissues from mice continuously irradiated by low dose-rate ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Saitou, Mikio; Nakamura, Shingo; Shirata, Katsutoshi; Yanai, Takanori; Izumi, Jun; Sugihara, Takashi; Tanaka, Satoshi; Tanaka, Kimio; Otsu, Hiroshi; Sato, Fumiaki [Inst. for Environmental Sciences, Rokkasho, Aomori (Japan)

    2002-07-01

    We found that the number of hematopoietic progenitor cells in bone marrow and spleen from 4 - 8 Gy-irradiated mice decreased about 50%, in spite of no change in the number of peripheral blood cells. To evaluate the effects of chronic irradiation by low dose-rate ionizing radiation on the gene expression in mice hematopoietic cells from bone marrow and spleen, the RNA expressions of more than 500 genes such as cytokine genes and oncogenes were measured on the membranes by the RNA macroarray analysis method at accumulated doses at 4.7 and 8 Gy in specific-pathogen-free (SPF) C3H/HeN female mice irradiated by {sup 137}Cs {gamma}-rays with the dose rate of 20 mGy/day. The RNA macroarray analysis in spleens from 8 Gy-irradiated mice showed that the expressions in 16 genes including noggin were more than 1.5 times larger than that of control, while those in 64 genes including shh (sonic hedgehog) and BMP-4 (bone morphogenesis protein 4) were more than 1.5 times smaller than that of control. (author)

  14. Effect of thermal treatment on the body temperature, respiration and pulse rate in dogs chronically irradiated with γ-rays

    International Nuclear Information System (INIS)

    Popova, N.A.; Petrovnin, M.G.

    1975-01-01

    Male dogs were chronically gamma-irradiated at different dose rates (0.06, 0.17, 0.34 rad/day) and subjected to heat treatment (raising of temperature from 22 0 C to 40 0 C) during winter and summer. Internal (rectal) temperature, respiration rate and heart rate were recorded. The respiration rate changed appreciably in all groups during all periods of temperature rise and fall in the chamber, but the variations were more pronounced in all groups during the winter experiment than during the summer experiment; no significant differences were found between the groups of animals while the respiration rate was changing, either in the winter or in the summer experiment. In both experiments, there were considerable heart rate variations only in the control group and in the group exposed to a dose rate of 0.06 rad/day. (V.A.P.)

  15. A Performance Evaluation of a Notebook PC under a High Dose-Rate Gamma Ray Irradiation Test

    Directory of Open Access Journals (Sweden)

    Jai Wan Cho

    2014-01-01

    Full Text Available We describe the performance of a notebook PC under a high dose-rate gamma ray irradiation test. A notebook PC, which is small and light weight, is generally used as the control unit of a robot system and loaded onto the robot body. Using TEPCO’s CAMS (containment atmospheric monitoring system data, the gamma ray dose rate before and after a hydrogen explosion in reactor units 1–3 of the Fukushima nuclear power plant was more than 150 Gy/h. To use a notebook PC as the control unit of a robot system entering a reactor building to mitigate the severe accident situation of a nuclear power plant, the performance of the notebook PC under such intense gamma-irradiation fields should be evaluated. Under a similar dose-rate (150 Gy/h gamma ray environment, the performances of different notebook PCs were evaluated. In addition, a simple method for a performance evaluation of a notebook PC under a high dose-rate gamma ray irradiation test is proposed. Three notebook PCs were tested to verify the method proposed in this paper.

  16. Dose and dose rate effects of whole-body gamma-irradiation: II. Hematological variables and cytokines

    Science.gov (United States)

    Gridley, D. S.; Pecaut, M. J.; Miller, G. M.; Moyers, M. F.; Nelson, G. A.

    2001-01-01

    The goal of part II of this study was to evaluate the effects of gamma-radiation on circulating blood cells, functional characteristics of splenocytes, and cytokine expression after whole-body irradiation at varying total doses and at low- and high-dose-rates (LDR, HDR). Young adult C57BL/6 mice (n = 75) were irradiated with either 1 cGy/min or 80 cGy/min photons from a 60Co source to cumulative doses of 0.5, 1.5, and 3.0 Gy. The animals were euthanized at 4 days post-exposure for in vitro assays. Significant dose- (but not dose-rate-) dependent decreases were observed in erythrocyte and blood leukocyte counts, hemoglobin, hematocrit, lipopolysaccharide (LPS)-induced 3H-thymidine incorporation, and interleukin-2 (IL-2) secretion by activated spleen cells when compared to sham-irradiated controls (p factor-beta 1 (TGF-beta 1) and splenocyte secretion of tumor necrosis factor-alpha (TNF-alpha) were not affected by either the dose or dose rate of radiation. The data demonstrate that the responses of blood and spleen were largely dependent upon the total dose of radiation employed and that an 80-fold difference in the dose rate was not a significant factor in the great majority of measurements.

  17. Changes of chromosome aberration rate and micronucleus frequency along with accumulated dose in continuously irradiated mice with a low dose rate of γ-rays

    International Nuclear Information System (INIS)

    Tanaka, Kimio; Izumi, Jun; Yanai, Takanori; Ichinohe, Kazuaki; Matsumoto, Tsuneya

    2003-01-01

    Chromosome aberrations in chronically exposed workers in nuclear facilities and medical radiologists have been reported. However chronological change of chromosome aberration rates along with accumulated dose has not been well studied. Chromosome aberrations and micronuclei in spleen lymphocytes were observed serially in mice continuously irradiated with a low dose rate of 20 mGy/day up to 400 days. Chromosome aberration rates were rapidly increased to 11.1% at 1 Gy, while micronucleus incidence increased at 5 Gy. After these doses their increase rates were saturated. Micronucleus incidence in bone marrow erythroblasts was higher than in spleen cells. These chronological changes of cytogenetic aberrations seem to be induced through a balance between developments of chromosome aberrations and micronuclei, and life span of spleen lymphocytes. These results will be helpful for risk assessment in low dose rate radiation exposure. (author)

  18. External beam radiotherapy alone or combined with high-dose-rate intracavitary irradiation in the treatment of cancer of the esophagus

    International Nuclear Information System (INIS)

    Hishikawa, Y.; Taniguchi, M.; Kamikonya, N.; Tanaka, S.; Miura, T.

    1988-01-01

    Autopsy findings of 35 patients, treated with radiotherapy for an esophageal carcinoma, were reviewed. A residual tumor was seen at autopsy in 7 of 16 patients treated with high-dose-rate intracavitary irradiation following external irradiation, in 13 of 14 patients treated with external irradiation of 50 Gy or more, and in all 5 patients treated with external irradiation of less than 50 Gy. Incidence on lymph node metastasis, at autopsy, did not diifer between the combined radiotherapy group and the external irradiation groups. However, it correlated with disease stage. It was observed in 11 of 17 patients with Stage 1 and Stage 2 disease, compared to 17 of 18 patients with Stage 3 and Stage 4 disease. Distant organ metastasis, at autopsy, also did not differ between the combined radiotherapy group and the external irradiation groups, and was also correlated with disease stage. It was found in 8 of 17 patients with Stage 1 and Stage 2 disease, compared to all 18 patients with Stage 3 and Stage 4 disease. Mean survival was different between the patients treated by high-dose-rate intracavitary irradiation following external irradiation and those treated by external irradiation alone; 11.3 months in the 16 patients treated with combined therapy, as compared to 6.9 months in the 14 patients who received external irradiation of 50 Gy or more, and 3.6 months in the 5 patients who received external irradiation of less than 50 Gy. 6 refs.; 5 tabs

  19. G2 arrest and apoptosis of cultured Raji cells by continuous low dose rate beta irradiation therapy with 188Re-perrhenate

    International Nuclear Information System (INIS)

    Yim, S. J.; Kim, E. H.; Lee, T. S.; Woo, K. S.; Jeong, W. S.; Choi, C. W.; Yim, S. M.

    2001-01-01

    Beta emitting radionuclide therapy gives exponentially decreasing radiation dose rate and results in cell death presumably by apoptosis. We observed changes in DNA content and apoptosis in relatively low dose rate beta irradiation. Raji cells were cultured and incubated with 188Re-perrhenate (3.7MBq, or 370MBq/ml) for 4 hours to give irradiation dose of 0.4, 4, or 40 Gy. After changing the culture media, cells were cultured for 2,4,8,16, and 24 hours. The cells were stained with Trypan blue, Annexin-V and Propidium Iodide (PI) to observe cell viability, cell membrane alternation by apoptosis and changes in DNA content respectively. Flowcytometry was done for Annexin-V and PI to quantitate apoptosis and necrosis in the irradiated cells. DAPI(4,6-diamidino-2-phenylindole) stain was also done to observe the damage in the nucleus. Cell viability decreased with an increasing radiation dose. Cells irradiated in 40 Gy showed early uptake of both Annexin-V and PI suggesting cell death by necrosis. Cells irradiated in 0.4 Gy showed delayed uptake of Annexin-V only, and later on PI uptake suggesting cell death mainly by apoptosis. The cells irradiated in 0.4 Gy showed G2 arrest in 16 hours after irradiation, but the cells irradiated in 40 Gy showed early DNA fragmentation within 2 hours after irradiation. In DAPI stain, early nucleus damage was observed in the cells irradiated in 40 Gy. On the other hand, slowly increasing apoptotic bodies were observed in the cells irradiated in 0.4 Gy. These results suggest that continuous low-dose irradiation induces G2 arrest and progressive apoptosis in cells while continuous high-dose irradiation induces rapid necrosis. Therefore, we expect therapeutic effect by continuous low-dose rate irradiation with beta emitting radiopharmaceuticals

  20. Radiobiological basis of total body irradiation with different dose rate and fractionation: repair capacity of hemopoietic cells

    International Nuclear Information System (INIS)

    Song, C.W.; Kim, T.H.; Khan, F.M.; Kersey, J.H.; Levitt, S.H.

    1981-01-01

    Total body irradiation (TBI) followed by bone marrow transplantation is being used in the treatment of malignant or non-malignant hemopoietic disorders. It has been believed that the ability of hemopoietic cells to repair sublethal radiation damage is negligible. Therefore, several schools of investigators suggested that TBI in a single exposure at extremely low dose rate (5 rad/min) over several hours, or in several fractions in 2-3 days, should yield a higher therapeutic gain, as compared with a single exposure at a high dose rate (26 rad/min). We reviewed the existing data in the literature, in particular, the response of hemopoietic cells to fractionated doses of irradiation and found that the repair capacity of both malignant and non-malignant hemopoietic cells might be greater than has been thought. It is concluded that we should not underestimate the ability of hemopoietic cells to repair sublethal radiation damage in using TBI

  1. Depression of DNA synthesis rate following hyperthermia, gamma irradiation, cyclotron neutrons and mixed modalities

    International Nuclear Information System (INIS)

    Weber, H.J.; Muehlensiepen, H.; Porschen, W.; Feinendegen, L.E.; Dietzel, F.

    1978-01-01

    The incorporation of the thymidine analogue I-UdR is proportional to the activity of DNA synthesis. The maximum depression of 125-I-UdR incorporation occurs approximately 4 hours after all kinds of treatment. The increase which follow reflects cell processes like reoxygeneration, recovery, recycling and recruitment (although a direct relation is not yet demonstrable). The degree of depression 4 hours after treatment and the time required needs to reach control level is dependent on dose and radiation quaility but no such dependence could be clearly seen for the times of hyperthermia treatment we used. Neutron irradiation and the combination gamma irradiation + hyperthermia show a higher depression and a slower return to normal than gamma irradiation at the same dose. (orig.) [de

  2. Cytogenetic determination of the effect of irradiation on in vitro lymphocyte transformation rates

    International Nuclear Information System (INIS)

    Lloyd, D.C.; Dolphin, G.W.; Purrott, R.J.

    1976-01-01

    The effect of x irradiation on the yield of transformed cells in 48-hr cultures has been studied in human peripheral-blood lymphocytes. Cytogenetic damage was used as a marker, aberration yields being obtained for mixed cultures prepared from equal numbers of normal and irradiated lymphocytes and from pure cultures of irradiated cells. Comparison of data from these two types of culture shows that the yield observed ranged from 90 percent of that expected at 50 rads to 11 percent at 700 rads. Poisson analysis demonstrated that for all doses, cells with high levels of structural damage were not selectively eliminated. The extent to which mitotic delay contributes to the reduction in numbers of transformed cells was examined by varying the time in cultures from 36 to 72 hr. The implication of this work in the field of radiation-dose estimation by chromosome-aberration analysis is discussed

  3. Prediction of response to continuous irradiation at low dose rate for repeated administrations in radiotherapy with beta emitters

    International Nuclear Information System (INIS)

    Calderon, Carlos; Gonzalez, Joaquin; Quesada, Waldo

    2009-01-01

    The absorbed dose to tumors after systemic administration of radiopharmaceuticals is not sufficient to achieve acceptable levels of probability of tumor control without compromising on critical tissue toxicity (kidney and / or bone marrow (BM)). There are reports of trials with multiple administrations, about tolerance level inter-administration intervals to allow recovery of the BM, with good results. The biokinetic behavior of some radiopharmaceuticals known makes possible the application of several administrations with short intervals of time.It is the present work combines two kinetic models of tumor growth and cell kinetics in the BM for predicting the response to continuous irradiation at low dose rate. The estimation of the effects of irradiation on tumor and kidneys was done using a formulation of the linear-quadratic model functions suitable for dose rate and multi-exponential repair. The estimation of the response in WB performed using a compartmental model previously reported. The absorbed dose to organs were calculated using the MIRD formulation taking into account the effect of irradiation cross. Biokinetic data were used for therapeutic radiopharmaceuticals 90Y, 131I and 177Lu, as well as radiobiological parameters reported for experimental animals. The effect on the response by the variation of inter-administration interval in slow-growing tumors and fast, so as the radiosensitive and radioresistant tumors. You can set conditions irradiation to an acceptable level of thrombocytopenia (onset and duration of the minimum in the curve) and renal irradiation below the limit of tolerance. It is possible to design experiments evaluation of therapeutic radiopharmaceuticals with a greater degree of refinement. (author)

  4. Gamma irradiator

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

    Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

  5. Determination of photoformation rates and scavenging rate constants of hydroxyl radicals in natural waters using an automatic light irradiation and injection system

    International Nuclear Information System (INIS)

    Nakatani, Nobutake; Hashimoto, Norichika; Shindo, Hirotaka; Yamamoto, Masatoshi; Kikkawa, Megumi; Sakugawa, Hiroshi

    2007-01-01

    Photoformation rates and scavenging rate constants of hydroxyl radicals (·OH) in natural water samples were determined by an automatic determination system. After addition of benzene as a chemical probe to a water sample in a reaction cell, light irradiation and injection of irradiated water samples into an HPLC as a function of time were performed automatically. Phenol produced by the reaction between ·OH and the benzene added to the water sample was determined to quantify the ·OH formation rate. The rate constants of ·OH formation from the photolysis of nitrate ions, nitrite ions and hydrogen peroxide were comparable with those obtained in previous studies. The percent of expected ·OH photoformation rate from added nitrate ion were high in drinking water (97.4%) and river water (99.3%). On the other hand, the low percent (65.0%) was observed in seawater due to the reaction of ·OH with the high concentrations of chloride and bromide ions. For the automatic system, the coefficient of variance for the determination of the ·OH formation rate was less than 5.0%, which is smaller than that in the previous report. When the complete time sequence of analytical cycle was 40 min for one sample, the detection limit of the photoformation rate and the sample throughput were 8 x 10 -13 M s -1 and 20 samples per day, respectively. The automatic system successfully determined the photoformation rates and scavenging rate constants of ·OH in commercial drinking water and the major source and sink of ·OH were identified as nitrate and bicarbonate ions, respectively

  6. Naphthalene degradation in seawater by UV irradiation: The effects of fluence rate, salinity, temperature and initial concentration

    International Nuclear Information System (INIS)

    Jing, Liang; Chen, Bing; Zhang, Baiyu; Zheng, Jisi; Liu, Bo

    2014-01-01

    Highlights: • The removal of naphthalene follows first order kinetics in seawater. • Irradiance and temperature are the most influential factors. • An increase in irradiance can linearly promote photodegradation. • High salinity suppresses the photodegradation of naphthalene. - Abstract: A large amount of oil pollution at sea is produced by the operational discharge of oily wastewater. The removal of polycyclic aromatic hydrocarbons (PAHs) from such sources using UV irradiation has become attractive, yet the photolysis mechanism in seawater has remained unclear. This study examines the photodegradation kinetics of naphthalene in natural seawater through a full factorial design of experiments (DOE). The effects of fluence rate, salinity, temperature and initial concentration are investigated. Results show that fluence rate, temperature and the interaction between temperature and initial concentration are the most influential factors. An increase in fluence rate can linearly promote the photodegradation process. Salinity increasingly impedes the removal of naphthalene because of the existence of free-radical scavengers and photon competitors. The results will help understand the photolysis mechanism of PAHs and develop more effective methods for treating oily seawater generated from offshore industries

  7. Measurements of the reverse current of highly irradiated silicon sensors to determine the effective energy and current related damage rate

    Science.gov (United States)

    Wiehe, Moritz; Wonsak, S.; Kuehn, S.; Parzefall, U.; Casse, G.

    2018-01-01

    The reverse current of irradiated silicon sensors leads to self heating of the sensor and degrades the signal to noise ratio of a detector. Precise knowledge of the expected reverse current during detector operation is crucial for planning and running experiments in High Energy Physics. The dependence of the reverse current on sensor temperature and irradiation fluence is parametrized by the effective energy and the current related damage rate, respectively. In this study 18 n-in-p mini silicon strip sensors from companies Hamamatsu Photonics and Micron Semiconductor Ltd. were deployed. Measurements of the reverse current for different bias voltages were performed at temperatures of -32 ° C, -27 ° C and -23 ° C. The sensors were irradiated with reactor neutrons in Ljubljana to fluences ranging from 2 × 1014neq /cm2 to 2 × 1016neq /cm2. The measurements were performed directly after irradiation and after 10 and 30 days of room temperature annealing. The aim of the study presented in this paper is to investigate the reverse current of silicon sensors for high fluences of up to 2 × 1016neq /cm2 and compare the measurements to the parametrization models.

  8. Long term low dose rate irradiation causes recovery from type II diabetes and suppression of aging in type II diabetes-prone mice

    International Nuclear Information System (INIS)

    Namura, T.; Oda, T.

    2003-01-01

    The effects of low dose rate gamma irradiation on model C57BL/KsJ-db/db mice with Type II diabetes mellitus was investigated. These mice develop Type II diabetes by 10 weeks of age, due to obesity, and are characterized by hyperinsulinemia. A group of 12 female 10-week old mice were irradiated at 0.65 mGy/hr in the low dose rate irradiation facility in the Low Dose Radiation Research Center. The urine glucose levels of all of the mice were strongly positive at the beginning of the irradiation. In the irradiated group, a decrease in the glucose level was observed in three mice, one in the 35th week, another in the 52nd week and the third in the 80th week. No recovery from the diabetes was observed in the 12 mice of non-irradiated control group. There was no systematic change of body weight or consumption of food and drinking water between the irradiated group and the non-irradiated group or between the recovered mice and the non-recovered mice. Survival was better in the irradiated group. The surviving fraction at the age of 90 weeks was 75 % in the irradiated group but only 40 % in the non-irradiated. A marked difference was also observed in the appearance of the coat hair, skin and tail. The irradiated group was in much better condition. Mortality was delayed and the healthy appearance was prolonged in the irradiated mice by about 20-30 weeks compared with the control mice. These results suggest that the low dose irradiation modified the condition of the diabetic mice, leading not only to recovery from diabetes, but also to suppression of the aging process

  9. PERFORMANCE EVALUATION OF ENDOVASCULAR MYOCARDIUM REVASCULARIZATION IN RENAL TRANSPLANT RECIPIENTS

    Directory of Open Access Journals (Sweden)

    I. G. Ryadovoy

    2012-01-01

    Full Text Available Coronary artery stenting was performed at 75 renal transplant recipients. Diffuse multiple and expressed calcified coronary artery disease took place that created many difficulties during the procedures. In result of endovascular treatments positive dynamics of clinical condition in the nearest postoperative period was marked, tolerance to physical exercise was increased and according to this the functional class of angina was reduced. Cardiac and general mortality after treatment in comparison to the data of foreign authors was lower and comparable with demographic death rate of the population for persons of the same sex and age. 

  10. Endovascular Sharp Recanalization for Calcified Femoropopliteal Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Hsuan-Li Huang

    2012-01-01

    Full Text Available Endovascular intervention of peripheral chronic total occlusion (CTO is technically challenging and time consuming. Various techniques and devices are used to facilitate lesion crossing and improve the success rate of the procedure. However, these new devices are quite expensive and not readily available. We report 2 cases of peripheral CTO wherein the occlusions were successfully crossed by using stiff end of Terumo glidewire. This sharp recanalization may be a useful technique for the recanalization of calcified peripheral CTOs when conventional techniques fail and new devices are not readily available, but it is accompanied by the risk of distal atheroembolism.

  11. Opinion rating of comparison photographs of television pictures from CCD cameras under irradiation

    International Nuclear Information System (INIS)

    Reading, V.M.; Dumbreck, A.A.

    1991-01-01

    As part of the development of a general method of testing the effects of gamma radiation on CCD television cameras, this is a report of an experimental study on the optimisation of still photographic representation of video pictures recorded before and during camera irradiation. (author)

  12. Types and rate of cataract development in mice irradiated at different ages

    International Nuclear Information System (INIS)

    Gajewski, A.K.; Majewska, K.; Slowikowska, M.G.; Chomiczewski, K.; Kulig, A.

    1977-01-01

    The effect of age on the development of radiation cataract has been investigated in an inbred A strain of mice and, as a result, the patterns of age dependence and senile mice cataract development were obtained. In general, the lenses of mice 1 to 3 days old were the most sensitive to radiation; the maximum resistance was noted in 5-day-old mice, and from this age up to 3 to 7 weeks of life there was a period of increasing sensitivity. In older animals the lens sensitivity tends to level off. The early stages of cataract occurred in all irradiated groups at a younger age than in the control group, but the late stages occurred in irradiated groups at the same age as the senile cataract occurred in the control group. Two types of cataract were observed. One was typical for young irradiated mice 1 to 5 days of age and the other was typical for all remaining irradiated groups and for a control group. Also, an attempt was made to correlate the obtained results with the cell kinetics in normal lens epithelium

  13. Endovascular Radiofrequency Ablation for Varicose Veins

    Science.gov (United States)

    2011-01-01

    Executive Summary Objective The objective of the MAS evidence review was to conduct a systematic review of the available evidence on the safety, effectiveness, durability and cost–effectiveness of endovascular radiofrequency ablation (RFA) for the treatment of primary symptomatic varicose veins. Background The Ontario Health Technology Advisory Committee (OHTAC) met on August 26th, 2010 to review the safety, effectiveness, durability, and cost-effectiveness of RFA for the treatment of primary symptomatic varicose veins based on an evidence-based review by the Medical Advisory Secretariat (MAS). Clinical Condition Varicose veins (VV) are tortuous, twisted, or elongated veins. This can be due to existing (inherited) valve dysfunction or decreased vein elasticity (primary venous reflux) or valve damage from prior thrombotic events (secondary venous reflux). The end result is pooling of blood in the veins, increased venous pressure and subsequent vein enlargement. As a result of high venous pressure, branch vessels balloon out leading to varicosities (varicose veins). Symptoms typically affect the lower extremities and include (but are not limited to): aching, swelling, throbbing, night cramps, restless legs, leg fatigue, itching and burning. Left untreated, venous reflux tends to be progressive, often leading to chronic venous insufficiency (CVI). A number of complications are associated with untreated venous reflux: including superficial thrombophlebitis as well as variceal rupture and haemorrhage. CVI often results in chronic skin changes referred to as stasis dermatitis. Stasis dermatitis is comprised of a spectrum of cutaneous abnormalities including edema, hyperpigmentation, eczema, lipodermatosclerosis and stasis ulceration. Ulceration represents the disease end point for severe CVI. CVI is associated with a reduced quality of life particularly in relation to pain, physical function and mobility. In severe cases, VV with ulcers, QOL has been rated to be as bad

  14. Effect of γ irradiation on rate of wound healing in a scored confluent monolayer of cells and the repair-promoting role of W11-a12

    International Nuclear Information System (INIS)

    Shu Chongxiang; Lou Shufen; Cheng Tianmin; Li Shunan; Ran Xinze

    2002-01-01

    Objective: To investigate the effects of ionizing radiation on healing rate of experimental wound in a scored confluent monolayer of fibroblasts and vascular endothelial cells and the repair-promoting effect of W 11 -a 12 . Methods: The healing rates of the experimental wound in a scored confluent monolayer of 3T3 cells or ECV304 cells irradiated with 6 Gy 60 Co gamma rays were assayed by measuring the width of the wound. Results: After irradiation, the closure of scored wounds both in a confluent monolayer of 3T3 cells and in that of ECV304 cells was significantly delayed. The scored wound in a confluent monolayer of 3T3 cells was completely closed in the sham irradiation group, but it was only 77% in the irradiation group at the tenth hour post wounding. The healing rate of the scored wound in a confluent monolayer of irradiated ECV304 cells was 83.6% of that in the sham irradiation group W 11 -a 12 had good promoting action on the closure of wounds in scored confluent monolayers of these two kinds of cells. Conclusion: The direct inhibitory effects of irradiation on the proliferating and migrating capacity of both fibroblasts and vascular endothelial cells might be one of the important reasons for the delay of healing in irradiation-impaired wounds and W 11 -a 12 could promote healing of irradiation-impaired wound by means of enhancing cell migration and proliferation directly

  15. Dose and dose rate effects of whole-body gamma-irradiation: II. Hematological variables and cytokines

    Science.gov (United States)

    Gridley, D. S.; Pecaut, M. J.; Miller, G. M.; Moyers, M. F.; Nelson, G. A.

    2001-01-01

    The goal of part II of this study was to evaluate the effects of gamma-radiation on circulating blood cells, functional characteristics of splenocytes, and cytokine expression after whole-body irradiation at varying total doses and at low- and high-dose-rates (LDR, HDR). Young adult C57BL/6 mice (n = 75) were irradiated with either 1 cGy/min or 80 cGy/min photons from a 60Co source to cumulative doses of 0.5, 1.5, and 3.0 Gy. The animals were euthanized at 4 days post-exposure for in vitro assays. Significant dose- (but not dose-rate-) dependent decreases were observed in erythrocyte and blood leukocyte counts, hemoglobin, hematocrit, lipopolysaccharide (LPS)-induced 3H-thymidine incorporation, and interleukin-2 (IL-2) secretion by activated spleen cells when compared to sham-irradiated controls (p < 0.05). Basal proliferation of leukocytes in the blood and spleen increased significantly with increasing dose (p < 0.05). Significant dose rate effects were observed only in thrombocyte counts. Plasma levels of transforming growth factor-beta 1 (TGF-beta 1) and splenocyte secretion of tumor necrosis factor-alpha (TNF-alpha) were not affected by either the dose or dose rate of radiation. The data demonstrate that the responses of blood and spleen were largely dependent upon the total dose of radiation employed and that an 80-fold difference in the dose rate was not a significant factor in the great majority of measurements.

  16. γ-ray induced chromosome aberration in rabbit peripheral blood lymphocytes irradiated in partial and whole body and decline of aberration rate with time post-exposure

    International Nuclear Information System (INIS)

    Zhang Lianzhen; Deng Zhicheng; Wang Haiyan

    1997-01-01

    Te author presents the results of study on 60 Co γ-ray induced chromosome aberration in rabbits peripheral blood lymphocytes irradiated in partial and whole body and the aberration rate decrease with the time of post-exposure. The experiments included 5 groups, it was whole-body exposure group, partial-body exposure (abdomen and pelvic cavity) group, blood irradiation group in vitro and control group respectively. Radiation dose was 3.0 Gy delivered at rate of 0.5 Gy/min. The results show that it was no significant differences between whole body and in blood irradiation group. The chromosome aberration yield in whole body exposure group was higher than that in partial-body group and in the abdomen exposure group was higher than in that in the pelvic cavity irradiation; The chromosome aberration rate decreased with the time of post-exposure in partial and whole body by γ-ray irradiation

  17. The effect of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue

    Science.gov (United States)

    Foster, B. R.

    1974-01-01

    Cellular response and cell population kinetics were studied during lymphopoiesis in the thymus of the mouse under continuous gamma irradiation using autoradiographic techniques and specific labeling with tritiated thymidine. On the basis of tissue weights, it is concluded that the response of both the thymus and spleen to continuous low dose-rate irradiation is multiphasic. That is, alternating periods of steady state growth, followed by collapse, which in turn is followed by another period of homeostasis. Since there are two populations of lymphocytes - short lived and long-lived, it may be that different phases of steady state growth are mediated by different lymphocytes. The spleen is affected to a greater extent with shorter periods of steady-state growth than exhibited by the thymus.

  18. R7T7-type HLW glass alteration under irradiation. Study of the residual alteration rate regime

    International Nuclear Information System (INIS)

    Rolland, Severine

    2012-01-01

    In France, fission products and minor actinides remaining after reprocessing of spent nuclear fuel are confined in a borosilicate glass matrix, named R7T7, for disposal in a geological repository. However, in these conditions, after several thousand years, water could arrive in contact with glass and be radio-lysed. In this work, we investigated the irradiation influence and especially the influence of the energy deposition on the residual glass alteration rate regime in pure water. Two types of leaching tests have been carried out. The first were performed on radioactive glass and the second on a SON68 glass (nonradioactive surrogate of R7T7 glass) under external irradiation γ. (author) [fr

  19. Effects of a prolonged irradiation with low dose-rate ionizing radiation on the hemopoiesis of mice

    Energy Technology Data Exchange (ETDEWEB)

    Yanai, Takanori; Shirata, Katsutoshi; Saitou, Mikio; Tanaka, Satoshi; Onodera, Jun' ichi; Izumi, Jun; Otsu, Hiroshi; Sato, Fumiaki [Inst. for Environmental Sciences, Rokkasho, Aomori (Japan); Kanaiwa-Kudo, Syouko

    2000-07-01

    SPF C3H/HeN female mice were irradiated with {sup 137}Cs {gamma}-rays at doses of 1-8 Gy at the dose rate of 20 mGy/22 h/day. After irradiation, the numbers of CFU-S and CFU-GM in the bone marrow were determined. Number of peripheral blood cells was also counted. The day 12-CFU-S, which is in the earliest stage of differentiation, decreased as the dose increased. Decreases in the numbers of day 7-CFU-S and CFU-GM were also observed. Regardless of the severe decrease in the number of hemopoietic stem cells, no remarkable changes were observed in the number of peripheral blood cells, indicating an enhanced differentiation of the precursor cells. (author)

  20. A comparison of anti-tumor effects of high dose rate fractionated and low dose rate continuous irradiation in multicellular spheroids

    International Nuclear Information System (INIS)

    Kubota, Nobuo; Omura, Motoko; Matsubara, Sho.

    1997-01-01

    In a clinical experience, high dose rate (HDR) fractionated interstitial radiotherapy can be an alternative to traditional low dose rate (LDR) continuous interstitial radiotherapy for head and neck cancers. To investigate biological effect of HDR, compared to LDR, comparisons have been made using spheroids of human squamous carcinoma cells. Both LDR and HDR were delivered by 137 Cs at 37degC. Dose rate of LDR was 8 Gy/day and HDR irradiations of fraction size of 4, 5 or 6 Gy were applied twice a day with an interval time of more than 6 hr. We estimated HDR fractionated dose of 31 Gy with 4 Gy/fr to give the same biological effects of 38 Gy by continuous LDR for spheroids. The ratio of HDR/LDR doses to control 50% spheroids was 0.82. (author)

  1. Perioperative complications in endovascular neurosurgery: Anesthesiologist's perspective

    Science.gov (United States)

    Sharma, Megha U.; Ganjoo, Pragati; Singh, Daljit; Tandon, Monica S.; Agarwal, Jyotsna; Sharma, Durga P.; Jagetia, Anita

    2017-01-01

    Background: Endovascular neurosurgery is known to be associated with potentially serious perioperative complications that can impact the course and outcome of anesthesia. We present here our institutional experience in the anesthetic management of various endovascular neurosurgical procedures and their related complications over a 10-year period. Methods: Data was obtained in 240 patients pertaining to their preoperative status, details of anesthesia and surgery, perioperative course and surgery-related complications. Information regarding hemodynamic alterations, temperature variability, fluid-electrolyte imbalance, coagulation abnormalities and alterations in the anesthesia course was specifically noted. Results: Among the important complications observed were aneurysm rupture (2.5%), vasospasm (6.67%), thromboembolism (4.16%), contrast reactions, hemodynamic alterations, electrolyte abnormalities, hypothermia, delayed emergence from anesthesia, groin hematomas and early postoperative mortality (5.14%). Conclusion: Awareness of the unique challenges of endovascular neurosurgery and prompt and appropriate management of the associated complications by an experienced neuroanesthesiologist is vital to the outcome of these procedures. PMID:28413524

  2. Low-dose-rate intraoperative brachytherapy combined with external beam irradiation in the conservative treatment of soft tissue sarcoma

    International Nuclear Information System (INIS)

    Delannes, M.; Thomas, L.; Martel, P.; Bonnevialle, P.; Stoeckle, E.; Chevreau, Ch.; Bui, B.N.; Daly-Schveitzer, N.; Pigneux, J.; Kantor, G.

    2000-01-01

    Purpose: Conservative treatment of soft tissue sarcomas most often implies combination of surgical resection and irradiation. The aim of this study was to evaluate low-dose-rate intraoperative brachytherapy, delivered as a boost, in the local control of primary tumors, with special concern about treatment complications. Methods and Materials: Between 1986 and 1995, 112 patients underwent intraoperative implant. This report focuses on the group of 58 patients with primary sarcomas treated by combination of conservative surgery, intraoperative brachytherapy, and external irradiation. Most of the tumors were located in the lower limbs (46/58--79%). Median size of the tumor was 10 cm, most of the lesions being T2-T3 (51/58--88%), Grade 2 or 3 (48/58--83%). The mean brachytherapy dose was 20 Gy and external beam irradiation dose 45 Gy. In 36/58 cases, iridium wires had to be placed on contact with neurovascular structures. Results: With a median follow-up of 54 months, the 5-year actuarial survival was 64.9%, with a 5-year actuarial local control of 89%. Of the 6 patients with local relapse, 3 were salvaged. Acute side effects, essentially wound healing problems, occurred in 20/58 patients, late side effects in 16/58 patients (7 neuropathies G2 to G4). No amputation was required. The only significant factor correlated with early side effects was the location of the tumor in the lower limb (p = 0.003), and with late side effects the vicinity of the tumor with neurovascular structures (p = 0.009). Conclusion: Brachytherapy allows early delivery of a boost dose in a reduced volume of tissue, precisely mapped by the intraoperative procedure. Combined with external beam irradiation, it is a safe and efficient treatment technique leading to high local control rates and limited functional impairment

  3. Laser-based irradiation apparatus and method to measure the functional dose-rate response of semiconductor devices

    Science.gov (United States)

    Horn, Kevin M [Albuquerque, NM

    2008-05-20

    A broad-beam laser irradiation apparatus can measure the parametric or functional response of a semiconductor device to exposure to dose-rate equivalent infrared laser light. Comparisons of dose-rate response from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems can determine if aging has affected the device's overall functionality. The dependence of these changes on equivalent dose-rate pulse intensity and/or duration can be measured with the apparatus. The synchronized introduction of external electrical transients into the device under test can be used to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure while exposing the device to dose-rate equivalent infrared laser light.

  4. The effect of continuous gamma-irradiation at exponentially decreased dose rates on the nucleic acid content of haemopoietic organs and blood of rats

    International Nuclear Information System (INIS)

    Mishurova, E.; Kropachova, K.; Reksa, R.

