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Sample records for magnetic compression anastomosis

  1. [Application value of magnetic compression anastomosis in digestive tract reconstruction].

    Science.gov (United States)

    Du, Xilin; Fan, Chao; Zhang, Hongke; Lu, Jianguo

    2014-05-01

    Magnetic compression anastomosis can compress tissues together and restore the continuity. Magnetic compression anastomosis mainly experienced three stages: magnetic ring, magnetic ring and column, and smart self-assembling magnets for endoscopy (SAMSEN). Nowadays, the magnetic compression anastomosis has been applied in vascular and different digestive tract surgeries, especially for complex surgery, such as anastomotic stenosis of biliary ducts after liver transplantation or congenital esophageal stenosis. Although only case reports are available at present, the advantages of the magnetic compression anastomosis includes lower cost, simplicity, individualization, good efficacy, safety, and minimally invasiveness. We are building a better technical platform to make magnetic compression anastomosis more advanced and popularized.

  2. MAGNAMOSIS IV: magnetic compression anastomosis for minimally invasive colorectal surgery.

    Science.gov (United States)

    Wall, J; Diana, M; Leroy, J; Deruijter, V; Gonzales, K D; Lindner, V; Harrison, M; Marescaux, J

    2013-08-01

    MAGNAMOSIS forms a compression anastomosis using self-assembling magnetic rings that can be delivered via flexible endoscopy. The system has proven to be effective in full-thickness porcine small-bowel anastomoses. The aim of this study was to show the feasibility of the MAGNAMOSIS system in hybrid endoscopic colorectal surgery and to compare magnetic and conventional stapled anastomoses. A total of 16 swine weighing 35 - 50 kg were used following animal ethical committee approval. The first animal was an acute model to establish the feasibility of the procedure. The subsequent 15 animals were survival models, 10 of which underwent side-to-side anastomoses (SSA) and 5 of which underwent end-to-side (ESA) procedures. Time to patency, surveillance endoscopy, burst pressure, compression force, and histology were assessed. Histology was compared with conventional stapled anastomoses. Magnetic compression forces were measured in various anastomosis configurations. Colorectal anastomoses were performed in all cases using a hybrid NOTES technique. The mean operating time was 71 minutes. Mean time to completion of the anastomosis was similar between the SSA and ESA groups. Burst pressure at 10 days was greater than 95 mmHg in both groups. One complication occurred in the ESA group. Compression force among various configurations of the magnetic rings was significantly different (P < 0.05). Inflammation and fibrosis were similar between magnetic SSA and conventional stapled anastomoses. MAGNAMOSIS was feasible in performing a hybrid NOTES colorectal anastomosis. It has the advantage over circular staplers of precise endoscopic delivery throughout the entire colon. SSA was reliable and effective. A minimum initial compression force of 4 N appears to be required for reliable magnetic anastomoses. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Magnetic compression anastomosis for enteroenterostomy under peritonitis conditions in dogs.

    Science.gov (United States)

    Zhang, Hongke; Tan, Kai; Fan, Chao; Du, Jingwei; Li, Jiangbin; Yang, Tao; Lv, Yi; Du, Xilin

    2017-02-01

    The risk of complications and mortality are high after enteroenterostomy in severe peritonitic conditions. Magnetic compression anastomosis (MCA) is a sutureless technique of high efficacy and safety. The purpose of this study was to compare the efficacy of MCA for enteroenterostomy with stapled and hand-sewn techniques under peritonitic conditions. The peritonitic conditions were created by puncturing the colon with a circular blade in 27 mongrel dogs. Eight hours later, the peritoneal cavity was washed with warm, sterilized normal saline solution. The animals were then randomly divided into three groups and underwent colonic anastomosis with MCA, stapled, or hand-sewn techniques, respectively. Animals were euthanized at 1, 2, and 4 w after the operation; anastomoses were compared on the basis of gross appearance and histology. All magnetic devices formed patent anastomoses without a leak. However, one stapled anastomosis and three hand-sewn anastomoses resulted in leaks. The anastomosis time was significantly less in the MCA group than that of the other two groups (P anastomoses for MCA was smoother than that of the other two groups. MCA is a feasible, safe, and effective alternative for enteroenterostomy under peritonitic conditions in the canine model. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Repair of esophageal atresia with proximal fistula using endoscopic magnetic compression anastomosis (magnamosis) after staged lengthening.

    Science.gov (United States)

    Dorman, Robert M; Vali, Kaveh; Harmon, Carroll M; Zaritzky, Mario; Bass, Kathryn D

    2016-05-01

    We describe the treatment of a patient with long-gap esophageal atresia with an upper pouch fistula, mircogastria and minimal distal esophageal remnant. After 4.5 months of feeding via gastrostomy, a proximal fistula was identified by bronchoscopy and a thoracoscopic modified Foker procedure was performed reducing the gap from approximately 7-5 cm over 2 weeks of traction. A second stage to ligate the fistula and suture approximate the proximal and distal esophagus resulted in a gap of 1.5 cm. IRB and FDA approval was then obtained for endoscopic placement of 10-French catheter mounted magnets in the proximal and distal pouches promoting a magnetic compression anastomosis (magnamosis). Magnetic coupling occurred at 4 days and after magnet removal at 13 days an esophagram demonstrated a 10 French channel without leak. Serial endoscopic balloon dilation has allowed drainage of swallowed secretions as the baby learns bottling behavior at home.

  5. Biliary-duodenal anastomosis using magnetic compression following massive resection of small intestine due to strangulated ileus after living donor liver transplantation: a case report.

    Science.gov (United States)

    Saito, Ryusuke; Tahara, Hiroyuki; Shimizu, Seiichi; Ohira, Masahiro; Ide, Kentaro; Ishiyama, Kohei; Kobayashi, Tsuyoshi; Ohdan, Hideki

    2017-12-01

    Despite the improvements of surgical techniques and postoperative management of patients with liver transplantation, biliary complications are one of the most common and important adverse events. We present a first case of choledochoduodenostomy using magnetic compression following a massive resection of the small intestine due to strangulated ileus after living donor liver transplantation. The 54-year-old female patient had end-stage liver disease, secondary to liver cirrhosis, due to primary sclerosing cholangitis with ulcerative colitis. Five years earlier, she had received living donor liver transplantation using a left lobe graft, with resection of the extrahepatic bile duct and Roux-en-Y anastomosis. The patient experienced sudden onset of intense abdominal pain. An emergency surgery was performed, and the diagnosis was confirmed as strangulated ileus due to twisting of the mesentery. Resection of the massive small intestine, including choledochojejunostomy, was performed. Only 70 cm of the small intestine remained. She was transferred to our hospital with an external drainage tube from the biliary cavity and jejunostomy. We initiated total parenteral nutrition, and percutaneous transhepatic biliary drainage was established to treat the cholangitis. Computed tomography revealed that the biliary duct was close to the duodenum; hence, we planned magnetic compression anastomosis of the biliary duct and the duodenum. The daughter magnet was placed in the biliary drainage tube, and the parent magnet was positioned in the bulbus duodeni using a fiberscope. Anastomosis between the left hepatic duct and the duodenum was accomplished after 25 days, and the biliary drainage stent was placed over the anastomosis to prevent re-stenosis. Contributions to the successful withdrawal of parenteral nutrition were closure of the ileostomy in the adaptive period, preservation of the ileocecal valve, internal drainage of bile, and side-to-side anastomosis

  6. Side-to-side sutureless vascular anastomosis with magnets.

    Science.gov (United States)

    Erdmann, Detlev; Sweis, Ranya; Heitmann, Christoph; Yasui, Koji; Olbrich, Kevin C; Levin, L Scott; Sharkawy, A Adam; Klitzman, Bruce

    2004-09-01

    Abbe and Payr introduced vascular techniques and devices to facilitate vessel anastomosis over a century ago. Obora published the idea of a sutureless vascular anastomosis with use of magnetic rings in 1978. The purpose of this study was to assess the performance of a new magnetic device to perform a side-to-side arteriovenous anastomosis in a dog model. Male fox hounds (25 kg) were treated preoperatively and daily postoperatively with clopidogrel bisulfate (Plavix) and aspirin. The femoral artery and vein were exposed unilaterally in 3 dogs and bilaterally in 4 dogs (n = 11 anastomoses). A 4-mm arteriotomy was performed, and 1 oval magnet 0.5 mm thick was inserted into the lumen of the artery and a second magnet was applied external to the artery, compressing and stabilizing the arterial wall to create a magnetic port. An identical venous magnetic port was created with another pair of oval magnets. When the 2 ports were allowed to approach each other, they self-aligned and magnetically coupled to complete the arteriovenous anastomosis. Patency was assessed for the first hour with direct observation, again after 9 weeks with duplex ultrasound scanning, and at 10 weeks under direct open observation. The anastomoses were explanted after 10 weeks. Hydrodynamic resistance was measured ex vivo on the final 8 anastomoses by measuring the pressure drop across an anastomosis with a known flow rate. After implantation, very high flow created visible turbulence and palpable vibration. All 11 anastomoses were patent under direct observation and palpation. Ten of 11 anastomoses were clearly patent on duplex scans, and patency of 1 anastomosis was questionable. Hydrodynamic resistance averaged 0.73 +/- 0.33 mm Hg min/mL (mean +/- SEM). Vascular anastomoses performed with magnets demonstrated feasibility; exhibited 100% patency after 10 weeks in a dog arteriovenous shunt model; lacked apparent aneurysm or other potentially catastrophic failure; demonstrated remodeling of the

  7. [Animal experimental study of compression anastomosis ring for low anterior resection].

    Science.gov (United States)

    Liang, Jian-Wei; Wang, Zheng; Zhang, Xing-Mao; Zhan, Da-Wei; Zhou, Zhi-Xiang

    2011-05-01

    To evaluate the feasibility and safety of nickel-titanium compression anastomosis ring (CAR27) in colorectal anastomosis after low anterior rectal resection in animal models. End-to-end colorectal anastomosis was performed using CAR27 in 6 experimental pigs after resection of the middle and lower third of the rectum. The animals were observed postoperatively for up to 56 days. Five pigs were sacrificed at day 14 and the other at day 56. Distance from anal verge to anastomosis and anastomotic circumference were measured. Histopathologic examination was performed. The median distance from anal verge was 5.3(4-6) cm. No anastomotic leak or other complications were observed. All the pigs recovered and gained weight. In 5 animals sacrificed at day 14, the mean circumference of the anastomosis was 6.8(6.5-7.0) cm, and histopathological examination showed mild inflammatory reaction and fibrosis. In the one sacrificed at day 56, the circumference expanded to 9.3 cm, and no inflammation and fibrosis were observed. Minor adhesion was noticed in only one pig, while smooth and intact serosa in the anastomosis was seen in the rest of the animals. CAR27 is a promising device for mid and low colorectal anastomosis.

  8. Early experience of the compression anastomosis ring (CARTM 27) in left-sided colon resection

    Science.gov (United States)

    Lee, Jung-Yeon; Woo, Jin-Hee; Choi, Hong-Jo; Park, Ki-Jae; Roh, Young-Hoon; Kim, Ki-Han; Lee, Hak-Yoon

    2011-01-01

    AIM: To evaluate clinical validity of the compression anastomosis ring (CAR™ 27) anastomosis in left-sided colonic resection. METHODS: A non-randomized prospective data collection was performed for patients undergoing an elective left-sided colon resection, followed by an anastomosis using the CAR™ 27 between November 2009 and January 2011. Eligibility criteria of the use of the CAR™ 27 were anastomoses between the colon and at or above the intraperitoneal rectum. The primary short-term clinical endpoint, rate of anastomotic leakage, and other clinical outcomes, including intra- and postoperative complications, length of operation time and hospital stay, and the ring elimination time were evaluated. RESULTS: A total of 79 patients (male, 43; median age, 64 years) underwent an elective left-sided colon resection, followed by an anastomosis using the CAR™ 27. Colectomy was performed laparoscopically in 70 patients, in whom two patients converted to open procedure (2.9%). There was no surgical mortality. As an intraoperative complication, total disruption of the anastomosis occurred by premature enforced tension on the proximal segment of the anastomosis in one patient. The ring was removed and another new CAR™ 27 anastomosis was constructed. One patient with sigmoid colon cancer showed postoperative anastomotic leakage after 6 d postoperatively and temporary diverting ileostomy was performed. Exact date of expulsion of the ring could not be recorded because most patients were not aware that the ring had been expelled. No patients manifested clinical symptoms of anastomotic stricture. CONCLUSION: Short-term evaluation of the CAR™ 27 anastomosis in elective left colectomy suggested it to be a safe and efficacious alternative to the standard hand-sewn or stapling technique. PMID:22147979

  9. Early experience of the compression anastomosis ring (CAR™ 27) in left-sided colon resection.

    Science.gov (United States)

    Lee, Jung-Yeon; Woo, Jin-Hee; Choi, Hong-Jo; Park, Ki-Jae; Roh, Young-Hoon; Kim, Ki-Han; Lee, Hak-Yoon

    2011-11-21

    To evaluate clinical validity of the compression anastomosis ring (CAR™ 27) anastomosis in left-sided colonic resection. A non-randomized prospective data collection was performed for patients undergoing an elective left-sided colon resection, followed by an anastomosis using the CAR™ 27 between November 2009 and January 2011. Eligibility criteria of the use of the CAR™ 27 were anastomoses between the colon and at or above the intraperitoneal rectum. The primary short-term clinical endpoint, rate of anastomotic leakage, and other clinical outcomes, including intra- and postoperative complications, length of operation time and hospital stay, and the ring elimination time were evaluated. A total of 79 patients (male, 43; median age, 64 years) underwent an elective left-sided colon resection, followed by an anastomosis using the CAR™ 27. Colectomy was performed laparoscopically in 70 patients, in whom two patients converted to open procedure (2.9%). There was no surgical mortality. As an intraoperative complication, total disruption of the anastomosis occurred by premature enforced tension on the proximal segment of the anastomosis in one patient. The ring was removed and another new CAR™ 27 anastomosis was constructed. One patient with sigmoid colon cancer showed postoperative anastomotic leakage after 6 d postoperatively and temporary diverting ileostomy was performed. Exact date of expulsion of the ring could not be recorded because most patients were not aware that the ring had been expelled. No patients manifested clinical symptoms of anastomotic stricture. Short-term evaluation of the CAR™ 27 anastomosis in elective left colectomy suggested it to be a safe and efficacious alternative to the standard hand-sewn or stapling technique.

  10. Anastomotic leakage after low anterior resection for rectal cancer: comparison of stapled versus compression anastomosis.

    Science.gov (United States)

    Dauser, Bernhard; Braunschmid, Tamara; Ghaffari, Shahbaz; Riss, Stefan; Stift, Anton; Herbst, Friedrich

    2013-10-01

    Surgical technique and perioperative management in rectal cancer surgery have been substantially improved and standardized during the last decades. However, anastomotic leakage following low anterior resection still is a significant problem. Based on animal experimental data of improved healing of compression anastomosis, we hypothesized that a compression anastomotic device might improve healing rates of the highest-risk anastomoses. All low anterior resections for rectal cancer performed or directly supervised by the senior author between January 2004 and June 2012 were analyzed. Only patients with a stapled or compression anastomosis located within 6 cm from the anal verge were included. Until December 2008, circular staplers were employed, while since January 2009, a novel compression anastomotic device was used for rectal reconstruction exclusively. Out of 197 patients operated for rectal cancer, a total of 96 (34 females, 35.4 %) fulfilled inclusion criteria. Fifty-eight (60.4 %) were reconstructed with circular staplers and 38 (39.6 %) using a compression anastomotic device. Significantly, more laparoscopic procedures were recorded in the compression anastomosis group, but distribution of gender, age, body mass index, American Society of Anaesthesiologists score, rate of preoperative radiotherapy, tumor staging, or stoma diversion rate were similar. Anastomotic leakage was observed in seven cases (7/58, 12.1 %) in the stapled and twice (2/38, 5.3 %) in the compression anastomosis group (p = 0.26). In this series, rectal reconstruction following low anterior resection using a novel compression anastomotic device was safe and (at least) equally effective compared to traditional circular staplers concerning leak rate.

  11. The use of shape memory compression anastomosis clips in cholecystojejunostomy in pigs – a preliminary study

    Directory of Open Access Journals (Sweden)

    Piotr Holak

    2015-01-01

    Full Text Available This paper reports on the use of compression anastomosis clips (CAC in cholecystoenterostomy in an animal model. Cholecystojejunostomy was performed in 6 pigs using implants made of nickel-titanium alloy in the form of elliptical springs with two-way shape memory. The applied procedure led to the achievement of tight anastomosis with a minimal number of complications and positive results of histopathological evaluations of the anastomotic site. The results of the study indicate that shape memory NiTi clips are a promising surgical tool for cholecystoenterostomy in cats and dogs.

  12. Compression method of anastomosis of large intestines by implants with memory of shape: alternative to traditional sutures

    Directory of Open Access Journals (Sweden)

    F. Sh. Aliev

    2015-01-01

    Full Text Available Research objective. To prove experimentally the possibility of forming a compression colonic anastomoses using nickel-titanium devices in comparison with traditional methods of anastomosis. Materials and methods. In experimental studies the quality of the compression anastomosis of the colon in comparison with sutured and stapled anastomoses was performed. There were three experimental groups in mongrel dogs formed: in the 1st series (n = 30 compression anastomoses nickel-titanium implants were formed; in the 2nd (n = 25 – circular stapling anastomoses; in the 3rd (n = 25 – ligature way to Mateshuk– Lambert. In the experiment the physical durability, elasticity, and biological tightness, morphogenesis colonic anastomoses were studied. Results. Optimal sizes of compression devices are 32 × 18 and 28 × 15 mm with a wire diameter of 2.2 mm, the force of winding compression was 740 ± 180 g/mm2. Compression suture has a higher physical durability compared to stapled (W = –33.0; p < 0.05 and sutured (W = –28.0; p < 0.05, higher elasticity (p < 0.05 in all terms of tests and biological tightness since 3 days (p < 0.001 after surgery. The regularities of morphogenesis colonic anastomoses allocated by 4 periods of the regeneration of intestinal suture. Conclusion. Obtained experimental data of the use of compression anastomosis of the colon by the nickel-titanium devices are the convincing arguments for their clinical application. 

  13. Magnetic compression into Brillouin flow

    International Nuclear Information System (INIS)

    Becker, R.

    1977-01-01

    The trajectories of beam edge electrons are calculated in the transition region between an electrostatic gun and an increasing magnetic field for various field shapes, transition length, and cathode fluxes, assuming that the resultant beam is of Brillouin flow type. The results give a good physical interpretation to the axial gradient of the magnetic field being responsible for the amount of magnetic compression and also for the proper injection conditions. Therefore it becomes possible to predict from the known characteristics of any fairly laminary electrostatic gun the necessary axial gradient of the magnetic field and the axial position of the gun with respect to the field build-up. (orig.) [de

  14. A modular magnetic anastomotic device for minimally invasive digestive anastomosis: proof of concept and preliminary data in the pig model.

    Science.gov (United States)

    Diana, Michele; Mutter, Didier; Lindner, Véronique; Vix, Michel; Chung, Hyunsoo; Demartines, Nicolas; Marescaux, Jacques

    2014-05-01

    The aim of our study was to assess the feasibility of minimally invasive digestive anastomosis using a modular flexible magnetic anastomotic device made up of a set of two flexible chains of magnetic elements. The assembly possesses a non-deployed linear configuration which allows it to be introduced through a dedicated small-sized applicator into the bowel where it takes the deployed form. A centering suture allows the mating between the two parts to be controlled in order to include the viscerotomy between the two magnetic rings and the connected viscera. Eight pigs were involved in a 2-week survival experimental study. In five colorectal anastomoses, the proximal device was inserted by a percutaneous endoscopic technique, and the colon was divided below the magnet. The distal magnet was delivered transanally to connect with the proximal magnet. In three jejunojejunostomies, the first magnetic chain was injected in its linear configuration through a small enterotomy. Once delivered, the device self-assembled into a ring shape. A second magnet was injected more distally through the same port. The centering sutures were tied together extracorporeally and, using a knot pusher, magnets were connected. Ex vivo strain testing to determine the compression force delivered by the magnetic device, burst pressure of the anastomosis, and histology were performed. Mean operative time including endoscopy was 69.2 ± 21.9 min, and average time to full patency was 5 days for colorectal anastomosis. Operative times for jejunojejunostomies were 125, 80, and 35 min, respectively. The postoperative period was uneventful. Burst pressure of all anastomoses was ≥ 110 mmHg. Mean strain force to detach the devices was 6.1 ± 0.98 and 12.88 ± 1.34 N in colorectal and jejunojejunal connections, respectively. Pathology showed a mild-to-moderate inflammation score. The modular magnetic system showed enormous potential to create minimally invasive digestive anastomoses, and may represent

  15. Adiabatic compression and radiative compression of magnetic fields

    International Nuclear Information System (INIS)

    Woods, C.H.

    1980-01-01

    Flux is conserved during mechanical compression of magnetic fields for both nonrelativistic and relativistic compressors. However, the relativistic compressor generates radiation, which can carry up to twice the energy content of the magnetic field compressed adiabatically. The radiation may be either confined or allowed to escape

  16. Safety and efficacy of the NiTi Shape Memory Compression Anastomosis Ring (CAR/ColonRing) for end-to-end compression anastomosis in anterior resection or low anterior resection.

    Science.gov (United States)

    Kang, Jeonghyun; Park, Min Geun; Hur, Hyuk; Min, Byung Soh; Lee, Kang Young; Kim, Nam Kyu

    2013-04-01

    Compression anastomoses may represent an improvement over traditional hand-sewn or stapled techniques. This prospective exploratory study aimed to assess the efficacy and complication rates in patients undergoing anterior resection (AR) or low anterior resection (LAR) anastomosed with a novel end-to-end compression anastomosis ring, the ColonRing. In all, 20 patients (13 male) undergoing AR or LAR were enrolled to be anastomosed using the NiTi Shape Memory End-to-End Compression Anastomosis Ring (NiTi Medical Technologies Ltd, Netanya, Israel). Demographic, intraoperative, and postoperative data were collected. Patients underwent AR (11/20) or LAR using laparoscopy (75%), robotic (10%) surgery, or an open laparotomy (15%) approach, with a median anastomotic level of 14.5 cm (range, 4-25 cm). Defunctioning loop ileostomies were formed in 6 patients for low anastomoses. Surgeons rated the ColonRing device as either easy or very easy to use. One patient developed an anastomotic leakage in the early postoperative period; there were no late postoperative complications. Mean time to passage of first flatus and commencement of oral fluids was 2.5 days and 3.2 days, respectively. Average hospital stay was 12.6 days (range, 8-23 days). Finally, the device was expelled on average 15.3 days postoperatively without difficulty. This is the first study reporting results in a significant number of LAR patients and the first reported experience from South Korea; it shows that the compression technique is surgically feasible, easy to use, and without significant complication rates. A large randomized controlled trial is warranted to investigate the benefits of the ColonRing over traditional stapling techniques.

  17. Long-term patency of experimental magnetic compression gastroenteric anastomoses achieved with covered stents.

    Science.gov (United States)

    Cope, C; Ginsberg, G G

    2001-06-01

    Our aim was to evaluate the efficacy of a prototype "YO-YO"-shaped covered stent for keeping experimental magnetic compression gastroenteric fistulas patent for 6 months. Magnets were introduced perorally with endoscopic and fluoroscopic guidance and were mated across the gastric and jejunal walls of 5 dogs. After a mean of 5.5 days a 12-mm diameter YO-YO stent was placed perorally in the resulting fistula. The gastroenteric anastomosis (GEA) with stent was observed endoscopically and gastrographically at 1- to 2-month intervals. There was no morbidity and there were no significant weight changes. The GEA was widely patent at necropsy at 6 months (n = 4); partial membrane separation occurred at 5 months in the fifth dog. There was minor breakage of the stent prongs in 2 animals. Peroral creation of a stented magnetic compression GEA is safe and provides long-term patency. This technique may be potentially useful for managing gastric outlet obstruction caused by malignancy.

  18. Magnetic field compression using pinch-plasma

    International Nuclear Information System (INIS)

    Koyama, K.; Tanimoto, M.; Matsumoto, Y.; Veno, I.

    1987-01-01

    In a previous report, the method for ultra-high magnetic field compression by using the pinchplasma was discussed. It is summarized as follows. The experiment is performed with the Mather-type plasma focus device tau/sub 1/4/ = 2 μs, I=880 kA at V=20 kV). An initial DC magnetic field is fed by an electromagnet embedded in the inner electrode. The axial component of the magnetic field diverges from the maximum field of 1 kG on the surface of the inner electrode. The density profile deduced from a Mach-Zehnder interferogram with a 2-ns N/sub 2/-laser shows a density dip lasting for 30 ns along the axes. Using the measured density of 8 x 10/sup 18/ cm/sup -3/, the temperature of 1.5 keV and the pressure balance relation, the magnitude of the trapped magnetic field is estimated to be 1.0 MG. The magnitude of the compressed magnetic field is also measured by Faraday rotation in a single-mode quartz fiber and a magnetic pickup soil. A protective polyethylene tube (3-mm o.d.) is used along the central axis through the inner electrode and the discharge chamber. The peak value of the compressed field range from 150 to 190 kG. No signal of the magnetic field appears up to the instance of the maximum pinch

  19. Velocity and Magnetic Compressions in FEL Drivers

    CERN Document Server

    Serafini, L

    2005-01-01

    We will compare merits and issues of these two techniques suitable for increasing the peak current of high brightness electron beams. The typical range of applicability is low energy for the velocity bunching and middle to high energy for magnetic compression. Velocity bunching is free from CSR effects but requires very high RF stability (time jitters), as well as a dedicated additional focusing and great cure in the beam transport: it is very well understood theoretically and numerical simulations are pretty straightforward. Several experiments of velocity bunching have been performed in the past few years: none of them, nevertheless, used a photoinjector designed and optimized for that purpose. Magnetic compression is a much more consolidated technique: CSR effects and micro-bunch instabilities are its main drawbacks. There is a large operational experience with chicanes used as magnetic compressors and their theoretical understanding is quite deep, though numerical simulations of real devices are still cha...

  20. International magnetic pulse compression workshop: (Proceedings)

    Energy Technology Data Exchange (ETDEWEB)

    Kirbie, H.C.; Newton, M.A.; Siemens, P.D.

    1991-04-01

    A few individuals have tried to broaden the understanding of specific and salient pulsed-power topics. One such attempt is this documentation of a workshop on magnetic switching as it applies primarily to pulse compression (power transformation), affording a truly international perspective by its participants under the initiative and leadership of Hugh Kirbie and Mark Newton of the Lawrence Livermore National Laboratory (LLNL) and supported by other interested organizations. During the course of the Workshop at Granlibakken, a great deal of information was amassed and a keen insight into both the problems and opportunities as to the use of this switching approach was developed. The segmented workshop format proved ideal for identifying key aspects affecting optimum performance in a variety of applications. Individual groups of experts addressed network and system modeling, magnetic materials, power conditioning, core cooling and dielectrics, and finally circuits and application. At the end, they came together to consolidate their input and formulate the workshop's conclusions, identifying roadblocks or suggesting research projects, particularly as they apply to magnetic switching's trump card--its high-average-power-handling capability (at least on a burst-mode basis). The workshop was especially productive both in the quality and quantity of information transfer in an environment conducive to a free and open exchange of ideas. We will not delve into the organization proper of this meeting, rather we wish to commend to the interested reader this volume, which provides the definitive and most up-to-date compilation on the subject of magnetic pulse compression from underlying principles to current state of the art as well as the prognosis for the future of magnetic pulse compression as a consensus of the workshop's organizers and participants.

  1. International magnetic pulse compression workshop: [Proceedings

    International Nuclear Information System (INIS)

    Kirbie, H.C.; Newton, M.A.; Siemens, P.D.

    1991-04-01

    A few individuals have tried to broaden the understanding of specific and salient pulsed-power topics. One such attempt is this documentation of a workshop on magnetic switching as it applies primarily to pulse compression (power transformation), affording a truly international perspective by its participants under the initiative and leadership of Hugh Kirbie and Mark Newton of the Lawrence Livermore National Laboratory (LLNL) and supported by other interested organizations. During the course of the Workshop at Granlibakken, a great deal of information was amassed and a keen insight into both the problems and opportunities as to the use of this switching approach was developed. The segmented workshop format proved ideal for identifying key aspects affecting optimum performance in a variety of applications. Individual groups of experts addressed network and system modeling, magnetic materials, power conditioning, core cooling and dielectrics, and finally circuits and application. At the end, they came together to consolidate their input and formulate the workshop's conclusions, identifying roadblocks or suggesting research projects, particularly as they apply to magnetic switching's trump card--its high-average-power-handling capability (at least on a burst-mode basis). The workshop was especially productive both in the quality and quantity of information transfer in an environment conducive to a free and open exchange of ideas. We will not delve into the organization proper of this meeting, rather we wish to commend to the interested reader this volume, which provides the definitive and most up-to-date compilation on the subject of magnetic pulse compression from underlying principles to current state of the art as well as the prognosis for the future of magnetic pulse compression as a consensus of the workshop's organizers and participants

  2. Role of compressibility on driven magnetic reconnection

    International Nuclear Information System (INIS)

    Sato, T.; Hayashi, T.; Watanabe, K.; Horiuchi, R.; Tanaka, M.; Sawairi, N.; Kusano, K.

    1991-08-01

    Whether it is induced by an ideal (current driven) instability or by an external force, plasma flow causes a change in the magnetic field configuration and often gives rise to a current intensification locally, thereby a fast driven reconnection being driven there. Many dramatic phenomena in magnetically confined plasmas such as magnetospheric substorms, solar flares, MHD self-organization and tokamak sawtooth crash, may be attributed to this fast driven reconnection. Using a fourth order MHD simulation code it is confirmed that compressibility of the plasma plays a crucial role in leading to a fast (MHD time scale) driven reconnection. This indicates that the incompressible representation is not always applicable to the study of a global dynamical behavior of a magnetically confined plasma. (author)

  3. SEED BANKS FOR MAGNETIC FLUX COMPRESSION GENERATORS

    Energy Technology Data Exchange (ETDEWEB)

    Fulkerson, E S

    2008-05-14

    In recent years the Lawrence Livermore National Laboratory (LLNL) has been conducting experiments that require pulsed high currents to be delivered into inductive loads. The loads fall into two categories (1) pulsed high field magnets and (2) the input stage of Magnetic Flux Compression Generators (MFCG). Three capacitor banks of increasing energy storage and controls sophistication have been designed and constructed to drive these loads. One bank was developed for the magnet driving application (20kV {approx} 30kJ maximum stored energy.) Two banks where constructed as MFCG seed banks (12kV {approx} 43kJ and 26kV {approx} 450kJ). This paper will describe the design of each bank including switching, controls, circuit protection and safety.

  4. Magnetic pulse compression circuits for plasma devices

    Energy Technology Data Exchange (ETDEWEB)

    Georgescu, N; Zoita, V; Presura, R [Inst. of Physics and Technology of Radiation Devices, Bucharest (Romania)

    1997-12-31

    Two magnetic pulse compression circuits (MPCC), for two different plasma devices, are presented. The first is a 20 J/pulse, 3-stage circuit designed to trigger a low pressure discharge. The circuit has 16-18 kV working voltage, and 200 nF in each stage. The saturable inductors are realized with toroidal 25 {mu}m strip-wound cores, made of a Fe-Ni alloy, with 1.5 T saturation induction. The total magnetic volume is around 290 cm{sup 3}. By using a 25 kV/1 A thyratron as a primary switch, the time compression is from 3.5 {mu}s to 450 ns, in a short-circuit load. The second magnetic pulser is a 200 J/pulse circuit, designed to drive a high average power plasma focus soft X-ray source, for X-ray microlithography as the main application. The 3-stage pulser should supply a maximum load current of 100 kA with a rise-time of 250 - 300 ns. The maximum pulse voltage applied on the plasma discharge chamber is around 20 - 25 kV. The three saturable inductors in the circuit are made of toroidal strip-wound cores with METGLAS 2605 CO amorphous alloy as the magnetic material. The total, optimized mass of the magnetic material is 34 kg. The maximum repetition rate is limited at 100 Hz by the thyratron used in the first stage of the circuit, the driver supplying to the load about 20 kW average power. (author). 1 tab., 3 figs., 3 refs.

  5. Magnetic compression/magnetized target fusion (MAGO/MTF)

    International Nuclear Information System (INIS)

    Kirkpatrick, R.C.; Lindemuth, I.R.

    1997-03-01

    Magnetized Target Fusion (MTF) was reported in two papers at the First Symposium on Current Trends in International Fusion Research. MTF is intermediate between two very different mainline approaches to fusion: Inertial Confinement Fusion (ICF) and magnetic confinement fusion (MCF). The only US MTF experiments in which a target plasma was compressed were the Sandia National Laboratory ''Phi targets''. Despite the very interesting results from that series of experiments, the research was not pursued, and other embodiments of MTF concept such as the Fast Liner were unable to attract the financial support needed for a firm proof of principle. A mapping of the parameter space for MTF showed the significant features of this approach. The All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) has an on-going interest in this approach to thermonuclear fusion, and Los Alamos National Laboratory (LANL) and VNIIEF have done joint target plasma generation experiments relevant to MTF referred to as MAGO (transliteration of the Russian acronym for magnetic compression). The MAGO II experiment appears to have achieved on the order of 200 eV and over 100 KG, so that adiabatic compression with a relatively small convergence could bring the plasma to fusion temperatures. In addition, there are other experiments being pursued for target plasma generation and proof of principle. This paper summarizes the previous reports on MTF and MAGO and presents the progress that has been made over the past three years in creating a target plasma that is suitable for compression to provide a scientific proof of principle experiment for MAGO/MTF

  6. Compressed magnetic flux amplifier with capacitive load

    International Nuclear Information System (INIS)

    Stuetzer, O.M.

    1980-03-01

    A first-order analysis is presented for a compressed magnetic flux (CMF) current amplifier working into a load with a capacitive component. Since the purpose of the investigation was to gain a general understanding of the arrangement, a number of approximations and limitations were accepted. The inductance of the transducer varies with time; the inductance/resistance/capacitance (LRC) circuit therefore is parametric and solutions are different for the stable regime (high C), the oscillation regime (low C), and the transition case. Solutions and performance depend strongly on circuit boundary conditions, i.e., energization of the circuit by either an injected current or by an applied capacitor charge. The behavior of current and energy amplification for the various cases are discussed in detail. A number of experiments with small CMF devices showed that the first-order theory presented predicts transducer performance well in the linear regime

  7. Buehler's anastomosis

    International Nuclear Information System (INIS)

    Grabbe, E.; Buecheler, E.

    1980-01-01

    The arc of Buehler between the celiac and superior mesenteric arteries has to be considered as an embryological persistence of the portion of the ventral longitudinal anastomosis. The collateral development of the anastomosis refers to a different hemodynamic in the upper visceral arteries. We discovered the arc of Buehler in 14 cases among 340 selective celiac and superior mesenteric arteriographic studies. Its existence permits conclusions about further angiographic procedures and facilitates the interpretation of visceral collaterals. (orig.) [de

  8. Task-oriented lossy compression of magnetic resonance images

    Science.gov (United States)

    Anderson, Mark C.; Atkins, M. Stella; Vaisey, Jacques

    1996-04-01

    A new task-oriented image quality metric is used to quantify the effects of distortion introduced into magnetic resonance images by lossy compression. This metric measures the similarity between a radiologist's manual segmentation of pathological features in the original images and the automated segmentations performed on the original and compressed images. The images are compressed using a general wavelet-based lossy image compression technique, embedded zerotree coding, and segmented using a three-dimensional stochastic model-based tissue segmentation algorithm. The performance of the compression system is then enhanced by compressing different regions of the image volume at different bit rates, guided by prior knowledge about the location of important anatomical regions in the image. Application of the new system to magnetic resonance images is shown to produce compression results superior to the conventional methods, both subjectively and with respect to the segmentation similarity metric.

  9. Projectile-power-compressed magnetic-field pulse generator

    International Nuclear Information System (INIS)

    Barlett, R.H.; Takemori, H.T.; Chase, J.B.

    1983-01-01

    Design considerations and experimental results are presented of a compressed magnetic field pulsed energy source. A 100-mm-diameter, gun-fired projectile of approx. 2MJ kinetic energy was the input energy source. An initial magnetic field was trapped and compressed by the projectile. With a shorted load, a magajoule in a nanohenry was the design goal, i.e., 50 percent energy transformation from kinetic to magnetic. Five percent conversion was the highest recorded before gauge failure

  10. Magnetic surface compression heating in the heliotron device

    International Nuclear Information System (INIS)

    Uo, K.; Motojima, O.

    1982-01-01

    The slow adiabatic compression of the plasma in the heliotron device is examined. It has a prominent characteristic that the plasma equilibrium always exists at each stage of the compression. The heating efficiency is calculated. We show the possible access to fusion. A large amount of the initial investment for the heating system (NBI or RF) is reduced by using the magnetic surface compression heating. (author)

  11. Compression of magnetized target in the magneto-inertial fusion

    Science.gov (United States)

    Kuzenov, V. V.

    2017-12-01

    This paper presents a mathematical model, numerical method and results of the computer analysis of the compression process and the energy transfer in the target plasma, used in magneto-inertial fusion. The computer simulation of the compression process of magnetized cylindrical target by high-power laser pulse is presented.

  12. Compression of turbulent magnetized gas in giant molecular clouds

    Science.gov (United States)

    Birnboim, Yuval; Federrath, Christoph; Krumholz, Mark

    2018-01-01

    Interstellar gas clouds are often both highly magnetized and supersonically turbulent, with velocity dispersions set by a competition between driving and dissipation. This balance has been studied extensively in the context of gases with constant mean density. However, many astrophysical systems are contracting under the influence of external pressure or gravity, and the balance between driving and dissipation in a contracting, magnetized medium has yet to be studied. In this paper, we present three-dimensional magnetohydrodynamic simulations of compression in a turbulent, magnetized medium that resembles the physical conditions inside molecular clouds. We find that in some circumstances the combination of compression and magnetic fields leads to a rate of turbulent dissipation far less than that observed in non-magnetized gas, or in non-compressing magnetized gas. As a result, a compressing, magnetized gas reaches an equilibrium velocity dispersion much greater than would be expected for either the hydrodynamic or the non-compressing case. We use the simulation results to construct an analytic model that gives an effective equation of state for a coarse-grained parcel of the gas, in the form of an ideal equation of state with a polytropic index that depends on the dissipation and energy transfer rates between the magnetic and turbulent components. We argue that the reduced dissipation rate and larger equilibrium velocity dispersion has important implications for the driving and maintenance of turbulence in molecular clouds and for the rates of chemical and radiative processes that are sensitive to shocks and dissipation.

  13. Efficacy and safety of a NiTi CAR 27 compression ring for end-to-end anastomosis compared with conventional staplers: A real-world analysis in Chinese colorectal cancer patients

    Science.gov (United States)

    Lu, Zhenhai; Peng, Jianhong; Li, Cong; Wang, Fulong; Jiang, Wu; Fan, Wenhua; Lin, Junzhong; Wu, Xiaojun; Wan, Desen; Pan, Zhizhong

    2016-01-01

    OBJECTIVES: This study aimed to evaluate the safety and efficacy of a new nickel-titanium shape memory alloy compression anastomosis ring, NiTi CAR 27, in constructing an anastomosis for colorectal cancer resection compared with conventional staples. METHODS: In total, 234 consecutive patients diagnosed with colorectal cancer receiving sigmoidectomy and anterior resection for end-to-end anastomosis from May 2010 to June 2012 were retrospectively analyzed. The postoperative clinical parameters, postoperative complications and 3-year overall survival in 77 patients using a NiTi CAR 27 compression ring (CAR group) and 157 patients with conventional circular staplers (STA group) were compared. RESULTS: There were no statistically significant differences between the patients in the two groups in terms of general demographics and tumor features. A clinically apparent anastomotic leak occurred in 2 patients (2.6%) in the CAR group and in 5 patients (3.2%) in the STA group (p=0.804). These eight patients received a temporary diverting ileostomy. One patient (1.3%) in the CAR group was diagnosed with anastomotic stricture through an electronic colonoscopy after 3 months postoperatively. The incidence of postoperative intestinal obstruction was comparable between the two groups (p=0.192). With a median follow-up duration of 39.6 months, the 3-year overall survival rate was 83.1% in the CAR group and 89.0% in the STA group (p=0.152). CONCLUSIONS: NiTi CAR 27 is safe and effective for colorectal end-to-end anastomosis. Its use is equivalent to that of the conventional circular staplers. This study suggests that NiTi CAR 27 may be a beneficial alternative in colorectal anastomosis in Chinese colorectal cancer patients. PMID:27276395

  14. [Gastro-entero anastomosis with flexible endoscope with the help of rare-earth magnets on biosynthetic model made of the gastrointestinal tract of slaughtered pigs].

    Science.gov (United States)

    Lukovich, Péter; Jónás, Attila; Bata, Pál; Tari, Krisztina; Váradi, Gábor; Kádár, Balázs; Mehdi, Sadat Akhavi; Kupcsulik, Péter

    2007-04-01

    Gastro-entero anastomosis with flexible endoscope with the help of rare-earth magnets on biosynthetic model made of the gastrointestinal tract of slaughtered pigs Numerous malignant diseases may cause gastric outlet obstruction. The surgical gastrointestinal bypass, besides the fact that it requires narcosis, is also associated with high risks for patients with poor general condition. Endoscopic insertion of self-expandable metal stent is less invasive, but often causes complications. In the last years some studies examined a new minimal invasive technique, in which magnets are used to create gastroenteric anastomosis. A biosynthetic model was developed from combined synthetic materials with biogenic specimens taken from slaughtered domestic pigs. The procedure was performed with endoscopic and fluoroscopic guidance. To increase X-ray contrast differences the model was put into physiological saline solution. Two rare-earth magnets (Br: 2500 Gauss, D: 10 mm) with central hole were inserted with the help of a guiding wire and duodenal probe. The first magnet was placed in the first jejunal loop; the second one was placed in the stomach. The gastric magnet was maneuvered using the endoscope. When the magnets reached the right position, the guiding wires were removed to let the magnets stick together. The pressure between the magnets will result in a sterile inflammation on the living tissue which develops adhesion between the bowels, and 7-10 days later anastomosis will develop as a result of the necrosis. The biosynthetic model could be used for training endoscopy without sacrificing animals. In the end of the procedure the magnets stuck together across gastric and jejunal walls in all ten cases successfully. By practice the period necessary for the procedure could be decreased from 40 to 20 minutes. The technique could be made with standard upper endoscope and instruments, and after practice on living animals it could potentially be a useful solution for complaints

  15. A design approach for systems based on magnetic pulse compression

    International Nuclear Information System (INIS)

    Praveen Kumar, D. Durga; Mitra, S.; Senthil, K.; Sharma, D. K.; Rajan, Rehim N.; Sharma, Archana; Nagesh, K. V.; Chakravarthy, D. P.

    2008-01-01

    A design approach giving the optimum number of stages in a magnetic pulse compression circuit and gain per stage is given. The limitation on the maximum gain per stage is discussed. The total system volume minimization is done by considering the energy storage capacitor volume and magnetic core volume at each stage. At the end of this paper, the design of a magnetic pulse compression based linear induction accelerator of 200 kV, 5 kA, and 100 ns with a repetition rate of 100 Hz is discussed with its experimental results

  16. Estimating the magnetic energy inside traveling compression regions

    Directory of Open Access Journals (Sweden)

    S. A. Kiehas

    2009-05-01

    Full Text Available We investigate a series of six TCRs (traveling compression regions, appearing in the course of a small substorm on 19 September 2001. Except for two of these TCRs, all Cluster spacecraft were located in the lobe and detected the typical signatures of TCRs, i.e., compressions in |B| and bipolar Bz variations. We use these perturbations in Bz for calculations on the magnetic energy inside the TCR and compare the amount of magnetic field energy with the kinetic energy inside the underlying plasma bulge. According to results obtained from theory, the amount of magnetic energy inside TCRs is about two times higher than the kinetic plasma energy inside the accompanied plasma bulge. We verify this theoretical result by first investigations of the magnetic field energy inside TCRs. The calculations lead to a magnetic energy in the order of 1010 Joule per RE for each of the TCRs.

  17. Self-similar compression of a magnetized plasma filled liner

    International Nuclear Information System (INIS)

    Felber, F.S.; Liberman, M.A.; Velikovich, A.L.

    1985-01-01

    New analytic, one-dimensional, self-similar solutions of magnetohydrodynamic equations describing the compression of a magnetized plasma by a thin cylindrical liner are presented. The solutions include several features that have not been included in an earlier self-similar solution of the equations of ideal magnetohydrodynamics. These features are the effects of finite plasma electrical conductivity, induction heating, thermal conductivity and related thermogalvanomagnetic effects, plasma turbulence, and plasma boundary effects. These solutions have been motivated by recent suggestions for production of ultrahigh magnetic fields by new methods. The methods involve radially imploding plasmas in which axial magnetic fields have been entrained. These methods may be capable of producing controlled magnetic fields up to approx. = 100 MG. Specific methods of implosion suggested were by ablative radial acceleration of a liner by a laser and by a gas-puff Z pinch. The model presented here addresses the first of these methods. The solutions derived here are used to estimate magnetic flux losses out of the compression volume, and to indicate conditions under which an impulsively-accelerated, plasma-filled liner may compress an axial magnetic field to large magnitude

  18. Injection, compression and confinement of electrons in a magnetic mirror

    International Nuclear Information System (INIS)

    Fisher, A.

    1975-01-01

    A Helmholtz coil configuration has been constructed where the magnetic field can be increased to about 10 kGauss in 20 μsec. Electrons are injected from a hot tantalum filament between two plates across which a potential of about 5 keV is applied. The electric field E is perpendicular to the magnetic field B so that the direction of the E x B drift is radial--into the magnetic mirror. About 10 14 electrons were injected and about 10 13 electrons were trapped. The initial electron energy was about 5 keV and after compression 500 keV x-rays were observed. The confinement time is very sensitive to vacuum. Confinement times of milliseconds and good compression were observed at vacuum of 5.10 -5 torr or less. Above 5.10 -5 torr there was no trapping or compression. After a compressed ring of electrons was formed, it was released by a pulse applied to one of the Helmholtz coils that reduced the field. Ejection of the electron ring was observed by x-ray measurements

  19. Magnetic Compression Experiment at General Fusion with Simulation Results

    Science.gov (United States)

    Dunlea, Carl; Khalzov, Ivan; Hirose, Akira; Xiao, Chijin; Fusion Team, General

    2017-10-01

    The magnetic compression experiment at GF was a repetitive non-destructive test to study plasma physics applicable to Magnetic Target Fusion compression. A spheromak compact torus (CT) is formed with a co-axial gun into a containment region with an hour-glass shaped inner flux conserver, and an insulating outer wall. External coil currents keep the CT off the outer wall (levitation) and then rapidly compress it inwards. The optimal external coil configuration greatly improved both the levitated CT lifetime and the rate of shots with good compressional flux conservation. As confirmed by spectrometer data, the improved levitation field profile reduced plasma impurity levels by suppressing the interaction between plasma and the insulating outer wall during the formation process. We developed an energy and toroidal flux conserving finite element axisymmetric MHD code to study CT formation and compression. The Braginskii MHD equations with anisotropic heat conduction were implemented. To simulate plasma / insulating wall interaction, we couple the vacuum field solution in the insulating region to the full MHD solution in the remainder of the domain. We see good agreement between simulation and experiment results. Partly funded by NSERC and MITACS Accelerate.

  20. A Compressed Sensing Framework for Magnetic Resonance Fingerprinting

    OpenAIRE

    Davies, Mike; Puy, Gilles; Vandergheynst, Pierre; Wiaux, Yves

    2013-01-01

    Inspired by the recently proposed Magnetic Resonance Fingerprinting (MRF) technique, we develop a principled compressed sensing framework for quantitative MRI. The three key components are: a random pulse excitation sequence following the MRF technique; a random EPI subsampling strategy and an iterative projection algorithm that imposes consistency with the Bloch equations. We show that theoretically, as long as the excitation sequence possesses an appropriate form of persistent excitation, w...

  1. Pressure and compressibility factor of bidisperse magnetic fluids

    Science.gov (United States)

    Minina, Elena S.; Blaak, Ronald; Kantorovich, Sofia S.

    2018-04-01

    In this work, we investigate the pressure and compressibility factors of bidisperse magnetic fluids with relatively weak dipolar interactions and different granulometric compositions. In order to study these properties, we employ the method of diagram expansion, taking into account two possible scenarios: (1) dipolar particles repel each other as hard spheres; (2) the polymer shell on the surface of the particles is modelled through a soft-sphere approximation. The theoretical predictions of the pressure and compressibility factors of bidisperse ferrofluids at different granulometric compositions are supported by data obtained by means of molecular dynamics computer simulations, which we also carried out for these systems. Both theory and simulations reveal that the pressure and compressibility factors decrease with growing dipolar correlations in the system, namely with an increasing fraction of large particles. We also demonstrate that even if dipolar interactions are too weak for any self-assembly to take place, the interparticle correlations lead to a qualitative change in the behaviour of the compressibility factors when compared to that of non-dipolar spheres, making the dependence monotonic.

  2. The phenomenon of radiative compression in dense magnetized plasmas

    International Nuclear Information System (INIS)

    Choi, Peter

    1998-01-01

    Full text: Localized regions of extremely high energy density have long been observed in dense magnetized plasma, created in different experiments, including vacuum spark, exploding wire, Z-pinch and plasma focus. The physical dimensions of these regions are typically tens to hundreds of microns with a characteristic temperature of few hundred eV upward. A theory of self-compression under enhanced cooling, when the radiation rate exceeds the joule heating rate, was first put forward by Shearer to explain the possible responsible mechanism. More recent work suggests that a radiative collapse formalism could indeed produce eaters of ultra-high density. In the paper the experimental evidences are examined, and the applicability limit of the radiative collapse picture is discussed, when the properties of the driving generator are considered. A new set of relations connecting the driver parameters and the limiting size of the compression is proposed

  3. SVD compression for magnetic resonance fingerprinting in the time domain.

    Science.gov (United States)

    McGivney, Debra F; Pierre, Eric; Ma, Dan; Jiang, Yun; Saybasili, Haris; Gulani, Vikas; Griswold, Mark A

    2014-12-01

    Magnetic resonance (MR) fingerprinting is a technique for acquiring and processing MR data that simultaneously provides quantitative maps of different tissue parameters through a pattern recognition algorithm. A predefined dictionary models the possible signal evolutions simulated using the Bloch equations with different combinations of various MR parameters and pattern recognition is completed by computing the inner product between the observed signal and each of the predicted signals within the dictionary. Though this matching algorithm has been shown to accurately predict the MR parameters of interest, one desires a more efficient method to obtain the quantitative images. We propose to compress the dictionary using the singular value decomposition, which will provide a low-rank approximation. By compressing the size of the dictionary in the time domain, we are able to speed up the pattern recognition algorithm, by a factor of between 3.4-4.8, without sacrificing the high signal-to-noise ratio of the original scheme presented previously.

  4. Stent placement of gastroenteric anastomoses formed by magnetic compression.

    Science.gov (United States)

    Cope, C; Clark, T W; Ginsberg, G; Habecker, P

    1999-01-01

    To evaluate the use of stents for prolonging the patency of gastroenteric anastomoses (GEA) induced by magnet compression. Rare earth magnets were inserted perorally and serially in 15 dogs so as to mate across the gastric and jejunal walls. After magnet excretion, the resulting GEA was identified endoscopically, dilated (n = 1), and stented with bare (n = 2) or partially covered (n = 6) flared 10-mm or 12-mm Z stents. The GEA was followed at 2-4-week intervals for patency; malfunctioning shunts were irrigated, or dilated with angioplasty balloons. Gross and histologic examination of the anastomotic tissues was performed in 14 animals. Magnet pairs were excreted in 5-7 days. Of the 19 magnet placements in 15 animals, stent placement was not possible because of early GEA closure (n = 6), failure to locate (n = 2), pancreatic abscess (n = 1), and magnet perforation with peritonitis (n = 1). Estimated duration of GEA patency was 19 days after balloon dilation, 40-64 days with bare Z stents, and 58-147 days (mean, 90 days) with partially covered Z stents. Shunt function was commonly hindered by bezoars. Stent narrowing or occlusion was caused by tissue overgrowth through bare stents (n = 2), between covered stent struts and through partially detached membrane (n = 2). Serious morbidity (n = 2) was due to malpositioned magnets across the pancreas in one animal and gastric perforation in the other. One dog was euthanized because of unsuspected kidney infection. Partially covered stents significantly extend the anatomic patency rate of magnetic GEA to 7 weeks or more. Functional patency is frequently impaired by bezoars. Ongoing improvements in covered stent design should provide longer-term GEA patency.

  5. Intense synchrotron radiation from a magnetically compressed relativistic electron layer

    International Nuclear Information System (INIS)

    Shearer, J.W.; Nowak, D.A.; Garelis, E.; Condit, W.C.

    1975-10-01

    Using a simple model of a relativistic electron layer rotating in an axial magnetic field, energy gain by an increasing magnetic field and energy loss by synchrotron radiation were considered. For a typical example, initial conditions were approximately 8 MeV electron in approximately 14 kG magnetic field, at a layer radius of approximately 20 mm, and final conditions were approximately 4 MG magnetic field approximately 100 MeV electron layer energy at a layer radius of approximately 1.0 mm. In the final state, the intense 1-10 keV synchrotron radiation imposes an electron energy loss time constant of approximately 100 nanoseconds. In order to achieve these conditions in practice, the magnetic field must be compressed by an imploding conducting liner; preferably two flying rings in order to allow the synchrotron radiation to escape through the midplane. The synchrotron radiation loss rate imposes a lower limit to the liner implosion velocity required to achieve a given final electron energy (approximately 1 cm/μsec in the above example). In addition, if the electron ring can be made sufficiently strong (field reversed), the synchrotron radiation would be a unique source of high intensity soft x-radiation

  6. Use of magnetic compression to support turbine engine rotors

    Science.gov (United States)

    Pomfret, Chris J.

    1994-01-01

    Ever since the advent of gas turbine engines, their rotating disks have been designed with sufficient size and weight to withstand the centrifugal forces generated when the engine is operating. Unfortunately, this requirement has always been a life and performance limiting feature of gas turbine engines and, as manufacturers strive to meet operator demands for more performance without increasing weight, the need for innovative technology has become more important. This has prompted engineers to consider a fundamental and radical breakaway from the traditional design of turbine and compressor disks which have been in use since the first jet engine was flown 50 years ago. Magnetic compression aims to counteract, by direct opposition rather than restraint, the centrifugal forces generated within the engine. A magnetic coupling is created between a rotating disk and a stationary superconducting coil to create a massive inwardly-directed magnetic force. With the centrifugal forces opposed by an equal and opposite magnetic force, the large heavy disks could be dispensed with and replaced with a torque tube to hold the blades. The proof of this concept has been demonstrated and the thermal management of such a system studied in detail; this aspect, especially in the hot end of a gas turbine engine, remains a stiff but not impossible challenge. The potential payoffs in both military and commercial aviation and in the power generation industry are sufficient to warrant further serious studies for its application and optimization.

  7. Self-compression of intense short laser pulses in relativistic magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Olumi, M.; Maraghechi, B., E-mail: behrouz@aut.ac.ir [Department of Physics, Amirkabir University of Technology, Post code 15916-34311 Tehran (Iran, Islamic Republic of)

    2014-11-15

    The compression of a relativistic Gaussian laser pulse in a magnetized plasma is investigated. By considering relativistic nonlinearity and using non-linear Schrödinger equation with paraxial approximation, a second-order differential equation is obtained for the pulse width parameter (in time) to demonstrate the longitudinal pulse compression. The compression of laser pulse in a magnetized plasma can be observed by the numerical solution of the equation for the pulse width parameter. The effects of magnetic field and chirping are investigated. It is shown that in the presence of magnetic field and negative initial chirp, compression of pulse is significantly enhanced.

  8. Magnetic resonance image compression using scalar-vector quantization

    Science.gov (United States)

    Mohsenian, Nader; Shahri, Homayoun

    1995-12-01

    A new coding scheme based on the scalar-vector quantizer (SVQ) is developed for compression of medical images. SVQ is a fixed-rate encoder and its rate-distortion performance is close to that of optimal entropy-constrained scalar quantizers (ECSQs) for memoryless sources. The use of a fixed-rate quantizer is expected to eliminate some of the complexity issues of using variable-length scalar quantizers. When transmission of images over noisy channels is considered, our coding scheme does not suffer from error propagation which is typical of coding schemes which use variable-length codes. For a set of magnetic resonance (MR) images, coding results obtained from SVQ and ECSQ at low bit-rates are indistinguishable. Furthermore, our encoded images are perceptually indistinguishable from the original, when displayed on a monitor. This makes our SVQ based coder an attractive compression scheme for picture archiving and communication systems (PACS), currently under consideration for an all digital radiology environment in hospitals, where reliable transmission, storage, and high fidelity reconstruction of images are desired.

  9. Development of ultra-short high voltage pulse technology using magnetic pulse compression

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Byung Heon; Kim, S. G.; Nam, S. M.; Lee, B. C.; Lee, S. M.; Jeong, Y. U.; Cho, S. O.; Jin, J. T.; Choi, H. L

    1998-01-01

    The control circuit for high voltage switches, the saturable inductor for magnetic assist, and the magnetic pulse compression circuit were designed, constructed, and tested. The core materials of saturable inductors in magnetic pulse compression circuit were amorphous metal and ferrite and total compression stages were 3. By the test, in high repetition rate, high pulse compression were certified. As a result of this test, it became possible to increase life-time of thyratrons and to replace thyratrons by solid-state semiconductor switches. (author). 16 refs., 16 tabs.

  10. Development of ultra-short high voltage pulse technology using magnetic pulse compression

    International Nuclear Information System (INIS)

    Cha, Byung Heon; Kim, S. G.; Nam, S. M.; Lee, B. C.; Lee, S. M.; Jeong, Y. U.; Cho, S. O.; Jin, J. T.; Choi, H. L.

    1998-01-01

    The control circuit for high voltage switches, the saturable inductor for magnetic assist, and the magnetic pulse compression circuit were designed, constructed, and tested. The core materials of saturable inductors in magnetic pulse compression circuit were amorphous metal and ferrite and total compression stages were 3. By the test, in high repetition rate, high pulse compression were certified. As a result of this test, it became possible to increase life-time of thyratrons and to replace thyratrons by solid-state semiconductor switches. (author). 16 refs., 16 tabs

  11. Losses in magnetic flux compression generators: Part 2, Radiation losses

    International Nuclear Information System (INIS)

    Fowler, C.M.

    1988-06-01

    This is the second monograph devoted to the analysis of flux losses in explosive driven magnetic flux compression generators. In the first monograph, flux losses from magnetic field penetration into conductor walls was studied by conventional diffusion theory. In the present report flux loss by radiation from the outer conductor walls is treated. Flux leakage rates through walls of finite thickness are first obtained by diffusion theory. It is shown, for normal wall thicknesses, that flux leakage is determined essentially by the wall conductance, defined as the product of wall thickness and wall conductivity. This remains true when the wall thickness is reduced to zero at unchanged conductance. In this case the wall is said to be coalesced. Solutions for a cavity bounded by a perfect conductor on one side and a coalesced wall on the other are then obtained using the complete Maxwell wave equations in both the cavity and free space beyond the coalesced wall. Several anomalies, noted earlier, that arise from diffusion analysis are resolved by the wave treatment. Conditions for the validity of the diffusion treatment are noted, and an expression is obtained within the framework of diffusion theory for energy radiated into space from the cavity walls. The free space wave equations are solved by using the method of characteristics in both the cavity and free space regions. An extension of the characteristic method to situations where the constitutive relations are non-linear is outlined in an appendix. For a special class of these relations, Riemann-like invariants are determined explicitly and used to solve a particular example

  12. A simple accurate chest-compression depth gauge using magnetic coils during cardiopulmonary resuscitation.

    Science.gov (United States)

    Kandori, Akihiko; Sano, Yuko; Zhang, Yuhua; Tsuji, Toshio

    2015-12-01

    This paper describes a new method for calculating chest compression depth and a simple chest-compression gauge for validating the accuracy of the method. The chest-compression gauge has two plates incorporating two magnetic coils, a spring, and an accelerometer. The coils are located at both ends of the spring, and the accelerometer is set on the bottom plate. Waveforms obtained using the magnetic coils (hereafter, "magnetic waveforms"), which are proportional to compression-force waveforms and the acceleration waveforms were measured at the same time. The weight factor expressing the relationship between the second derivatives of the magnetic waveforms and the measured acceleration waveforms was calculated. An estimated-compression-displacement (depth) waveform was obtained by multiplying the weight factor and the magnetic waveforms. Displacements of two large springs (with similar spring constants) within a thorax and displacements of a cardiopulmonary resuscitation training manikin were measured using the gauge to validate the accuracy of the calculated waveform. A laser-displacement detection system was used to compare the real displacement waveform and the estimated waveform. Intraclass correlation coefficients (ICCs) between the real displacement using the laser system and the estimated displacement waveforms were calculated. The estimated displacement error of the compression depth was within 2 mm (compression gauge, based on a new calculation method, provides an accurate compression depth (estimation error < 2 mm).

  13. Generation of intense, high-energy ion pulses by magnetic compression of ion rings

    International Nuclear Information System (INIS)

    Kapetanakos, C.A.

    1981-01-01

    A system based on the magnetic compression of ion rings, for generating intense (High-current), high-energy ion pulses that are guided to a target without a metallic wall or an applied external magnetic field includes a vacuum chamber; an inverse reflex tetrode for producing a hollow ion beam within the chamber; magnetic coils for producing a magnetic field, bo, along the axis of the chamber; a disc that sharpens a magnetic cusp for providing a rotational velocity to the beam and causing the beam to rotate; first and second gate coils for producing fast-rising magnetic field gates, the gates being spaced apart, each gate modifying a corresponding magnetic mirror peak (Near and far peaks) for trapping or extracting the ions from the magnetic mirror, the ions forming a ring or layer having rotational energy; a metal liner for generating by magnetic flux compression a high, time-varying magnetic field, the time-varying magnetic field progressively increasing the kinetic energy of the ions, the magnetic field from the second gate coil decreasing the far mirror peak at the end of the compression for extracting the trapped rotating ions from the confining mirror; and a disc that sharpens a magnetic half-cusp for increasing the translational velocity of the ion beam. The system utilizes the self-magnetic field of the rotating, propagating ion beam to prevent the beam from expanding radially upon extraction

  14. SSWL and BWL: finite element models of compressed magnetic field current generators

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, T.J.; Leeman, J.E.

    1976-01-01

    Documentation is presented for two new computer codes modeling the behavior of compressed magnetic field current generators. Code output results for the typical generator configurations are presented and compared to experimental results. (auth)

  15. Estimation of the iron loss in deep-sea permanent magnet motors considering seawater compressive stress.

    Science.gov (United States)

    Xu, Yongxiang; Wei, Yanyu; Zou, Jibin; Li, Jianjun; Qi, Wenjuan; Li, Yong

    2014-01-01

    Deep-sea permanent magnet motor equipped with fluid compensated pressure-tolerant system is compressed by the high pressure fluid both outside and inside. The induced stress distribution in stator core is significantly different from that in land type motor. Its effect on the magnetic properties of stator core is important for deep-sea motor designers but seldom reported. In this paper, the stress distribution in stator core, regarding the seawater compressive stress, is calculated by 2D finite element method (FEM). The effect of compressive stress on magnetic properties of electrical steel sheet, that is, permeability, BH curves, and BW curves, is also measured. Then, based on the measured magnetic properties and calculated stress distribution, the stator iron loss is estimated by stress-electromagnetics-coupling FEM. At last the estimation is verified by experiment. Both the calculated and measured results show that stator iron loss increases obviously with the seawater compressive stress.

  16. Estimation of the Iron Loss in Deep-Sea Permanent Magnet Motors considering Seawater Compressive Stress

    Directory of Open Access Journals (Sweden)

    Yongxiang Xu

    2014-01-01

    Full Text Available Deep-sea permanent magnet motor equipped with fluid compensated pressure-tolerant system is compressed by the high pressure fluid both outside and inside. The induced stress distribution in stator core is significantly different from that in land type motor. Its effect on the magnetic properties of stator core is important for deep-sea motor designers but seldom reported. In this paper, the stress distribution in stator core, regarding the seawater compressive stress, is calculated by 2D finite element method (FEM. The effect of compressive stress on magnetic properties of electrical steel sheet, that is, permeability, BH curves, and BW curves, is also measured. Then, based on the measured magnetic properties and calculated stress distribution, the stator iron loss is estimated by stress-electromagnetics-coupling FEM. At last the estimation is verified by experiment. Both the calculated and measured results show that stator iron loss increases obviously with the seawater compressive stress.

  17. The plasma formation stage in magnetic compression/magnetized target fusion (MAGO/MTF)

    International Nuclear Information System (INIS)

    Lindemuth, I.R.; Reinovsky, R.E.; Chrien, R.E.

    1996-01-01

    In early 1992, emerging governmental policy in the US and Russia began to encourage ''lab-to-lab'' interactions between the All- Russian Scientific Research Institute of Experimental Physics (VNIIEF) and the Los Alamos National Laboratory (LANL). As nuclear weapons stockpiles and design activities were being reduced, highly qualified scientists become for fundamental scientific research of interest to both nations. VNIIEF and LANL found a common interest in the technology and applications of magnetic flux compression, the technique for converting the chemical energy released by high-explosives into intense electrical pulses and intensely concentrated magnetic energy. Motivated originally to evaluate any possible defense applications of flux compression technology, the two teams worked independently for many years, essentially unaware of the others' accomplishments. But, an early US publication stimulated Soviet work, and the Soviets followed with a report of the achievement of 25 MG. During the cold war, a series of conferences on Megagauss Magnetic Field Generation and Related Topics became a forum for scientific exchange of ideas and accomplishments. Because of relationships established at the Megagauss conferences, VNIIEF and LANL were able to respond quickly to the initiatives of their respective governments. In late 1992, following the Megagauss VI conference, the two institutions agreed to combine resources to perform a series of experiments that essentially could not be performed by each institution independently. Beginning in September, 1993, the two institutions have performed eleven joint experimental campaigns, either at VNIIEF or at LANL. Megagauss- VII has become the first of the series to include papers with joint US and Russian authorship. In this paper, we review the joint LANL/VNIIEF experimental work that has relevance to a relatively unexplored approach to controlled thermonuclear fusion

  18. Pressure and compressibility of a quantum plasma in a magnetic field

    NARCIS (Netherlands)

    Suttorp, L.G.

    1993-01-01

    The equilibrium pressure tensor that occurs in the momentum balance equation for a quantum plasma in a magnetic field is shown to be anisotropic. Its relation to the pressure that follows from thermodynamics is elucidated. A general proof of the compressibility rule for a magnetized quantum plasma

  19. Large-scale vortices in compressible turbulent medium with the magnetic field

    Science.gov (United States)

    Gvaramadze, V. V.; Dimitrov, B. G.

    1990-08-01

    An averaged equation which describes the large scale vortices and Alfven waves generation in a compressible helical turbulent medium with a constant magnetic field is presented. The presence of the magnetic field leads to anisotropization of the vortex generation. Possible applications of the anisotropic vortex dynamo effect are accretion disks of compact objects.

  20. Radiopaque anastomosis marker

    International Nuclear Information System (INIS)

    Elliott, D.P.; Halseth, W.L.

    1977-01-01

    This invention relates to split ring markers fabricated in whole or in part from a radiopaque material, usually metal, having the terminal ends thereof and a medial portion formed to define eyelets by means of which said marker can be sutured to the tissue at the site of an anastomosis to provide a visual indication of its location when examined fluoroscopically

  1. Computational simulation of breast compression based on segmented breast and fibroglandular tissues on magnetic resonance images

    Energy Technology Data Exchange (ETDEWEB)

    Shih, Tzu-Ching [Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, 40402, Taiwan (China); Chen, Jeon-Hor; Nie Ke; Lin Muqing; Chang, Daniel; Nalcioglu, Orhan; Su, Min-Ying [Tu and Yuen Center for Functional Onco-Imaging and Radiological Sciences, University of California, Irvine, CA 92697 (United States); Liu Dongxu; Sun Lizhi, E-mail: shih@mail.cmu.edu.t [Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697 (United States)

    2010-07-21

    This study presents a finite element-based computational model to simulate the three-dimensional deformation of a breast and fibroglandular tissues under compression. The simulation was based on 3D MR images of the breast, and craniocaudal and mediolateral oblique compression, as used in mammography, was applied. The geometry of the whole breast and the segmented fibroglandular tissues within the breast were reconstructed using triangular meshes by using the Avizo (registered) 6.0 software package. Due to the large deformation in breast compression, a finite element model was used to simulate the nonlinear elastic tissue deformation under compression, using the MSC.Marc (registered) software package. The model was tested in four cases. The results showed a higher displacement along the compression direction compared to the other two directions. The compressed breast thickness in these four cases at a compression ratio of 60% was in the range of 5-7 cm, which is a typical range of thickness in mammography. The projection of the fibroglandular tissue mesh at a compression ratio of 60% was compared to the corresponding mammograms of two women, and they demonstrated spatially matched distributions. However, since the compression was based on magnetic resonance imaging (MRI), which has much coarser spatial resolution than the in-plane resolution of mammography, this method is unlikely to generate a synthetic mammogram close to the clinical quality. Whether this model may be used to understand the technical factors that may impact the variations in breast density needs further investigation. Since this method can be applied to simulate compression of the breast at different views and different compression levels, another possible application is to provide a tool for comparing breast images acquired using different imaging modalities--such as MRI, mammography, whole breast ultrasound and molecular imaging--that are performed using different body positions and under

  2. Use of magnetic compression based on amorphous alloys as a drive for induction linacs

    International Nuclear Information System (INIS)

    Birx, D.L.; Cook, E.G.; Hawkins, S.A.; Poor, S.E.; Reginato, L.; Schmidt, J.; Smith, M.W.