    1992-01-01

    The effect of continuous gamma-irradiation at exponentially decreased dose rates on the nucleic acid content of rat hemopoietic tissues and blood was followed up. We have found that the dynamics of the changes seems to be similar to that observed after acute exposure, and the hemopoiesis recovery starts just at the time of irradiation. In evaluating the damage and recovery extent after accidental irradiation, we consider it expedient to complement the biological dosimetry with the indices studied work including the determination of DNA and RNA concentrations in blood of irradiated human beings

  5. Endovascular interventions for TASC II D femoropopliteal lesions.

    Science.gov (United States)

    Baril, Donald T; Chaer, Rabih A; Rhee, Robert Y; Makaroun, Michel S; Marone, Luke K

    2010-06-01

    Advances in endovascular techniques have provided new options in the treatment of complex infrainguinal occlusive lesions. The purpose of this study was to evaluate outcomes of endovascular interventions on TransAtlantic InterSociety (TASC) II D femoropopliteal occlusive disease. All patients undergoing endovascular interventions for femoropopliteal occlusive disease between July 2004 and July 2009 were reviewed. Patient demographics, pre- and postprocedure ankle-brachial indices (ABI) and anatomic factors were analyzed. Outcomes evaluated included primary patency, assisted-patency, secondary patency, predictors of restenosis, and wound healing. Five hundred eighty-five limbs were treated during the period reviewed. The study group included 79 TASC D limbs in 74 patients (mean age 76.5 +/- 11.9 years, male sex: 53%). Fifty-six limbs (71%) underwent treatment for critical limb ischemia, including 42 (53%) with tissue loss. Eleven patients (15%) had previous failed bypasses. Preoperative ABIs were unobtainable for 23 patients, while the remaining 56 had a mean baseline ABI of 0.54 +/- 0.28. There was one periprocedural mortality. Five patients (6.3%) had periprocedural complications. Mean increase in ABI postprocedure was 0.49 +/- 0.35. Follow-up was available for 74 limbs at a mean of 10.7 months (range, 1-35). There were 18 mortalities (24.3%) during the follow-up period. No patient required a major amputation during this follow-up period. Twenty-one limbs (26.6%) experienced restenosis and nine limbs (11.4%) experienced occlusion. Twenty-nine limbs underwent reintervention during the follow-up time, including nine which underwent multiple reinterventions. Primary, assisted-primary, and secondary patency rates at 12 and 24 months were 52.2%, 88.4%, 92.6% and 27.5%, 74.2%, and 88.9%, respectively. Predictors of restenosis/occlusion included hypercholesterolemia, the presence of a popliteal artery stent, and patients who were current or former smokers. Endovascular

  6. Endovascular Neurosurgery: Personal Experience and Future Perspectives.

    Science.gov (United States)

    Raymond, Jean

    2016-09-01

    From Luessenhop's early clinical experience until the present day, experimental methods have been introduced to make progress in endovascular neurosurgery. A personal historical narrative, spanning the 1980s to 2010s, with a review of past opportunities, current problems, and future perspectives. Although the technology has significantly improved, our clinical culture remains a barrier to methodologically sound and safe innovative care and progress. We must learn how to safely practice endovascular neurosurgery in the presence of uncertainty and verify patient outcomes in real time. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Effects of non-implantation factors on survival rate of microbe irradiated by low-energy N+

    International Nuclear Information System (INIS)

    Yang Tianyou; Chen Linhai; Qin Guangyong; Li Zongwei; Su Mingjie; Wang Yanping; Chang Shenghe; Huo Yuping; Li Zongyi

    2006-01-01

    The effects of non-implantation factors, such as drying, vacuum and the staying time of the E.coli LE392 culture, on survival rate of E.coli LE392 were studied when E.coli LE392 was irradiated by the low-energy N + . The results show that the survival rate of E.coli LE392 does not reduce steadily all the time but rapidly drops sometime during drying. The survival rate of E.coli LE392 declines sharply as the samples are placed in vacuum, then falls in distinctively with increasing of time. the tolerance of E.coli LE392 towards vacuum increasingly strengthens when the E.coli LE392 culture is placed at room temperature. Preparing the culture in batchs can ensure the consistency of the irradiated samples and avoid errors caused by the inconsistent samples. When the non-implantation factors are controlled, E.coli is implanted by 30 kev N + of 1 x 10 14 cm -2 and 3 x 10 15 cm -2 , respectively. And the results show no difference in the E.coli's survival rates between batchs at the same dose. (authors)

  8. Inhibition and recovery of the rate of DNA synthesis in V79 Chinese hamster cells following ultraviolet light irradiation

    International Nuclear Information System (INIS)

    Ventura, A.M.; Meneghini, R.

    1984-01-01

    Chinese hamster fibroblasts (V79 cell line) exhibit the phenomenon of recovery of DNA synthesis from the initial inhibition observed after ultraviolet light irradiation, in the absence of significant excision of pyrimidine dimers. In an attempt to determine whether the initial inhibition and subsequent recovery can be accounted for by parallel variations in the rate of movement of the replication fork, the cells were pulse-labeled with radioactive bromodeoxyuridine at different times following irradiation and their DNA centrifuged in neutral CsCl density gradients. When DNA synthesis inhibition was at a maximum, an accumulation of DNA, of density intermediate between hybrid and nonsubstituted DNA, was noticed in the density-distribution profiles. The density distribution of DNA along the gradient can provide an estimate of the rate of movement of the replication fork, and the results indicate that most of the variation in the overall rate of DNA synthesis can be accounted for by a parallel variation in the rate of fork movement. (Auth.)

  9. Modulation of toxicity following external beam irradiation preceded by high-dose rate brachytherapy in inoperable oesophageal cancer

    International Nuclear Information System (INIS)

    Taal, B.G.; Aleman, B.M.P.; Koning, C.C.E.; Boot, H.

    1996-01-01

    To induce fast relief of dysphagia in inoperable oesephageal cancer, we applied high-dose rate (HDR) intraluminal irradiation followed by external irradiation (EBRT) in a phase II study. 15 patients (group A: n = 15; 10 men, 5 women; median age 66 years) were treated with 10 Gy HDR brachytherapy plus 40 Gy EBRT (15 fractions of 2.67 Gy). Severe side-effects were encountered in 60% of patients: 3 late ulceration, 2 pending fistula and 2 patients with fatal haemorrhage after an interval of 6 months. Overall response was excellent: 9 complete remissions (60%) and 6 partial responses (40%). Because of the high toxicity rate, in a subsequent study (group B: n = 30; 23 mean, 7 women; median age 66 years) the EBRT scheme was changed using smaller fractions (2.0 Gy) to reach the same total dose of 40 Gy. The complication rate (17%) was significantly reduced, while the overall response remained excellent (83%): 17 complete and 8 partial responses. The impressive change in complication rate of HDR brachytherapy and EBRT stresses the impact of the fraction per dose and illustrates the small therapeutic margins. (author)

  10. Modulation of toxicity following external beam irradiation preceded by high-dose rate brachytherapy in inoperable oesophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Taal, B.G.; Aleman, B.M.P.; Koning, C.C.E.; Boot, H. [Nederlands Kanker Inst. `Antoni van Leeuwenhoekhuis`, Amsterdam (Netherlands)

    1996-09-01

    To induce fast relief of dysphagia in inoperable oesephageal cancer, we applied high-dose rate (HDR) intraluminal irradiation followed by external irradiation (EBRT) in a phase II study. 15 patients (group A: n = 15; 10 men, 5 women; median age 66 years) were treated with 10 Gy HDR brachytherapy plus 40 Gy EBRT (15 fractions of 2.67 Gy). Severe side-effects were encountered in 60% of patients: 3 late ulceration, 2 pending fistula and 2 patients with fatal haemorrhage after an interval of 6 months. Overall response was excellent: 9 complete remissions (60%) and 6 partial responses (40%). Because of the high toxicity rate, in a subsequent study (group B: n = 30; 23 mean, 7 women; median age 66 years) the EBRT scheme was changed using smaller fractions (2.0 Gy) to reach the same total dose of 40 Gy. The complication rate (17%) was significantly reduced, while the overall response remained excellent (83%): 17 complete and 8 partial responses. The impressive change in complication rate of HDR brachytherapy and EBRT stresses the impact of the fraction per dose and illustrates the small therapeutic margins. (author).

  11. Critical current densities and flux creep rate in Co-doped BaFe2As2 with columnar defects introduced by heavy-Ion irradiation

    International Nuclear Information System (INIS)

    Nakajima, Y.; Tsuchiya, Y.; Taen, T.; Yagyuda, H.; Tamegai, T.; Okayasu, S.; Sasase, M.; Kitamura, H.; Murakami, T.

    2010-01-01

    We report the formation of columnar defects in Co-doped BaFe 2 As 2 single crystals with different heavy-ion irradiations. The formation of columnar defects by 200 MeV Au ion irradiation is confirmed by transmission electron microscopy and their density is about 40% of the irradiation dose. Magneto-optical imaging and bulk magnetization measurements reveal that the critical current density J c is enhanced in the 200 MeV Au and 800 MeV Xe ion irradiated samples while J c is unchanged in the 200 MeV Ni ion irradiated sample. We also find that vortex creep rates are strongly suppressed by the columnar defects. We compare the effect of heavy-ion irradiation into Co-doped BaFe 2 As 2 and cuprate superconductors.

  12. Using the quantum yields of photosystem II and the rate of net photosynthesis to moniter high irradiance and temperature stress in chrysanthemum (Dendrantherma grandiflora)

    DEFF Research Database (Denmark)

    Janka, Eshetu; Körner, Oliver; Rosenqvist, Eva

    2015-01-01

    and quantum yield of PSII remaining low until the temperature reaches 28 °C and 2) the integration of online measurements to monitor photosynthesis and PSII operating efficiency may be used to optimise dynamic greenhouse control regimes by detecting plant stress caused by extreme microclimatic conditions.......Under a dynamic greenhouse climate control regime, temperature is adjusted to optimise plant physiological responses to prevailing irradiance levels; thus, both temperature and irradiance are used by the plant to maximise the rate of photosynthesis, assuming other factors are not limiting...... irradiance, the maximum Pn and ETR were reached at 24 °C. Increased irradiance decreased the PSII operating efficiency and increased NPQ, while both high irradiance and temperature had a significant effect on the PSII operating efficiency at temperatures >28 °C. Under high irradiance and temperature, changes...

  13. Endovascular Treatment of Epistaxis: Indications, Management, and Outcome

    International Nuclear Information System (INIS)

    Strach, Katharina; Schröck, Andreas; Wilhelm, Kai; Greschus, Susanne; Tschampa, Henriette; Möhlenbruch, Markus; Naehle, Claas P.; Jakob, Mark; Gerstner, Andreas O. H.; Bootz, Friedrich; Schild, Hans H.; Urbach, Horst

    2011-01-01

    Objective: Epistaxis is a common clinical problem, and the majority of bleedings can be managed conservatively. However, due to extensive and sometimes life-threatening bleeding, further treatment, such as superselective embolization, may be required. We report our experience with endovascular treatment of life-threatening epistaxis. Methods: All patients presenting with excessive epistaxis, which received endovascular treatment at a German tertiary care facility between January 2001 and December 2009, were retrospectively identified. Demographic data, etiology, origin and clinical relevance of bleeding, interventional approach, therapy-associated complications, and outcome were assessed. Results: A total of 48 patients required 53 embolizations. Depending on the etiology of bleeding, patients were assigned to three groups: 1) idiopathic epistaxis (31/48), 2) traumatic or iatrogenic epistaxis (12/48), and 3) hereditary hemorrhagic telangiectasia (HHT) (5/48). Eleven of 48 patients required blood transfusions, and 9 of these 11 patients (82%) were termed clinically unstable. The sphenopalatine artery was embolized unilaterally in 10 of 53 (18.9%) and bilaterally in 41 of 53 (77.4%) procedures. During the same procedure, additional vessels were embolized in three patients (3/53; 5.7%). In 2 of 53(3.8%) cases, the internal carotid artery (ICA) was occluded. Long-term success rates of embolization were 29 of 31 (93.5%) for group 1 and 11 of 12 (91.7%) for group 2 patients. Embolization of patients with HHT offered at least a temporary relief in three of five (60%) cases. Two major complications (necrosis of nasal tip and transient hemiparesis) occurred after embolization. Conclusions: Endovascular treatment proves to be effective for prolonged and life-threatening epistaxis. It is easily repeatable if the first procedure is not successful and offers a good risk–benefit profile.

  14. On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

  15. Preoperative Evaluation and Endovascular Procedure of Intraoperative Aneurysm Rupture During Thoracic Endovascular Aortic Repair

    Energy Technology Data Exchange (ETDEWEB)

    Zha, Bin-Shan, E-mail: binszha2013@163.com; Zhu, Hua-Gang, E-mail: huagzhu@yeah.net; Ye, Yu-Sheng, E-mail: yeyusheng@aliyun.com; Li, Yong-Sheng, E-mail: 872868848@qq.com; Zhang, Zhi-Gong, E-mail: zzgedward@sina.com; Xie, Wen-Tao, E-mail: 345344347@qq.com [The First Affiliated Hospital of Anhui Medical University, Department of Vascular Surgery (China)

    2017-03-15

    Thoracic aortic aneurysms are now routinely repaired with endovascular repair if anatomically feasible because of advantages in safety and recovery. However, intraoperative aneurysm rupture is a severe complication which may have an adverse effect on the outcome of treatment. Comprehensive preoperative assessment and considerate treatment are keys to success of endovascular aneurysm repair, especially during unexpected circumstances. Few cases have reported on intraoperative aortic rupture, which were successfully managed by endovascular treatment. Here, we present a rare case of an intraoperative aneurysm rupture during endovascular repair of thoracic aortic aneurysm with narrow neck and angulated aorta arch (coarctation-associated aneurysm), which was successfully treated using double access route approach and iliac limbs of infrarenal devices.Level of EvidenceLevel 5.

  16. Outcomes of fenestrated and branched endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms.

    Science.gov (United States)

    Schanzer, Andres; Simons, Jessica P; Flahive, Julie; Durgin, Jonathan; Aiello, Francesco A; Doucet, Danielle; Steppacher, Robert; Messina, Louis M

    2017-09-01

    More than 80% of infrarenal aortic aneurysms are treated by endovascular repair. However, adoption of fenestrated and branched endovascular repair for complex aortic aneurysms has been limited, despite high morbidity and mortality associated with open repair. There are few published reports of consecutive outcomes, inclusive of all fenestrated and branched endovascular repairs, starting from the inception of a complex aortic aneurysm program. Therefore, we examined a single center's consecutive experience of fenestrated and branched endovascular repair of complex aortic aneurysms. This is a single-center, prospective, observational cohort study evaluating 30-day and 1-year outcomes in all consecutive patients who underwent fenestrated and branched endovascular repair of complex aortic aneurysms (definition: requiring one or more fenestrations or branches). Data were collected prospectively through an Institutional Review Board-approved registry and a physician-sponsored investigational device exemption clinical trial (G130210). We performed 100 consecutive complex endovascular aortic aneurysm repairs (November 2010 to March 2016) using 58 (58%) commercially manufactured custom-made devices and 42 (42%) physician-modified devices to treat 4 (4%) common iliac, 42 (42%) juxtarenal, 18 (18%) pararenal, and 36 (36%) thoracoabdominal aneurysms (type I, n = 1; type II, n = 4; type III, n = 12; type IV, n = 18; arch, n = 1). The repairs included 309 fenestrations, branches, and scallops (average of 3.1 branch arteries/case). All patients had 30-day follow-up for 30-day event rates: three (3%) deaths; six (6%) target artery occlusions; five (5%) progressions to dialysis; eight (8%) access complications; one (1%) paraparesis; one (1%) bowel ischemia; and no instances of myocardial infarction, paralysis, or stroke. Of 10 type I or type III endoleaks, 8 resolved (7 with secondary intervention, 1 without intervention). Mean follow-up time was 563 days (interquartile range

  17. Endovascular treatment of renal aneurysms: A series of 18 cases

    International Nuclear Information System (INIS)

    Sédat, J.; Chau, Y.; Baque, J.

    2012-01-01

    Purpose: To retrospectively analyze the results and complications of the endovascular treatment of 18 renal aneurysms. Methods: From 2002 to 2011, 15 patients (aged 31–76), with 18 renal aneurysms, were admitted in our institution for treatment by embolization. Except one, all were wide-necked aneurysms. One aneurysm was treated by occluding the parent artery considering its distal location; a small-necked aneurysm was treated by simple coiling, and the remaining 16 were embolized utilizing adjunctive techniques to protect the parent artery. We analyzed the rates of technical success, complication and clinical consequence, post-operative occlusion and recurrence. Results: There was a 100% technical success rate. 15 aneurysms showed a total occlusion on the post-treatment angiogram. 2 aneurysms demonstrated neck remnants, and one had an intrasaccular residual in-flow. Two minor post-operative complications were encountered but resolved over time. No delayed clinical complications were observed and the long-term angiographic follow-up demonstrated stability of the occlusion of the target renal aneurysm with no major recurrence. Conclusion: Complications of the embolization of renal aneurysms are rare. Endovascular treatment should therefore be considered at first for the treatment of renal aneurysms.

  18. Accelerated partial breast irradiation in the elderly: 5-year results of high-dose rate multi-catheter brachytherapy

    International Nuclear Information System (INIS)

    Genebes, Caroline; Hannoun-Levi, Jean-Michel; Chand, Marie-Eve; Gal, Jocelyn; Gautier, Mathieu; Raoust, Ines; Ihrai, Tarik; Courdi, Adel; Ferrero, Jean-Marc; Peyrottes, Isabelle

    2014-01-01

    To evaluate clinical outcome after accelerated partial breast irradiation (APBI) in the elderly after high-dose-rate interstitial multi-catheter brachytherapy (HIBT). Between 2005 and 2013, 70 patients underwent APBI using HIBT. Catheter implant was performed intra or post-operatively (referred patients) after lumpectomy and axillary sentinel lymph node dissection. Once the pathological results confirmed the indication of APBI, planification CT-scan was performed to deliver 34 Gy/10f/5d or 32 Gy/8f/4d. Dose-volume adaptation was manually achieved (graphical optimization). Dosimetric results and clinical outcome were retrospectively analyzed. Physician cosmetic evaluation was reported. With a median follow-up of 60.9 months [4.6 – 90.1], median age was 80.7 years [62 – 93.1]. Regarding APBI ASTRO criteria, 61.4%, 18.6% and 20% were classified as suitable, cautionary and non-suitable respectively. Axillary sentinel lymph node dissection was performed in 94.3%; 8 pts (11.5%) presented an axillary involvement. A median dose of 34 Gy [32 – 35] in 8 to 10 fractions was delivered. Median CTV was 75.2 cc [16.9 – 210], median D90 EQD2 was 43.3 Gy [35 – 72.6] and median DHI was 0.54 [0.19 – 0.74]. One patient experienced ipsilateral recurrence (5-year local free recurrence rate: 97.6%. Five-year specific and overall survival rates were 97.9% and 93.2% respectively. Thirty-four patients (48%) presented 47 late complications classified grade 1 (80.8%) and grade 2 (19.2%) with no grade ≥ 3. Cosmetic results were considered excellent/good for 67 pts (95.7%). APBI using HIBT and respecting strict rules of implantation and planification, represents a smart alternative between no post-operative irradiation and whole breast irradiation delivered over 6 consecutive weeks

  19. Fluence-rate effects on irradiation embrittlement and composition and temperature effects on annealing/reirradiation sensitivity

    International Nuclear Information System (INIS)

    Hawthorne, J.R.; Hiser, A.L.

    1988-01-01

    Recent MEA investigation on the effect of neutron fluence rate on radiation-induced embrittlement accrual and the contributions of metallurgical variables to postirradiation annealing and re-irradiation behavior are reviewed. Studies of fluence-rate effects involved experiments in the UBR test reactor and separately, radiation sensitivity determinations for the decommissioned Gundremmingen (KRB-A) vessel material. Annealing-reirradiation studies employed 399 0 C and 454 0 C heat treatments. Material composition is shown to play a major role in postirradiation annealing recovery. Results illustrate effects of variable copper and variable nickel contents on recoveray of steel plate having low phosphorus levels. Composition effects on recovery were also observed for prototypic welds depicting high/low copper and high/low nickel contents and three flux types. The welds, in addition, indicate major differences in re-irradiation sensitivity. The UBR investigations revealed a significant difference in fluence rate sensitivity between the ASTM A 302-B reference plate and a submerged-arc (S/A) Linde 80 weld. Studies of the Gundremmingen reactor vessel, representing a joint USA-FRG-UK undertaking revealed an anomaly in strong vs. weak test orientation radiation sensitivity. (orig./HP)

  20. The effects of environmental factors and experimental method on the results of low dose rate microprocessor irradiation tests

    Energy Technology Data Exchange (ETDEWEB)

    Laviron, A; Gerard, G [Commissariat a l' Energie Atomique, IPSN, Centre d' Etudes de Valduc, Is-sur-Tille (France); Gauthier, G; Henry, J Y; Le Meur, M [Commissariat a l' Energie Atomique, IPSN, Fontenay-aux-Roses (France)

    1992-02-01

    As part of the safety studies of nuclear facilities, a series of experiments have been in progress over a number of years to determine the principal parameters for which allowance needs to be made in the testing of microprocessors in low dose rate nuclear irradiation environments. This paper contains a brief description of the results already published, followed by a review of the latest results obtained, specifically as concerns the effects of temperature, the origin of the batch, the angle of incidence of the radiation and the test routine used. (author)

  1. Role of endovascular treatment in vascular injuries

    International Nuclear Information System (INIS)

    Tahir, M.M.; Haq, T.U.

    2012-01-01

    Objective: To evaluate retrospectively the results, complications and follow-up of patients after endovascular treatment of vascular injuries. Methods: Fifty transcatheter embolisation procedures (TCE) were performed in 46 patients between 1999 and 2008 at the Aga Khan University Hospital, Karachi. Injuries in 14 (30.4%) patients were due to road traffic accident; iatrogenic in 13 (28%); accidental in 6 (13%). Firearms, bomb blasts and earthquake contributed to injuries in 8(17%), 4(8.8%) and 1(2.2%) patients respectively. All patients underwent angiography and had evidence of either active haemorrhage, pseudo-aneurysm, abnormal vascularity or arteriovenous fistula. Follow-up ranged from 1 day to 6 years with mean of 10.5 months. Medical record files, lab results and imaging reports were utilised for the study. Procedure was declared as technically successful when there was cessation of extravasation, occlusion of fistula or exclusion of pseudo-aneurysm in the post-embolisation angiograms. Treatment was deemed clinically successful if there was resolution of the indication for which the procedure was done. Results: Transcatheter embolisation was technically successful in occluding vascular lesions in all 46 (100%) patients. Lesions recurred in 4 (9%) patients who underwent initially successful TCE. These patients were treated effectively with repeated TCE. Three patients died during the same hospital stay and 3 patients died after being discharged from the hospital. All these patients were treated successfully with TCE and had factors other then TCE contributing to their mortality. Conclusion: Transcatheter embolisation for vascular injuries was found to be a satisfactory procedure, with low morbidity and mortality rates. (author)

  2. Actual review of diagnostics and endovascular therapy of intracranial arterial stenoses; Diagnostik und endovaskulaere Therapie intrakranieller arterieller Stenosen

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, E.R. [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie; Weber, R. [Universitaetsklinikum Essen (Germany). Klinik fuer Neurologie; Forsting, M. [Universitaetsklinikum Giessen und Marburg, Giessen (Germany). Abt. fuer Neuroradiologie

    2011-02-15

    Approximately 6 - 50 % of all ischemic strokes are caused by intracranial arterial stenosis (IAS). Despite medical prevention, patients with symptomatic IAS have a high annual risk for recurrent ischemic stroke of about 12 %, and up to 19 % in the case of high-grade IAS ({>=} 70 %). Digital subtraction angiography remains the gold standard for the diagnosis and grading of IAS. However, noninvasive imaging techniques including CT angiography, MR angiography, or transcranial Doppler and duplex ultrasound examinations are used in the clinical routine to provide additional information about the brain structure and hemodynamic. However, for technical reasons, the grading of stenoses is sometimes difficult and inaccurate. To date, aspirin is recommended as the treatment of choice in the prevention of recurrent ischemic stroke in patients with IAS. IAS patients who suffer a recurrent ischemic stroke or transient ischemic attack while taking aspirin can be treated with endovascular stenting or angioplasty in specialized centers. The periprocedural complication rate of these endovascular techniques is about 2 - 7 % at experienced neuro-interventional centers. The rate of re-stenosis is reported between 10 and 40 % depending on patient age and stenosis location. Further randomized studies comparing medical secondary prevention and endovascular therapy are currently being performed. With regard to the improvement of endovascular methods and lower complication rates, the indication for endovascular therapy in IAS could be broadened especially for stenosis in the posterior circulation. (orig.)

  3. Emergent Endovascular Management of Acute Arterial Bleeding ...

    African Journals Online (AJOL)

    multiruka1

    little attention has been paid to the novel endovascular options available .... Fig 1b. Fig 1c. Figure 1a: Mass at gastric fundus enhanced in post contrast CT abdomen. ... 1c: Left gastric artery super selectively coiled to occlusion. Fig 2a. Fig 2b.

  4. Endovascular Treatment of an Aortobronchial Fistula

    International Nuclear Information System (INIS)

    Numan, Fueruezan; Arbatli, Harun; Yagan, Naci; Demirsoy, Ergun; Soenmez, Binguer

    2004-01-01

    A 67-year-old man operated on 8 years previously for type B aortic dissection presented with two episodes of massive hemoptysis. An aortobronchial fistula was suspected with spiral computed tomography angiography, and showed a small pseudoaneurysm corresponding to the distal anastomotic site. The patient underwent endovascular stent-graft implantation and is asymptomatic 8 months after the procedure

  5. Carotid artery revascularization : Surgical and endovascular developments

    NARCIS (Netherlands)

    Borst, G.J. de

    2007-01-01

    Carotid artery revascularization. Surgical and endovascular developments. Stroke is among the most disabling chronic diseases and the third major cause of death in the Western world. In the Netherlands around 12 per 1000 inhabitants suffers a stroke, and in 2005 over 10.000 people died as a result

  6. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    International Nuclear Information System (INIS)

    Boreham, D.R.; Dolling, J.-A.; Maves, S.R.; Siwarungsun, N.; Mitchel, R.E.J.

    2000-01-01

    We have compared dose-rate effects for γ-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  7. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Boreham, D.R.; Dolling, J.-A.; Maves, S.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Siwarungsun, N. [Chulalongkorn Univ., Bangkok (Thailand); Mitchel, R.E.J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2000-07-01

    We have compared dose-rate effects for {gamma}-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  8. High-dose-rate afterloading intracavitary irradiation and expandable metallic biliary endoprosthesis for malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, Hitoshi; Ohishi, Hajime; Yoshioka, Tetsuya [Nara Medical Univ., Kashihara (Japan); and others

    1989-04-01

    A double lumen catheter was developed as an applicator for the remote afterloading system (RALS) of {sup 60}Co for the intracavitary irradiation of an obstructed common bile duct due to gallbladder cancer in 1 case and by cholangiocarcinoma in 7 cases. This was followed by the biliary endoprosthesis with expandable metallic stents to maintain patency. The mean survival period after treatment was not long (14 weeks). However, removal of the external drainage tube was possible in 7 of the 8 cases, and none of the 8 cases showed dislodgement or deformity of the stent, or obstruction of the bile duct in the stent-inserted area. This combination effectively provided palliation, and has considerable potential for malignant biliary obstruction. (author).

  9. Electron-ion collision rates in atomic clusters irradiated by femtosecond laser pulses

    International Nuclear Information System (INIS)

    Moll, M; Hilse, P; Schlanges, M; Bornath, Th; Krainov, V P

    2010-01-01

    In atomic clusters irradiated by femtosecond laser pulses, plasmas with high density and high temperature are created. The heating is mainly caused by inverse bremsstrahlung, i.e. determined by electron-ion collisions. In the description of the scattering of electrons on noble gas ions in such plasmas, it is important to account for the inner structure of the ions and the screening by the surrounding plasma medium which can be accomplished by using suitable model potentials. In the wide parameter range met in experiments, the Born approximation is not applicable. Instead, the electron-ion collision frequency is calculated on the basis of classical momentum transport cross sections. Results are presented for xenon, krypton and argon ions in different charge states. A comparison of these results to those for the scattering on Coulomb particles with the same charge shows an enhancement of the collision frequency. The Born approximation, however, leads to an overestimation.

  10. Late type III endoleak after thoracic endovascular aneurysm repair and previous infrarenal stent graft implantation - a case report and review of the literature.

    Science.gov (United States)

    Leszczyński, Jerzy; Macioch, Waldemar; Chudziński, Witold; Gałązka, Zbigniew

    2017-09-01

    Thoracic endovascular aortic repair (TEVAR) effectively improved the results of thoracic aortic aneurysm treatment. TEVAR is a less invasive procedure that can be performed under local anesthesia with shorter hospital stay. The perioperative morbidity and mortality rates are lower for endovascular than open repair, but the rate of secondary interventions is higher for TEVAR. We report a case of an elderly man with synchronous abdominal and thoracic aortic aneurysms. A type III dangerous endoleak was recognized 3 years after TEVAR. It was successfully repaired during an endovascular procedure. There were no new endoleaks after 12 months of follow-up. TEVAR may be the only option of treatment for risky and elderly patients. However, postoperative monitoring is necessary to exclude different types of endoleaks. Most of them undergo effective endovascular repair.

  11. Unstable patients with retroperitoneal vascular trauma: an endovascular approach.

    Science.gov (United States)

    Boufi, Mourad; Bordon, Sébastien; Dona, Bianca; Hartung, Olivier; Sarran, Anthony; Nadeau, Sébastien; Maurin, Charlotte; Alimi, Yves S

    2011-04-01

    In hemodynamically unstable patients, the management of retroperitoneal vascular trauma is both difficult and challenging. Endovascular techniques have become an alternative to surgery in several trauma centers. Between 2004 and 2006, 16 patients (nine men, mean age: 46 years, range: 19-79 years) with retroperitoneal vascular trauma and hemodynamic instability were treated using an endovascular approach. The mean injury severity score was 30.7 ± 13.1. Mean systolic blood pressure and the shock index were 74 mm Hg and 1.9, respectively. Vasopressor drugs were required in 68.7% of cases (n = 11). Injuries were attributable to road traffic accidents (n = 15) and falls (n = 1). The hemorrhage sites included the internal iliac artery or its branches (n = 12) with bilateral injury in one case, renal artery (n = 2), abdominal aorta (n = 1), and lumbar artery (n = 1). In all, 14 coil embolizations and three stent-grafts were implanted. The technical success rate was 75%, as early re-embolization was necessary in one case and three patients died during the perioperative period. Six patients died during the period of hospitalization (37.5%). No surgical conversion or major morbidity was reported. In comparison with particulates, coil ± stent-graft may provide similar efficacy with regard to survival, and thus may be a valuable solution when particulate embolization is not available or feasible. Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

  12. Advances in endovascular aneurysm treatment: are we making a difference?

    International Nuclear Information System (INIS)

    Katz, Jeffrey M.; Ougorets, Igor; Tsiouris, Apostolos J.; Biondi, Alessandra; Salvaggio, Kimberly A.; Gobin, Y. Pierre; Stieg, Philip E.; Riina, Howard A.

    2005-01-01

    Recent advancements in endovascular aneurysm repair, including bioactive and expansile coils and intracranial stents, hold promise for improved aneurysm occlusion rates. We report the immediate and midterm clinical and angiographic outcomes of a consecutive series of patients treated since the advent of these technologies. Clinical and radiological records of 134 patients with 142 aneurysms treated between 2001 and 2004 were retrospectively evaluated by an independent neurologist. Endovascular procedures were analyzed by an independent neuroradiologist blinded to all clinical information. Seventy-two ruptured and 60 un-ruptured saccular aneurysms, nine fusiform and one post-traumatic aneurysm were treated. Matrix coils were used in 53% of saccular aneurysms and HydroCoils in 13% of all aneurysms. Neuroform stents were deployed in 19% of aneurysms. Angiographic total or subtotal occlusion was achieved in 76% of cases and in 96% at last follow-up. Aneurysm recanalization was observed in 14% over a mean follow-up of 12 months, and 18% of aneurysms were retreated. Clinically relevant complications occurred in 6.0%, resulting in procedure-related morbidity of 0.6% and 0.6% mortality at 6 months. No aneurysm bled over a cumulative 1,347 months of observation. Newer embolization technologies can be exploited successfully even in more complex aneurysms with very low morbidity and mortality. (orig.)

  13. Effect of radiation dose rate and cyclophosphamide on pulmonary toxicity after total body irradiation in a mouse model

    International Nuclear Information System (INIS)

    Safwat, Akmal; Nielsen, Ole S.; El-Badawy, Samy; Overgaard, Jens

    1996-01-01

    Purpose: Interstitial pneumonitis (IP) is still a major complication after total body irradiation (TBI) and bone marrow transplantation (BMT). It is difficult to determine the exact role of radiation in this multifactorial complication, especially because most of the experimental work on lung damage was done using localized lung irradiation and not TBI. We have thus tested the effect of radiation dose rate and combining cyclophosphamide (CTX) with single fraction TBI on lung damage in a mouse model for BMT. Methods and Materials: TBI was given as a single fraction at a high dose rate (HDR, 0.71 Gy/min) or a low dose rate (LDR, 0.08 Gy/min). CTX (250 mg/kg) was given 24 h before TBI. Bone marrow transplantation (BMT) was performed 4-6 h after the last treatment. Lung damage was assessed using ventilation rate (VR) and lethality between 28 and 180 days (LD (50(28))-180 ). Results: The LD 50 for lung damage, ± standard error (SE), increased from 12.0 (± 0.2) Gy using single fraction HDR to 15.8 (± 0.6) Gy using LDR. Adding CTX shifted the dose-response curves towards lower doses. The LD 50 values for the combined treatment were 5.3 (± 0.2) and 3.5 (± 0.2) Gy for HDR and LDR, respectively. This indicates that the combined effect of CTX and LDR was more toxic than that of combined CTX and HDR. Lung damage evaluated by VR demonstrated two waves of VR increase. The first wave of VR increase occurred after 6 weeks using TBI only and after 3 weeks in the combined CTX-TBI treatment, irrespective of total dose or dose rate. The second wave of VR elevation resembled the IP that follows localized thoracic irradiation in its time of occurrence. Conclusions: Lung damage following TBI could be spared using LDR. However, CTX markedly enhances TBI-induced lung damage. The combination of CTX and LDR is more toxic to the lungs than combining CTX and HDR

  14. Corrosion product identification and relative rates of corrosion of candidate metals in an irradiated air-steam environment

    International Nuclear Information System (INIS)

    Reed, D.T.; Swayambunathan, V.; Tani, B.S.; Van Konynenburg, R.A.

    1989-01-01

    Previously reported work by others indicates that dicopper trihydroxide nitrate, Cu 2 NO 3 (OH) 3 , forms on copper and copper alloys subjected to irradiated moist air near room temperature. We have performed experiments over a range of temperature and humidity, and have found that this species is formed at temperatures up to at least 150 degree C if low to intermediate relative humidities are present. At 150 degree C and 100% relative humidity, only Cu 2 O and CuO were observed. The relative general corrosion rates of the copper materials tested in 1-month experiments at dose rates of 0.7 and 2.0 kGy/h were Cu > 70/30 Cu--Ni > Al-bronze. High-nickel alloy 825 showed no observable corrosion. 29 refs., 4 tabs

  15. The mass effect model of the survival rate's dose effect of organism irradiated with low energy ion beam

    International Nuclear Information System (INIS)

    Shao Chunlin; Gui Qifu; Yu Zengliang

    1995-01-01

    The main characteristic of the low energy ions mutation is its mass deposition effect. Basing on the theory of 'double strand breaking' and the 'mass deposition effect', the authors suggests that the mass deposition products can repair or further damage the double strand breaking of DNA. According to this consideration the dose effect model of the survival rate of organism irradiated by low energy of N + ion beam is deduced as: S exp{-p[αφ + βφ 2 -Rφ 2 exp(-kφ)-Lφ 3 exp(-kφ)]}, which can be called 'mass effect model'. In the low energy ion beam mutation, the dose effects of many survival rates that can not be imitated by previous models are successfully imitated by this model. The suitable application fields of the model are also discussed

  16. Rate constant for reaction of vitamin C with protein radicals in γ-irradiated aqueous albumin solution at 295K

    International Nuclear Information System (INIS)

    Miyazaki, Tetsuo; Yoshimura, Toru; Mita, Kazuya; Suzuki, Keiji; Watanabe, Masami

    1995-01-01

    When an aqueous solution of albumin (0.1 kg dm -3 ) is irradiated by γ-rays at 295 K, albumin radicals with a long lifetime are observed by ESR. The reaction of vitamin C with the albumin radicals has been studied at 295 K in the albumin solution, which is considered as a model of cells. The rate constant for the reaction of vitamin C with the albumin radicals was measured as 0.014 dm 3 mol -1 S -1 , which is much smaller than the reported constants (10 6 -10 10 dm 3 mol -1 s -1 ) for the reaction of vitamin C with radicals in a dilute aqueous solution. The small rate constant for the reaction of vitamin C is ascribed to the reaction in polymer coils in the albumin solution, since vitamin C and albumin radicals diffuse very slowly in the coils. (author)

  17. Modeling low-dose-rate effects in irradiated bipolar-base oxides

    International Nuclear Information System (INIS)

    Graves, R.J.; Cirba, C.R.; Schrimpf, R.D.; Milanowski, R.J.; Saigne, F.; Michez, A.; Fleetwood, D.M.; Witczak, S.C.