    1984-01-01

    In anticipation of current and future needs for the Particle Beam Program and other programs at the Lawrence Livermore National Laboratory, we are continuing efforts in the development of high-repetition-rate magnetic pulse compressors that use ferromagnetic metallic glasses, both in the linear and very high saturation rates. These devices are ideally suited as drivers for linear induction accelerators, where duty factor or average repetition rates (hundred of hertz) requirements exceed the parameters that can be achieved by pulse compression using spark gaps. The technique of magnetic pulse compression has been with use for several decades, but relatively recent developments in rapidly quenched magnetic metals of very thin cross sections, has led to the development of state-of-the-art magnetic pulse compressors with very high peak power, repetition rates, and reliability. This paper will describe results of recent experiments and the relevant electrical and mechanical properties of magnetic pulse compressors to achieve high efficiency and reliability

  3. Seeding magnetic fields for laser-driven flux compression in high-energy-density plasmas.

    Science.gov (United States)

    Gotchev, O V; Knauer, J P; Chang, P Y; Jang, N W; Shoup, M J; Meyerhofer, D D; Betti, R

    2009-04-01

    A compact, self-contained magnetic-seed-field generator (5 to 16 T) is the enabling technology for a novel laser-driven flux-compression scheme in laser-driven targets. A magnetized target is directly irradiated by a kilojoule or megajoule laser to compress the preseeded magnetic field to thousands of teslas. A fast (300 ns), 80 kA current pulse delivered by a portable pulsed-power system is discharged into a low-mass coil that surrounds the laser target. A >15 T target field has been demonstrated using a hot spot of a compressed target. This can lead to the ignition of massive shells imploded with low velocity-a way of reaching higher gains than is possible with conventional ICF.

  4. Phase unwinding for dictionary compression with multiple channel transmission in magnetic resonance fingerprinting.

    Science.gov (United States)

    Lattanzi, Riccardo; Zhang, Bei; Knoll, Florian; Assländer, Jakob; Cloos, Martijn A

    2018-06-01

    Magnetic Resonance Fingerprinting reconstructions can become computationally intractable with multiple transmit channels, if the B 1 + phases are included in the dictionary. We describe a general method that allows to omit the transmit phases. We show that this enables straightforward implementation of dictionary compression to further reduce the problem dimensionality. We merged the raw data of each RF source into a single k-space dataset, extracted the transceiver phases from the corresponding reconstructed images and used them to unwind the phase in each time frame. All phase-unwound time frames were combined in a single set before performing SVD-based compression. We conducted synthetic, phantom and in-vivo experiments to demonstrate the feasibility of SVD-based compression in the case of two-channel transmission. Unwinding the phases before SVD-based compression yielded artifact-free parameter maps. For fully sampled acquisitions, parameters were accurate with as few as 6 compressed time frames. SVD-based compression performed well in-vivo with highly under-sampled acquisitions using 16 compressed time frames, which reduced reconstruction time from 750 to 25min. Our method reduces the dimensions of the dictionary atoms and enables to implement any fingerprint compression strategy in the case of multiple transmit channels. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Externalized ileocolic anastomosis: case report.

    Science.gov (United States)

    Simcock, James; Kuntz, Charles A; Newman, Raquel

    2010-01-01

    A 6-year-old, spayed female Labrador retriever was presented 48 hours after an intestinal resection and anastomosis for management of a small intestinal foreign body. Abdominal ultrasound confirmed the presence of peritoneal effusion. Cytology of fluid collected by abdominocentesis revealed a large number of degenerate neutrophils with intracellular cocci. A diagnosis of septic peritonitis was made, presumably because of dehiscence of the anastomosis. Upon repeat exploratory celiotomy, the intestinal anastomosis (located 4 cm orad to the cecum) was found to be leaking intestinal contents into the abdomen. The distal ileum, cecum, and proximal colon were resected. An end-to-end, ileocolic anastomosis was performed and subsequently exteriorized into the subcutaneous space via a paramedian incision through the abdominal wall. The anastomosis was inspected daily for 4 days before it was returned to the abdomen and the subcutaneous defect was closed. Serial cytology of the peritoneal fluid, which was performed during this 4-day postoperative period, confirmed progressive resolution of peritonitis. The dog was discharged from the hospital 2 days following return of the anastomosis into the abdomen. Externalized intestinal anastomosis is used with good success in human medicine for repair of colonic injuries. In this case, externalization of the anastomosis permitted healing of the intestinal anastomosis in an environment isolated from the detrimental effects created by septic peritonitis. In addition, direct visualization of the anastomosis allowed assessment of healing. To our knowledge, this procedure has not been previously reported in companion animals.

  6. Three-dimensional density and compressible magnetic structure in solar wind turbulence

    Science.gov (United States)

    Roberts, Owen W.; Narita, Yasuhito; Escoubet, C.-Philippe

    2018-03-01

    The three-dimensional structure of both compressible and incompressible components of turbulence is investigated at proton characteristic scales in the solar wind. Measurements of the three-dimensional structure are typically difficult, since the majority of measurements are performed by a single spacecraft. However, the Cluster mission consisting of four spacecraft in a tetrahedral formation allows for a fully three-dimensional investigation of turbulence. Incompressible turbulence is investigated by using the three vector components of the magnetic field. Meanwhile compressible turbulence is investigated by considering the magnitude of the magnetic field as a proxy for the compressible fluctuations and electron density data deduced from spacecraft potential. Application of the multi-point signal resonator technique to intervals of fast and slow wind shows that both compressible and incompressible turbulence are anisotropic with respect to the mean magnetic field direction P⟂ ≫ P∥ and are sensitive to the value of the plasma beta (β; ratio of thermal to magnetic pressure) and the wind type. Moreover, the incompressible fluctuations of the fast and slow solar wind are revealed to be different with enhancements along the background magnetic field direction present in the fast wind intervals. The differences in the fast and slow wind and the implications for the presence of different wave modes in the plasma are discussed.

  7. Evaluation of the US Army Research Laboratory Squeeze 5 Magnetic Flux Compression Generator

    Science.gov (United States)

    2016-09-01

    armature cracking, high-voltage insulation , and electrical arcing. 15. SUBJECT TERMS magnetic flux compression, field diffusion, mega ampere, high... insulation and can result in arcing that robs energy from the system. Magnetic field diffusion into the conducting portions of the system can also play a...indicates a short circuit occurred internally to the device, most likely due to damaged insulation during construction. The high-voltage switch failed to

  8. Green's function of compressible Petschek-type magnetic reconnection

    International Nuclear Information System (INIS)

    Penz, Thomas; Semenov, V.S.; Ivanova, V.V.; Heyn, M.F.; Ivanov, I.B.; Biernat, H.K.

    2006-01-01

    We present a method to analyze the wave and shock structures arising from Petschek-type magnetic reconnection. Based on a time-dependent analytical approach developed by Heyn and Semenov [Phys. Plasmas 3, 2725 (1996)] and Semenov et al. [Phys. Plasmas 11, 62 (2004)], we calculate the perturbations caused by a delta function-shaped reconnection electric field, which allows us to achieve a representation of the plasma variables in the form of Green's functions. Different configurations for the initial conditions are considered. In the case of symmetric, antiparallel magnetic fields and symmetric plasma density, the well-known structure of an Alfven discontinuity, a fast body wave, a slow shock, a slow wave, and a tube wave occurs. In the case of asymmetric, antiparallel magnetic fields, additionally surface waves are found. We also discuss the case of symmetric, antiparallel magnetic fields and asymmetric densities, which leads to a faster propagation in the lower half plane, causing side waves forming a Mach cone in the upper half plane. Complex effects like anisotropic propagation characteristics, intrinsic wave coupling, and the generation of different nonlinear and linear wave modes in a finite β plasma are retained. The temporal evolution of these wave and shock structures is shown

  9. Neutron measurements in the FRX-C/LSM magnetic compression experiment

    International Nuclear Information System (INIS)

    Chrien, R.E.; Baron, M.H.

    1989-01-01

    Neutron measurements are being pursued as an ion temperature diagnostic in the FRX-C/LSM Magnetic Compression Experiment. One can easily see that the d-d neutron emission is a sensitive measure of ion heating during adiabatic magnetic compression of FRCs. The reaction rate may be written as R = (1/2) n N left-angle σv right-angle, where n and N are the deuterium density and inventory. The fusion reactivity varies as left-angle σv right-angle ∝ T 5.6 for T ≅ 1 keV. For adiabatic compression, n ∝ B 1.2 and T ∝ B 0.8 so R ∝ B 5.7 in the absence of losses. The neutron yield is also sensitive to the time duration that the plasma remains near its peak temperature. 4 refs., 4 figs

  10. Magnetic resonance imaging in cervical spinal cord compression

    Directory of Open Access Journals (Sweden)

    Giovanni Giammona

    1993-09-01

    Full Text Available In patients with cervical spondylotic myelopathy MRI sometimes shows increased signal intensity zones on the T2-weighted images. It has been suggested that these findings carry prognostic significance. We studied 56 subjects with cervical spinal cord compression. Twelve patients showed an increased signal intensity (21.4% and a prevalence of narrowing of the AP-diameter (62% vs 24%. Furthemore, in this group, there was evidence of a longer mean duration of the symptoms and, in most of the patients, of more serious clinical conditions. The importance of these predisposing factors remains, however, to be clarified since they are also present in some patients without the increased signal intensity.

  11. The role of fluid compression in energy conversion and particle energization during magnetic reconnection

    Science.gov (United States)

    Li, X.; Guo, F.; Li, G.; Li, H.

    2016-12-01

    Theories of particle transport and acceleration have shown that fluid compression is the leading mechanism for particle acceleration and plasma energization. However, the role of compression in particle acceleration during magnetic reconnection is unclear. We use two approaches to study this issue. First, using fully kinetic simulations, we quantitatively calculate the effect of compression in energy conversion and particle energization during magnetic reconnection for a range of plasma beta and guide field. We show that compression has an important contribution for the energy conversion between the bulk kinetic energy and the internal energy when the guide field is smaller than the reconnecting component. Based on this result, we then study the large-scale reconnection acceleration by solving the Parker's transport equation in a background reconnecting flow provided by MHD simulations. Due to the compression effect, the simulations suggest fast particle acceleration to high energies in the reconnection layer. This study clarifies the nature of particle acceleration in reconnection layer, and may be important to understand particle acceleration and plasma energization during solar flares.

  12. Magnetic compression ostomy for simple tube colostomy in rats--magnacolostomy.

    Science.gov (United States)

    Uygun, Ibrahim; Okur, Mehmet H; Arayici, Yilmaz; Keles, Aysenur; Ozturk, Hayrettin; Otcu, Selcuk

    2012-01-01

    Magnetic compression anastomoses (magnamosis) have been previously described for gastrointestinal, biliary, urinary, and vascular anastomoses. Objectives. Herein, the authors report the creation of a magnetic compression colostomy (magnacolostomy) using a simple technique in rats. Animals were randomized into two groups (n = 8, each): a magnetic colostomy (MC) group and a control surgical tube colostomy (SC) group. In the MC group, the first magnetic ball (3 mm) was rectally introduced into the rat colon. The second magnetic ball (4 mm) was placed subcutaneously into the left quadrant, and the two magnetic balls strongly coupled. On postoperative day 20 for the MC group and postoperative day 10 in the SC group, the rats were sacrificed and the colostomies evaluated macroscopically, histopathologically, and for mechanical burst testing. From the macroscopic evaluation, two rats failed to form the colostomy canal due to colostomy catheter and magnetic ball removal. In the remaining rats, evidence of complications were not observed. Two rats in the MC group displayed mild adhesion and all rats in the SC group displayed moderate adhesion. No significant differences between the burst pressures were observed. However, a significant difference (p colostomy procedures such as antegrade continence enemas, percutaneous endoscopic, and colostomy/cecostomy in humans.

  13. Emittance preservation during bunch compression with a magnetized beam

    Energy Technology Data Exchange (ETDEWEB)

    Stratakis, Diktys [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-09-02

    The deleterious effects of coherent synchrotron radiation (CSR) on the phase-space and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. In this paper, we present a simple method to preserve the beam emittance by means of using magnetized beams that exhibit a large aspect ratio on their transverse dimensions. The concept is based on combining a finite solenoid field where the beam is generated together with a special optics adapter. Numerical simulations of this new type of beam source show that the induced phase-space density growth can be notably suppressed to less than 1% for any bunch charge. This work elucidates the key parameters that are needed for emittance preservation, such as the required field and aspect ratio for a given bunch charge.

  14. Emittance preservation during bunch compression with a magnetized beam

    Energy Technology Data Exchange (ETDEWEB)

    Stratakis, Diktys

    2016-03-01

    The deleterious effects of coherent synchrotron radiation (CSR) on the phase-space and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. In this paper, we present a simple method to preserve the beam emittance by means of using magnetized beams that exhibit a large aspect ratio on their transverse dimensions. The concept is based in combining a finite solenoid field where the beam is generated with a special optics adapter. Numerical simulations of this new type of beam source show that the induced phase-space density growth from CSR can be notably suppressed to less than 1% for any bunch charge. This work elucidates the key parameters that are needed for emittance preservation, such as the required field and aspect ratio for a given bunch charge.

  15. Vascular anastomosis by Argon Laser

    International Nuclear Information System (INIS)

    Gomes, O.M.; Macruz, R.; Armelin, E.; Brum, J.M.G.; Ribeiro, M.P.; Mnitentog, J.; Verginelli, G.; Pileggi, F.; Zerbini, E.J.

    1982-01-01

    Twenty four mongrel dogs, wheighing 13 to 24 kilograms were studied. After anesthesia, intubation and controlled ventilation, they were submitted to three types of vascular anastomosis: Group I - eight dogs with saphenous vein inter-carotid arteries by-pass: Group II - eight dogs with left mammary artery - left anterior descending coronary artery by-pass; Group III - eight dogs with venovenous anastomosis. In all groups 0.8 to 15 watts of Argon Laser power was applied to a total time of 90 to 300 seconds. The lower power for venovenous anastomosis and the greater for the arterial ones. The mean valves of resistence of the Laser anastomosis to pressure induced rupture was 730 mmHg in the immediate post operative study, and superior to 2.500 mmHg 30 days after. No signs of occlusion was demonstrated at the anastomosis sites by the angiographic and anathomo-patological study performed. (Author) [pt

  16. Local System Matrix Compression for Efficient Reconstruction in Magnetic Particle Imaging

    Directory of Open Access Journals (Sweden)

    T. Knopp

    2015-01-01

    Full Text Available Magnetic particle imaging (MPI is a quantitative method for determining the spatial distribution of magnetic nanoparticles, which can be used as tracers for cardiovascular imaging. For reconstructing a spatial map of the particle distribution, the system matrix describing the magnetic particle imaging equation has to be known. Due to the complex dynamic behavior of the magnetic particles, the system matrix is commonly measured in a calibration procedure. In order to speed up the reconstruction process, recently, a matrix compression technique has been proposed that makes use of a basis transformation in order to compress the MPI system matrix. By thresholding the resulting matrix and storing the remaining entries in compressed row storage format, only a fraction of the data has to be processed when reconstructing the particle distribution. In the present work, it is shown that the image quality of the algorithm can be considerably improved by using a local threshold for each matrix row instead of a global threshold for the entire system matrix.

  17. Effect of aggregates on the magnetization property of ferrofluids: A model of gaslike compression

    Directory of Open Access Journals (Sweden)

    Jian Li, Yan Huang, Xiaodong Liu, Yueqing Lin, Lang Bai and Qiang Li

    2007-01-01

    Full Text Available The effect of field-induced aggregation of particles on the magnetization property of ferrofluids is investigated. From the viewpoint of energy, magnetizability of ferrofluids is more complicated than predicted by Langevin theory because the aggregation, i.e., the transition of ferrofluid microstructure, would consume the energy of the applied magnetic field. For calculating the effect of aggregates on the magnetization of ferrofluids, a model of gaslike compression (MGC is proposed to simulate the evolution of the aggregate structure. In this model, the field-induced colloidal particles aggregating in ferrofluids is equivalent to the "gas of the particles" being compressed by the applied magnetic field. The entropy change of the ferrofluid microstructure is proportional to the particle volume fraction in field-induced aggregates phivH. On the basis of the known behavior of ferrofluid magnetization and the aggregate structure determined from the present experiments, phivH is obtained and found to depend on the aggregating characteristic parameter of ferrofluid particles γ in addition to the particle volume fraction in ferrofluids phiv and the strength of applied magnetic field H. The effect of the nonmagnetic surface layer of ferrofluid particles is also studied. The theory of MGC conforms to our experimental results better than Langevin theory.

  18. Cerebral magnetic resonance imaging of compressed air divers in diving accidents.

    Science.gov (United States)

    Gao, G K; Wu, D; Yang, Y; Yu, T; Xue, J; Wang, X; Jiang, Y P

    2009-01-01

    To investigate the characteristics of the cerebral magnetic resonance imaging (MRI) of compressed air divers in diving accidents, we conducted an observational case series study. MRI of brain were examined and analysed on seven cases compressed air divers complicated with cerebral arterial gas embolism CAGE. There were some characteristics of cerebral injury: (1) Multiple lesions; (2) larger size; (3) Susceptible to parietal and frontal lobe; (4) Both cortical grey matter and subcortical white matter can be affected; (5) Cerebellum is also the target of air embolism. The MRI of brain is an sensitive method for detecting cerebral lesions in compressed air divers in diving accidents. The MRI should be finished on divers in diving accidents within 5 days.

  19. Magnetic resonance imaging of malignant extradural tumors with acute spinal cord compression

    International Nuclear Information System (INIS)

    Lien, H.H.; Blomlie, V.; Heimdal, K.; Norwegian Radium Hospital, Oslo; Norwegian Radium Hospital, Oslo

    1990-01-01

    Thirty-six cancer patients with extradural spinal metastatic disease and acute symptoms of spinal cord compression underwent magnetic resonance (MR) imaging at 1.5 T. Cord involvement was found in all 36, 7 of whom had lesions at 2 different sites. Vertebral metastases in addition to those corresponding to the cord compressions were detected in 27 patients, and 18 of these had widespread deposits. MR displayed the extent of the tumors in the craniocaudal and lateral directions. The ability to identify multiple sites of cord and vertebral involvement and to delineate tumor accurately makes MR the examination of choice in cancer patients with suspected spinal cord compression. It obviates the need for myelography and postmyelography CT in this group of patients. (orig.)

  20. Investigation of shock compressed plasma parameters by interaction with magnetic field

    International Nuclear Information System (INIS)

    Dudin, S. V.; Fortov, V. E.; Gryaznov, V. K.; Mintsev, V. B.; Shilkin, N. S.; Ushnurtsev, A. E.

    1998-01-01

    The Hall effect parameters in shock compressed air, helium and xenon have been estimated and results of experiments with air and helium plasma are presented. Explosively driven shock tubes were used for the generation of strong shock waves. To obtain magnetic field a solenoid was winded over the shock tube. Calculations of dense shock compressed plasma parameters were carried out to plan the experiments. In the experiments with the magnetic field of ∼5 T it was found, that air plasma slug was significantly heated by the whirlwind electrical field. The reflected shock waves technique was used in the experiments with helium. Results on measurements of electrical conductivity and electron concentration of helium are presented

  1. Manipulating Electromagnetic Waves in Magnetized Plasmas: Compression, Frequency Shifting, and Release

    International Nuclear Information System (INIS)

    Avitzour, Yoav; Shvets, Gennady

    2008-01-01

    A new approach to manipulating the duration and frequency of microwave pulses using magnetized plasmas is demonstrated. The plasma accomplishes two functions: (i) slowing down and spatially compressing the incident wave, and (ii) modifying the propagation properties (group velocity and frequency) of the wave in the plasma during a uniform in space adiabatic in time variation of the magnitude and/or direction of the magnetic field. The increase in the group velocity results in the shortening of the temporal pulse duration. Depending on the plasma parameters, the frequency of the outgoing compressed pulse can either change or remain unchanged. Such dynamic manipulation of radiation in plasma opens new avenues for manipulating high power microwave pulses

  2. Magnetic resonance imaging of vascular compression in trigeminal neuralgia and hemifacial spasms

    International Nuclear Information System (INIS)

    Nagaseki, Yoshishige; Horikoshi, Tohru; Omata, Tomohiro; Sugita, Masao; Nukui, Hideaki; Sakamoto, Hajime; Kumagai, Hiroshi; Sasaki, Hideo; Tsuji, Reizou.

    1991-01-01

    We show how neurosurgical planning can benefit from the better visualization of the precise vascular compression of the nerve provided by the oblique-sagittal and gradient-echo method (OS-GR image) using magnetic resonance images (MRI). The scans of 3 patients with trigeminal neuralgia (TN) and of 15 with hemifacial spasm (HFS) were analyzed for the presence and appearance of the vascular compression of the nerves. Imaging sequences consisted of an OS-GR image (TR/TE: 200/20, 3-mm-thick slice) cut along each nerve shown by the axial view, which was scanned at the angle of 105 degrees taken between the dorsal line of the brain stem and the line corresponding to the pontomedullary junction. In the OS-GR images of the TN's, the vascular compressions of the root entry zone (REZ) of the trigeminal nerve were well visualized as high-intensity lines in the 2 cases whose vessels were confirmed intraoperatively. In the other case, with atypical facial pain, vascular compression was confirmed at the rostral distal site on the fifth nerve, apart from the REZ. In the 15 cases of HFS, twelve OS-GR images (80%) demonstrated vascular compressions at the REZ of the facial nerves from the direction of the caudoventral side. During the surgery for these 12 cases, in 11 cases (excepting the 1 case whose facial nerve was not compressed by any vessels), vascular compressions were confirmed corresponding to the findings of the OS-GR images. Among the 10 OS-GR images on the non-affected side, two false-positive findings were visualized. It is concluded that OS-GR images obtained by means of MRI may serve as a useful planning aid prior to microvascular decompression for cases of TN and HFS. (author)

  3. Longitudinal propagation of nonlinear surface Alfven waves at a magnetic interface in a compressible atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Ruderman, M S

    1988-08-01

    Nonlinear Alfven surface wave propagation at a magnetic interface in a compressible fluid is considered. It is supposed that the magnetic field directions at both sides of the interface and the direction of wave propagation coincide. The equation governing time-evolution of nonlinear small-amplitude waves is derived by the method of multiscale expansions. This equation is similar to the equation for nonlinear Alfven surface waves in an incompressible fluid derived previously. The numerical solution of the equation shows that a sinusoidal disturbance overturns, i.e. infinite gradients arise.

  4. Experimental and theoretical study of helical explosive electrical current generators with magnetic field compression

    International Nuclear Information System (INIS)

    Antoni, Bernard; Nazet, Christian.

    1975-07-01

    A generator of electrical energy in which magnetic field compression is achieved by a solid explosive is described. The magnetic flux losses have been calculated for generators of various configurations by the skin depth concept. Calculations take the Joule heating of conductors into account. In helical generators the magnetic flux losses are higher than those calculated by considering diffusion only. Additional losses approximately as important as diffusion losses have already been observed elsewhere on similar devices. Detailed calculations of the motion of the explosively driven inner conductor show that losses come from the jumps encountered by sliding contact moving along the helix. The jumps are caused by little geometrical defects and the consequence on losses is strongly dependent on current intensity. The jumps decrease when the pitch of helix increases. The jumps are detrimental to the efficient use of the explosive energy. With helical generators only 5% of the energy is transferred into magnetic energy [fr

  5. Splenorenal shunt via magnetic compression technique: a feasibility study in canine and cadaver.

    Science.gov (United States)

    Xue, Fei; Li, Jianpeng; Lu, Jianwen; Zhu, Haoyang; Liu, Wenyan; Zhang, Hongke; Yang, Huan; Guo, Hongchang; Lv, Yi

    2016-12-01

    The concept of magnetic compression technique (MCT) has been accepted by surgeons to solve a variety of surgical problems. In this study, we attempted to explore the feasibility of a splenorenal shunt using MCT in canine and cadaver. The diameters of the splenic vein (SV), the left renal vein (LRV), and the vertical interval between them, were measured in computer tomography (CT) images obtained from 30 patients with portal hypertension and in 20 adult cadavers. The magnetic devices used for the splenorenal shunt were then manufactured based on the anatomic parameters measured above. The observation of the anatomical structure showed there were no special structural tissues or any important organs between SV and LRV. Then the magnetic compression splenorenal shunt procedure was performed in three dogs and five cadavers. Seven days later, the necrotic tissue between the two magnets was shed and the magnets were removed with the anchor wire. The feasibility of splenorenal shunt via MCT was successfully shown in both canine and cadaver, thus providing a theoretical support for future clinical application.

  6. Model for field-induced reorientation strain in magnetic shape memory alloy with tensile and compressive loads

    International Nuclear Information System (INIS)

    Zhu Yuping; Dui Guansuo

    2008-01-01

    A model based on the micromechanical and the thermodynamic theory is presented for field-induced martensite reorientation in magnetic shape memory alloy (MSMA) single crystals. The influence of variants morphology and the material property to constitutive behavior is considered. The nonlinear and hysteretic strain and magnetization response of MSMA are investigated for two main loading cases, namely the magnetic field-induced reorientation of variants under constant compressive stress and tensile stress. The predicted results have shown that increasing tensile loading reduces the required field for actuation, while increasing compressive loads result in the required magnetic field growing considerably. It is helpful to design the intelligent composite with MSMA fibers

  7. The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection

    Science.gov (United States)

    Li, Xiaocan; Guo, Fan; Li, Hui; Birn, Joachim

    2018-03-01

    Particle acceleration in space and astrophysical reconnection sites is an important unsolved problem in studies of magnetic reconnection. Earlier kinetic simulations have identified several acceleration mechanisms that are associated with particle drift motions. Here, we show that, for sufficiently large systems, the energization processes due to particle drift motions can be described as fluid compression and shear, and that the shear energization is proportional to the pressure anisotropy of energetic particles. By analyzing results from fully kinetic simulations, we show that the compression energization dominates the acceleration of high-energy particles in reconnection with a weak guide field, and the compression and shear effects are comparable when the guide field is 50% of the reconnecting component. Spatial distributions of those energization effects reveal that reconnection exhausts, contracting islands, and island-merging regions are the three most important regions for compression and shear acceleration. This study connects particle energization by particle guiding-center drift motions with that due to background fluid motions, as in the energetic particle transport theory. It provides foundations for building particle transport models for large-scale reconnection acceleration such as those in solar flares.

  8. Magnetic resonance imaging validation of pituitary gland compression and distortion by typical sellar pathology.

    Science.gov (United States)

    Cho, Charles H; Barkhoudarian, Garni; Hsu, Liangge; Bi, Wenya Linda; Zamani, Amir A; Laws, Edward R

    2013-12-01

    Identification of the normal pituitary gland is an important component of presurgical planning, defining many aspects of the surgical approach and facilitating normal gland preservation. Magnetic resonance imaging is a proven imaging modality for optimal soft-tissue contrast discrimination in the brain. This study is designed to validate the accuracy of localization of the normal pituitary gland with MRI in a cohort of surgical patients with pituitary mass lesions, and to evaluate for correlation between presurgical pituitary hormone values and pituitary gland characteristics on neuroimaging. Fifty-eight consecutive patients with pituitary mass lesions were included in the study. Anterior pituitary hormone levels were measured preoperatively in all patients. Video recordings from the endoscopic or microscopic surgical procedures were available for evaluation in 47 cases. Intraoperative identification of the normal gland was possible in 43 of 58 cases. Retrospective MR images were reviewed in a blinded fashion for the 43 cases, emphasizing the position of the normal gland and the extent of compression and displacement by the lesion. There was excellent agreement between imaging and surgery in 84% of the cases for normal gland localization, and in 70% for compression or noncompression of the normal gland. There was no consistent correlation between preoperative pituitary dysfunction and pituitary gland localization on imaging, gland identification during surgery, or pituitary gland compression. Magnetic resonance imaging proved to be accurate in identifying the normal gland in patients with pituitary mass lesions, and was useful for preoperative surgical planning.

  9. Fast magnetic reconstruction of the portal vein with allogeneic blood vessels in canines.

    Science.gov (United States)

    Wang, Shan-Pei; Yan, Xiao-Peng; Xue, Fei; Dong, Ding-Hui; Zhang, Xu-Feng; Ma, Feng; Wang, Hao-Hua; Lv, Yi

    2015-06-01

    The resection and reconstruction of large vessels, including the portal vein, are frequently needed in tumor resection. Warm ischemia before reconstruction might have deleterious effects on the function of some vital organs and therefore, how to reconstruct the vessels quickly after resection is extremely important. The present study was to introduce a new type of magnetic compression anastomosis (MCA) device to establish a quick non-suture anastomosis of the portal vein after resection in canines. The new MCA device consists of a pair of titanium alloy and neodymium-ferrum-boron magnet (Ti-NdFeB) composite rings. The NdFeB magnetic ring as a core of the device was hermetically sealed inside the biomedical titanium alloy case. Twelve canines were divided into two groups: a MCA group in which the end-to-end anastomoses was made with a new device after resection in the portal vein and a traditional manual suture (TMS) group consisted of 6 canines. The anastomosis time, anastomotic patency and quality were investigated at week 24 postoperatively. The portal vein was reconstructed successfully in all of the animals and they all survived. The duration of portal vein anastomosis was significantly shorter in the MCA group than in the TMS group (8.16+/-1.25 vs 36.24+/-2.17 min, PNdFeB composite MCA device was applicable in reconstruction of large vessels after resection. This device was easy to use and the anastomosis was functionally better than the traditional sutured anastomosis.

  10. Balanced sparse model for tight frames in compressed sensing magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Yunsong Liu

    Full Text Available Compressed sensing has shown to be promising to accelerate magnetic resonance imaging. In this new technology, magnetic resonance images are usually reconstructed by enforcing its sparsity in sparse image reconstruction models, including both synthesis and analysis models. The synthesis model assumes that an image is a sparse combination of atom signals while the analysis model assumes that an image is sparse after the application of an analysis operator. Balanced model is a new sparse model that bridges analysis and synthesis models by introducing a penalty term on the distance of frame coefficients to the range of the analysis operator. In this paper, we study the performance of the balanced model in tight frame based compressed sensing magnetic resonance imaging and propose a new efficient numerical algorithm to solve the optimization problem. By tuning the balancing parameter, the new model achieves solutions of three models. It is found that the balanced model has a comparable performance with the analysis model. Besides, both of them achieve better results than the synthesis model no matter what value the balancing parameter is. Experiment shows that our proposed numerical algorithm constrained split augmented Lagrangian shrinkage algorithm for balanced model (C-SALSA-B converges faster than previously proposed algorithms accelerated proximal algorithm (APG and alternating directional method of multipliers for balanced model (ADMM-B.

  11. Explosive magnetic flux compression plate generators as fast high-energy power sources

    International Nuclear Information System (INIS)

    Caird, R.S.; Erickson, D.J.; Garn, W.B.; Fowler, C.M.

    1976-01-01

    A type of explosive driven generator, called a plate generator, is described. It is capable of delivering electrical energies in the MJ range at TW power levels. Plane wave detonated explosive systems accelerate two large-area metal plates to high opposing velocities. An initial magnetic field is compressed and the flux transferred to an external load. The characteristics of the plate generator are described and compared with those of other types of generators. Methods of load matching are discussed. The results of several high-power experiments are also given

  12. New anastomosis technique for (laparoscopic) instrumental small-diameter anastomosis.

    Science.gov (United States)

    Schöb, O; Schmid, R; Schlumpf, R; Klotz, H P; Spiess, M; Largiadèr, F

    1995-04-01

    This study presents a new technique for visceral anastomosis. The principle consists of connecting the two parts to be anastomosed around a reabsorbable stent which is transluminally introduced into small-diameter viscus, where it is fixed. Advancing a larger tube along the axis of the machine, the larger, perforated viscus is inverted and pulled over the stent, and finally a rubber band pops off the machine endoluminally in order to fix the intestinal walls in seroserosal contact onto the stent. To evaluate this "micro" anastomosis, a biliary bypass (choledochojejunostomy and roux-en-y-loop) was performed in ten pigs. Nine of ten animals showed biliary bypass with good runoff in contrast radiography and completely reabsorbed stent after a 3-month follow-up. Weight gain, bilirubin, and alkaline phosphatase were normal. This technology demonstrates a safe and quick way to perform instrumental "micro" anastomosis without remnant foreign material.

  13. Compressive effect of the magnetic field on the positron range in commonly used positron emitters simulated using Geant4

    Science.gov (United States)

    Li, Chong; Cao, Xingzhong; Liu, Fuyan; Tang, Haohui; Zhang, Zhiming; Wang, Baoyi; Wei, Long

    2017-11-01

    The compressive effect of a magnetic field on the positron range from commonly used positron emitters in PET (Positron Emission Tomography) was simulated using the Geant4 toolkit with H2O as the environmental material. The compression of the positron range, which was different in the directions parallel and perpendicular to the magnetic field, showed finite final variation of relative change rate versus the magnetic field. The variation greatly depended on the positron-emission energy spectrum in the same medium. Furthermore, the volume of the positron annihilation point was dramatically compressed as the magnetic field was set in the range of 3-6T. It was more prominent for 82Rb , which is generally used as a positron source in PET technology.

  14. Generation and compression of a target plasma for magnetized target fusion

    International Nuclear Information System (INIS)

    Kirkpatrick, R.C.; Lindemuth, I.R.; Sheehey, P.T.

    1998-01-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Magnetized target fusion (MTF) is intermediate between the two very different approaches to fusion: inertial and magnetic confinement fusion (ICF and MCF). Results from collaboration with a Russian MTF team on their MAGO experiments suggest they have a target plasma suitable for compression to provide an MTF proof of principle. This LDRD project had tow main objectives: first, to provide a computational basis for experimental investigation of an alternative MTF plasma, and second to explore the physics and computational needs for a continuing program. Secondary objectives included analytic and computational support for MTF experiments. The first objective was fulfilled. The second main objective has several facets to be described in the body of this report. Finally, the authors have developed tools for analyzing data collected on the MAGO and LDRD experiments, and have tested them on limited MAGO data

  15. Compressive strength and magnetic properties of calcium silicate-zirconia-iron (III) oxide composite cements

    Science.gov (United States)

    Ridzwan, Hendrie Johann Muhamad; Shamsudin, Roslinda; Ismail, Hamisah; Yusof, Mohd Reusmaazran; Hamid, Muhammad Azmi Abdul; Awang, Rozidawati Binti

    2018-04-01

    In this study, ZrO2 microparticles and γ-Fe2O3 nanoparticles have been added into calcium silicate based cements. The purpose of this experiment was to investigate the compressive strength and magnetic properties of the prepared composite cement. Calcium silicate (CAS) powder was prepared by hydrothermal method. SiO2 and CaO obtained from rice husk ash and limestone respectively were autoclaved at 135 °C for 8 h and sintered at 950°C to obtain CAS powder. SiO2:CaO ratio was set at 45:55. CAS/ZrO2 sample were prepared with varying ZrO2 microparticles concentrations by 0-40 wt. %. Compressive strength value of CAS/ZrO2 cements range from 1.44 to 2.44 MPa. CAS/ZrO2/γ-Fe2O3 sample with 40 wt. % ZrO2 were prepared with varying γ-Fe2O3 nanoparticles concentrations (1-5 wt. %). The additions of γ-Fe2O3 nanoparticles showed up to twofold increase in the compressive strength of the cement. X-Ray diffraction (XRD) results confirm the formation of mixed phases in the produced composite cements. Vibrating sample magnetometer (VSM) analysis revealed that the ferromagnetic behaviour has been observed in CAS/ZrO2/γ-Fe2O3 composite cements.

  16. Inductively Driven, 3D Liner Compression of a Magnetized Plasma to Megabar Energy Densities

    Energy Technology Data Exchange (ETDEWEB)

    Slough, John [MSNW LLC, Redmond, WA (United States)

    2015-02-01

    To take advantage of the smaller scale, higher density regime of fusion an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. What is proposed is a more flexible metallic liner compression scheme that minimizes the kinetic energy required to reach fusion. It is believed that it is possible to accomplish this at sub-megajoule energies. This however will require operation at very small scale. To have a realistic hope of inexpensive, repetitive operation, it is essential to have the liner kinetic energy under a megajoule which allows for the survivability of the vacuum and power systems. At small scale the implosion speed must be reasonably fast to maintain the magnetized plasma (FRC) equilibrium during compression. For limited liner kinetic energy, it becomes clear that the thinnest liner imploded to the smallest radius consistent with the requirements for FRC equilibrium lifetime is desired. The proposed work is directed toward accomplishing this goal. Typically an axial (Z) current is employed for liner compression. There are however several advantages to using a θ-pinch coil. With the θ-pinch the liner currents are inductively driven which greatly simplifies the apparatus and vacuum system, and avoids difficulties with the post implosion vacuum integrity. With fractional flux leakage, the foil liner automatically provides for the seed axial compression field. To achieve it with optimal switching techniques, and at an accelerated pace however will require additional funding. This extra expense is well justified as the compression technique that will be enabled by this funding is unique in the ability to implode individual segments of the liner at different times. This is highly advantageous as the liner can be imploded in a manner that maximizes the energy transfer to the FRC. Production of shaped liner implosions for additional axial compression can thus be readily accomplished with the modified power

  17. Magnetic fingerprint of individual Fe4 molecular magnets under compression by a scanning tunnelling microscope

    Science.gov (United States)

    Burgess, Jacob A. J.; Malavolti, Luigi; Lanzilotto, Valeria; Mannini, Matteo; Yan, Shichao; Ninova, Silviya; Totti, Federico; Rolf-Pissarczyk, Steffen; Cornia, Andrea; Sessoli, Roberta; Loth, Sebastian

    2015-09-01

    Single-molecule magnets (SMMs) present a promising avenue to develop spintronic technologies. Addressing individual molecules with electrical leads in SMM-based spintronic devices remains a ubiquitous challenge: interactions with metallic electrodes can drastically modify the SMM's properties by charge transfer or through changes in the molecular structure. Here, we probe electrical transport through individual Fe4 SMMs using a scanning tunnelling microscope at 0.5 K. Correlation of topographic and spectroscopic information permits identification of the spin excitation fingerprint of intact Fe4 molecules. Building from this, we find that the exchange coupling strength within the molecule's magnetic core is significantly enhanced. First-principles calculations support the conclusion that this is the result of confinement of the molecule in the two-contact junction formed by the microscope tip and the sample surface.

  18. Impact of compressibility and a guide field on Fermi acceleration during magnetic island coalescence

    Science.gov (United States)

    Montag, Peter; Egedal, Jan; Lichko, Emily; Wetherton, Blake

    2017-10-01

    Previous work has shown that Fermi acceleration can be an effective heating mechanism during magnetic island coalescence, where electrons may undergo repeated reflections as the magnetic field lines contract. This energization has the potential to account for the power-law distributions of particle energy inferred from observations of solar flares. Here, we develop a generalized framework for the analysis of Fermi acceleration that can incorporate the effects of compressibility and non-uniformity along field lines, which have commonly been neglected in previous treatments of the problem. Applying this framework to the simplified case of the uniform flux tube allows us to find both the power-law scaling of the distribution function and the rate at which the power-law behavior develops. We find that a guide magnetic field of order unity effectively suppresses the development of power-law distributions. The work was supported by NASA Grant No. NNX14AC68G, NSF GEM Grant No. 1405166, NSF Award 1404166, and NASA Award NNX15AJ73G.

  19. Densimetry in compressed fluids by combining hydrostatic weighing and magnetic levitation

    International Nuclear Information System (INIS)

    Masui, R.; Haynes, W.M.; Chang, R.F.; Davis, H.A.; Sengers, J.M.H.L.

    1984-01-01

    A magnetic suspension densimeter is described that has been built for measuring the density of compressed liquids at pressures up to 15 MPa in the temperature range 20 0 --200 0 C with an uncertainty of 0.1%. The densimeter combines the principle of magnetic levitation of a buoy with that of liquid density determination by hydrostatic weighing. To accomplish this, the support coil is suspended from an electronic balance, and the balance readings are recorded (1) with the buoy at rest, and (2) with the buoy in magnetic suspension. Details are given of the construction of the cell, coil, buoy, and thermostat. The procedure is described by which cell and buoy are aligned so that the suspended buoy does not touch the cell wall. Test data on the densities of seven different liquids were obtained at room temperature. They agree with reliable literature values to within 0.1%. In a separate experiment, the bulk thermal expansion coefficient of the buoy material was determined. This experiment and its results are also given here

  20. Implementing and diagnosing magnetic flux compression on the Z pulsed power accelerator

    Energy Technology Data Exchange (ETDEWEB)

    McBride, Ryan D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bliss, David E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gomez, Matthew R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hansen, Stephanie B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Matthew R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jennings, Christopher Ashley [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Slutz, Stephen A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rovang, Dean C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Knapp, Patrick F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schmit, Paul F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Awe, Thomas James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hess, M. H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lemke, Raymond W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dolan, D. H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lamppa, Derek C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jobe, Marc Ronald Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fang, Lu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hahn, Kelly D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chandler, Gordon A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cooper, Gary Wayne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ruiz, Carlos L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Maurer, A. J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robertson, Grafton Kincannon [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cuneo, Michael E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sinars, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tomlinson, Kurt [General Atomics, San Diego, CA (United States); Smith, Gary [General Atomics, San Diego, CA (United States); Paguio, Reny [General Atomics, San Diego, CA (United States); Intrator, Tom [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Weber, Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Greenly, John [Cornell Univ., Ithaca, NY (United States)

    2015-11-01

    We report on the progress made to date for a Laboratory Directed Research and Development (LDRD) project aimed at diagnosing magnetic flux compression on the Z pulsed-power accelerator (0-20 MA in 100 ns). Each experiment consisted of an initially solid Be or Al liner (cylindrical tube), which was imploded using the Z accelerator's drive current (0-20 MA in 100 ns). The imploding liner compresses a 10-T axial seed field, B z ( 0 ) , supplied by an independently driven Helmholtz coil pair. Assuming perfect flux conservation, the axial field amplification should be well described by B z ( t ) = B z ( 0 ) x [ R ( 0 ) / R ( t )] 2 , where R is the liner's inner surface radius. With perfect flux conservation, B z ( t ) and dB z / dt values exceeding 10 4 T and 10 12 T/s, respectively, are expected. These large values, the diminishing liner volume, and the harsh environment on Z, make it particularly challenging to measure these fields. We report on our latest efforts to do so using three primary techniques: (1) micro B-dot probes to measure the fringe fields associated with flux compression, (2) streaked visible Zeeman absorption spectroscopy, and (3) fiber-based Faraday rotation. We also mention two new techniques that make use of the neutron diagnostics suite on Z. These techniques were not developed under this LDRD, but they could influence how we prioritize our efforts to diagnose magnetic flux compression on Z in the future. The first technique is based on the yield ratio of secondary DT to primary DD reactions. The second technique makes use of the secondary DT neutron time-of-flight energy spectra. Both of these techniques have been used successfully to infer the degree of magnetization at stagnation in fully integrated Magnetized Liner Inertial Fusion (MagLIF) experiments on Z [P. F. Schmit et al. , Phys. Rev. Lett. 113 , 155004 (2014); P. F. Knapp et al. , Phys. Plasmas, 22 , 056312 (2015)]. Finally, we present some recent developments for designing

  1. Feasibility of intermittent pneumatic compression for venous thromboembolism prophylaxis during magnetic resonance imaging-guided interventions

    Energy Technology Data Exchange (ETDEWEB)

    Maybody, Majid, E-mail: maybodym@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Taslakian, Bedros, E-mail: bt05@aub.edu.lb [Department of Diagnostic Radiology, American University of Beirut Medical Center, Riad El-Solh, 1107 2020 Beirut (Lebanon); Durack, Jeremy C., E-mail: durackj@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Kaye, Elena A., E-mail: kayee@mskcc.org [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Erinjeri, Joseph P., E-mail: erinjerj@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Srimathveeravalli, Govindarajan, E-mail: srimaths@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Solomon, Stephen B., E-mail: solomons@mskcc.org [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States)

    2015-04-15

    Highlights: •The controller of a standard SCD is labeled as an “MR-unsafe”. •No commercially available “MR-safe” SCDs. •Standard SCDs can be used in iMRI by placing the device outside the MRI scanner room. •Using serial extension tubing did not cause device failure. -- Abstract: Purpose: Venous thromboembolism (VTE) is a common cause of morbidity and mortality in hospitalized and surgical patients. To reduce risk, perioperative VTE prophylaxis is recommended for cancer patients undergoing surgical or interventional procedures. Magnetic resonance imaging (MRI) is increasingly used in interventional oncology when alternative imaging modalities do not adequately delineate malignancies. Extended periods of immobilization during MRI-guided interventions necessitate an MR compatible sequential compression device (SCD) for intra-procedural mechanical VTE prophylaxis. Such devices are not commercially available. Materials and methods: A standard SCD routinely used at our institution for VTE prophylaxis during interventional procedures was used. To satisfy MR safety requirements, the SCD controller was placed in the MR control room and connected to the compression sleeves in the magnet room through the wave guide using tubing extensions. The controller pressure sensor was used to monitor adequate pressure delivery and detect ineffective low or abnormal high pressure delivery. VTE prophylaxis was provided using the above mentioned device for 38 patients undergoing MR-guided ablations. Results: There was no evidence of device failure due to loss of pressure in the extension tubing assembly. No interference with the anesthesia or interventional procedures was documented. Conclusion: Although the controller of a standard SCD is labeled as “MR-unsafe”, the SCD can be used in interventional MR settings by placing the device outside the MR scanner room. Using serial tubing extensions did not cause device failure. The described method can be used to provide

  2. Hall effect in a strong magnetic field: Direct comparisons of compressible magnetohydrodynamics and the reduced Hall magnetohydrodynamic equations

    International Nuclear Information System (INIS)

    Martin, L. N.; Dmitruk, P.; Gomez, D. O.

    2010-01-01

    In this work we numerically test a model of Hall magnetohydrodynamics in the presence of a strong mean magnetic field: the reduced Hall magnetohydrodynamic model (RHMHD) derived by [Gomez et al., Phys. Plasmas 15, 102303 (2008)] with the addition of weak compressible effects. The main advantage of this model lies in the reduction of computational cost. Nevertheless, up until now the degree of agreement with the original Hall MHD system and the range of validity in a regime of turbulence were not established. In this work direct numerical simulations of three-dimensional Hall MHD turbulence in the presence of a strong mean magnetic field are compared with simulations of the weak compressible RHMHD model. The results show that the degree of agreement is very high (when the different assumptions of RHMHD, such as spectral anisotropy, are satisfied). Nevertheless, when the initial conditions are isotropic but the mean magnetic field is maintained strong, the results differ at the beginning but asymptotically reach a good agreement at relatively short times. We also found evidence that the compressibility still plays a role in the dynamics of these systems, and the weak compressible RHMHD model is able to capture these effects. In conclusion the weak compressible RHMHD model is a valid approximation of the Hall MHD turbulence in the relevant physical context.

  3. Direct current force sensing device based on compressive spring, permanent magnet, and coil-wound magnetostrictive/piezoelectric laminate.

    Science.gov (United States)

    Leung, Chung Ming; Or, Siu Wing; Ho, S L

    2013-12-01

    A force sensing device capable of sensing dc (or static) compressive forces is developed based on a NAS106N stainless steel compressive spring, a sintered NdFeB permanent magnet, and a coil-wound Tb(0.3)Dy(0.7)Fe(1.92)/Pb(Zr, Ti)O3 magnetostrictive∕piezoelectric laminate. The dc compressive force sensing in the device is evaluated theoretically and experimentally and is found to originate from a unique force-induced, position-dependent, current-driven dc magnetoelectric effect. The sensitivity of the device can be increased by increasing the spring constant of the compressive spring, the size of the permanent magnet, and/or the driving current for the coil-wound laminate. Devices of low-force (20 N) and high-force (200 N) types, showing high output voltages of 262 and 128 mV peak, respectively, are demonstrated at a low driving current of 100 mA peak by using different combinations of compressive spring and permanent magnet.

  4. Effects of JPEG data compression on magnetic resonance imaging evaluation of small vessels ischemic lesions of the brain

    International Nuclear Information System (INIS)

    Kuriki, Paulo Eduardo de Aguiar; Abdala, Nitamar; Nogueira, Roberto Gomes; Carrete Junior, Henrique; Szejnfeld, Jacob

    2006-01-01

    Objective: to establish the maximum achievable JPEG compression ratio without affecting quantitative and qualitative magnetic resonance imaging analysis of ischemic lesion in small vessels of the brain. Material and method: fifteen DICOM images were converted to JPEG with a compression ratio of 1:10 to 1:60 and were assessed together with the original images by three neuro radiologists. The number, morphology and signal intensity of the lesions were analyzed. Results: lesions were properly identified up to a 1:30 ratio. More lesions were identified with a 1:10 ratio then in the original images. Morphology and edges were properly evaluated up toa 1:40 ratio. Compression did not affect signal. Conclusion: small lesions were identified ( < 2 mm ) and in all compression ratios the JPEG algorithm generated image noise that misled observers to identify more lesions in JPEG images then in DICOM images, thus generating false-positive results.(author)

  5. The Grenoble station for producing strong transient magnetic fields higher than 100 teslas by an explosive driven flux compression

    International Nuclear Information System (INIS)

    Guillot, M.

    1976-01-01

    Reproducible transient magnetic fields up to 400 teslas (4 megaoersted) are achieved by a simple explosive driven flux compression. The results are described simply from the point of view of energy conversion. The problems of field measurements are studied: the precision is +-2% with a field cavity of 5 mm diameter [fr

  6. Electric-gun studies of conductors in high magnetic fields and experiments in dynamic flux compression

    International Nuclear Information System (INIS)

    Osher, J.E.; Chau, H.H.; Lee, R.S.; Tipton, R.E.; Weingart, R.C.

    1990-01-01

    Electric guns operate by discharging a fast capacitor bank through a thin, metallic bridge-foil load. The explosion of the foil and the accompanying magnetic forces acting on the bridge-foil plasma accelerate a thin flyer plate of dielectric material initially placed on top of the bridge foil. In hypervelocity impact studies with the linear electric gun, a thin, flat flyer is punched out of a cover sheet of dielectric (or dielectric/metallic composite) material by the explosion of the bridge foil and accelerated down a short barrel to impact on a target. In the coaxial gun, a cylindrical bridge foil is used to implode a cylindrical dielectric or dielectric/metallic composite (liner) flyer to produce a high peak compression through axial convergence. In this paper the authors discuss the range of currents, their rate of rise, and the magnetic fields attained by their fast capacitor banks, which supply power to the electric gun to explode the bridge foil. Also included is a study of the change of resistance of the bridge-foil element as a function of time for various flyer mass loadings for the linear geometry of the gun

  7. Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression

    International Nuclear Information System (INIS)

    Lasche, G.P.

    1988-01-01

    A method for recovering energy in an inertial confinement fusion reactor having a reactor chamber and a sphere forming means positioned above an opening in the reactor chamber is described, comprising: embedding a fusion target fuel capsule having a predetermined yield in the center of a hollow solid lithium tube and subsequently embedding the hollow solid lithium tube in a liquid lithium medium; using the sphere forming means for forming the liquid lithium into a spherical shaped liquid lithium mass having a diameter smaller than the length of the hollow solid lithium tube with the hollow solid lithium tube being positioned along a diameter of the spherical shaped mass, providing the spherical shaped liquid lithium mass with the fusion fuel target capsule and hollow solid lithium tube therein as a freestanding liquid lithium shaped spherical shaped mass without any external means for maintaining the spherical shape by dropping the liquid lithium spherical shaped mass from the sphere forming means into the reactor chamber; producing a magnetic field in the reactor chamber; imploding the target capsule in the reactor chamber to produce fusion energy; absorbing fusion energy in the liquid lithium spherical shaped mass to convert substantially all the fusion energy to shock induced kinetic energy of the liquid lithium spherical shaped mass which expands the liquid lithium spherical shaped mass; and compressing the magnetic field by expansion of the liquid lithium spherical shaped mass and recovering useful energy

  8. Compression Molding and Novel Sintering Treatments for Alnico Type-8 Permanent Magnets in Near-Final Shape with Preferred Orientation

    Science.gov (United States)

    Kassen, Aaron G.; White, Emma M. H.; Tang, Wei; Hu, Liangfa; Palasyuk, Andriy; Zhou, Lin; Anderson, Iver E.

    2017-09-01

    Economic uncertainty in the rare earth (RE) permanent magnet marketplace, as well as in an expanding electric drive vehicle market that favors permanent magnet alternating current synchronous drive motors, motivated renewed research in RE-free permanent magnets like "alnico," an Al-Ni-Co-Fe alloy. Thus, high-pressure, gas-atomized isotropic type-8H pre-alloyed alnico powder was compression molded with a clean burn- out binder to near-final shape and sintered to density >99% of cast alnico 8 (full density of 7.3 g/cm3). To produce aligned sintered alnico magnets for improved energy product and magnetic remanence, uniaxial stress was attempted to promote controlled grain growth, avoiding directional solidification that provides alignment in alnico 9. Successful development of solid-state powder processing may enable anisotropically aligned alnico magnets with enhanced energy density to be mass-produced.

  9. The way of prophylaxis of unfoundedness of pancreatojejunal anastomosis and hepaticojejunal anastomosis with pancreatoduodenal resection

    OpenAIRE

    Bakhtin, V.; Chikishev, S.

    2008-01-01

    The results of using of original method of transhepatic decompression drainage of pancreatojejunal anastomosis and hepaticojejunal anastomosis with pancreatoduodenal resection have been presented. The decreasing of postoperative complications' number and reduction of lethality while using the method have been discovered.

  10. Methodological aspects of magnetic resonance tomographic diagnostics of metastatic compressive fractures of the spine

    Directory of Open Access Journals (Sweden)

    Александр Павлович Мягков

    2015-06-01

    Full Text Available Aim of the study – to define an information value of the different pulse patterns for a qualitative estimation of MR-signals in the body of compressed vertebras.Methods: 50 patients with metastatic compressive fractures (MCF were examined using MRT. 30 (60% mans and 20 (40% woman, average age 60,8 +/- 12,5 years. Fractures in the different parts of spine were considered: cervical – 6 (12,0; thoracic – 25 (50,0 %; lumbar – 19 (38 %. Metastasis in the spine are more frequent at a cancer of mammary gland (20,0 %, kidneys (17,5 % and prostate gland (15,0 %, less frequent at a cancer of lungs, thyroid gland and sarcomas (7,5 %.MRT was done for all patients using apparatus with magnetic force 0,2, 1,5 and 0,36Т (AIRIS Mate, ECHELON of "HitachimedicalCorp.", Japan, “I-Open 0, 36” Chinein 3 projections receiving Т1-, Т2- weighted (Т1WI, Т2WI and diffusion-weighted images (DWIand also images with suppression of signals from an adipose tissue (STIR, Fat/sat.Results: the more obvious pulse patterns (PP at MCF of spine are – STIR (97,8 %, Т1WI и DWI (80 %. DWI can be used as a screening and addition for above-listed PP. The more objective criterion for a judgment about MCF is abnormal uptake of CM (60 % on diffuse type.Conclusions: for MRT visualization of MCF the most optimal are the next PP – STIR, Т1WI and DWI, with a sensitivity, respectively – 97,8 %, 80 %, and 80 %. DWI must supplement but not substitute all existing PP. On the post-contrast T1WI an objective criterion for MRT diagnostics of MCF is an abnormal uptake of CM on diffuse type. An alteration of signal characteristics in the body of compressed vertebras is an evidence of an alteration of structure, but for more precise definition of its character it is necessary to study its morphological alterations

  11. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    OpenAIRE

    Kensuke Tashiro, MD; Shuji Yamashita, MD; Mitsunaga Narushima, MD; Isao Koshima, MD; Shimpei Miyamoto, MD

    2017-01-01

    Background:. Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined...

  12. ECF2: A pulsed power generator based on magnetic flux compression for K-shell radiation production

    International Nuclear Information System (INIS)

    L'Eplattenier, P.; Lassalle, F.; Mangeant, C.; Hamann, F.; Bavay, M.; Bayol, F.; Huet, D.; Morell, A.; Monjaux, P.; Avrillaud, G.; Lalle, B.

    2002-01-01

    The 3 MJ energy stored ECF2 generator is developed at Centre d'Etudes de Gramat, France, for K-shell radiation production. This generator is based on microsecond LTD stages as primary generators, and on the magnetic flux compression scheme for power amplification from the microsecond to the 100ns regime. This paper presents a general overview of the ECF2 generator. The flux compression stage, a key component, will be studied in details. We will present its advantages and drawbacks. We will then present the first experimental and numerical results which show the improvements that have already been made on this scheme

  13. Magnetic Resonance Enhancement Patterns at the Different Ages of Symptomatic Osteoporotic Vertebral Compression Fractures

    Energy Technology Data Exchange (ETDEWEB)

    You, Ja Yeon; Lee, Joon Woo; Kim, Jung Eun; Kang, Heung Sik [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2013-06-15

    To investigate the magnetic resonance (MR) enhancement patterns of symptomatic osteoporotic vertebral compression fracture (VCF) according to the fracture age, based on the successful single-level percutaneous vertebroplasty (PVP) cases. The study included 135 patients who underwent contrast-enhanced MR imaging and successful PVP from 2005 to 2010 due to a single- level osteoporotic VCF. Two radiologists blinded to the fracture age evaluated the MR enhancement patterns in consensus. The MR enhancement patterns were classified according to the enhancing proportion to the vertebral height and the presence or extent of a non-enhancing cleft within the enhancing area on sagittal plane. The Fisher' exact test, Kruskal-Wallis test and Mann-Whitney U test were performed to assess the differences in the MR enhancement patterns according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. A diffuse enhancing area can be seen in not only the hyperacute and acute VCFs but also the chronic symptomatic VCFs. Symptomatic VCFs having a segmental enhancing area were all included in the hyperacute or acute stage. Most symptomatic osteoporotic VCFs had a non-enhancing cleft in the enhanced vertebral body (128/135, 94.8%). There was no statistical difference of the enhancement pattern according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. The most common pattern is a non-enhancing cleft within a diffuse enhanced vertebra.

  14. Magnetic Resonance Enhancement Patterns at the Different Ages of Symptomatic Osteoporotic Vertebral Compression Fractures

    International Nuclear Information System (INIS)

    You, Ja Yeon; Lee, Joon Woo; Kim, Jung Eun; Kang, Heung Sik

    2013-01-01

    To investigate the magnetic resonance (MR) enhancement patterns of symptomatic osteoporotic vertebral compression fracture (VCF) according to the fracture age, based on the successful single-level percutaneous vertebroplasty (PVP) cases. The study included 135 patients who underwent contrast-enhanced MR imaging and successful PVP from 2005 to 2010 due to a single- level osteoporotic VCF. Two radiologists blinded to the fracture age evaluated the MR enhancement patterns in consensus. The MR enhancement patterns were classified according to the enhancing proportion to the vertebral height and the presence or extent of a non-enhancing cleft within the enhancing area on sagittal plane. The Fisher' exact test, Kruskal-Wallis test and Mann-Whitney U test were performed to assess the differences in the MR enhancement patterns according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. A diffuse enhancing area can be seen in not only the hyperacute and acute VCFs but also the chronic symptomatic VCFs. Symptomatic VCFs having a segmental enhancing area were all included in the hyperacute or acute stage. Most symptomatic osteoporotic VCFs had a non-enhancing cleft in the enhanced vertebral body (128/135, 94.8%). There was no statistical difference of the enhancement pattern according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. The most common pattern is a non-enhancing cleft within a diffuse enhanced vertebra.

  15. Strong magnetization and Chern insulators in compressed graphene/CrI 3 van der Waals heterostructures

    Science.gov (United States)

    Zhang, Jiayong; Zhao, Bao; Zhou, Tong; Xue, Yang; Ma, Chunlan; Yang, Zhongqin

    2018-02-01

    Graphene-based heterostructures are a promising material system for designing the topologically nontrivial Chern insulating devices. Recently, a two-dimensional monolayer ferromagnetic insulator CrI3 was successfully synthesized in experiments [B. Huang et al., Nature (London) 546, 270 (2017), 10.1038/nature22391]. Here, these two interesting materials are proposed to build a heterostructure (Gr /CrI3). Our first-principles calculations show that the system forms a van der Waals (vdW) heterostructure, which is relatively facilely fabricated in experiments. A Chern insulating state is acquired in the Gr /CrI3 heterostructure if the vdW gap is compressed to a distance between about 3.3 and 2.4 Å, corresponding to a required external pressure between about 1.4 and 18.3 GPa. Amazingly, very strong magnetization (about 150 meV) is found in graphene, induced by the substrate CrI3, despite the vdW interactions between them. A low-energy effective model is employed to understand the mechanism. The work functions, contact types, and band alignments of the Gr /CrI3 heterostructure system are also studied. Our work demonstrates that the Gr /CrI3 heterostructure is a promising system to observe the quantum anomalous Hall effect at high temperatures (up to 45 K) in experiments.

  16. Relating speech production to tongue muscle compressions using tagged and high-resolution magnetic resonance imaging

    Science.gov (United States)

    Xing, Fangxu; Ye, Chuyang; Woo, Jonghye; Stone, Maureen; Prince, Jerry

    2015-03-01

    The human tongue is composed of multiple internal muscles that work collaboratively during the production of speech. Assessment of muscle mechanics can help understand the creation of tongue motion, interpret clinical observations, and predict surgical outcomes. Although various methods have been proposed for computing the tongue's motion, associating motion with muscle activity in an interdigitated fiber framework has not been studied. In this work, we aim to develop a method that reveals different tongue muscles' activities in different time phases during speech. We use fourdimensional tagged magnetic resonance (MR) images and static high-resolution MR images to obtain tongue motion and muscle anatomy, respectively. Then we compute strain tensors and local tissue compression along the muscle fiber directions in order to reveal their shortening pattern. This process relies on the support from multiple image analysis methods, including super-resolution volume reconstruction from MR image slices, segmentation of internal muscles, tracking the incompressible motion of tissue points using tagged images, propagation of muscle fiber directions over time, and calculation of strain in the line of action, etc. We evaluated the method on a control subject and two postglossectomy patients in a controlled speech task. The normal subject's tongue muscle activity shows high correspondence with the production of speech in different time instants, while both patients' muscle activities show different patterns from the control due to their resected tongues. This method shows potential for relating overall tongue motion to particular muscle activity, which may provide novel information for future clinical and scientific studies.

  17. Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields

    International Nuclear Information System (INIS)

    Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J.

    2013-01-01

    We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10 4 T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ∼50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities

  18. Contribution to the understanding of the high magnetic field compression produced by the implosion of a thin metal tube

    International Nuclear Information System (INIS)

    Besancon, Jacques

    1970-12-01

    In this report we present the essential phenomena which occur during the magnetic flux compression obtained by the explosive-driven implosion of a thin conducting liner: acceleration time, dynamic evolution, heating and instability behaviour of the liner; field diffusion through the conducting wall and resulting flux losses which condition the increasing field in the cavity. Various implosion models are proposed and the one most elaborated leads to a numerical computation of the flux compression. Repeated experiments have permitted us to define and improve the flux injection techniques, the optical and electrical diagnostics and, consequently, the final compressed field. We now know how to obtain and record reproducible fields of 12 MOe in 0.8 cm diameter cavities. The final phase or the liner 'turnaround' has been specially observed. All the implosion shots are compared to the theoretical expectation. It may be concluded that the liner electrical conductivity and its variation essentially determine the final flux value. (author) [fr

  19. Fingertip replantation without venous anastomosis.

    Science.gov (United States)

    Chen, Yi-Chieh; Chan, Fuan Chiang; Hsu, Chung-Chen; Lin, Yu-Te; Chen, Chien-Tzung; Lin, Chih-Hung

    2013-03-01

    Replantation of amputated fingertips is a technical challenge, as many salvage procedures fail because no suitable vein in the fingertip is available for anastomosis. In this study, we examined our experience in fingertip replantation in cases without venous anastomosis with our established fingertip replantation treatment protocol. Between August 2002 and August 2010, a retrospective study examined all patients who had undergone fingertip replantation at Chang-Gung Memorial Hospital. All the patients (n = 24) suffered from complete digital amputations at or distal to the interphalangeal joint of the thumb, or distal to distal interphalangeal joint of the fingers. A total of 30 fingertips that were salvaged by microsurgical anastomosis of the digital arteries but not of digital veins were included in this study. On satisfactory arterial anastomosis, a 2-mm incision was made over the fingertip with a number 11 Scalpel blade, and 0.1 to 0.2 mL heparin (5000 IU/mL) was injected subcutaneously around the incision immediately and once per day thereafter to ensure continuous blood drainage from the replanted fingertip. None of the replanted nail plate was removed, and no medical leeches were used. The perfusion of the replanted digits and patient's hemoglobin level were closely monitored. The wound bleeding was maintained until physiologic venous outflow was restored. Of 30 fingertips, 27 (90%) replanted fingertips survived. The average length needed for maintaining external bleeding by chemical leech was 6.8 days (range, 5-10 days). Twelve patients (including a 2-year-old child) received blood transfusions. The average amount of blood transfusion in the 23 adults was 4.0 units (range, 0-16 units) for each patient or 3.29 units (range, 0-14 units) for each digit. A 2-year-old child received 100 mL blood transfusion or 50 mL for each digit. This study showed that a protocol that promotes controlled bleeding from the fingertip is essential to achieve consistent high

  20. Experience with single-layer rectal anastomosis.

    OpenAIRE

    Khubchandani, M; Upson, J

    1981-01-01

    Anastomotic dehiscence following resection of the large intestine is a serious complication. Satisfactory results of single-layer anastomosis depend upon meticulous technique and a scrupulously clean colon. Out of 65 single-layer anastomoses involving the rectum, significant leakage occurred in 4 patients. The results are reported in order to draw attention to the safety and efficacy of one-layer anastomosis.

  1. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments

    Energy Technology Data Exchange (ETDEWEB)

    Waisman, E. M.; Reisman, D. B.; Stoltzfus, B. S.; Stygar, W. A.; Cuneo, M. E.; Haill, T. A.; Davis, J.-P.; Brown, J. L.; Seagle, C. T. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Spielman, R. B. [Idaho State University, Pocatello, Idaho 83201 (United States)

    2016-06-15

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called “bricks,” that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.–Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel “current-adder” architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L{sub 2} norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest.

  2. Local sparsity enhanced compressed sensing magnetic resonance imaging in uniform discrete curvelet domain

    International Nuclear Information System (INIS)

    Yang, Bingxin; Yuan, Min; Ma, Yide; Zhang, Jiuwen; Zhan, Kun

    2015-01-01

    Compressed sensing(CS) has been well applied to speed up imaging by exploring image sparsity over predefined basis functions or learnt dictionary. Firstly, the sparse representation is generally obtained in a single transform domain by using wavelet-like methods, which cannot produce optimal sparsity considering sparsity, data adaptivity and computational complexity. Secondly, most state-of-the-art reconstruction models seldom consider composite regularization upon the various structural features of images and transform coefficients sub-bands. Therefore, these two points lead to high sampling rates for reconstructing high-quality images. In this paper, an efficient composite sparsity structure is proposed. It learns adaptive dictionary from lowpass uniform discrete curvelet transform sub-band coefficients patches. Consistent with the sparsity structure, a novel composite regularization reconstruction model is developed to improve reconstruction results from highly undersampled k-space data. It is established via minimizing spatial image and lowpass sub-band coefficients total variation regularization, transform sub-bands coefficients l 1 sparse regularization and constraining k-space measurements fidelity. A new augmented Lagrangian method is then introduced to optimize the reconstruction model. It updates representation coefficients of lowpass sub-band coefficients over dictionary, transform sub-bands coefficients and k-space measurements upon the ideas of constrained split augmented Lagrangian shrinkage algorithm. Experimental results on in vivo data show that the proposed method obtains high-quality reconstructed images. The reconstructed images exhibit the least aliasing artifacts and reconstruction error among current CS MRI methods. The proposed sparsity structure can fit and provide hierarchical sparsity for magnetic resonance images simultaneously, bridging the gap between predefined sparse representation methods and explicit dictionary. The new augmented

  3. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Science.gov (United States)

    Yamashita, Shuji; Narushima, Mitsunaga; Koshima, Isao; Miyamoto, Shimpei

    2017-01-01

    Background: Although supermicrosurgical anastomosis is a widely known reconstructive microsurgical technique, it is difficult to perform. To expand the clinical use of supermicrosurgery, we used hemi-intravascular stenting (hemi-IVaS), which is performed by inserting an intravascular stent into one side of the vessel. We conducted lymphaticovenular anastomosis, free perforator flap transfer, and fingertip replantation with supermicrosurgical anastomosis using hemi-IVaS technique and examined its usefulness. Methods: Between January 2013 and February 2015, 11 anastomoses in 11 cases of lymphaticovenular anastomosis for lymphedema patients, 14 anastomoses in 7 cases of free perforator flap transfer with supermicrosurgical perforator-to-perforator anastomosis, and 9 anastomoses in 5 cases of fingertip replantation were performed using hemi-IVaS. Time required for anastomosis and complications were examined. Flap survival rate was also examined in free perforator flap transfer cases and fingertip replantation cases. Results: In all cases, anastomoses were performed without complications such as inadvertent catching of the back wall of the vessel during the procedure or the need for reanastomoses. The average time required to complete the anastomosis was 16.4 ± 3.20 minutes using the hemi IVaS technique. All flaps survived in the supermicrosurgical perforator-to-perforator anastomosis as well as fingertip replantation cases. Conclusions: Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery. PMID:29263952

  4. Laser-assisted vascular anastomosis

    Science.gov (United States)

    Kao, Race L.; Tsao-Wu, George; Magovern, George J.

    1990-06-01

    The milliwatt CO2 laser and a thermal activated binding compound (20% serum albumin) were used for microvascular anastomoses. Under general anesthesia, the femoral arteries (0.7 to 1.0 mm diameter) of 6 rats were isolated. After the left femoral artery in each rat was clamped and transected, the vessel was held together with 3 equidistant 10-0 Xomed sutures. The cut edges were coated 3 to 4 times with the albumin solution and sealed with the CO2 laser (power density = 120 W/cm2). The binding compound solidified to a translucent tensile substance which supported the anastomosis until self healing and repair were achieved. The right femoral artery was used as sham operated control. Complete hemostasis and patency were observed in every case immediately and at 1, 3, and 6 months following surgery. The binding compound absorbed most of the laser energy thus minimizing thermal injury to the underlying tissue. Mongrel dogs weighing 28 to 33 kg were anesthetized and prepared for sterile surgical procedures. In 5 dogs, the femoral and jugular veins were exposed, transected, and anastomosed using a CO2 laser (Sharplan 1040) with the binding compound. In another 12 dogs, cephalic veins were isolated and used for aortocoronary artery bypass procedures. The Sharplan 1040 CO2 laser and 20% albumin solution were utilized to complete the coronary anastomoses in 6 dogs, and 6 dogs were used as controls by suturing the vessels. Again, hemostasis, patency, and minimal tissue damage were observed immediately and 6 weeks after the procedures. Improved surgical results, reduced operating time, minimized tissue damage, and enhanced anastomotic integrity are the advantages of laser assisted vascular anastomosis with a thermal activated binding compound.

  5. Steady fall of isothermal, resistive-viscous, compressible fluid across magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Low, B. C., E-mail: low@ucar.edu [High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colorado 80301 (United States); Egan, A. K., E-mail: andrea.egan@colorado.edu [Barnard College, New York, New York 10027, USA and Department of Physics, Colorado University, Boulder, Colorado 80309 (United States)

    2014-06-15

    This is a basic MHD study of the steady fall of an infinite, vertical slab of isothermal, resistive-viscous, compressible fluid across a dipped magnetic field in uniform gravity. This double-diffusion steady flow in unbounded space poses a nonlinear but numerically tractable, one-dimensional (1D) free-boundary problem, assuming constant coefficients of resistivity and viscosity. The steady flow is determined by a dimensionless number μ{sub 1} proportional to the triple product of the two diffusion coefficients and the square of the linear total mass. For a sufficiently large μ{sub 1}, the Lorentz, viscous, fluid-pressure, and gravitational forces pack and collimate the fluid into a steady flow of a finite width defined by the two zero-pressure free-boundaries of the slab with vacuum. The viscous force is essential in this collimation effect. The study conjectures that in the regime μ{sub 1}→0, the 1D steady state exists only for μ{sub 1}∈Ω, a spectrum of an infinite number of discrete values, including μ{sub 1} = 0 that corresponds to two steady states, the classical zero-resistivity static slab of Kippenhahn and Schlüter [R. Kippenhahn and A. Schlüter, Z. Astrophys. 43, 36 (1957)] and its recent generalization [B. C. Low et al., Astrophys. J. 755, 34 (2012)] to admit an inviscid resistive flow. The pair of zero-pressure boundaries of each of the μ{sub 1}→0 steady-state slabs are located at infinity. Computational evidence suggests that the Ω steady-states are densely distributed around μ{sub 1} = 0, as an accumulation point, but are sparsely separated by open intervals of μ{sub 1}-values for which the slab must be either time-dependent or spatially multi-dimensional. The widths of these intervals are vanishingly small as μ{sub 1}→0. This topological structure of physical states is similar to that described by Landau and Liftshitz [L. D. Landau and E. M. Lifshitz, Fluid Mechanics (Addison-Wesley, Reading, MA, 1959)] to explain the onset

  6. Primary small bowel anastomosis in generalised peritonitis

    NARCIS (Netherlands)

    deGraaf, JS; van Goor, Harry; Bleichrodt, RP

    Objective: To find out if primary small bowel anastomosis of the bowel is safe in patients with generalised peritonitis who are treated by planned relaparotomies. Design: Retrospective study. Setting: University hospital, The Netherlands. Subjects. 10 Patients with generalised purulent peritonitis

  7. Multispectral tissue characterization for intestinal anastomosis optimization

    Science.gov (United States)

    Cha, Jaepyeong; Shademan, Azad; Le, Hanh N. D.; Decker, Ryan; Kim, Peter C. W.; Kang, Jin U.; Krieger, Axel

    2015-10-01

    Intestinal anastomosis is a surgical procedure that restores bowel continuity after surgical resection to treat intestinal malignancy, inflammation, or obstruction. Despite the routine nature of intestinal anastomosis procedures, the rate of complications is high. Standard visual inspection cannot distinguish the tissue subsurface and small changes in spectral characteristics of the tissue, so existing tissue anastomosis techniques that rely on human vision to guide suturing could lead to problems such as bleeding and leakage from suturing sites. We present a proof-of-concept study using a portable multispectral imaging (MSI) platform for tissue characterization and preoperative surgical planning in intestinal anastomosis. The platform is composed of a fiber ring light-guided MSI system coupled with polarizers and image analysis software. The system is tested on ex vivo porcine intestine tissue, and we demonstrate the feasibility of identifying optimal regions for suture placement.

  8. The study of vascular dynamics for the effect of a compress pack on pain relief using magnetic resonance angiography

    International Nuclear Information System (INIS)

    Baek, Ji Won; Lim, Young Khi

    2015-01-01

    This study was to investigate the effects of the hot compress pack on alleviating local muscular discomfort, stiffness in limbs as well as the chronic pains such as migraine in terms of hemodynamics. In this study, the hot compress band was put on the neck and the local physiological change on the stimulation site and the cranial blood circulation change were examined. We recruited healthy volunteers (n=8, mean age: 32.13 (4.61)), who participated in the magnetic resonance imaging (MRI) study. Local skin color and temperature were measured for the local effect of the hot compress band and the changes of intra-cranial and extra-cranial blood vessels were examined with MR angiography (MRA) images. The skin temperature increased from 36.4 degrees Celsius at the rest condition to 36.7 degrees Celsius and 37.1 degrees Celsius after 15 min and 30 min stimulation, respectively. The change of the extra-cranial blood vessels between pre-stimulation and post-stimulation of 30 min was significantly increased (+38.8%), while the change of the intra-cranial blood vessels was negligible. In this study, we demonstrated that the hot compress band on the neck yielded the increase of local skin temperature on the stimulation site and it made an effect on the extracranial circulation. In conclusion, the stimulation with a hot compress could facilitate the blood circulation, causing to relieve the muscular discomfort, stiffness in limbs as well as the chronic pains such as migraine

  9. The study of vascular dynamics for the effect of a compress pack on pain relief using magnetic resonance angiography

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Ji Won; Lim, Young Khi [Gachon University, Sungnam (Korea, Republic of)

    2015-12-15

    This study was to investigate the effects of the hot compress pack on alleviating local muscular discomfort, stiffness in limbs as well as the chronic pains such as migraine in terms of hemodynamics. In this study, the hot compress band was put on the neck and the local physiological change on the stimulation site and the cranial blood circulation change were examined. We recruited healthy volunteers (n=8, mean age: 32.13 (4.61)), who participated in the magnetic resonance imaging (MRI) study. Local skin color and temperature were measured for the local effect of the hot compress band and the changes of intra-cranial and extra-cranial blood vessels were examined with MR angiography (MRA) images. The skin temperature increased from 36.4 degrees Celsius at the rest condition to 36.7 degrees Celsius and 37.1 degrees Celsius after 15 min and 30 min stimulation, respectively. The change of the extra-cranial blood vessels between pre-stimulation and post-stimulation of 30 min was significantly increased (+38.8%), while the change of the intra-cranial blood vessels was negligible. In this study, we demonstrated that the hot compress band on the neck yielded the increase of local skin temperature on the stimulation site and it made an effect on the extracranial circulation. In conclusion, the stimulation with a hot compress could facilitate the blood circulation, causing to relieve the muscular discomfort, stiffness in limbs as well as the chronic pains such as migraine.

  10. Influence of applied compressive stress on the hysteresis curves and magnetic domain structure of grain-oriented transverse Fe–3%Si steel

    Czech Academy of Sciences Publication Activity Database

    Perevertov, Oleksiy; Schäfer, R.

    2012-01-01

    Roč. 45, č. 13 (2012), "135001-1"-"135001-11" ISSN 0022-3727 Grant - others:GA AV ČR(CZ) M100100906 Institutional research plan: CEZ:AV0Z10100520 Keywords : hysteresis curve * magnetic domains * compressive stress * goss steel * effective field Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.528, year: 2012

  11. Compression-induced deep tissue injury examined with magnetic resonance imaging and histology

    NARCIS (Netherlands)

    Stekelenburg, A.; Oomens, C. W. J.; Strijkers, G. J.; Nicolay, K.; Bader, D. L.

    2006-01-01

    The underlying mechanisms leading to deep tissue injury after sustained compressive loading are not well understood. It is hypothesized that initial damage to muscle fibers is induced mechanically by local excessive deformation. Therefore, in this study, an animal model was used to study early

  12. Magnetic force micropiston: An integrated force/microfluidic device for the application of compressive forces in a confined environment

    Science.gov (United States)

    Fisher, J. K.; Kleckner, N.

    2014-02-01

    Cellular biology takes place inside confining spaces. For example, bacteria grow in crevices, red blood cells squeeze through capillaries, and chromosomes replicate inside the nucleus. Frequently, the extent of this confinement varies. Bacteria grow longer and divide, red blood cells move through smaller and smaller passages as they travel to capillary beds, and replication doubles the amount of DNA inside the nucleus. This increase in confinement, either due to a decrease in the available space or an increase in the amount of material contained in a constant volume, has the potential to squeeze and stress objects in ways that may lead to changes in morphology, dynamics, and ultimately biological function. Here, we describe a device developed to probe the interplay between confinement and the mechanical properties of cells and cellular structures, and forces that arise due to changes in a structure's state. In this system, the manipulation of a magnetic bead exerts a compressive force upon a target contained in the confining space of a microfluidic channel. This magnetic force microfluidic piston is constructed in such a way that we can measure (a) target compliance and changes in compliance as induced by changes in buffer, extract, or biochemical composition, (b) target expansion force generated by changes in the same parameters, and (c) the effects of compression stress on a target's structure and function. Beyond these issues, our system has general applicability to a variety of questions requiring the combination of mechanical forces, confinement, and optical imaging.

  13. Carotid-anterior cerebral artery anastomosis on MR angiography: a university hospital-based study

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Akira; Saito, Naoko; Okada, Yoshitaka; Inoue, Kaiji [Saitama Medical University International Medical Center, Department of Diagnostic Radiology, Hidaka, Saitama (Japan)

    2012-01-15

    Rarely in the anterior circulation, an anastomosis of the carotid and anterior cerebral arteries occurs when an anomalous branch arises from the ophthalmic segment of the internal carotid artery and anastomoses with the A1-A2 junction of the anterior communicating artery. Right-side predominance is known. To our knowledge, the incidence of carotid-anterior cerebral artery anastomosis has not been reported, so we researched cases in our institution records to determine incidence and investigated characteristic features of the condition on magnetic resonance (MR) angiography. To isolate such cases, we retrospectively reviewed cranial MR angiographic images of 3,491 consecutive patients in our institution. We found three cases with carotid-anterior cerebral artery anastomosis (two men, one woman), representing an incidence of 0.086%. The anastomosis was on the right in all three cases. A normal A1 segment of the anterior cerebral artery (ACA) was present in two cases but could not be identified in the remaining case on MR angiographic images that included source images. Two of the three patients demonstrated associated arterial variations in their carotid systems. On MR angiography, we observed a 0.086% incidence of carotid-anterior cerebral artery anastomosis in our institution and reaffirmed the right-side predominance of this anomaly. We found a high frequency of other associated arterial variations in the carotid system. (orig.)

  14. 3-D branching of magnetic domains on compressed si-fe steel with goss texture

    Czech Academy of Sciences Publication Activity Database

    Perevertov, Oleksiy; Schaefer, R.; Stupakov, Oleksandr

    2014-01-01

    Roč. 50, č. 11 (2014), s. 2007804 ISSN 0018-9464 R&D Projects: GA ČR GB14-36566G; GA ČR GA13-18993S Institutional support: RVO:68378271 Keywords : grain-oriented silicon steel * Kerr microscopy * magnetic domains * stress Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.386, year: 2014

  15. Microvascular Anastomosis: Proposition of a Learning Curve.

    Science.gov (United States)

    Mokhtari, Pooneh; Tayebi Meybodi, Ali; Benet, Arnau; Lawton, Michael T

    2018-04-14

    Learning to perform a microvascular anastomosis is one of the most difficult tasks in cerebrovascular surgery. Previous studies offer little regarding the optimal protocols to maximize learning efficiency. This failure stems mainly from lack of knowledge about the learning curve of this task. To delineate this learning curve and provide information about its various features including acquisition, improvement, consistency, stability, and recall. Five neurosurgeons with an average surgical experience history of 5 yr and without any experience in bypass surgery performed microscopic anastomosis on progressively smaller-caliber silastic tubes (Biomet, Palm Beach Gardens, Florida) during 24 consecutive sessions. After a 1-, 2-, and 8-wk retention interval, they performed recall test on 0.7-mm silastic tubes. The anastomoses were rated based on anastomosis patency and presence of any leaks. Improvement rate was faster during initial sessions compared to the final practice sessions. Performance decline was observed in the first session of working on a smaller-caliber tube. However, this rapidly improved during the following sessions of practice. Temporary plateaus were seen in certain segments of the curve. The retention interval between the acquisition and recall phase did not cause a regression to the prepractice performance level. Learning the fine motor task of microvascular anastomosis adapts to the basic rules of learning such as the "power law of practice." Our results also support the improvement of performance during consecutive sessions of practice. The objective evidence provided may help in developing optimized learning protocols for microvascular anastomosis.

  16. Rayleigh Taylor instability of two superposed compressible fluids in un-magnetized plasma

    International Nuclear Information System (INIS)

    Sharma, P K; Tiwari, A; Argal, S; Chhajlani, R K

    2014-01-01

    The linear Rayleigh Taylor instability of two superposed compressible Newtonian fluids is discussed with the effect of surface tension which can play important roles in space plasma. As in both the superposed Newtonian fluids, the system is stable for potentially stable case and unstable for potentially unstable case in the present problem also. The equations of the problem are solved by normal mode method and a dispersion relation is obtained for such a system. The behaviour of growth rate is examined in the presence of surface tension and it is found that the surface tension has stabilizing influence on the Rayleigh Taylor instability of two superposed compressible fluids. Numerical analysis is performed to show the effect of sound velocity and surface tension on the growth rate of Rayleigh Taylor instability. It is found that both parameters have stabilizing influence on the growth rate of Rayleigh Taylor instability.

  17. Condensed argon isentropic compression with ultrahigh magnetic field pressure: Experimental design. Post-shot report

    Energy Technology Data Exchange (ETDEWEB)

    Bykov, A.I.; Boriskov, G.V.; Dolotenko, M.I. [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation)] [and others

    1996-12-31

    This report continues the series of work devoted to experimental study of a high-dense condensed argon state. Remember that according to work of Kwon et. al., hexagonal close-packed structure is profitable in terms of energy rather than face-centered argon structure (stable with zero pressure). What is most interesting and intriguing here is the issue of possible argon metallization, when it is compressed up to the densities more than 9.17 g/cm{sup 3}. In the experiment of 1995 (the arrangement and data are described in a cited reference) the authors recorded appearance of conductivity in argon, which is non-conductive in the initial state, when it is compressed more than a factor of four. The peak value of argon specific conductivity recorded in this experiment did not exceed 10 (Ohm x cm){sup {minus}1}. This value of conductivity is characteristic of semiconductors, but not metals, which have 10{sup 4} (Ohm x cm){sup {minus}1}. At this stage of the work the main attention is paid to recording of argon conductive state and studying the possibilities of multiframed radiography of the sample in the compressed state.

  18. Safe Resection and Primary Anastomosis of Gangrenous Sigmoid ...

    African Journals Online (AJOL)

    %) of the sigmoid volvulus was gangrenous and 85.2% of all the sigmoid volvulus was managed by resection and primary anastomosis. Complications seen after resection and primary anastomosis were anastomotic leak at 4.5%, resection.

  19. Technical Nuances of Exposing Rat Common Carotid Arteries for Practicing Microsurgical Anastomosis.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Aklinski, Joseph; Gandhi, Sirin; Lawton, Michael T; Preul, Mark C

    2018-04-17

    Animal models are commonly used in training protocols for microsurgical vascular anastomosis. Rat common carotid arteries (CCAs) are frequently used for this purpose. Much attention has been paid to the technical details of various anastomosis configurations using these arteries. However, technical nuances of exposing rat CCAs have been understudied. The purpose of this study is to describe nuances of technique for safely and efficiently exposing rat CCAs in preparation for a vascular anastomosis. Bilateral CCAs were exposed and prepared for anastomosis in 10 anesthetized Sprague-Dawley rats through a midline cervical incision. The exposed length of the CCA was measured. Additionally, technical nuances of exposure and surgically relevant anatomic details were recorded. The CCAs were exposed from the sternoclavicular joint to their bifurcation (average length, 19.1 ± 2.8 mm). Tenets important for a safe and efficient exposure of the CCAs included 1) generous subcutaneous dissection to expose the external jugular veins (EJVs), 2) avoiding injury to or compression of the EJVs, 3) superior mobilization of the salivary glands, 4) division of internal jugular veins, 5) opening the carotid sheath at its midlevel and from medial to lateral, and 6) avoiding injury to the vagus nerve or sympathetic trunk. Using the principles introduced in this study, trainees may safely and efficiently expose rat CCAs in preparation for a bypass. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Significance of venous anastomosis in fingertip replantation.

    Science.gov (United States)

    Hattori, Yasunori; Doi, Kazuteru; Ikeda, Keisuke; Abe, Yukio; Dhawan, Vikas

    2003-03-01

    Adequate venous outflow is the most important factor for successful fingertip replantation. The authors have attempted venous anastomosis in all cases of fingertip replantation to overcome postoperative congestion. In this article, the significance of venous repair for fingertip replantation is described from the authors' results of 64 complete fingertip amputations in 55 consecutive patients, which were replanted from January of 1996 to June of 2001. The overall survival rate was 86 percent. Of the 44 replantations in zone I, 37 survived, and the success rate was 84 percent. Of the 20 replantations in zone II, 18 survived, and the success rate was 90 percent. Venous anastomosis was attempted in all cases, but it was possible in 39 zone I and in all zone II replantations. For arterial repair, vein grafts were necessary in 17 of the 44 zone I and in one of the 20 zone II replantations; for venous repair, they were necessary in six zone I replantations and one zone II replantation. Postoperative vascular complications occurred in 15 replantations. There were five cases of arterial thrombosis and 10 cases of venous congestion. Venous congestion occurred in nine zone I and one zone II replantations. In five of these 10 replantations, venous anastomosis was not possible. In another five replantations, venous outflow was established at the time of surgery, but occlusion occurred subsequently. Except for the five failures resulting from arterial thrombosis, successful venous repair was possible in 49 of 59 replantations (83 percent). Despite the demand for skillful microsurgical technique and longer operation time, the authors' results using venous anastomosis in successful fingertip replantations are encouraging. By performing venous anastomosis, external bleeding can be avoided and a higher survival rate can be achieved. Venous anastomosis for fingertip replantation is a reliable and worthwhile procedure.

  1. Morbidity Following Coloanal Anastomosis: A Comparison of Colonic J-Pouch vs Straight Anastomosis.

    Science.gov (United States)

    Brown, Shaun; Margolin, David A; Altom, Laura K; Green, Heather; Beck, David E; Kann, Brian R; Whitlow, Charles B; Vargas, Herschel David

    2018-02-01

    Low rectal tumors are often treated with sphincter-preserving resection followed by coloanal anastomosis. The purpose of this study was to compare the short-term complications following straight coloanal anastomosis vs colonic J-pouch anal anastomosis. Patients were identified who underwent proctectomy for rectal neoplasia followed by coloanal anastomosis in the 2008 to 2013 American College of Surgeons National Surgical Quality Improvement Program database. Demographic characteristics and 30-day postoperative complications were compared between groups. A national sample was extracted from the American College of Surgeons National Surgical Quality Improvement Project database. Inpatients following proctectomy and coloanal anastomosis for rectal cancer were selected. Demographic characteristics and 30-day postoperative complications were compared between the 2 groups. One thousand three hundred seventy patients were included, 624 in the straight anastomosis group and 746 in the colonic J-pouch group. Preoperative characteristics were similar between groups, with the exception of preoperative radiation therapy (straight anastomosis 35% vs colonic J-pouch 48%, p = 0.0004). Univariate analysis demonstrated that deep surgical site infection (3.7% vs 1.4%, p = 0.01), septic shock (2.25% vs 0.8%, p = 0.04), and return to the operating room (8.8% vs 5.0%, p = 0.0006) were more frequent in the straight anastomosis group vs the colonic J-pouch group. Major complications were also higher (23% vs 14%, p = 0.0001) and length of stay was longer in the straight anastomosis group vs the colonic J-pouch group (8.9 days vs 8.1 days, p = 0.02). After adjusting for covariates, major complications were less following colonic J-pouch vs straight anastomosis (OR, 0.57; CI, 0.38-0.84; p = 0.005). Subgroup analysis of patients who received preoperative radiation therapy demonstrated no difference in major complications between groups. This study had those limitations inherent to a

  2. [Comparative study of intestinal anastomosis with manual suture and biofragmentable ring in dogs under corticosteroid administration].

    Science.gov (United States)

    Fernandes, L C; Matos, D; Novelli, M D; Kim, S B

    2000-01-01

    This study analyzed intestinal anastomoses by manual suture and by compression with biofragmentable ring under delay of cicatrization administering parenteral corticoids. Twenty dogs were divided into two groups: control and test, the latter submitted to intramuscular administration of hydrocortisone hemisuccinate, 25 to 33 mg/kg/day, on the 30th preoperative and 7th postoperative days. During surgery, each animal underwent two colon sections with anastomosis by manual suture in a single extramucous plane and compression with biofragmentable ring. The animals were sacrificed 7 days after the procedure to evaluate the anastomoses. In the postoperative period, one death occurred in the test group and two in the control group, caused by nonblocked fistula in the anastomoses by ring compression. Statistically, there was a similar incidence of adherences, fistulas, afferent dilatation and obstruction using comparison methods. On microscopy, deficiency in mucous regeneration of the anastomoses by compression was observed. Computerized histological analysis evidenced in the anastomoses by compression, a greater inflammatory reaction, greater edema of the submucous membrane and enlarged scars. It was concluded that, with the biofragmentable ring, in colonic anastomosis under delay of cicatrization induced by corticoids, similar results to manual suture regarding to postoperative complications incidence were obtained; ring, however, determined worse mucous regeneration and greater cicatricial inflammatory reaction.

  3. Compression of a spherically symmetric deuterium-tritium plasma liner onto a magnetized deuterium-tritium target

    International Nuclear Information System (INIS)

    Santarius, J. F.

    2012-01-01

    Converging plasma jets may be able to reach the regime of high energy density plasmas (HEDP). The successful application of plasma jets to magneto-inertial fusion (MIF) would heat the plasma by fusion products and should increase the plasma energy density. This paper reports the results of using the University of Wisconsin’s 1-D Lagrangian, radiation-hydrodynamics, fusion code BUCKY to investigate two MIF converging plasma jet test cases originally analyzed by Samulyak et al.[Physics of Plasmas 17, 092702 (2010)]. In these cases, 15 cm or 5 cm radially thick deuterium-tritium (DT) plasma jets merge at 60 cm from the origin and converge radially onto a DT target magnetized to 2 T and of radius 5 cm. The BUCKY calculations reported here model these cases, starting from the time of initial contact of the jets and target. Compared to the one-temperature Samulyak et al. calculations, the one-temperature BUCKY results show similar behavior, except that the plasma radius remains about twice as long near maximum compression. One-temperature and two-temperature BUCKY results differ, reflecting the sensitivity of the calculations to timing and plasma parameter details, with the two-temperature case giving a more sustained compression.

  4. A Novel Compressed Sensing Method for Magnetic Resonance Imaging: Exponential Wavelet Iterative Shrinkage-Thresholding Algorithm with Random Shift

    Directory of Open Access Journals (Sweden)

    Yudong Zhang

    2016-01-01

    Full Text Available Aim. It can help improve the hospital throughput to accelerate magnetic resonance imaging (MRI scanning. Patients will benefit from less waiting time. Task. In the last decade, various rapid MRI techniques on the basis of compressed sensing (CS were proposed. However, both computation time and reconstruction quality of traditional CS-MRI did not meet the requirement of clinical use. Method. In this study, a novel method was proposed with the name of exponential wavelet iterative shrinkage-thresholding algorithm with random shift (abbreviated as EWISTARS. It is composed of three successful components: (i exponential wavelet transform, (ii iterative shrinkage-thresholding algorithm, and (iii random shift. Results. Experimental results validated that, compared to state-of-the-art approaches, EWISTARS obtained the least mean absolute error, the least mean-squared error, and the highest peak signal-to-noise ratio. Conclusion. EWISTARS is superior to state-of-the-art approaches.

  5. A Novel Compressed Sensing Method for Magnetic Resonance Imaging: Exponential Wavelet Iterative Shrinkage-Thresholding Algorithm with Random Shift

    Science.gov (United States)

    Zhang, Yudong; Yang, Jiquan; Yang, Jianfei; Liu, Aijun; Sun, Ping

    2016-01-01

    Aim. It can help improve the hospital throughput to accelerate magnetic resonance imaging (MRI) scanning. Patients will benefit from less waiting time. Task. In the last decade, various rapid MRI techniques on the basis of compressed sensing (CS) were proposed. However, both computation time and reconstruction quality of traditional CS-MRI did not meet the requirement of clinical use. Method. In this study, a novel method was proposed with the name of exponential wavelet iterative shrinkage-thresholding algorithm with random shift (abbreviated as EWISTARS). It is composed of three successful components: (i) exponential wavelet transform, (ii) iterative shrinkage-thresholding algorithm, and (iii) random shift. Results. Experimental results validated that, compared to state-of-the-art approaches, EWISTARS obtained the least mean absolute error, the least mean-squared error, and the highest peak signal-to-noise ratio. Conclusion. EWISTARS is superior to state-of-the-art approaches. PMID:27066068

  6. Fast modeling of flux trapping cascaded explosively driven magnetic flux compression generators.

    Science.gov (United States)

    Wang, Yuwei; Zhang, Jiande; Chen, Dongqun; Cao, Shengguang; Li, Da; Liu, Chebo

    2013-01-01

    To predict the performance of flux trapping cascaded flux compression generators, a calculation model based on an equivalent circuit is investigated. The system circuit is analyzed according to its operation characteristics in different steps. Flux conservation coefficients are added to the driving terms of circuit differential equations to account for intrinsic flux losses. To calculate the currents in the circuit by solving the circuit equations, a simple zero-dimensional model is used to calculate the time-varying inductance and dc resistance of the generator. Then a fast computer code is programmed based on this calculation model. As an example, a two-staged flux trapping generator is simulated by using this computer code. Good agreements are achieved by comparing the simulation results with the measurements. Furthermore, it is obvious that this fast calculation model can be easily applied to predict performances of other flux trapping cascaded flux compression generators with complex structures such as conical stator or conical armature sections and so on for design purpose.

  7. Anisotropy of linear thermal expansion and compressibility of Y.sub.2./sub.Fe.sub.17./sub. under pressure and its correlation to magnetic structure

    Czech Academy of Sciences Publication Activity Database

    Arnold, Zdeněk; Kamarád, Jiří; Prokhnenko, Olexandr; Ritter, C.; Eto, T.; Honda, F.; Oomi, G.; Garcia-Landa, B.

    2002-01-01

    Roč. 22, - (2002), s. 175-179 ISSN 0895-7959 R&D Projects: GA ČR GA106/02/0943; GA AV ČR IAA1010018; GA MŠk ME 165 Institutional research plan: CEZ:AV0Z1010914 Keywords : intermetallic compounds * pressure effect * compressibility * thermal expansion * magnetic structure Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.414, year: 2002

  8. Hemi-Intravascular Stenting for Supermicrosurgical Anastomosis

    Directory of Open Access Journals (Sweden)

    Kensuke Tashiro, MD

    2017-11-01

    Conclusions:. Hemi-IVaS could be a useful alternative to conventional intravascular stenting techniques and is also effective for supermicrosurgical perforator-to-perforator anastomosis. Further studies are needed to improve the success rate and to explore its other possible utilizations in supermicrosurgery.

  9. Epidural block and neostigmine cause anastomosis leak

    Directory of Open Access Journals (Sweden)

    Ataro G

    2016-05-01

    Full Text Available Getu Ataro Department of Anesthesia, Jimma University, Jimma, EthiopiaI read the article by Phillips entitled, “Reducing gastrointestinal anastomotic leak rates: review of challenges and solutions”, published in the journal of Open Access Surgery with enthusiasm and found it crucial for perioperative management of patients with gastrointestinal (GI surgery, particularly anastomosis. I appreciate the author’s exhaustive search of literature and discussion with some limitation on review basics like methodology, which may affect the reliability of the review findings. The effects of risk factors for anastomosis leak, such as malnutrition, smoking, steroid use, bowel preparation, chemotherapy, duration of surgery, use of pressors, intravenous fluid administration, blood transfusion, and surgical anastomotic technique, were well discussed.1 However, from anesthesia perspective, there are some other well-studied risk factors that can affect healing of anastomosis wound and cause anastomosis leak. Among others, the effect of neostigmine and epidural block has been reported in many studies since half a century ago. View the original paper by Phillips

  10. Radial magnetic compression in the expelled jet of a plasma deflagration accelerator

    International Nuclear Information System (INIS)

    Loebner, Keith T. K.; Underwood, Thomas C.; Mouratidis, Theodore; Cappelli, Mark A.

    2016-01-01

    A spectroscopic study of a pulsed plasma deflagration accelerator is carried out that confirms the existence of a strong compression in the emerging jet at the exit plane of the device. An imaging spectrometer is used to collect broadened Hα emission from a transaxial slice of the emerging jet at high spatial resolution, and the radial plasma density profile is computed from Voigt fits of the Abel inverted emissivity profiles. The plasma temperature, determined via Doppler broadening of impurity line emission, is compared against the temperature predictions of a radial magnetohydrodynamic equilibrium model applied to the measured density profiles. Empirical scaling laws developed for the plasma density, combined with the measured and predicted temperatures, indicate that a radially equilibrated Z-pinch is formed within the expelled plasma jet at the exit plane during the deflagration process.

  11. Microbunching and RF Compression

    International Nuclear Information System (INIS)

    Venturini, M.; Migliorati, M.; Ronsivalle, C.; Ferrario, M.; Vaccarezza, C.

    2010-01-01

    Velocity bunching (or RF compression) represents a promising technique complementary to magnetic compression to achieve the high peak current required in the linac drivers for FELs. Here we report on recent progress aimed at characterizing the RF compression from the point of view of the microbunching instability. We emphasize the development of a linear theory for the gain function of the instability and its validation against macroparticle simulations that represents a useful tool in the evaluation of the compression schemes for FEL sources.

  12. Laparoscopic right colon resection with intracorporeal anastomosis.

    Science.gov (United States)

    Chang, Karen; Fakhoury, Mathew; Barnajian, Moshe; Tarta, Cristi; Bergamaschi, Roberto

    2013-05-01

    This study was performed to evaluate short-term clinical outcomes of laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon. This was a retrospective study of selected patients who underwent laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon for tumors or Crohn's disease by a single surgeon from July 2002 through June 2012. Data were retrieved from an Institutional Review Board-approved database. Study end point was postoperative adverse events, including mortality, complications, reoperations, and readmissions at 30 days. Antiperistaltic side-to-side anastomoses were fashioned laparoscopically with a 60-mm-long stapler cartridge and enterocolotomy was hand-sewn intracorporeally in two layers. Values were expressed as medians (ranges) for continuous variables. There were 243 patients (143 females) aged 61 (range = 19-96) years, with body mass index of 29 (18-43) kg/m(2) and ASA 1:2:3:4 of 52:110:77:4; 30 % had previous abdominal surgery and 38 % had a preexisting comorbidity. There were 84 ileocolic resections with ileo ascending anastomosis and 159 right colectomies with ileotransverse anastomosis. Operating time was 135 (60-220) min. Estimated blood loss was 50 (10-600) ml. Specimen extraction site incision length was 4.1 (3-4.4) cm. Conversion rate was 3 % and there was no mortality at 30 days, 15 complications (6.2 %), and 8 reoperations (3.3 %). Readmission rate was 8.7 %. Length of stay was 4 (2-32) days. Pathology confirmed Crohn's disease in 84 patients, adenocarcinoma in 152, and other tumors in 7 patients. Laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon resulted in a favorable outcome in selected patients with Crohn's disease or tumors of the right colon.

  13. Shock-front compression of the magnetic field in the Canis Majoris R1 star-formation region

    International Nuclear Information System (INIS)

    Vrba, F.J.; Baierlein, R.; Herbst, W.; Wesleyan Univ., Middletown, CT; Van Vleck Observatory, Middletown, CT)

    1987-01-01

    Results are presented from a linear polarization survey at optical wavelengths of over 140 stars in the direction of the CMa R1 star-formation region; 26 of these are clearly associated with nebulosity within the area. The observations were obtained in order to test the argument of Herbst et al. (1978) that star formation in CMa R1 is driven by a shock wave from a nearby supernova (Herbs and Assousa, 1977 and 1978). The polarizations are found to be consistent with a simple model of the compression by a supernova-induced spherical shock front of an initially uniform interstellar magnetic field. The polarization vectors are inconsistent with a scenario of quiescent cloud collapse along magnetic-field lines. Multicolor polarimetry of the nebular stars provides evidence of grain growth toward increasing cloud optical depth, characterized by a ratio of total-to-selective extinction of R = 3.0 at E(B-V) = 0.23, increasing to R = 4.2 at E(B-V) = 0.7. 15 references

  14. Left mainstem bronchial narrowing: a vascular compression syndrome? Evaluation by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Hungate, R.G.; Newman, B.; Meza, M.P.

    1998-01-01

    Background and objective. Vascular compression of the left mainstem bronchus (LMSB) between the descending aorta (DA) and pulmonary artery (PA) has been suggested as a cause for LMSB narrowing in children. These anatomic relationships have not been compared with those in children with a normal LMSB. Materials and methods. We undertook a retrospective review of the medical and radiologic records of 10 symptomatic young children (1-19 months, 5 boys, 5 girls) with MR demonstration of LMSB narrowing and compared them to 40 young children without great vessel or bronchial abnormality on MR (1 week-19 months, 28 boys, 12 girls). Chest MR evaluation included assessment of airway and great vessel anatomy with specific attention to the course of the LMSB and its relationship to the adjacent DA and PA. The position of the DA in relation to the spine was carefully evaluated. Results. Five children had focal and five had diffuse LMSB narrowing. DA position at the level of the crossing LMSB: in 40 % of symptomatic children the DA was located in front of the adjacent vertebral body; in 40 %, 1 / 2 - 3 / 4 and in 20 % 1 / 4 - 1 / 2 of the circumference of the DA was located anterior to the spine. In the control group, the DA was prespinal in 10 %, with a trend toward a more paraspinal location of the DA. The trend toward a difference in position of the DA between symptomatic and control patients was statistically significant (P < 0.05). DA position was not related to age (up to 19 months). At the level where the LMSB crossed the DA, a segment of the PA was located anterior to the LMSB, more often the right PA (RPA) or pulmonary bifurcation in symptomatic children and the left PA (LPA) in controls. No correlation was apparent between length of LMSB narrowing and DA or PA position. Chest radiographic abnormalities, when present, were subtle. Excellent MR/bronchoscopic correlation of LMSB narrowing was found in nine of the ten symptomatic children. One child underwent posterior

  15. Applications of the computer codes FLUX2D and PHI3D for the electromagnetic analysis of compressed magnetic field generators and power flow channels

    International Nuclear Information System (INIS)

    Hodgdon, M.L.; Oona, H.; Martinez, A.R.; Salon, S.; Wendling, P.; Krahenbuhl, L.; Nicolas, A.; Nicolas, L.

    1990-01-01

    The authors present the results of three electromagnetic field problems for compressed magnetic field generators and their associated power flow channels. The first problem is the computation of the transient magnetic field in a two-dimensional model of a helical generator during loading. The second problem is the three-dimensional eddy current patterns in a section of an armature beneath a bifurcation point of a helical winding. The authors' third problem is the calculation of the three-dimensional electrostatic fields in a region known as the post-hole convolute in which a rod connects the inner and outer walls of a system of three concentric cylinders through a hole in the middle cylinder. While analytic solutions exist for many electromagnetic filed problems in cases of special and ideal geometries, the solution of these and similar problems for the proper analysis and design of compressed magnetic field generators and their related hardware require computer simulations

  16. Polarisation and compression of 3He for Magnetic Resonance Imaging purposes

    International Nuclear Information System (INIS)

    Geurts, D. G.; Brand, J. F. J. van den; Bulten, H. J.; Poolman, H. R.; Ferro-Luzzi, M.; Nicolay, K.

    1998-01-01

    Magnetic Resonance Imaging is often used in medical science as a diagnostic tool for the human body. Conventional MRI uses the NMR signal from the protons of water molecules in tissue to image the interior of the patient's body. However, for certain areas such as the lungs and airways, the usage of a highly polarised gas yields better results. We are currently constructing an apparatus that uses polarised 3 He gas to produce detailed images of those signal-deficient moyeties. We also plan to study possible uptake of polarised 3 He gas by the circulatory system to image other organs

  17. Electron gun for a multiple beam klystron with magnetic compression of the electron beams

    Science.gov (United States)

    Ives, R. Lawrence; Tran, Hien T; Bui, Thuc; Attarian, Adam; Tallis, William; David, John; Forstall, Virginia; Andujar, Cynthia; Blach, Noah T; Brown, David B; Gadson, Sean E; Kiley, Erin M; Read, Michael

    2013-10-01

    A multi-beam electron gun provides a plurality N of cathode assemblies comprising a cathode, anode, and focus electrode, each cathode assembly having a local cathode axis and also a central cathode point defined by the intersection of the local cathode axis with the emitting surface of the cathode. Each cathode is arranged with its central point positioned in a plane orthogonal to a device central axis, with each cathode central point an equal distance from the device axis and with an included angle of 360/N between each cathode central point. The local axis of each cathode has a cathode divergence angle with respect to the central axis which is set such that the diverging magnetic field from a solenoidal coil is less than 5 degrees with respect to the projection of the local cathode axis onto a cathode reference plane formed by the device axis and the central cathode point, and the local axis of each cathode is also set such that the angle formed between the cathode reference plane and the local cathode axis results in minimum spiraling in the path of the electron beams in a homogenous magnetic field region of the solenoidal field generator.

  18. Current singularities at finitely compressible three-dimensional magnetic null points

    International Nuclear Information System (INIS)

    Pontin, D.I.; Craig, I.J.D.

    2005-01-01

    The formation of current singularities at line-tied two- and three-dimensional (2D and 3D, respectively) magnetic null points in a nonresistive magnetohydrodynamic environment is explored. It is shown that, despite the different separatrix structures of 2D and 3D null points, current singularities may be initiated in a formally equivalent manner. This is true no matter whether the collapse is triggered by flux imbalance within closed, line-tied null points or driven by externally imposed velocity fields in open, incompressible geometries. A Lagrangian numerical code is used to investigate the finite amplitude perturbations that lead to singular current sheets in collapsing 2D and 3D null points. The form of the singular current distribution is analyzed as a function of the spatial anisotropy of the null point, and the effects of finite gas pressure are quantified. It is pointed out that the pressure force, while never stopping the formation of the singularity, significantly alters the morphology of the current distribution as well as dramatically weakening its strength. The impact of these findings on 2D and 3D magnetic reconnection models is discussed

  19. Evaluation of heterogeneous metabolic profile in an orthotopic human glioblastoma xenograft model using compressed sensing hyperpolarized 3D 13C magnetic resonance spectroscopic imaging.

    Science.gov (United States)

    Park, Ilwoo; Hu, Simon; Bok, Robert; Ozawa, Tomoko; Ito, Motokazu; Mukherjee, Joydeep; Phillips, Joanna J; James, C David; Pieper, Russell O; Ronen, Sabrina M; Vigneron, Daniel B; Nelson, Sarah J

    2013-07-01

    High resolution compressed sensing hyperpolarized (13)C magnetic resonance spectroscopic imaging was applied in orthotopic human glioblastoma xenografts for quantitative assessment of spatial variations in (13)C metabolic profiles and comparison with histopathology. A new compressed sensing sampling design with a factor of 3.72 acceleration was implemented to enable a factor of 4 increase in spatial resolution. Compressed sensing 3D (13)C magnetic resonance spectroscopic imaging data were acquired from a phantom and 10 tumor-bearing rats following injection of hyperpolarized [1-(13)C]-pyruvate using a 3T scanner. The (13)C metabolic profiles were compared with hematoxylin and eosin staining and carbonic anhydrase 9 staining. The high-resolution compressed sensing (13)C magnetic resonance spectroscopic imaging data enabled the differentiation of distinct (13)C metabolite patterns within abnormal tissues with high specificity in similar scan times compared to the fully sampled method. The results from pathology confirmed the different characteristics of (13)C metabolic profiles between viable, non-necrotic, nonhypoxic tumor, and necrotic, hypoxic tissue. Copyright © 2012 Wiley Periodicals, Inc.

  20. Clinical repercussions of Martin-Gruber anastomosis: anatomical study

    Directory of Open Access Journals (Sweden)

    Cristina Schmitt Cavalheiro

    2016-04-01

    Full Text Available OBJECTIVE: The main objective of this study was to describe Martin-Gruber anastomosis anatomically and to recognize its clinical repercussions. METHOD: 100 forearms of 50 adult cadavers were dissected in an anatomy laboratory. The dissection was performed by means of a midline incision along the entire forearm and the lower third of the upper arm. Two flaps including skin and subcutaneous tissue were folded back on the radial and ulnar sides, respectively. RESULTS: Nerve communication between the median and ulnar nerves in the forearm (Martin-Gruber anastomosis was found in 27 forearms. The anastomosis was classified into six types: type I: anastomosis between the anterior interosseous nerve and the ulnar nerve (n = 9; type II: anastomosis between the anterior interosseous nerve and the ulnar nerve at two points (double anastomosis (n = 2; type III: anastomosis between the median nerve and the ulnar nerve (n = 4; type IV: anastomosis between branches of the median nerve and ulnar nerve heading toward the flexor digitorum profundus muscle of the fingers; these fascicles form a loop with distal convexity (n = 5; type V: intramuscular anastomosis (n = 5; and type VI: anastomosis between a branch of the median nerve to the flexor digitorum superficialis muscle and the ulnar nerve (n = 2. CONCLUSION: Knowledge of the anatomical variations relating to the innervation of the hand has great importance, especially with regard to physical examination, diagnosis, prognosis and surgical treatment. If these variations are not given due regard, errors and other consequences will be inevitable.

  1. Significance of coupling device for vessel anastomosis in esophageal reconstruction.

    Science.gov (United States)

    Watanabe, Y; Horiuchi, A; Yamamoto, Y; Kikkawa, H; Kusunose, H; Sugishita, H; Sato, K; Yoshida, M; Yukumi, S; Kawachi, K

    2005-01-01

    To prevent an anastomotic failure due to impaired blood supply, several trials have been performed such as preoperative ischemic conditioning by transarterial embolization of the left gastric, right gastric and splenic arteries or microvascular anastomosis. We assess the significance of an automatic anastomotic coupling device for vessel anastomosis, which we have continuously utilized, to simplify the task and shorten the anastomotic time since March 1999. 8 patients who underwent venous anastomosis by an automatic anastomotic coupling device were evaluated for the time of anastomosis, total ischemic time and outcomes. Venous anastomosis was completed within 5 minutes on average. Microscopic arterial anastomosis by hand took 35 minutes on average. For gastric tube reconstruction, venous anastomosis by an automatic coupling device took only 5 minutes. The top of the gastric tube showed congestion before venous anastomosis, but rapidly recovered from it after anastomosis. Postoperative endoscopic observation of the mucosal color of the replaced intestine or gastric tube was started 3 days after surgery and revealed no ischemia or congestion. The postoperative course was uneventful except one case suffering from pneumonia but leakage was not observed in any case. An automatic anastomotic coupling device can perform an easy and reliable vascular anastomosis for patients who undergo esophageal reconstruction. The device may shorten the operating time and consequently the ischemic time of the gastric tube or jejunal or colonic graft, which in turn may lead to a decrease of complications.

  2. Genetic control of anastomosis in Podospora anserina.

    Science.gov (United States)

    Tong, Laetitia Chan Ho; Silar, Philippe; Lalucque, Hervé

    2014-09-01

    We developed a new microscopy procedure to study anastomoses in the model ascomycete Podospora anserina and compared it with the previous method involving the formation of balanced heterokaryons. Both methods showed a good correlation. Heterokaryon formation was less quantifiable, but enabled to observe very rare events. Microscopic analysis evidenced that anastomoses were greatly influence by growth conditions and were severely impaired in the IDC mutants of the PaMpk1, PaMpk2, IDC1 and PaNox1 pathways. Yet some mutants readily formed heterokaryons, albeit with a delay when compared to the wild type. We also identified IDC(821), a new mutant presenting a phenotype similar to the other IDC mutants, including lack of anastomosis. Complete genome sequencing revealed that IDC(821) was affected in the orthologue of the Neurospora crassa So gene known to control anastomosis in several other ascomycetes. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Randomized trial on the application of biofragmentable anastomosis ring in intestinal anastomosis.

    Science.gov (United States)

    Chen, Shuang; Yang, Bin; He, Jia-hui; Zhang, Yu-chao; Lai, Dong-ming

    2009-08-05

    The biofragmentable anastomosis ring (BAR) is a simple alternative device to create intestinal anastomosis. Our study was designed to evaluate the clinical value of BAR in intestinal anastomosis. A total of 167 patients performed intestinal anastomosis from January 2002 to February 2006 were randomized to BAR group (n = 82) and manual suture group (n = 85) as control. They were equally allocated to the two groups regarding sex, age, site of anastomosis, emergent or elective surgery and contaminant diseases. The results of postoperative complications and recovery were recorded in each group. Eighty-seven intraperitoneal BAR anastomoses were completed in 82 patients. Two and one postoperative deaths were recorded in BAR and suture group, respectively, no deaths were directly related to anastomotic technique. In suture group, anastomotic leakage and early bleeding both occurred in two patients respectively, no anastomotic bleeding occurred in BAR group, one patient in BAR group developed enterocutaneous fistulae. Perioperative bleeding, operation time and length of hospitalization were similar in two groups (P > 0.05). Time for return of bowel function was significantly shortened in BAR group than that in suture group (P emergent intraperitoneal intestinal anastomotic surgery.

  4. Accelerated two-dimensional cine DENSE cardiovascular magnetic resonance using compressed sensing and parallel imaging.

    Science.gov (United States)

    Chen, Xiao; Yang, Yang; Cai, Xiaoying; Auger, Daniel A; Meyer, Craig H; Salerno, Michael; Epstein, Frederick H

    2016-06-14

    Cine Displacement Encoding with Stimulated Echoes (DENSE) provides accurate quantitative imaging of cardiac mechanics with rapid displacement and strain analysis; however, image acquisition times are relatively long. Compressed sensing (CS) with parallel imaging (PI) can generally provide high-quality images recovered from data sampled below the Nyquist rate. The purposes of the present study were to develop CS-PI-accelerated acquisition and reconstruction methods for cine DENSE, to assess their accuracy for cardiac imaging using retrospective undersampling, and to demonstrate their feasibility for prospectively-accelerated 2D cine DENSE imaging in a single breathhold. An accelerated cine DENSE sequence with variable-density spiral k-space sampling and golden angle rotations through time was implemented. A CS method, Block LOw-rank Sparsity with Motion-guidance (BLOSM), was combined with sensitivity encoding (SENSE) for the reconstruction of under-sampled multi-coil spiral data. Seven healthy volunteers and 7 patients underwent 2D cine DENSE imaging with fully-sampled acquisitions (14-26 heartbeats in duration) and with prospectively rate-2 and rate-4 accelerated acquisitions (14 and 8 heartbeats in duration). Retrospectively- and prospectively-accelerated data were reconstructed using BLOSM-SENSE and SENSE. Image quality of retrospectively-undersampled data was quantified using the relative root mean square error (rRMSE). Myocardial displacement and circumferential strain were computed for functional assessment, and linear correlation and Bland-Altman analyses were used to compare accelerated acquisitions to fully-sampled reference datasets. For retrospectively-undersampled data, BLOSM-SENSE provided similar or lower rRMSE at rate-2 and lower rRMSE at rate-4 acceleration compared to SENSE (p cine DENSE provided good image quality and expected values of displacement and strain. BLOSM-SENSE-accelerated spiral cine DENSE imaging with 2D displacement encoding can be

  5. Magnetic field effects on ultrafast lattice compression dynamics of Si(111) crystal when excited by linearly-polarized femtosecond laser pulses

    Science.gov (United States)

    Hatanaka, Koji; Odaka, Hideho; Ono, Kimitoshi; Fukumura, Hiroshi

    2007-03-01

    Time-resolved X-ray diffraction measurements of Si (111) single crystal are performed when excited by linearly-polarized femtosecond laser pulses (780 nm, 260 fs, negatively-chirped, 1 kHz) under a magnetic field (0.47 T). Laser fluence on the sample surface is 40 mJ/cm^2, which is enough lower than the ablation threshold at 200 mJ/cm^2. Probing X-ray pulses of iron characteristic X-ray lines at 0.193604 and 0.193998 nm are generated by focusing femtosecond laser pulses onto audio-cassette tapes in air. Linearly-polarized femtosecond laser pulse irradiation onto Si(111) crystal surface induces transient lattice compression in the picosecond time range, which is confirmed by transient angle shift of X-ray diffraction to higher angles. Little difference of compression dynamics is observed when the laser polarization is changed from p to s-pol. without a magnetic field. On the other hand, under a magnetic field, the lattice compression dynamics changes when the laser is p-polarized which is vertical to the magnetic field vector. These results may be assigned to photo-carrier formation and energy-band distortion.

  6. Primary anastomosis or ostomy in necrotizing enterocolitis?

    Science.gov (United States)

    Haricharan, Ramanathapura N; Gallimore, Jade Palazzola; Nasr, Ahmed

    2017-11-01

    In neonates requiring operation for necrotizing enterocolitis (NEC), the complications due to enterostomy (ES) and the need for another operation to restore continuity have prompted several surgeons to employ primary anastomosis (PA) after resection as the operative strategy of choice. Our objective was to compare primary anastomosis to stoma formation in this population using systematic review and meta-analysis. Publications describing both interventions were identified by searching multiple databases. Appropriate studies that reported outcomes after PA and ES for NEC were included for analysis that was performed using the MedCalc3000 software. Results are reported as odds ratios (OR, 95% CI). No randomized trials were identified. Twelve studies were included for the final analysis. Neonates who underwent PA were associated with significantly less risk of mortality when compared to those who underwent ES (OR 0.34, 95% CI 0.17-0.68, p 0.002), possibly due to differences in severity of NEC. Although the types of complications in these groups were different, there was no significant difference in risk of complication (OR 0.86, 0.55-1.33, p 0.50). In neonates undergoing an operation for severe NEC, there is no significant difference in the risk of complications between primary anastomosis and enterostomy. A definitive suggestion cannot be made regarding the choice of one operative strategy over another.

  7. Adiabatic Quasi-Spherical Compressions Driven by Magnetic Pressure for Inertial Confinement Fusion

    International Nuclear Information System (INIS)

    Nash, Thomas J.

    2000-01-01

    The magnetic implosion of a high-Z quasi-spherical shell filled with DT fuel by the 20-MA Z accelerator can heat the fuel to near-ignition temperature. The attainable implosion velocity on Z, 13-cm/micros, is fast enough that thermal losses from the fuel to the shell are small. The high-Z shell traps radiation losses from the fuel, and the fuel reaches a high enough density to reabsorb the trapped radiation. The implosion is then nearly adiabatic. In this case the temperature of the fuel increases as the square of the convergence. The initial temperature of the fuel is set by the heating of an ion acoustic wave to be about 200-eV after a convergence of 4. To reach the ignition temperature of 5-keV an additional convergence of 5 is required. The implosion dynamics of the quasi-spherical implosion is modeled with the 2-D radiation hydrodynamic code LASNEX. LASNEX shows an 8-mm diameter quasi-spherical tungsten shell on Z driving 6-atmospheres of DT fuel nearly to ignition at 3.5-keV with a convergence of 20. The convergence is limited by mass flow along the surface of the quasi-spherical shell. With a convergence of 20 the final spot size is 400-microm in diameter

  8. [Billroth I anastomosis with biodegradable anastomosis ring in the animal model].

    Science.gov (United States)

    Dietz, U A; Debus, E S; Hirt, A L; Czeczko, N G; Nassif, P A; Repka, J C; Malafaia, S; Geiger, D; Thiede, A

    1999-01-01

    In the present study, the Billroth-I anastomosis with the biofragmentable anastomosis ring was examined in dogs. 24 dogs were randomized into a group of manual suturing (n = 12) and a BAR-group (n = 12). In the group of manual suturing, a distal gastric resection and gastroduodenostomy with sero-submucous suture was performed. In the BAR-group, the distal gastric resection was done with the linear stapler PLC-75, whereby the BAR gastroduodenostomy crossed the stapling line. The dogs were evaluated on p.o. days 4, 14, and 30 and tested for bursting strength and bursting location, appearance of mucosa, hydroxyprolin concentration, and histologic features. There was no functional disorder in the gastrointestinal transit in any animal; in summary with regard to the various parameters, the crossing of BAR and stapling line does not represent any additional risk factor in the Billroth-I anastomosis in dogs.

  9. A magnetic particle time-of-flight (MagPTOF) diagnostic for measurements of shock- and compression-bang time at the NIF (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Rinderknecht, H. G., E-mail: hgr@mit.edu; Sio, H.; Frenje, J. A.; Gatu Johnson, M.; Zylstra, A. B.; Sinenian, N.; Rosenberg, M. J.; Li, C. K.; Sèguin, F. H.; Petrasso, R. D. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Magoon, J.; Agliata, A.; Shoup, M.; Glebov, V. U.; Hohenberger, M.; Stoeckl, C.; Sangster, T. C. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States); Ayers, S.; Bailey, C. G.; Rygg, J. R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

    2014-11-15

    A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D{sup 3}He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D{sup 3}He-proton signal-to-background by a factor of 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D{sup 3}He-filled surrogate implosions at the NIF.

  10. A magnetic particle time-of-flight (MagPTOF) diagnostic for measurements of shock- and compression-bang time at the NIF (invited).

    Science.gov (United States)

    Rinderknecht, H G; Sio, H; Frenje, J A; Magoon, J; Agliata, A; Shoup, M; Ayers, S; Bailey, C G; Gatu Johnson, M; Zylstra, A B; Sinenian, N; Rosenberg, M J; Li, C K; Sèguin, F H; Petrasso, R D; Rygg, J R; Kimbrough, J R; Mackinnon, A; Bell, P; Bionta, R; Clancy, T; Zacharias, R; House, A; Döppner, T; Park, H S; LePape, S; Landen, O; Meezan, N; Robey, H; Glebov, V U; Hohenberger, M; Stoeckl, C; Sangster, T C; Li, C; Parat, J; Olson, R; Kline, J; Kilkenny, J

    2014-11-01

    A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D(3)He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D(3)He-proton signal-to-background by a factor of 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D(3)He-filled surrogate implosions at the NIF.

  11. Development of the apparatus for measuring magnetic properties of electrical steel sheets in arbitrary directions under compressive stress normal to their surface

    Directory of Open Access Journals (Sweden)

    Yoshitaka Maeda

    2017-05-01

    Full Text Available In designing motors, one must grasp the magnetic properties of electrical steel sheets considering actual conditions in motors. Especially important is grasping the stress dependence of magnetic power loss. This paper describes a newly developed apparatus to measure two-dimensional (2-D magnetic properties (properties under the arbitrary alternating and the rotating flux conditions of electrical steel sheets under compressive stress normal to the sheet surface. The apparatus has a 2-D magnetic excitation circuit to generate magnetic fields in arbitrary directions in the evaluation area. It also has a pressing unit to apply compressive stress normal to the sheet surface. During measurement, it is important to apply uniform stress throughout the evaluation area. Therefore, we have developed a new flux density sensor using needle probe method. It is composed of thin copper foils sputtered on electrical steel sheets. By using this sensor, the stress can be applied to the surface of the specimen without influence of this sensor. This paper described the details of newly developed apparatus with this sensor, and measurement results of iron loss by using are shown.

  12. Development of the apparatus for measuring magnetic properties of electrical steel sheets in arbitrary directions under compressive stress normal to their surface

    Science.gov (United States)

    Maeda, Yoshitaka; Urata, Shinya; Nakai, Hideo; Takeuchi, Yuuya; Yun, Kyyoul; Yanase, Shunji; Okazaki, Yasuo

    2017-05-01

    In designing motors, one must grasp the magnetic properties of electrical steel sheets considering actual conditions in motors. Especially important is grasping the stress dependence of magnetic power loss. This paper describes a newly developed apparatus to measure two-dimensional (2-D) magnetic properties (properties under the arbitrary alternating and the rotating flux conditions) of electrical steel sheets under compressive stress normal to the sheet surface. The apparatus has a 2-D magnetic excitation circuit to generate magnetic fields in arbitrary directions in the evaluation area. It also has a pressing unit to apply compressive stress normal to the sheet surface. During measurement, it is important to apply uniform stress throughout the evaluation area. Therefore, we have developed a new flux density sensor using needle probe method. It is composed of thin copper foils sputtered on electrical steel sheets. By using this sensor, the stress can be applied to the surface of the specimen without influence of this sensor. This paper described the details of newly developed apparatus with this sensor, and measurement results of iron loss by using are shown.

  13. Clampless anastomosis with an intraluminal thermosensitive gel: first application in reconstructive microsurgery and literature review.

    Science.gov (United States)

    Giessler, G A; Fischborn, G T; Schmidt, A B

    2012-01-01

    Microvascular clamps of various designs provide a bloodless field for a safe anastomosis but can cause intimal lesions, occupy space in confined sites and have a risk of backwalling due to vessel flattening. They are often insufficient in their haemostatic effect in plaque-filled atherosclerotic vessels. A new, CE-certified thermosensitive gel (LeGoo™) clinically proven in cardiovascular surgery allows a clampless microanastomosis technique. We operated on a series of five consecutive patients aged 24-71 years with six flaps for lower-extremity reconstruction using a clampless anastomosis technique with LeGoo™. We transplanted one fabricated chimaeric fibula plus gracilis, three gracilis muscle and one anterolateral thigh (ALT) flap. Pre- and postoperative protocols were similar to a 'standard' procedure with micro-clamps. All flaps survived completely except for a small area on fibula skin island, which was unrelated to gel use. The gel-assisted technique has a quick learning curve, according to this case series. The veins should be sutured first to prevent stasis in the flap. The gel provides circular stenting and gentle distension of the vessels for a safe and blood-free anastomotic site. It is completely dissolved after completion of the anastomosis with cold saline irrigation. Repolymerisation in the periphery will not occur, making it safe for microvascular flap surgery. From the experiences from this series and other specialities, the use of the thermosensitive gel LeGoo™ permits a safe clampless microanastomosis technique minimising mechanical vessel manipulation and compression. This makes it an attractive alternative to micro-clamps, especially for atherosclerotic arteries and confined anastomosis sites. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. Pancreatic anastomosis leakage management following pancreaticoduodenectomy how could be manage the anastomosis leakage after pancreaticoduodenectomy?

    Directory of Open Access Journals (Sweden)

    Seyed Abbas Tabatabei

    2015-01-01

    Full Text Available Background: Pancreatic anastomosis leakage and fistula formation following pancreaticoduodenectomy (Whipple′s procedure is a common complication. Delay in timely diagnosis and proper management is associated with high morbidity and mortality. To report our experience with management of pancreatic fistula following Whipple′s procedure. Materials and Methods: In this retrospective study, medical records of 90 patients who underwent Whipple′s procedure from 2009 to 2013 at our medical center were reviewed for documents about pancreatic anastomosis leakage and fistula formation. Results: There were 15 patients who developed pancreatico-jejunal anastomosis leakage. In 6 patients (3 males and 3 females the leakage was mild (conservative therapy was administered, but in 9 patients (6 males and 3 females, there was severe leakage. For the latter group, surgical intervention was done (2 cases underwent re-anastomosis and for 7 cases pancreatico-jejunal stump ligation was done along with drainage of the location. Conclusion: In severe pancreatic anastomotic leakage, it is better to intervene surgically as soon as possible by debridement of the distal part of the pancreas and ligation of the stump with nonabsorbable suture. Furthermore, debridement of the jejunum should be done, and the stump should be ligated thoroughly along with drainage.

  15. Tracheal resection and anastomosis in dogs.

    Science.gov (United States)

    Lau, R E; Schwartz, A; Buergelt, C D

    1980-01-15

    Resection and end-to-end anastomosis of the trachea is a practical procedure for the correction of various forms of tracheal stenosis. Preplacing retention sutures facilitates manipulation of the trachea and rapid apposition of the tracheal ends. These same sutures then relieve tension on the primary suture line, assuring early epithelialization. Two dogs with tracheal stenosis were treated by use of this technique. Slight narrowing of the trachea was evident postoperatively in both dogs, but neither dyspnea nor coughing occurred during the follow-up period.

  16. The use of cyanoacrylate in surgical anastomosis: An alternative to ...

    African Journals Online (AJOL)

    To present anastomosis with cyanoacrylate as a cheap, simple, fast, and available technique for anastomosis in urological, vascular, gynecological, and general surgical procedures. This method may in the future be a good alternative to microsurgery, particularly in centers where facilities are unavailable and the financial ...

  17. Hypoplasia of the internal carotid artery with intercavernous anastomosis

    International Nuclear Information System (INIS)

    Chen, C.J.; Wang, L.J.; Wong, Y.C.; Chen, S.T.; Hsieh, F.Y.

    1998-01-01

    We report a symptomatic case of unilateral hypoplasia of the internal carotid artery with an intercavernous anastomosis, a very rare developmental anomaly. The symptoms were caused by occlusion of the proximal middle cerebral artery which possibly related to the haemodynamic stress caused by the anomalous intercavernous anastomosis. (orig.)

  18. Predicting burst pressure of radiofrequency-induced colorectal anastomosis by bio-impedance measurement.

    Science.gov (United States)

    Zhao, Lingxi; Zhou, Yu; Song, Chengli; Wang, Zhigang; Cuschieri, Alfred

    2017-03-01

    The present study investigates the relationship between bio-impedance and burst pressure of colorectal anastomosis created by radiofrequency (RF)-induced tissue fusion. Colorectal anastomosis were created with ex vivo porcine colorectal segments, during which 5 levels of compression pressure were applied by a custom-made bipolar prototype, with 5 replicate experiments at each compression pressure. Instant anastomotic tensile strength was assessed by burst pressure. Bio-impedance of fused tissue was measured by Impedance Analyzer across frequency that 100 Hz to 3 MHz. Statistical analysis shows only a weak correlation between bio-impedance modulus and burst pressures at frequency of 445 kHz ([Formula: see text]  =  -0.426, P  =  0.099  >  0.05). In contrast, results demonstrated a highly significant negative correlation between reactance modulus and burst pressures ([Formula: see text]  =  -0.812, P  =  0.000  <  0.05). The decrease in mean reactance modulus with increasing burst pressures was highly significant (P  =  0.019  <  0.05). The observed strong negative correlation between reactance modulus and burst pressures at frequency of 445 kHz indicates that reactance is likely to be a good index for tensile strength of RF-induced colorectal anastomosis, and should be considered for inclusion in a feedback loops in devices design.

  19. Evaluation of a novel thermosensitive heparin-poloxamer hydrogel for improving vascular anastomosis quality and safety in a rabbit model.

    Directory of Open Access Journals (Sweden)

    Ying-Zheng Zhao

    Full Text Available Despite progress in the design of advanced surgical techniques, stenosis recurs in a large percentage of vascular anastomosis. In this study, a novel heparin-poloxamer (HP hydrogel was designed and its effects for improving the quality and safety of vascular anastomosis were studied. HP copolymer was synthesized and its structure was confirmed by Fourier transform infrared spectroscopy (FTIR and nuclear magnetic resonance spectroscopy ((1H-NMR. Hydrogels containing HP were prepared and their important characteristics related to the application in vascular anastomosis including gelation temperature, rheological behaviour and micromorphology were measured. Vascular anastomosis were performed on the right common carotid arteries of rabbits, and the in vivo efficiency and safety of HP hydrogel to achieve vascular anastomosis was verified and compared with Poloxamer 407 hydrogel and the conventional hand-sewn method using Doppler ultrasound, CT angiograms, scanning electron microscopy (SEM and histological technique. Our results showed that HP copolymer displayed special gel-sol-gel phase transition behavior with increasing temperature from 5 to 60 °C. HP hydrogel prepared from 18 wt% HP solution had a porous sponge-like structure, with gelation temperature at approximately 38 °C and maximum elastic modulus at 10,000 Pa. In animal studies, imaging and histological examination of rabbit common jugular artery confirmed that HP hydrogel group had similar equivalent patency, flow and burst strength as Poloxamer 407 group. Moreover, HP hydrogel was superior to poloxamer 407 hydrogel and hand-sewn method for restoring the functions and epithelial structure of the broken vessel junctions after operation. By combining the advantages of heparin and poloxamer 407, HP hydrogel holds high promise for improving vascular anastomosis quality and safety.

  20. Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: part 1. Overview and lower extremity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sungjun [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Hanyang University, Kuri Hospital, Department of Diagnostic Radiology, College of Medicine, Kuri City, Kyunggi-do (Korea); Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Kim, Seung Min [Yonsei University, Department of Neurology, College of Medicine, Seoul (Korea); Suh, Jin-Suck [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Yonsei University, Research Institute of Radiological Science, College of Medicine, Seoul (Korea)

    2007-01-15

    The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the general concepts that should be known to evaluate the entrapment and compressive neuropathy in MR imaging. We also review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the lower extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the lower extremity are as follows: sciatic nerve around the piriformis muscle; tibial nerve at the popliteal fossa and tarsal tunnel, common peroneal nerve around the fibular neck, and digital nerve near the metatarsal head. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

  1. Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: part 1. Overview and lower extremity

    International Nuclear Information System (INIS)

    Kim, Sungjun; Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah; Kim, Seung Min; Suh, Jin-Suck

    2007-01-01

    The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the general concepts that should be known to evaluate the entrapment and compressive neuropathy in MR imaging. We also review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the lower extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the lower extremity are as follows: sciatic nerve around the piriformis muscle; tibial nerve at the popliteal fossa and tarsal tunnel, common peroneal nerve around the fibular neck, and digital nerve near the metatarsal head. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

  2. Microvascular anastomosis in rodent model evaluated by Fourier domain Doppler optical coherence tomography

    Science.gov (United States)

    Huang, Yong; Tong, Dedi; Zhu, Shan; Wu, Lehao; Ibrahim, Zuhaib; Lee, WP Andrew; Brandacher, Gerald; Kang, Jin U.