    1997-02-01

    A physical model is developed to quantify the contribution of oxide-trapped charge to enhanced low-dose-rate gain degradation in BJTs. Simulations show that space charge limited transport is partially responsible for the low-dose-rate enhancement

  18. Short-term curative effect of endovascular stent-graft treatment for aortic diseases in China: a systematic review.

    Directory of Open Access Journals (Sweden)

    Siwen Wang

    Full Text Available INTRODUCTION: We analyzed the short-term efficacy of endovascular treatment for aortic diseases by summarizing all available published data on endovascular stent-graft treatment for abdominal aortic aneurysm (AAA, thoracic aortic aneurysm (TAA, type A aortic dissection (type A AD and type B aortic dissection (type B AD in China. METHODS: We performed a systematic analysis of 935 published series on retrograde endovascular treatment for aortic diseases in China from January 1996 to November 2010. Based on the inclusion criteria, 159 studies, involving a total of 5531 patients, were included. RESULTS: There were no significant differences in procedural success among the studies (P>0.05. The rates of overall neurologic complications and stroke were significantly different in all two-group comparisons (P0.05. A significant difference was noted between the 30-day mortality rate of the type A AD patients and the AAA or type B AD patients (P<0.05. CONCLUSION: Endovascular stent-graft is a feasible and safe treatment for aortic diseases, with high procedural success and low incidences of post-procedural complications and short-term mortality. Endovascular treatment for AAA and type B AD is more efficient than for type A AD and TAA.

  19. Effect of endovascular treatment on nitric oxide and renal function in Takayasu's arteritis with renovascular hypertension.

    Science.gov (United States)

    Parildar, Zuhal; Gulter, Ceyda; Parildar, Mustafa; Oran, Ismail; Erdener, Dilek; Memis, Ahmet

    2002-01-01

    Renal involvement in Takayasu's arteritis (TA) effects the disease outcome and endovascular treatment is an effective treatment of choice. We investigated nitric oxide (NO) levels and the effect of endovascular treatment in renovascular hypertensive TA patients. In five hypertensive patients with renal artery stenosis due to TA, serum creatinine, nitrite, nitrate; urinary microalbumin, nitrite, nitrate measurements and blood pressures were recorded at entry and after 24 h and 6 weeks of endovascular treatment. Serum NO levels were higher in patients than controls (p = 0.008). Serum and urine NO levels increased 24 h after the treatment and decreased after 6 weeks (p = 0.015; p = 0.01, respectively). After the treatment blood pressures decreased. Urinary microalbumin excretions increased after the intervention (p = 0.02) and returned to normal in patients 1 and 4, and decreased in the others. There were no significant differences in estimated glomerular filtration rate (EGFR), serum creatinine, urinary sodium and potassium levels. Increased NO secretion in these patients may contribute to improve the prognosis of renal function through its vasodilator and antiproliferative activities possibly by counterbalancing the excessive vasoconstrictor actions. Endovascular treatment causes a dilatation-induced shear stress that may be responsible for the increased NO release, which in turn leads to the rapid hypotensive response. Copyright 2002 S. Karger AG, Basel

  20. Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial

    Science.gov (United States)

    Braithwaite, Bruce; Cheshire, Nicholas J.; Greenhalgh, Roger M.; Grieve, Richard; Hassan, Tajek B.; Hinchliffe, Robert; Howell, Simon; Moore, Fionna; Nicholson, Anthony A.; Soong, Chee V.; Thompson, Matt M.; Thompson, Simon G.; Ulug, Pinar; Heatley, Francine; Anjum, Aisha; Kalinowska, Gosia; Sweeting, Michael J.; Thompson, Simon G.; Gomes, Manuel; Grieve, Richard; Powell, Janet T.; Ashleigh, Ray; Gomes, Manuel; Greenhalgh, Roger M.; Grieve, Richard; Hinchliffe, Robert; Sweeting, Michael; Thompson, Matt M.; Thompson, Simon G.; Ulug, Pinar; Roberts, Ian; Bell, Peter R. F.; Cheetham, Anne; Stephany, Jenny; Warlow, Charles; Lamont, Peter; Moss, Jonathan; Tijssen, Jan; Braithwaite, Bruce; Nicholson, Anthony A.; Thompson, Matthew; Ashleigh, Ray; Thompson, Luke; Cheshire, Nicholas J.; Boyle, Jonathan R.; Serracino-Inglott, Ferdinand; Thompson, Matt M.; Hinchliffe, Robert J.; Bell, Rachel; Wilson, Noel; Bown, Matt; Dennis, Martin; Davis, Meryl; Ashleigh, Ray; Howell, Simon; Wyatt, Michael G.; Valenti, Domenico; Bachoo, Paul; Walker, Paul; MacSweeney, Shane; Davies, Jonathan N.; Rittoo, Dynesh; Parvin, Simon D.; Yusuf, Waquar; Nice, Colin; Chetter, Ian; Howard, Adam; Chong, Patrick; Bhat, Raj; McLain, David; Gordon, Andrew; Lane, Ian; Hobbs, Simon; Pillay, Woolagasen; Rowlands, Timothy; El-Tahir, Amin; Asquith, John; Cavanagh, Steve; Dubois, Luc; Forbes, Thomas L.; Ashworth, Emily; Baker, Sara; Barakat, Hashem; Brady, Claire; Brown, Joanne; Bufton, Christine; Chance, Tina; Chrisopoulou, Angela; Cockell, Marie; Croucher, Andrea; Dabee, Leela; Dewhirst, Nikki; Evans, Jo; Gibson, Andy; Gorst, Siobhan; Gough, Moira; Graves, Lynne; Griffin, Michelle; Hatfield, Josie; Hogg, Florence; Howard, Susannah; Hughes, Cían; Metcalfe, David; Lapworth, Michelle; Massey, Ian; Novick, Teresa; Owen, Gareth; Parr, Noala; Pintar, David; Spencer, Sarah; Thomson, Claire; Thunder, Orla; Wallace, Tom; Ward, Sue; Wealleans, Vera; Wilson, Lesley; Woods, Janet; Zheng, Ting

    2015-01-01

    Aims To report the longer term outcomes following either a strategy of endovascular repair first or open repair of ruptured abdominal aortic aneurysm, which are necessary for both patient and clinical decision-making. Methods and results This pragmatic multicentre (29 UK and 1 Canada) trial randomized 613 patients with a clinical diagnosis of ruptured aneurysm; 316 to an endovascular first strategy (if aortic morphology is suitable, open repair if not) and 297 to open repair. The principal 1-year outcome was mortality; secondary outcomes were re-interventions, hospital discharge, health-related quality-of-life (QoL) (EQ-5D), costs, Quality-Adjusted-Life-Years (QALYs), and cost-effectiveness [incremental net benefit (INB)]. At 1 year, all-cause mortality was 41.1% for the endovascular strategy group and 45.1% for the open repair group, odds ratio 0.85 [95% confidence interval (CI) 0.62, 1.17], P = 0.325, with similar re-intervention rates in each group. The endovascular strategy group and open repair groups had average total hospital stays of 17 and 26 days, respectively, P < 0.001. Patients surviving rupture had higher average EQ-5D utility scores in the endovascular strategy vs. open repair groups, mean differences 0.087 (95% CI 0.017, 0.158), 0.068 (95% CI −0.004, 0.140) at 3 and 12 months, respectively. There were indications that QALYs were higher and costs lower for the endovascular first strategy, combining to give an INB of £3877 (95% CI £253, £7408) or €4356 (95% CI €284, €8323). Conclusion An endovascular first strategy for management of ruptured aneurysms does not offer a survival benefit over 1 year but offers patients faster discharge with better QoL and is cost-effective. Clinical trial registration ISRCTN 48334791. PMID:25855369

  1. Endovascular Procedures in Treatment of Infrapopliteal Arterial Occlusive Disease: Single Center Experience With 69 Infrapopliteal Procedures.

    Science.gov (United States)

    Janko, Pasternak J; Nebojsa, Budakov B; Andrej, Petres V

    2018-03-01

    Peripheral arterial occlusive disease (PAD) includes acute and chronic disorders of the blood supply as a result of obstruction of blood flow in the arteries of the limb. Treatment of PAD can be conservative, surgical and endovascular. Percutaneous transluminal angioplasty with or without stenting has become a recognized method, which is increasingly used in treatment of arterial occlusive disease. This study aimed to determine early results of endovascular treatment of critical limb ischemia (CLI) patients with infrapopliteal lesions. The study included 69 patients (46 men; mean age 65 years, range 38-84) with CLI (class 4 to 6 according to Rutherford). The primary study endpoints were absence of major amputation of the target limb at 6 months and occurance of local and systemic complications specifically related to use of endovascular treatment. Major amputation was avoided in 61 patients. Through 6 months, 6 patients underwent additional revascularization. One local complication (clinicaly significant dissection of popliteal artery) occurred, and it was resolved by stent implantation. There were no cases of systemic complications and death during the follow-up period. Rates of major amputation were 12.3% for diabetics versus 8.3% for non-diabetics. Our data showed that endovascular treatment of infrapopliteal disease is an effective and safe treatment in patients experiencing CLI, provides high limb preservation and low complication rates. Study outcomes support endovascular treatment as a primary option for patients experiencing CLI due to below the knee (BTK) occlusive disease. © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  2. The impact of hybrid neurosurgeons on the outcomes of endovascular coiling for unruptured cerebral aneurysms

    Science.gov (United States)

    Bekelis, Kimon; Gottlieb, Dan; Labropoulos, Nicos; Su, Yin; Tzoumakaris, Stavropoula; Jabbour, Pasqual; MacKenzie, Todd A.

    2017-01-01

    Background The impact of combined practices on the outcomes of unruptured cerebral aneurysm coiling remains an issue of debate. We investigated the association of combined open and endovascular expertise with the outcomes of unruptured cerebral aneurysm coiling. Methods We performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who underwent endovascular coiling for unruptured cerebral aneurysms from 2007 to 2012. In order to control for confounding we used propensity score conditioning, with mixed effects to account for clustering at the HRR level. Results During the study period, there were 11,716 patients, who underwent endovascular coiling for unruptured cerebral aneurysms, and met the inclusion criteria. Of these, 1,186 (10.1%) underwent treatment by hybrid neurosurgeons, and 10,530 (89.9%) by proceduralists who performed only endovascular coiling. Multivariable regression analysis with propensity score adjustment demonstrated lack of association of combined practice with 1-year postoperative mortality (OR, 0.84; 95% CI, 0.58–1.23), discharge to rehabilitation (OR, 1.0; 95% CI, 0.66–1.51), 30-day readmission rate (OR, 1.07; 95% CI, 0.83–1.38) and length of stay (LOS) (adjusted difference, 0.41; 95% CI, −0.26 to 1.09). Higher procedural volume was independently associated with improved outcomes. Conclusions In a cohort of Medicare patients, we did not demonstrate a difference in mortality, discharge to rehabilitation, readmission rate, and LOS between hybrid neurosurgeons, and proceduralists only performing endovascular coiling. Funding Supported by grants from the National Institute on Aging (PO1- AG19783), the National Institutes of Health Common Fund (U01-AG046830), and the National Center for Advancing Translational Sciences (NCATS) of the NIH (Dartmouth Clinical and Translational Science Institute-UL1TR001086). The funders had no role in the design or execution of the study. PMID:26918479

  3. Predictors of Reintervention After Endovascular Repair of Isolated Iliac Artery Aneurysm

    International Nuclear Information System (INIS)

    Zayed, Hany A.; Attia, Rizwan; Modarai, Bijan; Clough, Rachel E.; Bell, Rachel E.; Carrell, Tom; Sabharwal, Tarun; Reidy, John; Taylor, Peter R.

    2011-01-01

    The objective of this study was to identify factors predicting the need for reintervention after endovascular repair of isolated iliac artery aneurysm (IIAA). We reviewed prospectively collected database records of all patients who underwent endovascular repair of IIAA between 1999 and 2008. Detailed assessment of the aneurysms was performed using computed tomography angiography (CTA). Follow-up protocol included CTA at 3 months. If this showed no complication, then annual duplex scan was arranged. Multivariate analysis and analysis of patient survival and freedom from reintervention were performed using Kaplan–Meier life tables. Forty IIAAs (median diameter 44 mm) in 38 patients were treated (all men; median age 75 years), and median follow-up was 27 months. Endovascular repair of IIAA was required in 14 of 40 aneurysms (35%). The rate of type I endoleak was significantly higher with proximal landing zone (PLZ) diameter >30 mm in the aorta or >24 mm in the common iliac artery or distal landing zone (DLZ) diameter >24 mm (P = 0.03, 0.03, and 0.0014, respectively). Reintervention rate (RR) increased significantly with increased diameter or decreased length of PLZ; increased DLZ diameter; and endovascular IIAA repair (P = 0.005, 0.005, 0.02, and 0.02 respectively); however, RR was not significantly affected by length of PLZ or DLZ. Freedom-from-reintervention was 97, 93, and 86% at 12, 24, and 108 months. There was no in-hospital or aneurysm-related mortality. Endovascular IIAA repair is a safe treatment option. Proper patient selection is essential to decrease the RR.

  4. Contemporary economic and clinical evaluations of endovascular repair for intact descending thoracic aortic aneurysms.

    Science.gov (United States)

    Silingardi, Roberto; Gennai, Stefano; Coppi, Giovanni; Chester, Johanna; Marcheselli, Luigi; Brunetti, Massimo

    2017-12-01

    The aim of this study was to assess clinical and contemporary costs associated with elective endovascular repair of intact descending thoracic aortic aneurysms (DTAA) into the mid-term follow-up. A retrospective review of a prospectively maintained clinical database including 29 consecutive patients from July 2005 to December 2009 treated with elective endovascular repair (TEVAR) or TEVAR and surgical infrarenal repair (hybrid) of intact DTAA was performed. Mean age was 74.5 years old (±7.1). Primary clinical endpoints include mortality and major morbidity. Additionally a comprehensive economic appraisal of individual in-hospital and follow-up costs was executed. Economic endpoints include in-hospital and follow-up costs and patient discharge status. Elective endovascular and open repairs' clinical and economical outcomes in contemporary literature were assessed for comparison according to PRISMA standards. Immediate mortality was 6.9% (1/24 TEVAR and 1/5 hybrid). Three respiratory complications were recorded (11%; 2 TEVAR, 1 hybrid). Renal and cardiac complication rates were 7.4% (1 TEVAR, 1 hybrid) and 3.7% (1 TEVAR) respectively. Routine discharge home was achieved for 85% of patients (95.7% TEVAR, 25% hybrid). Three endoleaks were treated throughout the follow-up (2 TEVAR, 1 hybrid; mean 30.4 mo, ±19.9) rendering an 11% (3/27) reintervention rate. Average immediate cost was €21,976.87 for elective endovascular repair and €33,783.21 for elective endovascular hybrid repair. Additional reintervention and routine follow-up costs augmented immediate costs by 12.4%. This study supports satisfying immediate clinical outcomes for TEVAR and TEVAR+surgical infrarenal procedures. Although limited by a small population size and difficulties in economic comparisons, this study presents the real world social and economic cost scenario for both elective TEVAR and TEVAR hybrid treatment of DTAA of both the in-hospital and at mid term follow-up periods.

  5. Clinical outcome after endovascular coil embolization in elderly patients with subarachnoid hemorrhage

    International Nuclear Information System (INIS)

    Johansson, M.; Cesarini, K.G.; Ronne-Engstroem, E.; Enblad, P.; Norbaeck, O.; Gal, G.; Tovi, M.; Solander, S.; Contant, C.F.

    2004-01-01

    Subarachnoid hemorrhage (SAH) is not an unusual disease in an elderly population. The clinical outcome has improved over time. It has been suggested that elderly SAH patients would benefit from endovascular aneurysm treatment. The aim of this study was to evaluate technical results and clinical outcome in a series of elderly SAH-patients treated with endovascular coil embolization. Sixty-two patients (≥ 65 years) presenting with aneurysmal SAH underwent early endovascular coil embolization at Uppsala University Hospital between September 1996 and December 2000. In all 62 cases included in the study, endovascular coil embolization was considered the first line of treatment. Admission variables, specific information on technical success, degree of occlusion and procedural complications, and outcome figures were recorded. Clinical grade on admission was Hunt and Hess (H and H) I-II in 39%, H and H III in 27% and H and H IV-V in 34% of the patients. The proportion of posterior circulation aneurysms was 24%. Coil embolization was successfully completed in 94%. The degree of occlusion of the treated aneurysm was complete occlusion in 56%, neck remnant in 21%, residual filling in 11%, other remnant in 5% and not treated in 6%. The rate of procedural complications was 11%. Outcome after 6 months was favorable in 41%, severe disability in 36% and poor in 22%. Favorable outcome was achieved in 57% of the H and H I-II patients, 47% of the H and H III patients and 17% of the H and H IV-V patients. Endovascular aneurysm treatment can be performed in elderly patients with SAH with a high level of technical success, acceptable aneurysm occlusion results, an acceptable rate of procedural complications and fair outcome results. (orig.)

  6. Dose rate effect of 125I irradiation on normal rabbit eyes and experimental choroidal melanoma

    International Nuclear Information System (INIS)

    Yang, C.M.; Olsen, K.R.; Schwade, J.G.; Houdek, P.V.; Markoe, A.M.; Pisciotta, V.; Xiaodong Wu

    1993-01-01

    The dose rate effect of radiation by 125 I plaque on choroidal melanoma and normal intraocular tissue was studied. In the first part of the experiment, high activity plaques (HAP) and low activity plagues (LAP) were implanted on rabbit eyes with experimental Greene choroidal melanoma to deliver a total dose of 10 000 cGy to the tumor apex. The mean dose rate calculated at 0.5 mm from the inner sclera in eight eyes with high activity plaques was 3341.5 cGy hr -1 while that in ten eyes with low activity plaques was 239.9 cGy hr -1 . For tumors less than 1.0 mm in height, both groups showed complete tumor regression at the tumor implantation site after plaque treatment. For tumours more than 1.0 mm in height, two out of two eyes in the low activity plaque group and one of four eyes in the high activity plaque group failed to show complete tumor regression. In the second part of the experiment, 125 I plaques were implanted on the sclera of 12 normal rabbits' eyes. Six received high dose rate plaque treatment, while the other six received low dose rate plaque treatment. Clinical and histologic examinations demonstrated more damaging effects to the normal chorioretinal tissues at the plaque implantation site in the high dose rate plaque group. These results suggest that high dose rate plaques are more effective than low dose rate plaques when tumor height is statistically controlled. (Author)

  7. Low dose-rate irradiation in the treatment of acute myelogenous leukaemia in first remission

    Energy Technology Data Exchange (ETDEWEB)

    Cattell, P A; Unwin, S F [Royal Marsden Hospital, Sutton (UK)

    1981-04-01

    Thirty-six patients with acute myelogenous leukaemia (AML) in first remission received sibling bone marrow transplants following cyclophosphamide and a single dose of 1000 rad total body irradiation (TBI). The preparation programme for a patient undergoing a bone marrow transplant is described. The aim of the cyclophosphamide and TBI is to eradicate all active bone marrow present in the patient and to reduce the immune response of the patient to the graft, thus preventing rejection. The cobalt unit and treatment box used for the TBI is described together with details of the planning for TBI including test doses on the patient. The procedure on the day of the 8 hour TBI treatment is then given. The likely reactions following the TBI and the graft are described. Of these transplanted patients, 64% remain alive, well and disease-free, nine of them for more than one year and one surviving more than three years. These results are a significant improvement on the results of AML treated with chemotherapy and immunotherapy.

  8. Improvement of a method for predicting failure rates of coated particles during irradiation

    International Nuclear Information System (INIS)

    Bongartz, K.

    1977-01-01

    A method for calculating the coating stress distribution resulting from the statistical spread of geometrical parameters in irradiated fuel particle batches has been developed by Gulden et al. The existing method utilizing coated particles is extended in two ways: 1. A more realistic treatment of the buffer layer is adopted, taking into account its physical properties. 2. A statistical distribution according to Weibull has been adopted for the silicon carbide layer strength. Calculations with both the new and the old assumptions were performed on one feed particle and one breed particle type. It is shown that the two modifications influence the results of the original method. It was found that the extension of the first assumption has no influence on the stress distribution and the fraction of breaking feed particles, but it changes the stress distribution of the breed particles significantly. The fraction of broken particles at end burnup is increased by a factor of approximately 10. The extension of the second assumption affects the fraction of broken feed as well as that of the breed particles. Depending on the Weibull parameter, m, the number of failed feed particles increases by a factor of 1.3 to 2; the corresponding factor for breed particles is between 3.5 and 60

  9. Comparative dosimetric study in the estimation of the dose rate of the Transelektro LGI-01 irradiator

    International Nuclear Information System (INIS)

    Carrasco A, H.; Urena N, F.F.

    2004-01-01

    The 60 Co TRANSELEKTRO, model LGI-0 1, Hungarian, is similar to the Canadian Gamma cell. The evaluation of the dose ratio in the geometric center of the exposition chamber of the LGI-0 1 is presented in this paper. In order to do this two types of dosimeters were used: the alanine, and the L8-C 1 red acrylic (Canadian). Three dosimeters of each type were irradiated at 1, 2, 3, 4, 5, 6, 7 and 8 h. The respective intensities and absorbencies were measured and used to determine the proper absorbed doses and the dose ratio. The results obtained with both dosimeters were compared with the ratio dose that was reported by the Secondary Laboratory of Dosimetric Calibration of the Metrology Department of the ININ, which used a ionization chamber for the calibration of the LGI-0 1. The alanine dosemeter showed a ± 1.3% dispersion while with the acrylic dosemeter the dispersion was of ± 3.2%, with respect to the value reported by the authorized Calibration Laboratory. This paper was also used to update the calibration table of the L8-C1 red acrylic. (Author)

  10. Ascertainment of the effect of differential growth rates of mutants on observed mutant frequencies in X-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Knaap, A.G.A.C.; Simons, J.W.I.M.

    1983-01-01

    As it is not known to what extent differential growth rates of induced mutants lead to over- and under-representation of mutants in treated populations and thereby affect the determination of mutant frequencies, the mutation induction in X-irradiated L5178Y mouse lymphoma cells was determined via two methods. The first method involves the standard protocol which may suffer from the effect of differential growth rates, while the second method is based upon the fluctuation test in which the differential growth rates can be actually measured. It appeared that the standard protocol led to a mutant frequency that was similar to the mutant frequency determined in the fluctuation test. Therefore, the standard protocol appears to lead to only a minor under-estimation if any. Substantial heterogeneity in growth rates of induced mutants was observed, but the mutants with a selective advantage appear largely to compensate for the mutants that are lost because of selective disadvantage. It was calculated that the chance for isolating the same mutant twice from a treated population had been increased 2.2-fold because of the observed differential growth rates. (orig./AJ)

  11. A comparison of larval density and low dose rate irradiation effects on amphibian body size at metamorphosis

    Energy Technology Data Exchange (ETDEWEB)

    Stark, K.; Scott, D.E.; Tsyusko, O.; Coughlin, D.P.; Hinton, T.G.

    2008-07-01

    Amphibian larvae undergo substantial morphological and physiological changes as they metamorphose into adults. This period of rapid change and enhanced cell division could increase their sensitivity to external stressors. In this study, we were interested in possible differences between natural and anthropogenic stressor effects during the period just prior to metamorphosis. We studied this by exposing late-stage Scaphiopus holbrookii tadpoles in different larval densities to four irradiation dose rates (0.13, 2.4, 21, and 222 mGy d-1) from 137Cs. Life history traits important for population dynamics, such as body size at metamorphosis and development rate, were measured. Results suggest that the ecological factor larval density had a much more profound effect on juvenile body size at metamorphosis than low-dose rate radiation. The development rate measured as age at metamorphosis was not effected by the two stressors. Radiation had no impact on the endpoints we measured; giving credence to the IAEA guidance that a dose rate smaller than 10 mGy d-1 is protective of aquatic biota. (author)(tk)

  12. A comparison of larval density and low dose rate irradiation effects on amphibian body size at metamorphosis

    International Nuclear Information System (INIS)

    Stark, K.; Scott, D.E.; Tsyusko, O.; Coughlin, D.P.; Hinton, T.G.

    2008-01-01

    Amphibian larvae undergo substantial morphological and physiological changes as they metamorphose into adults. This period of rapid change and enhanced cell division could increase their sensitivity to external stressors. In this study, we were interested in possible differences between natural and anthropogenic stressor effects during the period just prior to metamorphosis. We studied this by exposing late-stage Scaphiopus holbrookii tadpoles in different larval densities to four irradiation dose rates (0.13, 2.4, 21, and 222 mGy d -1 ) from 137 Cs. Life history traits important for population dynamics, such as body size at metamorphosis and development rate, were measured. Results suggest that the ecological factor larval density had a much more profound effect on juvenile body size at metamorphosis than low-dose rate radiation. The development rate measured as age at metamorphosis was not effected by the two stressors. Radiation had no impact on the endpoints we measured; giving credence to the IAEA guidance that a dose rate smaller than 10 mGy d -1 is protective of aquatic biota. (author)(tk)

  13. Dose and dose rate effects of whole-body gamma-irradiation: I. Lymphocytes and lymphoid organs

    Science.gov (United States)

    Pecaut, M. J.; Nelson, G. A.; Gridley, D. S.

    2001-01-01

    The major goal of part I of this study was to compare varying doses and dose rates of whole-body gamma-radiation on lymphoid cells and organs. C57BL/6 mice (n = 75) were exposed to 0, 0.5, 1.5, and 3.0 Gy gamma-rays (60Co) at 1 cGy/min (low-dose rate, LDR) and 80 cGy/min (high-dose rate, HDR) and euthanized 4 days later. A significant dose-dependent loss of spleen mass was observed with both LDR and HDR irradiation; for the thymus this was true only with HDR. Decreasing leukocyte and lymphocyte numbers occurred with increasing dose in blood and spleen at both dose rates. The numbers (not percentages) of CD3+ T lymphocytes decreased in the blood in a dose-dependent manner at both HDR and LDR. Splenic T cell counts decreased with dose only in HDR groups; percentages increased with dose at both dose rates. Dose-dependent decreases occurred in CD4+ T helper and CD8+ T cytotoxic cell counts at HDR and LDR. In the blood the percentages of CD4+ cells increased with increasing dose at both dose rates, whereas in the spleen the counts decreased only in the HDR groups. The percentages of the CD8+ population remained stable in both blood and spleen. CD19+ B cell counts and percentages in both compartments declined markedly with increasing HDR and LDR radiation. NK1.1+ natural killer cell numbers and proportions remained relatively stable. Overall, these data indicate that the observed changes were highly dependent on the dose, but not dose rate, and that cells in the spleen are more affected by dose rate than those in blood. The results also suggest that the response of lymphocytes in different body compartments may be variable.

  14. Characterizing low dose and dose rate effects in rodent and human neural stem cells exposed to proton and gamma irradiation

    Directory of Open Access Journals (Sweden)

    Bertrand P. Tseng

    2013-01-01

    Full Text Available Past work has shown that exposure to gamma rays and protons elicit a persistent oxidative stress in rodent and human neural stem cells (hNSCs. We have now adapted these studies to more realistic exposure scenarios in space, using lower doses and dose rates of these radiation modalities, to further elucidate the role of radiation-induced oxidative stress in these cells. Rodent neural stem and precursor cells grown as neurospheres and human neural stem cells grown as monolayers were subjected to acute and multi-dosing paradigms at differing dose rates and analyzed for changes in reactive oxygen species (ROS, reactive nitrogen species (RNS, nitric oxide and superoxide for 2 days after irradiation. While acute exposures led to significant changes in both cell types, hNSCs in particular, exhibited marked and significant elevations in radiation-induced oxidative stress. Elevated oxidative stress was more significant in hNSCs as opposed to their rodent counterparts, and hNSCs were significantly more sensitive to low dose exposures in terms of survival. Combinations of protons and γ-rays delivered as lower priming or higher challenge doses elicited radioadaptive changes that were associated with improved survival, but in general, only under conditions where the levels of reactive species were suppressed compared to cells irradiated acutely. Protective radioadaptive effects on survival were eliminated in the presence of the antioxidant N-acetylcysteine, suggesting further that radiation-induced oxidative stress could activate pro-survival signaling pathways that were sensitive to redox state. Data corroborates much of our past work and shows that low dose and dose rate exposures elicit significant changes in oxidative stress that have functional consequences on survival.

  15. NPK, protein content and yield of broccoli as affected by gamma rays seeds irradiation and phosphorus fertilizer rates

    International Nuclear Information System (INIS)

    El-Desoki, S.A.; Abdallah, A.A.G.; Awad, S.M.; Aboel-Kheir, O.H.

    2005-01-01

    Two field experiments were carried out during 1999/2000 and 2000/2001 winter growing seasons at the experimental farm of Nuclear Research Center, Atomic Energy Authority, Inshas, Egypt. The experiments were conducted to study the effect of pre sowing-seeds irradiation with different doses of gamma rays (0, 2, 3 and 4 Gy) and different phosphorus fertilizer application rates, 0, 30, 60 and 90 k P 2 O 5 /fed) on NPK content of leaves and spear, and protein content in spears at maturity, spear diameter, main spear fresh and dry weight per plant, total spear fresh weight per plant and total spear yield. In general, exposing broccoli seeds to different gamma ray doses up to 4 Gy prior to sowing increased the above mentioned parameters with different magnitudes comparing with the non-irradiated control plants. The highest percentage of increase was obtained by exposing broccoli seeds to 3 Gy. There were non-significant differences between 3 and 4 Gy treatments during the two growing seasons. With respect to the effect of phosphorus fertilizer application rates on the studied parameters, increasing phosphorus application rates up to 90 kg P 2 O 5 /fed increased the above mentioned parameters. The highest percentage of increase was obtained by applying 90 kg P 2 O 5 /fed. The interaction, gamma ray and P level showed phosphorus there were significant differences in main spear fresh and dry weight per plant, total spear yield and spear diameter in first season. The highest value was obtained by 3 Gy and 90 kg P 2 O 5 /fed. Also there were significant effects on NPK content in broccoli leaves at 90 days after transplanting (DAT) except P in second season and nonsignificant values of broccoli spear at harvest except N, K in first season. The highest protein content of broccoli spears at harvest was obtained with 2 Gy and 30 kg P 25 /fed

  16. Emergency endovascular coiling of a ruptured giant splenic artery aneurysm

    DEFF Research Database (Denmark)

    Wernheden, Erika; Brenøe, Anne Sofie; Shahidi, Saeid

    2017-01-01

    Splenic artery aneurysms (SAAs) are the third most common abdominal aneurysm. Endovascular treatment of SAAs is preferred, and coiling is the most commonly used technique. Ruptured giant (>5 cm) SAAs are usually treated with open surgery including splenectomy. We present a rare case of a ruptured...... 15-cm giant SAA in an 84-year-old woman treated successfully with emergency endovascular coiling. To our knowledge, this is one of the few reports of emergency endovascular treatment for ruptured giant SAA....

  17. A study of survival rate of the patients with esophageal carcinoma treated by pre- and/or post-operative irradiation

    International Nuclear Information System (INIS)

    Eida, Koichiro

    1986-01-01

    So far there is still considerable disagreement as to the evaluation of the pre- and postoperative irradiation effects on the survival rate of the patients with esophageal carcinoma. From April 1973 to December 1983, 138 cases of thoracic esophageal carcinoma were surgically operated upon at our Department; 68 cases were irradiated and 70 cases were not irradiated prior to the surgical operation. Followup study was done and its result has been reported in this communication. A few cases treated by pre-operative irradiation survived longer than the expected longevity in spite of their low curative operation rates. Prognosis was better in the cases with well differentiated squamous cell carcinoma, when marked or good responses to pre-operative irradiation with the calculated total dose of 30 Gy were recorded. There were differences in responsibility in the various histological types of esophageal carcinomas; good response in the group of well differentiated squamous carcinoma, less marked response in the groups of moderately and poorly differentiated squamous carcinomas, minor response in the types of undifferentiated and unclassifed carcinomas. From our observation it seems reasonable to say that prognosis of the patients with pre- and postoperative irradiation was better than that of those who received postoperative irradiation only. (author)

  18. Effect of low dose rate irradiation on doped silica core optical fibers

    International Nuclear Information System (INIS)

    Friebele, E.J.; Askins, C.G.; Gingerich, M.E.

    1984-01-01

    The optical attenuation induced in multimode doped silica core optical fiber waveguides by a year's exposure to low dose rate (1 rad/day) ionizing radiation was studied, allowing a characterization of fibers deployed in these environments and a determination of the permanent induced loss in the waveguides. Variations in the induced attenuation at 0.85 μm have been observed with changes in the dose rate between 1 rad/day and 9000 rads/min. These dose rate dependences have been found to derive directly from the recovery that occurs during the exposure; the recovery data predict little or no dose rate dependence of the damage at 1.3 μm. The low dose rate exposure has been found to induce significant permanent attenuation in the 0.7-1.7-μm spectral region in all fibers containing P in the core, whether doped uniformly across the diameter or constrained to a narrow spike on the centerline. Whereas permanent loss was induced at 0.85 μm in a P-free binary Ge-doped silica core fiber by the year's exposure, virtually no damage was observed at 1.3 μm

  19. Relative effect of radiation dose rate on hemopoietic and nonhemopoietic lethality of total-body irradiation

    International Nuclear Information System (INIS)

    Peters, L.J.; McNeill, J.; Karolis, C.; Thames, H.D. Jr.; Travis, E.L.

    1986-01-01

    Experiments were undertaken to determine the influence of dose rate on the toxicity of total-body irrdiation (TBI) with and without syngeneic bone-marrow rescue in mice. The results showed a much greater dose-rate dependence for death from nonhemopoietic toxicity than from bone-marrow ablation, with the ratio of LD 50 's increasing from 1.73 at 25 cGy/min to 2.80 at 1 cGy/min. At the higher dose rates, dose-limiting nonhemopoietic toxicity resulted from late organ injury, affecting the lungs, kidneys, and liver. At 1 cGy/min the major dose-limiting nonhemopoietic toxicity was acute gastrointestinal injury. The implications of these results in the context of TBI in preparation for bone-marrow transplantation are discussed. 15 refs., 4 figs

  20. The effect of ultrasound irradiation on the convective heat transfer rate during immersion cooling of a stationary sphere.

    Science.gov (United States)

    Kiani, Hossein; Sun, Da-Wen; Zhang, Zhihang

    2012-11-01

    It has been proven that ultrasound irradiation can enhance the rate of heat transfer processes. The objective of this work was to study the heat transfer phenomenon, mainly the heat exchange at the surface, as affected by ultrasound irradiation around a stationary copper sphere (k=386W m(-1)K(-1), C(p)=384J kg(-1)K(-1), ρ=8660kg m(-3)) during cooling. The sphere (0.01m in diameter) was immersed in an ethylene glycol-water mixture (-10°C) in an ultrasonic cooling system that included a refrigerated circulator, a flow meter, an ultrasound generator and an ultrasonic bath. The temperature of the sphere was recorded using a data logger equipped with a T-type thermocouple in the center of the sphere. The temperature of the cooling medium was also monitored by four thermocouples situated at different places in the bath. The sphere was located at different positions (0.02, 0.04 and 0.06m) above the transducer surface of the bath calculated considering the center of the sphere as the center of the reference system and was exposed to different intensities of ultrasound (0, 120, 190, 450, 890, 1800, 2800, 3400 and 4100W m(-2)) during cooling. The frequency of the ultrasound was 25kHz. It was demonstrated that ultrasound irradiation can increase the rate of heat transfer significantly, resulting in considerably shorter cooling times. Higher intensities caused higher cooling rates, and Nu values were increased from about 23-27 to 25-108 depending on the intensity of ultrasound and the position of the sphere. However, high intensities of ultrasound led to the generation of heat at the surface of the sphere, thus limiting the lowest final temperature achieved. An analytical solution was developed considering the heat generation and was fitted to the experimental data with R(2) values in the range of 0.910-0.998. Visual observations revealed that both cavitation and acoustic streaming were important for heat transfer phenomenon. Cavitation clouds at the surface of the sphere

  1. Short vs prolonged dual antiplatelet treatment upon endovascular stenting of peripheral arteries

    Directory of Open Access Journals (Sweden)

    Kronlage M

    2017-10-01

    suffered a stroke/transient ischemic attack (P>0.05. In addition, there was no difference regarding mortality and amputation rate comparing short vs prolonged DAPT regime in a 12-month follow-up.Conclusion: In the current cohort, prolonged DAPT after endovascular stenting had no beneficial effect on the outcome in a 12-month follow-up. Keywords: peripheral artery disease, stent implantation, dual antiplatelet therapy, primary patency, endovascular therapy

  2. Endovascular treatment of spine and spinal cord lesions

    International Nuclear Information System (INIS)

    Berenstein, A.