    2014-03-01

    Vascular and microvascular anastomosis are critical components of reconstructive microsurgery, vascular surgery and transplant surgery. Imaging modality that provides immediate, real-time in-depth view and 3D structure and flow information of the surgical site can be a great valuable tool for the surgeon to evaluate surgical outcome following both conventional and innovative anastomosis techniques, thus potentially increase the surgical success rate. Microvascular anastomosis for vessels with outer diameter smaller than 1.0 mm is extremely challenging and effective evaluation of the outcome is very difficult if not impossible using computed tomography (CT) angiograms, magnetic resonance (MR) angiograms and ultrasound Doppler. Optical coherence tomography (OCT) is a non-invasive high-resolution (micron level), high-speed, 3D imaging modality that has been adopted widely in biomedical and clinical applications. Phaseresolved Doppler OCT that explores the phase information of OCT signals has been shown to be capable of characterizing dynamic blood flow clinically. In this work, we explore the capability of Fourier domain Doppler OCT as an evaluation tool to detect commonly encountered post-operative complications that will cause surgical failure and to confirm positive result with surgeon's observation. Both suture and cuff based techniques were evaluated on the femoral artery and vein in the rodent model.

  3. Influence of applied compressive stress on the hysteresis curves and magnetic domain structure of grain-oriented transverse Fe-3%Si steel

    International Nuclear Information System (INIS)

    Perevertov, O; Schäfer, R

    2012-01-01

    The influence of an applied compressive stress on the hysteresis curve and domain structure in conventional (1 1 0) [0 0 1] Fe-3%Si steel cut transverse to the rolling direction is studied. Quasistatic hysteresis loops under compressive stress up to 75 MPa were measured. The magnetic domains and magnetization processes were observed by longitudinal Kerr microscopy at different levels of stress. It is shown that the bulk hysteresis loop can be described with a good accuracy by the action of an effective field, which is the product of the stress and a function of magnetization. Domain observations have shown that the reasons for the effective field are demagnetizing fields due to the disappearance of supplementary domains along [0 1 0] and [1 0 0] at low fields and different domain systems in different grains at moderate fields. The latter are caused by differences in grain sensitivity to stress depending on the degree of misorientation. A decrease in the effective field above 1 T is connected with a transformation of all grains into the same domain system—the column pattern. (paper)

  4. Experimental examination of the healing process of telescopic esophageal anastomosis.

    Science.gov (United States)

    Szücs, G; Tóth, I; Barna, T; Bráth, E; Gyáni, K; Mikó, I

    2003-01-01

    The basis of telescopic anastomosis is old, only the practical details of it have changed and improved. The telescopic anastomosis technique is successfully applied in our practice for reconstruction of gastrectomy and esophageal resection. The reason for this study was that data about the healing process of telescopic anastomosis had not been found in the literature. We used four groups of mongrel dogs for our experiments: Group A (n = 3) received 20 mm-long invaginations with a survival time of 7 days; Group B (n = 3) received 10 mm-long invaginations with a survival time of 21 days; Group C (n = 3) received 20 mm-long invaginations with a survival time of 21 days; Group D (n = 3) received 30 mm-long invaginations with a survival time of 21 days. At the end of the above survival times we removed the anastomosing area, measured the bursting pressures and performed morphological and histological examinations. In each case we also performed an anastomosis exactly the same as a completely healed anastomosis and its pressure tolerance was measured (0 day). The pressure tolerance within the anastomosis rises gradually and independently of the length of the invaginated esophageal part. Anastomosis leakage did not occur. The invaginated esophageal part did not suffer any damage. The muscular wall of the intragastric part of the esophagus became covered by the mucosa of the stomach during the healing process and it joined with the esophageal mucosa at the edge of the free end of the esophagus.

  5. Ureterocolonic anastomosis in clinically normal dogs

    International Nuclear Information System (INIS)

    Stone, E.A.; Walter, M.C.; Goldschmidt, M.H.; Biery, D.N.; Bovee, K.C.

    1988-01-01

    Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degress of metabolic acidosis, hyperammonemia, and neurologic disease may result

  6. Diagnosis of false proximal anastomosis aneurysms after aortofemoral reconstructive operations

    International Nuclear Information System (INIS)

    Pokrovskij, A.V.; Dan, V.N.; Karazeev, G.L.

    1993-01-01

    The paper deals with the diagnostic aspects of false aneurysms of proximal anastomosis of prostheses with the aorta on the basis of examination of 9 patients aged 3-65 years after aortofemoral reconstructive operations. The periods of the occurrence of false aneurysms were 2 weeks to 6 years. The causes of anastomosis aneurysms: infection, endartectomy fro the aorta at the site of applied anastomosis, progressive underlying disease. The authors provide strong evidence for a high informative value of various examinations, including ultrasound echoscanning, computer tomography, radioopaque aortography

  7. [Application of compression equipment using the "form memory" effect and super-elasticity of titanium nickelide in surgery for rectal cancer].

    Science.gov (United States)

    Vlasov, A A; Vazhenin, A V; Plotnikov, V V; Spirev, V V; Chinarev, Iu B

    2010-01-01

    The study is concerned with development of equipment for forming circular compression intestinal anastomosis using the "form memory" effect and super-elasticity of titanium nickelide. A sequence of technological operations is suggested, experimental tests and clinical trials carried out and immediate and end-results for anterior resection in rectal cancer are evaluated. Compression equipment for forming colorectal anastomosis proved reliable in long-term operation.

  8. Assessment of neurovascular compression in patients with trigeminal neuralgia with a boundary fusion three-dimensional magnetic resonance cisternogram/angiogram

    International Nuclear Information System (INIS)

    Satoh, Toru; Omi, Megumi; Ohsako, Chika; Onoda, Keisuke; Date, Isao

    2007-01-01

    Precise assessment of the complex nerve-vessel relationship at the root entry zone (REZ) of the trigeminal nerve is useful for the planning of the microvascular decompression (MVD) in patients with trigeminal neuralgia. We have applied a boundary imaging of fusion three-dimensional (3D) magnetic resonance (MR) cisternogram/angiogram. The boundary imaging allows virtual assessment of the spatial relationship of the neurovascular compression at the REZ of the trigeminal nerve. The boundary images depicted complex anatomical relationship of the offending vessels to the trigeminal nerve REZ. The presence of offending vessels, compressive site, and degree of neurovascular compression were assessed from various viewpoints in the cistern and virtually through the brainstem and trigeminal nerve per se. The 3D visualization of the nerve-vessel relationship with fusion images was consistent with the intraoperative findings. The boundary fusion 3D MR cisternogram/angiogram may prove a useful adjunct for the diagnosis and decision-marking process to execute the MVD in patients with trigeminal neuralgia. (author)

  9. Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: Part 2. Upper extremity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sungjun [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Hanyang University, Kuri Hospital, Department of Diagnostic Radiology, College of Medicine, Kuri City, Kyunggi-do (Korea); Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Kim, Seung Min [Yonsei University, Department of Neurology, College of Medicine, Seoul (Korea); Suh, Jin-Suck [Yonsei University, Department of Diagnostic Radiology, College of Medicine, Seoul (Korea); Yonsei University, Research Institute of Radiological Science, College of Medicine, Seoul (Korea)

    2007-02-15

    The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions, but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the upper extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the upper extremity are as follows: the brachial plexus of the thoracic outlet; axillary nerve of the quadrilateral space; radial nerve of the radial tunnel; ulnar nerve of the cubital tunnel and Guyon's canal; median nerve of the pronator syndrome, anterior interosseous nerve syndrome, and carpal tunnel syndrome. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

  10. Role of magnetic resonance imaging in entrapment and compressive neuropathy - what, where, and how to see the peripheral nerves on the musculoskeletal magnetic resonance image: Part 2. Upper extremity

    International Nuclear Information System (INIS)

    Kim, Sungjun; Choi, Jin-Young; Huh, Yong-Min; Song, Ho-Taek; Lee, Sung-Ah; Kim, Seung Min; Suh, Jin-Suck

    2007-01-01

    The diagnosis of nerve entrapment and compressive neuropathy has been traditionally based on the clinical and electrodiagnostic examinations. As a result of improvements in the magnetic resonance (MR) imaging modality, it plays not only a fundamental role in the detection of space-occupying lesions, but also a compensatory role in clinically and electrodiagnostically inconclusive cases. Although ultrasound has undergone further development in the past decades and shows high resolution capabilities, it has inherent limitations due to its operator dependency. We review the course of normal peripheral nerves, as well as various clinical demonstrations and pathological features of compressed and entrapped nerves in the upper extremities on MR imaging, according to the nerves involved. The common sites of nerve entrapment of the upper extremity are as follows: the brachial plexus of the thoracic outlet; axillary nerve of the quadrilateral space; radial nerve of the radial tunnel; ulnar nerve of the cubital tunnel and Guyon's canal; median nerve of the pronator syndrome, anterior interosseous nerve syndrome, and carpal tunnel syndrome. Although MR imaging can depict the peripheral nerves in the extremities effectively, radiologists should be familiar with nerve pathways, common sites of nerve compression, and common space-occupying lesions resulting in nerve compression in MR imaging. (orig.)

  11. Study of the microstructural evolution and rheological behavior by semisolid compression between parallel plate of the alloy A356 solidified under a continuously rotating magnetic field

    International Nuclear Information System (INIS)

    Leiva L, Ricardo; Sanchez V, Cristian; Mannheim C, Rodolfo; Bustos C, Oscar

    2004-01-01

    This work presents a study of the rheological behavior of the alloy A356, with and without continuous magnetic agitation during its solidification, in semisolid state. The evaluation was performed using a parallel plate compression rheometer with the digital recording of position and time data. The microstructural evolution was also studied at the start and end of the semisolid compression test. The procedure involved tests of short cylinders extracted from billets with a non dendritic microstructure cast under a continuously rotating magnetic field. These pieces were tested in different solid fractions, at constant charges and at constant deformation velocities. When the test is carried out at a constant charge the equation can be determined that governs the rheological behavior of the material in semisolid state following a power grade of two Ostwald-de-Waele parameters. But when the test is done at a constant deformation speed the flow behavior of the material can be described in the semisolid shaping process. The results obtained show that the morphology of the phases present in the microstructure is highly relevant to its rheological behavior. A globular coalesced rosette to rosette type microstructure was found to have the typical behavior of a fluid when shaped in a semisolid state but a cast dendritic structure did not behave this way. Also the Arrhenius type dependence of viscosity with temperature was established (CW)

  12. A STUDY OF FACTORS AFFECTING HEALING OF GASTROINTESTINAL TRACT ANASTOMOSIS

    OpenAIRE

    Anjani; Amit; Vikram Singh; Rajesh; Jalaj

    2014-01-01

    : Aim of this prospective study to identify the factor which affects the morbidity and mortality of gastrointestinal anastomosis. This prospective study was conducted in G.R. Medical College from November 2012 to October 2013. Our study plan was approved by Ethical Committee of our institute 80 patients were included in this study who underwent gastrointestinal anastomosis whether elective or emergency irrespective of age and gender. A detailed history and relevant preoper...

  13. Induced chorioretinal venous anastomosis in experimental retinal branch vein occlusion.

    OpenAIRE

    McAllister, I L; Yu, D Y; Vijayasekaran, S; Barry, C; Constable, I

    1992-01-01

    Iatrogenic retinal vein to choroidal vein anastomoses were created using laser photocoagulation in six of seven dog eyes in which a partial branch retinal vein occlusion had previously been created photochemically. A similar attempt to create an anastomosis was made in six control eyes in which no branch vein occlusion was present. In the eyes in which a branch retinal vein had been created, a venous chorioretinal anastomosis appeared to be present by 3 to 6 weeks. In three control eyes simil...

  14. Benefits of intracorporeal gastrointestinal anastomosis following laparoscopic distal gastrectomy

    Directory of Open Access Journals (Sweden)

    Lee Sang-Woong

    2012-12-01

    Full Text Available Abstract Background Laparoscopic gastrectomy has recently been gaining popularity as a treatment for cancer; however, little is known about the benefits of intracorporeal (IC gastrointestinal anastomosis with pure laparoscopic distal gastrectomy (LDG compared with extracorporeal (EC anastomosis with laparoscopy-assisted distal gastrectomy (LADG. Methods Between June 2000 and December 2011, we assessed 449 consecutive patients with early-stage gastric cancer who underwent LDG. The patients were classified into three groups according to the method of reconstruction LADG followed by EC hand-sewn anastomosis (LADG + EC (n = 73, using any of three anastomosis methods (Billroth-I (B-I, Billroth-II (B-II or Roux-en-Y (R-Y; LDG followed by IC B-I anastomosis (LDG + B-I (n = 248; or LDG followed by IC R-Y anastomosis (LDG + R-Y (n = 128. The analyzed parameters included patient and tumor characteristics, operation details, and post-operative outcomes. Results The tumor location was significantly more proximal in the LDG + R-Y group than in the LDG + B-I group (P P P  Conclusions Intracorporeal mechanical anastomosis by either the B-I or R-Y method following LDG has several advantages over at the LADG + EC, including small wound size, reduced invasiveness, and safe anastomosis. Although additional randomized control studies are warranted to confirm these findings, we consider that pure LDG is a useful technique for patients with early gastric cancer.

  15. Detection of compression vessels in trigeminal neuralgia by surface-rendering three-dimensional reconstruction of 1.5- and 3.0-T magnetic resonance imaging.

    Science.gov (United States)

    Shimizu, Masahiro; Imai, Hideaki; Kagoshima, Kaiei; Umezawa, Eriko; Shimizu, Tsuneo; Yoshimoto, Yuhei

    2013-01-01

    Surface-rendered three-dimensional (3D) 1.5-T magnetic resonance (MR) imaging is useful for presurgical simulation of microvascular decompression. This study compared the sensitivity and specificity of 1.5- and 3.0-T surface-rendered 3D MR imaging for preoperative identification of the compression vessels of trigeminal neuralgia. One hundred consecutive patients underwent microvascular decompression for trigeminal neuralgia. Forty and 60 patients were evaluated by 1.5- and 3.0-T MR imaging, respectively. Three-dimensional MR images were constructed on the basis of MR imaging, angiography, and venography data and evaluated to determine the compression vessel before surgery. MR imaging findings were compared with the microsurgical findings to compare the sensitivity and specificity of 1.5- and 3.0-T MR imaging. The agreement between MR imaging and surgical findings depended on the compression vessels. For superior cerebellar artery, 1.5- and 3.0-T MR imaging had 84.4% and 82.7% sensitivity and 100% and 100% specificity, respectively. For anterior inferior cerebellar artery, 1.5- and 3.0-T MR imaging had 33.3% and 50% sensitivity and 92.9% and 95% specificity, respectively. For the petrosal vein, 1.5- and 3.0-T MR imaging had 75% and 64.3% sensitivity and 79.2% and 78.1% specificity, respectively. Complete pain relief was obtained in 36 of 40 and 55 of 60 patients undergoing 1.5- and 3.0-T MR imaging, respectively. The present study showed that both 1.5- and 3.0-T MR imaging provided high sensitivity and specificity for preoperative assessment of the compression vessels of trigeminal neuralgia. Preoperative 3D imaging provided very high quality presurgical simulation, resulting in excellent clinical outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. The Effect of Infliximab on Intestinal Anastomosis Healing in Rats

    Directory of Open Access Journals (Sweden)

    Oktay Karaköse

    2016-01-01

    Full Text Available Intestinal anastomosis healing is a complex physiological process in which many local and systemic factors play a role. One of the significant cytokines in this process is TNF-α. Infliximab is a chimeric monoclonal antibody which binds to TNF-α with high affinity. Although this agent is used in ulcerative colitis and Crohn’s disease, intestinal surgery may be required in these patients. In this study it was aimed to determine whether or not there was any negative effect of preoperative single dose infliximab treatment on intestinal anastomosis healing. Two groups of 10 rats were formed. One of these groups was administered with a single dose of infliximab 8 mg/kg as a 20-minute intravenous infusion from the femoral vein. Four days after the infusion, a full layer incision was made to the colon and anastomosis was applied to all the rats. At 7 days after anastomosis, the subjects were sacrificed. The anastomosis segment was removed and the bursting pressure was measured. Tissue samples were taken from this segment for hydroxyproline concentration and histopathological examination. A blood sample was taken to measure TNF-α values. No statistically significant difference was determined between the groups in terms of bursting pressure, tissue hydroxyproline concentration or histopathological scoring. A single dose of 8 mg/kg infliximab administered 4 days preoperatively was not found to have any negative effect on intestinal anastomosis healing in rats.

  17. Global solvability, non-resistive limit and magnetic boundary layer of the compressible heat-conductive MHD equations

    OpenAIRE

    Zhang, Jianwen; Zhao, Xiaokui

    2015-01-01

    In general, the resistivity is inversely proportional to the electrical conductivity, and is usually taken to be zero when the conducting fluid is of extremely high conductivity (e.g., ideal conductors). In this paper, we first establish the global well-posedness of strong solution to an initial-boundary value problem of the one-dimensional compressible, viscous, heat-conductive, non-resistive MHD equations with general heat-conductivity coefficient and large data. Then, the non-resistive lim...

  18. Murine Ileocolic Bowel Resection with Primary Anastomosis

    Science.gov (United States)

    Perry, Troy; Borowiec, Anna; Dicken, Bryan; Fedorak, Richard; Madsen, Karen

    2014-01-01

    Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn’s disease and colon cancer being two common examples. Despite the frequency of these procedures, a significant knowledge gap remains in describing the inherent effects of intestinal resection on host physiology and disease pathophysiology. This article provides detailed instructions for an ileocolic resection with primary end-to-end anastomosis in mice, as well as essential aspects of peri-operative care to maximize post-operative success. When followed closely, this procedure yields a 95% long-term survival rate, no failure to thrive, and minimizes post-operative complications of bowel obstruction and anastomotic leak. The technical challenges of performing the procedure in mice are a barrier to its wide spread use in research. The skills described in this article can be acquired without previous surgical experience. Once mastered, the murine ileocolic resection procedure will provide a reproducible tool for studying the effects of intestinal resection in models of human disease. PMID:25406841

  19. DNABIT Compress - Genome compression algorithm.

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-22

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, "DNABIT Compress" for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that "DNABIT Compress" algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases.

  20. Compression stockings

    Science.gov (United States)

    Call your health insurance or prescription plan: Find out if they pay for compression stockings. Ask if your durable medical equipment benefit pays for compression stockings. Get a prescription from your doctor. Find a medical equipment store where they can ...

  1. Effect of omentum graft on esophageal anastomosis in dogs

    Directory of Open Access Journals (Sweden)

    A. K. Mahdi

    2011-01-01

    Full Text Available The aim of this study was to evaluate the complications and final function outcome of wrapping nonvascularized omentum graft around the suture line of esophageal anastomosis. Twelve adult local breed dogs were used in this study. The animals were divided into two equal groups (control and treated, all animal induced into general anesthesia by injection of atropen sulphate in a dose 0.04 mg/kg B.W, intramuscularly then after 15 minute given mixture of ketamine hydrochloride and xylazine hydrochloride in doses 15 mg/kg and 5 mg/kg B.W intramuscularly respectively. An oblique resection of about 1cm of the esophageal length and anastomosis by double layer of simple interrupted pattern by 2.0 cat gut suture (control group, same procedure was done in treated group except the wrapping the anastomosis site with patch of omentum tissue after lapratomy operation in the left flank region procedure. The clinical signs of treated animal revealed signs of dysphagia and regurgitation in treated group while this signs disappear in the control group. Radiological and histopathological examination of the anastomosis site performed at 15 and 30 days post operation. Radiological study recorded high degree of stenosis in the anastomosis site in treated group at 15 and 30 days post operation in compared with animals in control group that record mean degree of stenosis in treated group at 15 day (57.61±0.2 and at 30 day (55.78±0.2 while it recorded in control group at 15 day (39.34±1.04 and at 30 day (36.0.6 ±0.9, histopathological results recorded enhanced healing of anastomosis site in treated animals more than control animals. In conclusion we found that non vascularized omental graft prevent leak when used around the anastomosis line in esophageal and enhanced healing of anastomosis line but it increase the stenosis, fibrosis and adhesion of anastomosis site with surrounding muscle and this interferes with the swallowing as well as dysphagia and regurgitation

  2. Microvascular Anastomosis Training in Neurosurgery: A Review

    Directory of Open Access Journals (Sweden)

    Vadim A. Byvaltsev

    2018-01-01

    Full Text Available Cerebrovascular diseases are among the most widespread diseases in the world, which largely determine the structure of morbidity and mortality rates. Microvascular anastomosis techniques are important for revascularization surgeries on brachiocephalic and carotid arteries and complex cerebral aneurysms and even during resection of brain tumors that obstruct major cerebral arteries. Training in microvascular surgery became even more difficult with less case exposure and growth of the use of endovascular techniques. In this text we will briefly discuss the history of microvascular surgery, review current literature on simulation models with the emphasis on their merits and shortcomings, and describe the views and opinions on the future of the microvascular training in neurosurgery. In “dry” microsurgical training, various models created from artificial materials that simulate biological tissues are used. The next stage in training more experienced surgeons is to work with nonliving tissue models. Microvascular training using live models is considered to be the most relevant due to presence of the blood flow. Training on laboratory animals has high indicators of face and constructive validity. One of the future directions in the development of microsurgical techniques is the use of robotic systems. Robotic systems may play a role in teaching future generations of microsurgeons. Modern technologies allow access to highly accurate learning environments that are extremely similar to real environment. Additionally, assessment of microsurgical skills should become a fundamental part of the current evaluation of competence within a microneurosurgical training program. Such an assessment tool could be utilized to ensure a constant level of surgical competence within the recertification process. It is important that this evaluation be based on validated models.

  3. Resection and anastomosis of the descending colon in 43 horses.

    Science.gov (United States)

    Prange, Timo; Holcombe, Susan J; Brown, Jennifer A; Dechant, Julie E; Fubini, Susan L; Embertson, Rolf M; Peroni, John; Rakestraw, Peter C; Hauptman, Joe G

    2010-08-01

    To determine (1) the short- (to hospital discharge) and long- (>6 months) term survival, (2) factors associated with short-term survival, and (3) the perioperative course for horses with resection and anastomosis of the descending colon. Multicentered case series. Horses (n=43) that had descending colon resection and anastomosis. Medical records (January 1995-June 2009) of 7 equine referral hospitals were reviewed for horses that had descending colon resection and anastomosis and were recovered from anesthesia. Retrieved data included history, results of clinical and clinicopathologic examinations, surgical findings, postsurgical treatment and complications, and short-term survival (hospital discharge). Long-term survival was defined as survival > or =6 months after hospital discharge. Of 43 horses, 36 (84%) were discharged from the hospital. Twenty-eight of 30 horses with follow-up information survived > or =6 months. No significant associations between perioperative factors and short-term survival were identified. Lesions included strangulating lipoma (n=27), postfoaling trauma (4), infarction (4), intraluminal obstruction (2), and other (6). Common postoperative complications included fever and diarrhea. During hospitalization 7 horses were euthanatized or died because of septic peritonitis (3), endotoxemia (3), and colic and ileus (1). Descending colon resection and anastomosis has a favorable prognosis for hospital discharge and survival > or =6 months. The most common cause of small colon incarceration was strangulating lipoma. Complications include postoperative fever and diarrhea but the prognosis is good after small colon resection and anastomosis.

  4. Granulocyte migration in uncomplicated intestinal anastomosis in man

    Energy Technology Data Exchange (ETDEWEB)

    Keshavarzian, A.; Gibson, R.; Guest, J.; Spencer, J.; Lavender, J.P.; Hodgson, H.J.

    1986-03-01

    We have investigated the presence, duration, and clinical significance of granulocyte accumulation, using indium-111 granulocyte scanning, in patients following uncomplicated intestinal anastomosis. Eight patients underwent intestinal resection and anastomosis (right hemicolectomy, 5; sigmoid colectomy, 2; ileal resection, 1) for carcinoma, angiodysplasia, or perforation. All patients had an uneventful postoperative course, with no evidence of any leakage or infection. Indium-111 granulocyte scan and abdominal ultrasound were performed 7-20 days (12 +/- 4.7 means +/- SD) following surgery. Indium-111 granulocyte scan showed the presence of labeled granulocytes at the site of anastomosis in all patients. In three of eight, cells subsequently passed into the lumen of the bowel. In contrast, granulocytes were not visualized along the abdominal incision. Thus, in contrast to skin wounds, granulocytes continue migrating into the intestinal wall in areas of anastomosis for at least up to 20 days following surgical trauma. They may play a significant role both in healing the anastomosis and in preventing systemic bacterial infection. Moreover, indium-111 granulocyte scans following intestinal surgery should be interpreted with care, and the presence of labeled granulocytes around anastomoses does not necessarily indicate abscess formation.

  5. Granulocyte migration in uncomplicated intestinal anastomosis in man

    International Nuclear Information System (INIS)

    Keshavarzian, A.; Gibson, R.; Guest, J.; Spencer, J.; Lavender, J.P.; Hodgson, H.J.

    1986-01-01

    We have investigated the presence, duration, and clinical significance of granulocyte accumulation, using indium-111 granulocyte scanning, in patients following uncomplicated intestinal anastomosis. Eight patients underwent intestinal resection and anastomosis (right hemicolectomy, 5; sigmoid colectomy, 2; ileal resection, 1) for carcinoma, angiodysplasia, or perforation. All patients had an uneventful postoperative course, with no evidence of any leakage or infection. Indium-111 granulocyte scan and abdominal ultrasound were performed 7-20 days (12 +/- 4.7 means +/- SD) following surgery. Indium-111 granulocyte scan showed the presence of labeled granulocytes at the site of anastomosis in all patients. In three of eight, cells subsequently passed into the lumen of the bowel. In contrast, granulocytes were not visualized along the abdominal incision. Thus, in contrast to skin wounds, granulocytes continue migrating into the intestinal wall in areas of anastomosis for at least up to 20 days following surgical trauma. They may play a significant role both in healing the anastomosis and in preventing systemic bacterial infection. Moreover, indium-111 granulocyte scans following intestinal surgery should be interpreted with care, and the presence of labeled granulocytes around anastomoses does not necessarily indicate abscess formation

  6. Laparoscopic anterior resection: new anastomosis technique in a pig model.

    Science.gov (United States)

    Bedirli, Abdulkadir; Yucel, Deniz; Ekim, Burcu

    2014-01-01

    Bowel anastomosis after anterior resection is one of the most difficult tasks to perform during laparoscopic colorectal surgery. This study aims to evaluate a new feasible and safe intracorporeal anastomosis technique after laparoscopic left-sided colon or rectum resection in a pig model. The technique was evaluated in 5 pigs. The OrVil device (Covidien, Mansfield, Massachusetts) was inserted into the anus and advanced proximally to the rectum. A 0.5-cm incision was made in the sigmoid colon, and the 2 sutures attached to its delivery tube were cut. After the delivery tube was evacuated through the anus, the tip of the anvil was removed through the perforation. The sigmoid colon was transected just distal to the perforation with an endoscopic linear stapler. The rectosigmoid segment to be resected was removed through the anus with a grasper, and distal transection was performed. A 25-mm circular stapler was inserted and combined with the anvil, and end-to-side intracorporeal anastomosis was then performed. We performed the technique in 5 pigs. Anastomosis required an average of 12 minutes. We observed that the proximal and distal donuts were completely removed in all pigs. No anastomotic air leakage was observed in any of the animals. This study shows the efficacy and safety of intracorporeal anastomosis with the OrVil device after laparoscopic anterior resection.

  7. Gastroesophageal anastomosis: single-layer versus double-layer technique

    International Nuclear Information System (INIS)

    Aslam, V.A.; Bilal, A.; Khan, A.; Ahmed, M.

    2008-01-01

    Considerable controversy exists regarding the optimum technique for gastroesophageal anastomosis. Double layer technique has long been considered important for safe healing but there is evidence that single layer technique is also safe and can be performed in much shorter time. The purpose of this study was to compare the outcome of single layer and double layer techniques for gastroesophageal anastomosis. A prospective randomized study was conducted in cardiothoracic unit, Lady Reading Hospital from Jan 2006 to Jan 2008. Fifty patients with oesophageal carcinoma undergoing subtotal oesophagectomy were randomized to have the anastomosis by single layer continuous or double layer continuous technique (group A (n=24) and B (n=26) respectively). The demographic data, operative and anastomosis time, postoperative complications and hospital mortality were recorded on a proforma and analyzed on SPSS 10. There was no significant difference between group A and B in terms of age, gender, postoperative complications and duration of hospital stay. Anastomotic leak occurred in 4.2% patients in group A and 7.7% in group B (p=NS). Mean anastomosis time was 10.04 minutes in group A and 19.2 minutes in group B (p=0.0001). Mean operative time was 163.83 minutes and 170.96 minutes in group A and B respectively. Overall hospital mortality was 2%; no deaths occurred due to anastomotic leak. Single layer continuous technique is equally safe and can be performed in shorter time and at a lower cost than the double layer technique. (author)

  8. Rupture of vesicourethral anastomosis following radical retropubic prostatectomy

    Directory of Open Access Journals (Sweden)

    Marcos Dall'oglio

    2003-06-01

    Full Text Available OBJECTIVE: Rupture of vesicourethral anastomosis following radical retropubic prostatectomy is a complication that requires immediate management. We evaluated the morbidity of this rare complication. MATERIALS AND METHODS: We analyzed retrospectively 5 cases of disruption of vesicourethral anastomosis during post-operative period in a consecutive series of 1,600 radical retropubic prostatectomies, performed by a single surgeon. RESULTS: It occurred in a ratio of 1:320 prostatectomies (0,3%. Management was conservative in all the cases with an average catheter permanence time of 28 days, being its removal preceded by cystography. Two cases were secondary to bleeding, 1 followed the change of vesical catheter and 2 by unknown causes after removing the Foley catheter. Only one patient evolved with urethral stenosis, in the period ranging from 6 to 120 months. CONCLUSION: Rupture of vesicourethral anastomosis is not related to the surgeon's experience, and conservative treatment has shown to be effective.

  9. Fingertip replantations: importance of venous anastomosis and the clinical results.

    Science.gov (United States)

    Hasuo, Takaaki; Nishi, Genzaburo; Tsuchiya, Daiji; Otsuka, Takanobu

    2009-01-01

    Overall survival rate for 143 digits with complete amputation of the distal phalanx was 78%. Replanted digits that underwent venous anastomosis showed a very high survival rate of 93%. Loss of the distal interphalangeal joint function in subzone IV was significantly inferior to that in subzones II and III. Protective sensation was achieved in 96% of replanted digits. Sensory recovery in the absence of nerve repair was significantly worse for avulsion injury than for crush injury. Nail deformity tended to be increased for replanted digits in subzone III or with crush-type injury. Successful venous anastomosis appears to offer the best way to promote survival of replanted digits. If venous anastomosis is infeasible, a replanted digit can survive with any methods for venous drainage in subzones II and III, but does not survive in subzone IV. To minimise nail deformity, repair of the germinal matrix is necessary.

  10. Effects of JPEG data compression on magnetic resonance imaging evaluation of small vessels ischemic lesions of the brain; Efeitos da compressao de dados JPEG na avaliacao de lesoes vasculares cerebrais isquemicas de pequenos vasos em ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Kuriki, Paulo Eduardo de Aguiar; Abdala, Nitamar; Nogueira, Roberto Gomes; Carrete Junior, Henrique; Szejnfeld, Jacob [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: paulokuriki@gmail.com

    2006-01-15

    Objective: to establish the maximum achievable JPEG compression ratio without affecting quantitative and qualitative magnetic resonance imaging analysis of ischemic lesion in small vessels of the brain. Material and method: fifteen DICOM images were converted to JPEG with a compression ratio of 1:10 to 1:60 and were assessed together with the original images by three neuro radiologists. The number, morphology and signal intensity of the lesions were analyzed. Results: lesions were properly identified up to a 1:30 ratio. More lesions were identified with a 1:10 ratio then in the original images. Morphology and edges were properly evaluated up toa 1:40 ratio. Compression did not affect signal. Conclusion: small lesions were identified ( < 2 mm ) and in all compression ratios the JPEG algorithm generated image noise that misled observers to identify more lesions in JPEG images then in DICOM images, thus generating false-positive results.(author)

  11. Niti CAR 27 Versus a Conventional End-to-End Anastomosis Stapler in a Laparoscopic Anterior Resection for Sigmoid Colon Cancer

    Science.gov (United States)

    Kwag, Seung-Jin; Kim, Jun-Gi; Kang, Won-Kyung; Lee, Jin-Kwon

    2014-01-01

    Purpose The Niti CAR 27 (ColonRing) uses compression to create an anastomosis. This study aimed to investigate the safety and the effectiveness of the anastomosis created with the Niti CAR 27 in a laparoscopic anterior resection for sigmoid colon cancer. Methods In a single-center study, 157 consecutive patients who received an operation between March 2010 and December 2011 were retrospectively assessed. The Niti CAR 27 (CAR group, 63 patients) colorectal anastomoses were compared with the conventional double-stapled (CDS group, 94 patients) colorectal anastomoses. Intraoperative, immediate postoperative and 6-month follow-up data were recorded. Results There were no statistically significant differences between the two groups in terms of age, gender, tumor location and other clinical characteristics. One patient (1.6%) in the CAR group and 2 patients (2.1%) in the CDS group experienced complications of anastomotic leakage (P = 0.647). These three patients underwent a diverting loop ileostomy. There were 2 cases (2.1%) of bleeding at the anastomosis site in the CDS group. All patients underwent a follow-up colonoscopy (median, 6 months). One patient in the CAR group experienced anastomotic stricture (1.6% vs. 0%; P = 0.401). This complication was solved by using balloon dilatation. Conclusion Anastomosis using the Niti CAR 27 device in a laparoscopic anterior resection for sigmoid colon cancer is safe and feasible. Its use is equivalent to that of the conventional double-stapler. PMID:24851217

  12. Tracheal growth after resection and anastomosis in puppies.

    Science.gov (United States)

    Blanchard, H; Brochu, P; Bensoussan, A L; Lagacé, G; Khan, A H

    1986-09-01

    Tracheal morphology, morphometric changes, and growth and histologic changes were studied in puppies submitted to tracheal resection and anastomosis. Fifteen mongrel puppies about 12 weeks old and weighing on an average 5.5 kg were operated under general anesthesia using fluothane. A median cervicotomy incision was made in ten puppies (experimental group, EG) and the proximal 14 tracheal rings were resected (average length 5.08 cm or about 35% to 38% of total tracheal length). One layer anastomosis was done using vicryl 4.0 maintaining the average tension of 1,450 g. Five puppies (control group, CG) were submitted to tracheal transection and anastomosis and the following parameters were studied. Tracheal morphology the trachea of the EG was a rounded triangle whereas in the CG it was oval in shape, there was increase in the intercartilageneous spaces in the EG, no granulation tissue was present, two mucous webs were seen in the EG and one in the CG. Morphometric changes average tracheal length EG 13 cm, CG 17.7 cm, intercartilagenous space EG 3.08 mm, CG 1.3 mm, intercricothyroid space EG 1.2 cm, CG 0.53 cm, sagittal and transverse tracheal thickness at the anastomosis EG 2.6 and 3.3 mm, CG 2 and 1.5 mm, sagittal and transverse diameter reduced on an average 2 mm in EG. Histology Moderate fibrosis was found at the level of anastomosis with no modification of chondrocytes at the cartilagenous rings in the EG. Even with high anastomotic tension, the dogs had normal tracheal growth without stenosis; the sagittal and transverse growth at the anastomosis in the EG was 90% and 85%, respectively, when compared with the CG.

  13. Microsurgical Bypass Training Rat Model: Part 2-Anastomosis Configurations.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Lawton, Michael T; Yousef, Sonia; Mokhtari, Pooneh; Gandhi, Sirin; Benet, Arnau

    2017-11-01

    Mastery of microsurgical anastomosis is key to achieving good outcomes in cerebrovascular bypass procedures. Animal models (especially rodents) provide an optimal preclinical bypass training platform. However, the existing models for practicing different anastomosis configurations have several limitations. We sought to optimize the use of the rat's abdominal aorta and common iliac arteries (CIA) for practicing the 3 main anastomosis configurations commonly used in cerebrovascular surgery. Thirteen male Sprague-Dawley rats underwent inhalant anesthesia. The abdominal aorta and the CIAs were exposed. The distances between the major branches of the aorta were measured to find the optimal location for an end-to-end anastomosis. Also, the feasibility of performing side-to-side and end-to-side anastomoses between the CIAs was assessed. All bypass configurations could be performed between the left renal artery and the CIA bifurcation. The longest segments of the aorta without major branches were 1) between the left renal and left iliolumbar arteries (16.9 mm ± 4.6), and 2) between the right iliolumbar artery and the aortic bifurcation (9.7 mm ± 4.7). The CIAs could be juxtaposed for an average length of 7.6 mm ± 1.3, for a side-to-side anastomosis. The left CIA could be successfully reimplanted on to the right CIA at an average distance of 9.1 mm ± 1.6 from the aortic bifurcation. Our results show that rat's abdominal aorta and CIAs may be effectively used for all the anastomosis configurations used in cerebral revascularization procedures. We also provide technical nuances and anatomic descriptions to plan for practicing each bypass configuration. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Use of a circular stapler for Billroth I anastomosis after distal ...

    African Journals Online (AJOL)

    2013-11-04

    Nov 4, 2013 ... linear staplers. Takeuchi et al.[3] then reported the first gastroduodenal anastomosis using one circular and one linear stapler. This technique has also been effectively used for Billroth II anastomosis.[4] We established gastroduodenal anastomosis using the circular stapler before resection of the stomach ...

  15. Radiation-induced myelopathy in long-term surviving metastatic spinal cord compression patients after hypofractionated radiotherapy: a clinical and magnetic resonance imaging analysis

    International Nuclear Information System (INIS)

    Maranzano, Ernesto; Bellavita, Rita; Floridi, Piero; Celani, Grazia; Righetti, Enrico; Lupattelli, Marco; Panizza, Bianca Moira; Frattegiani, Alessandro; Pelliccioli, Gian Piero; Latini, Paolo

    2001-01-01

    Background and purpose: Hypofractionated radiotherapy is often administered in metastatic spinal cord compression (MSCC), but no studies have been published on the incidence of radiation-induced myelopathy (RIM) in long-term surviving patients. Our report addresses this topic. Patients and methods: Of 465 consecutive MSCC patients submitted to radiotherapy between 1988 and 1997, 13 live patients (seven females, six males, median age 69 years, median follow-up 69 months) surviving for 2 years or more were retrospectively reviewed to evaluate RIM. All patients underwent radiotherapy. Eight patients underwent a short-course regimen of 8 Gy, with 7 days rest, and then another 8 Gy. Five patients underwent a split-course regimen of 5 Gy x3, 4 days rest, and then 3 Gy x5. Only one patient also underwent laminectomy. Full neurological examination and magnetic resonance imaging (MRI) were performed. Results: Of 12 patients submitted to radiotherapy alone, 11 were ambulant (eight without support and three with support) with good bladder function. In nine of these 11 patients, MRI was negative; in one case MRI evidenced an in-field relapse 30 months after the end of radiotherapy, and in the other, two new MSCC foci outside the irradiated spine. In the remaining patient RIM was suspected at 18 months after radiotherapy when the patient became paraplegic and cystoplegic, and magnetic resonance images evidenced an ischemic injury in the irradiated area. The only patient treated with surgery plus postoperative radiotherapy worsened and remained paraparetic. Magnetic resonance images showed cord atrophy at the surgical level, explained as an ischemic necrosis due to surgery injury. Conclusions: On the grounds of our data regarding RIM in long-term surviving MSCC patients, we believe that a hypofractionated radiotherapy regimen can be used for the majority of patients. For a minority of patients, more protracted radiation regimens could be considered

  16. Neuroanatomical study of Galen's anastomosis (nervus laryngeus) in the dog.

    Science.gov (United States)

    Henry, C; Cazals, Y; Gioux, M; Didier, A; Aran, J M; Traissac, L

    1988-01-01

    To further knowledge of the laryngeal nerves, the nerve fibers of Galen's anastomosis were studied using two neuroanatomical methods, namely nerve degeneration and horseradish peroxidase labeling. It is demonstrated that the superior laryngeal nerve forms part of the tracheal and esophageal nervous system. The value of the results in relation to physiological laryngeal studies and to human laryngeal diseases is discussed.

  17. Hepaticoduodenostomy as a technique for biliary anastomosis in ...

    African Journals Online (AJOL)

    Hepaticoduodenostomy as a technique for biliary anastomosis in children with choledochal cyst: ... anastomotic technique in cases of choledochal cyst in children. Ann Pediatr Surg 13:78–80 c 2017 .... versus hepaticojejunostomy after resection of choledochal cyst: a systematic review and meta-analysis. J Pediatr Surg ...

  18. Surgery for necrotising enterocolitis : primary anastomosis or enterostomy?

    NARCIS (Netherlands)

    Hofman, FN; Bax, NMA; van der Zee, DC

    The ideal surgical management of neonates with necrotising enterocolitis (NEC) is still a matter of debate. The purpose of this study was to compare the results of bowel resection with primary anastomosis with the results of bowel resection with enterostomy. Sixty-three neonates with NEC had a bowel

  19. Comparison between strictureplasty and resection anastomosis in tuberculous intestinal strictures

    International Nuclear Information System (INIS)

    Zafar, A.; Qureshi, A.M.; Iqbal, M.

    2003-01-01

    Objective: To compare the effectiveness, safety and morbidity of strictureplasty with resection anastomosis in patients with tuberculous small gut strictures. Subjects and Methods: Thirty patients who presented with intestinal obstruction due to tuberculous strictures, and underwent either resection anastomosis or strictureplasty where included in the study. Data was collected on a proforma and analyzed using software SPSS (version 8.0). Chi-square and t-test were used to test the hypothesis. Main outcome measures included the presence or absence of postoperative leakage anastomosis, wound infection, recurrence of intestinal obstruction and postoperative study. Results: Chi-square test applied to see the effectiveness showed no significant difference (p>0.5) between the two procedures. t-Test on the score of morbidity also showed no significant difference (p>0.5) between the two procedures. Conclusion: Both procedures performed were equally effective and had equal morbidity in cases of intestinal tuberculous strictures. Strictureplasty is superior to resection anastomosis in cases of multiple strictures as it conserves gut length and can even be performed safely in cases with coexistent gut perforation. (author)

  20. Hypoglossal-facial-jump-anastomosis without an interposition nerve graft.

    Science.gov (United States)

    Beutner, Dirk; Luers, Jan C; Grosheva, Maria

    2013-10-01

    The hypoglossal-facial-anastomosis is the most often applied procedure for the reanimation of a long lasting peripheral facial nerve paralysis. The use of an interposition graft and its end-to-side anastomosis to the hypoglossal nerve allows the preservation of the tongue function and also requires two anastomosis sites and a free second donor nerve. We describe the modified technique of the hypoglossal-facial-jump-anastomosis without an interposition and present the first results. Retrospective case study. We performed the facial nerve reconstruction in five patients. The indication for the surgery was a long-standing facial paralysis with preserved portion distal to geniculate ganglion, absent voluntary activity in the needle facial electromyography, and an intact bilateral hypoglossal nerve. Following mastoidectomy, the facial nerve was mobilized in the fallopian canal down to its bifurcation in the parotid gland and cut in its tympanic portion distal to the lesion. Then, a tensionless end-to-side suture to the hypoglossal nerve was performed. The facial function was monitored up to 16 months postoperatively. The reconstruction technique succeeded in all patients: The facial function improved within the average time period of 10 months to the House-Brackmann score 3. This modified technique of the hypoglossal-facial reanimation is a valid method with good clinical results, especially in cases of a preserved intramastoidal facial nerve. Level 4. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  1. The entire dural sinus tree is compressed in patients with idiopathic intracranial hypertension: a longitudinal, volumetric magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Rohr, Axel; Bindeballe, Jan; Riedel, Christian; Jansen, Olav [University Clinic of Schleswig-Holstein Campus Kiel, Department of Neuroradiology, Kiel (Germany); Baalen, Andreas van [University Clinic of Schleswig-Holstein Campus Kiel, Department of Neuropediatrics, Kiel (Germany); Bartsch, Thorsten [University Clinic of Schleswig-Holstein Campus Kiel, Department of Neurology, Kiel (Germany); Doerner, Lutz [University Clinic of Schleswig-Holstein Campus Kiel, Department of Neurosurgery, Kiel (Germany)

    2012-01-15

    The objective of this study was to explore the volumetric alterations of dural sinuses in patients with idiopathic intracranial hypertension (IIH). Standardized cranial magnetic resonance imaging (MRI) was used in 17 patients prior to and following treatment of IIH and in seven controls. Magnetic resonance venographies (MRV) were employed for (a) judgement of circumscript dural sinus stenoses and (b) computation of sinus volumes. Cross-sectional areas (CSA) of the superior sagittal sinuses (SSS) were measured on T2-weighted images. Results of the initial MRIs were compared to those on follow-up MRIs and to results of controls. Stenoses of the transverse sinuses (TS) resulting in cranial venous outflow obstruction (CVOO) were present in 15/17 (88%) patients, normalizing in 7/15 cases (47%) after treatment of IIH. CVOO was not detected in the control group. Segmentation of MRV revealed decreased dural sinus volumes in patients with IIH as compared to controls (P = 0.018). Sinus volumes increased significantly with normalization of intracranial pressure independent from disappearing of TS stenoses (P = 0.007). The CSA of the SSS were normal on the initial MRIs of patients with IIH and increased on follow-up after treatment (P < 0.001). However, volumetries displayed overlap in patients and controls. Patients with IIH not only exhibit bilateral stenoses of the TS as has been reported, but volume changes of their entire dural sinus system also occur. The potential etiopathological and diagnostic roles of these changes are discussed. (orig.)

  2. Compressive neuropathy of the first branch of the lateral plantar nerve: a study by magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Rogéria Nobre Rodrigues

    2015-12-01

    Full Text Available Abstract Objective: To assess the prevalence of isolated findings of abnormalities leading to entrapment of the lateral plantar nerve and respective branches in patients complaining of chronic heel pain, whose magnetic resonance imaging exams have showed complete selective fatty atrophy of the abductor digiti quinti muscle. Materials and Methods: Retrospective, analytical, and cross-sectional study. The authors selected magnetic resonance imaging of hindfoot of 90 patients with grade IV abductor digiti quinti muscle atrophy according to Goutallier and Bernageau classification. Patients presenting with minor degrees of fatty muscle degeneration (below grade IV and those who had been operated on for nerve decompression were excluded. Results: A female prevalence (78.8% was observed, and a strong correlation was found between fatty muscle atrophy and plantar fasciitis in 21.2%, and ankle varices, in 16.8% of the patients. Conclusion: Fatty atrophy of the abductor digiti quinti muscle is strongly associated with neuropathic alterations of the first branch of the lateral plantar nerve. The present study showed a significant association between plantar fasciitis and ankle varices with grade IV atrophy of the abductor digiti quinti muscle.

  3. MARTIN–GRUBER ANASTOMOSIS AND ITS CLINICAL IMPORTANCE

    Directory of Open Access Journals (Sweden)

    I. G. Mikhaylyuk

    2015-01-01

    Full Text Available The communication between the median and ulnar nerves on the forearm, known as the Martin–Gruber anastomosis, is widespread in the general population. Despite the fact that this connection is described by anatomists in XVIII century, its importance has only recently been appreciated because of the widespread of the electrophysiological techniques in clinical practies. However, in the Russian literature aspects of its practical value described so far is not enough. This article deals with the prevalence of the anastomosis, its anatomical and electrophysiological classification, options innervation of muscles of the hand, is carried out through him, described electrophysiological methods and criteria for its diagnosis, including the collision technique, in healthy subjects and patients with lesions of the median and ulnar nerves, given its practical value. Such a course of nerve fibers through this anastomosis can have a significant impact on the clinical manifestations in patients with lesions of the median and ulnar nerves, as well as the results of an electrophysiological study. Martin–Gruber anastomosis provides variability innervation muscles of the hand, which can make it difficult topic diagnostic damage to the median and ulnar nerves, in addition, because of the connection between the nerves of the clinical presentation may not reflect the extent of their defeat: the hand muscles function can be preserved with full nerve damage or, conversely, significantly disrupted with minimal nerve lesions. Moreover, different electrophysiological findings on patients with pathology of the median or ulnar nerves in the conditions of functioning anastomosis may also complicate the interpretation of the clinical data. Thus, knowledge of the anatomy and physiology of the Martin–Gruber communication as necessary for the electrophysiologist for correct interpretation of the finding and the clinician to accurately diagnose the pathology of the median

  4. Compressive sensing in medical imaging.

    Science.gov (United States)

    Graff, Christian G; Sidky, Emil Y

    2015-03-10

    The promise of compressive sensing, exploitation of compressibility to achieve high quality image reconstructions with less data, has attracted a great deal of attention in the medical imaging community. At the Compressed Sensing Incubator meeting held in April 2014 at OSA Headquarters in Washington, DC, presentations were given summarizing some of the research efforts ongoing in compressive sensing for x-ray computed tomography and magnetic resonance imaging systems. This article provides an expanded version of these presentations. Sparsity-exploiting reconstruction algorithms that have gained popularity in the medical imaging community are studied, and examples of clinical applications that could benefit from compressive sensing ideas are provided. The current and potential future impact of compressive sensing on the medical imaging field is discussed.

  5. Non-Destructive Detection of Wire Rope Discontinuities from Residual Magnetic Field Images Using the Hilbert-Huang Transform and Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Juwei Zhang

    2017-03-01

    Full Text Available Electromagnetic methods are commonly employed to detect wire rope discontinuities. However, determining the residual strength of wire rope based on the quantitative recognition of discontinuities remains problematic. We have designed a prototype device based on the residual magnetic field (RMF of ferromagnetic materials, which overcomes the disadvantages associated with in-service inspections, such as large volume, inconvenient operation, low precision, and poor portability by providing a relatively small and lightweight device with improved detection precision. A novel filtering system consisting of the Hilbert-Huang transform and compressed sensing wavelet filtering is presented. Digital image processing was applied to achieve the localization and segmentation of defect RMF images. The statistical texture and invariant moment characteristics of the defect images were extracted as the input of a radial basis function neural network. Experimental results show that the RMF device can detect defects in various types of wire rope and prolong the service life of test equipment by reducing the friction between the detection device and the wire rope by accommodating a high lift-off distance.

  6. Simple motion correction strategy reduces respiratory-induced motion artifacts for k-t accelerated and compressed-sensing cardiovascular magnetic resonance perfusion imaging.

    Science.gov (United States)

    Zhou, Ruixi; Huang, Wei; Yang, Yang; Chen, Xiao; Weller, Daniel S; Kramer, Christopher M; Kozerke, Sebastian; Salerno, Michael

    2018-02-01

    Cardiovascular magnetic resonance (CMR) stress perfusion imaging provides important diagnostic and prognostic information in coronary artery disease (CAD). Current clinical sequences have limited temporal and/or spatial resolution, and incomplete heart coverage. Techniques such as k-t principal component analysis (PCA) or k-t sparcity and low rank structure (SLR), which rely on the high degree of spatiotemporal correlation in first-pass perfusion data, can significantly accelerate image acquisition mitigating these problems. However, in the presence of respiratory motion, these techniques can suffer from significant degradation of image quality. A number of techniques based on non-rigid registration have been developed. However, to first approximation, breathing motion predominantly results in rigid motion of the heart. To this end, a simple robust motion correction strategy is proposed for k-t accelerated and compressed sensing (CS) perfusion imaging. A simple respiratory motion compensation (MC) strategy for k-t accelerated and compressed-sensing CMR perfusion imaging to selectively correct respiratory motion of the heart was implemented based on linear k-space phase shifts derived from rigid motion registration of a region-of-interest (ROI) encompassing the heart. A variable density Poisson disk acquisition strategy was used to minimize coherent aliasing in the presence of respiratory motion, and images were reconstructed using k-t PCA and k-t SLR with or without motion correction. The strategy was evaluated in a CMR-extended cardiac torso digital (XCAT) phantom and in prospectively acquired first-pass perfusion studies in 12 subjects undergoing clinically ordered CMR studies. Phantom studies were assessed using the Structural Similarity Index (SSIM) and Root Mean Square Error (RMSE). In patient studies, image quality was scored in a blinded fashion by two experienced cardiologists. In the phantom experiments, images reconstructed with the MC strategy had higher

  7. Infliximab treatment reduces tensile strength in intestinal anastomosis

    DEFF Research Database (Denmark)

    Jensen, Jonas Sanberg; Petersen, Nacie Bello; Biagini, Matteo

    2015-01-01

    :1) to receive either repeated IFX treatment or placebo. On day 15, three separate end-to-end anastomoses were performed on the jejunum. On postoperative day 5, tensile strength and bursting pressure for the anastomoses were tested and histologic changes examined. RESULTS: We found a significantly reduced...... as number of sutures in the tested anastomosis (coefficient = 0.51; P = 0.024). The general histologic score was significantly higher in the placebo group (5.00 +/- 1.26 versus 3.31 +/- 1.65, P = 0.03). CONCLUSIONS: Repeated high-dose IFX treatment reduces tensile strength significantly in rabbits...... effect on the healing process in intestinal anastomosis. The objective of this study was to examine the effect of repeated IFX treatment on anastomotic strength and degree of inflammation in the anastomotic line in the small intestine of rabbits. METHODS: Thirty-two rabbits were randomized (2...

  8. Effects of preoperative irradiation on primary tracheal anastomosis

    International Nuclear Information System (INIS)

    Tsubota, N.; Simpson, W.J.; Van Nostrand, A.W.P.; Pearson, F.G.

    1975-01-01

    Preoperative radiotherapy was used in the management of selected patients with cancer of the lung or trachea who might subsequently require segmental resection of bronchus or trachea and reconstruction by primary anastomosis. This study was designed to determine the effects of varying dosages of preoperative irradiation on anastomotic healing. Two rings were resected from the cervical trachea of 20 dogs following irradiation with varying doses of cesium. There were no important adverse effects on healing of the trachea or adjacent organs in dogs receiving up to 3,500 rads. All dogs receiving a higher dose than this developed some anastomotic stenosis, which was severe in 6 of 8 animals. Similar adverse effects were observed in 2 patients managed by preoperative radiotherapy (4,000 rads in three weeks) and tracheal resection with primary anastomosis

  9. Effects of preoperative irradiation on primary tracheal anastomosis

    Energy Technology Data Exchange (ETDEWEB)

    Tsubota, N.; Simpson, W.J.; Van Nostrand, A.W.P.; Pearson, F.G.

    1975-08-01

    Preoperative radiotherapy was used in the management of selected patients with cancer of the lung or trachea who might subsequently require segmental resection of bronchus or trachea and reconstruction by primary anastomosis. This study was designed to determine the effects of varying dosages of preoperative irradiation on anastomotic healing. Two rings were resected from the cervical trachea of 20 dogs following irradiation with varying doses of cesium. There were no important adverse effects on healing of the trachea or adjacent organs in dogs receiving up to 3,500 rads. All dogs receiving a higher dose than this developed some anastomotic stenosis, which was severe in 6 of 8 animals. Similar adverse effects were observed in 2 patients managed by preoperative radiotherapy (4,000 rads in three weeks) and tracheal resection with primary anastomosis.

  10. Microneural anastomosis with fibrin glue : an experimental study.

    OpenAIRE

    Suri A; Mehta V; Sarkar C

    2002-01-01

    An experimental study was designed to compare the histological analysis of nerve anastomosis with 10-0 microsurgical sutures and fibrin adhesive. Wistar albino rats′ sciatic nerves were transected and repaired either with fibrin adhesive-Beriplast P (M/s Centeon-Cadila Health Care) or with 10-0 monofilament microsutures. Histological assessment was performed at 10, 20, 30, 60 and 90 days after surgery. Functional recovery of the sciatic nerves started at two months and was near normal ...

  11. Sphincter preservation with preoperative radiation therapy and coloanal anastomosis

    Energy Technology Data Exchange (ETDEWEB)

    Minsky, Bruce D; Cohen, Alfred M; Enker, Warren E; Paty, Philip

    1995-02-01

    Purpose: To determine if preoperative radiation therapy allows sphincter preservation in the treatment of rectal cancer. Methods and Materials: Thirty patients with the diagnosis of invasive, resectable, primary adenocarcinoma of the rectum limited to the pelvis were enrolled on a Phase I/II trial of preoperative radiation therapy plus low anterior resection/coloanal anastomosis. By preoperative assessment, all patients had invasive tumors (2: T2, 28: T3) involving the distal half of the rectum and required an abdominoperineal resection. The median tumor size was 4 cm (range: 1.5-6 cm) and the median distance from the anal verge was 4 cm (range: 3-7 cm). The whole pelvis received 46.8 Gy followed by a 3.60 Gy boost to the primary tumor bed. The median follow-up was 43 months (range: 6-82 months). Results: Of the 29 patients who underwent resection, 3 (10%) had a complete pathologic response and 24 (83%) were able to successfully undergo a low anterior resection/coloanal anastomosis. The incidence of local failure was crude: 17% and 4-year actuarial: 23%. The 4-year actuarial survival was 75%. One patient developed a partial disruption of the anastomosis and two developed rectal stenosis. Analysis of sphincter function using a previously published scale was performed at the time of last follow-up in 22 of the 24 patients who underwent a low anterior resection/coloanal anastomosis. Function was good or excellent in 77%. The median number of bowel movements/day was two (range: 1-6). Conclusions: This technique may be an alternative to an abdominoperineal resection in selected patients. Continued follow-up is needed to determine if this approach ultimately has similar local control and survival rates as an abdominoperineal resection.

  12. Sphincter preservation with preoperative radiation therapy and coloanal anastomosis

    International Nuclear Information System (INIS)

    Minsky, Bruce D.; Cohen, Alfred M.; Enker, Warren E.; Paty, Philip

    1995-01-01

    Purpose: To determine if preoperative radiation therapy allows sphincter preservation in the treatment of rectal cancer. Methods and Materials: Thirty patients with the diagnosis of invasive, resectable, primary adenocarcinoma of the rectum limited to the pelvis were enrolled on a Phase I/II trial of preoperative radiation therapy plus low anterior resection/coloanal anastomosis. By preoperative assessment, all patients had invasive tumors (2: T2, 28: T3) involving the distal half of the rectum and required an abdominoperineal resection. The median tumor size was 4 cm (range: 1.5-6 cm) and the median distance from the anal verge was 4 cm (range: 3-7 cm). The whole pelvis received 46.8 Gy followed by a 3.60 Gy boost to the primary tumor bed. The median follow-up was 43 months (range: 6-82 months). Results: Of the 29 patients who underwent resection, 3 (10%) had a complete pathologic response and 24 (83%) were able to successfully undergo a low anterior resection/coloanal anastomosis. The incidence of local failure was crude: 17% and 4-year actuarial: 23%. The 4-year actuarial survival was 75%. One patient developed a partial disruption of the anastomosis and two developed rectal stenosis. Analysis of sphincter function using a previously published scale was performed at the time of last follow-up in 22 of the 24 patients who underwent a low anterior resection/coloanal anastomosis. Function was good or excellent in 77%. The median number of bowel movements/day was two (range: 1-6). Conclusions: This technique may be an alternative to an abdominoperineal resection in selected patients. Continued follow-up is needed to determine if this approach ultimately has similar local control and survival rates as an abdominoperineal resection

  13. Effect of omentum graft on esophageal anastomosis in dogs

    OpenAIRE

    A. K. Mahdi

    2011-01-01

    The aim of this study was to evaluate the complications and final function outcome of wrapping nonvascularized omentum graft around the suture line of esophageal anastomosis. Twelve adult local breed dogs were used in this study. The animals were divided into two equal groups (control and treated), all animal induced into general anesthesia by injection of atropen sulphate in a dose 0.04 mg/kg B.W, intramuscularly then after 15 minute given mixture of ketamine hydrochloride and xylazine hydro...

  14. The Efficacy of Polydioxanone Monofilament Absorbable Suture for Tracheal Anastomosis

    OpenAIRE

    Kawahara, Katsunobu; Yamasaki, Naoya; Yamamoto, Satoshi; Nagayasu, Takeshi; Kusano, Hiroyuki; Akamine, Shinji; Takahashi, Takao; Tomita, Masao

    1994-01-01

    To evaluate the efficacy of polydioxanon absorbable suture for tracheal anastomoses, we performed an experimental study using dose. Eight adult mongrel dogs underwent sleeve resection of the mediastinal trachea. A length of ten to twelve cartilage rings was resected. An end-to-end anastomosis was performed using either interrupted or continuous running 4-0 polydioxanone (PDS) suture. There was no detectable difference bronchoscopically, microangiografically, or histologically, in tracheal ana...

  15. Ethyl pyruvate protects colonic anastomosis from ischemia-reperfusion injury.

    Science.gov (United States)

    Unal, B; Karabeyoglu, M; Huner, T; Canbay, E; Eroglu, A; Yildirim, O; Dolapci, M; Bilgihan, A; Cengiz, O

    2009-03-01

    Ethyl pyruvate is a simple derivative in Ca(+2)- and K(+)-containing balanced salt solution of pyruvate to avoid the problems associated with the instability of pyruvate in solution. It has been shown to ameliorate the effects of ischemia-reperfusion (I/R) injury in many organs. It has also been shown that I/R injury delays the healing of colonic anastomosis. In this study, the effect of ethyl pyruvate on the healing of colon anastomosis and anastomotic strength after I/R injury was investigated. Anastomosis of the colon was performed in 32 adult male Wistar albino rats divided into 4 groups of 8 individuals: (1) sham-operated control group (group 1); (2) 30 minutes of intestinal I/R by superior mesenteric artery occlusion (group 2); (3) I/R+ ethyl pyruvate (group 3), ethyl pyruvate was administered as a 50-mg/kg/d single dose; and (4) I/R+ ethyl pyruvate (group 4), ethyl pyruvate administration was repeatedly (every 6 hours) at the same dose (50 mg/kg). On the fifth postoperative day, animals were killed. Perianastomotic tissue hydroxyproline contents and anastomotic bursting pressures were measured in all groups. When the anastomotic bursting pressures and tissue hydroxyproline contents were compared, it was found that they were decreased in group 2 when compared with groups 1, 3, and 4 (P .05). Ethyl pyruvate significantly prevents the delaying effect of I/R injury on anastomotic strength and healing independent from doses of administration.

  16. Intraoperative colonic lavage and primary anastomosis in peritonitis and obstruction.

    Science.gov (United States)

    Biondo, S; Jaurrieta, E; Jorba, R; Moreno, P; Farran, L; Borobia, F; Bettonica, C; Poves, I; Ramos, E; Alcobendas, F

    1997-02-01

    The surgical management of left colonic emergencies has evolved in the past few decades. Recently, there has been increasing interest in resection with primary anastomosis in selected cases. The aim of this study was to evaluate the differences in outcome in patients with peritonitis or obstruction treated by resection, on-table lavage and primary anastomosis of the left colon. Between January 1992 and August 1995, 212 patients underwent emergency operation for a distal colonic lesion: 97 presented with peritonitis, 113 with obstruction and two with other indications. Intraoperative colonic lavage was performed in 37 patients with obstruction and in 24 with an acute intra-abdominal inflammatory process. The postoperative mortality rate was 5 per cent. The incidence of clinical anastomotic leakage was 5 per cent. Wound infection was observed in ten patients (16 per cent), more often in those with peritonitis (P = 0.03). The overall mean(s.d.) hospital stay was 15(9) days. Resection, on-table lavage and primary anastomosis constitute the operation of choice for selected patients with left colonic emergency.

  17. Trichobezoar obstruction after stapled jejunal anastomosis in a dog.

    Science.gov (United States)

    Carobbi, Barbara; Foale, Robert D; White, Richard A S

    2009-04-01

    To describe an unusual long-term complication of circular end-to-end anastomosis (CEEA) stapling in a dog. Clinical case report. An 11-year-old, female neutered, Labrador Retriever. The dog was referred for clinical signs of bowel obstruction. An enterectomy was performed 2 years before presentation using a CEEA stapling device. Palpation, plain radiographs, and ultrasound of the abdomen confirmed the presence of a mass in the bowel, causing obstruction, and requiring surgical approach. An exploratory celiotomy revealed a 5 cm mass in the jejunum, involving the site of the previous surgery. The mass was removed by enterectomy. Dissection of the mass revealed the presence of many staples at the previous enterectomy site, and a trichobezoar entangled in the exposed parts of the staples. An enterectomy was required to treat an intestinal obstruction caused by a trichobezoar entangled in a CEEA-stapled anastomosis. Development of trichobezoar and subsequent bowel obstruction should be considered an unusual but potential long-term complication of CEEA-stapled anastomosis.

  18. Rectovaginal fistula following colectomy with an end-to-end anastomosis stapler for a colorectal adenocarcinoma.

    Science.gov (United States)

    Klein, A; Scotti, S; Hidalgo, A; Viateau, V; Fayolle, P; Moissonnier, P

    2006-12-01

    An 11-year-old, female neutered Labrador retriever was presented with a micro-invasive differentiated papillar adenocarcinoma at the colorectal junction. A colorectal end-to-end anastomosis stapler device was used to perform resection and anastomosis using a transanal technique. A rectovaginal fistula was diagnosed two days later. An exploratory laparotomy was conducted and the fistula was identified and closed. Early dehiscence of the colon was also suspected and another colorectal anastomosis was performed using a manual technique. Comparison to a conventional manual technique of intestinal surgery showed that the use of an automatic staple device was quicker and easier. To the authors' knowledge, this is the first report of a rectovaginal fistula occurring after end-to-end anastomosis stapler colorectal resection-anastomosis in the dog. To minimise the risk of this potential complication associated with the limited surgical visibility, adequate tissue retraction and inspection of the anastomosis site are essential.

  19. Reanastomosis with Stapler in Duodenojejunal Junction Anastomosis Leakage: A Case Report

    Directory of Open Access Journals (Sweden)

    Ahmet Seker

    2013-04-01

    Full Text Available After anastomosis leakages, treatment of patient gets more difficult and mortality rates increase. At lower level gastrointestinal anastomosis leakages, because of always there is an ostomy alternative, digestion problems are seen lesser. But at upper level gastrointestinal system anastomosis leakages, when it is taken account of nutrient condition of patient, requirement of making anastomos increases. So moratlity rates increase. At this article we aimed to present a different technique that we administered on management of a patient who had duodenojejunal junction anastomosis leakage.

  20. Double 90 Degrees Counterrotated End-to-End-Anastomosis: An Experimental Study of an Intestinal Anastomosis Technique.

    Science.gov (United States)

    Holzner, Philipp; Kulemann, Birte; Seifert, Gabriel; Glatz, Torben; Chikhladze, Sophia; Höppner, Jens; Hopt, Ulrich; Timme, Sylvia; Bronsert, Peter; Sick, Olivia; Zhou, Cheng; Marjanovic, Goran

    2015-06-01

    The aim of the article is to investigate a new anastomotic technique compared with standardized intestinal anastomotic procedures. A total of 32 male Wistar rats were randomized to three groups. In the Experimental Group (n = 10), the new double 90 degrees inversely rotated anastomosis was used, in the End Group (n = 10) a single-layer end-to-end anastomosis, and in the Side Group (n = 12) a single-layer side-to-side anastomosis. All anastomoses were done using interrupted sutures. On postoperative day 4, rats were relaparotomized. Bursting pressure, hydroxyproline concentration, a semiquantitative adhesion score and two histological anastomotic healing scores (mucosal healing according to Chiu and overall anastomotic healing according to Verhofstad) were collected. Most data are presented as median (range). p < 0.05 was considered significant. Anastomotic insufficiency occurred only in one rat of the Side Group. Median bursting pressure in the Experimental Group was 105 mm Hg (range = 72-161 mm Hg), significantly higher in the End Group (164 mm Hg; range = 99-210 mm Hg; p = 0.021) and lower in the Side Group by trend (81 mm Hg; range = 59-122 mm Hg; p = 0.093). Hydroxyproline concentration did not differ significantly in between the groups. The adhesion score was 2.5 (range = 1-3) in the Experimental Group, 2 (range = 1-2) in the End Group, but there were significantly more adhesions in the Side Group (range = 3-4); p = 0.020 versus Experimental Group, p < 0.001 versus End Group. The Chiu Score showed the worst mucosal healing in the Experimental Group. The overall Verhofstad Score was significantly worse (mean = 2.032; standard deviation [SD] = 0.842) p = 0.031 and p = 0.002 in the Experimental Group, compared with the Side Group (mean = 1.729; SD = 0.682) and the End Group (mean = 1.571; SD = 0.612). The new anastomotic technique is feasible and did not show any relevant complication. Even though it was superior to the side-to-side anastomosis by trend with

  1. Wellhead compression

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Joe [Sertco Industries, Inc., Okemah, OK (United States); Vazquez, Daniel [Hoerbiger Service Latin America Inc., Deerfield Beach, FL (United States); Jacobs, Denis Richard [Hoerbiger do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Over time, all wells experience a natural decline in oil and gas production. In gas wells, the major problems are liquid loading and low downhole differential pressures which negatively impact total gas production. As a form of artificial lift, wellhead compressors help reduce the tubing pressure resulting in gas velocities above the critical velocity needed to surface water, oil and condensate regaining lost production and increasing recoverable reserves. Best results come from reservoirs with high porosity, high permeability, high initial flow rates, low decline rates and high total cumulative production. In oil wells, excessive annulus gas pressure tends to inhibit both oil and gas production. Wellhead compression packages can provide a cost effective solution to these problems by reducing the system pressure in the tubing or annulus, allowing for an immediate increase in production rates. Wells furthest from the gathering compressor typically benefit the most from wellhead compression due to system pressure drops. Downstream compressors also benefit from higher suction pressures reducing overall compression horsepower requirements. Special care must be taken in selecting the best equipment for these applications. The successful implementation of wellhead compression from an economical standpoint hinges on the testing, installation and operation of the equipment. Key challenges and suggested equipment features designed to combat those challenges and successful case histories throughout Latin America are discussed below.(author)

  2. Magnets

    International Nuclear Information System (INIS)

    Young, I.R.