    1992-01-01

    Completing this comprehensive series on endovascular interventional angiography, Volume 5 focuses on the vascular abnormalities of the spine and spinal cord. It is based on the detailed functional vascular anatomy described in Volume 3 and the principles and function of endovascular treatment described in Volumes 1-4. As in the companion volumes, the unique approach gives view of the disease itself, its anatomical features and its clinical presentation. The technical aspects of the interventional or endovascular neuroradiology are built upon the solid analysis of the disease and its angioarchitecture. The recent developments in endovascular procedures, such as aneurysm treatment, angioplasty, and vascular recanalizations, are reviewed. (orig.). 118 figs. in 442 separate illustrations

  3. Kinematics effectively delineate accomplished users of endovascular robotics with a physical training model.

    Science.gov (United States)

    Duran, Cassidy; Estrada, Sean; O'Malley, Marcia; Lumsden, Alan B; Bismuth, Jean

    2015-02-01

    Endovascular robotics systems, now approved for clinical use in the United States and Europe, are seeing rapid growth in interest. Determining who has sufficient expertise for safe and effective clinical use remains elusive. Our aim was to analyze performance on a robotic platform to determine what defines an expert user. During three sessions, 21 subjects with a range of endovascular expertise and endovascular robotic experience (novices 20 hours) performed four tasks on a training model. All participants completed a 2-hour training session on the robot by a certified instructor. Completion times, global rating scores, and motion metrics were collected to assess performance. Electromagnetic tracking was used to capture and to analyze catheter tip motion. Motion analysis was based on derivations of speed and position including spectral arc length and total number of submovements (inversely proportional to proficiency of motion) and duration of submovements (directly proportional to proficiency). Ninety-eight percent of competent subjects successfully completed the tasks within the given time, whereas 91% of noncompetent subjects were successful. There was no significant difference in completion times between competent and noncompetent users except for the posterior branch (151 s:105 s; P = .01). The competent users had more efficient motion as evidenced by statistically significant differences in the metrics of motion analysis. Users with >20 hours of experience performed significantly better than those newer to the system, independent of prior endovascular experience. This study demonstrates that motion-based metrics can differentiate novice from trained users of flexible robotics systems for basic endovascular tasks. Efficiency of catheter movement, consistency of performance, and learning curves may help identify users who are sufficiently trained for safe clinical use of the system. This work will help identify the learning curve and specific movements that

  4. Development of a PROficiency-Based StePwise Endovascular Curricular Training (PROSPECT) Program.

    Science.gov (United States)

    Maertens, Heidi; Aggarwal, Rajesh; Desender, Liesbeth; Vermassen, Frank; Van Herzeele, Isabelle

    2016-01-01

    Focus on patient safety, work-hour limitations, and cost-effective education is putting pressure to improve curricula to acquire minimally invasive techniques during surgical training. This study aimed to design a structured training program for endovascular skills and validate its assessment methods. A PROficiency-based StePwise Endovascular Curricular Training (PROSPECT) program was developed, consisting of e-learning and hands-on simulation modules, focusing on iliac and superficial femoral artery atherosclerotic disease. Construct validity was investigated. Performances were assessed using multiple-choice questionnaires, valid simulation parameters, global rating scorings, and examiner checklists. Feasibility was assessed by passage of 2 final-year medical students through this PROSPECT program. Ghent University Hospital, a tertiary clinical care and academic center in Belgium with general surgery residency program. Senior-year medical students were recruited at Ghent University Hospital. Vascular surgeons were invited to participate during conferences and meetings if they had performed at least 100 endovascular procedures as the primary operator during the last 2 years. Overall, 29 medical students and 20 vascular surgeons participated. Vascular surgeons obtained higher multiple-choice questionnaire scores (median: 24.5-22.0 vs. 15.0-12.0; p train cognitive, technical, and nontechnical endovascular skills was developed. A structured, stepwise, proficiency-based valid endovascular program to train cognitive, technical, and human factor skills has been developed and proven to be feasible. A randomized controlled trial has been initiated to investigate its effect on performances in real life, patient outcomes, and cost-effectiveness. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  5. Percutaneous Endovascular Radiofrequency Ablation for Malignant Portal Obstruction: An Initial Clinical Experience

    International Nuclear Information System (INIS)

    Wu, Tian-Tian; Li, Hu-Cheng; Zheng, Fang; Ao, Guo-Kun; Lin, Hu; Li, Wei-Min

    2016-01-01

    PurposeThe Habib™ VesOpen Catheter is a new endovascular radiofrequency ablation (RFA) device used to treat malignant portal obstruction. The purpose of this study was to evaluate the clinical feasibility and safety of RFA with this device.MethodsWe collected the clinical records and follow-up data of patients with malignant portal obstruction treated with percutaneous endovascular portal RFA using the Habib™ VesOpen Catheter. Procedure-related complications, improvement of symptoms, portal patency, survival, and postoperative biochemical tests were investigated.ResultsThe 31 patients enrolled in the study underwent 41 successful endovascular portal RFA procedures. Patients were divided into a portal-stenting (PS) group (n = 13), which underwent subsequent portal stenting with self-expandable metallic stents, and a non-stenting (NS) group (n = 18), which did not undergo stenting. No procedure-related abdominal hemorrhage or portal rupture occurred. Postablation complications included abdominal pain (n = 26), fever (n = 13), and pleural effusion (n = 15). Improvements in clinical manifestations were observed in 27 of the 31 patients. Of the 17 patients experiencing portal restenosis, 10 underwent successful repeat RFA. The rate of successful repeat RFA was significantly higher in the NS group than in the PS group. Median portal patency was shorter in the PS group than in the NS group. No mortality occurred during the 4 weeks after percutaneous endovascular portal RFA.ConclusionsPercutaneous endovascular portal RFA is a feasible and safe therapeutic option for malignant portal obstruction. Prospective investigations should be performed to evaluate clinical efficacy, in particular, the need to evaluate the necessity for subsequent portal stenting.

  6. Percutaneous Endovascular Radiofrequency Ablation for Malignant Portal Obstruction: An Initial Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tian-Tian, E-mail: matthewwu1979@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China); Li, Hu-Cheng, E-mail: hucheng-li-surgery@126.com [The 307th Hospital of PLA, General Surgery Department (China); Zheng, Fang, E-mail: fang-zheng-surgery@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China); Ao, Guo-Kun, E-mail: guokun-ao-radiology@126.com; Lin, Hu, E-mail: hu-lin-radiology@126.com [The 309th Hospital of PLA, Radiology Department (China); Li, Wei-Min, E-mail: weimin-li-surgery@126.com [The 309th Hospital of PLA, Hepatobiliary Surgery Department (China)

    2016-07-15

    PurposeThe Habib™ VesOpen Catheter is a new endovascular radiofrequency ablation (RFA) device used to treat malignant portal obstruction. The purpose of this study was to evaluate the clinical feasibility and safety of RFA with this device.MethodsWe collected the clinical records and follow-up data of patients with malignant portal obstruction treated with percutaneous endovascular portal RFA using the Habib™ VesOpen Catheter. Procedure-related complications, improvement of symptoms, portal patency, survival, and postoperative biochemical tests were investigated.ResultsThe 31 patients enrolled in the study underwent 41 successful endovascular portal RFA procedures. Patients were divided into a portal-stenting (PS) group (n = 13), which underwent subsequent portal stenting with self-expandable metallic stents, and a non-stenting (NS) group (n = 18), which did not undergo stenting. No procedure-related abdominal hemorrhage or portal rupture occurred. Postablation complications included abdominal pain (n = 26), fever (n = 13), and pleural effusion (n = 15). Improvements in clinical manifestations were observed in 27 of the 31 patients. Of the 17 patients experiencing portal restenosis, 10 underwent successful repeat RFA. The rate of successful repeat RFA was significantly higher in the NS group than in the PS group. Median portal patency was shorter in the PS group than in the NS group. No mortality occurred during the 4 weeks after percutaneous endovascular portal RFA.ConclusionsPercutaneous endovascular portal RFA is a feasible and safe therapeutic option for malignant portal obstruction. Prospective investigations should be performed to evaluate clinical efficacy, in particular, the need to evaluate the necessity for subsequent portal stenting.

  7. A Cs-137 afterloading device. Preliminary results of cell kinetic effects of low dose-rate irradiation in an experimental tumour

    International Nuclear Information System (INIS)

    Rutgers, D.H.

    1988-01-01

    A Cs-137 afterloading technique is described which can be used in experimental tumours. Preliminary results, obtained with the human cervical carcinoma ME-180 xenografted to nude athymic mice, demonstrated that 20 Gy of low dose-rate irradiation induced an important redistribution of cells over cell cycle. The proportion of cells in G2-phase increased from 14.4% to 44.2% at 140 hours after irradiation. This method allows an accurate calculation of the dose-rate distribution in the tumour. Investigations of the cell kinetic effects of low dose-rate irradiation, at different dose-rates and different total doses, are therefore facilitated by the technique. (orig.) [de

  8. DRAGON score predicts functional outcomes in acute ischemic stroke patients receiving both intravenous tissue plasminogen activator and endovascular therapy.

    Science.gov (United States)

    Wang, Arthur; Pednekar, Noorie; Lehrer, Rachel; Todo, Akira; Sahni, Ramandeep; Marks, Stephen; Stiefel, Michael F

    2017-01-01

    The DRAGON score, which includes clinical and computed tomographic (CT) scan parameters, predicts functional outcomes in ischemic stroke patients treated with intravenous tissue plasminogen activator (IV tPA). We assessed the utility of the DRAGON score in predicting functional outcome in stroke patients receiving both IV tPA and endovascular therapy. A retrospective chart review of patients treated at our institution from February 2009 to October 2015 was conducted. All patients with computed tomography angiography (CTA) proven large vessel occlusions (LVO) who underwent intravenous thrombolysis and endovascular therapy were included. Baseline DRAGON scores and modified Rankin Score (mRS) at the time of hospital discharge was calculated. Good outcome was defined as mRS ≤3. Fifty-eight patients with LVO of the anterior circulation were studied. The mean DRAGON score of patients on admission was 5.3 (range, 3-8). All patients received IV tPA and endovascular therapy. Multivariate analysis demonstrated that DRAGON scores ≥7 was associated with higher mRS ( P DRAGON scores ≤6. Patients with DRAGON scores of 7 and 8 on admission had a mortality rate of 3.8% and 40%, respectively. The DRAGON score can help predict better functional outcomes in ischemic stroke patients receiving both IV tPA and endovascular therapy. This data supports the use of the DRAGON score in selecting patients who could potentially benefit from more invasive therapies such as endovascular treatment. Larger prospective studies are warranted to further validate these results.

  9. Endovascular treatment of the subclavian artery aneurysm in high-risk patient - a single-center experience

    Directory of Open Access Journals (Sweden)

    Marjanović Ivan

    2016-01-01

    Full Text Available We present our first experience with endovascular treatment of 6 subclavian artery aneurysms (SAA occurring in five male and one female patient. All patients, in our studies, according to ASA classification were high risk for open repair of SAA. The etiology of the all aneurysms was atherosclerosis degeneration of the artery. Two aneurysms were of intrathoracic location, then the other were extrathoracic. Symptoms related to subclavian artery aneurysms were present in two patients, compression and chest pain in one, and hemorrhage shock in second, while the remaining patients were asymptomatic. We preferred the Viabhan endoprosthesis for endovascular repair in 5 cases. In one patient with ruptured of subclavian artery aneurysm who was high-risk for open repair we made combined endovascular procedure. First at all, we covered the origin of left subclavian artery with thoracic stent graft and after that we put two coils in proximal part of subclavian artery. There was no operative mortality, and the early patency rate was 100%. The follow-up period was from 3 months to 3 years. During this period, one patient died of heart failure and one patient required endovascular reoperation due to endoleak type I. Endovascular treatment is recommended for all patients with subclavian artery aneurysm whenever this is possible due to anatomical reasons especially in high-risk patient with intrathoracic localization of aneurysm, to prevent potential complications.

  10. Endovascular treatment of radiation-induced carotid blowout syndrome. Report of two cases

    International Nuclear Information System (INIS)

    Adachi, Akihiko; Kobayashi, Eiichi; Watanabe, Yoshiyuki; Yoneyama, Tomoko S.; Hayasaka, Michihiro; Suzuki, Homare; Okamoto, Yoshitaka; Saeki, Naokatsu

    2011-01-01

    Carotid Blowout Syndrome (CBS), or Carotid Artery Rupture (CAR), is a delayed complication with potentially fatal consequences occurring after the implementation of radiotherapy on head and neck tumors. In this report we describe two patients received endovascular treatment for severe hemorrhagic CBS developing 36 and 2 years, respectively, after radiotherapy. Both patients survived and responded positively to treatment. Case 1 was an 80-year-old woman found with minor hemorrhage near the bifurcation of the common carotid artery, 36 years after neck irradiation. She experienced frequent hemorrhagic events during the following years. Six years after the initial discovery of bleeding, she experienced massive hemorrhage, lapsed into shock, and was admitted to an Emergency Room. Connective tissue around the carotid artery was largely exposed due to neck skin defect. After hemorrhage was halted by manual compression, transient hemostasis was achieved with coil embolization of the aneurysm presumed to be the source of bleeding. Recurrent hemorrhage developed two weeks later with unraveled coil mass extrusion. Parent artery occlusion was performed by endovascular trapping, achieving permanent hemostasis. Case 2 presented massive nasal bleeding originating from the petrous segment of the internal carotid artery, 2 years after having been treated with heavy particle irradiation for olfactory neuroblastoma. Ischemic tolerance was confirmed by balloon occlusion test. Based on previous experiences, the bleeding was immediately halted by endovascular trapping. Both patients were subsequently discharged, free of new neurological symptoms. Emergent hemostatic treatment is required in CBS developing severe hemorrhage. However, within irradiation fields, temporal embolization devices hardly lead to complete resolution. This is due to the deteriorated condition of the vascular wall incapable to enduring the expansion power of coils, stents or balloons. Bypass grafting is also

  11. Impact of switched dose-rate irradiation on the response of the LM124 operational amplifier to pulsed X-rays

    International Nuclear Information System (INIS)

    Roche, N.J.H.; Dusseau, L.; Mekki, J.; Perez, S.; Gonzalez Velo, Y.; Boch, J.; Saigne, F.; Vaille, J.R.; Vaille, J.R.; Marec, R.; Calvel, P.; Bezerra, F.; Auriel, G.; Azais, B.; Buchner, S.P.

    2011-01-01

    The Synergistic effect between TID and ATREEs (Analog Transient Radiation Effects on Electronics) in an operational amplifier (opamp) (LM124) is investigated for three different bias configurations. An accelerated irradiation technique is used to study these synergistic effects. The impact of TID on ATREEs is found to be identical regardless of whether the irradiation is performed at low dose rate or whether the dose rate is switched from high to low using the Dose Rate Switching (DRS) technique. The correlation between the deviations of the opamp's electrical parameters and the changes of ATREE widths is clearly established. (authors)

  12. Endovascular treatment of very small intracranial aneurysms

    DEFF Research Database (Denmark)

    Iskandar, A; Nepper-Rasmussen, J

    2011-01-01

    to large aneurysms (> 3 mm). However the data also suggest that endovascular treatment of very small aneurysms might be associated with an increased risk of procedural ruptures and mortality. At nine-month follow-up results indicate significantly less compaction in the very small aneurysms....... endovascular treatment was attempted in 956 consecutive intracranial aneurysms. Of 956 aneurysms, 111 aneurysms were very small aneurysms with a maximal diameter of 3 mm or less. We conducted a retrospective analysis of angiographic and clinical outcome following coiling of very small aneurysms...... aneurysms and less than 90% aneurysm occlusion in six aneurysms. Complications occurred in the treatment of 15 aneurysms, including eight procedural ruptures, six thromboembolic events and one case of early hemorrhage. Compared with larger aneurysms, treatment of very small aneurysms was associated...

  13. Intestinal infarction: A complication of endovascular therapy

    International Nuclear Information System (INIS)

    England, Andrew; Butterfield, John S.; Sukumar, Sathi; Thompson, David; Roulson, Jo-An; Pritchard, Susan; Ashleigh, Raymond J.

    2007-01-01

    This report presents a rare case of intestinal infarction following endovascular therapy. A female patient who had undergone an internal carotid artery stenting procedure presented suddenly with abdominal pain. Radiological and clinical examinations at the time suggested a picture of intestinal ischaemia, in view of the patient's general conditions and co-existing morbidities surgical intervention was not considered to be an option. The patient died 4 days after the carotid stenting procedure, post-mortem examination revealed infarction of the ileum and caecum. The learning outcomes are if performing endovascular therapy in a patient with diffuse atherosclerotic disease early consideration of intestinal ischaemia should be given to any patient who presents with acute post-procedural abdominal pain

  14. Endovascular revascularization for aortoiliac atherosclerotic disease

    Directory of Open Access Journals (Sweden)

    Aggarwal V

    2016-03-01

    Full Text Available Vikas Aggarwal,1 Stephen W Waldo,2,3 Ehrin J Armstrong2,3 1Prairie Heart Institute, St John's Hospital, Springfield, IL, 2Section of Cardiology, Denver Veterans Affairs Medical Center, 3Section of Cardiology, University of Colorado, Aurora, CO, USA Abstract: Atherosclerotic iliac artery disease is increasingly being treated with endovascular techniques. A number of new stent technologies can be utilized with high long-term patency, including self-expanding stents, balloon-expandable stents, and covered stents, but comparative data on these stent types and in more complex lesions are lacking. This article provides a review of currently available iliac stent technologies, as well as complex procedural aspects of iliac artery interventions, including approaches to the treatment of iliac bifurcation disease, long segment occlusions, choice of stent type, and treatment of iliac artery in-stent restenosis. Keywords: peripheral artery disease, iliac artery, balloon expandable stent, self expanding stent, covered stent, claudication, endovascular

  15. Intestinal infarction: A complication of endovascular therapy

    Energy Technology Data Exchange (ETDEWEB)

    England, Andrew [Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom)]. E-mail: andrew.england@smtr.nhs.uk; Butterfield, John S. [Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom); Sukumar, Sathi [Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom); Thompson, David [Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom); Roulson, Jo-An [Department of Histopathology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom); Pritchard, Susan [Department of Histopathology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom); Ashleigh, Raymond J. [Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Wythenshawe, Manchester M23 9LT (United Kingdom)

    2007-08-15

    This report presents a rare case of intestinal infarction following endovascular therapy. A female patient who had undergone an internal carotid artery stenting procedure presented suddenly with abdominal pain. Radiological and clinical examinations at the time suggested a picture of intestinal ischaemia, in view of the patient's general conditions and co-existing morbidities surgical intervention was not considered to be an option. The patient died 4 days after the carotid stenting procedure, post-mortem examination revealed infarction of the ileum and caecum. The learning outcomes are if performing endovascular therapy in a patient with diffuse atherosclerotic disease early consideration of intestinal ischaemia should be given to any patient who presents with acute post-procedural abdominal pain.

  16. Endovascular Treatment of Visceral Aneurysms and Pseudoaneurysms: Long-term Outcomes from a Multicenter European Study

    International Nuclear Information System (INIS)

    Spiliopoulos, Stavros; Sabharwal, Tarun; Karnabatidis, Dimitrios; Brountzos, Elias; Katsanos, Konstantinos; Krokidis, Miltiadis; Gkoutzios, Panagiotis; Siablis, Dimitrios; Adam, Andreas

    2012-01-01

    Purpose: To investigate the percutaneous endovascular management of visceral aneurysms (VA) and visceral pseudoaneurysms (VPA) treated in three European interventional radiology departments. Methods: Patient archives from the department’s databases were examined and retrospectively analyzed. Patients diagnosed between 2000 and 2010 with VA and/or VPA, confirmed by computed tomography angiography, magnetic resonance angiography, or digital subtraction angiography and treated exclusively with percutaneous endovascular methods, were included in the study. The study’s primary end points were procedural technical success, target lesion reintervention rate, and periprocedural mortality rate. Secondary end points included major and minor complications rates. Results: The medical records of 54 patients (41 male, mean age 55 ± 18.1 years) with 58 VAs or VPAs and treated with various percutaneous endovascular therapeutic modalities were analyzed. In total, 21 VAs (mean diameter 49.4 ± 21 mm, range 20–100 mm) and 37 VPAs (mean diameter 25.1 ± 14.6 mm, range 8–60 mm) were treated. Procedural technical success was achieved in 100% of the cases, while target lesion reintervention rate was 6.1% (2 of 33) and 14.2% (3 of 21) in the VPA and VA groups, respectively. Mean clinical follow-up period was 19.1 ± 21.4 months. Overall periprocedural mortality rate was 3% (1 of 33) in the VPA group and 0% (0 of 21) in the VA group. Conclusion: Percutaneous endovascular treatment of VAs and VPAs is safe and effective with low morbidity and mortality. There is a small but significant reintervention rate, particularly for true aneurysms; dedicated follow-up imaging is recommended. Successful aneurysm exclusion was achieved in all cases with a second procedure.

  17. Evaluation of the efficacy and safety of endovascular management for transplant renal artery stenosis

    Directory of Open Access Journals (Sweden)

    Leonardo G.M. Valle

    Full Text Available OBJECTIVES: To evaluate the safety and efficacy of endovascular intervention with angioplasty and stent placement in patients with transplant renal artery stenosis. METHODS: All patients diagnosed with transplant renal artery stenosis and graft dysfunction or resistant systemic hypertension who underwent endovascular treatment with stenting from February 2011 to April 2016 were included in this study. The primary endpoint was clinical success, and the secondary endpoints were technical success, complication rate and stent patency. RESULTS: Twenty-four patients with transplant renal artery stenosis underwent endovascular treatment, and three of them required reinterventions, resulting in a total of 27 procedures. The clinical success rate was 100%. All graft dysfunction patients showed decreased serum creatinine levels and improved estimated glomerular filtration rates and creatinine levels. Patients with high blood pressure also showed improved control of systemic blood pressure and decreased use of antihypertensive drugs. The technical success rate of the procedure was 97%. Primary patency and assisted primary patency rates at one year were 90.5% and 100%, respectively. The mean follow-up time of patients was 794.04 days after angioplasty. CONCLUSION: Angioplasty with stent placement for the treatment of transplant renal artery stenosis is a safe and effective technique with good results in both the short and long term.

  18. Endovascular Exclusion of Renal Artery Aneurysm

    International Nuclear Information System (INIS)

    Andersen, Poul Erik; Rohr, Nils

    2005-01-01

    A patient who was operated for an abdominal aortic aneurysm 7 years earlier presented with recently discovered iliac and renal artery aneurysms. The renal artery had an angulation of 90 o , but the aneurysm was successfully excluded using a covered vascular stent graft placed over an extrastiff guidewire. Even in cases of complex anatomy of a renal aneurysm, endovascular treatment should be considered. With development of more flexible and low-profile endoprosthesis with accurate deployment, these have become more usable

  19. Morbidity rate of nervous system among medical personnel occupationally exposed to chronic low dose irradiation

    International Nuclear Information System (INIS)

    Jonkova, A.

    1987-01-01

    The morbidity rate of the nervous system among 1190 subjects, medical personnel, working with sources and environment of ionizing radiation was studied by the personal analysis of the diseases, written down in the personal out-patient department cards as well as of a control group of 870 medical workers of various other specialities. The morbidity rate of the nervous system among the medical personnel, exposed to chronic occupational radiation effect, was established not to be higher than that of the other medical workers - 38.0 and 40.3% respectively. Neuroses and peripheral nervous diseases have the greatest relative share in the structure of morbidity rate of the nervous system in both groups examined, with no statistical significance in the differences of the indices. The significantly higher incidence of autonome dystonias, established among the personnel from the X-ray departments and consulting rooms could be discussed in connection with the great relative share of the subjects from that group with a length of service over 15 years and had received the possible maximum cumulative equivalent doses. 3 tabs., 21 refs

  20. Functional outcome after primary endovascular therapy or IV thrombolysis alone for stroke. An observational, comparative effectiveness study.

    Science.gov (United States)

    Abilleira, Sònia; Ribera, Aida; Dávalos, Antonio; Ribó, Marc; Chamorro, Angel; Cardona, Pere; Molina, Carlos A; Martínez-Yélamos, Antonio; Urra, Xabier; Dorado, Laura; Roquer, Jaume; Martí-Fàbregas, Joan; Aja, Lucía; Tomasello, Alejandro; Castaño, Carlos; Blasco, Jordi; Cánovas, David; Castellanos, Mar; Krupinski, Jerzy; Guimaraens, Leopoldo; Perendreu, Joan; Ustrell, Xavier; Purroy, Francisco; Gómez-Choco, Manuel; Baiges, Joan Josep; Cocho, Dolores; Saura, Júlia; Gallofré, Miquel

    2014-01-01

    Among the acute ischemic stroke patients with large vessel occlusions and contraindications for the use of IV thrombolysis, mainly on oral anticoagulation or presenting too late, primary endovascular therapy is often performed as an alternative to the standard therapy even though evidence supporting the use of endovascular reperfusion therapies is not yet established. Using different statistical approaches, we compared the functional independence rates at 3 months among patients undergoing primary endovascular therapy and patients treated only with IV thrombolysis. We used data from a prospective, government-mandated and externally audited registry of reperfusion therapies for ischemic stroke (January 2011 to November 2012). Patients were selected if treated with either IV thrombolysis alone (n = 1,582) or primary endovascular thrombectomy (n = 250). A series of exclusions were made to homogenize the clinical characteristics among the two groups. We then carried out multivariate logistic regression and propensity score matching analyses on the final study sample (n = 1,179) to compare functional independence at 3 months, as measured by the modified Rankin scale scores 0-2, between the two groups. The unadjusted likelihood of good outcome was poorer among the endovascular group (OR: 0.69; 95% CI: 0.47-1.0). After adjustment, no differences by treatment modality were seen (OR: 1.51; 95% CI: 0.93-2.43 for primary endovascular therapy). Patients undergoing endovascular thrombectomy within 180-270 min (OR: 2.89; 95% CI: 1.17-7.15) and patients with severe strokes (OR: 1.84; 95% CI: 1.02-3.35) did better than their intravenous thrombolysis counterparts. The propensity score-matched analyses with and without adjustment by additional covariates showed that endovascular thrombectomy was as effective as intravenous thrombolysis alone in achieving functional independence (OR for unadjusted propensity score matched: 1.35; 95% CI: 0.9-2.02, OR for adjusted propensity score

  1. Current status of endovascular catheter robotics.

    Science.gov (United States)

    Lumsden, Alan B; Bismuth, Jean

    2018-06-01

    In this review, we will detail the evolution of endovascular therapy as the basis for the development of catheter-based robotics. In parallel, we will outline the evolution of robotics in the surgical space and how the convergence of technology and the entrepreneurs who push this evolution have led to the development of endovascular robots. The current state-of-the-art and future directions and potential are summarized for the reader. Information in this review has been drawn primarily from our personal clinical and preclinical experience in use of catheter robotics, coupled with some ground-breaking work reported from a few other major centers who have embraced the technology's capabilities and opportunities. Several case studies demonstrating the unique capabilities of a precisely controlled catheter are presented. Most of the preclinical work was performed in the advanced imaging and navigation laboratory. In this unique facility, the interface of advanced imaging techniques and robotic guidance is being explored. Although this procedure employs a very high-tech approach to navigation inside the endovascular space, we have conveyed the kind of opportunities that this technology affords to integrate 3D imaging and 3D control. Further, we present the opportunity of semi-autonomous motion of these devices to a target. For the interventionist, enhanced precision can be achieved in a nearly radiation-free environment.

  2. Endovascular treatment of intracranial venous sinus thrombosis

    International Nuclear Information System (INIS)

    Xu Shubin; Liang Zhihui; Cui Jinguo; Tian Huiqin; Li Liang; Chen Feng

    2009-01-01

    Objective: To evaluate the clinical efficacy and safety of endovascular treatment for intracranial venous sinus thrombosis. Methods: Ten patients with intracranial venous sinus thrombosis, confirmed by CT, MRI, MRV and / or DSA and encountered during the period of Aug. 2005-Aug. 2007, were treated with endovascular management after they failed to respond to anticoagulant therapy. Of ten patients, intravenous thrombolysis and mechanical thrombus maceration were carried out in 6, while intravenous thrombolysis, mechanical thrombus maceration together with intra-arterial thrombolysis were employed in 4. After the treatment, the anticoagulant therapy continued for 6 months. The patients were followed up for 12-29 months (mean 21 months). Results: After the treatment, the clinical symptoms and signs were completely or partially relieved in eight patients, including disappearance of headache (n=6) and relive of headache (n=2). No obvious improvement was found in one patient and linguistic function disturbance was seen in the remaining one. Lumbar puncture showed that the cerebrospinal fluid pressure returned to normal in all patients. Neither recurrence of thrombosis nor new symptom of neuralgic dysfunction was observed. No procedure-related intracranial or systemic hemorrhagic complications occurred both during and after the operation. Conclusion: Endovascular treatment is an effective and safe procedure for the potentially catastrophic intracranial venous thrombosis. (authors)

  3. Late graft explants in endovascular aneurysm repair.

    Science.gov (United States)

    Turney, Eric J; Steenberge, Sean P; Lyden, Sean P; Eagleton, Matthew J; Srivastava, Sunita D; Sarac, Timur P; Kelso, Rebecca L; Clair, Daniel G

    2014-04-01

    With more than a decade of use of endovascular aneurysm repair (EVAR), we expect to see a rise in the number of failing endografts. We review a single-center experience with EVAR explants to identify patterns of presentation and understand operative outcomes that may alter clinical management. A retrospective analysis of EVARs requiring late explants, >1 month after implant, was performed. Patient demographics, type of graft, duration of implant, reason for removal, operative technique, length of stay, complications, and in-hospital and late mortality were reviewed. During 1999 to 2012, 100 patients (91% men) required EVAR explant, of which 61 were placed at another institution. The average age was 75 years (range, 50-93 years). The median length of time since implantation was 41 months (range, 1-144 months). Explanted grafts included 25 AneuRx (Medtronic, Minneapolis, Minn), 25 Excluder (W. L. Gore & Associates, Flagstaff, Ariz), 17 Zenith (Cook Medical, Bloomington, Ind), 15 Talent (Medtronic), 10 Ancure (Guidant, Indianapolis, Ind), 4 Powerlink (Endologix, Irvine, Calif), 1 Endurant (Medtronic), 1 Quantum LP (Cordis, Miami Lakes, Fla), 1 Aorta Uni Iliac Rupture Graft (Cook Medical, Bloomington, Ind), and 1 homemade tube graft. Overall 30-day mortality was 17%, with an elective case mortality of 9.9%, nonelective case mortality of 37%, and 56% mortality for ruptures. Endoleak was the most common indication for explant, with one or more endoleaks present in 82% (type I, 40%; II, 30%; III, 22%; endotension, 6%; multiple, 16%). Other reasons for explant included infection (13%), acute thrombosis (4%), and claudication (1%). In the first 12 months, 23 patients required explants, with type I endoleak (48%) and infection (35%) the most frequent indication. Conversely, 22 patients required explants after 5 years, with type I (36%) and type III (32%) endoleak responsible for most indications. The rate of EVAR late explants has increased during the past decade at our

  4. Study of the performance of ATLAS muon drift-tube chambers in magntic fields and at high irradiation rates

    Energy Technology Data Exchange (ETDEWEB)

    Valderanis, Chrysostomos

    2012-07-26

    The performance of ATLAS muon drift-tube (MDT) chambers has been studied in detail using high-energy muon beams. The measurements of the drift tube properties in magnetic fields showed that inelastic collisions of the drifting electrons with the CO{sub 2} molecules in the Ar:CO{sub 2} (93:7) gas mixture of the MDT chambers have to be taken into account in the simulation of the drift properties. Such inelastic collisions are now correctly treated by the Garfield simulation programme from version 9 providing an accurate description of the behaviour of the ATLAS muon drift tubes, in particular in the magnetic field. Measurements at the Gamma Irradiation Facility at CERN were performed to study the performance of the MDT chambers in the presence of high {gamma} ray background fluences. The chambers have a spatial resolution better than 40 {mu}m at the nominal background rates expected at the Large Hadron Collider design luminosity of 10{sup 34} cm{sup -2}s{sup -1} and a resolution better than 50 {mu}m for up to five times higher background rates. Efficient muon detection up to background counting rates of 500 kHz per tube corresponding to 35% occupancy was demonstrated.

  5. Total body irradiation (TBI) in pediatric patients. A single-center experience after 30 years of low-dose rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmeier, Claudia; Thoennessen, Daniel; Negretti, Laura; Streller, Tino; Luetolf, Urs Martin [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Bourquin, Jean-Pierre [University Children' s Hospital Zurich (Switzerland). Dept. of Hemato-Oncology; Oertel, Susanne [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Heidelberg Univ. (Germany). Dept. of Radiation Oncology

    2010-11-15

    To retrospectively analyze patient characteristics, treatment, and treatment outcome of pediatric patients with hematologic diseases treated with total body irradiation (TBI) between 1978 and 2006. 32 pediatric patients were referred to the Department of Radiation-Oncology at the University of Zurich for TBI. Records of regular follow-up of 28 patients were available for review. Patient characteristics as well as treatment outcome regarding local control and overall survival were assessed. A total of 18 patients suffered from acute lymphoblastic leukemia (ALL), 5 from acute and 2 from chronic myelogenous leukemia, 1 from non-Hodgkin lymphoma, and 2 from anaplastic anemia. The cohort consisted of 15 patients referred after first remission and 13 patients with relapsed leukemia. Mean follow-up was 34 months (2-196 months) with 15 patients alive at the time of last follow-up. Eight patients died of recurrent disease, 1 of graft vs. host reaction, 2 of sepsis, and 2 patients died of a secondary malignancy. The 5-year overall survival rate (OS) was 60%. Overall survival was significantly inferior in patients treated after relapse compared to those treated for newly diagnosed leukemia (24% versus 74%; p=0.004). At the time of last follow-up, 11 patients survived for more than 36 months following TBI. Late effects (RTOG {>=}3) were pneumonitis in 1 patient, chronic bronchitis in 1 patient, cardiomyopathy in 2 patients, severe cataractogenesis in 1 patient (48 months after TBI with 10 Gy in a single dose) and secondary malignancies in 2 patients (36 and 190 months after TBI). Growth disturbances were observed in all patients treated prepubertally. In 2 patients with identical twins treated at ages 2 and 7, a loss of 8% in final height of the treated twin was observed. As severe late sequelae after TBI, we observed 2 secondary malignancies in 11 patients who survived in excess of 36 months. However, long-term morbidity is moderate following treatment with the fractionated

  6. Temporal dependence of the mass ablation rate in uv irradiated spherical targets

    International Nuclear Information System (INIS)

    Delettrez, J.; Jaanimagi, P.A.; Henke, B.L.; Richardson, M.C.

    1985-01-01

    In this talk, measurements of thermal transport in spherical geometry using time-resolved x-ray spectroscopy are presented. The time dependence of the mass ablation rate (m) is determined by following the progress of the ablation surface through thin layers of material embedded at various depths below the surface of the target. These measurements made with 6, 12 and 24 uv (351 nm) beams from OMEGA are compared to previous thermal transport data and are in qualitative agreement with detailed LILAC hydrodynamic code simulations which predict a sharp decrease in m after the peak of the laser pulse. Viewgraphs of the talk comprise the report

  7. Strategy of endovascular versus open repair for patients with clinical diagnosis of ruptured abdominal aortic aneurysm: the IMPROVE RCT.

    Science.gov (United States)

    Ulug, Pinar; Hinchliffe, Robert J; Sweeting, Michael J; Gomes, Manuel; Thompson, Matthew T; Thompson, Simon G; Grieve, Richard J; Ashleigh, Raymond; Greenhalgh, Roger M; Powell, Janet T

    2018-05-01

    in whom repair was started for a proven rupture (OR 0.62, 95% CI 0.43 to 0.89; p  = 0.009), whereas aneurysm-related reintervention rates were non-significantly higher in this group. At 3 years, considering all participants, there was a mean difference of 0.174 quality-adjusted life-years (QALYs) (95% CI 0.002 to 0.353 QALYs) and, among the endovascular strategy group, a cost difference of -£2605 (95% CI -£5966 to £702), leading to 88% of estimates in the cost-effectiveness plane being in the quadrant showing the endovascular strategy to be 'dominant'. Because of the pragmatic design of this trial, 33 participants in the endovascular strategy group and 26 in the open repair group breached randomisation allocation. The endovascular strategy was not associated with a significant reduction in either 30-day mortality or cost but was associated with faster participant recovery. By 3 years, the endovascular strategy showed a survival and QALY gain and was highly likely to be cost-effective. Future research could include improving resuscitation for older persons with circulatory collapse, the impact of local anaesthesia and emergency consent procedures. Current Controlled Trials ISRCTN48334791 and NCT00746122. This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment ; Vol. 22, No. 31. See the NIHR Journals Library website for further project information.

  8. Celiac Injury Due to Arcuate Ligament: An Endovascular Approach

    Energy Technology Data Exchange (ETDEWEB)

    Zini, Chiara, E-mail: zini.chiara@gmail.com; Corona, Mario, E-mail: mario.corona@uniroma.it; Boatta, Emanuele, E-mail: emanuele.boatta@yahoo.it; Wlderk, Andrea, E-mail: a.wlderk@virgilio.it; Salvatori, Filippo Maria, E-mail: filippomaria.salvatori@uniroma1.it; Fanelli, Fabrizio, E-mail: fabrizio.fanelli@uniroma1.it [' Sapienza,' -University of Rome, Vascular and Interventional Radiology Unit, Radiology, Oncology and Pathology Department (Italy)

    2013-06-15

    Celiac trunk injures are rare events, with high mortality rates and difficult management. Endovascular treatment may be considered to avoid bleeding. We report a case of severe bleeding in a 37-year-old man resulting from celiac trunk stretching after a motorcycle crash. Because direct celiac trunk catheterization was not possible, a retrograde catheterization of the common hepatic artery was performed via the superior mesenteric artery. Two vascular plugs (type IV) were released, and the exclusion of the celiac trunk origin was completed with the deployment of an aortic cuff. The patient's clinical condition immediately improved, and after 6 months' follow-up, imaging confirmed the complete exclusion of the celiac trunk.