    1984-01-01

    A magnet pole piece for an NMR imaging magnet is made of a plurality of magnetic wires with one end of each wire held in a non-magnetic spacer, the other ends of the wires being brought to a pinch, and connected to a magnetic core. The wires may be embedded in a synthetic resin and the magnetisation and uniformity thereof can be varied by adjusting the density of the wires at the spacer which forms the pole piece. (author)

  3. Single Layered Versus Double Layered Intestinal Anastomosis: A Randomized Controlled Trial

    Science.gov (United States)

    Mohapatra, Vandana; Singh, Surendra; Rath, Pratap Kumar; Behera, Tapas Ranjan

    2017-01-01

    Introduction Gastrointestinal anastomosis is one of the most common procedures being performed in oesophagogastric, hepatobiliary, bariatric, small bowel and colorectal surgery; however, the safety and efficacy of single layer or double layer anastomotic technique is still unclear. Aim To assess and compare the efficacy, safety and cost effectiveness of single layered versus double layered intestinal anastomosis. Materials and Methods This prospective, double-blind, randomized controlled comparative study comprised of patients who underwent intestinal resection and anastomosis. They were randomly assigned to undergo either single layered extra-mucosal anastomosis (Group-A) or double layered intestinal anastomosis (Group-B). Primary outcome measures included average time taken for anastomosis, postoperative complications, mean duration of hospital stay and cost of suture material used; secondary outcome measures assessed the postoperative return of bowel function. Statistical analysis was done by Chi-square test and student t-test. Results A total of 97 participants were randomized. Fifty patients were allocated to single layered extramucosal continuous anastomosis (Group-A) and 47 patients to double layered anastomosis (Group-B). The patients in each group were well matched for age, sex and diagnosis. The mean time taken for anastomosis (15.12±2.27 minutes in Group-A versus 24.38±2.26 minutes in Group-B) and the length of hospital stay (5.90±1.43 days in Group-A versus 7.29±1.89 days in Group-B) was significantly shorter in Group-A {p-value anastomosis. However, there was no significant difference in the complication rates between the two groups. Conclusion It can be concluded that single layered extramucosal continuous intestinal anastomosis is equally safe and perhaps more cost effective than the conventional double layered method and may represent the optimal choice for routine surgical practice. PMID:28764239

  4. Transfer of Learning from Practicing Microvascular Anastomosis on Silastic Tubes to Rat Abdominal Aorta.

    Science.gov (United States)

    Mokhtari, Pooneh; Tayebi Meybodi, Ali; Lawton, Michael T; Payman, Andre; Benet, Arnau

    2017-12-01

    Learning to perform microvascular anastomosis is difficult. Laboratory practice models using artificial vessels are frequently used for this purpose. However, the efficacy of such practice models has not been objectively assessed for the performance of microvascular anastomosis during live surgical settings. This study was conducted to assess the transfer of learning from practicing microvascular anastomosis on tubes to anastomosing rat abdominal aorta. Ten surgeons without any experience in microvascular anastomosis were randomly assigned to an experimental or a control group. Both groups received didactic and visual training on end-to-end microvascular anastomosis. The experimental group received 24 sessions of hands-on training on microanastomosis using Silastic tubes. Next, both groups underwent recall tests on weeks 1, 2, and 8 after training. The recall test consisted of completing an end-to-end anastomosis on the rat's abdominal aorta. Anastomosis score, the time to complete the anastomosis, and the average time to place 1 stitch on the vessel perimeter were compared between the 2 groups. Compared with the control group, the experimental group did significantly better in terms of anastomosis score, total time, and per-stitch time. The measured variables showed stability and did not change significantly between the 3 recall tests. The skill of microvascular anastomosis is transferred from practicing on Silastic tubes to rat's abdominal aorta. Considering the relative advantages of Silastic tubes to live rodent surgeries, such as lower cost and absence of ethical issues, our results support the widespread use of Silastic tubes in training programs for microvascular anastomosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Comparative study of three methods of esophageal anastomosis in dogs

    Directory of Open Access Journals (Sweden)

    Z. T. Abd Al-Maseeh

    2009-01-01

    Full Text Available This study was performed to compare three methods of esophageal anastomosis. Twenty four healthy adult dogs were used in this study. The animals were divided into three groups; each one consisted of 8 animals. In group 1; two layers were used to perform the esophageal anastomosis. The first layer represented simple interrupted suture to close the mucosa with knot inside the lumen, and the second layer represented horizontal mattress interrupted suture to close the other layers of esophagus. While in group 2; one layer of cross interrupted mattress suture was used to close all layers of esophageal wall, and in group 3; one layer of Schmieden's suture was used to close all layers of esophageal wall. The results of clinical, radiological and histopathological studies after 15 and 30 days of surgical operation revealed that most of the animals showed different degrees of difficulty concerning the moderate dysphagia and regurgitation. The radiological study showed significant difference of stenosis. The best results were recorded in the second group where the mean degree of stenosis was 7.69%, however the mean degree of stenosis was 42.80% in the first group, while the mean degree of stenosis in the third groups was 37.81%, through 30 days. The histopathological study of group 2 showed rapid healing of the site of anastomosis, lack of granulation tissue and consequently the less degree of stricture and other complications as compared with groups 1 and 3. The Schmieden's suture was characterized by its standard short time as compared with group 1 and 2, although accompanied by some complications. In conclusion this study revealed that the cross mattress suture used in the second group characterized by faster healing and minimal amount of fibrous tissue formation manifested by decrease in moderate degree of stenosis as compared with the two other suture patterns used in the first and third groups.

  6. Arbuscular mycorrhizal fungi reveal distinct patterns of anastomosis formation and hyphal healing mechanisms between different phylogenic groups

    NARCIS (Netherlands)

    De Souza, F.A.; Fernández, F.; Delmas, N.S.; Declerck, S.

    2005-01-01

    The significance of anastomosis formation and the hyphal healing mechanism (HHM) for functionality and integrity of the arbuscular mycorrhizal (AM) fungal mycelial network remains poorly documented. Four Glomeraceae and three Gigasporaceae were cultured monoxenically. Anastomosis formation was

  7. Speech Compression

    Directory of Open Access Journals (Sweden)

    Jerry D. Gibson

    2016-06-01

    Full Text Available Speech compression is a key technology underlying digital cellular communications, VoIP, voicemail, and voice response systems. We trace the evolution of speech coding based on the linear prediction model, highlight the key milestones in speech coding, and outline the structures of the most important speech coding standards. Current challenges, future research directions, fundamental limits on performance, and the critical open problem of speech coding for emergency first responders are all discussed.

  8. Pancreatico-Gastric Anastomosis with and without Sutures – Experimental Swine Model

    Directory of Open Access Journals (Sweden)

    Tudor A

    2015-06-01

    Full Text Available Objectives. The aim of our study is to identify a surgical technical that has the lowest rate of pancreatic fistulas in pancreatico-gastric anastomosis following duodenopancreatectomies. We studied pancreatico-gastric anastomosis performed with stitches compared to the ones performed without stitches.

  9. Mediastinoscopic Bilateral Bronchial Release for Long Segmental Resection and Anastomosis of the Trachea

    OpenAIRE

    Kang, Jeong-Han; Park, In Kyu; Bae, Mi-Kyung; Hwang, Yoohwa

    2011-01-01

    The extent of resection and release of the trachea is important for successful anastomosis. Bilateral bronchial dissection is one of the release techniques for resection of the lower trachea. We present the experience of cervical video-assisted mediastinoscopic bilateral bronchial release for long segmental resection and anastomosis of the lower trachea.

  10. Intrathoracic versus cervical anastomosis and predictors of anastomotic leakage after oesophagectomy for cancer

    NARCIS (Netherlands)

    Gooszen, J. A. H.; Goense, L.; Gisbertz, S. S.; Ruurda, J. P.; van Hillegersberg, R.; van Berge Henegouwen, M. I.

    2018-01-01

    Studies comparing the anastomotic leak rate in patients with an intrathoracic versus a cervical anastomosis after oesophagectomy are equivocal. The aim of this study was to compare clinical outcome after oesophagectomy in patients with an intrathoracic or cervical anastomosis, and to identify

  11. Difference in Recurrence Patterns Between Anastomosis and Strictureplasty After Surgical Treatment for Crohn Disease

    Science.gov (United States)

    Hayakawa, Shoichiro; Hotokezaka, Masayuki; Ikeda, Takuto; Uchiyama, Shuichiro; Chijiiwa, Kazuo

    2012-01-01

    This study aimed to investigate whether the initial indication for surgery or type of surgery (strictureplasty or resection) performed determines recurrence patterns in patients with Crohn disease. Recurrence patterns of 41 patients (31 patients: only resection and anastomosis of the intestine, and 10 patients: strictureplasty with/without resection and anastomosis) who underwent operation for recurrent Crohn disease (June 2002–December 2010) were evaluated. Strictureplasty for nonperforating disease was performed at 17 sites, and reoperation was required at 11 sites (10 sites for nonperforating disease and 1 site for perforating disease). There was a significant difference in the recurrence pattern in patients who underwent resection and anastomosis (P resection and anastomosis (P resection and anastomosis was performed for nonperforating and for perforating disease. Initial indication for surgery, but not the type of surgery, appeared to determine recurrence patterns. PMID:23102077

  12. Establishment of an immunocompetent nipple valve anastomosis to prevent faecal reflux after ileocolic resection in dogs.

    Science.gov (United States)

    Ecker, K W; Pistorius, G; Menger, M D; Feifel, G

    2000-05-01

    To construct an immunocompetent nipple valve anastomosis (NVA) to exclude faecal reflux and compare it with an end-to-end anastomosis to see if it would prevent recurrent inflammation caused by intraluminal bacterial antigens in Crohn's disease. Laboratory study. Teaching hospital, Germany. Two groups of six beagle dogs each of which had NVA or end-to-end anastomosis. Construction of a NVA by stapling the telescoped nipple, and replacing the ileal mucosa on the valve by colonic mucosa; end-to-end anastomosis. Radiological, bacteriological, angiographic, and morphometric results. Absolute retrograde pressure-competence and free orthograde permeability of the NVA resulted in significantly lower intestinal bacterial counts compared with the end-to-end anastomosis (p < 0.05). Transposition of colonic mucosa was successful as demonstrated by revascularisation from the ileal nipple and looked normal on morphometry. If NVA were constructed in patients with Crohn's disease, recurrences should be prevented, which would verify the immunopathogenetic hypothesis of new inflammation.

  13. Microvascular stent anastomosis using N-fibroin stents: feasibility, ischemia time, and complications.

    Science.gov (United States)

    Smeets, Ralf; Vorwig, Oliver; Wöltje, Michael; Gaudin, Robert; Luebke, Andreas M; Beck-Broichsitter, Benedicta; Rheinnecker, Michael; Heiland, Max; Grupp, Katharina; Gröbe, Alexander; Hanken, Henning

    2016-05-01

    To evaluate a novel microvascular anastomosis technique using N-fibroin stents. Cylinder stents of 1 mm diameter and 5 mm length were fabricated using N-fibroin from silkworms. In 22 rats, aortas were dissected, and the stent was inserted into the two ends of the aorta and fixed using methylmethacrylate. Stent anastomosis was successful in 21 (96%) rats. The mean ischemia time was 7.4 minutes, significantly shorter than the 15.9 minutes in the control group with conventional sutures (P stent anastomosis cases, and marked host rejection was evident at the stent anastomosis sites. Around the stents, thrombi were frequent (52%). Our study demonstrated the basic feasibility of stent anastomosis using N-fibroin stents and reduced ischemia time. However, thrombus formation, frequent and severe abdominal infections, and heavy host rejection remain critical issues. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Management of post-gastrectomy anastomosis site obstruction with a self-expandable metallic stent.

    Science.gov (United States)

    Cha, Ra Ri; Lee, Sang Soo; Kim, Hyunjin; Kim, Hong Jun; Kim, Tae-Hyo; Jung, Woon Tae; Lee, Ok Jae; Bae, Kyung Soo; Jeong, Sang-Ho; Ha, Chang Yoon

    2015-04-28

    Post-gastrectomy anastomosis site obstruction is a relatively rare complication after a subtotal gastrectomy. We present a case of a 75-year-old man who underwent a truncal vagotomy, omental patch, gastrojejunostomy, and Braun anastomosis for duodenal ulcer perforation and a gastric outlet obstruction. Following the 10(th) postoperative day, the patient complained of abdominal discomfort and vomiting. We diagnosed post-gastrectomy anastomosis site obstruction by an upper gastrointestinal series and an upper endoscopic examination. We inserted a self-expandable metallic stent (SEMS) at the anastomosis site. The stent was fully expanded after deployment. On the day following the stent insertion, the patient began to eat, and his abdominal discomfort was resolved. This paper describes the successful management of post-gastrectomy anastomosis site obstruction with temporary placement of a SEMS.

  15. A Comfortable Solution To Tracheal Anastomosis Protection: Tracheal Retention Sutures.

    Science.gov (United States)

    Karapolat, Sami; Turkyilmaz, Atila; Seyis, Kubra Nur; Tekinbas, Celal

    2018-04-01

    Fixation of the chin to the anterior chest wall is the most commonly used method of reducing anastomotic tension following a segmental resection of the trachea and reconstruction with primary anastomosis. However, the sutures required for this method may lead to various organic and psychological problems. In five patients who underwent tracheal resection and primary anastomosis, retention sutures were placed on the proximal and distal-lateral edges of the anastomotic line rather than placing a Guardian chin stitch. All patients were mobilised in the early postoperative period and were able to perform their routine daily activities without restrictions. During their average 14.4 months of follow-up, no complications were found in their anastomotic lines during their clinical, radiological, and bronchoscopic assessments. The placement of tracheal retention sutures proved an inexpensive and reliable method to reduce anastomotic tension without additional surgical burden, and was effective in terms of patient comfort. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  16. Compatibility and incompatibility in hyphal anastomosis of arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Candido Barreto de Novais

    Full Text Available ABSTRACT: Arbuscular mycorrhizal fungi (AMF, which live in symbiosis with 80 % of plants, are not able to grow when separated from their hosts. Spore germination is not host-regulated and germling growth is shortly arrested in the absence of host roots. Germling survival chances may be increased by hyphal fusions (anastomoses, which allow access to nutrients flowing in the extraradical mycelium (ERM. Perfect anastomoses, occurring with high frequency among germlings and the ERM of the same isolate, show protoplasm continuity and disappearance of hyphal walls. A low frequency of perfect fusions has been detected among co-specific genetically different isolates, although fungal nuclei have been consistently detected in all perfect fusions, suggesting active nuclear migration. When plants of different taxa establish symbioses with the same AMF species, anastomoses between ERM spreading from single root systems establish a common mycelium, which is an essential element to plant nutrition and communication. The interaction among mycelia produced by different isolates may also lead to pre-fusion incompatibility which hinders anastomosis formation, or to incompatibility after fusion, which separates the hyphal compartments. Results reported here, obtained by analyses of hyphal compatibility/incompatibility in AMF, suggest that anastomosis formation and establishment of protoplasm flow, fundamental to the maintenance of mycelial physiological and genetic continuity, may affect the fitness of these ecologically important biotrophic fungi.

  17. Experimental research on end-to-side anastomosis of peripheral nerves and effect of FK506 on end-to-side anastomosis.

    Science.gov (United States)

    Yang, L M; Wu, Y X; Zhang, X P; Li, X H

    2014-01-01

    To study the effects of end-to-side anastomosis of initially-denatured nerves at different times. 60 male Wistar albino rats were used to fabricate animal models for the experiment on end-to-side anastomosis of peripheral nerves and 50 female Wistar albino rats were used to fabricate animal models for the experiment on the effect of FK506 on end-to-side anastomosis. Bilateral common peroneal nerve, tibialis anterior muscle electrophysiological and histological examinations, tibialis anterior muscle wet muscle weight determination, and motor end plate examination were performed 3 months after operation. All recovery rates of action potential, single muscle contraction force and tetanic contraction force of the FK506 experimental group are significantly higher than those of the control group and the sectional area of muscle fiber is also higher than that of the control group of normal saline. The best time for end-to-side anastomosis of nerves should be controlled within 2 weeks and the effect of end-to-side anastomosis of nerves will gradually become unsatisfactory. FK506 plays a role in promoting functional rehabilitation following nerve end-to-side anastomosis (Tab. 7, Fig. 4, Ref. 31).

  18. Systematic review and meta-analysis of published, randomized, controlled trials comparing suture anastomosis to stapled anastomosis for ileostomy closure.

    Science.gov (United States)

    Sajid, M S; Craciunas, L; Baig, M K; Sains, P

    2013-12-01

    The objective of this article is to systematically analyze the randomized, controlled trials comparing the effectiveness of suture anastomosis (SUA) versus stapled anastomosis (STA) in patients undergoing ileostomy closure. Randomized, controlled trials comparing the effectiveness of SUA versus STA in patients undergoing ileostomy closure were analyzed using RevMan(®), and combined outcomes were expressed as odds risk ratio (OR) and standardized mean difference (SMD). Four randomized, controlled trials that recruited 645 patients were retrieved from electronic databases. There were 327 patients in the STA group and 318 patients in the SUA group. There was significant heterogeneity among included trials. Operative time (SMD -1.02; 95 % CI -1.89, -0.15; z = 2.29; p infection, reoperation and readmission were similar following STA and SUA in patients undergoing ileostomy closure. Length of hospital stay was also similar between STA and SUA groups. In ileostomy closure, STA was associated with shorter operative time and lower risk of postoperative small bowel obstruction. However, STA and SUA were similar in terms of anastomotic leak, surgical site infection, readmission, reoperations and length of hospital stay.

  19. Compressed sensing real-time cine cardiovascular magnetic resonance: accurate assessment of left ventricular function in a single-breath-hold.

    Science.gov (United States)

    Kido, Tomoyuki; Kido, Teruhito; Nakamura, Masashi; Watanabe, Kouki; Schmidt, Michaela; Forman, Christoph; Mochizuki, Teruhito

    2016-08-24

    Cardiovascular cine magnetic resonance (CMR) accelerated by compressed sensing (CS) is used to assess left ventricular (LV) function. However, it is difficult for prospective CS cine CMR to capture the complete end-diastolic phase, which can lead to underestimation of the end-diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF), compared to retrospective standard cine CMR. This prospective study aimed to evaluate the diagnostic quality and accuracy of single-breath-hold full cardiac cycle CS cine CMR, acquired over two heart beats, to quantify LV volume in comparison to multi-breath-hold standard cine CMR. Eighty-one participants underwent standard segmented breath-hold cine and CS real-time cine CMR examinations to obtain a stack of eight contiguous short-axis images with same high spatial (1.7 × 1.7 mm(2)) and temporal resolution (41 ms). Two radiologists independently performed qualitative analysis of image quality (score, 1 [i.e., "nondiagnostic"] to 5 [i.e., "excellent"]) and quantitative analysis of the LV volume measurements. The total examination time was 113 ± 7 s for standard cine CMR and 24 ± 4 s for CS cine CMR (p cine image quality was slightly lower than standard cine (4.8 ± 0.5 for standard vs. 4.4 ± 0.5 for CS; p cine were above 4 (i.e., good). No significant differences existed between standard and CS cine MR for all quantitative LV measurements. The mean differences with 95 % confidence interval (CI), based on Bland-Altman analysis, were 1.3 mL (95 % CI, -14.6 - 17.2) for LV end-diastolic volume, 0.2 mL (95 % CI, -9.8 to10.3) for LV end-systolic volume, 1.1 mL (95 % CI, -10.5 to 12.7) for LV stroke volume, 1.0 g (95 % CI, -11.2 to 13.3) for LV mass, and 0.4 % (95 % CI, -4.8 - 5.6) for LV ejection fraction. The interobserver and intraobserver variability for CS cine MR ranged from -4.8 - 1.6 % and from -7.3 - 9.3 %, respectively, with slopes of the regressions ranging 0.88-1.0 and 0

  20. The Complete Genome of a New Betabaculovirus from Clostera anastomosis.

    Directory of Open Access Journals (Sweden)

    Feifei Yin

    Full Text Available Clostera anastomosis (Lepidoptera: Notodontidae is a defoliating forest insect pest. Clostera anastomosis granulovirus-B (ClasGV-B belonging to the genus Betabaculovirus of family Baculoviridae has been used for biological control of the pest. Here we reported the full genome sequence of ClasGV-B and compared it to other previously sequenced baculoviruses. The circular double-stranded DNA genome is 107,439 bp in length, with a G+C content of 37.8% and contains 123 open reading frames (ORFs representing 93% of the genome. ClasGV-B contains 37 baculovirus core genes, 25 lepidopteran baculovirus specific genes, 19 betabaculovirus specific genes, 39 other genes with homologues to baculoviruses and 3 ORFs unique to ClasGV-B. Hrs appear to be absent from the ClasGV-B genome, however, two non-hr repeats were found. Phylogenetic tree based on 37 core genes from 73 baculovirus genomes placed ClasGV-B in the clade b of betabaculoviruses and was most closely related to Erinnyis ello GV (ErelGV. The gene arrangement of ClasGV-B also shared the strongest collinearity with ErelGV but differed from Clostera anachoreta GV (ClanGV, Clostera anastomosis GV-A (ClasGV-A, previously also called CaLGV and Epinotia aporema GV (EpapGV with a 20 kb inversion. ClasGV-B genome contains three copies of polyhedron envelope protein gene (pep and phylogenetic tree divides the PEPs of betabaculoviruses into three major clades: PEP-1, PEP-2 and PEP/P10. ClasGV-B also contains three homologues of P10 which all harbor an N-terminal coiled-coil domain and a C-terminal basic sequence. ClasGV-B encodes three fibroblast growth factor (FGF homologues which are conserved in all sequenced betabaculoviruses. Phylogenetic analysis placed these three FGFs into different groups and suggested that the FGFs were evolved at the early stage of the betabaculovirus expansion. ClasGV-B is different from previously reported ClasGV-A and ClanGV isolated from Notodontidae in sequence and gene

  1. The Effects of Hyperbaric Oxygen Therapy on Experimental Colon Anastomosis After Preoperative Chemoradiotherapy

    Science.gov (United States)

    Yildiz, Ramazan; Can, Mehmet Fatih; Yagci, Gokhan; Ozgurtas, Taner; Guden, Metin; Gamsizkan, Mehmet; Ozturk, Erkan; Cetiner, Sadettin

    2013-01-01

    The aim of the present study was to investigate the effect of hyperbaric oxygen therapy (HBOT) on colon anastomosis after chemoradiotherapy (CRT). Sixty female Wistar-Albino rats were divided into 5 groups and underwent left colon resection and end-to-end anastomosis. CRT simulation was performed on 2 sham groups before the anastomosis, and 1 of these groups was administered additional postoperative HBOT. Two groups were administered CRT before the anastomosis, and 1 of them received additional postoperative HBOT. On postoperative day 5, all groups underwent relaparotomy; burst pressure was measured and samples were obtained for histopathologic and biochemical analysis. There was a significant weight loss in the CRT groups and postoperative HBOT had an improving effect. Significantly decreased burst pressure values increased up to the levels of the controls after HBOT. Hydroxyproline levels were elevated in all groups compared to the control group. Hydroxyproline levels decreased with HBOT after CRT. No significant difference was observed between the groups regarding fibrosis formation at the anastomosis site. However, regression was observed in fibrosis in the group receiving HBOT after CRT. Preoperative CRT affected anastomosis and wound healing unfavorably. These unfavorable effects were alleviated by postoperative HBOT. HBOT improved the mechanical and biochemical parameters of colon anastomosis in rats. PMID:23438274

  2. Laparoscopic intersphincteric resection for low rectal cancer: comparison of stapled and manual coloanal anastomosis.

    Science.gov (United States)

    Cong, J C; Chen, C S; Ma, M X; Xia, Z X; Liu, D S; Zhang, F Y

    2014-05-01

    The study aim was to analyse the safety and feasibility of laparoscopic intersphincteric resection with stapled coloanal anastomosis for low rectal cancer. Between March 2009 and August 2010, 22 patients underwent laparoscopic intersphincteric resection with a stapled coloanal anastomosis without a diverting ileostomy. The results were compared retrospectively with hand-sewn coloanal anastomoses performed between January 2001 and May 2009, which included 55 open and 38 laparoscopic intersphincteric resections. The morbidity comparison only included data relevant to the anastomosis. Function was compared using the Saito function questionnaire and the Wexner score and only involved data relevant to the laparoscopy. The anastomotic complication rates were similar for fistula, bleeding and neorectal mucosal prolapse (P = 0.526, P = 0.653 and P = 0.411, respectively). Anastomotic leakage and stricture formation of the stapled coloanal anastomosis were significantly lower than those of the hand-sewn coloanal anastomosis (P = 0.037 and P = 0.028, respectively). There were no significant differences in the Saito function questionnaire and the Wexner score between the stapled and hand-sewn coloanal anastomotic groups (all P > 0.05). Laparoscopic intersphincteric resection with a stapled coloanal anastomosis is technically feasible and is less likely to result in anastomotic leakage and stricture formation than a hand-sewn anastomosis. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

  3. Description and evaluation of a bench porcine model for teaching surgical residents vascular anastomosis skills

    Directory of Open Access Journals (Sweden)

    Jauch Karl-Walter

    2010-07-01

    Full Text Available Abstract Background Numerous models, of variable quality, exist to impart the complex skills required to perform vascular anastomosis. These models differ with regard to the kinds of materials used, as well as their sizes, the time needed for their preparation, their availability, and the associated costs. The present study describes a bench model that uses formalin-fixed porcine aorta, and its evaluation by young surgical residents during a recent skills course. Findings The aortic segments used were a by-product of slaughtering. They were fixed and stored after harvesting for eventual use. Ten young surgical residents participated, and each performed one end-to-side vascular anastomosis. The evaluation was a questionnaire maintaining anonymity of the participant containing questions addressing particular aspects of the model and the experiences of the trainee, along with their ratings concerning the need for a training course to learn vascular anastomosis techniques. The scoring on the survey was done using a global 6-point rating scale (Likert Scale. In addition, we ranked the present model by reviewing the current literature for models that address vascular anastomosis skills. The trainees who participated were within their first two years of training (1.25 ± 0.46. A strong agreement in terms of the necessity of training for vascular anastomosis techniques was evident among the participating trainees (5.90 ± 0.32, who had only few prior manual experiences (total number 1.50 ± 0.53. The query revealed a strong agreement that porcine aorta is a suitable model that fits the needs for training vascular anastomosis skills (5.70 ± 0.48. Only a few bench models designed to teach surgical residents vascular anastomosis techniques were available in the literature. Conclusions The preparatory and financial resources needed to perform anastomosis skills training using porcine aorta are few. The presented bench model appears to be appropriate for

  4. Delayed Coloanal Anastomosis for rectovaginal fistula after colorectal resection for deep endometriosis.

    Science.gov (United States)

    Gallo, Gaetano; Luc, Alberto Realis; Tutino, Roberta; Clerico, Giuseppe; Trompetto, Mario

    2016-11-28

    The deep infiltrating endometriosis, defined as a subperitoneal infiltration of endometrial implants of ≥ 5 mm involving not only the colorectal tract but also rectovaginal septum, vagina and bladder often requires a challenging surgery. Endometriosis nodes of the rectovaginal septum, if symptomatic, need a resection of the involved colorectal tract with colorectal or coloanal anastomosis. Unfortunately in these cases is not uncommon the possibility of a postoperative rectovaginal fistula (RVF), caused by the weakness of the septum that must be skeletonized to completely remove the endometriosis nodes. Here we present a case of anastomotic leakage with high RVF after colorectal resection and low colorectal anastomosis for deep endometriosis in which, for a chronic pelvic sepsis and a high risk of failure of a new immediate coloanal anastomosis, a Turnbull-Cutait pull-through with delayed coloanal anastomosis (DCAA) has been performed. A now 34 years old woman was admitted to our Clinic because of a RVF due to recto-sigmoid resection with colorectal anastomosis for endometriosis. An evaluation in anesthesia confirmed the RVF. In this case we avoided an immediate new colorectal anastomosis for the high risk of a recurrent anastomotic leakage and performed a DCAA. The outcome of the two-steps operation has been satisfactory both for the healing of the RVF and for the functional results bringing the young patient to a completely restored social, sexual and working life. In our opinion Turnbull-Cutait pull-through with delayed coloanal anastomosis is a good choice in patients with RVF in which a new colorectal or coloanal anastomosis can bring to a recurrent leakage. Delayed coloanal anastomosis, Deep endometriosis, Rectovaginal fistula.

  5. Anastomosis behavior differs between asymbiotic and symbiotic hyphae of Rhizophagus clarus.

    Science.gov (United States)

    Purin, Sonia; Morton, Joseph B

    2013-01-01

    The life history of arbuscular mycorrhizal fungi (AMF, Glomeromycota) consists of a short asymbiotic phase when spores germinate and a longer symbiotic phase where hyphae form a network within roots and subsequently in the rhizosphere. Hyphal anastomosis contributes to colony formation, yet this process has been studied mostly in the asymbiotic phase rather than in mycorrhizal plants because of methodological limitations. We sought to compare patterns of anastomosis during each phase of fungal growth by measuring hyphal fusions in genetically identical and different single spore isolates of Rhizophagus clarus from different environments and geographic locations. These isolates were genotyped with two anonymous markers of microsatellite-flanking regions. Anastomosis of hyphae from germinating spores was examined in axenic Petri dishes. A rhizohyphatron consisting of agar-coated glass slides bridging single or paired mycorrhizal sorghum plants allowed evaluation of anastomosis of symbiotic hyphae. Anastomosis of hyphae within a colony, defined here as a mycelium from an individual germinating spore or from mycorrhizal roots of one plant, occurred with similar frequencies (8-38%). However, anastomosis between paired colonies was observed in germinating spores from either genetically identical or different isolates, but it was never detected in symbiotic hyphae. The frequency of anastomosis in asymbiotic hyphae from paired interactions was low, occurring in fewer than 6% of hyphal contacts. These data suggest that anastomosis is relatively unconstrained when interactions occur within a colony but is confined to asymbiotic hyphae when interactions occur between paired colonies. This pattern of behavior suggests that asymbiotic and symbiotic phases of mycelium development by R. clarus may differ in function. Anastomosis in the asymbiotic phase may provide brief opportunities for gene flow between populations of this and possibly other AMF species.

  6. Lateral Nail Fold Incision Technique for Venous Anastomosis in Fingertip Replantation.

    Science.gov (United States)

    Jeon, Byung-Joon; Yang, Jae-Won; Roh, Si Young; Ki, Sae Hwi; Lee, Dong Chul; Kim, Jin Soo

    2016-01-01

    Successful venous anastomosis is one of the most important factors in fingertip replantation. Volar veins in the fingertip course proximally in a random pattern, which makes it difficult to find out the exact locations. Although dorsal veins in the lateral nail fold have constant location and adequate diameter for anastomosis, they have been known as hard to dissect from the immobile subcutaneous tissue. The authors present a new lateral nail fold incision technique for venous anastomosis in the fingertip amputations. From February 2010 to October 2010, 9 replantations using the new incision and venous anastomosis technique were performed in 9 patients. The levels of amputations were from the nail base to half of the nail bed. After repairing the proper digital arteries, a skin incision was made along the junction between the lateral nail fold and nail bed. Careful dissection was performed to isolate the veins in the lateral nail fold. After evaluation of the suitability of the vessel, venous anastomosis was performed. Seven male and 2 female patients were enrolled in this study. Appropriate dorsal veins for anastomosis could be found in 8 of 9 patients. All the replanted stumps survived without venous congestion and following additional procedures. A sizable volar or dorsal vein could not be found in 1 patient. The salvage technique was required in this patient. Dorsal veins in the lateral nail fold can be found easily because of the constant anatomical location. The new incision on the lateral nail fold provides not only sufficient operative field for anastomosis but also additional opportunity of successful venous anastomosis in the selected cases. The authors, therefore, propose this technique as an effective method for an alternative venous anastomosis in the zone I replantation.

  7. Interplay of magnetism and superconductivity in the compressed Fe-ladder compound BaFe2Se3

    Energy Technology Data Exchange (ETDEWEB)

    Ying, Jianjun; Lei, Hechang; Petrovic, Cedomir; Xiao, Yuming; Struzhkin, Viktor V. (BNL); (CIW)

    2017-06-01

    High pressure resistance, susceptibility, and Fe K β x-ray emission spectroscopy measurements were performed on Fe-ladder compound BaFe 2 Se 3 . Pressure-induced superconductivity was observed which is similar to the previously reported superconductivity in the BaFe 2 S 3 samples. The slope of local magnetic moment versus pressure shows an anomaly across the insulator-metal transition pressure in the BaFe 2 Se 3 samples. The local magnetic moment is continuously decreasing with increasing pressure, and the superconductivity appears only when the local magnetic moment value is comparable to the one in the iron-pnictide superconductors. Our results indicate that the compressed BaFe 2 C h 3 ( C h = S , Se) is a new family of iron-based superconductors. Despite the crystal structures completely different from the known iron-based superconducting materials, the magnetism in this Fe-ladder material plays a critical role in superconductivity. This behavior is similar to the other members of iron-based superconducting materials.

  8. [VEGF expression in dog retina after chorioretinal venous anastomosis].

    Science.gov (United States)

    Lu, Ning; Li, Zhihui; Sun, Xianli; Wang, Guanglu; Zhang, Feng; Peng, Xiaoyan

    2002-09-01

    To identify changes in vascular endothelial growth factor (VEGF) expression in the dog retina after laser-induced chorioretinal venous anastomosis (CRVA), in order to find out the relationship between CRVA treatment and the related neovascular complications. Immediately after branch retinal vein occlusion (BRVO) model was made in 5 eyes of 5 normal dogs, CRVA treatment was done over a small tributary vein in the drainage distribution of the occluded vein. In each eye, there were 2 - 3 treatment sites. Four to six weeks later, a repeated treatment was given if the first treatment failed to show the anastomosis. The treatment sites with successful CRVA were divided into two groups: the small laser spot group, which received one treatment and the big laser spot group, which received more than one treatment. The expression of VEGF was investigated immunohistochemically in the treatment sites with successful anastomoses and in the 5 normal fellow eyes (control). There were totally 10 successful anastomoses in the 5 experimental eyes, among which, five received one treatment and the other 5 received more than one treatment. On fundus examination, the small laser spots were round and small, and the big laser spots were large with local proliferation. VEGF immunoreactivity was absent/weak in the normal dog retina, and remained unchanged in the small laser spot group, but somewhat increased in the big laser spot group. No neovascular complications occurred. All immunostaining experiments were accompanied by proper controls and none of the negative controls showed any immunoreactivity. Proper laser treatment can induce CRVA quite safely in nonischemic dog retina, which does not cause changes in the expression of VEGF, but severe laser damage in the treatment site can cause increased VEGF expression which may be related to neovascular complications.

  9. Hemodynamic evaluation before and after the STA-MCA anastomosis

    International Nuclear Information System (INIS)

    Touho, Hajime; Karasawa, Jun; Shishido, Hisashi; Yamada, Keisuke; Shibamoto, Keiji

    1990-01-01

    Twenty-seven patients with minor completed and major stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The regional cerebral blood flow (rCBF), using inhalation of stable xenon and computed tomographic scanning (Xe s CT-CBF study), and the mode of transit time (MTT) in the MCA territory using intra-arterial digital aortography were measured. Activated rCBF and MTT was measured 20 minutes after the administration of acetazolamide (10 mg/kg) in 14 patients. Nineteen of the 23 patients with minor stroke (Group 1) showed immediate improvement in their neurological state within a few days of the operation, while four patients with minor stroke (Group 2) and four patients with major stroke (Group 3) showed no improvement. Based on the rCBF obtained with the Xe s CT-CBF study, affected side rCBF/unaffected side rCBF and %f [(peak DSA number/affected side MTT)/(peak DSA number/unaffected side MTT)] were compared. There was a significant positive correlation. Affected side MTT in Group 1 was 6.41±1.16 sec, preoperatively, and significantly decreased to 5.13±0.91 sec after the operation. On the other hand, preoperative MTT in Group 2 was 4.40±0.81 sec and 4.76±0.89 sec, postoperatively. Preoperative %f in Group 1 was 0.514±0.143 and significantly increased to 0.739±0.154, postoperatively. Group 2 showed no change. Vasodilatory capacity with acetazolamide showed a marked improvement in Group 1, postoperativery. Our study indicated that if MTT is moderately lengthened, %f is moderately decreased, and vasodilatory capacity is impaired, in patients with minor ischemic stroke will benefit from STA-MCA anastomosis. (author)

  10. Fingertip Reconstruction Using Free Toe Tissue Transfer Without Venous Anastomosis

    Directory of Open Access Journals (Sweden)

    Won Young Yoon

    2012-09-01

    Full Text Available BackgroundThis study was designed to introduce the feasibility of toe tissue transfer without venous outflow for fingertip reconstruction.MethodsFive cases of fingertip defects were treated successfully with this method. Four cases were traumatic fingertip defects, and one case was a hook-nail deformity. The lateral pulp of a great toe or medioinferior portion of a second toe was used as the donor site. An arterial pedicle was dissected only within the digit and anastomosis was performed within 2 cm around the defect margin. The digital nerve was repaired simultaneously. No additional dissection of the dorsal or volar pulp vein was performed in either the donor or recipient sites. Other surgical procedures were performed following conventional techniques. Postoperative venous congestion was monitored with pulp temperature, color, and degree of tissue oxygen saturation. Venous congestion was decompressed with a needle-puncture method intermittently, but did not require continuous external bleeding for salvage.ResultsVenous congestion was observed in all the flaps, but improved within 3 or 4 days postoperatively. The flap size was from 1.5×1.5 cm2 to 2.0×3.0 cm2. The mean surgical time was 2 hours and 20 minutes. A needle puncture was carried out every 2 hours during the first postoperative day, and then every 4 hours thereafter. The amount of blood loss during each puncture procedure was less than 0.2 mL. In the long-term follow-up, no flap atrophy was observed.ConclusionsWhen used properly, the free toe tissue transfer without venous anastomosis method can be a treatment option for small defects on the fingertip area.

  11. Myofibroblasts and colonic anastomosis healing in Wistar rats

    Directory of Open Access Journals (Sweden)

    Vasiliadou Kalliopi

    2011-03-01

    Full Text Available Abstract Background The myofibroblasts play a central role in wound healing throughout the body. The process of wound healing in the colon was evaluated with emphasis on the role of myofibroblasts. Methods One hundred male Wistar rats weighing 274 ± 9.1 g (mean age: 3.5 months were used. A left colonic segment was transected and the colon was re-anastomosed. Animals were randomly divided into two groups. The first group experimental animals (n = 50 were sacrificed on postoperative day 3, while the second group rats (n = 50 were sacrificed on postoperative day 7. Healing of colonic anastomosis was studied in terms of anastomotic bursting pressure, as well as myofibroblastic reaction and expression of α-smooth muscle actin (α-SMA, adhesion formation, inflammatory reaction and neovascularization. Results The mean anastomotic bursting pressure increased from 20.6 ± 3.5 mmHg on the 3rd postoperative day to 148.8 ± 9.6 Hg on the 7th postoperative day. Adhesion formation was increased on the 7th day, as compared to the 3rd day. In addition, the myofibroblastic reaction was more profound on the 7th postoperative day in comparison with the 3rd postoperative day. The staining intensity for α-SMA was progressive from the 3rd to the 7th postoperative day. On the 7th day the α-SMA staining in the myofibroblats reached the level of muscular layer cells. Conclusions Our study emphasizes the pivotal role of myofibroblasts in the process of colonic anastomosis healing. The findings provide an explanation for the reduction in the incidence of wound dehiscence after the 7th postoperative day.

  12. Compressed Gas Safety for Experimental Fusion Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee C. Cadwallader

    2004-09-01

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air, and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard assoicated with compressed gas cylinders and mthods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  13. MAGNET

    CERN Multimedia

    by B. Curé

    2011-01-01

    The magnet operation was very satisfactory till the technical stop at the end of the year 2010. The field was ramped down on 5th December 2010, following the successful regeneration test of the turbine filters at full field on 3rd December 2010. This will limit in the future the quantity of magnet cycles, as it is no longer necessary to ramp down the magnet for this type of intervention. This is made possible by the use of the spare liquid Helium volume to cool the magnet while turbines 1 and 2 are stopped, leaving only the third turbine in operation. This obviously requires full availability of the operators to supervise the operation, as it is not automated. The cryogenics was stopped on 6th December 2010 and the magnet was left without cooling until 18th January 2011, when the cryoplant operation resumed. The magnet temperature reached 93 K. The maintenance of the vacuum pumping was done immediately after the magnet stop, when the magnet was still at very low temperature. Only the vacuum pumping of the ma...

  14. Fingertip replantation using a single volar arteriovenous anastomosis and drainage with a transverse tip incision.

    Science.gov (United States)

    Yabe, T; Muraoka, M; Motomura, H; Ozawa, T

    2001-11-01

    Four cases of fingertip replantation using a single volar arteriovenous anastomosis and drainage with a transverse tip incision are reported. Because of lack of suitable arteries for anastomosis in the amputated finger, in each case a volar radial vein was anastomosed to the proximal digital artery and external drainage was performed through a transverse tip incision. In 3 cases the replanted fingertip survived completely; partial necrosis occurred in 1 case. Because veins are more superficial and larger than arteries, they are more available for anastomosis. The results indicate that this method is a useful alternative in fingertip replantation.

  15. Spinal cord compression at C1-C2 level due to tophaceous gout (magnetic resonance imaging and computed tomography cisternographic findings)

    International Nuclear Information System (INIS)

    Vries, C. de; Slegte, R.G.M. de; Valk, J.

    1987-01-01

    The authors report a case of spinal cord compression at the level of the foramen magnum due to tophaceous gout in a patient with no clinical history of gout. The presence of a foramen magnum mass due to urate crystal deposition in a patient without clinical history of gout or additional bone abnormalities has, to the best of the authors' knowledge, never been described before. In the case presented here, no bone changes were encountered with CT or MRI. Neither the presence of small high-density punctuations on the CT examination nor the signal intensities of the mass on T1- and T2-weighted images led to the radiological diagnois of tophaceous gout. The foramen magnum mass and the spinal cord compression were, however, beautifully depicted by both modalities. 14 refs.; 2 figs

  16. Intra-corporeal anastomosis in laparoscopic surgery for benign colorectal disease

    DEFF Research Database (Denmark)

    Antonsen, Jacob; Balachandran, Rogini; Holm, Finn Stigsen

    2017-01-01

    INTRODUCTION: Recent studies have described the benefits of performing bowel resections for benign and malignant diseases as a total laparoscopic procedure with intra-corporeal anastomosis. We describe our preliminary experience with total laparoscopic surgery for benign lower gastrointestinal...

  17. [Robotic-assisted minimally invasive abdominothoracal oesophageal resection with intrathoracic anastomosis].

    Science.gov (United States)

    Egberts, J-H; Aselmann, H; Schafmayer, C; Jünemann, K-P; Becker, T

    2014-02-01

    Ivor Lewis oesophagectomy is one of the approaches used worldwide for treating oesophageal cancer. The adoption of minimally invasive oesophagectomy has increased worldwide since its first description more than 15 years ago. However, minimally invasive oesophagectomy with a chest anastomosis has advantages. By using a four-arm robotic platform, not only the preparation of the gastric tube and mobilisation of the oesophagus but also the intrathoracic anastomosis of the oesophagogastrostomy can be performed in a comfortable and safe way. The indication for oesophageal resection is oesophageal cancer. The operative procedure comprises robotic-assisted abdominothoracal oesophageal resection with reconstruction by a gastric tube and intrathoracic anastomosis (Ivor Lewis procedure). Robotic abdominal and thoracic minimally invasive esophagectomy is feasible, and safe with a complete lymph node dissection. Especially the intrathoracic anastomosis of the oesophagogastrostomy can be performed in a comfortable and safe way. Georg Thieme Verlag KG Stuttgart · New York.

  18. Tracheal resection and anastomosis after traumatic tracheal stenosis in a horse.

    Science.gov (United States)

    Barnett, Timothy P; Hawkes, Claire S; Dixon, Padraic M

    2015-02-01

    To report a resection and anastomosis technique to treat trauma-induced tracheal stenosis. Case report. A 9-year-old Warmblood gelding. Endoscopy, radiography, and ultrasonography were used to diagnose a single ring tracheal stenosis; the stenotic region was resected and adjacent tracheal rings anastomosed with an end-to-end technique. The anastomosis healed completely despite formation of a unilateral partial mucosal stenosis "web," which was subsequently removed by transendoscopic laser surgery. During tracheal anastomosis, the left recurrent laryngeal nerve was damaged, causing laryngeal hemiplegia, later treated successfully by laryngoplasty. The horse returned to its previous level of work. This tracheal resection and anastomosis technique successfully provided the horse with a large tracheal lumen, and despite major complications, allowed a return to full athletic work. © Copyright 2014 by The American College of Veterinary Surgeons.

  19. Chorioretinal anastomosis after photodynamic therapy for polypoidal choroidal vasculopathy: CRA after PDT for PCV.

    Science.gov (United States)

    Yodoi, Yuko; Tsujikawa, Akitaka; Otani, Atsushi; Aikawa, Hiroko; Yoshimura, Nagahisa

    2008-08-01

    An 80-year-old woman was treated with photodynamic therapy (PDT) to the left eye for polypoidal choroidal vasculopathy (PCV). About 3 months after PDT, her left eye developed a chorioretinal anastomosis with severe atrophy of the retinal pigment epithelium in the macula; visual acuity in this eye was 20/1000. She received a second session of PDT, plus an intravitreal injection of triamcinolone acetonide. About 3 months after the second treatment, the chorioretinal anastomosis was enlarged and the retinal vessels involved in the anastomosis were more dilated. About 1 year after the first PDT, visual acuity in the left eye had stabilized at 20/400. Development of a chorioretinal anastomosis is a distinct possibility following PDT in eyes with PCV, and can lead to poor visual recovery.

  20. J-pouch ileoanal anastomosis in children and adolescents with ulcerative colitis

    DEFF Research Database (Denmark)

    Wewer, Vibeke; Hesselfeldt, Peter; Qvist, Niels

    2005-01-01

    OBJECTIVES: The aim of this study was to evaluate, over a 10-year period, severe surgical complications, functional outcome, patient satisfaction and impact on social life after colectomy and J-pouch ileoanal anastomosis for children and adolescents

  1. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    Operation of the magnet has gone quite smoothly during the first half of this year. The magnet has been at 4.5K for the full period since January. There was an unplanned short stop due to the CERN-wide power outage on May 28th, which caused a slow dump of the magnet. Since this occurred just before a planned technical stop of the LHC, during which access in the experimental cavern was authorized, it was decided to leave the magnet OFF until 2nd June, when magnet was ramped up again to 3.8T. The magnet system experienced a fault also resulting in a slow dump on April 14th. This was triggered by a thermostat on a filter choke in the 20kA DC power converter. The threshold of this thermostat is 65°C. However, no variation in the water-cooling flow rate or temperature was observed. Vibration may have been the root cause of the fault. All the thermostats have been checked, together with the cables, connectors and the read out card. The tightening of the inductance fixations has also been checked. More tem...

  2. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet was energised at the beginning of March 2012 at a low current to check all the MSS safety chains. Then the magnet was ramped up to 3.8 T on 6 March 2012. Unfortunately two days later an unintentional switch OFF of the power converter caused a slow dump. This was due to a misunderstanding of the CCC (CERN Control Centre) concerning the procedure to apply for the CMS converter control according to the beam-mode status at that time. Following this event, the third one since 2009, a discussion was initiated to define possible improvement, not only on software and procedures in the CCC, but also to evaluate the possibility to upgrade the CMS hardware to prevent such discharge from occurring because of incorrect procedure implementations. The magnet operation itself was smooth, and no power cuts took place. As a result, the number of magnetic cycles was reduced to the minimum, with only two full magnetic cycles from 0 T to 3.8 T. Nevertheless the magnet suffered four stops of the cryogeni...

  3. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      Following the unexpected magnet stops last August due to sequences of unfortunate events on the services and cryogenics [see CMS internal report], a few more events and initiatives again disrupted the magnet operation. All the magnet parameters stayed at their nominal values during this period without any fault or alarm on the magnet control and safety systems. The magnet was stopped for the September technical stop to allow interventions in the experimental cavern on the detector services. On 1 October, to prepare the transfer of the liquid nitrogen tank on its new location, several control cables had to be removed. One cable was cut mistakenly, causing a digital input card to switch off, resulting in a cold-box (CB) stop. This tank is used for the pre-cooling of the magnet from room temperature down to 80 K, and for this reason it is controlled through the cryogenics control system. Since the connection of the CB was only allowed for a field below 2 T to avoid the risk of triggering a fast d...

  4. DNABIT Compress – Genome compression algorithm

    OpenAIRE

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our ...

  5. Use of 5-mm Laparoscopic Stapler to Perform Open Small Bowel Anastomosis in a Neonatal Animal Model.

    Science.gov (United States)

    Glenn, Ian C; Bruns, Nicholas E; Ponsky, Todd A

    2016-10-01

    While adult bowel anastomoses are typically performed with staplers, neonatal small bowel anastomoses have traditionally been performed in a hand-sewn manner due to the large size of surgical staplers. The purpose of this study was to compare stapled anastomosis using a newly available, 5-mm laparoscopic stapler to a hand-sewn anastomosis in an open animal model. Twenty anastomoses were performed by two general surgery residents (10 stapled and 10 hand-sewn) in an adult New Zealand white rabbit. The small bowel was divided with a scalpel. Surgical technique was alternated between single-layer hand-sewn and stapled anastomoses. Each anastomosis was resected for ex vivo testing. Measurements collected were outer diameter of the bowel before division, time to perform the anastomosis, anastomosis inner diameter (ID), and leak test. IDs were measured by cutting the anastomosis in cross-section, taking a photograph, and measuring the diameter by computer software. In addition, the surgeons qualitatively evaluated the anastomoses for hemostasis and overall quality. Statistical significance was determined using the Student's t-test. There were statistically significant differences between stapled and hand-sewn anastomosis, respectively, for average operative time (4 minutes 2 seconds versus 16 minutes 6 seconds, P animal model, a 5-mm stapled anastomosis is an acceptable alternative to hand-sewn small bowel anastomosis. The stapler is faster and creates a larger diameter anastomosis, however, there was one leak when closing the enterotomy in the stapled group and overlapping staple lines should be avoided.

  6. Comparison of laparoscopic and conventional surgery of intestinal anastomosis in dogs

    OpenAIRE

    O. J. Ali; B. T. Abass

    2008-01-01

    The aim of this study was to evaluate operative laparoscopy in comparison with conventional laparotomy for intestinal resection and anastomosis in dogs. Eighteen adult dogs were equally and randomly divided into 3 groups: Group I: Intestinal anastomosis was performed extracorporeally, by laparoscopic-assisted surgery, in which a 5cm loop of small bowel was exteriorized through a mini-laparotomy opening (an enlarged trocar incision 1.5-2 cm in length), then surgically resected and anastomosed ...

  7. Fingertip replantation (zone I) without venous anastomosis: clinical experience and outcome analysis

    OpenAIRE

    Huan, An-shi; Regmi, Subhash; Gu, Jia-xiang; Liu, Hong-jun; Zhang, Wen-zhong

    2016-01-01

    Purpose The purpose of this study was to report our experience of fingertip replantation without venous anastomosis using alternate method to counter post-operative venous congestion. Methods 30 Patients (18 men and 12 women) with 30 fingertip amputations (Tamai zone I) were treated with artery-only anastomosis fingertip replantation between March 2010 and July 2014. Postoperative venous outflow was maintained by allowing bleeding through wound gaps combined with topical (12500u:250mlNS) and ...

  8. DNABIT Compress – Genome compression algorithm

    Science.gov (United States)

    Rajarajeswari, Pothuraju; Apparao, Allam

    2011-01-01

    Data compression is concerned with how information is organized in data. Efficient storage means removal of redundancy from the data being stored in the DNA molecule. Data compression algorithms remove redundancy and are used to understand biologically important molecules. We present a compression algorithm, “DNABIT Compress” for DNA sequences based on a novel algorithm of assigning binary bits for smaller segments of DNA bases to compress both repetitive and non repetitive DNA sequence. Our proposed algorithm achieves the best compression ratio for DNA sequences for larger genome. Significantly better compression results show that “DNABIT Compress” algorithm is the best among the remaining compression algorithms. While achieving the best compression ratios for DNA sequences (Genomes),our new DNABIT Compress algorithm significantly improves the running time of all previous DNA compression programs. Assigning binary bits (Unique BIT CODE) for (Exact Repeats, Reverse Repeats) fragments of DNA sequence is also a unique concept introduced in this algorithm for the first time in DNA compression. This proposed new algorithm could achieve the best compression ratio as much as 1.58 bits/bases where the existing best methods could not achieve a ratio less than 1.72 bits/bases. PMID:21383923

  9. Esophageal-gastric anastomosis in radical resection of esophageal cancer under thoracoscopy combined with laparoscopy.

    Science.gov (United States)

    Hao, Zhang; Zhenya, Shen; Lei, Wang

    2014-10-01

    To determine the feasibility of esophagogastric anastomosis in esophageal cancer radical resection under thoracoscopy combined with laparoscopy in terms of complications and operation time. Experimental study. Department of Thoracic Surgery, Affiliated with The First Hospital, Suzhou University, from June 2008 to June 2012. Clinical data of 136 patients operated for esophageal cancer by radical resection under thoracoscopy combined with laparoscopy was analyzed. Eighty one superior and middle segment esophageal carcinoma patients were operated through right thoracoscope, abdominoscope, and neck incision. The esophagogastric anastomosis was completed in the left side of neck by handiwork. Fifty five inferior segment esophageal carcinoma were operated through right thoracoscope, abdominoscope and the esophagogastric anastomosis was completed with stapler in right thoracic cavity through superior belly incision and diaphragmatic hiatus. The operation time and the intra-operative blood loss in patients with intrathoracic mechanical anastomosis was significantly lower than that of cervical anastomosis. Other variables were not significantly different. The practicability of this method of anastomosis that completed with stapler in right thoracic cavity through superior belly incision and diaphragmatic hiatus had been well confirmed.

  10. Esophageal - Gastric Anastomosis in Radical Resection of Esophageal Cancer under Thoracoscopy Combined with Laparoscopy

    International Nuclear Information System (INIS)

    Hao, Z.; Lei, W.; Zhenya, S.

    2014-01-01

    Objective: To determine the feasibility of esophagogastric anastomosis in esophageal cancer radical resection under thoracoscopy combined with laparoscopy in terms of complications and operation time. Study Design: Experimental study. Place and Duration of Study: Department of Thoracic Surgery, Affiliated with The First Hospital, Suzhou University, from June 2008 to June 2012. Methodology: Clinical data of 136 patients operated for esophageal cancer by radical resection under thoracoscopy combined with laparoscopy was analyzed. Eighty one superior and middle segment esophageal carcinoma patients were operated through right thoracoscope, abdominoscope, and neck incision. The esophagogastric anastomosis was completed in the left side of neck by handiwork. Fifty five inferior segment esophageal carcinoma were operated through right thoracoscope, abdominoscope and the esophagogastric anastomosis was completed with stapler in right thoracic cavity through superior belly incision and diaphragmatic hiatus. Results: The operation time and the intra-operative blood loss in patients with intrathoracic mechanical anastomosis was significantly lower than that of cervical anastomosis. Other variables were not significantly different. Conclusion: The practicability of this method of anastomosis that completed with stapler in right thoracic cavity through superior belly incision and diaphragmatic hiatus had been well confirmed. (author)

  11. Deep organ space infection after emergency bowel resection and anastomosis: The anatomic site does not matter.

    Science.gov (United States)

    Benjamin, Elizabeth; Siboni, Stefano; Haltmeier, Tobias; Inaba, Kenji; Lam, Lydia; Demetriades, Demetrios

    2015-11-01

    Deep organ space infection (DOSI) is a serious complication after emergency bowel resection and anastomosis. The aim of this study was to identify the incidence and risk factors for the development of DOSI. National Surgical Quality Improvement Program database study including patients who underwent large bowel or small bowel resection and primary anastomosis. The incidence, outcomes, and risk factors for DOSI were evaluated using univariate and multivariate analyses. A total of 87,562 patients underwent small bowel, large bowel, or rectal resection and anastomosis. Of these, 14,942 (17.1%) underwent emergency operations and formed the study population. The overall mortality rate in emergency operations was 12.5%, and the rate of DOSI was 5.6%. A total of 18.0% required ventilatory support in more than 48 hours, and 16.0% required reoperation. Predictors of DOSI included age, steroid use, sepsis or septic shock on admission, severe wound contamination, and advanced American Society of Anesthesiologists classification. The anatomic location of resection and anastomosis was not significantly associated with DOSI. Patients undergoing emergency bowel resection and anastomosis have a high mortality, risk of DOSI, and systemic complications. Independent predictors of DOSI include wound and American Society of Anesthesiologists classification, sepsis or septic shock on admission, and steroid use. The anatomic location of resection and anastomosis was not significantly associated with DOSI. Epidemiologic/prognostic study, level III.

  12. Basic interrupted versus continuous suturing techniques in bronchial anastomosis following sleeve lobectomy in dogs.

    Science.gov (United States)

    Bayram, Ahmet Sami; Erol, Mehmet Muharrem; Salci, Hakan; Ozyiğit, Ozgür; Görgül, Sacit; Gebitekin, Cengiz

    2007-12-01

    Sleeve resection with or without lung resection is a valid conservative operation for patients with benign or malignant tumors; it enables the preservation of lung parenchyma. The aim of this prospective randomized study was to compare complications, operating time, and bronchial healing between the techniques of interrupted and continuous suturing for bronchial anastomosis in dogs. Twenty adult mongrel dogs each weighing 18-22 kg (average: 20 kg) were divided into two groups according to the anastomosis technique performed: group A, interrupted suturing and group B, continuous suturing. Each group comprised of 10 dogs. Following right thoracotomy, sleeve resection of the right cranial lobe was performed in all dogs. Basic interrupted sutures using 4/0 Vicryl (Ethicon, USA) were used in group A, and continuous sutures were used in group B. The median anastomosis time was 15.2 min (range: 13-21 min) in group A and 9.6 min (range: 8-13 min) in group B. In all dogs, the anastomosis line was resected via right pneumonectomy for histopathological investigation 1 month after sleeve resection. Histopathological examination revealed that the healing of the anastomosis was not affected by the suturing technique applied. One dog from each group died on the fourth postoperative day; Fisher's exact test, p=0.763. Our research revealed that the healing of the anastomosis was not affected by the suturing technique performed.

  13. Intrathoracic versus cervical anastomosis and predictors of anastomotic leakage after oesophagectomy for cancer.

    Science.gov (United States)

    Gooszen, J A H; Goense, L; Gisbertz, S S; Ruurda, J P; van Hillegersberg, R; van Berge Henegouwen, M I

    2018-04-01

    Studies comparing the anastomotic leak rate in patients with an intrathoracic versus a cervical anastomosis after oesophagectomy are equivocal. The aim of this study was to compare clinical outcome after oesophagectomy in patients with an intrathoracic or cervical anastomosis, and to identify predictors of anastomotic leakage in a nationwide audit. Between January 2011 and December 2015, all consecutive patients who underwent oesophagectomy for cancer were identified from the Dutch Upper Gastrointestinal Cancer Audit. For the comparison between an intrathoracic and cervical anastomosis, propensity score matching was used to adjust for potential confounders. Multivariable logistic regression modelling with backward stepwise selection was used to determine independent predictors of anastomotic leakage. Some 3348 patients were included. After propensity score matching, 654 patients were included in both the cervical and intrathoracic anastomosis groups. An intrathoracic anastomosis was associated with a lower leak rate than a cervical anastomosis (17·0 versus 21·9 per cent; P = 0·025). The percentage of patients with recurrent nerve paresis was also lower (0·6 versus 7·0 per cent; P Risk factors for anastomotic leak were co-morbidities and proximal tumours. © 2018 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

  14. Fingertip Replantation Without and With Palmar Venous Anastomosis: Analysis of the Survival Rates and Vein Distribution.

    Science.gov (United States)

    Aksoy, Alper; Gungor, Melike; Sir, Emin

    2017-01-01

    The purpose of this study was to compare the results of fingertip replantations without (artery anastomosis only replantations) and with venous anastomosis (replantations in which both arterial and palmar venous anastomoses were performed). Also, distribution of the veins used for anastomosis was analyzed retrospectively. First 53 digits (47 patients) received only arterial anastomosis (group 1). For relieving venous congestion, external bleeding method was used. Last 41 digits (38 patients) received both arterial and palmar venous anastomoses without external bleeding (group 2). There was statistical significance of the survival rate between group 1 [77.3% (41/53)] and group 2 [92.6% (38/41)] (P = 0.039). Venous congestion was encountered at 10 digits in group 1 (all underwent necrosis totally) and at 3 digits in group 2 (both were moderate and could be salvaged partially) (P = 0.094, no statistical significance). There was statistical significance of the mean operation time for single-fingertip replantation between group 1 (80 ± 7.8 minutes) and group 2 (105 ± 14.5 minutes) (P replantations with palmar venous anastomosis have simpler postoperative care and lower drawbacks as compared with artery anastomosis-only replantations.

  15. [Extrinsic compression of the hepatocholedocus caused by cavernomatosis of the portal vein. Report of a case].

    Science.gov (United States)

    Carpani, M; Guma, C I; Casal, M A

    1982-01-01

    The extrinsic compression of the hepatocholedochus by a cavernomatosis of the portal vein, is an unusual pathology. The present case begun clinically as an obstructive jaundice, assuming that the vascular origin of the compression increased the litiasic biliary disease. The percutaneous transhepatic cholangiography was the diagnostic method that suggested a double illness of the biliary system. The surgery and the pathology certificated the diagnosis. The correct treatment once confirmed the obstructive trial, must be: the extraction of the biliary gallstones and the bile-digestive derivation (preferently the hepatic-jejunum anastomosis in Y of Roux).

  16. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet and its sub-systems were stopped at the beginning of the winter shutdown on 8th December 2011. The magnet was left without cooling during the cryogenics maintenance until 17th January 2012, when the cryoplant operation resumed. The magnet temperature reached 93 K. The vacuum pumping was maintained during this period. During this shutdown, the yearly maintenance was performed on the cryogenics, the vacuum pumps, the magnet control and safety systems, and the power converter and discharge lines. Several preventive actions led to the replacement of the electrovalve command coils, and the 20A DC power supplies of the magnet control system. The filters were cleaned on the demineralised water circuits. The oil of the diffusion pumps was changed. On the cryogenics, warm nitrogen at 343 K was circulated in the cold box to regenerate the filters and the heat exchangers. The coalescing filters have been replaced at the inlet of both the turbines and the lubricant trapping unit. The active cha...

  17. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

      The magnet was operated without any problem until the end of the LHC run in February 2013, apart from a CERN-wide power glitch on 10 January 2013 that affected the CMS refrigerator, causing a ramp down to 2 T in order to reconnect the coldbox. Another CERN-wide power glitch on 15 January 2013 didn’t affect the magnet subsystems, the cryoplant or the power converter. At the end of the magnet run, the reconnection of the coldbox at 2.5 T was tested. The process will be updated, in particular the parameters of some PID valve controllers. The helium flow of the current leads was reduced but only for a few seconds. The exercise will be repeated with the revised parameters to validate the automatic reconnection process of the coldbox. During LS1, the water-cooling services will be reduced and many interventions are planned on the electrical services. Therefore, the magnet cryogenics and subsystems will be stopped for several months, and the magnet cannot be kept cold. In order to avoid unc...

  18. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet was successfully operated at the end of the year 2009 despite some technical problems on the cryogenics. The magnet was ramped up to 3.8 T at the end of November until December 16th when the shutdown started. The magnet operation met a few unexpected stops. The field was reduced to 3.5 T for about 5 hours on December 3rd due to a faulty pressure sensor on the helium compressor. The following day the CERN CCC stopped unintentionally the power converters of the LHC and the experiments, triggering a ramp down that was stopped at 2.7 T. The magnet was back at 3.8 T about 6 hours after CCC sent the CERN-wide command. Three days later, a slow dump was triggered due to a stop of the pump feeding the power converter water-cooling circuit, during an intervention on the water-cooling plant done after several disturbances on the electrical distribution network. The magnet was back at 3.8 T in the evening the same day. On December 10th a break occurred in one turbine of the cold box producing the liquid ...

  19. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The CMS magnet has been running steadily and smoothly since the summer, with no detected flaw. The magnet instrumentation is entirely operational and all the parameters are at their nominal values. Three power cuts on the electrical network affected the magnet run in the past five months, with no impact on the data-taking as the accelerator was also affected at the same time. On 22nd June, a thunderstorm caused a power glitch on the service electrical network. The primary water cooling at Point 5 was stopped. Despite a quick restart of the water cooling, the inlet temperature of the demineralised water on the busbar cooling circuit increased by 5 °C, up to 23.3 °C. It was kept below the threshold of 27 °C by switching off other cooling circuits to avoid the trigger of a slow dump of the magnet. The cold box of the cryogenics also stopped. Part of the spare liquid helium volume was used to maintain the cooling of the magnet at 4.5 K. The operators of the cryogenics quickly restarted ...

  20. Clinical Feasibility of Free-Breathing Dynamic T1-Weighted Imaging With Gadoxetic Acid-Enhanced Liver Magnetic Resonance Imaging Using a Combination of Variable Density Sampling and Compressed Sensing.

    Science.gov (United States)

    Yoon, Jeong Hee; Yu, Mi Hye; Chang, Won; Park, Jin-Young; Nickel, Marcel Dominik; Son, Yohan; Kiefer, Berthold; Lee, Jeong Min

    2017-10-01

    The purpose of the study was to investigate the clinical feasibility of free-breathing dynamic T1-weighted imaging (T1WI) using Cartesian sampling, compressed sensing, and iterative reconstruction in gadoxetic acid-enhanced liver magnetic resonance imaging (MRI). This retrospective study was approved by our institutional review board, and the requirement for informed consent was waived. A total of 51 patients at high risk of breath-holding failure underwent dynamic T1WI in a free-breathing manner using volumetric interpolated breath-hold (BH) examination with compressed sensing reconstruction (CS-VIBE) and hard gating. Timing, motion artifacts, and image quality were evaluated by 4 radiologists on a 4-point scale. For patients with low image quality scores (XD]) reconstruction was additionally performed and reviewed in the same manner. In addition, in 68.6% (35/51) patients who had previously undergone liver MRI, image quality and motion artifacts on dynamic phases using CS-VIBE were compared with previous BH-T1WIs. In all patients, adequate arterial-phase timing was obtained at least once. Overall image quality of free-breathing T1WI was 3.30 ± 0.59 on precontrast and 2.68 ± 0.70, 2.93 ± 0.65, and 3.30 ± 0.49 on early arterial, late arterial, and portal venous phases, respectively. In 13 patients with lower than average image quality (XD-reconstructed CS-VIBE) significantly reduced motion artifacts (P XD reconstruction showed less motion artifacts and better image quality on precontrast, arterial, and portal venous phases (P < 0.0001-0.013). Volumetric interpolated breath-hold examination with compressed sensing has the potential to provide consistent, motion-corrected free-breathing dynamic T1WI for liver MRI in patients at high risk of breath-holding failure.

  1. Radiologic image compression -- A review

    International Nuclear Information System (INIS)

    Wong, S.; Huang, H.K.; Zaremba, L.; Gooden, D.

    1995-01-01

    The objective of radiologic image compression is to reduce the data volume of and to achieve a lot bit rate in the digital representation of radiologic images without perceived loss of image quality. However, the demand for transmission bandwidth and storage space in the digital radiology environment, especially picture archiving and communication systems (PACS) and teleradiology, and the proliferating use of various imaging modalities, such as magnetic resonance imaging, computed tomography, ultrasonography, nuclear medicine, computed radiography, and digital subtraction angiography, continue to outstrip the capabilities of existing technologies. The availability of lossy coding techniques for clinical diagnoses further implicates many complex legal and regulatory issues. This paper reviews the recent progress of lossless and lossy radiologic image compression and presents the legal challenges of using lossy compression of medical records. To do so, the authors first describe the fundamental concepts of radiologic imaging and digitization. Then, the authors examine current compression technology in the field of medical imaging and discuss important regulatory policies and legal questions facing the use of compression in this field. The authors conclude with a summary of future challenges and research directions. 170 refs

  2. The effects of ghrelin on colonic anastomosis healing in rats

    Directory of Open Access Journals (Sweden)

    Canan Ceran

    2013-01-01

    Full Text Available OBJECTIVES: In addition to its roles in the stimulation of growth hormone secretion and the regulation of appetite and metabolism, ghrelin exerts immunomodulatory, anti-inflammatory and antioxidant actions in several organ systems. In this study, we investigated the effects of ghrelin on the healing of experimental colonic anastomoses. METHODS: Wistar rats were randomly divided into two groups (n = 10 in each. A segment of colon was excised, and an end-to-end anastomosis was performed in the distal colon. The Ghrelin Group received 10 ng/kg/day IP ghrelin for seven days postoperatively, whereas the Control Group received an identical volume of saline. On the seventh postoperative day, the anastomotic bursting pressures and hydroxyproline levels were measured, and adhesion formation around the anastomoses was examined. Histopathological analyses were performed to evaluate inflammatory cell infiltration, fibroblast infiltration, collagen density and neovascularization. RESULTS: In the Ghrelin Group, the bursting pressure and hydroxyproline levels were significantly higher than in the Control Group. The adhesion formation scores were lower in the Ghrelin Group than in the Control Group. Although the inflammatory cell infiltration was diminished in the Ghrelin Group, the degrees of fibroblast infiltration, collagen density and neovascularization were not significantly different between the groups. CONCLUSION: Our results indicate that ghrelin improves the healing of colonic anastomoses in rats.

  3. Acute Cholangitis After Bilioenteric Anastomosis for Bile Duct Injuries.

    Science.gov (United States)

    Ortiz-Brizuela, Edgar; Sifuentes-Osornio, José; Manzur-Sandoval, Daniel; Terán-Ellis, Santiago Mier Y; Ponce-de-León, Sergio; Torres-González, Pedro; Mercado, Miguel Ángel

    2017-10-01

    The study aims to describe the clinical features, microbiology, and associated factors of acute cholangitis (AC) after bilioenteric anastomosis (BEA) for biliary duct injury (BDI). Additionally, we assessed the performance of the Tokyo Guidelines 2013 (TG13) recommendations in these patients. We conducted a case-control study of 524 adults with a history of BEA for BDI from January 2000 to January 2014. A propensity score adjustment was performed for the analysis of the independent role of the main factors identified during the univariate logistic regression procedure. We identified 117 episodes of AC in 70 patients; 51.3% were definitive AC according to the TG13 diagnostic criteria, and 39.3% did not fulfill the imaging criteria of AC. A history of post-operative biliary complications (OR 2.55, 95% CI 1.38-4.70) and the bile duct confluence preservation (OR 0.46, 95% CI 0.24-0.87) were associated with AC. Eighty-nine percent of the microorganisms were Enterobacteriaceae; of them, 28% were extended spectrum β-lactamase (ESBL) producers. AC is a common complication after BEA and must be suspected even in the absence of imaging findings, particulary in patients with a history of post-operative biliary complications, and/or without bile duct confluence preserved. An empirical treatment for ESBL-producing Enterobacteriaceae may be appropriate in patients living in countries with a high rate of bacterial drug resistance.

  4. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The magnet ran smoothly in the last few months until a fast dump occurred on 9th May 2011. Fortunately, this occurred in the afternoon of the first day of the technical stop. The fast dump was due to a valve position controller that caused the sudden closure of a valve. This valve is used to regulate the helium flow on one of the two current leads, which electrically connects the coil at 4.5 K to the busbars at room temperature. With no helium flow on the lead, the voltage drop and the temperatures across the leads increase up to the defined thresholds, triggering a fast dump through the Magnet Safety System (MSS). The automatic reaction triggered by the MSS worked properly. The helium release was limited as the pressure rise was just at the limit of the safety valve opening pressure. The average temperature of the magnet reached 72 K. It took four days to recover the temperature and refill the helium volumes. The faulty valve controller was replaced by a spare one before the magnet ramp-up resumed....

  5. Quality of life after total colectomy with ileorectal anastomosis or proctocolectomy and ileal pouch-anal anastomosis for familial adenomatous polyposis

    NARCIS (Netherlands)

    van Duijvendijk, P.; Slors, J. F.; Taat, C. W.; Oosterveld, P.; Sprangers, M. A.; Obertop, H.; Vasen, H. F.

    2000-01-01

    BACKGROUND: Knowledge of postoperative health status is important in decision-making about the type of operation necessary in patients with familial adenomatous polyposis (FAP). This study compared the quality of life (QoL) between patients with an ileorectal anastomosis (group 1) and those with an

  6. Blunt penetration technique for treatment of a completely obstructed anastomosis after rectal resection: a case report.

    Science.gov (United States)

    Yazawa, Keiichi; Morioka, Daisuke; Matsumoto, Chizuru; Miura, Yasuhiko; Togo, Shinji

    2014-06-27

    We present a case of completely obstructed anastomosis after rectal resection which was nonsurgically and successfully treated with a blunt penetration technique using a commonly used device for transanal ileus drainage. The technique we used in this case has not been previously reported. A 79-year-old Japanese man underwent redo rectal resection for completely separated anastomosis which was caused by anastomotic leakage after a sigmoidectomy performed 3 years previously that was remedied by diverging ileostomy. Immediately after the redo surgery, fluoroscopy showed good passage through the colorectal anastomosis but no anastomotic leakage. However, fluoroscopy and colonoscopy prior to the ileostomy takedown showed complete obstruction of the anastomosis. Unlike usual anastomotic strictures, the lumen between colon oral and rectum anal to the anastomosis was completely discontinued by a membranous structure. Therefore, a conventional balloon dilatation technique was unsuitable for this condition. We applied a blunt penetration technique using a commercially available device designed as a transanal drainage system for obstructing colorectal cancer to restore the continuity between the colon oral and rectum anal to the anastomosis. After restoring the continuity, we performed conventional balloon dilatation for the anastomosis and successfully treated the anastomotic obstruction. Subsequently, the patient underwent ileostomy takedown and is currently doing well 12 months after the ileostomy takedown. The penetration technique we applied is easy and less stressful to adopt because it does not require usage of materials specialized for other particular purposes. Furthermore, we believe that this technique is superior in safety to other reported methods for this condition even if applied in the wrong direction because this technique does not utilize electrocision or sharp needle puncture.

  7. Stapled versus hand-sewn cervical esophagogastric anastomosis in patients undergoing esophagectomy: A Retrospective Cohort Study

    Science.gov (United States)

    Mishra, Pramod Kumar; Shah, Harsh; Gupta, Nikhil; Varshney, Vaibhav; Patil, Nilesh Sadashiv; Jain, Amit; Saluja, Sundeep Singh

    2016-01-01

    Introduction Anastomotic leak is one of the main causes of morbidity following esophageal resection for carcinoma of the esophagus and gastroesophageal junction. We compared hand sewn and stapled cervical esophagogastric anastomotic techniques in terms of postoperative complications. Methods All patients who underwent esophagectomy with cervical esophagogastric anastomosis at a single academic center from 2004 to 2014 were included in the study. Both early and late complications were analyzed. Results 153 patients underwent resection for carcinoma of the esophagus and gastroesophageal junction. Of these 140 patients had esophagectomy with cervical esophagogastric anastomosis. 66 patients underwent a hand sewn anastomosis and 74 patients had a side-to-side stapled anastomosis fashioned. Both groups were comparable with respect to preoperative characteristics. There was no difference in the operative blood loss and T and N stage of the disease. The overall morbidity and mortality was 32.8% and 6.4%, respectively. Overall leak rate was 17%. There was no difference in the leak rates among two groups (12 in the hand-sewn group & 12 in the Stapled stapled group; p = 0.82). The rate of anastomotic stricture was significantly higher for the hand sewn group (16.1% vs 4.3%; p = 0.03) at median follow up of 30 months. Conclusion Both hand sewn and stapled anastomotic techniques are equally effective way of performing a cervical esophagogastric anastomosis. However, patients having anastomotic leak develop anastomotic stricture more often in those having hand-sewn anastomosis compared to stapled anastomosis. PMID:27222711

  8. Impact of top end anastomosis design on patency and flow stability in coronary artery bypass grafting.

    Science.gov (United States)

    Koyama, Sachi; Kitamura, Tadashi; Itatani, Keiichi; Yamamoto, Tadashi; Miyazaki, Shohei; Oka, Norihiko; Nakashima, Kouki; Horai, Tetsuya; Ono, Minoru; Miyaji, Kagami

    2016-05-01

    For coronary artery bypass grafting (CABG), free grafts such as a saphenous vein or radial artery are often used for grafts to the lateral and posterior walls. However, the relationship between top-end anastomosis design and long-term patency remains unknown. Because coronary artery blood flow is dominant during diastole, top-end anastomosis may work better if the graft is directed towards the apex, whereas the shortest graft pathway appears to be most efficient. Using computational fluid dynamic models, we evaluated the hemodynamic variables that were affected by the angle of the top-end anastomosis. We created three-dimensional geometries of the aortic root with coronary arteries that involved 75 % stenosis in the obtuse marginal and postero-lateral branches. Two bypass models under vasodilator administration were created: in a"Model A", the top-end anastomosis is parallel to the long axis of the ascending aorta and the graft passed over the conus directed towards the apex; in a "Model B", the top-end anastomosis is directed toward the shortest pathway, and form near the right angles to the long axis of the ascending aorta. Wall shear stress (WSS) and its fluctuation, an oscillatory shear index (OSI) were evaluated to predict fibrosis progression at the anastomosis site and graft flow. Graft flow was 197.3 ml/min and 207.3 ml/min in the "Model A" and "Model B", respectively. The minimal WSS value inside the graft with the "Model A" and "Model B" was 0.53 Pa and 4.09 Pa, respectively, and the OSI value was 0.46 and 0.04, respectively. The top-end anastomosis of a free graft should be directed vertically towards the aorta to achieve the shortest graft pathway to maintain a high graft flow rate and to avoid the risks of endothelial fibrosis and plaque progression over the long-term after CABG.

  9. Body composition changes after totally laparoscopic distal gastrectomy with delta-shaped anastomosis: a comparison with conventional Billroth I anastomosis.

    Science.gov (United States)

    Park, Ki Bum; Kwon, Oh Kyoung; Yu, Wansik; Jang, Byeong-Churl

    2016-10-01

    The purpose of this study was to compare body composition changes of patients undergoing totally laparoscopic distal gastrectomy (TLDG) with delta-shaped anastomosis (DSA) versus conventional laparoscopic distal gastrectomy (CLDG). Data from gastric cancer patients who underwent laparoscopic distal gastrectomy for histologically proven gastric cancer in KNUMC from January 2013 to May 2014 were collected and reviewed. We examined 85 consecutive patients undergoing TLDG or CLDG: 41 patients underwent TLDG and 44 patients underwent CLDG. Body composition was assessed by segmental multifrequency bioelectrical impedance analysis. We compared the changes in nutritional parameters and body composition from preoperative status between the two groups at postoperative 6 and 12 months. All of the postoperative changes in the body composition and nutritional indices were similar between the two groups with the exception of visceral fat areas (VFAs) and albumin levels. VFAs increased at 6 months postoperatively in the TLDG group and a significant difference was shown at 12 months postoperatively between the TLDG and CLDG groups (86.7 ± 22.8 and 74.7 ± 21.9 cm(2), respectively, P body composition seemed comparable to those of CLDG. Six months postoperatively, VFAs and albumin levels were recovered in the TLDG group but not in the CLDG group. Thus, TLDG seems to be a novel surgical method.

  10. The effect of disc-shaped gastric resection of anastomosis site on reducing postoperative dysphagia and stricture after esophagogastric anastomosis in patients with esophageal cancer.

    Science.gov (United States)

    Mahmodlou, Rahim; Shateri, Kamran; Homayooni, Faramarz; Hatami, Sanaz

    2017-02-01

    Esophagectomy remains the most reliable technique for managing esophageal cancer, but anastomotic complications including postoperative leak, ischemia and stricture negatively affect outcomes of this specific surgery. The aim of this study was to evaluate the effects of a novel method of esophagogastric anastomosis for reducing postoperative dysphagia and stricture formation. Eighty patients who were scheduled for esophagectomy due to esophageal cancer were randomly assigned into two groups: intervention and control (40 each). In the control group, the esophagogastric anastomosis was performed with a linear gastric incision, whilst in the intervention group a new method of disc-shaped gastric resection for anastomosis was applied. Postoperative outcomes were compared between the two groups. The incidence of postoperative dysphagia and anastomotic stricture was significantly lower in the disc-shaped resection group (dysphagia 45% vs 75%, P = 0.02; stricture 12.5% vs 32.5%, P = 0.03), whilst the length of stay in an intensive care unit (ICU), anastomotic leakage and other complications were not significantly different between the two groups (all P > 0.05). Anastomotic complications can be reduced by improving surgical techniques. The decreased incidence of postoperative dysphagia and anastomotic stricture in our study may be partly due to providing the proper diameter for the site of anastomosis when using the disc-shaped gastric resection method. Hence, this new method can improve the clinical outcomes of patients who undergo esophagectomy with esophagogastric anastomosis. © The Author(s) 2016. Published by Oxford University Press and Sixth Affiliated Hospital of Sun Yat-Sen University.

  11. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet worked very well at 3.8 T as expected, despite a technical issue that manifested twice in the cryogenics since June. All the other magnet sub-systems worked without flaw. The issue in the cryogenics was with the cold box: it could be observed that the cold box was getting progressively blocked, due to some residual humidity and air accumulating in the first thermal exchanger and in the adsorber at 65 K. This was later confirmed by the analysis during the regeneration phases. An increase in the temperature difference between the helium inlet and outlet across the heat exchanger and a pressure drop increase on the filter of the adsorber were observed. The consequence was a reduction of the helium flow, first compensated by the automatic opening of the regulation valves. But once they were fully opened, the flow and refrigeration power reduced as a consequence. In such a situation, the liquid helium level in the helium Dewar decreased, eventually causing a ramp down of the magnet current and a field...

  12. MAGNET

    CERN Multimedia

    B. Curé

    MAGNET During the winter shutdown, the magnet subsystems went through a full maintenance. The magnet was successfully warmed up to room temperature beginning of December 2008. The vacuum was broken later on by injecting nitrogen at a pressure just above one atmosphere inside the vacuum tank. This was necessary both to prevent any accidental humidity ingress, and to allow for a modification of the vacuum gauges on the vacuum tank and maintenance of the diffusion pumps. The vacuum gauges had to be changed, because of erratic variations on the measurements, causing spurious alarms. The new type of vacuum gauges has been used in similar conditions on the other LHC experiments and without problems. They are shielded against the stray field. The lubricants of the primary and diffusion pumps have been changed. Several minor modifications were also carried out on the equipment in the service cavern, with the aim to ease the maintenance and to allow possible intervention during operation. Spare sensors have been bough...

  13. MAGNET

    CERN Multimedia

    Benoit Curé.

    The magnet operation restarted end of June this year. Quick routine checks of the magnet sub-systems were performed at low current before starting the ramps up to higher field. It appeared clearly that the end of the field ramp down to zero was too long to be compatible with the detector commissioning and operations plans. It was decided to perform an upgrade to keep the ramp down from 3.8T to zero within 4 hours. On July 10th, when a field of 1.5T was reached, small movements were observed in the forward region support table and it was decided to fix this problem before going to higher field. At the end of July the ramps could be resumed. On July 28th, the field was at 3.8T and the summer CRAFT exercise could start. This run in August went smoothly until a general CERN wide power cut took place on August 3rd, due to an insulation fault on the high voltage network outside point 5. It affected the magnet powering electrical circuit, as it caused the opening of the main circuit breakers, resulting in a fast du...

  14. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

    The magnet is fully stopped and at room temperature. The maintenance works and consolidation activities on the magnet sub-systems are progressing. To consolidate the cryogenic installation, two redundant helium compressors will be installed as ‘hot spares’, to avoid the risk of a magnet downtime in case of a major failure of a compressor unit during operation. The screw compressors, their motors, the mechanical couplings and the concrete blocks are already available and stored at P5. The metallic structure used to access the existing compressors in SH5 will be modified to allow the installation of the two redundant ones. The plan is to finish the installation and commissioning of the hot spare compressors before the summer 2014. In the meantime, a bypass on the high-pressure helium piping will be installed for the connection of a helium drier unit later during the Long Shutdown 1, keeping this installation out of the schedule critical path. A proposal is now being prepared for the con...

  15. Tokamak plasma variations under rapid compression

    International Nuclear Information System (INIS)

    Holmes, J.A.; Peng, Y.K.M.; Lynch, S.J.

    1980-04-01

    Changes in plasmas undergoing large, rapid compressions are examined numerically over the following range of aspect ratios A:3 greater than or equal to A greater than or equal to 1.5 for major radius compressions of circular, elliptical, and D-shaped cross sections; and 3 less than or equal to A less than or equal to 6 for minor radius compressions of circular and D-shaped cross sections. The numerical approach combines the computation of fixed boundary MHD equilibria with single-fluid, flux-surface-averaged energy balance, particle balance, and magnetic flux diffusion equations. It is found that the dependences of plasma current I/sub p/ and poloidal beta anti β/sub p/ on the compression ratio C differ significantly in major radius compressions from those proposed by Furth and Yoshikawa. The present interpretation is that compression to small A dramatically increases the plasma current, which lowers anti β/sub p/ and makes the plasma more paramagnetic. Despite large values of toroidal beta anti β/sub T/ (greater than or equal to 30% with q/sub axis/ approx. = 1, q/sub edge/ approx. = 3), this tends to concentrate more toroidal flux near the magnetic axis, which means that a reduced minor radius is required to preserve the continuity of the toroidal flux function F at the plasma edge. Minor radius compressions to large aspect ratio agree well with the Furth-Yoshikawa scaling laws

  16. Compression experiments on the TOSKA tokamak

    International Nuclear Information System (INIS)

    Cima, G.; McGuire, K.M.; Robinson, D.C.; Wootton, A.J.

    1980-10-01

    Results from minor radius compression experiments on a tokamak plasma in TOSCA are reported. The compression is achieved by increasing the toroidal field up to twice its initial value in 200μs. Measurements show that particles and magnetic flux are conserved. When the initial energy confinement time is comparable with the compression time, energy gains are greater than for an adiabatic change of state. The total beta value increases. Central beta values approximately 3% are measured when a small major radius compression is superimposed on a minor radius compression. Magnetic field fluctuations are affected: both the amplitude and period decrease. Starting from low energy confinement times, approximately 200μs, increases in confinement times up to approximately 1 ms are measured. The increase in plasma energy results from a large reduction in the power losses during the compression. When the initial energy confinement time is much longer than the compression time, the parameter changes are those expected for an adiabatic change of state. (author)

  17. The effects of duration of CO2 pneumoperitoneum on colonic anastomosis.

    Science.gov (United States)

    Ozer, Ilter; Ulas, Murat; Ercan, Metin; Ozogul, Yusuf B; Zengin, Neslihan; Bostanci, E Birol; Ozel, Ummuhani; Bilgihan, Ayse; Akoglu, Musa

    2008-01-01

    The aim of this study is to evaluate the effects of duration of carbon dioxide (CO(2)) pneumoperitoneum on experimental colonic anastomosis. Forty-eight male Sprague-Dawley rats were used. The rats were divided into three groups. The rats in group 1 (n = 16) underwent laparotomy and colonic anastomosis without pneumoperitoneum. The rats in group 2 (n = 16) and group 3 (n = 16) were subjected to 2 and 4 hours of 12 mm Hg pneumoperitoneum, respectively, before laparotomy and colonic anastomosis. Half of the rats were sacrified on the third postoperative day; and the other half, on the seventh postoperative day. A colonic segment including anastomosis site was resected for histopathologic and biochemical evaluation. On day 3, hydroxyproline levels of the three groups were similar. The edema score of group 2 was significantly higher than that of group 1, and the necrosis score was higher in group 2 than in group 3. The scores of the other histopathologic parameters were similar. On day 7, group 3 showed significantly higher hydroxyproline levels than group 1, and group 1 showed a higher necrosis score than group 3. In conclusion, CO(2) pneumoperitoneum of 12 mm Hg for 2 and 4 hours did not result in impaired healing of experimental colonic anastomosis.

  18. The fate of suboptimal anastomosis after colon resection: An experimental study.

    Science.gov (United States)

    Yıldız, Mehmet Kamil; Okan, İsmail; Nazik, Hasan; Bas, Gurhan; Alimoglu, Orhan; İlktac, Mehmet; Daldal, Emin; Sahin, Mustafa; Kuvat, Nuray; Ongen, Betugul

    2014-11-01

    The fate of suboptimal anastomosis is unknown and early detection of anastomotic leakage after colon resection is crucial for the proper management of patients. Twenty-six rats were assigned to "Control", "Leakage" and "Suboptimal anastomosis" groups where they underwent either sham laparotomy, cecal ligation, and puncture or anastomosis with four sutures following colon resection, respectively. At the fifth hour and on the third and ninth days; peripheral blood and peritoneal washing samples through relaparotomy were obtained. The abdomen was inspected macroscopically for anastomotic healing. Polymerase chain reaction (PCR) with 16s rRNA and E.coli-specific primers were run on all samples along with aerobic and anaerobic cultures. The sensitivity and specificity of PCR on different bodily fluids with 16s rRNA and E.coli-specific primers were 100% and 78%, respectively. All samples of peritoneal washing fluids on the third and ninth days showed presence of bacteria in both PCR and culture. The inspection of the abdomen revealed signs of anastomotic leakage in eight rats (80%), whereas mortality related with anastomosis was detected in two (20%). Anastomotic leakage with suboptimal anastomosis after colon resection is high and the early detection is possible by running PCR on peritoneal samples as early as 72 hours.

  19. [Surgical management of postoperative stricture of anastomosis after operation of intersphincteric resection for lower rectal cancer].

    Science.gov (United States)

    Yi, Bing-qiang; Wang, Zhen-jun; Zhao, Bo; Wei, Guang-hui; Han, Jia-gang; Ma, Hua-chong; Zhao, Bao-cheng

    2013-07-01

    To study surgical treatment of postoperative stricture of anastomosis for lower rectal cancer. The data of 9 cases who were diagnosed as postoperative stricture of anastomosis after operation of intersphincteric resection for lower rectal cancer during January 2008 to June 2011 were analyzed retrospectively. Transanal excision of stricture were used in 3 cases diagnosed as membranous stricture. Transanal radial incision of stricture were used in 5 cases diagnosed as tubulous stricture. Biologic patch was used to repair the defect of the posterior wall of rectum after excision of severe stricture in 1 case. All 9 cases of postoperative stricture of anastomosis were cured by surgery. Anal dilation were performed every day by patients themselves after discharge. Digital examination showed that 1 to 2 fingers could pass through the anastomosis after operation. The patient whose rectal defect was repaired by biological patch underwent colonoscopy examination two weeks after operation. Colonoscopy showed that the biological patch had been filled with granulation and integrated into the surrounding intestinal tissue. All patients defecated without difficulty and the anal function of all patients was good after restoration of intestinal continuity. Aggressive surgery, combining with the use of biological patch if necessary is an effective therapy of postoperative stricture of anastomosis for lower rectal cancer.

  20. Mucociliary clearance following tracheal resection and end-to-end anastomosis.

    Science.gov (United States)

    Toomes, H; Linder, A

    1989-10-01

    Mucociliary clearance is an important cleaning system of the bronchial tree. The complex transport system reacts sensitively to medicinal stimuli and inhaled substances. A disturbance causes secretion retention which encourages the development of acute and chronic pulmonary diseases. It is not yet known in which way sectional resection of the central airway effects mucociliary clearance. A large number of the surgical failures are attributable to septic complications in the area of the anastomosis. In order to study the transportation process over the anastomosis, ten dogs underwent a tracheal resection with end-to-end anastomosis, and the mucociliary activity was recorded using a bronchoscopic video-technical method. Recommencement of mucous transport was observed on the third, and transport over the anastomosis from the sixth to tenth, postoperative days. The mucociliary clearance had completely recovered on the twenty-first day in the majority of dogs. Histological examination of the anastomoses nine months postoperatively showed a flat substitute epithelium without cilia-bearing cells in all dogs. This contrasts with the quick restitution of the transport function. In case of undamaged respiratory mucosa, a good adaptation of the resection margins suffices for the mucous film to slide over the anastomosis.

  1. Comparison of laparoscopic and conventional surgery of intestinal anastomosis in dogs

    Directory of Open Access Journals (Sweden)

    O. J. Ali

    2008-01-01

    Full Text Available The aim of this study was to evaluate operative laparoscopy in comparison with conventional laparotomy for intestinal resection and anastomosis in dogs. Eighteen adult dogs were equally and randomly divided into 3 groups: Group I: Intestinal anastomosis was performed extracorporeally, by laparoscopic-assisted surgery, in which a 5cm loop of small bowel was exteriorized through a mini-laparotomy opening (an enlarged trocar incision 1.5-2 cm in length, then surgically resected and anastomosed by simple interrupted suture 3-0 polygalactine. Group II: Underwent laparoscopic intracorporeal intestinal resection and anastomosis, in which the loop of the small bowel was suspended into the ventral abdominal wall, then it was resected and anastomsed with simple continuous suture by polygalactine 3-0. Group III: Small bowel resection and anastomosis was conducted by conventional laparotomy technique with simple interrupted pattern by polygalactine 3-0 suture. The result showed that laparoscopic intestinal resection and anastomosis by either intra- or extracorporeal techniques can be applied in dogs safely and have less morbidity rate. Intra abdominal adhesion of the omentum and even the bowel to the abdominal wall occurred in group III but not in groups I and II. The post operative hospitalization time was earlier in group I and II, as indicated by the earlier return of intestinal motility and appetite, in comparison to group III where it was delayed.

  2. EARLY AND LATE COMPLICATIONS AMONG LONG-TERM COLORECTAL CANCER SURVIVORS WITH OSTOMY OR ANASTOMOSIS

    Science.gov (United States)

    Liu, Liyan; Herrinton, Lisa J.; Hornbrook, Mark C.; Wendel, Christopher S.; Grant, Marcia; Krouse, Robert S.

    2012-01-01

    Purpose Among long-term (≥5 years) colorectal cancer survivors with permanent ostomy or anastomosis, we compared the incidence of medical and surgical complications and examined the relationship of complications with health-related quality of life. Background The incidence and effects of complications on long-term health-related quality of life among colorectal cancer survivors are not adequately understood. Methods Participants (284 ostomy/395 anastomosis) were long-term colorectal cancer survivors enrolled in an integrated health plan. Health-related quality of life was assessed via mailed survey questionnaire in 2002–2005. Information on colorectal cancer, surgery, co-morbidities, and complications was obtained from computerized data and analyzed using survival analysis and logistic regression. Results Ostomy and anastomosis survivors were followed an average 12.1 and 11.2 years, respectively. Within 30 days of surgery, 19% of ostomy and 10% of anastomosis survivors experienced complications (pOstomy was associated with long-term fistula (odds ratio 5.4; 95% CI 1.4–21.2), and among ostomy survivors, fistula was associated with reduced health-related quality of life (postomy have more complications early in their survivorship period, but complications among anastomosis survivors catch up after 20 years, when the two groups have convergent complication rates. Among colorectal cancer survivors with ostomy, fistula has especially important implications for health-related quality of life. PMID:20087096

  3. The side-to-side fashion for individual distal coronary anastomosis using venous conduit.

    Science.gov (United States)

    Kato, Takayoshi; Tsunekawa, Tomohiro; Motoji, Yusuke; Hirakawa, Akihiro; Okawa, Yasuhide; Tomita, Shinji

    2017-04-01

    Regarding to coronary artery bypass grafting (CABG), the end-to-side anastomosis (ESA) has been performed as a gold standard. Recently, the effectiveness of the distal side-to-side anastomosis (SSA) in CABG using internal mammary artery has been reported. The benefit of SSA comparing to ESA also has been disclosed by computing simulation. However, use of SSA by venous conduit for individual CABG has not been reported. In this study, we investigated feasibility of SSA. From January 2013 to October 2014, we conducted 114 CABGs. There were 92 venous distal anastomoses without sequential anastomotic site (61 SSA and 31 ESA). The anastomosis was evaluated before discharge and at 1 year after the procedure by angiography or multi-detector row computed tomographic coronary angiography. The median values for time to anastomosis were 13 min in the two group (p = 0.89). There was no revision of anastomosis in both groups. Additional stitches for hemostasis were required significantly less in SSA than ESA (18.0 vs 45.2 %, respectively, p fashion is easy to perform and maybe beneficial in blood flow pattern.

  4. Results of subscale MTF compression experiments

    Science.gov (United States)

    Howard, Stephen; Mossman, A.; Donaldson, M.; Fusion Team, General

    2016-10-01

    In magnetized target fusion (MTF) a magnetized plasma torus is compressed in a time shorter than its own energy confinement time, thereby heating to fusion conditions. Understanding plasma behavior and scaling laws is needed to advance toward a reactor-scale demonstration. General Fusion is conducting a sequence of subscale experiments of compact toroid (CT) plasmas being compressed by chemically driven implosion of an aluminum liner, providing data on several key questions. CT plasmas are formed by a coaxial Marshall gun, with magnetic fields supported by internal plasma currents and eddy currents in the wall. Configurations that have been compressed so far include decaying and sustained spheromaks and an ST that is formed into a pre-existing toroidal field. Diagnostics measure B, ne, visible and x-ray emission, Ti and Te. Before compression the CT has an energy of 10kJ magnetic, 1 kJ thermal, with Te of 100 - 200 eV, ne 5x1020 m-3. Plasma was stable during a compression factor R0/R >3 on best shots. A reactor scale demonstration would require 10x higher initial B and ne but similar Te. Liner improvements have minimized ripple, tearing and ejection of micro-debris. Plasma facing surfaces have included plasma-sprayed tungsten, bare Cu and Al, and gettering with Ti and Li.

  5. Benign compression fractures of the spine: signal patterns

    International Nuclear Information System (INIS)

    Ryu, Kyung Nam; Choi, Woo Suk; Lee, Sun Wha; Lim, Jae Hoon

    1992-01-01

    Fifteen patients with 38 compression fractures of the spine underwent magnetic resonance(MR) imaging. We retrospectively evaluated MR images in those benign compression fractures. MR images showed four patterns in T1-weighted images. MR imaging patterns were normal signal(21), band like low signal(8), low signal with preservation of peripheral portion of the body(8), and diffuse low signal through the vertebral body(1). The low signal portions were changed to high signal intensities in T2-weighted images. In 7 of 15 patients (11 compression fractures), there was a history of trauma, and the remaining 8 patients (27 compression fractures) had no history of trauma. Benign compression fractures of trauma, remained 8 patients (27 compression fractures) were non-traumatic. Benign compression fractures of the spine reveal variable signal intensities in MR imagings. These patterns of benign compression fractures may be useful in interpretation of MR imagings of the spine

  6. MAGNET

    CERN Multimedia

    Benoit Curé

    The magnet subsystems resumed operation early this spring. The vacuum pumping was restarted mid March, and the cryogenic power plant was restarted on March 30th. Three and a half weeks later, the magnet was at 4.5 K. The vacuum pumping system is performing well. One of the newly installed vacuum gauges had to be replaced at the end of the cool-down phase, as the values indicated were not coherent with the other pressure measurements. The correction had to be implemented quickly to be sure no helium leak could be at the origin of this anomaly. The pressure measurements have been stable and coherent since the change. The cryogenics worked well, and the cool-down went quite smoothly, without any particular difficulty. The automated start of the turbines had to be fine-tuned to get a smooth transition, as it was observed that the cooling power delivered by the turbines was slightly higher than needed, causing the cold box to stop automatically. This had no consequence as the cold box safety system acts to keep ...

  7. MAGNET

    CERN Multimedia

    B. Curé

    During the winter shutdown, the magnet subsystems went through a full maintenance. The magnet was successfully warmed up to room temperature beginning of December 2008. The vacuum was broken later on by injecting nitrogen at a pressure just above one atmosphere inside the vacuum tank. This was necessary both to prevent any accidental humidity ingress, and to allow for a modification of the vacuum gauges on the vacuum tank and maintenance of the diffusion pumps. The vacuum gauges had to be changed, because of erratic variations on the measurements, causing spurious alarms. The new type of vacuum gauges has been used in similar conditions on the other LHC experiments and without problems. They are shielded against the stray field. The lubricants of the primary and diffusion pumps have been changed. Several minor modifications were also carried out on the equipment in the service cavern, with the aim to ease the maintenance and to allow possible intervention during operation. Spare sensors have been bought. Th...

  8. Circular myotomy as an aid to resection and end-to-end anastomosis of the esophagus.

    Science.gov (United States)

    Attum, A A; Hankins, J R; Ngangana, J; McLaughlin, J S

    1979-08-01

    Segments ranging from 40 to 70% of the thoracic esophagus were resected in 80 mongrel dogs. End-to-end anastomosis was effected after circular myotomy either proximal or distal, or both proximal and distal, to the anastomosis. Among dogs undergoing resection of 60% of the esophagus, distal myotomy enabled 6 of 8 animals to survive, and combined proximal and distal myotomy permitted 8 of 10 to survive. Cineesophagography was performed in a majority of the 50 surviving animals and showed no appreciable delay of peristalsis at the myotomy sites. When these sites were examined at postmortem examination up to 13 months after operation, 1 dog showed a small diverticulum but none showed dilatation or stricture. It is concluded that circular myotomy holds real promise as a means of extending the clinical application of esophageal resection with end-to-end anastomosis.

  9. Pouch failures following ileal pouch-anal anastomosis for ulcerative colitis

    DEFF Research Database (Denmark)

    Mark-Christensen, A; Erichsen, R; Brandsborg, S

    2018-01-01

    BACKGROUND: The ileal pouch-anal anastomosis is a procedure offered to patients with ulcerative colitis who opt for restoration of bowel continuity. The aim of this study was to determine the risk of pouch failure and ascertain risk factors associated with failure. METHOD: 1,991 patients with ulc......BACKGROUND: The ileal pouch-anal anastomosis is a procedure offered to patients with ulcerative colitis who opt for restoration of bowel continuity. The aim of this study was to determine the risk of pouch failure and ascertain risk factors associated with failure. METHOD: 1,991 patients......-anal anastomosis from Denmark, where pouch surgery is centralized, females had a higher risk of pouch failure. Of modifiable factors, low hospital volume and non-diversion were associated with a higher risk of pouch failure. This article is protected by copyright. All rights reserved....

  10. Performance of the 10kV, 100-kA pulsed-power modules for the FRX-C magnetic compression experiment

    International Nuclear Information System (INIS)

    Rej, D.J.; Waganaar, W.J.

    1989-01-01

    In this paper, we present detailed performance data collected from over a year's operation of the 25 and 50-kJoule pulsed-power capacitor-bank modules developed for the Los Alamos magnetic fusion facility FRX-C. These modules supply the 5-MA magnet current needed for the compressional heating of compact toroid plasmoids. To date, 54 modules have been built and successfully tested at their full design rating: 100-kA peak output current at 10-kV charge, τ 1/4 = 60 μs (25-kJ module), or 110 μs (50-kJ module), crowbar L/R ≤ 1 ms. Modules are compact, cost about $5000 each, and though designed for 25 or 50 kJ, they can be easily modified for other pulsed-power applications. Energy is stored in 25-kJ capacitors. Start and crowbar switching is performed with a pair of water-cooled, size-D ignitrons. As an alternative to an ignitron, crowbar switching by solid-state rectifiers has been successfully demonstrated. Current is conducted between components and to the load by parallel-plate transmission lines and by a parallel array of commercially-available coaxial cable. 4 refs., 8 figs

  11. Flux compression generators as plasma compression power sources

    International Nuclear Information System (INIS)

    Fowler, C.M.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.; Thomson, D.B.; Garn, W.B.

    1979-01-01

    A survey is made of applications where explosive-driven magnetic flux compression generators have been or can be used to directly power devices that produce dense plasmas. Representative examples are discussed that are specific to the theta pinch, the plasma gun, the dense plasma focus and the Z pinch. These examples are used to illustrate the high energy and power capabilities of explosive generators. An application employing a rocket-borne, generator-powered plasma gun emphasizes the size and weight potential of flux compression power supplies. Recent results from a local effort to drive a dense plasma focus are provided. Imploding liners ae discussed in the context of both the theta and Z pinches

  12. COMPARATIVE ANALYSIS OF PRIMARY REPAIR VERSUS RESECTION AND ANASTOMOSIS IN JEJUNOILEAL PERFORATIONS IN SOUTHERN ODISHA

    Directory of Open Access Journals (Sweden)

    Charan Panda

    2017-11-01

    Full Text Available BACKGROUND Small intestinal perforation remains a major issue in this region of study. Most often, it is caused by either infections due to typhoid, tuberculosis or traumatic due to blunt or penetrating injuries. The mortality reported is related to various factors including age, delayed treatment, sepsis at presentation and inadequate treatment due to lack of resources. Management is therefore complex not only with regards to choose the most suitable surgical treatment, but also as regards an early diagnosis of complications, which is difficult in absence of diagnostic modalities that are often not available. The aim of the study is to compare primary repair versus intestinal resection and anastomosis in case of jejunoileal perforations due to various aetiologies. MATERIALS AND METHODS 60 patients with acute peritonitis underwent emergency laparotomy. Aetiology, number of perforations, size of perforations, site of perforations, surgical procedure undertaken and postoperative complications were recorded. The patients were divided into two groups according to the surgical procedure adapted at laparotomy; primary repair and intestinal resection and anastomosis. Clinical data, intraoperative findings and complications were evaluated and compared. RESULTS 40 out of 60, we found jejunoileal perforations, gastroduodenal in 20 patients. 23 had undergone primary repair and 17 resection and anastomosis. Postoperative complications were compared among both groups in relation to various factors. Conclusion was drawn as to prefer, which surgery in which group of patients. CONCLUSION In our study, detailed analysis of the complication pattern shows primary closure is associated with less number of complications in traumatic cases and resection and anastomosis is associated with lesser complications in infective cases. Primary closure is less complicated for single perforations as compared to multiple perforations. Resection and anastomosis is less

  13. Fluorescent Angiography Used to Evaluate the Perfusion Status of Anastomosis in Laparoscopic Anterior Resection.

    Science.gov (United States)

    Koh, Frederick H; Tan, Ker-Kan

    2016-12-01

    Anastomotic leakage after gastrointestinal surgery is associated with significant morbidity and mortality.1 Insufficient vascular supply is one cause.2 Recent reports of using intraoperative indocyanine green (ICG) fluorescent angiography to evaluate whether perfusion of the anastomosis is adequate has yielded positive outcomes.3 - 6 The authors describe their use of ICG-enhanced fluorescence angiography in a laparoscopic anterior resection. The patient was an 80-year-old with an upper rectal adenocarcinoma and significant cardiovascular risk factors. Fluorescence angiography with 0.4 mg/kg of ICG was administered intravenously just before the colorectal anastomosis was fashioned. A near-infrared (NIR) laparoscopic camera (KARLSTORZ, GmbH & Co. KG, Tuttlingen, Germany) was used to inspect the anastomosis. For this video, 0.4 mg/kg of ICG also was injected after ligation of the inferior mesenteric artery to demonstrate the appearance of a poorly perfused sigmoid bowel. Just before the staple was fired to fashion the colorectal anastomosis, an intravenous bolus of ICG was administered. Within seconds, vessels on both ends of the anastomosis turned fluorescent blue, indicating adequacy of perfusion. The use of ICG did not significantly lengthen the operative time (285 min) because its effect appeared within seconds after its administration. The patient recovered well and was discharged on postoperative day 5. Another four patients who also underwent intraoperative fluorescent angiography for left-sided colorectal lesions did not experience anastomotic leakage. The study showed that ICG fluorescent angiography is a simple and quick intraoperative tool for evaluating the perfusion of the anastomosis. The authors' experience with ICG fluorescent angiography has shown promising results, with a 0 % anastomotic leak rate.

  14. The use of arteriovenous anastomosis for venous drainage during Tamai zone I fingertip replantation.

    Science.gov (United States)

    Wu, Fei; Shen, Xiaofang; Eberlin, Kyle R; Sun, Zhibo; Zhou, Xiao; Xue, Mingyu

    2018-03-27

    The purpose of this study was to evaluate outcomes for patients sustaining a distal fingertip amputation who underwent replantation witharteriovenous anastomosis for venous drainage over a one year period at our institution. This technique has been utilized when insufficient veins are identified in the amputated part for standard veno-venous anastomosis. A retrospective study was performed on patients presenting from 2013 to 2014. Guillotine, crush, and avulsion/degloving injuries were included if they underwent fingertip (Tamai Zone I) replantation with arterial anastomosis for vascular inflow and arteriovenous anastomosis for venous drainage. The cases were further classified as Ishikawa subzone I and subzone II. Arteriovenous anastomosis for venous drainage during replantation was used in 45 digits in 35 patients. 41 of the 45 digits underwent successful replantation using this technique (91%). The mean active ROM in the DIP joint of the fingers and in the IP joint of thumbs was 65° and 57°, respectively. Sensory evaluation demonstrated a mean of 6.9 mm s2PD in digits where the digital nerves could be repaired. 11 replanted digits without nerve repair regained some sensory recovery with a mean of 9.6 mm s2PD. 91% of patients were highly satisfied with the appearance of the replanted digits based on Tamai criteria. Arteriovenous anastomosis for venous outflow should be considered during zone I fingertip replantation if sufficient veins are not identified in the amputated part. This technique may allow for more routine and successful distal replantation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Fingertip amputation salvage on arterial anastomosis alone: an investigation of its limitations.

    Science.gov (United States)

    Ito, Hiroshi; Sasaki, Kenji; Morioka, Kousuke; Nozaki, Motohiro

    2010-09-01

    We have previously reported the importance of adequate and precise arterial anastomosis and the hypothesis that, up to subzone III, fingertip amputation salvage can be achieved on arterial anastomosis alone. These findings were reported during the meeting of the Japanese Society of Reconstructive Microsurgery. This is our follow-up report with insight and opinion on the limitations of complete fingertip amputation salvage on arterial anastomosis alone. We examined 67 fingers (59 patients) with fingertip amputations presenting to our hospital between January 2005 and December 2008. Amputation levels and whether these injuries received only arterial or both arterial and venous anastomoses were noted. Fisher exact test was used to examine statistical differences between the groups. Amputation levels were 11 in subzone I, 20 in subzone II, 17 in subzone III, and 19 in subzone IV. Successful replantation was achieved in 87% (58 of 67) of fingers. There was no statistically significant difference between fingers receiving arterial alone versus both anastomoses in amputations of subzones I, II, and III. We found that with proper postoperative congestion care, no statistically significant difference in replantation success of fingers receiving arterial anastomosis alone versus both arterial and venous were noted up to subzone III. However, in subzone IV, regardless of the postoperative congestion, compete necrosis rates are high; thus, it is speculated that a venous anastomosis is necessary for successful replantation. It is preferable to perform as many anastomoses as possible, but we believe that it is also desirable for the procedure to be fast and less invasive. In cases that have no adequate vein, fingertip replantation can be achieved on arterial anastomosis alone up to subzone III.

  16. A Vascular Anastomosis Simulation Can Provide a Safe and Effective Environment for Resident Skills Development.

    Science.gov (United States)

    Heelan Gladden, Alicia A; Conzen, Kendra D; Benge, Michael J; Gralla, Jane; Kennealey, Peter T

    2018-04-09

    Vascular anastomoses are complex surgical procedures, performed in time-sensitive circumstances, making intraoperative teaching more challenging. We sought to evaluate whether a vascular anastomosis simulation was effective in developing resident skills. General surgery residents participated in a vascular anastomosis simulation for 1 to 2hours during their transplant rotation. An attending transplant surgeon at the University of Colorado guided the resident through end-to-end and end-to-side anastomoses using bovine carotid artery (Artegraft). The residents completed a presimulation and postsimulation survey which quantitated their confidence. They also completed the MiSSES scale, which assessed the validity of the simulation. Twenty residents participated in the simulation and completed the surveys. The residents reported increased understanding in how to set up an end-to-end anastomosis and an end-to-side anastomosis (p = 0.001 and p = 0.009, respectively). They reported increased ability to suture, forehand and backhand with a Castro-Viejo needle driver (both p < 0.001). The residents reported increased ability to manipulate the needle (p = 0.006), and increased ability to manipulate tissue without causing trauma (p = 0.021). They reported increased confidence in tying a surgical knot with 6-0 Prolene and in operating while wearing loupes (p = 0.002, and p < 0.001, respectively). Overall, the residents reported increased confidence when asked to perform part of a vascular anastomosis in the operating room (p < 0.001). Seventeen residents completed the MiSSES scale with median scores of "somewhat agree" to "strongly agree" on all domains of the scale. The use of a simple, inexpensive vascular anastomosis simulation is an effective and safe environment to improve residents' surgical skills and the residents felt that the simulation was valid. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  17. Relationship between method of anastomosis and anastomotic failure after right hemicolectomy and ileo-caecal resection: an international snapshot audit

    NARCIS (Netherlands)

    Pinkney, T.; Battersby, N.; Bhangu, A.; Chaudhri, S.; El-Hussuna, A.; Frasson, M.; Nepogodiev, D.; Singh, B.; Vennix, S.; Zmora, O.; Altomare, D.; Bemelman, W.; Christensen, P.; D'Hoore, A.; Laurberg, S.; Morton, D.; Rubbini, M.; Vaizey, C.; Magill, L.; Perry, R.; Sheward, N.; Ives, N.; Mehta, S.; Cillo, M.; Estefania, D.; Patron Uriburu, J.; Ruiz, H.; Salomon, M.; Makhmudov, A.; Selnyahina, L.; Varabei, A.; Vizhynis, Y.; Claeys, D.; Defoort, B.; Muysoms, F.; Pletinckx, P.; Vergucht, V.; Debergh, I.; Feryn, T.; Reusens, H.; Nachtergaele, M.; Francart, D.; Jehaes, C.; Markiewicz, S.; Monami, B.; Weerts, J.; Bouckaert, W.; Houben, B.; Knol, J.; Sergeant, G.; Vangertruyden, G.; Haeck, L.; Lange, C.; Sommeling, C.; Vindevoghel, K.; Castro, S.; de Bruyn, H.; Huyghe, M.; de Wolf, E.; Reynders, D.; van Overstraeten, A. de Buck; Wolthuis, A.; Delibegovic, S.; Christiani, A.; Marchiori, M.; Rocha de Moraes, C.; Tercioti, V.; Arabadjieva, E.; Bulanov, D.; Dardanov, D.; Stoyanov, V.; Yonkov, A.; Angelov, K.; Maslyankov, S.; Sokolov, M.; Todorov, G.; Toshev, S.; Georgiev, Y.; Karashmalakov, A.; Zafirov, G.; Wang, X.; Condic, D.; Kraljik, D.; Mrkovic, H.; Pavkovic, V.; Raguz, K.; Bencurik, V.; Holaskova, E.; Skrovina, M.; Farkasova, M.; Grolich, T.; Kala, Z.; Antos, F.; Pruchova, V.; Sotona, O.; Chobola, M.; Dusek, T.; Ferko, A.; Orhalmi, J.; Hoch, J.; Kocian, P.; Martinek, L.; Bernstein, I.; Sunesen, K. Gotschalck; Leunbach, J.; Thorlacius-Ussing, O.; Oveson, A. Uth; Chirstensen, S. Dahl; Gamez, V.; Oeting, M.; Loeve, U. Schou; Ugianskis, A.; Jessen, M.; Krarup, P.; Linde, K.; Mirza, Q.; Stovring, J. Overgaard; Erritzoe, L.; Jakobsen, H. Loft; Lykke, J.; Colov, E. Palmgren; Madsen, A. Husted; Friis, T. Linde; Funder, J. Amstrup; Dich, R.; Kjaer, S.; Rasmussen, S.; Schlesinger, N.; Kjaer, M. Dilling; Qvist, N.; Khalid, A.; Ali, G.; Hadi, S.; Walker, L. Rosell; Kivela, A.; Lehtonen, T.; Lepisto, A.; Scheinin, T.; Siironen, P.; Kossi, J.; Kuusanmaki, P.; Tomminen, T.; Turunen, A.; Rautio, T.; Vierimaa, M.; Huhtinen, H.; Karvonen, J.; Lavonius, M.; Rantala, A.; Varpe, P.; Cotte, E.; Francois, Y.; Glehen, O.; Kepenekian, V.; Passot, G.; Maggiori, L.; Manceau, G.; Panis, Y.; Gout, M.; Rullier, E.; van Geluwe, B.; Chafai, N.; Lefevre, J. H.; Parc, Y.; Tiret, E.; Couette, C.; Duchalais, E.; Agha, A.; Hornberger, M.; Hungbauer, A.; Iesalnieks, I.; Weindl, I.; Crescenti, F.; Keller, M.; Kolodziejski, N.; Scherer, R.; Sterzing, D.; Bock, B.; Boehm, G.; El-Magd, M.; Krones, C.; Niewiera, M.; Buhr, J.; Cordesmeyer, S.; Hoffmann, M.; Krueckemeier, K.; Vogel, T.; Schoen, M.; Baral, J.; Lukoschek, T.; Muench, S.; Pullig, F.; Horisberger, K.; Kienle, P.; Magdeburg, J.; Post, S.; Batzalexis, K.; Germanos, S.; Agalianos, C.; Dervenis, C.; Gouvas, N.; Kanavidis, P.; Kottikias, A.; Katsoulis, I. E.; Korkolis, D.; Plataniotis, G.; Sakorafas, G.; Akrida, I.; Argentou, M.; Kollatos, C.; Lampropoulos, C.; Tsochatzis, S.; Besznyak, I.; Bursics, A.; Egyed, T.; Papp, G.; Svastics, I.; Atladottir, J.; Moller, P.; Sigurdsson, H.; Stefansson, T.; Valsdottir, E.; Andrews, E.; Foley, N.; Hechtl, D.; Majeed, M.; McCourt, M.; Hanly, A.; Hyland, J.; Martin, S.; O'Connell, P. R.; Winter, D.; Connelly, T.; Joyce, W.; Wrafter, P.; Berkovitz, R.; Avital, S.; Yahia, I. Haj; Hermann, N.; Shpitz, B.; White, I.; Lishtzinsky, Y.; Tsherniak, A.; Wasserberg, N.; Horesh, N.; Keler, U.; Pery, R.; Shapiro, R.; Tulchinsky, H.; Badran, B.; Dayan, K.; Iskhakov, A.; Lecaros, J.; Nabih, N.; Angrima, I.; Bardini, R.; Pizzolato, E.; Tonello, M.; Arces, F.; Balestri, R.; Ceccarelli, C.; Prosperi, V.; Rossi, E.; Giannini, I.; Vincenti, L.; Altomare, D. F.; Di Candido, F.; Di Iena, M.; Guglielmi, A.; Caputi-Iam-Brenghi, O.; Marsanic, P.; Mellano, A.; Muratore, A.; Annecchiarico, M.; Bencini, L.; Bona-Pasta, S. Amore; Coratti, A.; Guerra, F.; Asteria, C. R.; Boccia, L.; Gerard, L.; Pascariello, A.; Manca, G.; Marino, F.; Casaril, A.; Inama, M.; Moretto, G.; Bacchelli, C.; Carvello, M.; Mariani, N.; Montorsi, M.; Spinelli, A.; Romairone, E.; Scabini, S.; Belli, A.; Bianco, F.; de Franciscis, S.; Romano, G. Maria; Delrio, P.; Pace, U.; Rega, D.; Sassaroli, C.; Scala, D.; de Luca, R.; Ruggieri, E.; Elbetti, C.; Garzi, A.; Romoli, L.; Scatizzi, M.; Vannucchi, A.; Curletti, G.; Durante, V.; Galleano, R.; Mariani, F.; Reggiani, L.; Bellomo, R.; Infantino, A.; Franceschilli, L.; Sileri, P.; Clementi, I.; Coletta, D.; La Torre, F.; Mingoli, A.; Velluti, F.; Di Giacomo, A.; Fiorot, A.; Massani, M.; Padoan, L.; Ruffolo, C.; Caruso, S.; Franceschini, F.; Laessig, R.; Monaci, I.; Rontini, M.; de Nardi, P.; Elmore, U.; Lemma, M.; Rosati, R.; Tamburini, A.; de Luca, M.; Sartori, A.; Benevento, A.; Bottini, C.; Ferrari, C. C.; Pata, F.; Tessera, G.; Pellino, G.; Selvaggi, F.; Lanzani, A.; Romano, F.; Sgroi, G.; Steccanella, F.; Turati, L.; Yamamoto, T.; Ancans, G.; Gerkis, S.; Leja, M.; Pcolkins, A.; Sivins, A.; Latkauskas, T.; Lizdenis, P.; Saladzin-Skas, Z.; Svagzdys, S.; Tamelis, A.; Razbadauskas, A.; Sokolovas, M.; Dulskas, A.; Samalavicius, N.; Jotautas, V.; Mikalauskas, S.; Poskus, E.; Poskus, T.; Strupas, K.; Camenzuli, C.; Cini, C.; Predrag, A.; Psaila, J.; Spiteri, N.; Buskens, C.; de Groof, E. J.; Gooszen, J.; Tanis, P.; Belgers, E.; Davids, P.; Furnee, E.; Postma, E.; Pronk, A.; Smakman, N.; Clermonts, S.; Zimmerman, D.; Omloo, J.; van der Zaag, E.; van Duijvendijk, P.; Wassenaar, E.; Bruijninckx, M.; de Graff, E.; Doornebosch, P.; Tetteroo, G.; Vermaas, M.; Iordens, G.; Knops, S.; Toorenvliet, B.; van Westereenen, H. L.; Boerma, E.; Coene, P.; van der Harst, E.; van der Pool, A.; Raber, M.; Melenhorst, J.; de Castro, S.; Gerhards, M.; Arron, M.; Bremers, A.; de Wilt, H.; Ferenschild, F.; Yauw, S.; Cense, H.; Demirkiran, A.; Hunfeld, M.; Mulder, I.; Nonner, J.; Swank, H.; van Wagensveld, B.; Bolmers, M.; Briel, J.; van Geloven, A.; van Rossem, C.; Klemann, V.; Konsten, J.; Leenders, B.; Schok, T.; Bleeker, W.; Brun, M.; Helgeland, M.; Ignjatovic, D.; Oresland, T.; Yousefi, P.; Backe, I. Faten; Sjo, O. Helmer; Nesbakken, A.; Tandberg-Eriksen, M.; Cais, A.; Traeland, J. Hallvard; Herikstad, R.; Korner, H.; Lauvland, N.; Jajtner, D.; Kabiesz, W.; Rak, M.; Gmerek, L.; Horbacka, K.; Horst, N.; Krokowicz, P.; Kwiatkowski, A.; Pasnik, K.; Karcz, P.; Romaniszyn, M.; Rusek, T.; Walega, P.; Czarencki, R.; Obuszko, Z.; Sitarska, M.; Wojciech, W.; Zawadzki, M.; Amado, S.; Clara, P.; Couceiro, A.; Malaquias, R.; Rama, N.; Almeida, A.; Barbosa, E.; Cernadas, E.; Duarte, A.; Silva, P.; Costa, S.; Martinez Insua, C.; Pereira, J.; Pereira, C.; Sacchetti, M.; Carvalho Pinto, B.; Vieira Sousa, P. Jorge; Marques, R.; Oliveira, A.; Cardoso, R.; Carlos, S.; Corte-Real, J.; Moniz Pereira, P.; Souto, R.; Carneiro, C.; Marinho, R.; Nunes, V.; Rocha, R.; Sousa, M.; Leite, J.; Melo, F.; Pimentel, J.; Ventura, L.; Vila Nova, C.; Copacscu, C.; Bintintan, V.; Ciuce, C.; Dindelegan, G.; Scurtu, R.; Seicean, R.; Domansky, N.; Karachun, A.; Moiseenko, A.; Pelipas, Y.; Petrov, A.; Pravosudov, I.; Aiupov, R.; Akmalov, Y.; Parfenov, A.; Suleymanov, N.; Tarasov, N.; Jumabaev, H.; Mamedli, Z.; Rasulov, A.; Aliev, I.; Chernikovskiy, I.; Kochnev, V.; Komyak, K.; Smirnov, A.; Achkasov, S.; Bolikhov, K.; Shelygin, Y.; Sushkov, O.; Zapolskiy, A.; Gvozdenovic, M.; Jovanovic, D.; Lausevic, Z.; Cvetkovic, D.; Maravic, M.; Milovanovic, B.; Stojakovic, N.; Tripkovic, I.; Mihajlovic, D.; Nestorovic, M.; Pecic, V.; Petrovic, D.; Stanojevic, G.; Barisic, G.; Dimitrijevic, I.; Krivokapic, Z.; Markovic, V.; Popovic, M.; Aleksic, A.; Dabic, D.; Kostic, I.; Milojkovic, A.; Perunicic, V.; Lukic, D.; Petrovic, T.; Radovanovic, D.; Radovanovic, Z.; Cuk, V. M.; Cuk, V. V.; Kenic, M.; Kovacevic, B.; Krdzic, I.; Korcek, J.; Rems, M.; Toplak, J.; Escarra, J.; Gil Barrionuevo, M.; Golda, T.; Kreisler Moreno, E.; Zerpa Martin, C.; Alvarez Laso, C.; Cumplido, P.; Padin, H.; Baixauli Fons, J.; Hernandez-Lizoain, J.; Martinez-Ortega, P.; Molina-Fernandez, M.; Sanchez-Justicia, C.; Gracia Solanas, J. Antonio; Diaz de laspra, E. Cordoba; Echazarreta-Gallego, E.; Elia-Guedea, M.; Ramirez, J.; Arredondo Chaves, J.; Gonzalez, P. Diez; Elosua, T.; Sahagun, J.; Turienzo Frade, A.; Alvarez Conde, J.; Castrillo, E.; Diaz Maag, R.; Maderuelo, V.; Saldarriaga, L.; Aldrey Cao, I.; Fernandez Varela, X.; Nunez Fernandez, S.; Parajo Calvo, A.; Villar Alvarez, S.; Blesa Sierra, I.; Lozano, R.; Marquez, M.; Porcel, O.; Menendez, P.; Fernandez Hevia, M.; Flores Siguenza, L.; Jimenez Toscano, M.; Lacy Fortuny, A.; Ordonez Trujillo, J.; Espi, A.; Garcia-Botello, S.; Martin-Arevalo, J.; Moro-Valdezate, D.; Pla-Marti, V.; Blanco-Antona, F.; Abrisqueta, J.; Ibanez Canovas, N.; Lujan Mompean, J.; Escola Ripoll, D.; Martinez Gonzalez, S.; Parodi, J.; Fernandez Lopez, A.; Ramos Fernandez, M.; Castellvi Valls, J.; Ortiz de Zarate, L.; Ribas, R.; Sabia, D.; Viso, L.; Alonso Goncalves, S.; Gil Egea, M. Jose; Pascual Damieta, M.; Pera, M.; Salvans Ruiz, S.; Bernal, J.; Landete, F.; Ais, G.; Etreros, J.; Aguilo Lucia, J.; Bosca, A.; Deusa, S.; Garcia del Cano, J.; Viciano, V.; Garcia-Armengol, J.; Roig, J.; Blas, J.; Escartin, J.; Fatas, J.; Fernando, J.; Ferrer, R.; Arias Pacheco, R.; Garcia Florez, L.; Moreno Gijon, M.; Otero Diez, J.; Solar Garcia, L.; Aguilar Teixido, F.; Balaguer Ojo, C.; Bargallo Berzosa, J.; Lamas Moure, S.; Sierra, J. Enrique; Ferminan, A.; Herrerias, F.; Rufas, M.; Vinas, J.; Codina-Cazador, A.; Farres, R.; Gomez, N.; Julia, D.; Planellas, P.; Lopez, J.; Luna, A.; Maristany, C.; Munoz Duyos, A.; Puertolas, N.; Alcantara Moral, M.; Serra-Aracil, X.; Concheiro Coello, P.; Gomez, D.; Carton, C.; Miguel, A.; Reoyo Pascual, F.; Valero Cerrato, X.; Zambrano Munoz, R.; Cervera-Aldama, J.; Gonzalez, J. Garcia; Ramos-Prada, J.; Santamaria-Olabarrieta, M.; Uriguen-Echeverria, A.; Coves Alcover, R.; Espinosa Soria, J.; Fernandez Rodriguez, E.; Hernandis Villalba, J.; Maturana Ibanenz, V.; de la Torre Gonzalez, F.; Huerga, D.; Perez Viejo, E.; Rivera, A.; Ruiz Ucar, E.; Garcia-Septiem, J.; Jimenez, V.; Jimenez Miramon, J.; Ramons Rodriquez, J.; Rodriguez Alvarez, V.; Garcea, A.; Ponchietti, L.; Borda, N.; Enriquez-Navascues, J.; Saralegui, Y.; Febles Molina, G.; Nogues, E.; Rodriguez Mendez, A.; Roque Castellano, C.; Sosa Quesada, Y.; Alvarez-Gallego, M.; Pascual, I.; Rubio-Perez, I.; Diaz-San Andres, B.; Tone-Villanueva, F.; Alonso, J.; Cagigas, C.; Castillo, J.; gomez, M.; Martin-Parra, J.; Mengual Ballester, M.; Pellicer Franco, E.; Soria Aledo, V.; Valero Navarro, G.; Caballero Rodriguez, E.; Gonzalez de Chaves, P.; Hernandez, G.; Perez Alvarez, A.; Soto Sanchez, A.; Becerra Garcia, F. Cesar; Alonso Roque, J. Guillermo; Rodriguez Arias, F. Lopez; del Valle Ruiz, S. R.; Sanchez de la Villa, G.; Compan, A.; Garcia Marin, A.; Nofuentes, C.; Orts Mico, F.; Perez Auladell, V.; Carrasco, M.; Duque Perez, C.; Galvez-Pastor, S.; Navarro Garcia, I.; Sanchez Perez, A.; Enjuto, D.; Manuel Bujalance, F.; Marcelin, N.; Perez, M.; Serrano Garcia, R.; Cabrera, A.; de la Portilla, F.; Diaz-Pavon, J.; Jimenez-Rodriguez, R.; Vazquez-Monchul, J.; Daza Gonzalez, J.; Gomez Perez, R.; Rivera Castellano, J.; Roldan de la Rua, J.; Errasti Alustiza, J.; Fernandez, L.; Romeo Ramirez, J.; Sardon Ramos, J.; Cermeno Toral, B.; Alias, D.; Garcia-Olmo, D.; Guadalajara, H.; Herreros, M.; Pacheco, P.; del Castillo Diez, F.; Lima Pinto, F.; Martinez Alegre, J.; Ortega, I.; Nieto Antonio, A. Picardo; Caro, A.; Escuder, J.; Feliu, F.; Millan, M.; Alos Company, R.; Frangi Caregnato, A.; Lozoya Trujillo, R.; Rodriguez Carrillo, R.; Ruiz Carmona, M.; Alonso, N.; Ambrona Zafra, D.; Ayala Candia, B. Amilka; Bonnin Pascual, J.; Pineno Flores, C.; Alcazar Montero, J.; Angoso Clavijo, M.; Garcia, J.; Sanchez Tocino, J.; Gomez-Alcazar, C.; Costa-Navarro, D.; Ferri-Romero, J.; Rey-Riveiro, M.; Romero-Simo, M.; Arencibia, B.; Esclapez, P.; Garcia-Granero, E.; Granero, P.; Medina Fernandez, F. J.; Gallardo Herrera, A. B.; Diaz Lopez, C.; Navarro Rodriguez, E.; Torres Tordera, E.; Arenal, J.; Citores, M.; Marcos, J.; Sanchez, J.; Tinoco, C.; Espin, E.; Garcia Granero, A.; Jimenez Gomez, L.; Sanchez Garcia, J.; Vallribera, F.; Folkesson, J.; Skoldberg, F.; Bergman, K.; Borgstrom, E.; Frey, J.; Silfverberg, A.; Soderholm, M.; Nygren, J.; Segelman, J.; Gustafsson, D.; Lagerqvist, A.; Papp, A.; Pelczar, M.; Abraham-Nordling, M.; Ahlberg, M.; Sjovall, A.; Tengstrom, J.; Hagman, K.; Chabok, A.; Ezra, E.; Nikberg, M.; Smedh, K.; Tiselius, C.; Al-Naimi, N.; Duc, M. Dao; Meyer, J.; Mormont, M.; Ris, F.; Prevost, G.; Villiger, P.; Hoffmann, H.; Kettelhack, C.; Kirchhoff, P.; Oertli, D.; Weixler, B.; Aytac, B.; Leventoglu, S.; Mentes, B.; Yuksel, O.; Demirbas, S.; Ozkan, B. Busra; Ozbalci, G. Selcuk; Sungurtekin, U.; Gulcu, B.; Ozturk, E.; Yilmazlar, T.; Challand, C.; Fearnhead, N.; Hubbard, R.; Kumar, S.; Arthur, J.; Barben, C.; Skaife, P.; Slawik, S.; Williams, M.; Zammit, M.; Barker, J.; French, J.; Sarantitis, I.; Slawinski, C.; Clifford, R.; Eardley, N.; Johnson, M.; McFaul, C.; Vimalachandran, D.; Allan, S.; Bell, A.; Oates, E.; Shanmugam, V.; Brigic, A.; Halls, M.; Pucher, P.; Stubbs, B.; Agarwal, T.; Chopada, A.; Mallappa, S.; Pathmarajah, M.; Sugden, C.; Brown, C.; Macdonald, E.; Mckay, A.; Richards, J.; Robertson, A.; Kaushal, M.; Patel, P.; Tezas, S.; Touqan, N.; Ayaani, S.; Marimuthu, K.; Piramanayagam, B.; Vourvachis, M.; Iqbal, N.; Korsgen, S.; Seretis, C.; Shariff, U.; Arnold, S.; Chan, H.; Clark, E.; Fernandes, R.; Moran, B.; Bajwa, A.; McArthur, D.; Cao, K.; Cunha, P.; Pardoe, H.; Quddus, A.; Theodoropoulou, K.; Bolln, C.; Denys, G.; Gillespie, M.; Manimaran, N.; Reidy, J.; Malik, A. I.; Malik, A.; Pitt, J.; Aryal, K.; El-Hadi, A.; Lal, R.; Pal, A.; Velchuru, V.; Cunha, M. Oliveira; Thomas, M.; Bains, S.; Boyle, K.; Miller, A.; Norwood, M.; Yeung, J.; Goian, L.; Gurjar, S.; Saghir, W.; Sengupta, N.; Stewart-Parker, E.; Bailey, S.; Khalil, T.; Lawes, D.; Nikolaou, S.; Omar, G.; Church, R.; Muthiah, B.; Garrett, W.; Marsh, P.; Obeid, N.; Chandler, S.; Coyne, P.; Evans, M.; Hunt, L.; Lim, J.; Oliphant, Z.; Papworth, E.; Weaver, H.; Leon, K. Cuinas; Williams, G.; Hernon, J.; Kapur, S.; Moosvi, R.; Shaikh, I.; Swafe, L.; Aslam, M.; Evans, J.; Ihedioha, U.; Kang, P.; Merchant, J.; Hompes, R.; Middleton, R.; Broomfield, A.; Crutten-Wood, D.; Foster, J.; Nash, G.; Akhtar, M.; Boshnaq, M.; Eldesouky, S.; Mangam, S.; Rabie, M.; Ahmed, J.; Khan, J.; Goh, N. Ming; Shamali, A.; Stefan, S.; Thompson, C.; Amin, A.; Docherty, J.; Lim, M.; Walker, K.; Watson, A.; Hossack, M.; Mackenzie, N.; Paraoan, M.; Alam, N.; Daniels, I.; Narang, S.; Pathak, S.; Smart, N.; Al-Qaddo, A.; Codd, R.; Rutka, O.; Bronder, C.; Crighton, I.; Davies, E.; Raymond, T.; Bookless, L.; Griffiths, B.; Plusa, S.; Carlson, G.; Harrison, R.; Lees, N.; Mason, C.; Quayle, J.; Branagan, G.; Broadhurst, J.; Chave, H.; Sleight, S.; Awad, F.; Cruickshank, N.; Joy, H.; Boereboom, C.; Daliya, P.; Dhillon, A.; Watson, N.; Watson, R.; Artioukh, D.; Gokul, K.; Javed, M.; Kong, R.; Sutton, J.; Faiz, O.; Jenkins, I.; Leo, C. A.; Samaranayake, S. F.; Warusavitarne, J.; Arya, S.; Bhan, C.; Mukhtar, H.; Oshowo, A.; Wilson, J.; Duff, S.; Fatayer, T.; Mbuvi, J.; Sharma, A.; Cornish, J.; Davies, L.; Harries, R.; Morris, C.; Torkington, J.; Knight, J.; Lai, C.; Shihab, O.; Tzivanakis, A.; Hussain, A.; Luke, D.; Padwick, R.; Torrance, A.; Tsiamis, A.; Dawson, P.; Balfour, A.; Brady, R.; Mander, J.; Paterson, H.; Chandratreya, N.; Chu, H.; Cutting, J.; Vernon, S.; Ho, C. Wai; Andreani, S.; Patel, H.; Warner, M.; Tan, J. Yan Qi; Gidwani, A.; Lawther, R.; Loughlin, P.; Skelly, B.; Spence, R.; Iqbal, A.; Khan, A.; Perrin, K.; Raza, A.; Tan, S.