  9. Celiac Injury Due to Arcuate Ligament: An Endovascular Approach

    International Nuclear Information System (INIS)

    Zini, Chiara; Corona, Mario; Boatta, Emanuele; Wlderk, Andrea; Salvatori, Filippo Maria; Fanelli, Fabrizio

    2013-01-01

    Celiac trunk injures are rare events, with high mortality rates and difficult management. Endovascular treatment may be considered to avoid bleeding. We report a case of severe bleeding in a 37-year-old man resulting from celiac trunk stretching after a motorcycle crash. Because direct celiac trunk catheterization was not possible, a retrograde catheterization of the common hepatic artery was performed via the superior mesenteric artery. Two vascular plugs (type IV) were released, and the exclusion of the celiac trunk origin was completed with the deployment of an aortic cuff. The patient’s clinical condition immediately improved, and after 6 months’ follow-up, imaging confirmed the complete exclusion of the celiac trunk.

  10. Comparison of thermoradiosensitization in two human melanoma cell lines and one fibroblast cell line by concurrent mild hyperthermia and low-dose-rate irradiation

    International Nuclear Information System (INIS)

    Raaphorst, G.P.; Bussey, A.; Heller, D.P.; Ng, C.E.

    1994-01-01

    Two human melanoma cell lines, one radioresistant (Sk-MEL-3) and one radiosensitive (HT-144), and a normal human fibroblast line (AG1522) were evaluated for thermoradiosensitization of low-dose-rate irradiation by concurrent mild hyperthermia (39-41 degrees C). None of the cell lines expressed chronic thermotolerance during heating at 39-41 degrees C. The SK-MEL-3 cells were the most heat sensitive, while AG1522 and HT-144 cells had the same sensitivity at 39 and 40 degrees C but HT-144 cells were more sensitive at 41 degrees C. All cell lines expressed thermal enhancement of radiosensitivity with heating during irradiation which increased with heating temperature. The SK-MEL-3 cells, which were the most resistant to radiation and demonstrated the greatest repair of sublethal damage (SLD) during low-dose-rate irradiation, had the greatest thermal enhancement of radiosensitivity, while the HT144 cells, which were the most sensitive and expressed little repair of SLD during low-dose-rate irradiation, had the smallest thermal enhancement of radiosensitivity. These data show that concurrent mild hyperthermia during low-dose-rate irradiation may be most efficacious in radiation-resistant tumor cells which express resistance through an enhanced capacity for repair of SLD. 24 refs., 5 figs., 1 tab

  11. Accelerated partial-breast irradiation using high-dose-rate interstitial brachytherapy: 12-year update of a prospective clinical study

    International Nuclear Information System (INIS)

    Polgar, Csaba; Major, Tibor; Fodor, Janos; Sulyok, Zoltan; Somogyi, Andras; Loevey, Katalin; Nemeth, Gyoergy; Kasler, Miklos

    2010-01-01

    Background and purpose: To report the 12-year updated results of accelerated partial-breast irradiation (APBI) using multicatheter interstitial high-dose-rate (HDR) brachytherapy (BT). Patients and methods: Forty-five prospectively selected patients with T1N0-N1mi, nonlobular breast cancer without the presence of an extensive intraductal component and with negative surgical margins were treated with APBI after breast-conserving surgery (BCS) using interstitial HDR BT. A total dose of 30.3 Gy (n = 8) and 36.4 Gy (n = 37) in seven fractions within 4 days was delivered to the tumour bed plus a 1-2 cm margin. The median follow-up time was 133 months for surviving patients. Local and regional control, disease-free (DFS), cancer-specific (CSS), and overall survival (OS), as well as late side effects, and cosmetic results were assessed. Results: Four (8.9%) ipsilateral breast tumour recurrences were observed, for a 5-, 10-, and 12-year actuarial rate of 4.4%, 9.3%, and 9.3%, respectively. A total of two regional nodal failures were observed for a 12-year actuarial rate of 4.4%. The 12-year DFS, CSS, and OS was 75.3%, 91.1%, and 88.9%, respectively. Grade 3 fibrosis was observed in one patient (2.2%). No patient developed grade 3 teleangiectasia. Fat necrosis requiring surgical intervention occurred in one woman (2.2%). Cosmetic results were rated excellent or good in 35 patients (77.8%). Conclusions: Twelve-year results with APBI using HDR multicatheter interstitial implants continue to demonstrate excellent long-term local tumour control, survival, and cosmetic results with a low-rate of late side effects.

  12. Endovascular Therapeutic Approaches for Acute Superior Mesenteric Artery Occlusion

    International Nuclear Information System (INIS)

    Acosta, S.; Sonesson, B.; Resch, T.

    2009-01-01

    The purpose of this study was to characterize the outcome of attempted endovascular intervention in patients with acute embolic or thrombotic superior mesenteric artery (SMA) occlusion. The records of 21 patients during a 3-year period between 2005 and 2008 were retrieved from the in-hospital registry. The first group included 10 patients (6 women and 4 men; median age 78 years) with acute embolic occlusion of the SMA. The median duration of symptoms from symptom onset to angiography was 30 hours (range 6 to 120). Synchronous emboli (n = 12) occurred in 6 patients. Embolus aspiration was performed in 9 patients, and 7 of these had satisfactory results. Complementary local thrombolysis was successful in 2 of 3 patients. Residual emboli were present at completion angiography in all 7 patients who underwent successful aspiration embolectomy, and bowel resection was necessary in only 1 of these patients. One serious complication occurred because of a long SMA dissection. The in-hospital survival rate was 90% (9 of 10 patients). The second group included 11 patients (10 women and 1 man; median age 68 years) with atherosclerotic acute SMA occlusions. The median time of symptom duration before intervention was 97 hours (range 17 to 384). The brachial, femoral, and SMA routes were used in 6, 7, and 5 patients, respectively. SMA stenting was performed through an antegrade (n = 7) or retrograde (n = 3) approach. Bowel resection was necessary in 4 patients. No major complications occurred. The in-hospital survival rate was 82% (9 of 11 patients). Endovascular therapy of acute SMA occlusion provides a good alternative to open surgery.

  13. Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

    Science.gov (United States)

    Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

    2009-01-01

    condensation (PCC) technique at the first mitosis post-irradiation. Chromosomes were analyzed using a multicolor fluorescence in-situ hybridization (mFISH) chromosome painting method. Preliminary analysis showed that chromosomal exchanges were increased in the cells treated with the specific ATM inhibitor. Possible cytogenetic signatures of acute and low dose-rate gamma irradiation in ATM or Nibrin deficient and suppressed cells will be discussed.

  14. Model of the contribution of the compton generated radiation to the dose rate for an experiment in a semi industrial irradiation plant

    International Nuclear Information System (INIS)

    Mangussi, Josefina

    2007-01-01

    The model of the build up contribution to the absorbed dose rate in a semi industrial irradiation plant is presented. A static irradiation of a lucite phantom with and without water is modeled. The absorbed dose was measured with silver and potassium dichromate dosemeters. Two approximations are used, the first one is a global adjustment of the attenuation coefficient and the second one consists in a detailed description of the Compton scattering. A specific numerical model is developed for each approximation and the absorbed dose rates calculated are compared with the experimental measurements. The achievements and limitations of both models are discussed. (author) [es

  15. Does hyperbaric oxygen treatment have the potential to increase salivary flow rate and reduce xerostomia in previously irradiated head and neck cancer patients? A pilot study

    DEFF Research Database (Denmark)

    Forner, Lone; Hansen, Ole Hyldegaard; von Brockdorff, Annet Schack

    2011-01-01

    in irradiated head and neck cancer patients. Eighty patients eligible for HBO treatment on the indication of prevention/treatment of osteoradionecrosis or soft tissue radiation injury were consecutively sampled, of whom 45 had hyposalivation (i.e. unstimulated whole saliva (UWS) flow rate......Irradiated head and neck cancer survivors treated in the Hyperbaric Oxygen (HBO) Unit, Copenhagen University Hospital, spontaneously reported improvement of radiation-induced dry mouth feeling. The aim of this pilot study was to evaluate salivary flow rate and xerostomia before and after HBO...

  16. Endovascular treatment of cerebral aneurysms - a cost analysis | Le ...

    African Journals Online (AJOL)

    The average cost for endovascular treatment per patient was R37 041. Surgical treatment was more expensive at R44 104, a difference of 16%. Conclusions. Despite the high cost of endovascular devices, appropriate use of this technology ultimately offers less expensive treatment than microsurgical clipping of aneurysms.

  17. High dose-rate irradiation of materials with pulsed ion beams at NDCX-II

    Science.gov (United States)

    Seidl, Peter; Treffert, F.; Ji, Q.; Ludewigt, B.; Persaud, A.; Kong, X.; de Leon, S. J.; Dowling, E.; Waldron, W. L.; Schenkel, T.; Barnard, J. J.; Friedman, A.; Grote, D. P.; Stepanov, A.; Gilson, E. P.; Kaganovich, I. D.

    2017-10-01

    Charged particle radiation effects in materials is important for the design of fusion plasma facing components. Also, radiation effects in semiconductor devices are of interest for many applications such as detectors and space electronics. We present results from radiation effects studies with intense pulses of helium ions that impinged on thin samples at the induction linac at Berkeley Lab (Neutralized Drift Compression Experiment-II). Intense bunches of 1.2 MeV He+ ions with peak currents of 2 A, 1-mm beam spot radius and 2-30 ns FWHM duration create controlled high instantaneous dose rates enabling the exploration of collective damage effects. We use in-situ diagnostics to monitor transient effects due to rapid heating and the ionization and damage cascade dynamics. For tin, single pulses deposit sufficient energy in the foil to drive phase transitions. A new Thomson parabola to measures ion energy loss and charge state distributions following transmission of a few micron thick samples. In silicon, ion pulses induce free electron densities of order 1021 cm-3. Supported by the Office of Science of the US DOE under contracts DE-AC0205CH11231, DE-AC52-07NA27344 and DE-AC02-09CH11466 and by the China Scholarship Council.

  18. NPK, protein content and yield of broccoli as affected by gamma rays seeds irradiation and phosphorus fertilizer rates

    Energy Technology Data Exchange (ETDEWEB)

    El-Desoki, S A [Botany Department, Faculty of Agriculture, Moshtohor, Zagazig University (Egypt); Abdallah, A A.G.; Awad, S M; Aboel-Kheir, O H [Plant Research Department, Nuclear Research Center, Cairo (Egypt)

    2005-07-01

    Two field experiments were carried out during 1999/2000 and 2000/2001 winter growing seasons at the experimental farm of Nuclear Research Center, Atomic Energy Authority, Inshas, Egypt. The experiments were conducted to study the effect of pre sowing-seeds irradiation with different doses of gamma rays (0, 2, 3 and 4 Gy) and different phosphorus fertilizer application rates, 0, 30, 60 and 90 k P{sub 2}O{sub 5} /fed) on NPK content of leaves and spear, and protein content in spears at maturity, spear diameter, main spear fresh and dry weight per plant, total spear fresh weight per plant and total spear yield. In general, exposing broccoli seeds to different gamma ray doses up to 4 Gy prior to sowing increased the above mentioned parameters with different magnitudes comparing with the non-irradiated control plants. The highest percentage of increase was obtained by exposing broccoli seeds to 3 Gy. There were non-significant differences between 3 and 4 Gy treatments during the two growing seasons. With respect to the effect of phosphorus fertilizer application rates on the studied parameters, increasing phosphorus application rates up to 90 kg P{sub 2}O{sub 5}/fed increased the above mentioned parameters. The highest percentage of increase was obtained by applying 90 kg P{sub 2}O{sub 5}/fed. The interaction, gamma ray and P level showed phosphorus there were significant differences in main spear fresh and dry weight per plant, total spear yield and spear diameter in first season. The highest value was obtained by 3 Gy and 90 kg P{sub 2}O{sub 5}/fed. Also there were significant effects on NPK content in broccoli leaves at 90 days after transplanting (DAT) except P in second season and nonsignificant values of broccoli spear at harvest except N, K in first season. The highest protein content of broccoli spears at harvest was obtained with 2 Gy and 30 kg P{sub 25}/fed.

  19. The rate of DNA synthesis in normal human and ataxia telangiectasia cells after exposure to X-irradiation

    International Nuclear Information System (INIS)

    Wit, J. de; Bootsma, D.; Jaspers, N.G.J.; Rijksverdedigingsorganisatie TNO, Rijswijk

    1981-01-01

    The rate of DNA synthesis was studied in normal cell strains and in strains from patients suffering from the inherited disorder ataxia telangiectasia (AT). After exposure to relatively low doses of oxic X-rays (0- 4 krad) DNA synthesis was depressed in AT cell strains to a significantly lesser extent than in normal cells. This response was observed in both an excision-deficient and an excision-proficient strain. In contrast, there was no difference in DNA-synthesis inhibition between AT and normal cells after UV exposure. After X-irradiation of cells from patients with xeroderma pigmentosum, both complementation group A and XP variants, the observed rate of DNA synthesis was equal to that in normal cells. An exception was the strain XP3BR which has been shown to be X-ray-sensitive. This strain exhibited diminished DNA synthesis inhibition after X-ray doses below 1 krad. These data suggest a relationship between hypersensitivity to X-rays and diminished depression of DNA synthesis. (orig.)

  20. Dose rate and total dose dependence of the 1/f noise performance of a GaAs operational amplifier during irradiation

    International Nuclear Information System (INIS)

    Hiemstra, D.M.

    1995-01-01

    A pictorial of a sectioned view of the torus of the International Thermonuclear Experimental Reactor (ITER) is shown. Maintenance and inspection of the reactor are required to be performed remotely. This is due to the high gamma radiation environment in vessel during inspection and maintenance activities. The custom GaAs operational amplifier is to be used to readout sensors on the in-vessel manipulator and inspection equipment. The gamma dose rate during maintenance and inspection is anticipated to be 3 Mrad(GaAs)/hour. Here, dose rate and total dose dependence of the 1/f noise performance of a custom GaAs MESFET operational amplifier during irradiation are presented. Dose rate dependent 1/f noise degradation during irradiation is believed to be due to electron trapping in deep levels, enhanced by backgating and shallow traps excited during irradiation. The reduction of this affect with accumulated total dose is believed to be due a reduction of deep level site concentration associated with substitutional oxygen. Post irradiation 1/f noise degradation is also presented.The generation-recombination noise observed post irradiation can be attributed to the production of shallow traps due to ionizing radiation

  1. Evaluation of the effect of radiation levels and dose rates in irradiation of murine fibroblasts used as a feeder layer in the culture of human keratinocytes

    International Nuclear Information System (INIS)

    Yoshito, Daniele; Almeida, Tiago L.; Santin, Stefany Plumeri; Somessari, Elizabeth S.R.; Silveira, Carlos G. da; Mathor, Monica B.; Altran, Silvana C.; Isaac, Cesar

    2009-01-01

    In 1975, Rheinwald and Green published an effective methodology for obtaining and cultivating human keratinocytes. This methodology consisted of seeding keratinocytes onto a feeder layer composed of lineage 3T3 murine fibroblasts, the proliferation rate of which is then controlled through the action of ionizing radiation. The presence of the feeder layer encourages the development of keratinocyte colonies and their propagation in similar cultures, becoming possible several clinical applications as skin substitutes or wound dressings in situations such as post burn extensive skin loss and other skin disorders. However, good development of these keratinocytes depends on a high quality feeder layer among other factors. In the present work, we evaluated the relationship between radiation levels and dose rates applied to fibroblasts used in construction of feeder layers and the radiation effect on keratinocytes colonies forming efficiency. Results indicate 3T3 lineage murine fibroblasts irradiated with doses varying between 60 and 100 Gy can be used as a feeder layer immediately after irradiation or storage of the irradiated cells in suspension at 4 g C for 24 hours with similar results. The exception is when the irradiation dose rate is 2.75 Gyh -1 ; in this case, results suggested that the fibroblasts should be used immediately after irradiation. (author)

  2. Distal posterior cerebral artery aneurysms: Retrospective review of characteristics and endovascular treatment

    International Nuclear Information System (INIS)

    Baek, Jin Wook; Jeong, Bae Woong; Seung, Won Bae

    2016-01-01

    The objective of this study was to review the clinical outcome after treatment of distal posterior cerebral artery (PCA) aneurysms via endovascular approach. Eleven patients with 11 distal PCA aneurysms who were treated via endovascular approach in Inje University Busan Paik Hospital and Kosin University Gospel Hospital from December 2002 to December 2013 were retrospectively reviewed. Among the 11 patients, there were 3 males (27.3%) and 8 females (72.7%). The mean age was 56.6 years (range 44 -72 years) and the mean aneurysm size was 8.45 mm (3 - 30 mm). Four (36.4%) aneurysms were located in the P2 segment, 6 (54.5%) in the P3 segment and 1 (9.1%) in the P1/2 junction. Seven (63.6%) aneurysms were treated with preservation of the parent artery; and the remaining 4 (36.4%) aneurysms were treated with parent artery occlusion. After treatment, the overall complication rate was 27% with the morbidity rate of 9.1% and the mortality rate of 18%. Endovascular treatment of distal PCA aneurysm might be used to minimize neurologic deficit, considering the diverse and rich collaterals of posterior cerebral artery

  3. Distal posterior cerebral artery aneurysms: Retrospective review of characteristics and endovascular treatment

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Jin Wook [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Jeong, Bae Woong [Dept. of Diagnostic Radiology, Inje University College of Medicine, Busan Paik Hospital, Busan (Korea, Republic of); Seung, Won Bae [Dept. of Neurosurgery, Kosin University College of Medicine, Gospel Hospital, Busan (Korea, Republic of)

    2016-04-15

    The objective of this study was to review the clinical outcome after treatment of distal posterior cerebral artery (PCA) aneurysms via endovascular approach. Eleven patients with 11 distal PCA aneurysms who were treated via endovascular approach in Inje University Busan Paik Hospital and Kosin University Gospel Hospital from December 2002 to December 2013 were retrospectively reviewed. Among the 11 patients, there were 3 males (27.3%) and 8 females (72.7%). The mean age was 56.6 years (range 44 -72 years) and the mean aneurysm size was 8.45 mm (3 - 30 mm). Four (36.4%) aneurysms were located in the P2 segment, 6 (54.5%) in the P3 segment and 1 (9.1%) in the P1/2 junction. Seven (63.6%) aneurysms were treated with preservation of the parent artery; and the remaining 4 (36.4%) aneurysms were treated with parent artery occlusion. After treatment, the overall complication rate was 27% with the morbidity rate of 9.1% and the mortality rate of 18%. Endovascular treatment of distal PCA aneurysm might be used to minimize neurologic deficit, considering the diverse and rich collaterals of posterior cerebral artery.

  4. Simulation and augmented reality in endovascular neurosurgery: lessons from aviation.

    Science.gov (United States)

    Mitha, Alim P; Almekhlafi, Mohammed A; Janjua, Major Jameel J; Albuquerque, Felipe C; McDougall, Cameron G

    2013-01-01

    Endovascular neurosurgery is a discipline strongly dependent on imaging. Therefore, technology that improves how much useful information we can garner from a single image has the potential to dramatically assist decision making during endovascular procedures. Furthermore, education in an image-enhanced environment, especially with the incorporation of simulation, can improve the safety of the procedures and give interventionalists and trainees the opportunity to study or perform simulated procedures before the intervention, much like what is practiced in the field of aviation. Here, we examine the use of simulators in the training of fighter pilots and discuss how similar benefits can compensate for current deficiencies in endovascular training. We describe the types of simulation used for endovascular procedures, including virtual reality, and discuss the relevant data on its utility in training. Finally, the benefit of augmented reality during endovascular procedures is discussed, along with future computerized image enhancement techniques.

  5. Modeling of endovascular patch welding using the computer program LATIS

    International Nuclear Information System (INIS)

    Glinsky, M.E.; London, R.A.; Zimmerman, G.B.; Jacques, S.L.

    1995-01-01

    A new computer program, LATIS, being developed at Lawrence Livermore National Laboratory is used to study the effect of pulsed laser irradiation on endovascular patch welding. Various physical and biophysical effects are included in these simulations: laser light scattering and absorption, tissue heating and heat conduction, vascular cooling, and tissue thermal damage. The geometry of a patch being held against the inner vessel wall (500 μm inner diameter) by a balloon is considered. The system is exposed to light pulsed from an optical fiber inside the balloon. A minimum in the depth of damage into the vessel wall is found. The minimum damage zone is about the thickness of the patch material that is heated by the laser. The more ordered the tissue the thinner the minimum zone of damage. The pulse length which minimizes the zone of damage is found to be the time for energy to diffuse across the layer. The delay time between the pulses is determined by the time for the heated layer to cool down. An optimal pulse length exists which minimizes the total time needed to weld the patch to the wall while keeping the thickness of the damaged tissue to less than 100 μm. For the case that is considered, a patch dyed with light absorbing ICG on the side next to the vessel (thickness of the dyed layer is 60 μm), the best protocol is found to be 65-200 ms pulses applied over 2 min

  6. In vivo assessment of catheter positioning accuracy and prolonged irradiation time on liver tolerance dose after single-fraction 192Ir high-dose-rate brachytherapy

    Directory of Open Access Journals (Sweden)

    Kropf Siegfried

    2011-09-01

    Full Text Available Abstract Background To assess brachytherapy catheter positioning accuracy and to evaluate the effects of prolonged irradiation time on the tolerance dose of normal liver parenchyma following single-fraction irradiation with 192 Ir. Materials and methods Fifty patients with 76 malignant liver tumors treated by computed tomography (CT-guided high-dose-rate brachytherapy (HDR-BT were included in the study. The prescribed radiation dose was delivered by 1 - 11 catheters with exposure times in the range of 844 - 4432 seconds. Magnetic resonance imaging (MRI datasets for assessing irradiation effects on normal liver tissue, edema, and hepatocyte dysfunction, obtained 6 and 12 weeks after HDR-BT, were merged with 3D dosimetry data. The isodose of the treatment plan covering the same volume as the irradiation effect was taken as a surrogate for the liver tissue tolerance dose. Catheter positioning accuracy was assessed by calculating the shift between the 3D center coordinates of the irradiation effect volume and the tolerance dose volume for 38 irradiation effects in 30 patients induced by catheters implanted in nearly parallel arrangement. Effects of prolonged irradiation were assessed in areas where the irradiation effect volume and tolerance dose volume did not overlap (mismatch areas by using a catheter contribution index. This index was calculated for 48 irradiation effects induced by at least two catheters in 44 patients. Results Positioning accuracy of the brachytherapy catheters was 5-6 mm. The orthogonal and axial shifts between the center coordinates of the irradiation effect volume and the tolerance dose volume in relation to the direction vector of catheter implantation were highly correlated and in first approximation identically in the T1-w and T2-w MRI sequences (p = 0.003 and p p = 0.001 and p = 0.004, respectively. There was a significant shift of the irradiation effect towards the catheter entry site compared with the planned dose

  7. Flow and wall shear stress characterization following endovascular aneurysm repair and endovascular aneurysm sealing in an infrarenal aneurysm model

    NARCIS (Netherlands)

    Boersen, Johannes T.; Groot Jebbink, Erik; Versluis, Michel; Slump, Cornelis H.; Ku, David N.; de Vries, Jean-Paul P.M.; Reijnen, Michel M.P.J.

    2017-01-01

    Background Endovascular aneurysm repair (EVAR) with a modular endograft has become the preferred treatment for abdominal aortic aneurysms. A novel concept is endovascular aneurysm sealing (EVAS), consisting of dual endoframes surrounded by polymer-filled endobags. This dual-lumen configuration is

  8. The study of hemopoietic cells. Effect of prolonged irradiation by low dose rate radiation on the hemopoiesis in the spleen of mice

    Energy Technology Data Exchange (ETDEWEB)

    Shirata, Katsutoshi; Yanai, Takanori; Yamada, Yutaka; Saitou, Mikio; Izumi, Jun; Tanaka, Satoshi; Otsu, Hiroshi; Sato, Fumiaki [Inst. for Environmental Sciences, Dept. of Radiobiology, Rokkasho, Aomori (Japan)

    2001-07-01

    For evaluation of effects of prolonged irradiation by low dose-rate ionizing radiation on the hemopoiesis of mice, SPF C3H/HeN female mice were irradiated with {sup 137}Cs {gamma}-rays with doses of 5-8 Gy at the dose rate of 20 mGy/22h-day. After irradiation, the number of hemopoietic cells contained in spleen was determined by the methods of CFU-S and CFU-GM assays, and the number of peripheral blood cells was counted. It was shown that the number of hemopoietic cells (CFU-S colonies and CFU-GM colonies) decreased as dose increased. No remarkable changes in the number of peripheral blood cells, however, were observed. (author)

  9. Estimation of mutation rates induced by large doses of gamma, proton and neutron irradiation of the X-chromosome of the nematode Panagrellus redivivus

    International Nuclear Information System (INIS)

    Denich, K.T.R.; Samoiloff, M.R.

    1984-01-01

    The radiation-resistant free-living nematode Panagrellus redivivus was used to study mutation rates in oocytes, following gamma, proton and neutron irradiation in the dose range 45-225 grays. γ-Radiation produced approximately 0.001 lethal X-chromosomes per gray over the range tested. Proton or neutron irradiation produced approximately 0.003 lethal X-chromosomes per gray at lower doses, with the mutation rate dropping to 0.001 lethal X-chromosome per gray at the higher doses. These results suggest a dose-dependent mutation-repair system. Cell lethality was also examined. γ-Radiation produced the greatest amount of cell lethality at all doses, while neutron irradiation had no cell lethal effect at any of the doses examined. (orig.)

  10. Endovascular control of haemorrhagic urological emergencies: an observational study

    Directory of Open Access Journals (Sweden)

    Thorpe Peter

    2006-09-01

    Full Text Available Abstract Background Transarterial embolisation (TAE is an effective method in control of haemorrhage irrespective of the nature of urological emergency. As the technique and technology have evolved, it is now possible to perform highly selective embolisation. The aim of this study was to critically appraise feasibility and efficacy of therapeutic TAE in control of haemorrhagic urological emergencies using selective and non-selective embolisation. Specifically, we aimed to assess the impact of timing of embolisation on the requirement of blood transfusion and long-term morphological and functional follow-up of embolised organs. Methods This is a single institutional observational study carried out between March 1992 and March 2006. Records of all patients who underwent selective and non-selective angioembolisation to control bleeding in urological emergencies were reviewed. Data on success rate, periprocedural complications, timing of embolisation, requirement of blood transfusion and the long-term morphological and functional outcomes of embolised organs was recorded. Results Fourteen patients underwent endovascular control of bleeding as a result of trauma, iatrogenic injury and spontaneous perinephric haemorrhage during a period of 14 years. All these patients would have required emergency open surgery without the option of embolisation procedure. The mean time between the first presentation and embolisation was 22 hours (range 30 minutes to 60 hours. Mean pre-embolisation transfusion requirement was 6.8 units (range 0–22 units. None of the patients with successful embolisation required post-procedural blood transfusion. Permanent haemostasis was achieved in all but one patient, who required emergency nephrectomy. There were no serious procedure related post-embolisation complications. Conclusion Endovascular control using transarterial angioembolisation is an effective method for managing haematuria or haemorrhage in urological emergencies

  11. Perioperative nursing for patients receiving endovascular therapy for ruptured abdominal aortic aneurysm

    International Nuclear Information System (INIS)

    Dong Yanfen; Pan Wei; Zhang Hongpeng; Guo Wei; Liu Xiaoping; Wei Ren

    2010-01-01

    Objective: To discuss the nursing strategy and practical measures for patients with ruptured abdominal aortic aneurysm during the perioperative period of endovascular intervention. Methods: Endovascular therapy was carried out in 34 patients with ruptured abdominal aortic aneurysm,who were encountered in our department during the period of July 1997 to September 2008. The clinical data were retrospectively analyzed and the nursing points were summarized. Results: The average hospitalization days of the 34 patients were (14 ± 5) days, the mortality rate within 30 days was 23.5% (8/34). No nursing-related complications occurred. Conclusion: A comprehensive understanding of the mechanism, development and clinical evolution of ruptured abdominal aortic aneurysm is very important for nursing care. For nursing staff, well mastering the relevant nursing technique, carefully guarding against any nursing errors and lessening patient's suffering as far as possible, all these are the task of primary importance. (authors)

  12. Aortic dissection. Basic aspects and endovascular management

    International Nuclear Information System (INIS)

    Jaramillo, Nicolas I; Alviar, Carlos I

    2005-01-01

    Treatment of thoracic aortic pathology is complicated by the morbidity associated to the surgical procedure and to the frailty of an elderly and difficult population. Surgical operation in this kind of population frequently bears a significant incidence of death and long-term disability. In an effort to reduce the incidence of negative outcomes, minimally invasive techniques in the form of endovascular stenting have been introduced during the past decade. The technology, originally described by Parodi, and initially designed for its use in abdominal aortic aneurysms, has been adapted for the treatment of thoracic aortic aneurysms. Furthermore, an improved understanding of the pathophysiology and the natural history of thoracic aortic disease as well as the analysis of the outcomes have facilitated our treatment decisions in terms of the timing for an appropriate intervention. Treatment of thoracic aortic dissection using endovascular Stent is one of the more recent advances in this condition and is receiving increasing attention, as it is a less invasive alternative to an open surgical repair. Although this technology is still innovative, significant improvements have been made lately in the design and deployment of the endovascular Stent-grafts. These prostheses have been increasingly used to treat aneurysms, dissections and traumatic ruptures, as well as giant penetrating ulcers and intramural hematomas of the descending thoracic aorta with good early and mid-term outcomes. The rareness, complexity and severity of the pathology and the theoretically high risk of complications should render the surgeon extremely cautious especially with young patients. Conceptually, the endo luminal treatment in the acute phase seems to be the solution and will probably become a preferred therapy while technical refinement is under way. Worldwide experience is growing and with this a better understanding of the indications and limitations of this innovative therapy will be

  13. Recovery of the proliferative and functional integrity of mouse bone marrow in long-term cultures established after whole-body irradiation at different doses and dose rates

    International Nuclear Information System (INIS)

    Bierkens, J.G.; Hendry, J.H.; Testa, N.G.

    1991-01-01

    Injury inflicted upon the bone marrow stroma following whole-body irradiation and its repair over a 1-year period has been assessed in murine long-term bone marrow cultures established at increasing time intervals after irradiation. Different doses at different dose rates (10 Gy at 0.05 cGy/min, 4.5 Gy and 10 Gy at 1.6 cGy/min, and 4 x 4.5 Gy [3 weeks between doses] at 60 cGy/min) were chosen so as to maximize differences in effect in the stroma. The cellularity of the adherent layer in long-term cultures established 1 month after irradiation was reduced by 40%-90% depending on the dose and dose rate. Simultaneous with the poor ability of the marrow to form adherent layers, the cumulative spleen colony-forming unit (CFU-S) and granulocyte-macrophage colony-forming cell (GM-CFC) production over a 7-week period was reduced to 0% and 30% of control cultures, respectively. The slow recovery of the adherent layer was paralleled by an increase in the numbers of CFU-S and GM-CFC in the supernatant. Cultures established from repeatedly irradiated mice performed poorly over the entire 1-year period. Whereas the regeneration of the stroma was near complete 1 year after irradiation, the CFU-S and GM-CFC levels reached only between 50% and 80% of control cultures, respectively. Also, the concentration of CFU-S and GM-CFC in the supernatant remained persistently lower in cultures established from irradiated mice as compared to control cultures. The levels of sulfated glycosaminoglycans, which have been implicated in the establishment of the functional integrity of the microenvironment, were not reduced in the adherent layers at any time after irradiation. These results indicate that the regeneration of the stroma is accompanied by an incomplete recovery of active hemopoiesis in vitro

  14. Hybrid Endovascular Aortic Aneurysm Repair: Preservation of Pelvic Perfusion with External to Internal Iliac Artery Bypass.

    Science.gov (United States)

    Mansukhani, Neel A; Havelka, George E; Helenowski, Irene B; Rodriguez, Heron E; Hoel, Andrew W; Eskandari, Mark K

    2017-07-01

    was obtained in 90% of patients, and mean follow-up was 10.8 months (range: 0.5-36 months). All bypasses remained patent. Although branched graft technology continues to evolve, strategies to maintain adequate pelvic circulation are necessary to avoid the devastating complications of pelvic ischemia. We have demonstrated that a hybrid approach combining EVAR or isolated endovascular common iliac artery exclusion with a unilateral external-internal iliac bypass via a retroperitoneal approach is well tolerated with a short LOS and excellent patency rates. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Damage rates in neutron irradiated FeCo and FeCo2V ordered and disordered alloys

    International Nuclear Information System (INIS)

    Riviere, J.P.; Dinhut, J.F.

    1979-01-01

    Ordered and disordered samples of FeCo and FeCo2V alloys have been irradiated at liquid hydrogen temperature with fission neutrons up to an integrated dose of about 7.2 x 10 17 n/cm 2 (E > 1 MeV). During the irradiation, the resistivity increases continuously due to point defect production. (author)

  16. Endovascular aneurysm repair (EVAR) follow-up imaging: the assessment and treatment of common postoperative complications

    International Nuclear Information System (INIS)

    Ilyas, S.; Shaida, N.; Thakor, A.S.; Winterbottom, A.; Cousins, C.

    2015-01-01

    Endovascular abdominal aortic aneurysm repair (EVAR) is a well-established procedure, which has long-term mortality rates similar to that of open repair. It has the additional benefit of being less invasive, making it the favoured method of treating abdominal aortic aneurysms in elderly and high-risk patients with multiple co-morbidities. The main disadvantage of EVAR is the higher rate of re-intervention, due to device-related complications, including endoleaks, limb occlusion, stent migration, kinking, and infection. As a result lifelong surveillance is required. In order to avoid missing these complications, intricate knowledge of stent graft design, good-quality diagnostic ultrasound skills, multiplanar reformatting of CT images, and reproducible investigations are important. Most of these complications can be treated via an endovascular approach using cuff extensions, uncovered stents, coils, and liquid embolic agents. Open surgery is reserved for complex complications, where an endovascular approach is not feasible. - Highlights: • Comprehensive pictorial review of EVAR related complications. • Importance of life-long EVAR surveillance, to prevent aortic rupture or lower limb ischaemia. • Identification and management of endoleaks, rupture, migration, kink/infolding, occlusion and infection

  17. Endovascular repair of early rupture of Dacron aortic graft--two case reports.

    LENUS (Irish Health Repository)

    Sultan, Sherif

    2005-01-01

    Complications after open aortic surgery pose a challenge both to the vascular surgeon and the patient because of aging population, widespread use of cardiac revascularization, and improved survival after aortic surgery. The perioperative mortality rate for redo elective aortic surgery ranges from 5% to 29% and increases to 70-100% in emergency situation. Endovascular treatment of the postaortic open surgery (PAOS) patient has fewer complications and a lower mortality rate in comparison with redo open surgical repair. Two cases of ruptured abdominal aortic aneurysm (AAA) were managed with the conventional open surgical repair. Subsequently, spiral contrast computer tomography scans showed reperfusion of the AAA sac remnant mimicking a type III endoleak. These graft-related complications presented as vascular emergencies, and in both cases endovascular aneurysm repair (EVAR) procedure was performed successfully by aortouniiliac (AUI) stent graft and femorofemoral crossover bypass. These 2 patients add further merit to the cases reported in the English literature. This highlights the crucial importance of endovascular grafts in the management of such complex vascular problems.

  18. Midterm results of endovascular treatment of iliac artery lesions: analysis of 59 cases

    Directory of Open Access Journals (Sweden)

    Leonardo Ghizoni Bez

    2013-06-01

    Full Text Available BACKGROUND: Endovascular treatment of peripheral arterial occlusive disease has become increasingly frequent in the past few years. Because it is a less invasive procedure, lower morbidity and mortality rates are associated with this form of treatment. OBJECTIVES: To describe the endovascular procedures performed in iliac arteries for the treatment of peripheral arterial occlusive disease. METHODS: This retrospective study assesses 59 cases of iliac artery angioplasty performed according to a specific protocol from January 2004 to February 2010. RESULTS: Mean age of patients was 62 years (minimum: 42, maximum: 89. Thirty seven were male (62.72% and 22 female (37.28%. The main indications for treatment were moderate to severe intermittent claudication in 30 cases (50.84% and rest pain or trophic lesions (critical ischemia in 29 cases (49.15%. Postoperative follow-up included ankle-brachial index measurements and a duplex ultrasound at 30 days, 3 months, 6 months, 12 months, and every 6 months thereafter. Minimum follow-up time was 3 months, and maximum, 72 months (6 years, with primary and secondary patency rates of 91.37 and 94.82%, respectively. CONCLUSIONS: The results of this case series, combined with literature review results, allow to conclude that the endovascular approach is an effective and safe option to treat peripheral arterial occlusive disease in iliac arteries.