    2017-01-01

    Aim The anastomosis technique used following right-sided colonic resection is widely variable and may affect patient outcome. This study aimed to assess the association between leak and anastomosis technique (stapled vs handsewn). Method This was a prospective, multicentre, international audit

  18. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix; Gregson, James; Wetzstein, Gordon; Raskar, Ramesh; Heidrich, Wolfgang

    2014-01-01

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  19. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix

    2014-06-22

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  20. Comparative study of hand sewn single layer anastomosis of dog's bowel Estudo comparativo das anastomoses manuais em plano único do intestino delgado de cães

    OpenAIRE

    João Luiz Moreira Coutinho Azevedo; Octávio Hypólito; Otávio Cansanção Azevedo; Otávio Monteiro Becker Jr.; Dalmer Faria Freire

    2008-01-01

    BACKGROUND: Two-layer intestinal anastomosis increases the inflammatory response while single-layer anastomosis results in a better wound healing. However the four main kinds of stitches which may be chosen in performing single layer intestinal sutures never before had been comparatively studied. AIM: To compare the four more commonly used types of single layer surgical anastomosis sutures of the digestive tract. METHODS: Six mongrel dogs were operated, each one receiving two anastomosis: one...

  1. Intracranial carotid anastomosis and partial aplasia of an internal carotid artery

    International Nuclear Information System (INIS)

    Huber, G.

    1980-01-01

    A rare arterial anastomosis between the right and left interal carotid arteries at the base at the skull, with aplasia of the cervical part of the left internal carotid artery is reported. The case is unusual because, in addition to the vascular anomaly of the carotid artery, there is an aneurysm of the anterior communicating artery and bilateral renal cysts. The condition is a complex malformation syndrome caused by defective regression of the third branchial artery. Because of the characteristic angiographic aspects such a case should be called transverse carotid anastomosis. (orig.)

  2. Intracranial carotid anastomosis and partial aplasia of an internal carotid artery

    Energy Technology Data Exchange (ETDEWEB)

    Huber, G.

    1980-12-01

    A rare arterial anastomosis between the right and left internal carotid arteries at the base at the skull, with aplasia of the cervical part of the left internal carotid artery is reported. The case is unusual because, in addition to the vascular anomaly of the carotid artery, there is an aneurysm of the anterior communicating artery and bilateral renal cysts. The condition is a complex malformation syndrome caused by defective regression of the third branchial artery. Because of the characteristic angiographic aspects such a case should be called transverse carotid anastomosis.

  3. Surgical repair of a celiac artery aneurysm using a sutureless proximal anastomosis device

    Directory of Open Access Journals (Sweden)

    Tetsuro Uchida, MD, PhD

    2017-12-01

    Full Text Available Some celiac artery aneurysms are not suitable for endovascular therapy. We describe the case of a 63-year-old man with a celiac trunk aneurysm extending to the hepatosplenic bifurcation. The aneurysm was resected and oversewn at the origin from the abdominal aorta. A saphenous vein bypass from the supraceliac aorta to the celiac artery bifurcation was performed using a sutureless anastomotic device (PAS-Port system; Cardica, Redwood City, Calif to create the proximal anastomosis, eliminating the need for aortic clamping. This system is thought to make direct proximal aortic anastomosis safe and easy in patients requiring surgical reconstruction of celiac artery aneurysms.

  4. Successful pregnancy after uterovaginal anastomosis in patients with congenital atresia of cervix uteri.

    Science.gov (United States)

    Prorocic, M; Vasiljevic, M; Tasic, L; Brankovic, S

    2012-01-01

    We present a case of successful pregnancy after effective uterovaginal anastomosis in a 26-years-old patient with congenital atresia of the cervix uteri. She spontaneously achieved pregnancy after four years of uterovaginal anastomosis. Gestation was at the eighth lunar month and the delivery was done by cesarean section due to rapidly progressing fetal asphyxia. The patient gave birth to a live healthy male, weighing 1,950 g, with an Apgar score of 5 and 8 at 1 and 5 min, respectively. The postoperative course was uneventful, and leakage of lochia was normal.

  5. Feasibility of a laser or charged-particle-beam fusion-reactor concept with direct electric generation by magnetic-flux compression

    International Nuclear Information System (INIS)

    Lasche, G.P.

    1983-06-01

    A new concept for an inertial-confinement fusion reactor is described which, because of its fundamentally different approach to blanket geometry and energy conversion, makes possible a unique combination of high efficiency, high power density, and low radioactivity. The conventional blanket is replaced with a liquid-density mass of lithium contiguously surrounding the fusion yield. This compact blanket configuration produces the maximum shock-induced kinetic energy in liquid metal and the maximum neutron absorption per unit mass. The shock-induced kinetic energy of the liquid lithium is converted directly to electricity with high efficiency by work done against a pulsed normal-conducting magnetic field applied to the exterior of the lithium

  6. Mining compressing sequential problems

    NARCIS (Netherlands)

    Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

    2012-01-01

    Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

  7. Adenocarcinoma in the anal canal after ileal pouch-anal anastomosis for familial adenomatous polyposis using a double-stapled technique: report of two cases

    NARCIS (Netherlands)

    Vrouenraets, Bart C.; van Duijvendijk, Peter; Bemelman, Willem A.; Offerhaus, G. Johan A.; Slors, J. Frederik M.

    2004-01-01

    Restorative proctocolectomy with an ileal pouch-anal anastomosis is thought to abolish the risk of colorectal adenoma development in patients suffering from familial adenomatous polyposis. Both after mucosectomy with a handsewn anastomosis and after a double-stapled anastomosis, rectal mucosa is

  8. Magnetic

    Science.gov (United States)

    Aboud, Essam; El-Masry, Nabil; Qaddah, Atef; Alqahtani, Faisal; Moufti, Mohammed R. H.

    2015-06-01

    The Rahat volcanic field represents one of the widely distributed Cenozoic volcanic fields across the western regions of the Arabian Peninsula. Its human significance stems from the fact that its northern fringes, where the historical eruption of 1256 A.D. took place, are very close to the holy city of Al-Madinah Al-Monawarah. In the present work, we analyzed aeromagnetic data from the northern part of Rahat volcanic field as well as carried out a ground gravity survey. A joint interpretation and inversion of gravity and magnetic data were used to estimate the thickness of the lava flows, delineate the subsurface structures of the study area, and estimate the depth to basement using various geophysical methods, such as Tilt Derivative, Euler Deconvolution and 2D modeling inversion. Results indicated that the thickness of the lava flows in the study area ranges between 100 m (above Sea Level) at the eastern and western boundaries of Rahat Volcanic field and getting deeper at the middle as 300-500 m. It also showed that, major structural trend is in the NW direction (Red Sea trend) with some minor trends in EW direction.

  9. MAGNET

    CERN Multimedia

    Benoit Curé

    The cooling down to the nominal temperature of 4.5 K was achieved at the beginning of August, in conjunction with the completion of the installation work of the connection between the power lines and the coil current leads. The temperature gradient on the first exchanger of the cold box is now kept within the nominal range. A leak of lubricant on a gasket of the helium compressor station installed at the surface was observed and several corrective actions were necessary to bring the situation back to normal. The compressor had to be refilled with lubricant and a regeneration of the filters and adsorbers was necessary. The coil cool down was resumed successfully, and the cryogenics is running since then with all parameters being nominal. Preliminary tests of the 20kA coil power supply were done earlier at full current through the discharge lines into the dump resistors, and with the powering busbars from USC5 to UXC5 without the magnet connected. On Monday evening August 25th, at 8pm, the final commissionin...

  10. MAGNET

    CERN Document Server

    B. Curé

    The first phase of the commissioning ended in August by a triggered fast dump at 3T. All parameters were nominal, and the temperature recovery down to 4.5K was carried out in two days by the cryogenics. In September, series of ramps were achieved up to 3 and finally 3.8T, while checking thoroughly the detectors in the forward region, measuring any movement of and around the HF. After the incident of the LHC accelerator on September 19th, corrective actions could be undertaken in the forward region. When all these displacements were fully characterized and repetitive, with no sign of increments in displacement at each field ramp, it was possible to start the CRAFT, Cosmic Run at Four Tesla (which was in fact at 3.8T). The magnet was ramped up to 18.16kA and the 3 week run went smoothly, with only 4 interruptions: due to the VIP visits on 21st October during the LHC inauguration day; a water leak on the cooling demineralized water circuit, about 1 l/min, that triggered a stop of the cooling pumps, and resulte...

  11. MAGNET

    CERN Multimedia

    Benoit Curé

    2013-01-01

    Maintenance work and consolidation activities on the magnet cryogenics and its power distribution are progressing according to the schedules. The manufacturing of the two new helium compressor frame units has started. The frame units support the valves, all the sensors and the compressors with their motors. This activity is subcontracted. The final installation and the commissioning at CERN are scheduled for March–April 2014. The overhauls of existing cryogenics equipment (compressors, motors) are in progress. The reassembly of the components shall start in early 2014. The helium drier, to be installed on the high-pressure helium piping, has been ordered and will be delivered in the first trimester of 2014. The power distribution for the helium compressors in SH5 on the 3.3kV network is progressing. The 3.3kV switches, between each compressor and its hot spare compressor, are being installed, together with the power cables for the new compressors. The 3.3kV electrical switchboards in SE5 will ...

  12. Stapled side-to-side anastomosis might be better than handsewn end-to-end anastomosis in ileocolic resection for Crohn's disease: a meta-analysis.

    Science.gov (United States)

    He, Xiaosheng; Chen, Zexian; Huang, Juanni; Lian, Lei; Rouniyar, Santosh; Wu, Xiaojian; Lan, Ping

    2014-07-01

    Ileocolic anastomosis is an essential step in the treatment to restore continuity of the gastrointestinal tract following ileocolic resection in patients with Crohn's disease (CD). However, the association between anastomotic type and surgical outcome is controversial. The aim of this meta-analysis is to compare surgical outcomes between stapled side-to-side anastomosis (SSSA) and handsewn end-to-end anastomosis (HEEA) after ileocolic resection in patients with CD. Studies comparing SSSA with HEEA after ileocolic resection in patients with CD were identified in PubMed and EMBASE. Outcomes such as complication, recurrence, and re-operation were evaluated. Eight studies (three randomized controlled trials, one prospective non-randomized trial, and four non-randomized retrospective trials) comparing SSSA (396 cases) and HEEA (425 cases) were included. As compared with HEEA, SSSA was superior in terms of overall postoperative complications [odds ratio (OR), 0.54; 95 % confidence interval (CI) 0.32-0.93], anastomotic leak (OR 0.45; 95 % CI 0.20-1.00), recurrence (OR 0.20; 95 % CI 0.07-0.55), and re-operation for recurrence (OR 0.18; 95 % CI 0.07-0.45). Postoperative hospital stay, mortality, and complications other than anastomotic leak were comparable. Based on the results of our meta-analysis, SSSA would appear to be the preferred procedure after ileocolic resection for CD, with reduced overall postoperative complications, especially anastomotic leak, and a decreased recurrence and re-operation rate.

  13. Adiabatic compression of ion rings

    International Nuclear Information System (INIS)

    Larrabee, D.A.; Lovelace, R.V.

    1982-01-01

    A study has been made of the compression of collisionless ion rings in an increasing external magnetic field, B/sub e/ = zB/sub e/(t), by numerically implementing a previously developed kinetic theory of ring compression. The theory is general in that there is no limitation on the ring geometry or the compression ratio, lambdaequivalentB/sub e/ (final)/B/sub e/ (initial)> or =1. However, the motion of a single particle in an equilibrium is assumed to be completely characterized by its energy H and canonical angular momentum P/sub theta/ with the absence of a third constant of the motion. The present computational work assumes that plasma currents are negligible, as is appropriate for a low-temperature collisional plasma. For a variety of initial ring geometries and initial distribution functions (having a single value of P/sub theta/), it is found that the parameters for ''fat'', small aspect ratio rings follow general scaling laws over a large range of compression ratios, 1 3 : The ring radius varies as lambda/sup -1/2/; the average single particle energy as lambda/sup 0.72/; the root mean square energy spread as lambda/sup 1.1/; and the total current as lambda/sup 0.79/. The field reversal parameter is found to saturate at values typically between 2 and 3. For large compression ratios the current density is found to ''hollow out''. This hollowing tends to improve the interchange stability of an embedded low β plasma. The implications of these scaling laws for fusion reactor systems are discussed

  14. Compression for radiological images

    Science.gov (United States)

    Wilson, Dennis L.

    1992-07-01

    The viewing of radiological images has peculiarities that must be taken into account in the design of a compression technique. The images may be manipulated on a workstation to change the contrast, to change the center of the brightness levels that are viewed, and even to invert the images. Because of the possible consequences of losing information in a medical application, bit preserving compression is used for the images used for diagnosis. However, for archiving the images may be compressed to 10 of their original size. A compression technique based on the Discrete Cosine Transform (DCT) takes the viewing factors into account by compressing the changes in the local brightness levels. The compression technique is a variation of the CCITT JPEG compression that suppresses the blocking of the DCT except in areas of very high contrast.

  15. Radiological Image Compression

    Science.gov (United States)

    Lo, Shih-Chung Benedict

    The movement toward digital images in radiology presents the problem of how to conveniently and economically store, retrieve, and transmit the volume of digital images. Basic research into image data compression is necessary in order to move from a film-based department to an efficient digital -based department. Digital data compression technology consists of two types of compression technique: error-free and irreversible. Error -free image compression is desired; however, present techniques can only achieve compression ratio of from 1.5:1 to 3:1, depending upon the image characteristics. Irreversible image compression can achieve a much higher compression ratio; however, the image reconstructed from the compressed data shows some difference from the original image. This dissertation studies both error-free and irreversible image compression techniques. In particular, some modified error-free techniques have been tested and the recommended strategies for various radiological images are discussed. A full-frame bit-allocation irreversible compression technique has been derived. A total of 76 images which include CT head and body, and radiographs digitized to 2048 x 2048, 1024 x 1024, and 512 x 512 have been used to test this algorithm. The normalized mean -square-error (NMSE) on the difference image, defined as the difference between the original and the reconstructed image from a given compression ratio, is used as a global measurement on the quality of the reconstructed image. The NMSE's of total of 380 reconstructed and 380 difference images are measured and the results tabulated. Three complex compression methods are also suggested to compress images with special characteristics. Finally, various parameters which would effect the quality of the reconstructed images are discussed. A proposed hardware compression module is given in the last chapter.

  16. Compression and archiving of digital images

    International Nuclear Information System (INIS)

    Huang, H.K.

    1988-01-01

    This paper describes the application of a full-frame bit-allocation image compression technique to a hierarchical digital image archiving system consisting of magnetic disks, optical disks and an optical disk library. The digital archiving system without the compression has been in clinical operation in the Pediatric Radiology for more than half a year. The database in the system consists of all pediatric inpatients including all images from computed radiography, digitized x-ray films, CT, MR, and US. The rate of image accumulation is approximately 1,900 megabytes per week. The hardware design of the compression module is based on a Motorola 68020 microprocessor, A VME bus, a 16 megabyte image buffer memory board, and three Motorola digital signal processing 56001 chips on a VME board for performing the two-dimensional cosine transform and the quantization. The clinical evaluation of the compression module with the image archiving system is expected to be in February 1988

  17. FRC translation into a compression coil

    International Nuclear Information System (INIS)

    Chrien, R.E.

    1985-01-01

    Several features of the problem of FRC translation into a compression coil are considered. First, the magnitude of the guide field is calculated and found to exceed that which would be applied to a flux conserver. Second, energy conservation is applied to FRC translation from a flux conserver into a compression coil. It is found that a significant temperature decrease is required for translation to be energetically possible. The temperature change depends on the external inductance in the compression circuit. An analogous case is that of a compression region composed of a compound magnet; in this case the temperature change depends on the ratio of inner and outer coil radii. Finally, the kinematics of intermediate translation states are calculated using an ''abrupt transition'' model. It is found, in this model, that the FRC must overcome a potential hill during translation, which requires a small initial velocity

  18. Antiproton compression and radial measurements

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jorgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page R D; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wurtele, J S; Yamazaki, Y

    2008-01-01

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, achieved by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile, and its relation to that of the electron plasma. We also measure the outer radial profile by ejecting antiprotons to the trap wall using an octupole magnet.

  19. Colectomy and ileorectal anastomosis is still an option for selected patients with familial adenomatous polyposis

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulow, C.; Vasen, H.

    2008-01-01

    PURPOSE: The risk of rectal cancer after colectomy and ileorectal anastomosis may be reduced in the last decades, as patients with severe polyposis now have an ileoanal pouch. We have reevaluated the risk of rectal cancer and proctectomy for all causes according to the year of operation. METHODS:...

  20. Randomized clinical trial of biodegradeable intraluminal sheath to prevent anastomotic leak after stapled colorectal anastomosis

    NARCIS (Netherlands)

    Bakker, I S; Morks, A N; Ten Cate Hoedemaker, H O; Burgerhof, J G M; Leuvenink, H G; van Praagh, J B; Ploeg, R J; Havenga, K

    Background: Anastomotic leakage is a potential major complication after colorectal surgery. The C-seal was developed to help reduce the clinical leakage rate. It is an intraluminal sheath that is stapled proximal to a colorectal anastomosis, covering it intraluminally and thus preventing intestinal

  1. Effect of Previous Irradiation on Vascular Thrombosis of Microsurgical Anastomosis: A Preclinical Study in Rats

    Science.gov (United States)

    Gallardo-Calero, Irene; López-Fernández, Alba; Romagosa, Cleofe; Vergés, Ramona; Aguirre-Canyadell, Marius; Soldado, Francisco; Velez, Roberto

    2016-01-01

    Background: The objective of the present investigation was to compare the effect of neoadjuvant irradiation on the microvascular anastomosis in cervical bundle using an experimental model in rats. Methods: One hundred forty male Sprague–Dawley rats were allocated into 4 groups: group I, control, arterial microanastomosis; group II, control, venous microanastomosis; group III, arterial microanastomosis with previous irradiation (20 Gy); and group IV, venous microanastomosis with previous irradiation (20 Gy). Clinical parameters, technical values of anastomosis, patency, and histopathological parameters were evaluated. Results: Irradiated groups (III and IV) and vein anastomosis groups (II and IV) showed significantly increased technical difficulties. Group IV showed significantly reduced patency rates (7/35) when compared with the control group (0/35). Radiotherapy significantly decreased the patency rates of the vein (7/35) when compared with the artery (1/35). Groups III and IV showed significantly reduced number of endothelial cells and also showed the presence of intimal thickening and adventitial fibrosis as compared with the control group. Conclusion: Neoadjuvant radiotherapy reduces the viability of the venous anastomosis in a preclinical rat model with a significant increase in the incidence of vein thrombosis. PMID:27975009

  2. [Terminolateral esophagojejunostomy after gastrectomy with the biofragmentable anastomosis ring in the dog model].

    Science.gov (United States)

    Dietz, U A; Araújo, A C F; Czeczko, N G; Lemos, R; Araújo, U; Inácio, C M; Salles, G; Corrêa Neto, M; Repka, J C D; Zanellato, C M F; Malafaia, O; Debus, E S; Thiede, A

    2005-06-01

    Esophagojejunostomy after total gastrectomy still remains a high risk anastomosis with a considerable morbidity and mortality. The majority of these anastomoses are performed by the intraluminal stapler technique, yet stenoses are a known late complication even after an uneventful postoperative course. In the present study, the osophagojejunostomy with the biofragmentable anastomosis ring (BAR) was examined in dogs. 28 dogs were randomized into a group of manual suture (n = 14) and a BAR-group (n = 14). After gastrectomy, the esophagojejunostomy was performed by hand-suture with polypropylene 4-0 in the manual suture group, and with the 25/1.5 mm BAR in the BAR-group. In both groups the Roux-en-Y jejunojejunostomy was performed by hand-suture. The dogs were evaluated on postoperative days 4, 7 and 14 with regard to macroscopy, bursting strength, tissue hydroxyproline and histology. There was one leakage without clinical effect in the hand-sewn group on postoperative day 4; there was no leak in the BAR-group. In observing fibre-free enteral feeding, neither functional disorders nor obstruction of the BAR were observed. The general anastomosis parameters were matchable between the groups. The infracarinal BAR-esophagojejunostomy is comparable to the hand-sewn anastomosis in the dog-model.

  3. Predictors of Bowel Function in Long-term Rectal Cancer Survivors with Anastomosis.

    Science.gov (United States)

    Alavi, Mubarika; Wendel, Christopher S; Krouse, Robert S; Temple, Larissa; Hornbrook, Mark C; Bulkley, Joanna E; McMullen, Carmit K; Grant, Marcia; Herrinton, Lisa J

    2017-11-01

    Bowel function in long-term rectal cancer survivors with anastomosis has not been characterized adequately. We hypothesized that bowel function is associated with patient, disease, and treatment characteristics. The cohort study included Kaiser Permanente members who were long-term (≥5 years) rectal cancer survivors with anastomosis. Bowel function was scored using the self-administered, 14-item Memorial Sloan-Kettering Cancer Center Bowel Function Index. Patient, cancer, and treatment variables were collected from the electronic medical chart. We used multiple regression to assess the relationship of patient- and treatment-related variables with the bowel function score. The study included 381 anastomosis patients surveyed an average 12 years after their rectal cancer surgeries. The total bowel function score averaged 53 (standard deviation, 9; range, 31-70, higher scores represent better function). Independent factors associated with worse total bowel function score included receipt of radiation therapy (yes vs. no: 5.3-unit decrement, p 6 cm: 3.2-unit decrement, p decrement, p decrement, p model explained 20% of the variation in the total bowel function score. Low tumor location, radiation therapy, temporary ostomy during initial treatment, and history of smoking were linked with decreased long-term bowel function following an anastomosis. These results should improve decision-making about surgical options.

  4. Bricker's ileal conduit urinary diversion with a simple non-refluxing uretero ileal anastomosis

    DEFF Research Database (Denmark)

    Bernstein, I T; Bennicke, K; Rørdam, P

    1991-01-01

    anastomosis. which was treated successfully by two weeks drainage. Hydronephrosis deteriorated in 18 (26%) of the renal units, remained unchanged in 39 (57%) and improved in 11 (16%). Increases in plasma creatinine concentrations up to 200 mumol/l were found in eight patients, and in one patient it increased...

  5. Comparison of Colonic J-pouch and Straight Coloanal anastomosis after Low Anterior Resection.

    Science.gov (United States)

    Mehrvarz, Shaban; Towliat, Seyed Mohsen; Mohebbi, Hassan Ali; Derakhshani, Saieed; Abavisani, Mahdi

    2013-01-01

    The tendency towards sphincter preserving for low rectal cancers with low anterior resection, has led to the technique of straight coloanal anastomosis (SCAA) or colonic J-pouch anal anastomosis (CPAA). The aim of our study was to compare functional outcomes, complication rates and quality of life (QoL) after LAR with either a straight or colonic J pouch anastomosis. In 88 patients with rectal tumors located in lower third, who were candidate for LAR with coloanal anastomosis. They were divided for reconstruction using either SCAA (n= 47) or CPAA (n= 41) from January 2007 to May 2009. Functional results were assessed after closure of temporary loop ileostomy, 6 months postoperatively. Quality of life (QoL) was measured using European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30. The two groups were matched for gender, age, and preoperative chemotherapy and radiotherapy. There were no significant differences between the SCAA and CPAA groups relative to anastomotic leakage. Among patients with CPAA, the mean of 24 hours bowel movements, daytime bowel movements, incontinence scores, and incidence of urgency were significantly lower than those in the SCAA group. Also, patients with a CPAA had a significantly better quality of life. CPAA provided not only better functional results than SCAA, but also improved quality of life, thus may be the better choice.

  6. Risk factors for anastomotic leakage after laparoscopic low anterior resection with DST anastomosis.

    Science.gov (United States)

    Kawada, Kenji; Hasegawa, Suguru; Hida, Koya; Hirai, Kenjiro; Okoshi, Kae; Nomura, Akinari; Kawamura, Junichiro; Nagayama, Satoshi; Sakai, Yoshiharu

    2014-10-01

    Laparoscopic rectal surgery involving rectal transection and anastomosis with stapling devices is technically difficult. The aim of this study was to evaluate the risk factors for anastomotic leakage (AL) after laparoscopic low anterior resection (LAR) with double-stapling technique (DST) anastomosis. This was a retrospective single-institution study of 154 rectal cancer patients who underwent laparoscopic LAR with DST anastomosis between June 2005 and August 2013. Patient-, tumor-, and surgery-related variables were examined by univariate and multivariate analyses. The outcome of interest was clinical AL. The overall AL rate was 12.3% (19/154). In univariate analysis, tumor size (P = 0.001), operative time (P = 0.049), intraoperative bleeding (P = 0.037), lateral lymph node dissection (P = 0.009), multiple firings of the linear stapler (P = 0.041), and precompression before stapler firings (P = 0.008) were significantly associated with AL. Multivariate analysis identified tumor size (odds ratio [OR] 4.01; 95% confidence interval [CI] 1.25-12.89; P = 0.02) and precompression before stapler firings (OR 4.58; CI 1.22-17.20; P = 0.024) as independent risk factors for AL. In particular, precompression before stapler firing tended to reduce the AL occurring in early postoperative period. Using appropriate techniques, laparoscopic LAR with DST anastomosis can be performed safely without increasing the risk of AL. Important risk factors for AL were tumor size and precompression before stapler firings.

  7. Circumferential tracheal resection with primary anastomosis for post-intubation tracheal stenosis: study of 24 cases.

    Science.gov (United States)

    Negm, Hesham; Mosleh, Mohamed; Fathy, Hesham

    2013-09-01

    The objective of this study is to evaluate the results of circumferential tracheal and cricotracheal resection with primary anastomosis for the treatment of post-intubation tracheal and cricotracheal stenosis. This is a retrospective analytical study. A total number of 24 patients were included in this study. The relevant preoperative, operative and postoperative records were collected and analyzed. Twenty patients were finally symptom-free reflecting an anastomosis success rate of 83.3 %. Variable grades of anastomotic restenosis occurred in 11 (45.8 %) patients, three patients were symptom-free and eight had airway obstructive symptoms. Four out of the eight patients with symptomatic restenosis were symptom-free with endoscopic dilatation while the remaining four patients required a permanent airway appliance (T-tube, tracheostomy) for the relief of airway obstruction and this group was considered as anastomotic failure. Cricoid involvement, associated cricoid resection and the type of anastomosis were the variables that had statistical impact on the occurrence of restenosis (P = 0.017, 0.017, 0.05; respectively). Tracheal resection with primary anastomosis is a safe effective treatment method for post-intubation tracheal stenosis in carefully selected patients. Restenosis does not always mean failure of the procedure since it may be successfully managed with endoscopic dilatation.

  8. [Descending hypoglossal branch-facial nerve anastomosis in treating unilateral facial palsy after acoustic neuroma resection].

    Science.gov (United States)

    Liang, Jiantao; Li, Mingchu; Chen, Ge; Guo, Hongchuan; Zhang, Qiuhang; Bao, Yuhai

    2015-12-15

    To evaluate the efficiency of the descending hypoglossal branch-facial nerve anastomosis for the severe facial palsy after acoustic neuroma resection. The clinical data of 14 patients (6 males, 8 females, average age 45. 6 years old) underwent descending hypoglossal branch-facial nerve anastomosis for treatment of unilateral facial palsy was analyzed retrospectively. All patients previously had undergone resection of a large acoustic neuroma. House-Brackmann (H-B) grading system was used to evaluate the pre-, post-operative and follow up facial nerve function status. 12 cases (85.7%) had long follow up, with an average follow-up period of 24. 6 months. 6 patients had good outcome (H-B 2 - 3 grade); 5 patients had fair outcome (H-B 3 - 4 grade) and 1 patient had poor outcome (H-B 5 grade) Only 1 patient suffered hemitongue myoparalysis owing to the operation. Descending hypoglossal branch-facial nerve anastomosis is effective for facial reanimation, and it has little impact on the function of chewing, swallowing and pronunciation of the patients compared with the traditional hypoglossal-facial nerve anastomosis.

  9. Early and late complications among long-term colorectal cancer survivors with ostomy or anastomosis.

    Science.gov (United States)

    Liu, Liyan; Herrinton, Lisa J; Hornbrook, Mark C; Wendel, Christopher S; Grant, Marcia; Krouse, Robert S

    2010-02-01

    Among long-term (>or=5 y) colorectal cancer survivors with permanent ostomy or anastomosis, we compared the incidence of medical and surgical complications and examined the relationship of complications with health-related quality of life. The incidence and effects of complications on long-term health-related quality of life among colorectal cancer survivors are not adequately understood. Participants (284 survivors with ostomies and 395 survivors with anastomoses) were long-term colorectal cancer survivors enrolled in an integrated health plan. Health-related quality of life was assessed via mailed survey questionnaires from 2002 to 2005. Information on colorectal cancer, surgery, comorbidities, and complications was obtained from computerized data and analyzed by use of survival analysis and logistic regression. Ostomy and anastomosis survivors were followed up for an average of 12.1 and 11.2 years, respectively. Within 30 days of surgery, 19% of ostomy survivors and 10% of anastomosis survivors experienced complications (P Ostomy was associated with long-term fistula (odds ratio, 5.4; 95% CI 1.4-21.2), and among ostomy survivors, fistula was associated with reduced health-related quality of life (P ostomy have more complications early in their survivorship period, but complications among anastomosis survivors catch up after 20 years, when the 2 groups have convergent complication rates. Among colorectal cancer survivors with ostomy, fistula has especially important implications for health-related quality of life.

  10. An intraluminal prosthesis may improve healing of a one-layer colonic anastomosis

    DEFF Research Database (Denmark)

    Buch, N; Glad, H; Svendsen, P

    2002-01-01

    days postoperatively. RESULTS: Three quarters of the tubes (n = 8) dissolved in less than 2 hours. Histological examination showed significantly better structured layers and more mucosal epithelial covering in the SBS group. The other histological variables examined were: tissue gap (p ... of the anastomosis and may improve healing, possibly because of better apposition of the cut ends and reduced tension in the sutures....

  11. Cardiovascular Surgery Residency Program: Training Coronary Anastomosis Using the Arroyo Simulator and UNIFESP Models.

    Science.gov (United States)

    Maluf, Miguel Angel; Gomes, Walter José; Bras, Ademir Massarico; Araújo, Thiago Cavalcante Vila Nova de; Mota, André Lupp; Cardoso, Caio Cesar; Coutinho, Rafael Viana dos S

    2015-01-01

    Engage the UNIFESP Cardiovascular Surgery residents in coronary anastomosis, assess their skills and certify results, using the Arroyo Anastomosis Simulator and UNIFESP surgical models. First to 6th year residents attended a weekly program of technical training in coronary anastomosis, using 4 simulation models: 1. Arroyo simulator; 2. Dummy with a plastic heart; 3. Dummy with a bovine heart; and 4. Dummy with a beating pig heart. The assessment test was comprised of 10 items, using a scale from 1 to 5 points in each of them, creating a global score of 50 points maximum. The technical performance of the candidate showed improvement in all items, especially manual skill and technical progress, critical sense of the work performed, confidence in the procedure and reduction of the time needed to perform the anastomosis after 12 weeks practice. In response to the multiplicity of factors that currently influence the cardiovascular surgeon training, there have been combined efforts to reform the practices of surgical medical training. 1 - The four models of simulators offer a considerable contribution to the field of cardiovascular surgery, improving the skill and dexterity of the surgeon in training. 2 - Residents have shown interest in training and cooperate in the development of innovative procedures for surgical medical training in the art.

  12. Sources and severity of self-reported food intolerance after ileal pouch-anal anastomosis

    NARCIS (Netherlands)

    Steenhagen, E.; Roos, de N.M.; Bouwman, C.A.; Laarhoven, van C.J.H.M.; Staveren, van W.A.

    2006-01-01

    Data on food intolerance after ileal pouch-anal anastomosis are scarce. The aim of this study was to identify foods causing intolerance and to determine the nature and severity of reported symptoms. Patients from the Dutch Crohn's and Ulcerative Colitis Association were mailed a survey on food

  13. Effects of combined pulse electromagnetic field stimulation plus glutamine on the healing of colonic anastomosis in rats.

    Science.gov (United States)

    Girgin, Sadullah; Gedik, Ercan; Ozturk, Hayrettin; Akpolat, Veysi; Akbulut, Veysi; Kale, Ebru; Buyukbayram, Huseyin; Celik, Salih

    2009-04-01

    An experimental study was designed to investigate the effect of combined pulse electromagnetic field (PEMF) stimulation plus glutamine administration on colonic anastomosis. Anastomosis of the left colon was performed in 28 rats, which were divided into four groups; Group 1: normal resection anastomosis plus oral 50 mg/kg/day glutamine; Group 2: normal resection anastomosis plus PEMF stimulation plus oral 50 mg/kg/day glutamine; Group 3: normal resection anastomosis plus PEMF stimulation; Group 4: normal resection anastomosis. On the seventh postoperative day, the animals were killed and the bursting pressure and tissue hydroxyproline concentration of the anastomosis were analyzed and compared. The mean anastomotic bursting pressure in Group 2 was significantly higher than in Groups 1 and 4. On the other hand, the mean anastomotic bursting pressure in Group 1 was significantly higher than in Group 4. The collagen deposition and the fibroblast infiltration were significantly increased on the seventh day in Group 3 compared the other groups. On the other hand, Groups 1 and 2 had higher scores for collagen deposition and fibroblast infiltration than Group 4. In conclusion, burst pressures, hydroxyproline, and histologic features (fibroblast infiltration and collagen deposition) were improved in the PEMF group, and both PEMF and glutamine-enriched nutrition provide a significant gain in the strength of colonic anastomoses in rats.

  14. The use of disposable skin staples for intestinal resection and anastomosis in 63 dogs: 2000 to 2014.

    Science.gov (United States)

    Rosenbaum, J M; Coolman, B R; Davidson, B L; Daly, M L; Rexing, J F; Eatroff, A E

    2016-11-01

    To describe the use of disposable skin staples for intestinal resection and anastomosis in dogs and report associated dehiscence and mortality rates. Retrospective evaluation of medical records of dogs that underwent intestinal resection and anastomosis using disposable skin staples between 2000 and 2014. Data regarding patient signalment, indication for surgery, location of the resection and anastomosis, number of procedures performed, evidence of peritonitis at the time of surgery, surgeon qualifications, dehiscence, and mortality were obtained from the medical records. Mortality was defined as failure to survive beyond 10 days following resection and anastomosis. The overall mortality rate of patients undergoing intestinal resection and anastomosis was 12·7% (8/63). The most common indication for resection and anastomosis was neoplasia (20/63 [31·7%]), followed by foreign body removal (19/63 [30·2%]). The overall dehiscence rate was 4·8% (3/63). No difference in mortality associated with indication for surgery, whether multiple procedures were performed, surgeon qualifications, or evidence of peritonitis at the time of surgery was identified. In this retrospective study, the overall mortality and dehiscence rates using disposable skin staples were similar to previously reported outcomes following resection and anastomosis. © 2016 British Small Animal Veterinary Association.

  15. Suture-free technique for canine ureteral resection-anastomosis using a microvascular anastomotic system: a cadaveric study.

    Science.gov (United States)

    Wavreille, Vincent; Adin, Christopher A; Arango, Johnattan; Ham, Kathleen L; Byron, Julie K; McLoughlin, Mary A

    2015-01-01

    To describe a suture-free technique for canine ureteral resection-anastomosis using a microvascular anastomotic system (MAS) and to compare surgical time and burst pressure of hand-sewn (HS) ureteral end-to-end anastomosis with the MAS technique. Experimental ex vivo study. Canine cadavers (n = 8). For each cadaver, 1 ureter was randomly assigned to undergo HS anastomosis and the contralateral ureter had MAS anastomosis. The first 3 cadavers (6 ureters) were used to refine the MAS technique. In the other 5 dogs, surgical time and ureteral burst pressure were compared between groups (n = 5 ureters/group). Preliminary procedures showed that selective impaling of the mucosa and submucosa (without muscularis and adventitia) is necessary to allow complete mechanical interlock of the anastomotic rings for the MAS technique. Median anastomotic time was significantly shorter for MAS (7.6 min) than HS (16.6 min; p = .029) and burst pressure higher for MAS (393 cm H2 O) than HS (180 cm H2 O; p = .012). This study demonstrated the feasibility of a suture-free technique of canine ureteral resection-anastomosis using a commercially available MAS. The MAS anastomosis was faster and had higher burst strength compared with the HS anastomosis. © Copyright 2014 by The American College of Veterinary Surgeons.

  16. Tamai zone I fingertip replantation: is external bleeding obligatory for survival of artery anastomosis-only replanted digits?

    Science.gov (United States)

    Chen, Ko-Kang; Hsieh, Tung-Ying; Chang, Kao-Ping

    2014-10-01

    Distal fingertip replantation is associated with good functional and aesthetic results. Venous anastomosis is the most challenging procedure. For replantation with an artery anastomosis-only procedure (no venous anastomosis), some protocols have been designed to relieve venous congestion involve anticoagulation and the creation of wounds for persistent bleeding. This report presents the authors' experience of fingertip survival after artery anastomosis-only replantation with no persistent external bleeding. Twelve Tamai zone I fingertip total amputation patients who underwent artery anastomosis-only replantations were recruited from February 2009 to June 2012. Nerve repair was performed if identified. The patients were not subjected to conventional external bleeding methods. Both the blood color on pinprick and fingertip temperature difference between the replanted and uninjured digits were used as indicators of deteriorated venous congestion. The replanted digits of 11 patients survived. The only failed replant exhibited an average temperature difference of more than 6°C compared with the uninjured digits and consistently exhibited darker blood during the pinprick test. All other replants exhibited average temperature differences of less than 6°C. In these Tamai zone I artery anastomosis-only replantations, fingertips survived without the use of external bleeding method, indicating that external bleeding is probably not obligatory for survival of artery anastomosis-only replanted digits distal to Tamai zone I. An increasing temperature difference between the replanted and uninjured digits and darker blood on pinprick may be used as indicators of deteriorating congestion signs. © 2014 Wiley Periodicals, Inc.

  17. Predictors of patency after two-stitch invagination vaso-epididymal anastomosis for idiopathic obstructive azoospermia

    Directory of Open Access Journals (Sweden)

    G Gautam

    2005-01-01

    Full Text Available Objectives: Anastomotic patency with return of sperm in the ejaculate following microsurgical vasoepididymostomy (VEA is not universal and may be delayed. The ability to predict the result of VEA based on preoperative or intra-operative parameters would enable the surgeon to offer the best treatment to the infertile couple. We used the two-stitch invagination technique of VEA in patients of idiopathic obstructive azoospermia and prospectively analyzed factors that could predict a patent anastomosis. While such studies have previously been done for patients undergoing VEA for secondary infertility following a vasectomy, to the best of our knowledge this is the first study analyzing these parameters for patients with primary infertility and idiopathic obstruction. Methods and materials: Over a 2-year period, 29 men underwent the 2-suture invagination VEA for idiopathic obstructive azoospermia. Twenty-four patients provided at least one postoperative semen sample. Preoperative and intra-operative parameters were compared between patients with a patent anastomosis with sperm in ejaculate (n = 12 and those with no sperm in the ejaculate (n = 12 using the t-test, Fisher′s exact test or chi-square test, as appropriate and a multivariate statistical analysis to determine any significant difference. Results: The mean follow up of the 24 patients was 7.6 months (2-30 months. A significantly greater number of patients with patent anastomosis had motile epididymal sperms (P = 0.034 and higher surgeon′s technical satisfaction with the procedure (P = 0.034. However, this difference was seen only on a univariate analysis and did not persist when a multivariate analysis was used. Conclusions: The presence of motile sperms in the epididymal fluid and a high level of technical satisfaction with the anastomosis may indicate a higher likelihood of success following a vaso-epididymal anastomosis for idiopathic obstruction. However, these parameters are not

  18. Posterior muscolofascial reconstruction incorporated into urethrovescical anastomosis during robot-assisted radical prostatectomy.

    Science.gov (United States)

    Ficarra, Vincenzo; Gan, Melanie; Borghesi, Marco; Zattoni, Fabio; Mottrie, Alexandre

    2012-12-01

    The rationale of posterior musculofascial plate reconstruction during radical prostatectomy is to shorten the time to reach urinary continence recovery and to reduce the risk of bleeding and anastomosis leakage. We describe our original technique incorporating the posterior muscolofascial reconstruction into urethrovesical anastomosis using robot-assisted radical prostatectomy (RARP). For this reconstructive step, we use a 30-cm V-Loc 90 3-0 barbed suture (V-20 tapered needle). Specifically, the free edge of the posterior layer of the Denonvilliers fascia is approximated to the posterior part of the sphincteric apparatus in a running fashion from left to right. The musculature of the urethral wall is incorporated in this first layer of the running suture. This suture is then continued back to the left in a second layer incorporating the anterior layer of the Denonvilliers fascia (or prostatovesical muscle), the bladder neck, and again the urethra, this time also with urethral mucosa. The urethrovesical anastomosis is completed using a second running barbed suture (15-cm V-Loc 90 3-0 barbed suture, V-20 tapered needle). No intraoperative complications were observed during this step of the procedure. Anastomotic leakages were observed only in 2% of cases. Only 12.5% showed urinary incontinence after catheter removal (1-2 pads). At mean follow-up of 9 months, the urinary continence recovery was 95%, and an anastomosis stricture necessitating an endoscopic incision developed in only three (1.5%) patients. Recent systematic reviews of the literature showed only a minimal advantage in favor of posterior musculofascial reconstruction in terms of urinary continence recovery within 1 month after radical prostatectomy. We support the use of this step of RARP because it is simple, reproducible, with a very limited increase in operative time, and with only a slight risk of potential harm to the patient. Moreover, it could improve hemostasis and provide greater support for a

  19. Increased collagen maturity with sildenafil citrate: experimental high risk colonic anastomosis model.

    Science.gov (United States)

    Cakir, Tebessum; Ozer, Ilter; Bostanci, Erdal Birol; Keklik, Tulay Timucin; Ercin, Ugur; Bilgihan, Ayse; Akoglu, Musa

    2015-01-01

    Inadequate healing and high anastomosis leak rates at rectal anastomosis may be due to lack of supportive serosal layer and technical difficulty of low anterior resections. Positive effects of sildenafil on wound healing were observed. The aim of this study was to simulate rectal anastomosis as a technical insufficient anastomosis and investigate the effects of sildenafil on anastomosis healing. Colonic anastomoses were carried out in 64 rats and randomized into four groups, CA-S, complete anastomoses without sildenafil (10 mg/kg for 5 days); CA+S, complete anastomoses with sildenafil; IA-S, incomplete anastomoses without sildenafil; IA+S, incomplete anastomoses with sildenafil. Half of the rats in every group were sacrificed on post-operative day (POD) 3, half of them sacrificed on POD 7. Tissues from the anastomoses were used for functional, histochemical, biochemical investigations. Sildenafil treatment resulted in increased bursting pressures in IA+S on POD 7 (p=0.010). Collagen maturity was higher in IA+S on POD 3 and POD 7, CA+S on POD 7 (p=0.010; p=0.010; p<0.007). Collagen content was higher in IA+S on POD 7 (p<0.001). Glutathione, hydroxyproline levels were similar. Malondialdehyde levels were lower in IA+S on POD 3 (p<0.001). Epithelization score was higher in IA+S on POD 7 (p=0.007). Inflammation score was higher in CA-S group on POD 3 and POD 7 (p<0.001; p<0.001). Neutrophil score was lower in CA+S on POD 3 (p=0.005). An increase in collagen content, maturity, and epithelization, a decrease in neutrophil infiltration, oxidative stress and better mechanical strength were observed with the administration of sildenafil. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Does hyperbaric oxygen therapy reduce the effects of ischemia on colonic anastomosis in laparoscopic colon resection?

    Science.gov (United States)

    Emir, Seyfi; Gurdal, Sibel Ozkan; Sozen, Selim; Bali, Ilhan; Yesildag, Ebru; Celik, Atilla; Guzel, Savas; Sahin, Onder; Ay, Hakan; Topcu, Birol

    2016-01-01

    An increase in intra-abdominal pressure causes a decrease in the splanchnic blood flow and the intramucosal pH of the bowel, as well as increasing the risk of ischemia in the colon. The aim of the present study is to evaluate the effect of hyperbaric oxygen therapy (HBOT) on the ischemia caused by laparoscopy in colonic anastomosis in an experimental model of laparoscopic colonic surgery. We divided 30 male Wistar albino rats into three groups: Group A was the control (open colon anastomosis); Group B received LCA (laparoscopic colon anastomosis); while Group C received both LCA and HBOT. Each group contained ten animals. We placed Group C (LCA and HBOT) in an experimental hyperbaric chamber into which we administered pure oxygen at 2.1 atmospheres absolute 100% oxygen for 60 min for ten consecutive days. The anastomotic bursting pressure value was found to be higher in the open surgery group (226 ± 8.8) (Group A). The result for Group C (213 ± 27), which received HBOT, was better than that for Group B (197 ± 27). However, there was no statistically significant difference between Group B and Group C. Group A showed better healing than the other groups, while significant differences in the fibroblast proliferation scores were found between Groups A and B. In terms of tissue hydroxyproline levels, a significant difference was found between Groups A and B and between Groups A and C, but not between Groups B and C. HBOT increases the oxygen level in the injured tissue. Although HBOT might offer several advantages, it had only a limited effect on the healing of colonic anastomosis in rats with increased intra-abdominal pressure in our study. Anastomosis, Colon, Hyperbaric Oxygen Treatment, Oxidative Stress.

  1. Method for obtaining large levitation pressure in superconducting magnetic bearings

    Science.gov (United States)

    Hull, John R.

    1996-01-01

    A method and apparatus for compressing magnetic flux to achieve high levitation pressures. Magnetic flux produced by a magnetic flux source travels through a gap between two high temperature superconducting material structures. The gap has a varying cross-sectional area to compress the magnetic flux, providing an increased magnetic field and correspondingly increased levitation force in the gap.

  2. Electromotive force in strongly compressible magnetohydrodynamic turbulence

    Science.gov (United States)

    Yokoi, N.

    2017-12-01

    Variable density fluid turbulence is ubiquitous in geo-fluids, not to mention in astrophysics. Depending on the source of density variation, variable density fluid turbulence may be divided into two categories: the weak compressible (entropy mode) turbulence for slow flow and the strong compressible (acoustic mode) turbulence for fast flow. In the strong compressible turbulence, the pressure fluctuation induces a strong density fluctuation ρ ', which is represented by the density variance ( denotes the ensemble average). The turbulent effect on the large-scale magnetic-field B induction is represented by the turbulent electromotive force (EMF) (u': velocity fluctuation, b': magnetic-field fluctuation). In the usual treatment in the dynamo theory, the expression for the EMF has been obtained in the framework of incompressible or weak compressible turbulence, where only the variation of the mean density , if any, is taken into account. We see from the equation of the density fluctuation ρ', the density variance is generated by the large mean density variation ∂ coupled with the turbulent mass flux . This means that in the region where the mean density steeply changes, the density variance effect becomes relevant for the magnetic field evolution. This situation is typically the case for phenomena associated with shocks and compositional discontinuities. With the aid of the analytical theory of inhomogeneous compressible magnetohydrodynamic (MHD) turbulence, the expression for the turbulent electromotive force is investigated. It is shown that, among others, an obliqueness (misalignment) between the mean density gradient ∂ and the mean magnetic field B may contribute to the EMF as ≈χ B×∂ with the turbulent transport coefficient χ proportional to the density variance (χ ). This density variance effect is expected to strongly affect the EMF near the interface, and changes the transport properties of turbulence. In the case of an interface under the MHD slow

  3. Identification of Spanish isolates of Rhizoctonia solani from potato by anastomosis grouping, ITS-RFLP and RAMS-fingerprinting

    Directory of Open Access Journals (Sweden)

    A.M. Elbakali

    2003-08-01

    Full Text Available Anastomosis grouping, restriction fragment length polymorphism (RFLP of the ITS regions including the 5.85 rDNA, and random amplified microsatellites (RAMS were used to characterize isolates of Rhizoctonia solani collected from Spain and Finland. There was a high similarity between the results obtained with the three techniques. RAMS markers revealed more genetic variation among isolates of R. solani than RFLP. The anastomosis group (AG–3 isolates were clearly separated from isolates belonging to other AGs by RAMS, RFLPs and anastomosis grouping. Almost all the isolates sampled from potato belonged to AG–3. No differences were observed between Spanish and Finnish AG–3 isolates.

  4. Posterior leukoencephalopathy following repair of an ileocecal anastomosis breakdown: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Kasper Ekkehard M

    2011-01-01

    Full Text Available Abstract Introduction Posterior reversible leukoencephalopathy syndrome refers to a constellation of neurologic symptoms related to temporary white matter changes. The disease typically presents in the context of an abrupt and drastic elevation in blood pressure (>180/110 mmHg. We report an unusual case of posterior reversible leukoencephalopathy syndrome in a post-operative setting, with a blood pressure parameter generally tolerated by most patients. Case presentation We report the case of a 22-year-old Caucasian man who suffered acute onset visual acuity loss four days after an ileocecal anastomosis. A head magnetic resonance imaging scan revealed findings typically associated with posterior reversible leukoencephalopathy syndrome. His symptoms developed in the context of blood pressure parameters that are typically well tolerated in a post-operative setting (150-160/80-90 mmHg. He did not have a history of renal failure or immunosuppression. His symptoms resolved with aggressive blood pressure management. Conclusions Posterior reversible leukoencephalopathy syndrome can occur in a post-operative setting with blood pressure parameters typically well-tolerated in most post-surgical patients. Timely diagnosis and treatment will minimize the risk of permanent neurologic injury.

  5. Compressed sensing & sparse filtering

    CERN Document Server

    Carmi, Avishy Y; Godsill, Simon J

    2013-01-01

    This book is aimed at presenting concepts, methods and algorithms ableto cope with undersampled and limited data. One such trend that recently gained popularity and to some extent revolutionised signal processing is compressed sensing. Compressed sensing builds upon the observation that many signals in nature are nearly sparse (or compressible, as they are normally referred to) in some domain, and consequently they can be reconstructed to within high accuracy from far fewer observations than traditionally held to be necessary. Apart from compressed sensing this book contains other related app

  6. Compact toroid formation, compression, and acceleration

    International Nuclear Information System (INIS)

    Degnan, J.H.; Peterkin, R.E. Jr.; Baca, G.P.; Beason, J.D.; Bell, D.E.; Dearborn, M.E.; Dietz, D.; Douglas, M.R.; Englert, S.E.; Englert, T.J.; Hackett, K.E.; Holmes, J.H.; Hussey, T.W.; Kiuttu, G.F.; Lehr, F.M.; Marklin, G.J.; Mullins, B.W.; Price, D.W.; Roderick, N.F.; Ruden, E.L.; Sovinec, C.R.; Turchi, P.J.; Bird, G.; Coffey, S.K.; Seiler, S.W.; Chen, Y.G.; Gale, D.; Graham, J.D.; Scott, M.; Sommars, W.

    1993-01-01

    Research on forming, compressing, and accelerating milligram-range compact toroids using a meter diameter, two-stage, puffed gas, magnetic field embedded coaxial plasma gun is described. The compact toroids that are studied are similar to spheromaks, but they are threaded by an inner conductor. This research effort, named MARAUDER (Magnetically Accelerated Ring to Achieve Ultra-high Directed Energy and Radiation), is not a magnetic confinement fusion program like most spheromak efforts. Rather, the ultimate goal of the present program is to compress toroids to high mass density and magnetic field intensity, and to accelerate the toroids to high speed. There are a variety of applications for compressed, accelerated toroids including fast opening switches, x-radiation production, radio frequency (rf) compression, as well as charge-neutral ion beam and inertial confinement fusion studies. Experiments performed to date to form and accelerate toroids have been diagnosed with magnetic probe arrays, laser interferometry, time and space resolved optical spectroscopy, and fast photography. Parts of the experiment have been designed by, and experimental results are interpreted with, the help of two-dimensional (2-D), time-dependent magnetohydrodynamic (MHD) numerical simulations. When not driven by a second discharge, the toroids relax to a Woltjer--Taylor equilibrium state that compares favorably to the results of 2-D equilibrium calculations and to 2-D time-dependent MHD simulations. Current, voltage, and magnetic probe data from toroids that are driven by an acceleration discharge are compared to 2-D MHD and to circuit solver/slug model predictions. Results suggest that compact toroids are formed in 7--15 μsec, and can be accelerated intact with material species the same as injected gas species and entrained mass ≥1/2 the injected mass

  7. Bunch compression for an FEL at NLCTA

    International Nuclear Information System (INIS)

    Zimmermann, F.

    1997-04-01

    As part of the design effort for a free electron laser driven by the Next Linear Collider Test Accelerator (NLCTA), the author reports studies of bunch-length compression utilizing the existing infrastructure and hardware. In one possible version of the NLCTA FEL, bunches with 900-microm FWHM length, generated by an S-band photo-injector, would be compressed to an rms length of 60--120 microm before entering the FEL undulator. It is shown that, using the present magnetic chicane, the bunch compression is essentially straightforward, and that almost all emittance-diluting effects, e.g. wakefields, chromaticity, or space charge in the bending magnets, are small. The only exception to this finding is the predicted increase of the horizontal emittance due to coherent synchrotron radiation (CSR). Estimates based on existing theories of coherent synchrotron radiation suggest a tripling or quadrupling of the initial emittance, which seems to preclude bunch compression during regular FEL operation. Serendipitously, the magnitude of the predicted emittance growth would, on the other hand, make the NLCTA chicane an excellent tool for measuring the effects of coherent synchrotron radiation. This will be of considerable interest to many future projects, in particular to the Linac Coherent Light Source (LCLS). As an aside, it is shown that coherent synchrotron radiation in a bending magnet gives rise to a minimum possible bunch length, which is very reminiscent of the Oide limit on the vertical spot size at the interaction point of a linear collider

  8. Effect of Ozone Therapy (OT on Healing of Colonic Anastomosis in a Rat Model of Peritonitis

    Directory of Open Access Journals (Sweden)

    Başak Erginel

    2014-09-01

    Full Text Available Background: Ozone is a three-oxygen molecule (O3. Ozone therapy (OT is systematically effective when pathological inflammatory and immunologic processes are activated. Among of these conditions are wound healing, macular degeneration related to aging, and conditions that are ischemic or infectious. Aims: The aim of this study was to determine the effects of OT on wound healing of intestinal anastomosis in the presence of peritonitis in a rat model. Study Design: Animal experimentation. Methods: A total of 40 Wistar albino rats were randomized into four groups (n=10 including: sham (S, peritonitis (P, ozone 0 (O0, and ozone 24 (O24. In group S, only cecal dissection was carried out. The S group had only a cecal dissection and intestinal anastomosis performed, but no peritonitis. In all other groups, cecal ligation and puncture (CLP followed the cecal dissection to induce bacterial peritonitis. 24 h after puncture, a cecal resection and ileocolic anastomosis were performed. In group P, 24 h after CLP, a cecal resection and ileocolic anastomosis were performed and no ozone was administered. In group O0, immediately after the anastomosis, and in group O24, starting 24 hours after the anastomosis, an intraperitoneal 1 mg/kg/day ozone administration was applied for seven days. On the seventh day the animals were sacrificed, the anastomotic bursting pressures (BP and the hydroxyproline values of the anastomotic tissues were measured, and histopathologic examination of the anastomotic segment was carried out. Results: The highest BP was in group S, with 211±23.13 mmHg. The mean BP of group P was 141±56.25 mmHg, which was significantly lower than in the other two peritonitis groups that received ozone therapy, group O0 and O24, where it was 192±22 and 166±45 mmHg, respectively (p0.05. Histopathologic analyses of the anastomotic segments determined there was significantly more oedema and necrosis in the control group rats, and collagen deposition in

  9. Ohmic ignition of Neo-Alcator tokamak with adiabatic compression

    International Nuclear Information System (INIS)

    Inoue, Nobuyuki; Ogawa, Yuichi

    1992-01-01

    Ohmic ignition condition on axis of the DT tokamak plasma heated by minor radius and major radius adiabatic compression is studied assuming parabolic profiles for plasma parameters, elliptic plasma cross section, and Neo-Alcator confinement scaling. It is noticeable that magnetic compression reduces the necessary total plasma current for Ohmic ignition device. Typically in compact ignition tokamak of the minor radius of 0.47 m, major radius of 1.5 m and on-axis toroidal field of 20 T, the plasma current of 6.8 MA is sufficient for compression plasma, while that of 11.7 MA is for no compression plasma. Another example with larger major radius is also described. In such a device the large flux swing of Ohmic transformer is available for long burn. Application of magnetic compression saves the flux swing and thereby extends the burn time. (author)

  10. Endoscopic magnetic gastroenteric anastomosis for palliation of malignant gastric outlet obstruction: a prospective multicenter study

    NARCIS (Netherlands)

    van Hooft, Jeanin E.; Vleggaar, Frank P.; Moine, Olivier Le; Bizzotto, Alessandra; Voermans, Rogier P.; Costamagna, Guido; Devière, Jacques; Siersema, Peter D.; Fockens, Paul

    2010-01-01

    Background: Palliation of malignant gastric outlet obstruction remains challenging. Although there are 2 established treatment options, ie, surgical gastrojejunostomy and endoscopic duodenal stent insertion, there is an ongoing search for a technique that would combine the safety and rapid effect of

  11. Bunch Compression Stability Dependence on RF Parameters

    CERN Document Server

    Limberg, T

    2005-01-01

    In present designs for FEL's with high electron peak currents and short bunch lengths, higher harmonic RF systems are often used to optimize the final longitudinal charge distributions. This opens degrees of freedom for the choice of RF phases and amplitudes to achieve the necessary peak current with a reasonable longitudinal bunch shape. It had been found empirically that different working points result in different tolerances for phases and amplitudes. We give an analytical expression for the sensitivity of the compression factor on phase and amplitude jitter for a bunch compression scheme involving two RF systems and two magnetic chicanes as well numerical results for the case of the European XFEL.

  12. Central arteriovenous anastomosis for the treatment of patients with uncontrolled hypertension (the ROX CONTROL HTN study): a randomised controlled trial.

    LENUS (Irish Health Repository)

    Lobo, Melvin D

    2015-01-22

    Hypertension contributes to cardiovascular morbidity and mortality. We assessed the safety and efficacy of a central iliac arteriovenous anastomosis to alter the mechanical arterial properties and reduce blood pressure in patients with uncontrolled hypertension.

  13. Anisotropic Concrete Compressive Strength

    DEFF Research Database (Denmark)

    Gustenhoff Hansen, Søren; Jørgensen, Henrik Brøner; Hoang, Linh Cao

    2017-01-01

    When the load carrying capacity of existing concrete structures is (re-)assessed it is often based on compressive strength of cores drilled out from the structure. Existing studies show that the core compressive strength is anisotropic; i.e. it depends on whether the cores are drilled parallel...

  14. Experiments with automata compression

    NARCIS (Netherlands)

    Daciuk, J.; Yu, S; Daley, M; Eramian, M G

    2001-01-01

    Several compression methods of finite-state automata are presented and evaluated. Most compression methods used here are already described in the literature. However, their impact on the size of automata has not been described yet. We fill that gap, presenting results of experiments carried out on

  15. Comparison between double-balloon and single-balloon enteroscopy in therapeutic ERC after Roux-en-Y entero-enteric anastomosis.

    Science.gov (United States)

    Moreels, Tom G; Pelckmans, Paul A

    2010-09-16

    To compare the efficacy of double-balloon enteroscopy (DBE) and single-balloon enteroscopy (SBE) in therapeutic endoscopic retrograde cholangiography (ERC) in patients with Roux-en-Y entero-enteric anastomosis. Retrospective analysis of our patient cohort revealed 4 patients with enterobiliary anastomosis and Roux-en-Y entero-enteric anastomosis who underwent repeated ERC with DBE and SBE because of recurrent cholangitis. A total of 38 endoscopic retrograde cholangiopancreatography procedures were performed in 25 patients with Roux-en-Y entero-enteric anastomosis. DBE was used in 29 procedures and SBE in 9. The 4 patients who underwent repeated ERC with DBE and SBE suffered from recurrent cholangitis due to stenosis of the enterobiliary anastomosis. ERC was performed repeatedly to achieve balloon dilation with/without biliary stone extraction and multiple stent placement at the level of the enterobiliary anastomosis. In all 4 patients DBE and SBE were equally successful. Compared to DBE, SBE was equally effective in passing the Roux-en-Y entero-enteric anastomosis, reaching the enterobiliary anastomosis and performing therapeutic ERC. This retrospective comparison shows that DBE and SBE are equally successful in the performance of therapeutic ERC at the level of the enterobiliary anastomosis after Roux-en-Y entero-enteric anastomosis.

  16. Laparoscopic Low Anterior Resection and Eversion Technique Combined With a Nondog Ear Anastomosis for Mid- and Distal Rectal Neoplasms

    OpenAIRE

    Zhuo, Changhua; Liang, Lei; Ying, Mingang; Li, Qingguo; Li, Dawei; Li, Yiwei; Peng, Junjie; Huang, Liyong; Cai, Sanjun; Li, Xinxiang

    2015-01-01

    Abstract The transanal eversion and prolapsing technique is a well-established procedure, and can ensure an adequate distal margin for patients with low rectal neoplasms. Potential leakage risks, however, are associated with bilateral dog ear formation, which results from traditional double-stapling anastomosis. The authors determined the feasibility of combining these techniques with a commercial stapling set to achieve a nondog ear (end-to-end) anastomosis for patients with mid- and distal ...

  17. Moist-condition Training for Cerebrovascular Anastomosis: A Practical Step after Mastering Basic Manipulations.

    Science.gov (United States)

    Shimizu, Satoru; Sekiguchi, Tomoko; Mochizuki, Takahiro; Sato, Kimitoshi; Koizumi, Hiroyuki; Nakayama, Kenji; Yamamoto, Isao; Kumabe, Toshihiro

    2015-01-01

    As cerebrovascular anastomosis is performed in moist conditions that may impede precise manipulations, surgeons must undergo extensive preoperative training. We developed a simple moist-condition training method. It involves placing a free-floating inner platform hosting an artery from a chicken wing in an outer container filled with tap water to just below the specimen. Trainees performed anastomosis under magnification. Training sessions mimicked difficulties encountered during operations such as poor visibility of the lumen and problems handling the sutures. A retrospective comparison of 100 wet- and 100 dry-condition training sessions for end-to-side anastomoses with 8 stitches showed that under moist condition the time required for the entire procedure was significantly longer (17.8 ± 2.1 vs. 15.3 ± 2.1 min, p bridge between training for basic manipulations under dry conditions and actual surgery.

  18. Laparoscopic subtotal colectomy with transrectal extraction of the colon and ileorectal anastomosis.

    Science.gov (United States)

    Awad, Ziad T

    2012-03-01

    Despite the growing acceptance of laparoscopic colon surgery, an abdominal incision is needed to remove the specimen and perform an anastomosis. Five trocars (one 12 mm and four 5 mm) were used. The video describes the technique of performing laparoscopic subtotal colectomy, laparoscopic cholecystectomy, transrectal removal of the gallbladder and the entire colon, and intracorporeal stapled ileorectal anastomosis in a 27-year-old female with colonic inertia and biliary dyskinesia. There were no intraoperative complications. The operating time was 180 min. Blood loss was 10 cc. The patient was discharged home on postoperative day 4. Laparoscopic subtotal colectomy with transrectal removal of the colon is a safe and effective procedure that can be added to the armamentarium of surgeons performing laparoscopic colon surgery. This technique may provide both an attractive way to reduce abdominal wall morbidity and a bridge to NOTES colon surgery.

  19. Abdominoendorectal resection with peranal anastomosis in the treatment of radiation injuries of the rectum

    Energy Technology Data Exchange (ETDEWEB)

    Athanasiadis, S.; Girona, J.

    1982-01-01

    During the period 1974-1980 39 patients underwent operations at the Prosper Hospital in Recklinghausen for radiation injuries to the rectum or rectosigmoid. They comprised 22 patients with rectovaginal fistulas, 6 with ulcers, 3 suffering from severe hemorrhagic proctitis, 5 with rectal strictures, 1 with necrosis, and 2 with radiation ulcers and carcinoma. A sphincter-saving operative method of treating postirradiation damage of the rectum is presented. The technique involves the peranal anastomosis of healthy colon to the midanal canal using a sleeve anastomosis. Technical and functional results of resectional surgery for the rectal complications of radiation therapy are reported. Subjectively, total continence was present in 78%, only 1 patient was incontinent because of flatus and watery stools.

  20. Measurement of blood flow through surgical anastomosis using the radioactive microsphere technique

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, S.J.; Delgado, G.; Butterfield, A.; Dritschilo, A.; Harbert, J.

    1985-10-01

    Two different radioactive microspheres ( U Ce and UWSc) were used to measure blood flow to an area of the large intestine in dogs before and after a surgical resection was performed with surgical staples. The healing of an anastomosis is theoretically related to the blood flow to the anastomotic site. Blood flow studies were conducted in three dogs using this technique. The average blood flow preoperatively was 0.558 mL/minute per gram and 1.04 mL/minute per gram postoperatively. These results indicate a statistically significant increase in blood flow at the anastomotic site six days after anastomosis when compared with the blood flow to the same area before any surgical procedures.

  1. Measurement of blood flow through surgical anastomosis using the radioactive microsphere technique

    International Nuclear Information System (INIS)

    Hummel, S.J.; Delgado, G.; Butterfield, A.; Dritschilo, A.; Harbert, J.

    1985-01-01

    Two different radioactive microspheres ( 141 Ce and 46 Sc) were used to measure blood flow to an area of the large intestine in dogs before and after a surgical resection was performed with surgical staples. The healing of an anastomosis is theoretically related to the blood flow to the anastomotic site. Blood flow studies were conducted in three dogs using this technique. The average blood flow preoperatively was 0.558 mL/minute per gram and 1.04 mL/minute per gram postoperatively. These results indicate a statistically significant increase in blood flow at the anastomotic site six days after anastomosis when compared with the blood flow to the same area before any surgical procedures

  2. The abdominoendorectal resection with peranal anastomosis in the treatment of radiation injuries of the rectum

    International Nuclear Information System (INIS)

    Athanasiadis, S.; Girona, J.

    1982-01-01

    During the period 1974-1980 39 patients underwent operations at the Prosper Hospital in Recklinghausen for radiation injuries to the rectum or rectosigmoid. They comprised 22 patients with rectovaginal fistulas, 6 with ulcers, 3 suffering from severe hemorrhagic proctitis, 5 with rectal strictures, 1 with necrosis, and 2 with radiation ulcers and carcinoma. A sphincter-saving operative method of treating postirradiation damage of the rectum is presented. The technique involves the peranal anastomosis of healthy colon to the midanal canal using a sleeve anastomosis. Technical and functional results of resectional surgery for the rectal complications of radiation therapy are reported. Subjectively, total continence was present in 78%, only 1 patient was incontinent because of flatus and watery stools. (orig.) [de

  3. Transvaginal coloanal anastomosis after rectal resection for the treatment of a rectovaginal fistula induced by radiation.

    Science.gov (United States)

    Brezean, I

    2014-01-01

    Although decreasing in number, radiation induced rectovaginal fistulas are caused by some radiation injuries and chronic ischemic lesions. Most of the experienced authors recommend anterior rectal resection with coloanal anastomosis accessed through the abdominal-perineum area for high fistula. We present a patient with a fistula that developed 23 years after hysterectomy and radiotherapy. In this case we performed an abdominal-transvaginal rectal resection with transverse coloplastypouch, coloanal anastomosis and protection ileostomy three months after a terminal sigmoidostomy. The dissection of the distal rectum by posteriour colpotomy and coloanal transvaginalan astomosis is a technical variant that may prove advantage ous compared to the procedures featured in the literature as solutions by rectal resection for rectovaginal fistula. Celsius.