  19. Unilateral versus bilateral irradiation in squamous cell head and neck cancer in relation to patient-rated xerostomia and sticky saliva

    NARCIS (Netherlands)

    Jellema, Anke Petra; Slotman, Ben J.; Doornaert, Patricia; Leemans, C. Rene; Langendijk, Johannes A.

    2007-01-01

    Background and purpose: To investigate the association between radiation technique with patient-rated moderate and severe xerostomia and sticky saliva. Materials and methods: One hundred and fifty patients treated with bilateral or unilateral irradiation for head and neck cancer were included. The

  20. Up-regulation of calreticulin in mouse liver tissues after long-term irradiation with low-dose-rate gamma rays.

    Science.gov (United States)

    Yi, Lan; Hu, Nan; Yin, Jie; Sun, Jing; Mu, Hongxiang; Dai, Keren; Ding, Dexin

    2017-01-01

    The biological effects of low-dose or low-dose-rate ionizing radiation on normal tissues has attracted attention. Based on previous research, we observed the morphology of liver tissues of C57BL/6J mice that received irradiation dose rates increased. Additionally, differential protein expression in liver tissues was analyzed using a proteomics approach. Compared with the matched group in the 2D gel analysis of the irradiated groups, 69 proteins had ≥ 1.5-fold changes in expression. Twenty-three proteins were selected based on ≥2.5-fold change in expression, and 22 of them were meaningful for bioinformatics and protein fingerprinting analysis. These molecules were relevant to cytoskeleton processes, cell metabolism, biological defense, mitochondrial damage, detoxification and tumorigenesis. The results from real-time PCR and western blot (WB) analyses showed that calreticulin (CRT) was up-regulated in the irradiated groups, which indicates that CRT may be relevant to stress reactions when mouse livers are exposed to low-dose irradiation and that low-dose-rate ionizing radiation may pose a cancer risk. The CRT protein can be a potential candidate for low-dose or low-dose-rate ionizing radiation early-warning biomarkers. However, the underlying mechanism requires further investigation.

  1. Bystander Effects Induced by Continuous Low-Dose-Rate 125I Seeds Potentiate the Killing Action of Irradiation on Human Lung Cancer Cells In Vitro

    International Nuclear Information System (INIS)

    Chen, H.H.; Jia, R.F.; Yu, L.; Zhao, M.J.; Shao, C.L.; Cheng, W.Y.

    2008-01-01

    Purpose: To investigate bystander effects of low-dose-rate (LDR) 125 I seed irradiation on human lung cancer cells in vitro. Methods and Materials: A549 and NCI-H446 cell lines of differing radiosensitivity were directly exposed to LDR 125 I seeds irradiation for 2 or 4 Gy and then cocultured with nonirradiated cells for 24 hours. Induction of micronucleus (MN), γH2AX foci, and apoptosis were assayed. Results: After 2 and 4 Gy irradiation, micronucleus formation rate (MFR) and apoptotic rate of A549 and NCI-H446 cells were increased, and the MFR and apoptotic rate of NCI-H446 cells was 2.1-2.8 times higher than that of A549 cells. After coculturing nonirradiated bystander cells with 125 I seed irradiated cells for 24 hours, MFR and the mean number of γH2AX foci/cells of bystander A549 and NCI-H446 cells were similar and significantly higher than those of control (p 125 I seeds could induce bystander effects, which potentiate the killing action on tumor cells and compensate for the influence of nonuniform distribution of radiation dosage on therapeutic outcomes

  2. Endovascular Tubular Stent-Graft Placement for Isolated Iliac Artery Aneurysms

    International Nuclear Information System (INIS)

    Okada, Takuya; Yamaguchi, Masato; Kitagawa, Atsushi; Kawasaki, Ryota; Nomura, Yoshikatsu; Okita, Yutaka; Sugimura, Kazuro; Sugimoto, Koji

    2012-01-01

    Purpose: To evaluate the safety, efficacy, and mid-term outcomes of endovascular tubular stent-graft placement for repair of isolated iliac artery aneurysms (IAAs). Materials and Methods: Between January 2002 and March 2010, 20 patients (7 women and 13 men; mean age 74 years) underwent endovascular repair of 22 isolated IAAs. Two patients underwent endovascular repair for bilateral aneurysms. Ten para-anastomotic aneurysms (45%) developed after open abdominal aortic aneurysm (AAA) repair with an aorto-iliac graft, and 12 were true aneurysms (55%). Eleven straight and 11 tapered stent-grafts were placed. Contrast-enhanced computed tomography (CT) was performed to detect complications and evaluate aneurysmal shrinkage at week 1, 3, 6, and 12 months and once every year thereafter. Non–contrast-enhanced CT was performed in seven patients with chronic kidney disease. Results: All procedures were successful, without serious complications, during the mean (range) follow-up period of 746 days (47–2651). Type II endoleak not requiring treatment was noted in one patient. The mean (SD) diameters of the true and para-anastomotic aneurysms significantly (p < 0.05) decreased from 42.0 (9.3) to 36.9 (13.6) mm and from 40.1 (13.0) to 33.6 (15.8) mm, respectively; the mean (SD) shrinkage rates were 15.1% (20.2%) and 18.9% (22.4%), respectively. The primary patency rate was 100%, and no secondary interventions were required. Four patients (21%) developed transient buttock claudication, and one patient (5%) developed colorectal ischaemia, which was treated conservatively. Conclusion: Endovascular tubular stent-graft placement for the repair of isolated IAAs is safe and efficacious. Tapered stent-grafts of various sizes are required for accurate placement.

  3. Endovascular Management of True Renal Arterial Aneurysms: Results from a Single Centre

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Raymond, E-mail: chung.raymond.jh@alexandrahealth.com.sg [Khoo Teck Puat Hospital, Department of Radiology (Singapore); Touska, Philip, E-mail: p.touska@doctors.org.uk [St. George’s Hospital NHS Trust, Department of Radiology (United Kingdom); Morgan, Robert; Belli, Anna-Maria [St. George’s Hospital NHS Trust, Department of Interventional Radiology (United Kingdom)

    2016-01-15

    PurposeTo report a single centre’s experience of the endovascular treatment of renal arterial aneurysms, including techniques and outcomes.Materials and MethodsThis is a retrospective analysis of true renal arterial aneurysms (TRAAs) treated using endovascular techniques over a period of 12 years and 10 months. The clinical presentations, aneurysm characteristics, endovascular techniques and outcomes are reported.ResultsThere were nine TRAA cases with a mean aneurysm size of 21.0 mm, located at the main renal arterial bifurcation in all cases. Onyx{sup ®} was used as the embolic agent of choice (88.9 % cases), with concurrent balloon remodelling. The overall primary technical success rate was 100 %. Repeat intervention was carried out in 1 case, secondary to reperfusion >8 years post-initial treatment. Long-term clinical follow-up was available in 55.6 % of cases (mean 29.8 months; range 3.3–90.1 months). Early post-procedural renal function, as measured by serum creatinine, remained within the normal reference range. Renal parenchymal loss post-embolisation was ≤20 % in 77.8 % of cases, as estimated on imaging. Minor complications included non-target embolization of Onyx{sup ®} with no clinical sequelae (n = 1), transient pain requiring only oral analgesia with no prolongation of hospital stay (n = 2). No major complications occurred as a consequence of embolisation.ConclusionEndovascular therapy is an effective and safe primary therapy for TRAA with high success rate and low morbidity, supplanting surgery as primary therapy. Current experience in the use of Onyx{sup ®} in TRAA is primarily limited to individual case reports, and this represents the largest case series of Onyx{sup ®}-treated TRAAs to date.

  4. Anastomotic pseudoaneurysms after surgical reconstruction: Outcomes after endovascular repair of symptomatic versus asymptomatic patients

    International Nuclear Information System (INIS)

    Nolz, Richard; Gschwendtner, Manfred; Jülg, Gregor; Plank, Christina; Beitzke, Dietrich; Teufelsbauer, Harald; Wibmer, Andreas; Kretschmer, Georg; Lammer, Johannes

    2012-01-01

    Purpose: To compare perioperative and follow-up outcomes of symptomatic versus asymptomatic patients following endovascular repair of anastomotic pseudoaneurysms (APAs) of the abdominal aorta and iliac arteries. Methods: We retrospectively evaluated 17 patients (two women), with a mean age of 66.2 years (range 30–83 years). Endovascular treatment was performed in ten symptomatic, and seven asymptomatic patients electively. Data included technical success, perioperative (within 30 days) mortality and morbidity, as well as stent graft-related complications, reinterventions, and survival in follow-up. Results: Bifurcated (n = 13), aortomonoiliac (n = 3) endoprosthesis and one aortic cuff were implanted with a primary technical success rate of 100%. The overall in-hospital mortality and morbidity rate was 11.8% and 35.3%. The mean survival was 36.5 (range 0–111) months. There was a clear trend toward a lower overall survival within hospital and at one and three years for symptomatic patients compared to asymptomatic patients. (47.7 (CI: 0–138.8) versus 52.6 (CI: 28.5–76.8) months (p = 0.274)). During follow-up, late stent graft related complications were observed in six patients (35.3%) necessitating eight endovascular reinterventions. Additional three patients with primary fistulas between the APA and the intestine were treated by late surgical revision. Conclusion: Endovascular therapy of APAs represents a considerable alternative to open surgical repair. Short proximal anchoring zones still pose a risk for endoleaks and unintentional overstenting of side branches with commercially available devices, but this might be overcome by use of fenestrated and branched stent grafts in elective cases.

  5. RadNuc: a graphical user interface to deliver dose rate patterns encountered in nuclear medicine with a 137Cs irradiator.

    Science.gov (United States)

    Pasternack, Jordan B; Howell, Roger W

    2013-02-01

    The temporal variations in absorbed dose rates to organs and tissues in the body are very large in diagnostic and therapeutic nuclear medicine. The response of biological endpoints of relevance to radiation safety and therapeutic efficacy is generally modulated by dose rate. Therefore, it is important to understand how the complex dose rate patterns encountered in nuclear medicine impact relevant biological responses. Accordingly, a graphical user interface (GUI) was created to control a cesium-137 irradiator to deliver such dose rate patterns. Visual Basic 6.0 was used to create a user-friendly GUI to control the dose rate by varying the thickness of a mercury attenuator. The GUI facilitates the delivery of a number of dose rate patterns including constant, exponential increase or decrease, and multi-component exponential. Extensive visual feedback is provided by the GUI during both the planning and delivery stages. The GUI controlled irradiator can achieve a maximum dose rate of 40 cGy/h and a minimum dose rate of 0.01 cGy/h. Addition of machined lead blocks can be used to further reduce the minimum dose rate to 0.0001 cGy/h. Measured dose rate patterns differed from programmed dose rate patterns in total dose by 3.2% to 8.4%. The GUI controlled irradiator is able to accurately create dose rate patterns encountered in nuclear medicine and other related fields. This makes it an invaluable tool for studying the effects of chronic constant and variable low dose rates on biological tissues in the contexts of both radiation protection and clinical administration of internal radionuclides. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Evaluation of two intracavitary high-dose-rate brachytherapy devices for irradiating additional and irregularly shaped volumes of breast tissue

    International Nuclear Information System (INIS)

    Lu, Sharon M.; Scanderbeg, Daniel J.; Barna, Patrick; Yashar, William; Yashar, Catheryn

    2012-01-01

    The SAVI and Contura breast brachytherapy applicators represent 2 recent advancements in brachytherapy technology that have expanded the number of women eligible for accelerated partial breast irradiation in the treatment of early-stage breast cancer. Early clinical experience with these 2 single-entry, multichannel high-dose-rate brachytherapy devices confirms their ease of use and dosimetric versatility. However, current clinical guidelines for SAVI and Contura brachytherapy may result in a smaller or less optimal volume of treated tissue compared with traditional interstitial brachytherapy. This study evaluates the feasibility of using the SAVI and Contura to irradiate larger and irregularly shaped target volumes, approaching what is treatable with the interstitial technique. To investigate whether additional tissue can be treated, 17 patients treated with the SAVI and 3 with the Contura were selected. For each patient, the planning target volume (PTV) was modified to extend 1.1 cm, 1.3 cm, and 1.5 cm beyond the tumor bed cavity. To evaluate dose conformance to an irregularly shaped target volume, 9 patients treated with the SAVI and 3 with the Contura were selected from the original 20 patients. The following asymmetric PTV margin combinations were assessed for each patient: 1.5/0.3, 1.3/0.3, and 1.1/0.3 cm. For all patients, treatment planning was performed, adopting the National Surgical Adjuvant Breast and Bowel Project guidelines, and dosimetric comparisons were made. The 6–1 and 8–1 SAVI devices can theoretically treat a maximal tissue margin of 1.5 cm and an asymmetric PTV with margins ranging from 0.3 to 1.5 cm. The 10–1 SAVI and Contura can treat a maximal margin of 1.3 cm and 1.1 cm, respectively, and asymmetric PTV with margins ranging from 0.3–1.3 cm. Compared with the Contura, the SAVI demonstrated greater dosimetric flexibility. Risk of developing excessive hot spots increased with the size of the SAVI device. Both the SAVI and Contura

  7. Endovascular repair of abdominal aortic aneurysm.

    Science.gov (United States)

    Paravastu, Sharath Chandra Vikram; Jayarajasingam, Rubaraj; Cottam, Rachel; Palfreyman, Simon J; Michaels, Jonathan A; Thomas, Steven M

    2014-01-23

    An abnormal dilatation of the abdominal aorta is referred to as an abdominal aortic aneurysm (AAA). Due to the risk of rupture, surgical repair is offered electively to individuals with aneurysms greater than 5.5 cm in size. Traditionally, conventional open surgical repair (OSR) was considered the first choice approach. However, over the past two decades endovascular aneurysm repair (EVAR) has gained popularity as a treatment option. This article intends to review the role of EVAR in the management of elective AAA. To assess the effectiveness of EVAR versus conventional OSR in individuals with AAA considered fit for surgery, and EVAR versus best medical care in those considered unfit for surgery. This was determined by the effect on short, intermediate and long-term mortality, endograft related complications, re-intervention rates and major complications. The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (January 2013) and the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 12). The TSC also searched trial databases for details of ongoing or unpublished studies. Prospective randomised controlled trials (RCTs) comparing EVAR with OSR in individuals with AAA considered fit for surgery. and comparing EVAR with best medical care in individuals considered unfit for surgery. We excluded studies with inadequate data or using an inadequate randomisation technique. Three reviewers independently evaluated trials for appropriateness for inclusion and extracted data using pro forma designed by the Cochrane PVD Group. We assessed the quality of trials using The Cochrane Collaboration's 'Risk of bias' tool. We entered collected data in to Review Manager (version 5.2.3) for analysis. Where direct comparisons could be made, we determined odds ratios (OR). We tested studies for heterogeneity and, when present, we used a random-effects model; otherwise we used a fixed-effect model. We tabulated

  8. Comparison of Total Arch and Partial Arch Transposition During Hybrid Endovascular Repair for Aortic Arch Disease.

    Science.gov (United States)

    Kang, W C; Ko, Y-G; Oh, P C; Shin, E K; Park, C-H; Choi, D; Youn, Y N; Lee, D Y

    2016-08-01

    Total arch transposition (TAT) during hybrid endovascular repair for aortic arch disease is believed to allow a better landing zone, but also to be associated with higher peri-operative mortality than partial arch transposition (PAT). Information on this issue is limited. This study was a retrospective analysis. All 53 consecutive patients with aortic arch disease (41 males, mean age 65.0 years) who underwent hybrid endovascular repair with TAT (zone 0, n=20) or PAT (zone 1 or 2, n=33) from 2008 to 2014 were analyzed retrospectively. The peri-operative and late outcomes of these two groups were compared. Baseline characteristics, including EuroSCORE II results, were similar in the two groups. After procedures, peri-operative mortalities and stroke rates were similar in the two groups (5.0% vs. 9.1%, p=1.000, and 10.0% vs. 6.1%, p=.627). Interestingly, all four strokes occurred in patients with a type III aortic arch irrespective of transposition type. Primary success rates (80.0% vs. 69.7%, p=.527) and type I endoleak incidences (20.0% vs. 27.3%, p=.744) were not significantly different. During follow up (mean duration 36.9 months), overall survival (89.7% vs. 87.4% at 1 year and 89.7% vs. 79.3% at 3 years; p=.375) and re-intervention free survival rates (78.6% vs. 92.0% at 1 year; 72.0% vs. 62.2% at 3 years, p=.872) were similar in the two groups. Morbidity and mortality were high within the first year of hybrid endovascular therapy for aortic arch disease, implying that candidates for hybrid procedures need to be selected carefully. Hybrid endovascular repair with TAT was found to have peri-operative mortality, stroke, and long-term survival rates comparable with PAT, so hybrid endovascular repair may be considered, irrespective of type of arch reconstruction, when clinically indicated. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Endovascular brachytherapy to prevent restenosis after angioplasty

    International Nuclear Information System (INIS)

    Wohlgemuth, W.A.; Bohndorf, K.

    2003-01-01

    Endovascular radiotherapy is the first effective prophylaxis of restenosis after percutaneous transluminal angioplasty (PTA) and stenting. The FDA recently approved two devices for the delivery of intracoronary radiation following coronary artery stenting. Published multicenter, double-blind, randomized trials of intracoronary radiation therapy report good results for preventing in-stent restenosis, while the data for the peripheral circulation are still inconclusive. Beta-emitters are easier applicable and probably also safer, whereas gamma-emitters have been more extensively evaluated clinically so far. Primary indication for endovascular brachytherapy are patients at high risk for restenosis, such as previous restenoses, in-stent hyperplasia, long stented segment, long PTA lesion, narrow residual vascular lumen and diabetes. Data from coronary circulation suggest a safety margin of at least 4 to 10 mm at both ends of the angioplastic segment to avoid edge restenosis. To prevent late thrombosis of the treated coronary segment, antiplatelet therapy with clopidogrel and aspirin are recommended for at least 6 months after PTA and for 12 months after a newly implanted stent. An established medication regimen after radiotherapy of peripheral arteries is still lacking. (orig.) [de

  10. Endovascular strategy for unruptured cerebral aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Mangiafico, S., E-mail: mangiax@libero.it [Interventional Neuroradiology Unit, Careggi University Hospital, Florence (Italy); Guarnieri, G., E-mail: gianluigiguarnieri@hotmail.it [Neuroradiology Service, Cardarelli Hospital, Naples (Italy); Consoli, A., E-mail: onemed21@gmail.com [Interventional Neuroradiology Unit, Careggi University Hospital, Florence (Italy); Ambrosanio, G., E-mail: gambros@libero.it [Neuroradiology Service, Cardarelli Hospital, Naples (Italy); Muto, M., E-mail: mutomar@tiscali.it [Neuroradiology Service, Cardarelli Hospital, Naples (Italy)

    2013-10-01

    The treatment of unruptured intracranial aneurysms (UIAs) remains complex and not clearly defined. While for ruptured intracranial aneurysms the management and the treatment option (surgery or endovascular treatment) are well defined by several trials, for asymptomatic UIAs the best management is still currently uncertain. The rationale to treat an UIA is to prevent the rupture and its consequent SAH and all complications derived from hemorrhage or reduce/eliminate neurological palsy. Although this statement is correct, the indication to treat an UIA should be based on a correct balance between the natural history of UIA and treatment risk. Patient's clinical history, aneurysm characteristics, and strategy management influence the natural history of UIAs and treatment outcomes. In the last 10 years and more, two important large multicenter studies were performed in order to analysis of all these factors and to evaluate the best treatment option for UIAs. The aim of this paper is to try to synthesize the possible indications to the endovascular treatment (EVT), when and how to treat an UIA.

  11. Endovascular Management of Central Retinal Arterial Occlusion.

    Science.gov (United States)

    Agarwal, Nitin; Gala, Nihar B; Baumrind, Benjamin; Hansberry, David R; Thabet, Ahmad M; Gandhi, Chirag D; Prestigiacomo, Charles J

    2016-11-01

    Central retinal artery occlusion (CRAO) is an ophthalmologic emergency due to the sudden cessation of circulation to the inner retinal layer. Without immediate treatment, permanent blindness may ensue. Several treatment options exist, ranging from noninvasive medical management to thrombolysis. Nonetheless, ongoing debate exists regarding the best therapeutic strategy. The authors present the case of a 78-year-old woman with a medical history of hypercholesterolemia and rheumatoid arthritis who experienced complete loss of vision in her left eye. Following ophthalmologic evaluation demonstrating left CRAO, anterior chamber paracentesis was performed. Endovascular intervention was performed via local intra-arterial fibrinolysis with alteplase. Her vision returned to 20/20 following the procedure. In general, conventional therapies have not significantly improved patient outcomes. Several management options exist for CRAO. In general, conservative measures have not been reported to yield better patient outcomes as compared to the natural history of this medical emergency. Endovascular approaches are another option as observed with this case reported. In cases of CRAO, therapeutic strategies such as intra-arterial fibrinolysis utilize a local infusion of reactive tissue plasminogen activator directly at the site of occlusion via catheterization of the ophthalmic artery. Although several case series do show promising results after treating CRAO with intra-arterial fibrinolysis, further studies are required given the reports of complications.

  12. Endovascular Interventions for the Morbidly Adherent Placenta

    Directory of Open Access Journals (Sweden)

    Claire Kaufman

    2018-05-01

    Full Text Available Morbidly adherent placentas are a spectrum of abnormalities ranging from placental invasion of the myometrium to invasion past the myometrium and muscular layers into adjacent structures. This entity is becoming more prevalent recently with increased number of cesarean deliveries. Given the high risk of morbidity and mortality, this was traditionally treated with pre-term planned cesarean hysterectomy. However, recently, uterine preservation techniques have been implemented for those women wishing to preserve future fertility or their uterus. Early identification is crucial as studies have shown better outcomes for women treated at tertiary care facilities by a dedicated multidisciplinary team. Interventional radiologists are frequently included in the care of these patients as there are several different endovascular techniques which can be implemented to decrease morbidity in these patients both in conjunction with cesarean hysterectomy and in the setting of uterine preservation. This article will review the spectrum of morbidly adherent placentas, imaging, as well as the surgical and endovascular interventions implemented in the care of these complex patients.

  13. Emergency endovascular coiling of a ruptured giant splenic artery aneurysm

    Directory of Open Access Journals (Sweden)

    Erika Wernheden, MD

    2017-12-01

    Full Text Available Splenic artery aneurysms (SAAs are the third most common abdominal aneurysm. Endovascular treatment of SAAs is preferred, and coiling is the most commonly used technique. Ruptured giant (>5 cm SAAs are usually treated with open surgery including splenectomy. We present a rare case of a ruptured 15-cm giant SAA in an 84-year-old woman treated successfully with emergency endovascular coiling. To our knowledge, this is one of the few reports of emergency endovascular treatment for ruptured giant SAA.

  14. Endovascular treatment of basilar and ICA termination aneurysms: effects of the use of HydroCoils on treatment stability in a subgroup of patients prone to a higher recurrence rate

    International Nuclear Information System (INIS)

    Geyik, Serdar; Yavuz, Kivilcim; Cekirge, Saruhan; Saatci, Isil

    2007-01-01

    The aim of this study was to evaluate the stability of occlusion of terminal bifurcation aneurysms after embolization with hydrogel-coated coils. Of 35 bifurcation aneurysms, 34 were treated with hydrogel-coated coils in combination with platinum coils, and 1 was treated with hydrogel-coated coils only. Aneurysms were located at the basilar tip in 17 patients, and the internal carotid artery (ICA) bifurcation in 18 patients. The patient population consisted of 20 women and 15 men with ages ranging from 21 to 65 years. The aneurysm was found in 16 patients on presentation for subarachnoid hemorrhage, and in 19 patients the finding was incidental. Of the 35 aneurysms, 25 were small, 9 were large and 1 was giant. The giant aneurysm was located at the basilar tip and showed partial thrombosis. All except two basilar tip aneurysms were treated with balloon assistance. The remaining two basilar tip aneurysms were embolized with the assistance of an aneurysmal neck bridge device. The mean percentage occluded aneurysm volume for all devices was in the range 34-100%. Follow-up angiograms were obtained at 1 year in 6 patients, 2 years in 11 patients, and 3 years in 18 patients. Angiograms obtained immediately after embolization demonstrated a Raymond class 1 occlusion in 29 patients (82.9%) and a Raymond class 2 occlusion in 6 patients (17.1%). In four of these six patients follow-up angiograms demonstrated regrowth with resultant Raymond class 3 occlusion. In the other two patients, Raymond class 2 occlusion remained stable on follow-up angiograms. In patients who had a Raymond class 1 occlusion on the angiogram obtained immediately after embolization, no regrowth was seen on the follow-up angiograms. The overall recanalization rate was 11.4% (three large, one giant) at 6 months. Retreatment was not considered in three of these patients and they were to be followed; the other patient was retreated. Our initial procedural data demonstrate that higher volumetric occlusion was

  15. Endovascular treatment of basilar and ICA termination aneurysms: effects of the use of HydroCoils on treatment stability in a subgroup of patients prone to a higher recurrence rate

    Energy Technology Data Exchange (ETDEWEB)

    Geyik, Serdar; Yavuz, Kivilcim; Cekirge, Saruhan; Saatci, Isil [Hacettepe University Hospital, Interventional Neuroradiology Unit, Radiology Department, Ankara (Turkey)

    2007-12-15

    The aim of this study was to evaluate the stability of occlusion of terminal bifurcation aneurysms after embolization with hydrogel-coated coils. Of 35 bifurcation aneurysms, 34 were treated with hydrogel-coated coils in combination with platinum coils, and 1 was treated with hydrogel-coated coils only. Aneurysms were located at the basilar tip in 17 patients, and the internal carotid artery (ICA) bifurcation in 18 patients. The patient population consisted of 20 women and 15 men with ages ranging from 21 to 65 years. The aneurysm was found in 16 patients on presentation for subarachnoid hemorrhage, and in 19 patients the finding was incidental. Of the 35 aneurysms, 25 were small, 9 were large and 1 was giant. The giant aneurysm was located at the basilar tip and showed partial thrombosis. All except two basilar tip aneurysms were treated with balloon assistance. The remaining two basilar tip aneurysms were embolized with the assistance of an aneurysmal neck bridge device. The mean percentage occluded aneurysm volume for all devices was in the range 34-100%. Follow-up angiograms were obtained at 1 year in 6 patients, 2 years in 11 patients, and 3 years in 18 patients. Angiograms obtained immediately after embolization demonstrated a Raymond class 1 occlusion in 29 patients (82.9%) and a Raymond class 2 occlusion in 6 patients (17.1%). In four of these six patients follow-up angiograms demonstrated regrowth with resultant Raymond class 3 occlusion. In the other two patients, Raymond class 2 occlusion remained stable on follow-up angiograms. In patients who had a Raymond class 1 occlusion on the angiogram obtained immediately after embolization, no regrowth was seen on the follow-up angiograms. The overall recanalization rate was 11.4% (three large, one giant) at 6 months. Retreatment was not considered in three of these patients and they were to be followed; the other patient was retreated. Our initial procedural data demonstrate that higher volumetric occlusion was

  16. Flow and wall shear stress characterization after endovascular aneurysm repair and endovascular aneurysm sealing in an infrarenal aneurysm model.

    Science.gov (United States)

    Boersen, Johannes T; Groot Jebbink, Erik; Versluis, Michel; Slump, Cornelis H; Ku, David N; de Vries, Jean-Paul P M; Reijnen, Michel M P J

    2017-12-01

    Endovascular aneurysm repair (EVAR) with a modular endograft has become the preferred treatment for abdominal aortic aneurysms. A novel concept is endovascular aneurysm sealing (EVAS), consisting of dual endoframes surrounded by polymer-filled endobags. This dual-lumen configuration is different from a bifurcation with a tapered trajectory of the flow lumen into the two limbs and may induce unfavorable flow conditions. These include low and oscillatory wall shear stress (WSS), linked to atherosclerosis, and high shear rates that may result in thrombosis. An in vitro study was performed to assess the impact of EVAR and EVAS on flow patterns and WSS. Four abdominal aortic aneurysm phantoms were constructed, including three stented models, to study the influence of the flow divider on flow (Endurant [Medtronic, Minneapolis, Minn], AFX [Endologix, Irvine, Calif], and Nellix [Endologix]). Experimental models were tested under physiologic resting conditions, and flow was visualized with laser particle imaging velocimetry, quantified by shear rate, WSS, and oscillatory shear index (OSI) in the suprarenal aorta, renal artery (RA), and common iliac artery. WSS and OSI were comparable for all models in the suprarenal aorta. The RA flow profile in the EVAR models was comparable to the control, but a region of lower WSS was observed on the caudal wall compared with the control. The EVAS model showed a stronger jet flow with a higher shear rate in some regions compared with the other models. Small regions of low WSS and high OSI were found near the distal end of all stents in the common iliac artery compared with the control. Maximum shear rates in each region of interest were well below the pathologic threshold for acute thrombosis. The different stent designs do not influence suprarenal flow. Lower WSS is observed in the caudal wall of the RA after EVAR and a higher shear rate after EVAS. All stented models have a small region of low WSS and high OSI near the distal outflow

  17. Outcome after endovascular therapy of ruptured intracranial aneurysms: morbidity and impact of rebleeding

    International Nuclear Information System (INIS)

    Kremer, C.; Groden, C.; Zeumer, H.; Lammers, G.; Weineck, G.; Hansen, H.C.

    2002-01-01

    We evaluated midterm functional outcome after endovascular occlusion of aneurysms in patients with subarachnoid haemorrhage (SAH) and determined the incidence of late rebleeding as an additional prognostic parameter. We treated 79 consecutive patients with SAH from an intracranial aneurysm admitted from a neurological intensive care unit by the endovascular route between 1993 and 1997 and 52 survivors were followed up in 1999-2000. The mean interval between SAH and follow-up was 41 months (range 13-74 months). Outcome was determined by the Glasgow outcome (GOS) and Rankin (RS) scales and by questions concerning neuropsychological disorders. The patients were analysed according to Hunt and Hess (H and H) grades I-III or IV-V on admission. We observed two episodes of rebleeding (3%) with impact on outcome at 907 and 2010 days after SAH, respectively. A complete recovery (GOS 5) was achieved in 53% of H and H grade I-III and 17% of grade IV-V patients; with death rates 19% and 50%, and morbidity according to the RS (5-2) 18% and 29%, respectively. Midterm morbidity after endovascular therapy is thus low. Rebleeding with an impact on outcome can be observed up to 2010 days after SAH, suggesting that long-term angiographic follow-up is indispensable. (orig.)

  18. Penetrating Atherosclerotic Ulcer of the Descending Thoracic Aorta: Treatment by Endovascular Stent-Graft

    International Nuclear Information System (INIS)

    Murgo, Salvatore; Dussaussois, Luc; Golzarian, Jafar; Cavenaile, Jean Christophe; Abada, Hicham Tarik; Ferreira, Jose; Struyven, Julien

    1998-01-01

    Purpose: To present four cases of penetrating ulcer of the descending thoracic aorta treated by transfemoral insertion of an endoluminal stent-graft. Methods: Four patients with penetrating aortic ulcers were reviewed. Three cases were complicated by rupture, false aneurysm, or retrograde dissection. All patients were treated by endovascular stent-graft and were followed by helical computed tomography (CT). Results: Endovascular stent-graft deployment was successful in all patients. However, in one case we observed a perigraft leak that spontaneously disappeared within the first month, and two interventions were needed for another patient. Following treatment, one episode of transient spinal ischemia was observed. The 30-day survival rate was 100%, but one patient died from pneumonia with cardiac failure 34 days after the procedure. In one patient, helical CT performed at 3 months showed a false aneurysm independent of the first ulcer. This patient refused any further treatment and suddenly died at home (unknown cause) after a 6-month follow-up period. Conclusion: Transluminal placement of endovascular stent-grafts for treatment of penetrating ulcers of the descending thoracic aorta appears to be a possible alternative to classical surgery. After treatment, follow-up by CT is essential to detect possible complications of the disease

  19. Mid- and Long-Term Results of Endovascular Treatment in Thoracic Aorta Blunt Trauma

    Directory of Open Access Journals (Sweden)

    Luigi Irace

    2012-01-01

    Full Text Available Study Aim. Evaluation of results in blunt injury of the thoracic aorta (BAI endovascular treatment. Materials and Methods. Sixteen patients were treated for BAI. Thirteen patients had associated polytrauma, 4 of these had a serious hypotensive status and 4 had an hemothorax. In the remaining 3, two had a post-traumatic false aneurysm of the isthmus and 1 had a segmental dissection. In those 13 patients a periaortic hematoma was associated to hemothorax in 4. All patients were submitted to an endovascular treatment, in two cases the subclavian artery ostium was intentionally covered. Results. One patient died for disseminated intravascular coagulation. No paraplegia was recorded. No ischemic complications were observed. A type I endoleak was treated by an adjunctive cuff. During the followup (1–9 years 3 patients were lost. A good patency and no endoleaks were observed in all cases. One infolding and 1 migration of the endografts were corrected by an adjunctive cuff. Conclusion. The medium and long term results of the endovascular treatment of BAI are encouraging with a low incidence rate of mortality and complications. More suitable endo-suite and endografts could be a crucial point for the further improvement of these results.

  20. Endovascular Treatment of Malignant Superior Vena Cava Syndrome: Results and Predictive Factors of Clinical Efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Fagedet, Dorothee, E-mail: DFagedet@chu-grenoble.fr [CHU de Grenoble, Clinique universitaire de medecine interne, Pole Pluridisciplinaire de Medecine (France); Thony, Frederic, E-mail: FThony@chu-grenoble.fr [CHU de Grenoble, Clinique universitaire de radiologie et imagerie medicale, Pole d' Imagerie (France); Timsit, Jean-Francois, E-mail: JFTimsit@chu-grenoble.fr [CHU de Grenoble, Clinique universitaire de reanimation, Pole Medecine Aiguee Communautaire (France); Rodiere, Mathieu, E-mail: MRodiere@chu-grenoble.fr [CHU de Grenoble, Clinique universitaire de radiologie et imagerie medicale, Pole d' Imagerie (France); Monnin-Bares, Valerie, E-mail: v-monnin@chu-montpellier.fr [CHRU Arnaud de Villeneuve, Imagerie Medicale Thoracique Cardiovasculaire (France); Ferretti, Gilbert R., E-mail: GFerretti@chu-grenoble.fr [CHU de Grenoble, Clinique universitaire de radiologie et imagerie medicale, Pole d' Imagerie (France); Vesin, Aurelien; Moro-Sibilot, Denis, E-mail: DMoro.pneumo@chu-grenoble.fr [University Grenoble 1 e Albert Bonniot Institute, Inserm U823 (France)

    2013-02-15

    To demonstrate the effectiveness of endovascular treatment (EVT) with self-expandable bare stents for malignant superior vena cava syndrome (SVCS) and to analyze predictive factors of EVT efficacy. Retrospective review of the 164 patients with malignant SVCS treated with EVT in our hospital from August 1992 to December 2007 and followed until February 2009. Endovascular treatment includes angioplasty before and after stent placement. We used self-expandable bare stents. We studied results of this treatment and looked for predictive factors of clinical efficacy, recurrence, and complications by statistical analysis. Endovascular treatment was clinically successful in 95% of cases, with an acceptable rate of early mortality (2.4%). Thrombosis of the superior vena cava was the only independent factor for EVT failure. The use of stents over 16 mm in diameter was a predictive factor for complications (P = 0.008). Twenty-one complications (12.8%) occurred during the follow-up period. Relapse occurred in 36 patients (21.9%), with effective restenting in 75% of cases. Recurrence of SVCS was significantly increased in cases of occlusion (P = 0.01), initial associated thrombosis (P = 0.006), or use of steel stents (P = 0.004). Long-term anticoagulant therapy did not influence the risk of recurrence or complications. In malignancy, EVT with self-expandable bare stents is an effective SVCS therapy. These results prompt us to propose treatment with stents earlier in the clinical course of patients with SVCS and to avoid dilatation greater than 16 mm.

  1. The Role of Multi-slice Spiral CT Angiography in Patient Management After Endovascular Therapy

    International Nuclear Information System (INIS)

    Peloschek, P.; Sailer, J.; Loewe, C.; Schillinger, M.; Lammer, J.

    2006-01-01

    Objectives. To bring out the role of multi-slice spiral CT angiography (MS-CTA) in patient management after endovascular therapy of subclavian artery stenosis. Methods. Twenty-one consecutive patients with clinically suspected restenosis after endovascular treatment of subclavian artery stenosis or occlusion were included in the study. Eleven patients had been treated with percutaneous transluminal angioplasty (PTA) alone and 10 with PTA and stenting. The mean follow-up period after PTA or stenting was 57 (±27 SD) months. CTA was performed using a bolus-triggered high-resolution protocol with biphasic intravenous contrast medium injection. Axial images and curved planar reformations (CPRs) were rated by three readers with regard to patency of supra-aortic vessels. Imaging findings were correlated with a standardized clinical assessment. Results. All examinations were of diagnostic quality. Of 21 referred patients, 7 had significant reobstruction of the treated subclavian artery. Six of the 7 patients with significant restenosis on CTA were treated conservatively (antiplatelet agents), despite 2 of them being symptomatic on the standardized clinical assessment, which showed a sensitivity and specificity of 86% in predicting stenosis. One patient was treated with PTA and stent deployment because of strong subjective suffering. Conclusion. MS-CTA is useful for exclusion or quantification of clinically suspected restenosis in carefully selected patients after endovascular therapy where ultrasound is inconclusive and/or contrast-enhanced magnetic resonance angiography is contraindicated

  2. Endovascular Treatment of Malignant Superior Vena Cava Syndrome: Results and Predictive Factors of Clinical Efficacy

    International Nuclear Information System (INIS)

    Fagedet, Dorothée; Thony, Frederic; Timsit, Jean-François; Rodiere, Mathieu; Monnin-Bares, Valérie; Ferretti, Gilbert R.; Vesin, Aurélien; Moro-Sibilot, Denis

    2013-01-01

    To demonstrate the effectiveness of endovascular treatment (EVT) with self-expandable bare stents for malignant superior vena cava syndrome (SVCS) and to analyze predictive factors of EVT efficacy. Retrospective review of the 164 patients with malignant SVCS treated with EVT in our hospital from August 1992 to December 2007 and followed until February 2009. Endovascular treatment includes angioplasty before and after stent placement. We used self-expandable bare stents. We studied results of this treatment and looked for predictive factors of clinical efficacy, recurrence, and complications by statistical analysis. Endovascular treatment was clinically successful in 95% of cases, with an acceptable rate of early mortality (2.4%). Thrombosis of the superior vena cava was the only independent factor for EVT failure. The use of stents over 16 mm in diameter was a predictive factor for complications (P = 0.008). Twenty-one complications (12.8%) occurred during the follow-up period. Relapse occurred in 36 patients (21.9%), with effective restenting in 75% of cases. Recurrence of SVCS was significantly increased in cases of occlusion (P = 0.01), initial associated thrombosis (P = 0.006), or use of steel stents (P = 0.004). Long-term anticoagulant therapy did not influence the risk of recurrence or complications. In malignancy, EVT with self-expandable bare stents is an effective SVCS therapy. These results prompt us to propose treatment with stents earlier in the clinical course of patients with SVCS and to avoid dilatation greater than 16 mm.

  3. Collateral flow as causative of good outcomes in endovascular stroke therapy.

    Science.gov (United States)

    Sheth, Sunil A; Sanossian, Nerses; Hao, Qing; Starkman, Sidney; Ali, Latisha K; Kim, Doojin; Gonzalez, Nestor R; Tateshima, Satoshi; Jahan, Reza; Duckwiler, Gary R; Saver, Jeffrey L; Vinuela, Fernando; Liebeskind, David S

    2016-01-01

    Endovascular reperfusion techniques are a promising intervention for acute ischemic stroke (AIS). Prior studies have identified markers of initial injury (arrival NIH stroke scale (NIHSS) or infarct volume) as predictive of outcome after these procedures. We sought to define the role of collateral flow at the time of presentation in determining the extent of initial ischemic injury and its influence on final outcome. Demographic, clinical, laboratory, and radiographic data were prospectively collected on a consecutive cohort of patients who received endovascular therapy for acute cerebral ischemia at a single tertiary referral center from September 2004 to August 2010. Higher collateral grade as assessed by the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grading scheme on angiography at the time of presentation was associated with improved reperfusion rates after endovascular intervention, decreased post-procedural hemorrhage, smaller infarcts on presentation and discharge, as well as improved neurological function on arrival to the hospital, discharge, and 90 days later. Patients matched by vessel occlusion, age, and time of onset demonstrated smaller strokes on presentation and better functional and radiographic outcome if found to have superior collateral flow. In multivariate analysis, lower collateral grade independently predicted higher NIHSS on arrival. Improved collateral flow in patients with AIS undergoing endovascular therapy was associated with improved radiographic and clinical outcomes. Independent of age, vessel occlusion and time, in patients with comparable ischemic burdens, changes in collateral grade alone led to significant differences in initial stroke severity as well as ultimate clinical outcome. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  4. National survey on perioperative anaesthetic management in the endovascular treatment of acute ischaemic stroke.

    Science.gov (United States)

    Romero Kräuchi, O; Valencia, L; Iturri, F; Mariscal Ortega, A; López Gómez, A; Valero, R

    2018-01-01

    To assess the anaesthetic management of treatment for endovascular acute ischaemic stroke (AIS) in Spain. A survey was designed by the SEDAR Neuroscience Section and sent to the Spanish anaesthesiology departments with a primary stroke centre between July and November 2016. Of the 47 hospitals where endovascular treatment of AIS is performed, 37 anaesthesiology departments participated. Thirty responses were obtained; three of which were eliminated due to duplication (response rate of 72.9%). Health coverage for AIS endovascular treatment was available 24hours a day in 63% of the hospitals. The anaesthesiologist in charge of the procedure was physically present in the hospital in 55.3%. There was large inter-hospital variability in non-standard monitoring and type of anaesthesia. The most important criterion for selecting type of anaesthesia was multidisciplinary choice made by the anaesthesiologist, neurologist and neuroradiologist (59.3%). The duration of time from arrival to arterial puncture was 10-15minutes in 59.2%. In 44.4%, systolic blood pressure was maintained between 140-180mmHg, and diastolic blood pressure<105mmHg. Glycaemic levels were taken in 81.5% of hospitals. Intravenous heparinisation was performed during the procedure in 66.7% with different patterns of action. In cases of moderate neurological deterioration with no added complications, 85.2% of the included hospitals awakened and extubated the patients. The wide variability observed in the anaesthetic management and the organization of the endovascular treatment of AIS demonstrates the need to create common guidelines for anaesthesiologists in Spain. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Current status and outlook of endovascular therapy for cerebral ischemic diseases

    International Nuclear Information System (INIS)

    Li Minghua; Zhao Jungong

    2005-01-01

    Improvement of diagnostic technology and increasing advent of new materials for intervention has created a new area for endovascular therapy of cerebral ischemic diseases. Current research findings have shown that endovascular thrombolysis in acute stage of cerebral infarction can accelerate the rate of re-canalization of occluded arteries and greatly decrease the morbidity and mortality of cerebral ischemic vascular diseases. Stenting of arterial stenosis can the improve of blood supply distal to the lesion, prevent recurrent cerebral ischemic stroke. As a result, endovascular thrombolysis for acute cerebral infarction and stenting for intracranial and carotid arterial stenosis are booming both at home and abroad. Proper selection of patients of acute cerebral infarction for endovascular thrombolysis with less complications could be achieved through CT perfusion, MR perfusion-weighted image (PWI) and diffusion-weighted image (DWI), non-invasive vascular imaging technology including CEMRA and CTA for confirming and demonstrating the sites and causes of cerebral ischemia, and furthermore for evaluating the survival ability and etc. The research team administered albumin and magnesium sulfate as neurological protection drug to treat rat infarction model within 6 hours of onset resulting with the same effect of decreasing the damage of ischemic cerebral tissue and without hemorrhagic complication. It is certain that hemorrhagic complication in thrombolysis is a result of multiple factors with no single drug being able to solve the problem. It is predictable that, based on semi-quantitative or quantitative parameters of CT or MRI in conjunction with PWI/DWI mismatch model rather than simply on the onset time of infarction for proper selection of patients of cerebral infarction, mechanic thrombus-disruption and/or intra-arterial thrombolysis together with intervention of neurological protection drug will be the trend for treating acute cerebral infarction in the future

  6. On the development of neoplasma in dogs after chronic gamma-irradiation at a low dose rate

    International Nuclear Information System (INIS)

    Yakovleva, V.I.

    1978-01-01

    In order to estimate end effects of chronic prolonged gamma irradiation of dogs, an exposure of 80 animals to irradiation was terminated and they were followed up closely. Out of 80 animals 30 dogs (Ist series) were irradiated for 3 years and 50 dogs (2 series) for 6 years. The dogs were exposed to irradiation at doses of 21 to 190 rad per year. Out of the total number of animals 22 dogs died. Post-mortem examinations showed neoplasms in 13 animals (7 malignant and 12 benign neoplasms). The highest number of tumors developed in dogs of the 2 series (10 out of 11) one-two years after irradiation (6 malignant tumors-malignant pheochro--mocytoma of adrenals; malignant adenoma of the hypophysis: polymorphocellular sarcoma of the liver; leucomyosarcoma of the uterus; blader cancer; breast cancer; and 10 benign tumors-pancreatic adenoma; liver angioma; 2 papillary adenomas of the prostate; 3 renal adenomas; lipoma; polyps of the gall-bladder). Animals of the 1-st series displayed 3 neoplasms (1 malignant tumor-bladder tumor and 2 benign tumors-liver hepatoma and spleen angioma) 4-5 years after irradiation

  7. Changes in hemopoiesis of mice during chronic irradiation with a dose rate of 957 mGy/day

    International Nuclear Information System (INIS)

    Mackova, N.; Marko, L.; Horak, J.

    1982-01-01

    Quantitative and qualitative changes in the blood producing organs and in the peripheral blood of mice were evaluated. The animals have been continually irradiated for 42 days with a daily dosage of 957 mGy. Until the 7th day of irradiation a significant diminution of the cellularity of the bone marrow and of the cellularity as well as the mass of the spleen could be observed. After the 14th day of irradiation a temporary stabilization of the cell number in the bone marrow could be found until the 28th day, after that time there was a moderately strong decrease. The cellularity and the mass of the spleen increased temporarily until the 28th day of irradiation owing to the increase of erythropoiesis and myelopoiesis from 20% to 50%. The most significant changes in the peripheral blood could be observed in agranulocytes as a kind of sudden and permanent decrease. The diminution of the granulocyte and reticulocyte numbers proceeded somewhat more slowly, with a temporarily increasing tendency on the 28th day of irradiation. The erythrocyte numbers as well as the hematocrit and hemoglobin values decreased continually beginning from the 7th day of irradiation until the death of the animals. (author)

  8. Health effects of prolonged low-dose rate gamma-irradiation of a human population in Taiwan, 1983-2003

    International Nuclear Information System (INIS)

    Chang, W. P.; Hsieh, W. A.; Lin, Y. P.; Huang, S.; Hwang, B. F.; Lee, S. D.; Chen, J. C.; Tsai, M.; Yen, N. P.

    2004-01-01

    Health effects of low dose-rate , low LET irradiation on large numbers of human population have been rare and less well known and studied. However, the standards for safety and health regulation for radiation exposure depend on solid observations of related studies. during 1983 to mid 1990s, an unusual contamination occurred that was derived from several lost Co-60 orphan sources and un-intentionally recycled into thousands tons construction steels, eventually employed for construction in several cities in Taiwan. Continuous studies on the immediate and prolonged health effects of these 7,000 subjects, with more than 60% have been exposed during prenatal, childhood, and adolescents periods, have been able to form a stron scientific avenue to provide evidences for unusual observation on a human population in natural environments. Moreover, an exposure reconstruction program, co-joined with scientists in National Institute of Occupational Safety and Health and Oregan State University in the U. S.; were initiated and continued throughout the study program that critically provided dose response analysis feasible. These studies include bone marrow/hematological changes, lens opacities, thyroid function and thyroid glands abnormalities, growth and development in physical parameters, helper and suppressor T cell populations, serum p53 protein levels, and cancer incidences and risks. Moreover, several cytogenetic markers have been employed to analyze the subtle changes in the somatic tissues. These include frequencies of micronuclei formation, chromosomal aberrations and chromosomal translocations on circulating T-lymphocytes. Functional studies including IQ testing on prenatally exposed children and the reproductive potential as time-to-pregnancy, TTP, were also observed in married couples with offspring. The observations, published in more than 20 manuscripts, will be summarized and presented for future collaborative studies, based on the established database, case

  9. Standards for Endovascular Neurosurgical Training and Certification of the Society of Korean Endovascular Neurosurgeons 2013

    Science.gov (United States)

    Shin, Dong-Seong; Park, Sukh-Que; Kang, Hyun-Seung; Yoon, Seok-Mann; Cho, Jae-Hoon; Lim, Dong-Jun; Baik, Min-Woo; Kwon, O Ki

    2014-01-01

    The need for standard endovascular neurosurgical (ENS) training programs and certification in Korea cannot be overlooked due to the increasing number of ENS specialists and the expanding ENS field. The Society of Korean Endovascular Neurosurgeons (SKEN) Certification Committee has prepared training programs and certification since 2010, and the first certificates were issued in 2013. A task force team (TFT) was organized in August 2010 to develop training programs and certification. TFT members researched programs and systems in other countries to develop a program that best suited Korea. After 2 years, a rough draft of the ENS training and certification regulations were prepared, and the standard training program title was decided. The SKEN Certification Committee made an official announcement about the certification program in March 2013. The final certification regulations comprised three major parts: certified endovascular neurosurgeons (EN), certified ENS institutions, and certified ENS training institutions. Applications have been evaluated and the results were announced in June 2013 as follows: 126 members received EN certification and 55 hospitals became ENS-certified institutions. The SKEN has established standard ENS training programs together with a certification system, and it is expected that they will advance the field of ENS to enhance public health and safety in Korea. PMID:24851145

  10. Impact peculiarities of long-term gamma-irradiation with low-dose rate on the development of laboratory rats and their sperm production

    International Nuclear Information System (INIS)

    Klepko, A.V.; Motrina, O.A.; Vatlyitsova, O.S.; And Others

    2015-01-01

    The experiments were performed on laboratory white rats of 2.5 months in age. Animals were irradiated in gamma-field of 'Ethalon' device in a dose range 0.1-1.0 Gy. Testicles, epididymices, ventral prostate were retrieved from decapitated animal, each organ weight being determined for every exposure dose. Sperm quantities in testicles and epididymices were identified with aid of phase-contrast microscopy after tissue homogenization in saline containing Triton X-100 and NaN_3. Kinetic characteristics of spermatozoa were analyzed by video recording at 37 C. The longterm gamma-irradiation with low dose rate was shown to cause no effect on the dynamics of animal weight and weight of epididymices changes. However the testes weight was noticed to diminish at doses 0.1, 0.3, 0.6 and 1.0 Gy, the latter dose being stimulative for the ventral prostate growth and weight accumulation. Total sperm quantities in testicles and epididymices along with daily sperm production declined in gamma-irradiated rats compared to control. However curvilinear and straight line spermatozoid velocity as well as the frequency of tail oscillations tended to increase. Long-term gamma-irradiation of the rat whole body with low dose rate just insignificantly affects the development of testes and ventral prostate. Apart from this, radiation effects showed up in sperm production slight suppression, from the on hand, and sperm velocity along with tail oscillations intensification, from the other hand

  11. Endovascular Management of Acute Embolic Occlusion of the Superior Mesenteric Artery: A 12-Year Single-Centre Experience

    International Nuclear Information System (INIS)

    Raupach, J.; Lojik, M.; Chovanec, V.; Renc, O.; Strýček, M.; Dvořák, P.; Hoffmann, P.; Guňka, I.; Ferko, A.; Ryška, P.; Omran, N.; Krajina, A.; Čabelková, P.; Čermáková, E.; Malý, R.

    2016-01-01

    PurposeRetrospective evaluation of 12-year experience with endovascular management of acute mesenteric ischemia (AMI) due to embolic occlusion of the superior mesenteric artery (SMA).Materials and methodsFrom 2003 to 2014, we analysed the in-hospital mortality of 37 patients with acute mesenteric embolism who underwent primary endovascular therapy with subsequent on-demand laparotomy. Transcatheter embolus aspiration was used in all 37 patients (19 women, 18 men, median age 76 years) with embolic occlusion of the SMA. Adjunctive local thrombolysis (n = 2) and stenting (n = 2) were also utilised.ResultsWe achieved complete recanalization of the SMA stem in 91.9 %. One patient was successfully treated by surgical embolectomy due to a failed endovascular approach. Subsequent exploratory laparotomy was performed in 73.0 % (n = 27), and necrotic bowel resection in 40.5 %. The total in-hospital mortality was 27.0 %.ConclusionPrimary endovascular therapy for acute embolic SMA occlusion with on-demand laparotomy is a recommended algorithm used in our centre to treat SMA occlusion. This combined approach for the treatment of AMI is associated with in-hospital mortality rate of 27.0 %

  12. Endovascular Management of Acute Embolic Occlusion of the Superior Mesenteric Artery: A 12-Year Single-Centre Experience

    Energy Technology Data Exchange (ETDEWEB)

    Raupach, J., E-mail: janraupach@seznam.cz; Lojik, M., E-mail: miroslav.lojik@fnhk.cz; Chovanec, V., E-mail: chovanec.v@seznam.cz; Renc, O., E-mail: ondrejrenc@seznam.cz [Faculty of Medicine at Charles University and University Hospital, Department of Radiology (Czech Republic); Strýček, M., E-mail: m.strycek@gmail.com [Faculty of Medicine at Charles University (Czech Republic); Dvořák, P., E-mail: petr.dvorak@fnhk.cz; Hoffmann, P., E-mail: hoffmpet@fnhk.cz [Faculty of Medicine at Charles University and University Hospital, Department of Radiology (Czech Republic); Guňka, I., E-mail: gunka@email.cz; Ferko, A., E-mail: a.ferko@seznam.cz [Faculty of Medicine at Charles University and University Hospital, Department of Surgery (Czech Republic); Ryška, P., E-mail: ryska@fnhk.cz [Faculty of Medicine at Charles University and University Hospital, Department of Radiology (Czech Republic); Omran, N., E-mail: nidal81@gmail.com [Faculty of Medicine at Charles University and University Hospital, Department of Cardiac Surgery (Czech Republic); Krajina, A., E-mail: krajina@fnhk.cz; Čabelková, P., E-mail: pavla.cabelkova@fnhk.cz [Faculty of Medicine at Charles University and University Hospital, Department of Radiology (Czech Republic); Čermáková, E., E-mail: cermakovae@lfhk.cuni.cz [Faculty of Medicine at Charles University, Computer Technology Center (Czech Republic); Malý, R., E-mail: malyr@volny.cz [Faculty of Medicine at Charles University and University Hospital, Department of Medicine (Czech Republic)

    2016-02-15

    PurposeRetrospective evaluation of 12-year experience with endovascular management of acute mesenteric ischemia (AMI) due to embolic occlusion of the superior mesenteric artery (SMA).Materials and methodsFrom 2003 to 2014, we analysed the in-hospital mortality of 37 patients with acute mesenteric embolism who underwent primary endovascular therapy with subsequent on-demand laparotomy. Transcatheter embolus aspiration was used in all 37 patients (19 women, 18 men, median age 76 years) with embolic occlusion of the SMA. Adjunctive local thrombolysis (n = 2) and stenting (n = 2) were also utilised.ResultsWe achieved complete recanalization of the SMA stem in 91.9 %. One patient was successfully treated by surgical embolectomy due to a failed endovascular approach. Subsequent exploratory laparotomy was performed in 73.0 % (n = 27), and necrotic bowel resection in 40.5 %. The total in-hospital mortality was 27.0 %.ConclusionPrimary endovascular therapy for acute embolic SMA occlusion with on-demand laparotomy is a recommended algorithm used in our centre to treat SMA occlusion. This combined approach for the treatment of AMI is associated with in-hospital mortality rate of 27.0 %.

  13. Endovascular treatment of a true posterior communicating artery aneurysm.

    Science.gov (United States)

    Munarriz, Pablo M; Castaño-Leon, Ana M; Cepeda, Santiago; Campollo, Jorge; Alén, Jose F; Lagares, Alfonso

    2014-01-01

    Posterior communicating artery (PCoA) aneurysms are most commonly located at the junction of the internal carotid artery and the PCoA. "True" PCoA aneurysms, which originate from the PCoA itself, are rarely encountered. Most previously reported cases were treated surgically mainly before the endovascular option became available. A 53-year-old male presented with sudden onset of right hemiparesis and aphasia. Left middle cerebral artery stroke was diagnosed. Further studies revealed a 3 mm left PCoA aneurysm arising from the PCoA itself, attached to neither the internal carotid artery nor the posterior cerebral artery. Endovascular treatment was performed and the aneurysm was coiled completely. Technical advances in endovascular interventional technology have permitted an additional approach to these lesions. The possible endovascular significance of the treatment of true PCoA aneurysms is discussed.

  14. Update on acute endovascular and surgical stroke treatment

    DEFF Research Database (Denmark)

    Kondziella, D; Cortsen, M; Eskesen, V

    2013-01-01

    Emergency stroke care has become a natural part of the emerging discipline of neurocritical care and demands close cooperation between the neurologist and neurointerventionists, neurosurgeons, and anesthesiologists. Endovascular treatment (EVT), including intra-arterial thrombolysis, mechanical...

  15. Endovascular Management of Vascular Injury during Transsphenoidal Surgery

    OpenAIRE

    Çinar, C.; Bozkaya, H.; Parildar, M.; Oran, I.

    2013-01-01

    Vascular injury is an unusual and serious complication of transsphenoidal surgery. We aimed to define the role of angiography and endovascular treatment in patients with vascular injuries occurring during transsphenoidal surgery.

  16. The importance of expert feedback during endovascular simulator training.

    LENUS (Irish Health Repository)

    Boyle, Emily

    2011-07-01

    Complex endovascular skills are difficult to obtain in the clinical environment. Virtual reality (VR) simulator training is a valuable addition to current training curricula, but is there a benefit in the absence of expert trainers?

  17. Hepatic vascular injury: Clinical profile, endovascular management and outcomes

    Directory of Open Access Journals (Sweden)

    Bishav Mohan

    2013-01-01

    Conclusion: Prompt endovascular management is the modality of choice in comparison to NOM without AE in both pediatric and adult patients with hemodynamically compromised inaccessible intra hepatic vascular trauma.

  18. Construct canine intracranial aneurysm model by endovascular technique

    International Nuclear Information System (INIS)

    Liang Xiaodong; Liu Yizhi; Ni Caifang; Ding Yi

    2004-01-01

    Objective: To construct canine bifurcation aneurysms suitable for evaluating the exploration of endovascular devices for interventional therapy by endovascular technique. Methods: The right common carotid artery of six dogs was expanded with a pliable balloon by means of endovascular technique, then embolization with detached balloon was taken at their originations DAS examination were performed on 1, 2, 3 d after the procedurse. Results: 6 aneurysm models were created in six dogs successfully with the mean width and height of the aneurysms decreasing in 3 days. Conclusions: This canine aneurysm model presents the virtue in the size and shape of human cerebral bifurcation saccular aneurysms on DSA image, suitable for developing the exploration of endovascular devices for aneurismal therapy. The procedure is quick, reliable and reproducible. (authors)

  19. Endovascular treatment of splenic artery aneurysms

    International Nuclear Information System (INIS)

    Lagana, Domenico; Carrafiello, Gianpaolo; Mangini, Monica; Fontana, Federico; Dizonno, Massimiliano; Fugazzola, Carlo; Castelli, Patrizio

    2005-01-01

    Purpose. To assess the feasibility and effectiveness of endovascular treatment of splenic artery aneurysm (SAAs). Materials and methods. Between May 2000 and June 2003 we treated 11 true SAAs in 9 patients (7 females and 2 males; mean age 58 years), 8 saccular and 3 fusiform, 4 located at the middle tract of the splenic artery, 5 at the distal tract and 2 intra-parenchymal. The diagnosis was performed with colour-Doppler ultrasound and/or CT-angiography; 7 patients were symptomless, 1 had left hypochondriac pain, and 1 had acute abdomen caused by a ruptured SAA. Four SAAs were treated by micro coil embolisation of the aneurysmal sac with preservation of splenic artery patency; in 2 cases this was associated with transcatheter injection of N-butyl-2-cyanoacrylate. Four cases were treated by endovascular ligature, with sectoral spleen ischaemia. One ruptured SAA received emergency treatment with splenic artery cyanoacrylate embolisation. Two intra-parenchymal SAAs were excluded, one by cyanoacrylate embolisation of the afferent artery and the other by transcatheter thrombin injection in the aneurysmal sac. Results. Technical success was observed in all cases (in 10/11 at the end of the procedure; in 1/11 at CT performed 3 days after the procedure). The follow-up (mean 18 months; range 6-36) was performed by colour-Doppler ultrasound and/or CT-angiography 3, 6 and 12 months after the procedure and subsequently once a year; the complete exclusion of the aneurysms was confirmed in 11/11 cases. The complications were: 4 cases of mild pleuritis; fever and left hypochondriac pain 1 day after the procedure (in the same 4 patients and in one other case); 5 cases of sectorial spleen ischaemia and 1 case of diffuse spleen infarction with partial revascularization by collateral vessels. No alteration of the levels of pancreatic enzymes was found; a transitory increase in platelet count occurred only in the patient with diffuse spleen infarction. Conclusions. Using different

  20. Technique, Complication, and Long-Term Outcome for Endovascular Treatment of Iliac Artery Occlusion

    International Nuclear Information System (INIS)

    Ozkan, Ugur; Oguzkurt, Levent; Tercan, Fahri

    2010-01-01

    The aim of this study was to report technical details, procedure-related complications, and results of endovascular treatment in chronic iliac artery occlusion. Between 2001 and 2008, endovascular treatments of 127 chronic iliac artery occlusions in 118 patients (8 women and 110 men; mean age, 59 years) were retrospectively reviewed. The study was based on Ad Hoc Committee on Reporting Standards (Society for Vascular Surgery/International Society for Cardiovascular Surgery Standards). All occlusions were treated with stent placement with or without preliminary balloon angioplasty. Kaplan-Meier estimators were used to determine patency rates. Univariate and multivariate analyses were performed to determine variables affecting successful recanalization, major complications, early stent thrombosis (≤30 days), and primary and secondary patency rates. Initial technical success was achieved in 117 (92%) procedures. Successful recanalization was obtained by antegrade approach in 69 of 77 (90%) procedures and by retrograde approach in 52 of 105 (50%) procedures (p < 0.001). Complications were encountered in 28 (24%) patients [minor in 7 patients (6%) and major in 22 patients (19%)]. One death occurred in the operative period secondary to iliac artery rupture. Early stent thrombosis was seen in eight (7%) patients. Presence of critical limb ischemia (p = 0.03), subintimal recanalization (p = 0.03), and major complication (p = 0.02) were the independent predictors of early stent thrombosis on multivariate analysis. Primary and secondary patency rates at 5 years were 63 and 93%, respectively. Presence of critical limb ischemia, TASC type C iliac lesions, combined occlusions of both common and external iliac arteries, and major complications were associated with decreased patency rates on univariate analysis, whereas these factors were not independent predictors of stent patency on multivariate analysis. In conclusion, endovascular treatment of iliac artery occlusion has a

  1. Effect of low-intensity low-dose rate irradiation on the incidence and the development of spontaneous leukosis in AKR mice

    International Nuclear Information System (INIS)

    Burlakova, E.B.; Erokhin, V.N.

    2001-01-01

    Development of spontaneous leukosis in AKR mice is accelerated by irradiation with low doses of 1.2-2.4 cGy and low dose rate 0.06 cGy/day. The leukoses incidence rate increases. Deaths of the animals from leukosis occurs earlier, shortening the average and maximum life-spans of the animals. The dynamics of changes in the mass of organs of the immune systems (thymus and spleen) shows extrema. The moment of reaching the extremum correlates with the maximum rate of animals' deaths [ru

  2. Complications in Endovascular Neurosurgery: Critical Analysis and Classification.

    Science.gov (United States)

    Ravindra, Vijay M; Mazur, Marcus D; Park, Min S; Kilburg, Craig; Moran, Christopher J; Hardman, Rulon L; Couldwell, William T; Taussky, Philipp

    2016-11-01

    Precisely defining complications, which are used to measure overall quality, is necessary for critical review of delivery of care and quality improvement in endovascular neurosurgery, which lacks common definitions for complications. Furthermore, in endovascular interventions, events that may be labeled complications may not always negatively affect outcome. Our objective is to provide precise definitions for quality evaluation within endovascular neurosurgery. Thus, we propose an endovascular-specific classification system of complications based on our own patient series. This single-center review included all patients who had endovascular interventions from September 2013 to August 2015. Complication types were analyzed, and a descriptive analysis was undertaken to calculate the incidence of complications overall and in each category. Two hundred and seventy-five endovascular interventions were performed in 245 patients (65% female; mean age, 55 years). Forty complications occurred in 39 patients (15%), most commonly during treatment of intracranial aneurysms (24/40). Mechanical complications (eg, device deployment, catheter, or closure device failure) occurred in 8/40, technical complications (eg, failure to deploy flow diverter, unintended embolization, air emboli, retroperitoneal hemorrhage, dissection) in 11/40, judgment errors (eg, patient or equipment selection) in 9/40, and critical events (eg, groin hematoma, hemorrhagic or thromboembolic complications) in 12/40 patients. Only 12/40 complications (30%) resulted in new neurologic deficits, vessel injury requiring surgery, or blood transfusion. We propose an endovascular-specific classification system of complications with 4 categories: mechanical, technical, judgment errors, and critical events. This system provides a framework for future studies and quality control in endovascular neurosurgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Early endovascular treatment of superior mesenteric occlusion secondary to thromboemboli.

    Science.gov (United States)

    Jia, Z; Jiang, G; Tian, F; Zhao, J; Li, S; Wang, K; Wang, Y; Jiang, L; Wang, W

    2014-02-01

    To evaluate our early experience with endovascular revascularization in patients with acute thromboembolic occlusion of the superior mesenteric artery (SMA). A retrospective review was conducted of all patients who underwent endovascular revascularization for acute thromboembolic SMA occlusion from May 2005 to May 2012. Endovascular revascularization was performed using aspiration, intra-arterial thrombolysis, and adjunctive stent-placement techniques. Laparotomy was performed if the patient developed clinical signs of advanced bowel ischemia after endovascular procedure. Twenty-one patients underwent endovascular revascularization for acute thromboembolic SMA occlusion. All presented with acute-onset abdominal pain. Three patients had rebound tenderness before the procedure. Computed tomography angiography revealed complete occlusion in seven cases and incomplete occlusion in 14 cases, with no evidence of free gas or bowel necrosis. The median duration from onset of symptoms to revascularization was 8.7 ± 4.1 hours (range, 2-18 hours). Completely successful endovascular revascularization occurred in six cases (aspiration alone, 3 cases; combined aspiration and urokinase, 3 cases); partial success was achieved in 15 cases (aspiration alone, 4 cases; combined aspiration and urokinase, 10 cases; and combined aspiration, urokinase, and stent placement, 1 case). Laparotomy was required in five patients, all of whom had SMA main trunk complete occlusion and required small bowel resection. The 30-day mortality for all patients was 9.5%. During a median follow-up of 26 months, 15 patients remained asymptomatic, three patients reported occasional abdominal pain, and one patient had temporary short-bowel syndrome. Percutaneous revascularization is a promising alternative to surgery for acute SMA occlusion in selected patients who have no signs of advanced bowel ischemia. Early diagnosis followed by prompt endovascular intervention with close postprocedural monitoring is

  4. Acute Iliac Artery Rupture: Endovascular Treatment

    International Nuclear Information System (INIS)

    Chatziioannou, A.; Mourikis, D.; Katsimilis, J.; Skiadas, V.; Koutoulidis, V.; Katsenis, K.; Vlahos, L.

    2007-01-01

    The authors present 7 patients who suffered iliac artery rupture over a 2 year period. In 5 patients, the rupture was iatrogenic: 4 cases were secondary to balloon angioplasty for iliac artery stenosis and 1 occurred during coronary angioplasty. In the last 2 patients, the rupture was secondary to iliac artery mycotic aneurysm. Direct placement of a stent-graft was performed in all cases, which was dilated until extravasation was controlled. Placement of the stent-graft was successful in all the cases, without any complications. The techniques used, results, and mid-term follow-up are presented. In conclusion, endovascular placement of a stent-graft is a quick, minimally invasive, efficient, and safe method for emergency treatment of acute iliac artery rupture, with satisfactory short- and mid-term results

  5. Endovascular image-guided interventions (EIGIs)

    International Nuclear Information System (INIS)

    Rudin, Stephen; Bednarek, Daniel R.; Hoffmann, Kenneth R.

    2008-01-01

    Minimally invasive interventions are rapidly replacing invasive surgical procedures for the most prevalent human disease conditions. X-ray image-guided interventions carried out using the insertion and navigation of catheters through the vasculature are increasing in number and sophistication. In this article, we offer our vision for the future of this dynamic field of endovascular image-guided interventions in the form of predictions about (1) improvements in high-resolution detectors for more accurate guidance, (2) the implementation of high-resolution region of interest computed tomography for evaluation and planning, (3) the implementation of dose tracking systems to control patient radiation risk, (4) the development of increasingly sophisticated interventional devices, (5) the use of quantitative treatment planning with patient-specific computer fluid dynamic simulations, and (6) the new expanding role of the medical physicist. We discuss how we envision our predictions will come to fruition and result in the universal goal of improved patient care.

  6. Endovascular Treatment of an Aortoiliac Tuberculous Pseudoaneurysm

    International Nuclear Information System (INIS)

    Villegas, Miguel O.; Mereles, Alberto Pérez; Tamashiro, Gustavo A.; Dini, Andrés E.; Mollón, Ana P.; De Cándido, Laura V.; Zelaya, Denis A.; Soledispa-Suarez, Carlos I.; Denato, Sergio; Tamashiro, Alberto; Diaz, Jose A.

    2013-01-01

    We report a rare case of a tuberculous mycotic aortoiliac pseudoaneurysm treated with an endovascular procedure and follow-up of 36 months. The patient was a white 72-year-old man with pulmonary tuberculosis and a former smoker with hypertension, chronic renal failure, and dyslipidemia. A computed tomographic scan of the abdomen and pelvis revealed a left paravertebral cavity with fluid content and involvement of vertebrae L2–L4. After a surgical repair attempt, the patient was treated with the implant of a bifurcated endoprosthesis. Because it is unlikely that any center has extensive experience in the management of this rare manifestation of the disease, we reviewed the literature for similar cases.

  7. Endovascular Treatment of an Aortoiliac Tuberculous Pseudoaneurysm

    Energy Technology Data Exchange (ETDEWEB)

    Villegas, Miguel O.; Mereles, Alberto Perez; Tamashiro, Gustavo A.; Dini, Andres E.; Mollon, Ana P.; De Candido, Laura V.; Zelaya, Denis A.; Soledispa-Suarez, Carlos I.; Denato, Sergio; Tamashiro, Alberto; Diaz, Jose A., E-mail: joseantoniodiaz@hotmail.com [Hospital Nacional Prof. Alejandro Posadas, Department of Cardiology, Section of Hemodinamia (Argentina)

    2013-04-15

    We report a rare case of a tuberculous mycotic aortoiliac pseudoaneurysm treated with an endovascular procedure and follow-up of 36 months. The patient was a white 72-year-old man with pulmonary tuberculosis and a former smoker with hypertension, chronic renal failure, and dyslipidemia. A computed tomographic scan of the abdomen and pelvis revealed a left paravertebral cavity with fluid content and involvement of vertebrae L2-L4. After a surgical repair attempt, the patient was treated with the implant of a bifurcated endoprosthesis. Because it is unlikely that any center has extensive experience in the management of this rare manifestation of the disease, we reviewed the literature for similar cases.

  8. Effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors in murine bone marrow cells

    Energy Technology Data Exchange (ETDEWEB)

    Saitou, Mikio; Sirata, Katsutoshi; Yanai, Takanori; Tanaka, Satoshi; Onodera, Junichi; Otsu, Hiroshi; Sato, Fumiaki [Institute for Environmental Sciences, Department of Radiobiology, Rokkasho, Aomori (Japan)

    1999-07-01

    To evaluate effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors of cells, the dose dependency of the expression of cytokines, interleukin-6 (IL-6) and granulocyte-macrophage colony stimulating factor (GM-CSF), of mice is being measured at accumulated doses between 1 and 8 Gy, with the dose interval of 1 Gy. In the present work, specific-pathogen-free (SPF) C3H-HeN female mice were irradiated by {sup 137}Cs {gamma}-rays with the doses of 5-8 Gy at the dose rate of 20 mGy (22 h-day){sup -1}, and the expression of IL-6 and GM-CSF in bone marrow and spleen cells from the mice were measured semiquantitatively by the reverse transcriptase-polymerase chain reaction (RT-PCR) method. (author)

  9. Effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors in murine bone marrow cells

    Energy Technology Data Exchange (ETDEWEB)

    Saitou, Mikio; Yamada, Yutaka; Shirata, Katsutoshi; Yanai, Takanori; Izumi, Jun; Tanaka, Satoshi; Onodera, Jun' ichi; Otsu, Hiroshi; Sato, Fumiaki [Institute for Environmental Sciences, Rokkasho, Aomori (Japan)

    2000-07-01

    To evaluate effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors of cells, the expression of cytokines, interleukin-6 (IL-6) and granulocyte-macrophage colony stimulating factor (GM-CSF), of mice is being measured at accumulated doses between 1 and 8 Gy, with the dose interval of 1 Gy. In the present work, ten specific-pathogen-free (SPF) C3H/HeN female mice per experimental group were irradiated with {sup 137}Cs {gamma}-rays with the doses of 1-4 Gy at the dose rate of 20 mGy/(22 h-day), and the expression of IL-6 and GM-CSF in bone marrow and spleen cells from the mice was measured semiquantitatively by the reverse transcriptase-polymerase chain reaction (RT-PCR) method. (author)

  10. Effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors in murine bone marrow cells

    International Nuclear Information System (INIS)

    Saitou, Mikio; Yamada, Yutaka; Shirata, Katsutoshi; Yanai, Takanori; Izumi, Jun; Tanaka, Satoshi; Onodera, Jun'ichi; Otsu, Hiroshi; Sato, Fumiaki

    2000-01-01

    To evaluate effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors of cells, the expression of cytokines, interleukin-6 (IL-6) and granulocyte-macrophage colony stimulating factor (GM-CSF), of mice is being measured at accumulated doses between 1 and 8 Gy, with the dose interval of 1 Gy. In the present work, ten specific-pathogen-free (SPF) C3H/HeN female mice per experimental group were irradiated with 137 Cs γ-rays with the doses of 1-4 Gy at the dose rate of 20 mGy/(22 h-day), and the expression of IL-6 and GM-CSF in bone marrow and spleen cells from the mice was measured semiquantitatively by the reverse transcriptase-polymerase chain reaction (RT-PCR) method. (author)

  11. Anesthesia Approach in Endovascular Aortic Reconstruction

    Directory of Open Access Journals (Sweden)

    Ayşin Alagöl

    2013-03-01

    Full Text Available Introduction: We have analyzed our initial results of our anesthesia techniques in our new-onset endovascular aortic reconstruction cases.Patients and Methods: The perioperative data of 15 elective and emergent endovascular aortic reconstruction cases that were operated in 2010-2011 were collected in a database. The choice of anesthesia was made by the risk factors, surgical team’s preferences, type and location of the aortic pathology and by the predicted operation duration. The data of local and general anesthesia cases were compared.Results: Thirteen (86.7% cases were male and 2 (13.3% female. Eleven patients were in ASA Class III. The demographic parameters, ASA classifications, concurrent diseases were similar in both groups. Thirteen (86.7% cases had infrarenal abdominal aortic aneurysm and 2 (13.3% had Type III aortic dissection. The diastolic arterial pressures were lower in general anesthesia group in 20th and 40th minutes’ measurements just like the mean arterial pressure measurements at the 40th, 100th minutes and during the deployment of the graft. Postoperative mortality occurred in 3 (20.0% patients and they all had general anesthesia and they were operated on emergency basis. Postoperative morbidity occurred in four patients that had general anesthesia (acute renal failure, multi-organ failure and pneumonia. The other patient had atrial fibrillation on the 1st postoperative day and was converted to sinus rhythm with amiodarone infusion.Conclusion: Edovascular aortic reconstruction procedures can safely be performed with both general and local anesthesia less invasively compared to open surgery. General anesthesia may be preferred for the better hemodynamic control.

  12. SU-E-T-501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study

    Energy Technology Data Exchange (ETDEWEB)

    Cvetkovic, D; Zhang, P; Wang, B; Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2014-06-01

    Purpose: Pulsed low dose rate radiotherapy (PLDR) is a re-irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials and Methods: Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non-irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin-fixed, paraffin-embedded and stained with H and E. Morphological changes were observed under a microscope. Results: Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group. Conclusions: Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.

  13. Freshly induced short-lived gamma-ray activity as a measure of fission rates in lightly re-irradiated spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kroehnert, H., E-mail: hanna.kroehnert@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Perret, G., E-mail: gregory.perret@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Murphy, M.F., E-mail: mike.murphy@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Chawla, R., E-mail: rakesh.chawla@epfl.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2010-12-01

    A new measurement technique has been developed to determine fission rates in burnt fuel, following re-irradiation in a zero-power research reactor. The development has been made in the frame of the LIFE-PROTEUS program at the Paul Scherrer Institute, which aims at characterizing the interfaces between fresh and highly burnt fuel assemblies in modern LWRs. To discriminate against the high intrinsic gamma-ray activity of the burnt fuel, the proposed measurement technique uses high-energy gamma-rays, above 2000 keV, emitted by short-lived fission products freshly produced in the fuel. To demonstrate the feasibility of this technique, a fresh UO{sub 2} sample and a 36 GWd/t burnt UO{sub 2} sample were irradiated in the PROTEUS reactor and their gamma-ray activities were recorded directly after irradiation. For both fresh and the burnt fuel samples, relative fission rates were derived for different core positions, based on the short-lived {sup 142}La (2542 keV), {sup 89}Rb (2570 keV), {sup 138}Cs (2640 keV) and {sup 95}Y (3576 keV) gamma-ray lines. Uncertainties on the inter-position fission rate ratios were mainly due to the uncertainties on the net-area of the gamma-ray peaks and were about 1-3% for the fresh sample, and 3-6% for the burnt one. Thus, for the first time, it has been shown that the short-lived gamma-ray activity, induced in burnt fuel by irradiation in a zero-power reactor, can be used as a quantitative measure of the fission rate. For both fresh and burnt fuel, the measured results agreed, within the uncertainties, with Monte Carlo (MCNPX) predictions.

  14. Utilization of freshly induced high-energy gamma-ray activity as a measure of fission rates in re-irradiated burnt UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, M. F.; Perret, G. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); Krohnert, H.; Chawla, R. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2009-07-01

    In the frame of the LIFE-PROTEUS (Large-scale Irradiation Fuel Experiments at PROTEUS) program, a measurement technique is being developed to measure fission rates in burnt fuel, following re-irradiation in a zero-power research reactor. In the presented approach, the fission rates are estimated by measuring high energy gamma-rays (above 2000 keV) emitted by short-lived fission products freshly produced in the fuel. Due to their high energies, these gamma-rays can be discriminated against the high intrinsic gamma-ray activity of the burnt fuel, which reaches energies up to 2000 keV. To demonstrate the feasibility of this approach, fresh and burnt fuel samples (with burn-ups varying from 36 to 64 MWd/kg) were irradiated in the PROTEUS reactor at the Paul Scherrer Institut, and their emitted gamma-ray spectra were recorded shortly after irradiation. It was possible, for the first time, to detect the short-lived gamma-ray activity in the high-energy region, even in the presence of the intrinsic gamma-ray background of the burnt fuel samples. Using the short-lived gamma-ray lines {sup 142}La (2542 keV), {sup 89}Rb (2570 keV), 95Y (2632 keV), {sup 138}Cs (2640 keV) and {sup 95}Y (3576 keV), relative fission rates between different core positions were derived for a fresh sample as well as for a burnt sample with a burn-up of 36 MWd/kg. It was shown that, for both the fresh and burnt fuel samples, the measured fission rate ratios agreed well, i.e. within the statistical uncertainties, with calculation results obtained by Monte Carlo simulations. (authors)

  15. Investigation of Interfraction Variations of MammoSite Balloon Applicator in High-Dose-Rate Brachytherapy of Partial Breast Irradiation

    International Nuclear Information System (INIS)

    Kim, Yongbok; Johnson, Mark M.S.; Trombetta, Mark G.; Parda, David S.; Miften, Moyed

    2008-01-01

    Purpose: To measure the interfraction changes of the MammoSite applicator and evaluate their dosimetric effect on target coverage and sparing of organs at risk. Methods and Materials: A retrospective evaluation of the data from 19 patients who received 10 fractions (34 Gy) of high-dose-rate partial breast irradiation was performed. A computed tomography-based treatment plan was generated for Fraction 1, and a computed tomography scan was acquired just before the delivery of each fraction to ensure a consistent shape of the balloon. The eccentricity, asymmetry, and planning target volume (PTV) for plan evaluation purposes (PTV E VAL), as well as trapped air gaps, were measured for all patients. Furthermore, 169 computed tomography-based treatment plans were retrospectively generated for Fractions 2-10. Interfraction dosimetric variations were evaluated using the %PTV E VAL coverage, target dose homogeneity index, target dose conformal index, and maximum doses to the organs at risks. Results: The average variation of eccentricity and asymmetry from Fraction 1 values of 3.5% and 1.1 mm was -0.4% ± 1.6% and -0.1 ± 0.6 mm. The average trapped air gap volume was dramatically reduced from before treatment (3.7 cm 3 ) to Fraction 1 (0.8 cm 3 ). The PTV E VAL volume change was insignificant. The average variation for the %PTV E VAL, target dose homogeneity, and target dose conformal index from Fraction 1 values of 94.7%, 0.64, and 0.85 was 0.15% ± 2.4%, -0.35 ± 2.4%, and -0.34 ± 4.9%, respectively. The average Fraction 1 maximum skin and ipsilateral lung dose of 3.2 Gy and 2.0 Gy varied by 0.08 ± 0.47 and -0.16 ± 0.29 Gy, respectively. Conclusion: The interfraction variations were patient specific and fraction dependent. Although the average interfraction dose variations for the target and organs at risk were not clinically significant, the maximum variations could be clinically significant

  16. Stimulating action of continuous γ-irradiation with low dose-rates on the growth and development of Aspergillus niger

    International Nuclear Information System (INIS)

    Kuzin, A.M.; Nikitina, A.N.; Yurov, S.S.; Primak, V.N.

    1976-01-01

    Continuous γ-irradiation (1.6 - 4.1 rad/hr) of Aspergillus niger cultured in a mineral medium has been shown to stimulate markedly the growth of the culture and the production of organic acids. Optimum conditions for the stimulating effect have been found

  17. Endovascular recanalization of native chronic total occlusions in patients with failed lower-extremity bypass grafts.

    Science.gov (United States)

    Wrigley, Clinton W; Vance, Ansar; Niesen, Timothy; Grilli, Christopher; Velez, J Daniel; Agriantonis, Demetrios J; Kimbiris, George; Garcia, Mark J; Leung, Daniel A

    2014-09-01

    To investigate the feasibility, safety, and outcome of endovascular recanalization of native chronic total occlusions (CTOs) in patients with failed lower-extremity bypass grafts. Retrospective review of 19 limbs in 18 patients with failed lower-extremity bypass grafts that underwent recanalization of native arterial occlusions between February 2009 and April 2013 was performed. Nine of the limbs presented with acute ischemia and 10 presented with chronic ischemia, including eight with critical limb ischemia and two with disabling claudication. The mean patency of the failed bypass grafts (63% venous) was 27 months. All limbs had Transatlantic Inter-Society Consensus class D lesions involving the native circulation. Technical success of the endovascular recanalization procedure was achieved in all but one limb (95%). The mean ankle brachial indices before and after treatment were 0.34 and 0.73, respectively. There were no major complications or emergency amputations. Mean patient follow-up was 64 weeks, and two patients were lost to follow-up. Primary patency rates at 3, 6, and 12 months were 87%, 48%, and 16%, respectively. Successful secondary procedures were performed in seven patients, with secondary patency rates at 3, 6, and 12 months of 88%, 73%, and 44%, respectively. Limb salvage rates at 12 and 24 months were 94% and 65%, and amputation-free survival rates at 12 and 24 months were 87% and 60%, respectively. Endovascular recanalization of native CTOs in patients with failed lower-extremity bypass grafts is technically feasible and safe and results in acceptable limb salvage. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  18. Endovascular recanalization of acute intracranial vertebrobasilar artery occlusion using local fibrinolysis and additional balloon angioplasty

    International Nuclear Information System (INIS)

    Kashiwagi, Junji; Okahara, Mika; Kiyosue, Hiro; Tanoue, Shuichi; Sagara, Yoshiko; Mori, Hiromu; Hori, Yuzo; Abe, Toshi

    2010-01-01

    Vertebrobasilar artery occlusion (VBO) produces high mortality and morbidity due to low recanalization rate utilization in endovascular therapy. The use of percutaneous transluminal angioplasty (PTA) to improve recanalization rate additional to local intra-arterial fibrinolysis (LIF) was investigated in this study. Results obtained following recanalization therapy in acute intracranial VBO are reported. Eighteen consecutive patients with acute VBO underwent LIF with or without PTA, from August 2000 to May 2006. Eight patients were treated using LIF alone, and ten required additional PTA. Rate of recanalization, neurological status before treatment, and clinical outcomes were evaluated. Of 18 patients, 17 achieved recanalization. One procedure-related complication of subarachnoid hemorrhage occurred. Overall survival rate was 94.4% at discharge. Seven patients achieved good outcomes [modified Rankin scale (mRS) 0-2], and the other 11 had poor outcomes (mRS 3-6). Five of six patients who scored 9-14 on the Glasgow Coma Scale (GCS) before treatment displayed good outcomes, whereas ten of 12 patients who scored 3-8 on the GCS showed poor outcomes. GCS prior to treatment showed a statistically significant correlation to outcomes (p < 0.05). Moreover, the National Institutes of Health Stroke Scale (NIHSS) before treatment correlated well with mRS (correlation coefficient 0.487). No statistical difference between the good and poor outcome groups was observed for the duration of symptoms, age, etiology, and occlusion site. Endovascular recanalization can reduce mortality and morbidity of acute VBO. Good GCS and NIHSS scores prior to treatment can predict the efficacy of endovascular recanalization. (orig.)

  19. Outcomes of infrageniculate retrograde versus transfemoral access for endovascular intervention for chronic lower extremity ischemia.

    Science.gov (United States)

    Taha, Ashraf G; Abou Ali, Adham N; Al-Khoury, George; Singh, Michael J; Makaroun, Michel S; Avgerinos, Efthymios D; Chaer, Rabih A

    2018-03-31

    Retrograde infrageniculate access is an alternative treatment strategy for patients who have failed to respond to antegrade endovascular intervention. This study compares the outcomes of infrageniculate retrograde arterial access with the conventional transfemoral access for the endovascular management of chronic lower extremity ischemia. This was a retrospective single-center review of retrograde endovascular intervention (REI) from 2012 to 2016. Indications for intervention, comorbidities, complications, procedural success, limb outcomes, and mortality were analyzed. Technical failure was defined as the inability to complete the procedure because of failed access or unsuccessful recanalization. Infrageniculate access and transfemoral access were obtained with ultrasound or angiographic roadmap guidance. Patency rates were calculated for technically successful interventions. There were 47 patients (85% presenting with critical limb ischemia) who underwent sheathless REI after failed antegrade recanalization of TransAtlantic Inter-Society Consensus class D infrainguinal lesions, whereas 93 patients (83% with critical limb ischemia) underwent standard transfemoral access. There were 16 (34%) femoropopliteal, 14 (30%) tibial, and 17 (36%) multilevel interventions in the retrograde group compared with 41 (41%) femoropopliteal, 20 (20%) tibial, and 39 (39%) multilevel interventions in the transfemoral group. Access sites for the retrograde group included the dorsalis pedis (26%), midcalf peroneal (24%), anterior tibial (22%), posterior tibial (26%), and popliteal (2%) arteries. Overall technical success was achieved in 57% of the retrograde group compared with 78% of the transfemoral group. Mean follow-up was 20 months (range, 1-45 months). There were no significant differences in the primary patency rates between the two groups at 1 year and 2 years. The primary assisted patency rates were significantly better in the transfemoral group at 1 year (66% vs 46%; P

  20. Endovascular Management of Patients with Head and Neck Cancers Presenting with Acute Hemorrhage: A Single-Center Retrospective Study

    Energy Technology Data Exchange (ETDEWEB)

    Vilas Boas, P. P.; Castro-Afonso, L. H. de; Monsignore, L. M.; Nakiri, G. S. [University of São Paulo, Division of Interventional Neuroradiology, Ribeirão Preto Medical School (Brazil); Mello-Filho, F. V. de [University of São Paulo, Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School (Brazil); Abud, D. G., E-mail: dgabud@fmrp.usp.br [University of São Paulo, Division of Interventional Neuroradiology, Ribeirão Preto Medical School (Brazil)

    2017-04-15

    PurposeAcute hemorrhage associated with cancers of the head and neck is a life-threatening condition that requires immediate action. The aim of this study was to assess the safety and efficacy of endovascular embolization for acute hemorrhage in patients with head and neck cancers.Materials and MethodsData were retrospectively collected from patients with head and neck cancers who underwent endovascular embolization to treat acute hemorrhage. The primary endpoint was the rate of immediate control of hemorrhage during the first 24 h after embolization. The secondary endpoints were technical or clinical complications, rate of re-hemorrhage 24 h after the procedure, time from embolization to re-hemorrhage, hospitalization time, mortality rate, and time from embolization to death.ResultsFifty-one patients underwent endovascular embolization. The primary endpoint was achieved in 94% of patients. The rate of technical complications was 5.8%, and no clinical complication was observed. Twelve patients (23.5%) had hemorrhage recurrence after an average time of 127.5 days. The average hospitalization time was 7.4 days, the mortality rate during the follow-up period was 66.6%, and the average time from embolization to death was 132.5 days.ConclusionEndovascular embolization to treat acute hemorrhage in patients with head and neck cancers is a safe and effective method for the immediate control of hemorrhage and results in a high rate of hemorrhage control. Larger studies are necessary to determine which treatment strategy is best for improving patient outcomes.

  1. Endovascular Management of Patients with Head and Neck Cancers Presenting with Acute Hemorrhage: A Single-Center Retrospective Study

    International Nuclear Information System (INIS)

    Vilas Boas, P. P.; Castro-Afonso, L. H. de; Monsignore, L. M.; Nakiri, G. S.; Mello-Filho, F. V. de; Abud, D. G.

    2017-01-01

    PurposeAcute hemorrhage associated with cancers of the head and neck is a life-threatening condition that requires immediate action. The aim of this study was to assess the safety and efficacy of endovascular embolization for acute hemorrhage in patients with head and neck cancers.Materials and MethodsData were retrospectively collected from patients with head and neck cancers who underwent endovascular embolization to treat acute hemorrhage. The primary endpoint was the rate of immediate control of hemorrhage during the first 24 h after embolization. The secondary endpoints were technical or clinical complications, rate of re-hemorrhage 24 h after the procedure, time from embolization to re-hemorrhage, hospitalization time, mortality rate, and time from embolization to death.ResultsFifty-one patients underwent endovascular embolization. The primary endpoint was achieved in 94% of patients. The rate of technical complications was 5.8%, and no clinical complication was observed. Twelve patients (23.5%) had hemorrhage recurrence after an average time of 127.5 days. The average hospitalization time was 7.4 days, the mortality rate during the follow-up period was 66.6%, and the average time from embolization to death was 132.5 days.ConclusionEndovascular embolization to treat acute hemorrhage in patients with head and neck cancers is a safe and effective method for the immediate control of hemorrhage and results in a high rate of hemorrhage control. Larger studies are necessary to determine which treatment strategy is best for improving patient outcomes.

  2. Percutaneous endovascular aneurysm repair in morbidly obese patients.

    Science.gov (United States)

    Chin, Jason A; Skrip, Laura; Sumpio, Bauer E; Cardella, Jonathan A; Indes, Jeffrey E; Sarac, Timur P; Dardik, Alan; Ochoa Chaar, Cassius I

    2017-03-01

    Endovascular aneurysm repair (EVAR) with percutaneous femoral access (PEVAR) has several potential advantages. Morbidly obese (MO) patients present unique anatomical challenges and have not been specifically studied. This study examines the trends in the use of PEVAR and its surgical outcomes compared with open femoral cutdown (CEVAR) in MO patients. The American College of Surgeons National Surgical Quality Improvement Program files for the years 2005 to 2013 were reviewed. The study included all MO patients (body mass index [BMI] ≥40 kg/m 2 ) undergoing EVAR. Patients were categorized as having CEVAR if they had any one of 11 selected Current Procedural Terminology (American Medical Association, Chicago, Ill) codes describing an open femoral procedure. The PEVAR group included any remaining patients who had only codes for EVAR and endovascular procedures. Linear correlation was used to evaluate temporal trends in the use of PEVAR among MO patients. Baseline comorbidities and surgical outcomes were compared between the PEVAR and CEVAR groups using χ 2 tests or t-tests. There were 833 MO patients (470 CEVAR and 363 PEVAR) constituting 3.0% of all patients undergoing EVAR. The use of PEVAR in MO patients significantly increased from 27.3% of total EVARs in the years 2005 to 2006 to 48.6% in 2013 (P = .039). The two groups had similar baseline characteristics, including age, BMI, comorbidities, and emergency procedures, except for history of severe chronic obstructive pulmonary disease (29.6% CEVAR vs 22.6% PEVAR; P = .024). PEVAR patients had shorter duration of anesthesia (244 vs 260 minutes; P = .048) and shorter total operation time (158 vs 174 minutes; P = .002). PEVAR patients had significantly decreased wound complications (5.5% vs 9.4%; P = .039). There was a trend towards PEVAR patients being more likely to be discharged home than to a facility (93.6% vs 87.8%; P = .060). There was no difference in any other complication or mortality. A subgroup

  3. Increased mortality by septicemia, interstitial pneumonitis and pulmonary fibrosis among bone marrow transplant recipients receiving an increased mean dose rate of total irradiation

    International Nuclear Information System (INIS)

    Ringden, O.; Baaryd, I.; Johansson, B.

    1983-01-01

    Seven bone marrow transplant recipients with acute lymphoblastic leukemia receiving a mean dose rate of 0.07 Gy/min of total body irradiation towards the pelvic midpoint and the lungs had an increased (p<0.01) overall death rate of 86 per cent compared with 33 per cent among 27 patients with acute non-lymphoblastic leukemia or acute lymphoblastic leukemia treated with a mean dose rate of 0.04 Gy/min. Among the patients receiving the higher dose rate there was an increased mortality in causes related to radiation toxicity like early septicemia, interstitial pneumonitis and pulmonary fibrosis, compared with all patients receiving the lower dose rate (p<0.01) and also with 10 patients from this group with acute lymphoblastic leukemia (p<0.02). (Auth.)

  4. Early experience with transfemoral endovascular aneurysm management (TEAM) in the treatment of aortic aneurysms

    NARCIS (Netherlands)

    Balm, R.; Eikelboom, B. C.; May, J.; Bell, P. R.; Swedenborg, J.; Collin, J.

    1996-01-01

    OBJECTIVES: To evaluate the early experience with transfemoral endovascular aortic aneurysm management using the Endovascular Grafting System. DESIGN: Multi-centre prospective evaluation of the implantation procedure and early results (median follow-up 153 days). SETTING: Department of Surgery,

  5. Fatal late multiple emboli after endovascular treatment of abdominal aortic aneurysm. Case report

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Sandermann, Jes; Bruun-Petersen, J

    1998-01-01

    The short term experience of endovascular treatment of abdominal aortic aneurysms (AAA) seems promising but long term randomised data are lacking. Consequently, cases treated by endovascular procedures need to be closely followed for potential risks and benefits....

  6. Conditioned instrumental behaviour in the rat: Effects of prenatal irradiation with various low dose-rate doses. Instrumentelle Verhaltensuntersuchungen an der Ratte: Ueber die Wirkung verschiedener Dosen einer praenatalen Bestrahlung niedriger Dosisleistung

    Energy Technology Data Exchange (ETDEWEB)

    Klug, H.

    1986-01-01

    4 groups of rats of the Wistar-strain were subjected to ..gamma..-irradiation on the 16th day of gestation. 5 rats received 0,6 Gy low dose rate irradiation, 5 animals received 0,9 Gy low dose and 6 high dose irradiation, 3 females were shamirradiated. The male offspring of these 3 irradiation groups and 1 control group were tested for locomotor coordination on parallel bars and in a water maze. The female offspring were used in an operant conditioning test. The locomotor test showed slight impairment of locomotor coordination in those animals irradiated with 0,9 Gy high dose rate. Swimming ability was significantly impaired by irradiation with 0,9 Gy high dose rate. Performance in the operant conditioning task was improved by irradiation with 0,9 Gy both low and high dose rate. The 0,9 Gy high dose rate group learned faster than all the other groups. For the dose of 0,9 Gy a significant dose rate effect could be observed. For the dose of 0,6 Gy a similar tendency was observed, differences between 0,6 Gy high and low dose rate and controls not being significant.

  7. The effect of endograft device on patient outcomes in endovascular repair of ruptured abdominal aortic aneurysms.

    Science.gov (United States)

    Kansal, Vinay; Nagpal, Sudhir; Jetty, Prasad

    2017-12-01

    Objective Endovascular aneurysm repair for ruptured abdominal aortic aneurysm is being increasingly applied as the intervention of choice. The purpose of this study was to determine whether survival and reintervention rates after ruptured abdominal aortic aneurysm vary between endograft devices. Methods This cohort study identified all ruptured abdominal aortic aneurysms performed at The Ottawa Hospital from January 1999 to May 2015. Data collected included patient demographics, stability index at presentation, adherence to device instructions for use, endoleaks, reinterventions, and mortality. Kruskal-Wallis test was used to compare outcomes between groups. Mortality outcomes were assessed using Kaplan-Meier survival analysis, and multivariate Cox regression modeling. Results One thousand sixty endovascular aneurysm repairs were performed using nine unique devices. Ninety-six ruptured abdominal aortic aneurysms were performed using three devices: Cook Zenith ( n = 46), Medtronic Endurant ( n = 33), and Medtronic Talent ( n = 17). The percent of patients presented in unstable or extremis condition was 30.2, which did not differ between devices. Overall 30-day mortality was 18.8%, and was not statistically different between devices ( p = 0.16), although Medtronic Talent had markedly higher mortality (35.3%) than Cook Zenith (15.2%) and Medtronic Endurant (15.2%). AUI configuration was associated with increased 30-day mortality (33.3% vs. 12.1%, p = 0.02). Long-term mortality and graft-related reintervention rates at 30 days and 5 years were similar between devices. Instructions for use adherence was similar across devices, but differed between the ruptured abdominal aortic aneurysm and elective endovascular aneurysm repair cohorts (47.7% vs. 79.0%, p 30 days post-endovascular aneurysm repair ( p = 0.01). Type 1 endoleak rates differed significantly across devices (Cook Zenith 0.0%, Medtronic Endurant 18.2%, Medtronic Talent 17.6%, p = 0

  8. Endovascular treatment of head and neck arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Dmytriw, A.A. [University Health Network, Joint Department of Medical Imaging, Toronto, Ontario (Canada); Ter Brugge, K.G.; Krings, T.; Agid, R. [Toronto Western Hospital, Division of Neuroradiology, Department of Medical Imaging, Toronto, Ontario (Canada)

    2014-03-15

    Head and neck arteriovenous malformations (H and N AVM) are associated with considerable clinical and psychosocial burden and present a significant treatment challenge. We evaluated the presentation, response to treatment, and outcome of patients with H and N AVMs treated by endovascular means at our institution. Patients with H and N AVMs treated by endovascular means from 1984 to 2012 were evaluated retrospectively. These included AVMs involving the scalp, orbit, maxillofacial, and upper neck localizations. Patient's clinical files, radiological images, catheter angiograms, and surgical reports were reviewed. Eighty-nine patients with H and N AVMs (46 females, 43 males; 48 small, 41 large) received endovascular therapy. The goals of treatment were curative (n = 30), palliative (n = 34), or presurgical (n = 25). The total number of endovascular treatment sessions was 244 (average of 1.5 per patient). The goal of treatment was met in 92.1 % of cases. Eventual cure was achieved in 42 patients accounting for 58.4 % (52/89) of all patients who underwent treatment for any goal. Twenty-eight of these patients were cured by embolization alone (28/89, 31.4 %) of which 18 were single-hole AVFs. Twenty-four were cured by planned surgical excision after presurgical embolization (24/89, 27 %). Seven patients (7/89, 7.2 %) suffered transient and two (2/89, 2.2 %) permanent endovascular treatment complications. Endovascular treatment is effective for H and N AVMs and relatively safe. It is particularly effective for symptom palliation and presurgical aid. Embolization is curative mostly in small lesions and single-hole fistulas. In patients with large non-curable H and N AVMs, endovascular therapy is often the only palliative option. (orig.)

  9. Metallic Zinc Exhibits Optimal Biocompatibility for Bioabsorbable Endovascular Stents

    Science.gov (United States)

    Bowen, Patrick K.; Guillory, Roger J.; Shearier, Emily R.; Seitz, Jan-Marten; Drelich, Jaroslaw; Bocks, Martin; Zhao, Feng; Goldman, Jeremy

    2015-01-01

    Although corrosion resistant bare metal stents are considered generally effective, their permanent presence in a diseased artery is an increasingly recognized limitation due to the potential for long-term complications. We previously reported that metallic zinc exhibited an ideal biocorrosion rate within murine aortas, thus raising the possibility of zinc as a candidate base material for endovascular stenting applications. This study was undertaken to further assess the arterial biocompatibility of metallic zinc. Metallic zinc wires were punctured and advanced into the rat abdominal aorta lumen for up to 6.5 months. This study demonstrated that metallic zinc did not provoke responses that often contribute to restenosis. Low cell densities and neointimal tissue thickness, along with tissue regeneration within the corroding implant, point to optimal biocompatibility of corroding zinc. Furthermore, the lack of progression in neointimal tissue thickness over 6.5 months or the presence of smooth muscle cells near the zinc implant suggest that the products of zinc corrosion may suppress the activities of inflammatory and smooth muscle cells. PMID:26249616

  10. Surgical Clipping versus Endovascular Intervention for the Treatment of Subarachnoid Hemorrhage Patients in New York State.

    Directory of Open Access Journals (Sweden)

    Kimon Bekelis

    Full Text Available Randomized trials have demonstrated a survival benefit for endovascular treatment of ruptured cerebral aneurysms. We investigated the association of surgical clipping and endovascular coiling with outcomes in subarachnoid hemorrhage (SAH patients in a real-world regional cohort.We performed a cohort study involving patients with ruptured cerebral aneurysms, who underwent surgical clipping, or endovascular coiling from 2009-2013 and were registered in the Statewide Planning and Research Cooperative System (SPARCS database. An instrumental variable analysis was used to investigate the association of treatment technique with outcomes.Of the 4,098 patients undergoing treatment, 2,585 (63.1% underwent coiling, and 1,513 (36.9% underwent clipping. Using an instrumental variable analysis, we did not identify a difference in inpatient mortality [marginal effect (ME, -0.56; 95% CI, -1.03 to 0.02], length of stay (LOS (ME, 1.72; 95% CI, -3.39 to 6.84, or the rate of 30-day readmissions (ME, -0.30; 95% CI, -0.82 to 0.22 between the two treatment techniques for patients with SAH. Clipping was associated with a higher rate of discharge to rehabilitation (ME, 0.63; 95% CI, 0.24 to 1.01. In sensitivity analysis, mixed effect regression, and propensity score adjusted regression models demonstrated identical results.Using a comprehensive all-payer cohort of patients in New York State presenting with aneurysmal SAH we did not identify an association of treatment method with mortality, LOS or 30-day readmission. Clipping was associated with a higher rate of discharge to rehabilitation.

  11. Periprocedural and long-term outcomes of endovascular abdominal aortic aneurysm repair in cardiology practice.

    Science.gov (United States)

    Basoor, Abhijeet; Patel, Kiritkumar C; Halabi, Abdul R; Todorov, Mina; Senthilvadivel, Prashanth; Choksi, Nishit; Phan, Thanh; LaLonde, Thomas; Yamasaki, Hiroshi; DeGregorio, Michele

    2014-12-01

    Endovascular repair of abdominal aortic aneurysm (AAA) has recently been made a class I indication in the treatment of AAA. In comparison to the conventional open surgical treatment, endovascular AAA repair (EVAR) is associated with equivalent long-term morbidity and mortality rates. Vascular surgeons perform majority of EVAR. There are no reports for the long-term results of this intervention performed by interventional cardiologists. We present one of the first reports of periprocedural and long-term outcomes of EVAR performed by interventional cardiologists. Retrospective chart review on patients with attempted EVAR between September 2005 and January 2011 was performed. Included cases were all consecutive patients who had attempted EVAR by interventional cardiologists. During the study period EVAR was attempted in 170 patients, with 27% being women. The mean age was 74 years (range 52-93). The endovascular graft placement was successful in 96% (163/170) of patients. Procedure failures were more common in women (6 of 46 vs 1 of 124, P = 0.003). The 30-day mortality was 1.8 % (3 of 170). In patients with successful EVAR the mean follow-up was 30 months and mean length of hospital stay was 3.5 ± 3.2 days. Major periprocedural complications were noted in 9% patients (15 of 167). During follow-up, six patients (3.5%) required re-intervention and additional 16 patients died with no aneurysm related deaths. EVAR primarily performed by interventional cardiologists demonstrates high periprocedural and long-term success rates. A higher EVAR failure rate has been observed in women. © 2014 Wiley Periodicals, Inc.

  12. Percutaneous Endovascular Salvage Techniques for Implanted Venous Access Device Dysfunction

    International Nuclear Information System (INIS)

    Breault, Stéphane; Glauser, Frédéric; Babaker, Malik; Doenz, Francesco; Qanadli, Salah Dine

    2015-01-01

    PurposeImplanted venous access devices (IVADs) are often used in patients who require long-term intravenous drug administration. The most common causes of device dysfunction include occlusion by fibrin sheath and/or catheter adherence to the vessel wall. We present percutaneous endovascular salvage techniques to restore function in occluded catheters. The aim of this study was to evaluate the feasibility, safety, and efficacy of these techniques.Methods and MaterialsThrough a femoral or brachial venous access, a snare is used to remove fibrin sheath around the IVAD catheter tip. If device dysfunction is caused by catheter adherences to the vessel wall, a new “mechanical adhesiolysis” maneuver was performed. IVAD salvage procedures performed between 2005 and 2013 were analyzed. Data included clinical background, catheter tip position, success rate, recurrence, and rate of complication.ResultsEighty-eight salvage procedures were performed in 80 patients, mostly women (52.5 %), with a mean age of 54 years. Only a minority (17.5 %) of evaluated catheters were located at an optimal position (i.e., cavoatrial junction ±1 cm). Mechanical adhesiolysis or other additional maneuvers were used in 21 cases (24 %). Overall technical success rate was 93.2 %. Malposition and/or vessel wall adherences were the main cause of technical failure. No complications were noted.ConclusionThese IVAD salvage techniques are safe and efficient. When a catheter is adherent to the vessel wall, mechanical adhesiolysis maneuvers allow catheter mobilization and a greater success rate with no additional risk. In patients who still require long-term use of their IVAD, these procedures can be performed safely to avoid catheter replacement

  13. Percutaneous Endovascular Salvage Techniques for Implanted Venous Access Device Dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Breault, Stéphane, E-mail: stephane.breault@chuv.ch [Lausanne University Hospital, Diagnostic and Interventional Radiology Department (Switzerland); Glauser, Frédéric, E-mail: frederic.glauser@chuv.ch [Lausanne University Hospital, Angiology and Diagnostic and Interventional Radiology Departments (Switzerland); Babaker, Malik, E-mail: malik.babaker@chuv.ch; Doenz, Francesco, E-mail: francesco.doenz@chuv.ch; Qanadli, Salah Dine, E-mail: salah.qanadli@chuv.ch [Lausanne University Hospital, Diagnostic and Interventional Radiology Department (Switzerland)

    2015-06-15

    PurposeImplanted venous access devices (IVADs) are often used in patients who require long-term intravenous drug administration. The most common causes of device dysfunction include occlusion by fibrin sheath and/or catheter adherence to the vessel wall. We present percutaneous endovascular salvage techniques to restore function in occluded catheters. The aim of this study was to evaluate the feasibility, safety, and efficacy of these techniques.Methods and MaterialsThrough a femoral or brachial venous access, a snare is used to remove fibrin sheath around the IVAD catheter tip. If device dysfunction is caused by catheter adherences to the vessel wall, a new “mechanical adhesiolysis” maneuver was performed. IVAD salvage procedures performed between 2005 and 2013 were analyzed. Data included clinical background, catheter tip position, success rate, recurrence, and rate of complication.ResultsEighty-eight salvage procedures were performed in 80 patients, mostly women (52.5 %), with a mean age of 54 years. Only a minority (17.5 %) of evaluated catheters were located at an optimal position (i.e., cavoatrial junction ±1 cm). Mechanical adhesiolysis or other additional maneuvers were used in 21 cases (24 %). Overall technical success rate was 93.2 %. Malposition and/or vessel wall adherences were the main cause of technical failure. No complications were noted.ConclusionThese IVAD salvage techniques are safe and efficient. When a catheter is adherent to the vessel wall, mechanical adhesiolysis maneuvers allow catheter mobilization and a greater success rate with no additional risk. In patients who still require long-term use of their IVAD, these procedures can be performed safely to avoid catheter replacement.

  14. Measurements of 36Cl production rates from Cl, K, and Ca in concrete at the 500-MeV neutron irradiation facility of KENS

    International Nuclear Information System (INIS)

    Aze, T.; Fujimura, M.; Matsumura, H.; Masumoto, K.; Nakao, N.; Kawai, M.; Matsuzaki, H.; Nagai, H.

    2005-01-01

    In high-energy accelerator facilities, concrete components around beam lines are exposed to