  4. Colovaginal anastomosis: an unusual complication of stapler use in restorative procedure after Hartmann operation

    Directory of Open Access Journals (Sweden)

    Liao Guoqing

    2005-11-01

    Full Text Available Abstract Background Rectovaginal fistula is uncommon after lower anterior resection for rectal cancer. The most leading cause of this complication is involvement of the posterior wall of the vagina into the staple line when firing the circular stapler. Case presentation A 50-year-old women underwent resection for obstructed carcinoma of the sigmoid colon with Hartmann procedure. Four months later she underwent restorative surgery with circular stapler. Following which she developed rectovaginal fistula. A transvaginal repair was performed but stool passing from vagina not per rectum. Laporotomy revealed colovaginal anastomosis, which was corrected accordingly. Patient had an uneventful recovery. Conclusion Inadvertent formation of colovaginal anastomosis associated with a rectovaginal fistula is a rare complication caused by the operator's error. The present case again highlights the importance of ensuring that the posterior wall of vagina is away from the staple line.

  5. Fingertip replantation at the eponychial level with venous anastomosis: an anatomic study and clinical application.

    Science.gov (United States)

    Cheng, L; Chen, K; Chai, Y-M; Wen, G; Wang, C-Y

    2013-11-01

    We present an anatomic study of the vein distribution at the eponychial level, in order to standardize outpatient fingertip replantation. The cross sectional anatomy of 100 fingers was studied by dissection following dye injection. The distribution of the veins >0.3 mm was recorded on a pie-chart. Thirty fingers in 27 patients with fingertip amputations at the eponychial level were replanted by anastomosis of the palmar subcutaneous veins, to reconstruct the venous reflux of the amputated digits. The operations were aided by the anatomical study and confirmed that the palmar area is the preferred site for venous anastomosis Following a distal finger amputation at the level of the eponychial fold we propose starting the search for veins between the 3 to 5 o'clock or 7 to 9 o'clock positions, as these are the areas where there are most likely to be suitable veins.

  6. Laparoscopic restorative proctocolectomy ileal pouch anal anastomosis: How I do it?

    Directory of Open Access Journals (Sweden)

    Manish A Madnani

    2015-01-01

    Full Text Available Surgery for ulcerative colitis is a major and complex colorectal surgery. Laparoscopy benefits these patients with better outcomes in context of cosmesis, pain and early recovery, especially in young patients. For surgeons, it is a better tool for improving vision and magnification in deep cavities. This is not the simple extension of the laparoscopy training. Starting from preoperative preparation to post operative care there are wide variations as compared to open surgery. There are also many variations in steps of laparoscopic surgery. It involves left colon, right colon and rectal mobilisation, low division of rectum, pouch creation and anastomosis of pouch to rectum. Over many years after standardisation of this technique, it takes same operative time as open surgery at our centre. So we present our standardized technique of laparoscopic assisted restorative proctocolectomy and ileal pouch anal anastomosis (IPAA.

  7. Single-incision, laparoscopic-assisted jejunal resection and anastomosis following a gunshot wound.

    Science.gov (United States)

    Rubin, Jacob A; Shigemoto, Reynsen; Reese, David J; Case, J Brad

    2015-01-01

    A 2 yr old castrated male Pomeranian was evaluated for a 6 wk history of chronic vomiting, intermittent anorexia, and lethargy. Physical examination revealed a palpable, nonpainful, soft-tissue mass in the midabdominal area. Abdominal radiographs and ultrasound revealed a focal, eccentric thickening of the jejunal wall with associated jejunal mural foreign body and partial mechanical obstruction. Following diagnosis of a partial intestinal obstruction as the cause of chronic vomiting, the patient underwent general anesthesia for a laparoscopic-assisted, midjejunal resection and anastomosis using a single-incision laparoscopic surgery port. The patient was discharged the day after surgery, and clinical signs abated according to information obtained during a telephone interview conducted 2 and 8 wk postoperatively. The dog described in this report is a unique case of partial intestinal obstruction treated by laparoscopic-assisted resection and anastomosis using a single-incision laparoscopic surgery port.

  8. A meta-analysis of aneurysm formation in laser assisted vascular anastomosis (LAVA)

    Science.gov (United States)

    Chen, Chen; Peng, Fei; Xu, Dahai; Cheng, Qinghua

    2009-08-01

    Laser assisted vascular anastomosis (LAVA) is looked as a particularly promising non-suture method in future. However, aneurysm formation is one of the main reasons delay the clinical application of LAVA. Some scientists investigated the incidence of aneurysms in animal model. To systematically analyze the literature on reported incidence of aneurysm formation in LAVA therapy, we performed a meta-analysis comparing LAVA with conventional suture anastomosis (CSA) in animal model. Data were systematically retrieved and selected from PUBMED. In total, 23 studies were retrieved. 18 studies were excluded, and 5 studies involving 647 animals were included. Analysis suggested no statistically significant difference between LAVA and CSA (OR 1.24, 95%CI 0.66-2.32, P=0.51). Result of meta analysis shows that the technology of LAVA is very close to clinical application.

  9. Does the Ventrica magnetic vascular positioner (MVP) for coronary artery bypass grafting significantly alter local fluid dynamics? A numeric study.

    Science.gov (United States)

    Morbiducci, U; Lemma, M; Ponzini, R; Boi, A; Bondavalli, L; Antona, C; Montevecchi, F M; Redaelli, A

    2007-07-01

    Automatic devices have been recently introduced to make the anastomosis procedure quick and efficient when creating a coronary bypass on the beating heart. However, the implantation of these devices could modify the graft configuration, consistently affecting the hemodynamics usually found in the traditional anastomosis. As local fluid dynamics could play a significant role in the onset of vessel wall pathologies, in this article a computational approach was designed to investigate flow patterns in the presence of the Ventrica magnetic vascular positioner (Ventrica MVP) device. A model of standard hand-sewn anastomosis and of automated magnetic anastomosis were constructed, and the finite volume method was used to simulate in silico realistic graft hemodynamics. Synthetic analytical descriptors -- i.e., time-averaged wall shear stress (TAWSS), oscillating shear index (OSI) and helical flow index (HFI) -- were calculated and compared for quantitative assessment of the anastomosis geometry hemodynamic performance. In this case study, the same most critical region was identified for the 2 models as the one with the lowest TAWSS and the highest OSI (TAWSS=0.229, OSI=0.255 for the hand-sewn anastomosis; TAWSS=0.297, OSI=0.171 for the Ventrica MVP(R)). However, the shape of the Ventrica MVP does not induce more critical wall shear stresses, oscillating flow and damped helicity in the graft fluid dynamics, as compared with conventional anastomosis. We found that the use of the Ventrica MVP for the case study under investigation was not associated with more critical fluid dynamics than with conventional hand-sewn anastomosis. Thereby, the device could facilitate beating heart and minimally invasive coronary artery bypass grafting without increasing local hemodynamic-related risks of failure.

  10. Eversion Bile Duct Anastomosis: A Safe Alternative for Bile Duct Size Discrepancy in Deceased Donor Liver Transplantation.

    Science.gov (United States)

    Leal-Leyte, Pilar; McKenna, Greg J; Ruiz, Richard M; Anthony, Tiffany L; Saracino, Giovanna; Giuliano, Testa; Klintmalm, Goran B; Kim, Peter Tw

    2018-04-10

    Introduction Bile duct size discrepancy in liver transplantation may increase the risk of biliary complications. The aim of this study was to evaluate the safety and outcomes of the eversion bile duct anastomosis technique in deceased donor liver transplantation (DDLT) with duct to duct anastomosis. Methods A total of 210 patients who received a DDLT with duct to duct anastomosis from 2012 to 2017 were divided into two groups: those who had eversion bile duct anastomosis (N=70) and standard bile duct anastomosis (N=140). Biliary complications rates were compared between the two groups. Results There was no difference in the cumulative incidence of biliary strictures (P=0.20) and leaks (P=0.17) between the two groups. The biliary complication rate in the eversion group was 14.3% and 11.4% in the standard anastomosis group. All the biliary complications in the eversion group were managed with endoscopic stenting. A severe size mismatch (≥3:1 ratio) was associated with a significantly higher incidence of biliary strictures (44.4%) compared to 2:1 ratio (8.2%), (P=0.002). Conclusion The use of the eversion technique is a safe alternative for bile duct discrepancy in deceased donor liver transplantation; however, severe bile duct size mismatch may be a risk factor for biliary strictures with such technique. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

  11. Partial recovery of respiratory function and diaphragm reinnervation following unilateral vagus nerve to phrenic nerve anastomosis in rabbits.

    Directory of Open Access Journals (Sweden)

    Junxiang Wen

    Full Text Available Respiratory dysfunction is the leading cause of mortality following upper cervical spinal cord injury (SCI. Reinnervation of the paralyzed diaphragm via an anastomosis between phrenic nerve and a donor nerve is a potential strategy to mitigate ventilatory deficits. In this study, anastomosis of vagus nerve (VN to phrenic nerve (PN in rabbits was performed to assess the potential capacity of the VN to compensate for lost PN inputs. At first, we compared spontaneous discharge pattern, nerve thickness and number of motor fibers between these nerves. The PN exhibited a highly rhythmic discharge while the VN exhibited a variable frequency discharge pattern. The rabbit VN had fewer motor axons (105.3±12.1 vs. 268.1±15.4. Nerve conduction and respiratory function were measured 20 weeks after left PN transection with or without left VN-PN anastomosis. Compared to rabbits subjected to unilateral phrenicotomy without VN-PN anastomosis, diaphragm muscle action potential (AP amplitude was improved by 292%, distal latency by 695%, peak inspiratory flow (PIF by 22.6%, peak expiratory flow (PRF by 36.4%, and tidal volume by 21.8% in the anastomosis group. However, PIF recovery was only 28.0%, PEF 28.2%, and tidal volume 31.2% of Control. Our results suggested that VN-PN anastomosis is a promising therapeutic strategy for partial restoration of diaphragm reinnervation, but further modification and improvements are necessary to realize the full potential of this technique.

  12. Combined Tricuspid Valvuloplasty and Superior Cavopulmonary Anastomosis for Repair of Traumatic Tricuspid Valve Injury

    OpenAIRE

    Dimas, V. Vivian; Grifka, Ronald G.; Fraser, Charles D.

    2004-01-01

    Chronic tricuspid valve insufficiency secondary to blunt chest trauma is rare in the pediatric population, with fewer than 10 cases reported. Surgical repair has focused on the tricuspid valve. We present 2 cases of traumatic tricuspid valve insufficiency in pediatric patients after blunt chest trauma in whom tricuspid valve repair was performed along with superior cavopulmonary anastomosis. To our knowledge, this is the 1st report of the use of this combination of surgical procedures for rep...

  13. The Effects of Systemic IGF-I on the Arterial Anastomosis in Rats

    Directory of Open Access Journals (Sweden)

    Baris Keklik

    2014-04-01

    Full Text Available Objective: In this study, we aimed to document the effects of a well-known agent and mdash; and ldquo;insulin-like growth factor (IGF-I and rdquo; and mdash; on the microvascular anastomosis site. Methods: Sixteen Sprague-Dawley rats were used in this study. The rats were classified randomly into two equally numbered groups (eight rats each: the control (Group 1 and the experiment group (Group 2. The femoral artery was dissected completely in all rats. Following division of the artery, anastomoses were conducted with microvascular techniques. Forty-five minutes after the anastomoses, an Acland milking test was performed in order to check the patency and the first surgical session was terminated. In the second stage, LONG and reg; R3 IGF-I human (Sigma-Aldrich, St. Louis, Missouri, United States solution was introduced to Group 2 (experimental group intraperitoneally in doses of 2 mg/kg on the day of the surgery in addition to the third and seventh days postoperatively. On the 4th postoperative week, the patency of the anastomoses was evaluated with the Acland milking test. In addition, one centimeter of a vascular segment including the anastomosis site was excised and stained with hematoxylin-eosin. They were evaluated for edema, inflammation, vascular wall injury, intimal hyperplasia, medial atrophy, thrombus, calcification, foreign body reactions, and the endothelial proliferation. Results: The Acland milking test showed a 100% vascular patency in both groups. A statistically significant difference was found between the experimental and control groups in terms of edema and vascular wall injury (p0.05. Conclusion: Under the light of the obtained data, IGF-I was effective in preventing the edema and vascular wall injury at the anastomosis site. However, the net positive clinical effect on anastomosis patency necessitates further studies. [Arch Clin Exp Surg 2014; 3(2.000: 87-93

  14. Exteriorized colon anastomosis for unprepared bowel: An alternative to routine colostomy

    Science.gov (United States)

    Asfar, Sami K; Al-Sayer, Hilal M; Juma, Talib H

    2007-01-01

    AIM: To see the possibility of avoiding routine colostomy in patients presenting with unprepared bowel. METHODS: The cohort is composed of 103 patients, of these, 86 patients presented as emergencies (self-inflected and iatrogenic colon injuries, stab wounds and blast injury of the colon, volvulus sigmoid, obstructing left colon cancer, and strangulated ventral hernia). Another 17 patients were managed electively for other colon pathologies. During laparotomy, the involved segment was resected and the two ends of the colon were brought out via a separate colostomy wound. One layer of interrupted 3/0 silk was used for colon anastomosis. The exteriorized segment was immediately covered with a colostomy bag. Between the 5th and 7th postoperative day, the colon was easily dropped into the peritoneal cavity. The defect in the abdominal wall was closed with interrupted nonabsorbable suture. The skin was left open for secondary closure. RESULTS: The mean hospital stay (± SD) was 11.5 ± 2.6 d (8-20 d). The exteriorized colon was successfully dropped back into the peritoneal cavity in all patients except two. One developed a leak from oesophago-jejunostomy and from the exteriorized colon. She subsequently died of sepsis and multiple organ failure (MOF). In a second patient the colon proximal to the exteriorized anastomosis prolapsed and developed severe serositis, an elective ileo-colic anastomosis (to the left colon) was successfully performed. CONCLUSION: Exteriorized colon anastomosis is simple, avoids the inconvenience of colostomy and can be an alternative to routine colostomy. It is suitable where colostomy is socially unacceptable or the facilities and care is not available. PMID:17589900

  15. CLINICOPATHOLOGICAL STUDY AND MANAGEMENT OF LARGE GUT VOLVULUS WITH REFERENCE TO PRIMARY RESECTION AND ANASTOMOSIS

    Directory of Open Access Journals (Sweden)

    Siba Prasad Dash

    2017-11-01

    Full Text Available BACKGROUND Large gut volvulus is a common surgical emergency in many regions of the world with significant morbidity and mortality. Delay in the diagnosis and treatment can lead to serious complications such as like bowel gangrene, perforation, peritonitis and sepsis. Emergency operation is needed in acute large gut volvulus. The purpose of our study was to analyse the mode of presentations and evaluate the outcome of various methods used in surgical management with reference to primary resection and anastomosis of large gut volvulus, mainly sigmoid volvulus, as it is the commonest type encountered. MATERIALS AND METHODS This study was conducted in 52 patients with acute sigmoid volvulus randomly out of 214 cases of intestinal obstruction admitted to M.K.C.G. Medical College in the Department of General Surgery from July 2015 to June 2017. Laparotomy were carried out in all 52 patients, primary resection of the affected sigmoid colon with anastomosis in single layer (n=21 and double layer (n=31 were done. Outcome of the two procedures analysed in terms of mortality, postoperative complications and hospital stay. RESULTS The maximum number of cases were found in between 41 to 60 years of age and male-to-female ratio was 2.7:1. Distention of abdomen (96% followed by constipation in 90% were common mode of presentation. Postoperative mortality rate of 6%. Common postoperative complication found to be wound infections and a chest infection. It was 27% and 25%, respectively. Mortality and morbidity associated with single layer anastomosis was lower (14.29% compared with conventional double layer technique (22.58%. CONCLUSION This study demonstrated that resection and anastomosis should be done in acute sigmoid volvulus safely. Single layer extra mucosal technique is safe and desirable in clinical practice with significant advantages than standard two layer technique.

  16. [Abdominothoracic esophageal resection according to Ivor Lewis with intrathoracic anastomosis : standardized totally minimally invasive technique].

    Science.gov (United States)

    Runkel, N; Walz, M; Ketelhut, M

    2015-05-01

    The clinical and scientific interest in minimally invasive techniques for esophagectomy (MIE) are increasing; however, the intrathoracic esophagogastric anastomosis remains a surgical challenge and lacks standardization. Surgeons either transpose the anastomosis to the cervical region or perform hybrid thoracotomy for stapler access. This article reports technical details and early experiences with a completely laparoscopic-thoracoscopic approach for Ivor Lewis esophagectomy without additional thoracotomy. The extent of radical dissection follows clinical guidelines. Laparoscopy is performed with the patient in a beach chair position and thoracoscopy in a left lateral decubitus position using single lung ventilation. The anvil of the circular stapler is placed transorally into the esophageal stump. The specimen and gastric conduit are exteriorized through a subcostal rectus muscle split incision. The stapler body is placed into the gastric conduit and both are advanced through the abdominal mini-incision transhiatally into the right thoracic cavity, where the anastomosis is constructed. Data were collected prospectively and analyzed retrospectively. A total of 23 non-selected consecutive patients (mean age 69 years, range 46-80 years) with adenocarcinoma (n = 19) or squamous cell carcinoma (n = 4) were surgically treated between June 2010 and July 2013. Neoadjuvant therapy was performed in 15 patients resulting in 10 partial and 4 complete remissions. There were no technical complications and no conversions. Mean operative time was 305 min (range 220-441 min). The median lymph node count was 16 (range 4-42). An R0 resection was achieved in 91 % of patients and 3 anastomotic leaks occurred which were successfully managed endoscopically. There were no postoperative deaths. The intrathoracic esophagogastric anastomosis during minimally invasive Ivor Lewis esophagectomy can be constructed in a standardized fashion without an additional thoracotomy

  17. A Novel Technique for Duodenal Resection and Primary Anastomosis With Robotic Assistance and OrVil.

    Science.gov (United States)

    Bedirli, Abdulkadir; Salman, Bulent; Nasirov, Mahir; Dogan, Ibrahim

    2017-01-01

    Benign duodenal neoplasm is a rare occurrence. Minimally invasive tumor resection and anastomosis formation with an OrVil catheter is a novel approach to treating this disease. In this article, we present a new technique for duodenojejunal anastomosis. This technique was applied in 4 patients with benign distal duodenal tumors who were treated with minimally invasive surgery with robotic assistance. In 4 patients, after the removal of distal duodenal masses with a robotic technique, an orifice in the duodenum was opened to allow for the passage of a guidewire. The guidewire was removed from the orifice by holding it with forceps during an upper endoscopy. An OrVil catheter was sutured to the guidewire outside to allow 2 catheters to proceed consecutively. After the removal of the anvil, an end-lateral duodenojejunostomy was performed with a circular stapler. The patients included 3 men and 1 woman (average age, 56). The durations of the operations were 215, 175, 180, and 185 minutes. No complications were observed in any of the patients during the postoperative period. The patients began oral intake on the fifth day of the postoperative period, and they were discharged on the sixth postoperative day. Histopathologic analyses indicated that the removed tumors were adenomas in 2 patients and gastrointestinal stromal tumors (GISTs) in 2 patients. Clear surgical margins were observed in all of the patients. The placement of an OrVil catheter for anastomosis in benign neoplasms with distal duodenum localization and the subsequent achievement of duodenojejunal anastomosis with a circular stapler constitute a novel treatment approach.

  18. Effects of circular myotomy on the healing of esophageal suture anastomosis: an experimental study.

    Science.gov (United States)

    Tannuri, U; Tannuri, A C; Fukutaki, M F; de Oliveira, M S; Muoio, V M; Massaguer, A A

    1999-01-01

    For esophageal reconstruction in newborns with esophageal atresia, esophageal reunion with an end-to-end anastomosis is the ideal procedure, although it may result in leaks and strictures due to tension on the suture line, mainly in cases with a wide gap between the ends. Circular myotomy (Livaditis' procedure) is the best method to elongate the proximal esophageal pouch and reduce anastomotic tension. This experimental investigation in dogs was undertaken to attempt to verify that circular myotomy decreases the anastomotic leak rate in newborns with wide gap esophageal atresia, and to analyze whether the technique promotes morphologic changes in the anastomotic scar. A pilot study demonstrated that it is necessary to resect more than 8 cm (40% of the total esophageal length) in order to obtain high leak rates. In the experimental project, such resection was performed in dogs divided into two groups (control group, anastomosis only, and experimental group, anastomosis plus circular myotomy in the proximal esophageal segment). The animals were killed in the 14th postoperative day, submitted to autopsy, and were evaluated as to the presence of leaks and strictures, as well as to the features (macroscopic and microscopic aspects) of the anastomosis. Leak rates were the same in both groups. Morphometric analysis revealed that in animals in the experimental group, the anastomotic scar was thinner than the control animals, and the isolated muscular manchette distal to the site of myotomy was replaced by fibrous tissue. Correspondingly, a decreased number of newly formed small vessels were noted in the experimental animals, compared to control animals. We concluded that circular myotomy does not decrease the incidence of anastomotic leaks, and it also promotes deleterious changes in anastomotic healing.

  19. Effects of circular myotomy on the healing of esophageal suture anastomosis: an experimental study

    Directory of Open Access Journals (Sweden)

    Tannuri Uenis

    1999-01-01

    Full Text Available For esophageal reconstruction in newborns with esophageal atresia, esophageal reunion with an end-to-end anastomosis is the ideal procedure, although it may result in leaks and strictures due to tension on the suture line, mainly in cases with a wide gap between the ends. Circular myotomy (Livaditis' procedure is the best method to elongate the proximal esophageal pouch and reduce anastomotic tension. This experimental investigation in dogs was undertaken to attempt to verify that circular myotomy decreases the anastomotic leak rate in newborns with wide gap esophageal atresia, and to analyze whether the technique promotes morphologic changes in the anastomotic scar. A pilot study demonstrated that it is necessary to resect more than 8 cm (40% of the total esophageal length in order to obtain high leak rates. In the experimental project, such resection was performed in dogs divided into two groups (control group, anastomosis only, and experimental group, anastomosis plus circular myotomy in the proximal esophageal segment. The animals were killed in the 14th postoperative day, submitted to autopsy, and were evaluated as to the presence of leaks and strictures, as well as to the features (macroscopic and microscopic aspects of the anastomosis. Leak rates were the same in both groups. Morphometric analysis revealed that in animals in the experimental group, the anastomotic scar was thinner than the control animals, and the isolated muscular manchette distal to the site of myotomy was replaced by fibrous tissue. Correspondingly, a decreased number of newly formed small vessels were noted in the experimental animals, compared to control animals. We concluded that circular myotomy does not decrease the incidence of anastomotic leaks, and it also promotes deleterious changes in anastomotic healing.

  20. Use of atropine to reduce mucosal eversion during intestinal resection and anastomosis in the dog.

    Science.gov (United States)

    Agrodnia, Marta; Hauptman, Joe; Walshaw, Richard

    2003-01-01

    To determine whether atropine altered the degree of mucosal eversion during jejunal resection and anastomosis in the dog. Part I: Prospective, blinded, randomized, controlled study using a therapeutic dose (0.04 mg/kg systemic) of atropine. Part II: Prospective, unblinded, assigned, controlled study using a pharmacologic (0.04 mg/kg local arterial) dose of atropine. Part I: Twenty-two young adult female Beagle dogs used during a nonsurvival third-year veterinary student surgical laboratory (small intestinal resection and anastomosis). Part II: Ten young adult female Beagle dogs used immediately after completion of a nonsurvival third-year veterinary student orthopedic surgical laboratory. Part I: Dogs were randomly assigned to receive either atropine (0.04 mg/kg), or an equal volume of saline, given intramuscularly (premedication) and again intravenously prior to intestinal resection. Part II: In each dog, atropine (0.04 mg/kg)/saline was alternately given in the proximal/distal jejunum. Part I: There was no clinically or statistically significant difference between systemic atropine and saline solution on the degree of jejunal mucosal eversion after resection. Part II: There was a statistically significant decrease in jejunal mucosal eversion with atropine compared with saline solution when injected into a local jejunal artery. Systemic atropine (0.04 mg/kg) does not alter the degree of jejunal mucosal eversion during resection and anastomosis. Jejunal intraarterial atropine (0.04 mg/kg) reduced jejunal mucosal eversion during resection and anastomosis. The clinical usefulness and consequences of jejunal arterial atropine administration to reduce mucosal eversion remain to be determined. Copyright 2003 by The American College of Veterinary Surgeons

  1. Microvascular anastomosis using the vascular closure device in free flap reconstructive surgery: A 13-year experience.

    Science.gov (United States)

    Reddy, Chaitan; Pennington, David; Stern, Harvey

    2012-02-01

    The achievement of patency of the microvascular anastomosis in free flap surgery is dependent on a number of factors, central to which is atraumatic handling of the vessel lumen, and intimal apposition. Initial laboratory studies demonstrating the superiority of the non-penetrating vascular closure staple (VCS - Anastoclip ®) were followed by our report in 1999 on a series of free flaps. There is still a paucity of data in the literature on the use of non-penetrating devices for microvascular anastomosis, and our review gives evidence to support the routine use of the VCS in microsurgical free flap surgery. We now report on its successful use over a thirteen year period in 819 free flap reconstructions. Our data indicates the VCS device to be as effective as sutured anastomoses in free tissue transfer surgery. There is also statistically significant data (Barnard's Exact Test) to demonstrate a higher vascular patency rate of the VCS device over sutured anastomoses when sub group analysis is performed. 'Take-back' revision rates were lower amongst flaps that employed VCS use. For arterial anastomoses, this equated to 3/654(0.05%) vs 4/170(2.4%) with hand-sewn anastomoses (p = 0.02). Similarly, for venous anastomoses the 'take-back' revision rate was 7/661(1.1%) vs 8/165(4.8%) with hand-sewn anastomoses (p = 0.003). Furthermore, the major advantage of the VCS is reduction in anastomosis time, from approximately 25 min per anastomosis for sutures to between five and 10 min for staples. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  2. Introduction of a potent single-donor fibrin glue for vascular anastomosis: An animal study

    Directory of Open Access Journals (Sweden)

    Mehdi Rasti Ardakani

    2012-01-01

    Full Text Available Background: Vascular anastomosis is considered as a difficult surgical procedure. Although different alternative methods have been tried to tackle these difficulties, none were found to be successful. Commercial fibrin glue has recently been used for vascular anastomosis. However, it did not gain popularity due to some limitations such as low tensile strength, rapid removal by the immune system, and risk of transmission of blood-borne viral infections. In this article, we presented a novel method for producing single-donor human fibrin glue and determined its success rate for vascular anastomosis in an animal model. Materials ans Methods : In this study, 3 mL of single-donor fibrin sealant was prepared from 150 mL of whole blood containing 50-70 mg/mL of fibrinogen. The study was performed on 10 dogs and 5 cats. After transection of the carotid artery, both ends were anastomosed by means of 3-4 sutures (Prolene 8-0. The suture line was then sealed with one layer of the new fibrin sealant. After 3-8 weeks, the site of anastomosis was evaluated angiographically and morphologically for healing and possible complications such as thrombosis or aneurysm. Results: In evaluations 3 weeks after the surgery, all arterial anastomoses were patent in dogs, but some degree of subintimal hyperplasia was noted. After 8 weeks, all anastomoses were patent and the degree of subintimal hyperplasia was decreased. In cats on the other hand, after 4 weeks, all anastomoses were patent and subintimal hyperplasia was absent. Conclusions: Single-donor fibrin glue was a quite reliable and practical alternative to minimize suturing and therefore operative time in our animal model. This sealant can easily be obtained from the patient′s whole blood. Its application in humans would require further studies.

  3. What is the optimal management of an intra-operative air leak in a colorectal anastomosis?

    Science.gov (United States)

    Mitchem, J B; Stafford, C; Francone, T D; Roberts, P L; Schoetz, D J; Marcello, P W; Ricciardi, R

    2018-02-01

    An airtight anastomosis on intra-operative leak testing has been previously demonstrated to be associated with a lower risk of clinically significant postoperative anastomotic leak following left-sided colorectal anastomosis. However, to date, there is no consistently agreed upon method for management of an intra-operative anastomotic leak. Therefore, we powered a noninferiority study to determine whether suture repair alone was an appropriate strategy for the management of an intra-operative air leak. This is a retrospective cohort analysis of prospectively collected data from a tertiary care referral centre. We included all consecutive patients with left-sided colorectal or ileorectal anastomoses and evidence of air leak during intra-operative leak testing. Patients were excluded if proximal diversion was planned preoperatively, a pre-existing proximal diversion was present at the time of surgery or an anastomosis was ultimately unable to be completed. The primary outcome measure was clinically significant anastomotic leak, as defined by the Surgical Infection Study Group at 30 days. From a sample of 2360 patients, 119 had an intra-operative air leak during leak testing. Sixty-eight patients underwent suture repair alone and 51 underwent proximal diversion or anastomotic reconstruction. The clinically significant leak rate was 9% (6/68; 95% CI: 2-15%) in the suture repair alone arm and 0% (0/51) in the diversion or reconstruction arm. Suture repair alone does not meet the criteria for noninferiority for the management of intra-operative air leak during left-sided colorectal anastomosis. Further repair of intra-operative air leak by suture repair alone should be reconsidered given these findings. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

  4. Aberrant cervical vasculature anastomosis as cause of neck pain and successful treatment with embolization technique.

    Science.gov (United States)

    He, Lucy; Ladner, Travis R; Cobb, Mark; Mocco, J

    2016-01-27

    We report a patient with non-dermatomal radiating neck pain without focal neurologic deficit. Traditional workup could not identify an anatomic or biomechanical cause. Imaging showed a deep cervical vessel centered in the region of pain. Angiography later identified an aberrant anastomosis of this vessel with the occipital artery. Subsequent endovascular embolization of this arterial trunk resulted in complete pain relief. 2016 BMJ Publishing Group Ltd.

  5. Immediate primary anastomosis for isolated oesophageal atresia: A single-centre experience

    Directory of Open Access Journals (Sweden)

    Ibrahim Uygun

    2015-01-01

    Full Text Available Background: Isolated oesophageal atresia without tracheo-oesophageal fistula represents a major challenge for most paediatric surgeons. Here, we present our experience with six neonates with isolated oesophageal atresia who successfully underwent immediate primary anastomosis using multiple Livaditis circular myotomy. Materials and Methods: All six neonates were gross type A isolated oesophageal atresia (6%, from among 102 neonates with oesophageal atresia, treated between January 2009 and December 2013. Five neonates were female; one was male. The mean birth weight was 2300 (range 1700-3100 g. Results: All six neonates successfully underwent immediate primary anastomosis using multiple myotomies (mean 3; range 2-4 within 10 (median 3 days after birth. The gap under traction ranged from 6 to 7 cm. One neonate died of a major cardiac anomaly. Another neonate was lost to follow-up after being well for 3 months. Three anastomotic strictures were treated with balloon dilatation, and four anastomotic leaks were treated conservatively. The mean duration of follow-up was 33 months. Conclusions: To treat isolated oesophageal atresia, an immediate primary anastomosis can be achieved using multiple myotomies. Although, this approach is associated with high complication rates, as are other similar approaches, these complications can be overcome.

  6. Long-term assessments after pancreaticoduodenectomy with pancreatic duct invagination anastomosis

    International Nuclear Information System (INIS)

    Fujino, Yasuhiro; Matsumoto, Ippei; Sakai, Tetsuya; Ajiki, Tetsuo; Ueda, Takashi; Kuroda, Yoshikazu; Suzuki, Yasuyuki

    2007-01-01

    The purpose of this cohort was to evaluate the long-term patency of the anastomosis and the remnant pancreatic functions. Fifty-six consecutive patients undergoing a pancreaticoduodenectomy with pancreatic duct invagination anastomosis were enrolled in this study. During the follow-up, changes in the remnant pancreatic duct size, pancreatic exocrine and endocrine functions, and nutritional status were monitored. No seriously activated pancreatic fistula, no hemorrhagic complications, no reoperations, and no in-hospital deaths were observed after surgery. A dilatation of remnant pancreatic duct was detected a total of 37 times (51%) during annual computed tomography (CT) evaluations. Pancreatic dysfunctions were observed in a considerable number of patients (exocrine 4/12, 9/14, and 8/16, endocrine 9/35, 8/27, and 4/16 at 1, 2, and 3 postoperative years, respectively). Functional declines in the remnant pancreas, duct dilatation, and a decrease in the body mass index were observed from the first year. However, these data did not progressively deteriorate thereafter, at least during the first 3 postoperative years. This study demonstrated a significant correlation between the duct dilatation and endocrine dysfunction. Our pancreatic duct invagination anastomosis resulted in somewhat limited long-term outcomes, although it did prevent serious complications in the short-term. (author)

  7. Tracheal anastomosis using indocyanine green dye enhanced fibrinogen with a near-infrared diode laser

    Science.gov (United States)

    Auteri, Joseph S.; Jeevanandam, Valluvan; Oz, Mehmet C.; Libutti, Steven K.; Kirby, Thomas J.; Smith, Craig R.; Treat, Michael R.

    1990-06-01

    A major obstacle to lung transplantation and combined heart- lung transplantation is dehiscence of the tracheobronchial anastomosis. We explored the possibility of laser welded anastomoses in canine tracheas in vivo. Laser anastomoses were performed on three-quarter circumferential anterior tracheotomies. A continous wave diode laser (808 +1 nm) at a power density of 9.6 watts/cm was used. Human fibrinogen was mixed with indocyanine green dye (ICG, max absorbance 805 nm) and applied to the anastomosis site prior to laser exposure. Animals were sacrificed at 0, 21 and 28 days post-operatively. At sacrifice weld bursting pressures were measured by raising intratracheal pressure using forced ventilation via an endotracheal tube. Sutured and laser welded anastomoses had similar bursting pressures, and exhibited satisfactory histologic evidence of healing. However, compared to polypropylene sutured controls, the laser welded anastomoses exhibited less peritracheal inflammatory reaction and showed visibly smoother luminal surfaces at 21 and 28 days post- operatively. Tracheal anastomosis using ICG dye enhanced fibrinogen combined with the near-infrared diode laser is a promising extension of the technology of laser tissue fusion and deserves further study.

  8. Cost and efficacy comparison of in vitro fertilization and tubal anastomosis for women after tubal ligation.

    Science.gov (United States)

    Messinger, Lauren B; Alford, Connie E; Csokmay, John M; Henne, Melinda B; Mumford, Sunni L; Segars, James H; Armstrong, Alicia Y

    2015-07-01

    To compare cost and efficacy of tubal anastomosis to in vitro fertilization (IVF) in women who desired fertility after a tubal ligation. Cost-effectiveness analysis. Not applicable. Not applicable. Not applicable. Cost per ongoing pregnancy. Cost per ongoing pregnancy for women after tubal anastomosis ranged from $16,446 to $223,482 (2014 USD), whereas IVF ranged from $32,902 to $111,679 (2014 USD). Across maternal age groups cost effective than IVF for ongoing pregnancy. Sensitivity analyses validated these findings across a wide range of ongoing pregnancy probabilities as well as costs per procedure. Tubal anastomosis was the most cost-effective approach for most women less than 41 years of age, whereas IVF was the most cost-effective approach for women aged ≥41 years who desired fertility after tubal ligation. A model was created that can be modified based on cost and success rates in individual clinics for improved patient counseling. Copyright © 2015 American Society for Reproductive Medicine. All rights reserved.

  9. Coronary artery bypass grafting hemodynamics and anastomosis design: a biomedical engineering review.

    Science.gov (United States)

    Ghista, Dhanjoo N; Kabinejadian, Foad

    2013-12-13

    In this paper, coronary arterial bypass grafting hemodynamics and anastomosis designs are reviewed. The paper specifically addresses the biomechanical factors for enhancement of the patency of coronary artery bypass grafts (CABGs). Stenosis of distal anastomosis, caused by thrombosis and intimal hyperplasia (IH), is the major cause of failure of CABGs. Strong correlations have been established between the hemodynamics and vessel wall biomechanical factors and the initiation and development of IH and thrombus formation. Accordingly, several investigations have been conducted and numerous anastomotic geometries and devices have been designed to better regulate the blood flow fields and distribution of hemodynamic parameters and biomechanical factors at the distal anastomosis, in order to enhance the patency of CABGs. Enhancement of longevity and patency rate of CABGs can eliminate the need for re-operation and can significantly lower morbidity, and thereby reduces medical costs for patients suffering from coronary stenosis. This invited review focuses on various endeavors made thus far to design a patency-enhancing optimized anastomotic configuration for the distal junction of CABGs.

  10. The Usefulness of Intraoperative Colonic Irrigation and Primary Anastomosis in Patients Requiring a Left Colon Resection.

    Science.gov (United States)

    Hong, Youngki; Nam, Soomin; Kang, Jung Gu

    2017-06-01

    The aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate. This retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes. Twenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8-39 days). Intraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation.

  11. A new technique of laparoscopic intracorporeal anastomosis for transrectal bowel resection with transvaginal specimen extraction.

    Science.gov (United States)

    Faller, Emilie; Albornoz, Jaime; Messori, Pietro; Leroy, Joël; Wattiez, Arnaud

    2013-01-01

    To show a new technique of laparoscopic intracorporeal anastomosis for transrectal bowel resection with transvaginal specimen extraction, a technique particularly suited for treatment of bowel endometriosis. Step-by-step explanation of the technique using videos and pictures (educative video). Endometriosis may affect the bowel in 3% to 37% of all endometriosis cases. Bowel endometriosis affects young women, without any co-morbidities and in particular without any vascular disorders. In addition, affected patients often express a desire for childbearing. Radical excision is sometimes required because of the impossibility of conservative treatment such as shaving, mucosal skinning, or discoid resection. Bowel endometriosis should not be considered a cancer, and consequently maximal resection is not the objective. Rather, the goal would be to achieve functional benefit. As a result, resection must be as economic and cosmetic as possible. The laparoscopic approach has proved its superiority over the open technique, although mini-laparotomy is generally performed to prepare for the anastomosis. Total laparoscopic approach in patients with partial bowel stenosis, using the vagina for specimen extraction. This technique of intracorporeal anastomosis with transvaginal specimen extraction enables a smaller resection and avoidance of abdominal incision enlargement that may cause hernia, infection, or pain. When stenosis is partial, this technique seems particularly suited for treatment of bowel endometriosis requiring resection. If stenosis is complete, the anvil can be inserted above the lesion transvaginally. Copyright © 2013 AAGL. Published by Elsevier Inc. All rights reserved.

  12. Coloanal anastomosis in the management of benign and malignant rectal disease

    Energy Technology Data Exchange (ETDEWEB)

    Drake, D.B.; Pemberton, J.H.; Beart, R.W. Jr.; Dozois, R.R.; Wolff, B.G.

    1987-11-01

    The aim was to determine the efficacy, safety, and long-term clinical and functional results of coloanal anastomosis in patients with complicated benign and malignant rectal disease. Twenty-nine patients underwent coloanal or colopouch-anal anastomosis for either carcinoma of the rectum not technically amenable to conventional low anterior resection, severe radiation injury, large benign lower third tumors, or complications of previous operations. The mean age of the patients was 61 years and 82% were men. A diverting colostomy was constructed in 55% of the patients. The mean (+/- SEM) length of follow-up was 20 +/- 3 months. There was no operative mortality. Transient urinary retention, however, occurred in 40%, anastomotic stricture in 28%, and anastomotic leakage in 3.4%. Four patients (14%) could not have intestinal continuity restored and therefore were considered failures. The stool frequency for all remaining patients (N = 25) was 3 +/- 1 per day (mean +/- SEM) and did not vary with age, sex, or indication for operation. Complete continence was achieved by 84% of patients, but no patient was incapacitated by poor bowel function. In patients in whom a conventional colorectostomy is impractical or unwise, coloanal anastomosis is a safe and efficacious alternative operation that preserves anal continence.

  13. The effect of erythropoietin on healing of obstructive vs nonobstructive left colonic anastomosis: an experimental study

    Directory of Open Access Journals (Sweden)

    Renda Nurten

    2007-05-01

    Full Text Available Abstract Background Anastomotic leakage is an important problem following primary resection in the left colon and is even more prominent when obstruction is present. We aimed to evaluate the possible effects of erythropoietin on the healing of anastomosis under both obstructive and non-obstructive states. Methods Forty male Wistar albino rats were divided into four groups. In group I, two cm left colonic resection and primary anastomosis were done. In group II, left colon were completely ligated and 24 hours later animals were re-operated for segmental resection. The same procedures were performed for rats in group III and IV in respect to group I and II and, 500 IU/kg a day erythropoietin were given in the latter two groups for seven days. For the quantative description of anastomotic healing mechanical, biochemical and histopathological parameters were employed on the seventh day and the animals were sacrificied. Results Although erythropoietin had positive effects on bursting pressure in group IV when compared to group II, it has no effect in group III. Despite the increased tissue hydroxyproline levels in group IV, erythropoietin failed to show any effects in group III. Erythropoietin had positive effects on neovascularization, fibroblast proliferiation and storage of collagen in group IV. Conclusion We failed to find any direct and evident effects of erythropoietin on healing of left colonic anastomosis. On the other hand, erythropoietin might prevent negative effects of obstruction on healing.

  14. [Transanal laparoscopic radical resection with telescopic anastomosis for low rectal cancer].

    Science.gov (United States)

    Li, Shiyong; Chen, Gang; Du, Junfeng; Chen, Guang; Wei, Xiaojun; Cui, Wei; Yuan, Qiang; Sun, Liang; Bai, Xue; Zuo, Fuyi; Yu, Bo; Dong, Xing; Ji, Xiqing

    2015-06-01

    To assess the safety, feasibility and clinical outcome of laparoscopic radical resection for low rectal cancer with telescopic anastomosis or with colostomy by stapler through transanal resection without abdominal incisions. From January 2010 to September 2014, 37 patients underwent laparoscopic radical resection for low rectal cancer through transanal resection without abdominal incisions. The tumors were 4-7 cm above the anal verge. On preoperative assessment, 26 cases were T1N0M0 and 11 were T2N0M0. For all cases, successful surgery was performed. In telescopic anastomosis group, the mean operative time was (178±21) min, with average blood loss of (76±11) ml and (13±7) lymph nodes harvested. Return of bowel function was (3.0±1.2) d and the hospital stay was (12.0±4.2) d without postoperative complications. Patients were followed up for 3-45 months. Twelve months after surgery, 94.6%(35/37) patients achieved anal function Kirwan grade 1, indicating that their anal function returned to normal. Laparoscopic radical resection for low rectal cancer with telescopic anastomosis or colostomy by stapler through transanal resection without abdominal incisions is safe and feasible. Satisfactory clinical outcome can be achieved mini-invasively.

  15. Ileo-ceco-rectal Intussusception Requiring Intestinal Resection and Anastomosis in a Tawny Eagle (Aquila rapax).

    Science.gov (United States)

    Sabater, Mikel; Huynh, Minh; Forbes, Neil

    2015-03-01

    A 23-year-old male tawny eagle (Aquila rapax) was examined because of sudden onset of lethargy, regurgitation, and hematochezia. An intestinal obstruction was suspected based on radiographic findings, and an ileo-ceco-rectal intussusception was confirmed by coelioscopy. A 14.3-cm section of intestine was resected before an intestinal anastomosis was done. Coelomic endoscopic examination confirmed a postsurgical complication of adhesions between the intestinal anastomosis and the dorsal coelomic wall, resulting in a partial luminal stricture and requiring surgical removal of the adhesions. Rectoscopy was useful in diagnosing a mild luminal stricture related to the second surgery. Complete recovery was observed 2 months after surgery. Lack of further complications in the 2 years after surgery demonstrates good tolerance of intestinal resection and anastomosis of a large segment of bowel in an eagle. This report is the first reported case of intussusception in an eagle and emphasizes the potential use of endoscopic examination in the diagnosis as well as in the management of complications.

  16. Parks coloanal pull-through anastomosis for severe, complicated radiation proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Gazet, J.C.

    1985-02-01

    A variety of operations have been proposed for the treatment of radiation injuries of the rectum. In this study, the procedure advocated by the late Sir Alan Parks--resection of the diseased segment down to its points of fixation to the vagina, bladder or prostate; with perianal mucosal stripping of the anorectal segment and primary coloanal (pull-through) anastomosis--was performed in 11 patients. In two others, an attempt at colorectal anastomosis was abandoned because of extreme scarring in the pelvis. The procedures were done following definitive treatment of carcinoma of the rectum (seven patients), carcinoma of the cervix (two patients), carcinoma of the uterus (one patient), carcinoma of the ovary (one patient), seminoma (one patient), and carcinoma of the bladder (one patient). One patient died from a pulmonary embolus on the seventh postoperative day. Of the survivors with a coloanal anastomosis, all had successful closure of their temporary colostomies with follow-up from one to six years. In eight, continence was assessed as being good or excellent. Four patients required anastomotic dilation and another required a surgical procedure for anastomotic stricture. There was one instance each of reoperation for small bowel obstruction and ileocolic fistula. There were no instances of recurrence of hemorrhage, fistulas, perineal pain or tenesmus. The Parks procedure obviates the need for a difficult dissection of the lower rectum and separation of tissues damaged by radiation and avoids the need for eversion techniques. Its selective use is advocated for patients suffering from severe radiation injuries of the rectum.

  17. [Segmental tracheal resection and anastomosis for the treatment of cicatricial stenosis in cervical tracheal].

    Science.gov (United States)

    Cui, P C; Luo, J S; Liu, Z; Bian, K; Guo, Z H; Ma, R N

    2016-02-01

    To evaluate the efficacy of segmental tracheal resection with end-to-end anastomosis for cicatricial cervical tracheal stenosis. The clinical outcomes of 40 patients treated with tracheal resection were retrospectively reviewed. There were 28 male patients and 12 female patients with the age ranged from 6 to 64 years (mean 33.7 years). The degree of stenosis was classified according to Myer-Cotton classification as follows: grade Ⅱ (n=7), grade Ⅲ (n=22) and grade Ⅳ (n=11). The stenosis extension ranged from 1.0 to 4.3 cm (mean 2.5 cm). The causes of the stenosis were postintubation (n=33), cervical trauma (n=6) and resection of tracheal neoplasm (n=1). Thirty-four(85.0%) patients were decannulated and 6 failed. Of the 6 patients failed, 4 were decannulated after reoperation with the sternohyoid myocutaneous flap or thyroid alar cartilage graft. Complications occurred in 10 patients. In 8 patients granulation tissues formed at the site of the tracheal anastomosis, which needed endoscopic resction, and in 2 patients anastomosic dehiscence occurred. No injury to recurrent laryngeal nerve or trachoesophageal fistula occurred. Segmental tracheal resection with end-to-end anastomosis is an effective surgical method for tracheal stenosis, which has a higher successful rate for primary operation and shorter therapeutic period.

  18. Segmental resection with primary anastomosis is not always safe in splenic flexure perforation.

    Science.gov (United States)

    Weledji, Elroy P; Mokake, Martin D; Sinju, Motaze

    2016-01-16

    Familial adenomatous polyposis (FAP) is caused by a rare mutation of the adenomatous polyposis coli gene on Chromosome 5q. The risk of colorectal cancer in patients with FAP is nearly 100% and intensive endoscopic surveillance or prophylactic colectomy are mandatory. If extensive endoscopic surveillance is chosen, there is a cumulative risk of perforation and bleeding especially after polypectomy. We discussed the problems and options in the management of the late diagnosis of an iatrogenic perforation of the splenic flexure complicating endoscopic surveillance in FAP. We present a 35-year-old black African man with FAP who sustained a splenic flexure perforation following a colonoscopic polypectomy of a suspicious lesion. He underwent a splenic flexure resection and primary anastomosis that dehisced and the patient benefited from an emergency definitive colectomy and ileorectal anastomosis. Resection with primary anastomosis following iatrogenic perforation of the splenic flexure is not safe because of a high chance of anastomotic dehiscence. Following a late diagnosis in an unstable patient exteriorization of the perforation as a stoma is a better option prior to a definitive prophylactic colectomy.

  19. Coloanal anastomosis in the management of benign and malignant rectal disease

    International Nuclear Information System (INIS)

    Drake, D.B.; Pemberton, J.H.; Beart, R.W. Jr.; Dozois, R.R.; Wolff, B.G.

    1987-01-01

    The aim was to determine the efficacy, safety, and long-term clinical and functional results of coloanal anastomosis in patients with complicated benign and malignant rectal disease. Twenty-nine patients underwent coloanal or colopouch-anal anastomosis for either carcinoma of the rectum not technically amenable to conventional low anterior resection, severe radiation injury, large benign lower third tumors, or complications of previous operations. The mean age of the patients was 61 years and 82% were men. A diverting colostomy was constructed in 55% of the patients. The mean (+/- SEM) length of follow-up was 20 +/- 3 months. There was no operative mortality. Transient urinary retention, however, occurred in 40%, anastomotic stricture in 28%, and anastomotic leakage in 3.4%. Four patients (14%) could not have intestinal continuity restored and therefore were considered failures. The stool frequency for all remaining patients (N = 25) was 3 +/- 1 per day (mean +/- SEM) and did not vary with age, sex, or indication for operation. Complete continence was achieved by 84% of patients, but no patient was incapacitated by poor bowel function. In patients in whom a conventional colorectostomy is impractical or unwise, coloanal anastomosis is a safe and efficacious alternative operation that preserves anal continence

  20. [Replantation of fingertip amputation in lack of availability of intravenous anastomosis].

    Science.gov (United States)

    Wei, Jian-Min; Sun, Jun-Suo; Jiao, Xiao-Hu; Jing, Dou-Xing; He, Wei; Jin, Wen-Kuo; Chen, Shi-Gao

    2012-08-01

    To discuss the replantation of fingertip amputation in lack of availability of intravenous anastomosis. From November 2009 to November 2010, 86 patients (104 fingers) with fingertip amputation were treated with replantatioin, including 64 males and 22 females, with an average age of 26 years ranging from 2 to 64 years. The time from injury to therapy was from 30 min to 12 h, time of broken finger ischemia was from 2.5 to 12 h. Preoperative examination showed no obvious abnormalities. Four different replantation methods were selectively applied to these 104 amputated fingertips of 86 cases: (1) replantation with anastomosis of single or bilateral proper digital artery in 37 fingers; (2) replantation with arteriovenous bypass in 27 fingers; (3) replantation with exclusive anastomosis of digital artery in 24 fingers; (4) replantation with removing the palmar pocket method in 16 fingers. One hundred and two of 104 amputated fingertips were survived. Among these survived fingers,75 cases (92 fingers) were followed-up for 6 to 24 months. According to the assessment standard of Chinese Medical Association of Hand Surgery, the results were excellent in 52 cases, good in 19, poor in 4. It benefits to expand the indications and improve the survival rate of replantation of fingertip amputation with the correct choice of different replantation methods according to the injury situation of the broken fingertip artery after debridement under the microscope.

  1. Parks coloanal pull-through anastomosis for severe, complicated radiation proctitis

    International Nuclear Information System (INIS)

    Gazet, J.C.

    1985-01-01

    A variety of operations have been proposed for the treatment of radiation injuries of the rectum. In this study, the procedure advocated by the late Sir Alan Parks--resection of the diseased segment down to its points of fixation to the vagina, bladder or prostate; with perianal mucosal stripping of the anorectal segment and primary coloanal (pull-through) anastomosis--was performed in 11 patients. In two others, an attempt at colorectal anastomosis was abandoned because of extreme scarring in the pelvis. The procedures were done following definitive treatment of carcinoma of the rectum (seven patients), carcinoma of the cervix (two patients), carcinoma of the uterus (one patient), carcinoma of the ovary (one patient), seminoma (one patient), and carcinoma of the bladder (one patient). One patient died from a pulmonary embolus on the seventh postoperative day. Of the survivors with a coloanal anastomosis, all had successful closure of their temporary colostomies with follow-up from one to six years. In eight, continence was assessed as being good or excellent. Four patients required anastomotic dilation and another required a surgical procedure for anastomotic stricture. There was one instance each of reoperation for small bowel obstruction and ileocolic fistula. There were no instances of recurrence of hemorrhage, fistulas, perineal pain or tenesmus. The Parks procedure obviates the need for a difficult dissection of the lower rectum and separation of tissues damaged by radiation and avoids the need for eversion techniques. Its selective use is advocated for patients suffering from severe radiation injuries of the rectum

  2. In vivo perfusion assessment of an anastomosis surgery on porcine intestinal model (Conference Presentation)

    Science.gov (United States)

    Le, Hanh N. D.; Opferman, Justin; Decker, Ryan; Cheon, Gyeong W.; Kim, Peter C. W.; Kang, Jin U.; Krieger, Axel

    2016-04-01

    Anastomosis, the connection of two structures, is a critical procedure for reconstructive surgery with over 1 million cases/year for visceral indication alone. However, complication rates such as strictures and leakage affect up to 19% of cases for colorectal anastomoses and up to 30% for visceral transplantation anastomoses. Local ischemia plays a critical role in anastomotic complications, making blood perfusion an important indicator for tissue health and predictor for healing following anastomosis. In this work, we apply a real time multispectral imaging technique to monitor impact on tissue perfusion due to varying interrupted suture spacing and suture tensions. Multispectral tissue images at 470, 540, 560, 580, 670 and 760 nm are analyzed in conjunction with an empirical model based on diffuse reflectance process to quantify the hemoglobin oxygen saturation within the suture site. The investigated tissues for anastomoses include porcine small (jejunum and ileum) and large (transverse colon) intestines. Two experiments using interrupted suturing with suture spacing of 1, 2, and 3 mm and tension levels from 0 N to 2.5 N are conducted. Tissue perfusion at 5, 10, 20 and 30 min after suturing are recorded and compared with the initial normal state. The result indicates the contrast between healthy and ischemic tissue areas and assists the determination of suturing spacing and tension. Therefore, the assessment of tissue perfusion will permit the development and intra-surgical monitoring of an optimal suture protocol during anastomosis with less complications and improved functional outcome.

  3. Dynamic Liver Magnetic Resonance Imaging in Free-Breathing: Feasibility of a Cartesian T1-Weighted Acquisition Technique With Compressed Sensing and Additional Self-Navigation Signal for Hard-Gated and Motion-Resolved Reconstruction.

    Science.gov (United States)

    Kaltenbach, Benjamin; Bucher, Andreas M; Wichmann, Julian L; Nickel, Dominik; Polkowski, Christoph; Hammerstingl, Renate; Vogl, Thomas J; Bodelle, Boris

    2017-11-01

    The aim of this study was to assess the feasibility of a free-breathing dynamic liver imaging technique using a prototype Cartesian T1-weighted volumetric interpolated breathhold examination (VIBE) sequence with compressed sensing and simultaneous acquisition of a navigation signal for hard-gated and motion state-resolved reconstruction. A total of 43 consecutive oncologic patients (mean age, 66 ± 11 years; 44% female) underwent free-breathing dynamic liver imaging for the evaluation of liver metastases from colorectal cancer using a prototype Cartesian VIBE sequence (field of view, 380 × 345 mm; image matrix, 320 × 218; echo time/repetition time, 1.8/3.76 milliseconds; flip angle, 10 degrees; slice thickness, 3.0 mm; acquisition time, 188 seconds) with continuous data sampling and additionally acquired self-navigation signal. Data were iteratively reconstructed using 2 different approaches: first, a hard-gated reconstruction only using data associated to the dominating motion state (CS VIBE, Compressed Sensing VIBE), and second, a motion-resolved reconstruction with 6 different motion states as additional image dimension (XD VIBE, eXtended dimension VIBE). Continuous acquired data were grouped in 16 subsequent time increments with 11.57 seconds each to resolve arterial and venous contrast phases. For image quality assessment, both CS VIBE and XD VIBE were compared with the patient's last staging dynamic liver magnetic resonance imaging including a breathhold (BH) VIBE as reference standard 4.5 ± 1.2 months before. Representative quality parameters including respiratory artifacts were evaluated for arterial and venous phase images independently, retrospectively and blindly by 3 experienced radiologists, with higher scores indicating better examination quality. To assess diagnostic accuracy, same readers evaluated the presence of metastatic lesions for XD VIBE and CS VIBE compared with reference BH examination in a second session. Compared with CS VIBE, XD VIBE

  4. Paradoxical Impact of Ileal Pouch-Anal Anastomosis on Male and Female Fertility in Patients With Ulcerative Colitis.

    Science.gov (United States)

    Pachler, Frederik R; Brandsborg, Søren B; Laurberg, Søren

    2017-06-01

    Birth rates in males with ulcerative colitis and ileal pouch-anal anastomosis have not been studied. This study aimed to estimate birth rates in males and females with ulcerative colitis and study the impact of ileal pouch-anal anastomosis. This was a retrospective registry-based cohort study that was performed over a 30-year period. Records for parenting a child from the same period were cross-linked with patient records, and birth rates were calculated using 15 through 49 years as age limits. All data were prospectively registered. All patients with ulcerative colitis and ulcerative colitis with ileal pouch-anal anastomosis between 1980 and 2010 were identified in Danish national databases. The primary outcomes measured were birth rates in females and males with ulcerative colitis and ulcerative colitis with ileal pouch-anal anastomosis. We included 27,379 patients with ulcerative colitis (12,812 males and 14,567 females); 1544 had ileal pouch-anal anastomosis (792 males and 752 females). Patients with ulcerative colitis have slightly reduced birth rates (males at 40.8 children/1000 years, background population 43.2, females at 46.2 children/1000 years, background population 49.1). After ileal pouch-anal anastomosis, males had increased birth rates at 47.8 children/1000 years in comparison with males with ulcerative colitis without ileal pouch-anal anastomosis (40.5 children/1000 years), whereas females had reduced birth rates at 27.6 children/1000 years in comparison with females with ulcerative colitis without ileal pouch-anal anastomosis (46.8 children/1000 years). Only birth rates were investigated and not fecundability. Furthermore, there is a question about misattributed paternity, but this has previously been shown to be less than 5%. Ulcerative colitis per se has little impact on birth rates in both sexes, but ileal pouch-anal anastomosis surgery leads to a reduction in birth rates in females and an increase in birth rates in males. This has clinical

  5. MEMS-based handheld fourier domain Doppler optical coherence tomography for intraoperative microvascular anastomosis imaging.

    Directory of Open Access Journals (Sweden)

    Yong Huang

    Full Text Available To demonstrate the feasibility of a miniature handheld optical coherence tomography (OCT imager for real time intraoperative vascular patency evaluation in the setting of super-microsurgical vessel anastomosis.A novel handheld imager Fourier domain Doppler optical coherence tomography based on a 1.3-µm central wavelength swept source for extravascular imaging was developed. The imager was minimized through the adoption of a 2.4-mm diameter microelectromechanical systems (MEMS scanning mirror, additionally a 12.7-mm diameter lens system was designed and combined with the MEMS mirror to achieve a small form factor that optimize functionality as a handheld extravascular OCT imager. To evaluate in-vivo applicability, super-microsurgical vessel anastomosis was performed in a mouse femoral vessel cut and repair model employing conventional interrupted suture technique as well as a novel non-suture cuff technique. Vascular anastomosis patency after clinically successful repair was evaluated using the novel handheld OCT imager.With an adjustable lateral image field of view up to 1.5 mm by 1.5 mm, high-resolution simultaneous structural and flow imaging of the blood vessels were successfully acquired for BALB/C mouse after orthotopic hind limb transplantation using a non-suture cuff technique and BALB/C mouse after femoral artery anastomosis using a suture technique. We experimentally quantify the axial and lateral resolution of the OCT to be 12.6 µm in air and 17.5 µm respectively. The OCT has a sensitivity of 84 dB and sensitivity roll-off of 5.7 dB/mm over an imaging range of 5 mm. Imaging with a frame rate of 36 Hz for an image size of 1000(lateral×512(axial pixels using a 50,000 A-lines per second swept source was achieved. Quantitative vessel lumen patency, lumen narrowing and thrombosis analysis were performed based on acquired structure and Doppler images.A miniature handheld OCT imager that can be used for intraoperative evaluation of

  6. Compressive laser ranging.

    Science.gov (United States)

    Babbitt, Wm Randall; Barber, Zeb W; Renner, Christoffer

    2011-12-15

    Compressive sampling has been previously proposed as a technique for sampling radar returns and determining sparse range profiles with a reduced number of measurements compared to conventional techniques. By employing modulation on both transmission and reception, compressive sensing in ranging is extended to the direct measurement of range profiles without intermediate measurement of the return waveform. This compressive ranging approach enables the use of pseudorandom binary transmit waveforms and return modulation, along with low-bandwidth optical detectors to yield high-resolution ranging information. A proof-of-concept experiment is presented. With currently available compact, off-the-shelf electronics and photonics, such as high data rate binary pattern generators and high-bandwidth digital optical modulators, compressive laser ranging can readily achieve subcentimeter resolution in a compact, lightweight package.

  7. Anastomosis Martin-Gruber: Aspectos anatómicos y electrofisiológicos Martin-Gruber Anastomosis: Anatomical and electrophysiological issues

    Directory of Open Access Journals (Sweden)

    Esperanza Herrera

    2009-08-01

    Full Text Available La anastomosis de Martin Gruber (AMG es una de las variaciones anatómicas más frecuentes que consiste en la contribución de axones motores desde el nervio mediano hacia el ulnar en el antebrazo. Factores filogenéticos y genéticos se asocian con la aparición de la AMG. Entre tanto, otros factores como género, raza o lateralidad no parecen tener importancia en la aparición de la rama comunicante. Las clasificaciones de la AMG han sido establecidas según los hallazgos anatómicos, electrofisiológicos e histológicos y también según el lugar de origen y destino de la anastomosis. El objetivo de este artículo es revisar los factores asociados a la presencia de la AMG, así como las descripciones y clasificaciones anatómicas y electrofisiológicas. Esta revisión aporta información relevante para el reconocimiento de los patrones clásico y variante de inervación de la musculatura intrínseca de la mano. Dicho reconocimiento permite diagnosticar e intervenir apropiadamente las alteraciones de los nervios periféricos de la extremidad superior. Salud UIS 2009; 41: 157-168The Martin Gruber Anastomosis (MGA is one of the most common anatomical variants of the upper limb, which consists of motor axons crossing through the forearm from the median nerve to the ulnar nerve. Phylogenetic and hereditary factors have been associated whit the MGA. However, gender, race, or laterality, do not seem to have importance in the appearance of the communicating branch. The MGA has been categorized according to findings in anatomy, electrophysiology and histology, in relation to the source and destination of the communicating branch. The aim of this article is to review the factors related to the presence of MGA, as well as the descriptions and classifications according to anatomy and electrophysiology. This revision contributes with important information relevant to the recognition of differences between the classic pattern and the variant pattern of the

  8. 磁共振断层血管成像在颅神经血管压迫综合征的应用%Magnetic resonance tomographic angiography in cranial neurovascular compression syndrome

    Institute of Scientific and Technical Information of China (English)

    胡兴荣; 李顺振; 邓民强; 陈华东; 邱妮妮

    2010-01-01

    Objective To investigate the clinical diagnostic value of magnetic resonance tomographic angiography (MRTA) on cranial neurovascular compression syndrome,and evaluate the ability of 3D-FIESTA and 3D-TOF-SPGR sequences in demonstrating the relation of three-dimensional space between cranial nerves and blood vessels.Methods The data of 41 patients with cranial neurovascular compression syndrome,admitted to our hospital from May 2007 to May 2009,were analyzed.These patients were planed to perform micro vasular decompression (MVD).Before the operation,MRTA,3D-FIESTA and 3D-TOF-SPGR sequence scanning were performed to observe the relation of three-dimensional space between cranial nerves and blood vessels;these results were compared with the intraoperative results to evaluate the advantages and disadvantages of 3D-FIESTA and 3D-TOF-SPGR sequence scanning.Results MRTA could demonstrate such cranial nerves as trigeminal nerve,facial nerve and glossopharyngeal nerve,and responsible blood vessels clearly and simultaneously.The 3D-FIESTA imaging showed high signal in the cerebrospinal fluid and moderate signal in the nerves and blood vessels.The 3D-TOF-SPGR imaging showed low signal in the cerebrospinai fluid,moderate signal in the nerves and brain parenchyma,and high signal in the blood vessels.Closed relation between the nerves and the blood vessels in the lesion side were found in 34 patients (82.9%) by 3D-FIESTA sequence scanning,and that was found in 35 patients by 3D-TOF-SPGR sequence scanning; no significant difference between 3D-FIESTA and 3D-TOF-SPGR sequence scanning was found in displaying the relation of nerves and blood vessels (P>0.05).Conclusion MRTA technology may clearly show the relation of cranial nerves and responsible blood vessels;combined application of 3D-FIESTA and 3D-TOF-SPGR sequence scanning can help making the preoperative diagnosis and determining the surgical indications in patients with cranial neurovaseular compression syndrome.%目的 探

  9. Healing of esophageal anastomoses performed with the biofragmentable anastomosis ring versus the end-to-end anastomosis stapler: comparative experimental study in dogs.

    Science.gov (United States)

    Kovács, Tibor; Köves, István; Orosz, Zsolt; Németh, Tibor; Pandi, Erzsébet; Kralovanszky, Judit

    2003-04-01

    The biofragmentable anastomosis ring (BAR) has been used successfully for anastomoses from the stomach to the upper rectum. The healing of intrathoracic esophageal anastomoses performed with the BAR or an end-to-end anastomosis (EEA) stapler on an experimental model was compared. Parameters of tissue repair were evaluated: macroscopic examination, bursting strength (BS), collagen (hydroxyproline, or HP), histology (H&E and Picrosirius red staining for collagen). A series of 48 mongrel dogs were randomly separated into two groups (30 BAR, 18 stapler) and subgroups according to the time of autopsy (days 4, 7, 14, 28). Mortality was 13.3% (4 BAR cases) with two deaths not related to surgery (excluded). There were four leaks in the BAR group (14.3%) and no leaks or deaths but two strictures in the stapler group. BS was significantly higher in the BAR group during the first week, and values were almost equal from the second week with both methods. The HP rate was significantly reduced on days 4 and 7 in both groups compared to the reference values; the values were close to reference values from the second week (lower in the BAR group). Stapled anastomoses caused less pronounced inflammation and were associated with an earlier start of regeneration, but the difference was not significant compared to that in the BAR group. Accumulation of new collagen (green polarization) started on day 7 in both groups, but maturation (orange-red polarization) was significantly more advanced in the BAR group after the second week. A strong linear correlation between the BS and HP rate was found with both methods. There was no significant difference in the complication rate or healing of intrathoracic BAR and stapled anastomoses. The BAR method is simple, quick, and safe; and it seems to be a feasible procedure for creating intrathoracic esophageal anastomoses in dogs.

  10. Electromagnetic ion cyclotron waves stimulated by modest magnetospheric compressions

    Science.gov (United States)

    Anderson, B. J.; Hamilton, D. C.

    1993-01-01

    AMPTE/CCE magnetic field and particle data are used to test the suggestion that increased hot proton temperature anisotropy resulting from convection during magnetospheric compression is responsible for the enhancement in Pc 1 emission via generation of electromagnetic ion cyclotron (EMIC) waves in the dayside outer equatorial magnetosphere. The relative increase in magnetic field is used to gauge the strength of the compression, and an image dipole model is used to estimate the motion of the plasma during compression. Proton data are used to analyze the evolution of the proton distribution and the corresponding changes in EMIC wave activity expected during the compression. It is suggested that enhancements in dynamic pressure pump the energetic proton distributions in the outer magnetosphere, driving EMIC waves. Waves are expected to be generated most readily close to the magnetopause, and transient pressure pulses may be associated with bursts of EMIC waves, which would be observed on the ground in association with ionospheric transient signatures.

  11. Alcohol acute intoxication before sepsis impairs the wound healing of intestinal anastomosis: rat model of the abdominal trauma patient

    Directory of Open Access Journals (Sweden)

    Morais Pedro

    2012-08-01

    Full Text Available Abstract Introduction Most trauma patients are drunk at the time of injury. Up to 2% of traumatized patients develop sepsis, which considerably increases their mortality. Inadequate wound healing of the colonic repair can lead to postoperative complications such as leakage and sepsis. Objective To assess the effects of acute alcohol intoxication on colonic anastomosis wound healing in septic rats. Methods Thirty six Wistar rats were allocated into two groups: S (induction of sepsis and AS (alcohol intake before sepsis induction. A colonic anastomosis was performed in all groups. After 1, 3 or 7 days the animals were killed. Weight variations, mortality rate, histopathology and tensile breaking strength of the colonic anastomosis were evaluated. Results There was an overall mortality of 4 animals (11.1%, three in the group AS (16.6% and one in the S group (5.5%. Weight loss occurred in all groups. The colon anastomosis of the AS group didn’t gain strength from the first to the seventh postoperative day. On the histopathological analysis there were no differences in the deposition of collagen or fibroblasts between the groups AS and S. Conclusion Alcohol intake increased the mortality rate three times in septic animals. Acute alcohol intoxication delays the acquisition of tensile strength of colonic anastomosis in septic rats. Therefore, acute alcohol intoxication before sepsis leads to worse prognosis in animal models of the abdominal trauma patients.

  12. Optical pulse compression

    International Nuclear Information System (INIS)

    Glass, A.J.

    1975-01-01

    The interest in using large lasers to achieve a very short and intense pulse for generating fusion plasma has provided a strong impetus to reexamine the possibilities of optical pulse compression at high energy. Pulse compression allows one to generate pulses of long duration (minimizing damage problems) and subsequently compress optical pulses to achieve the short pulse duration required for specific applications. The ideal device for carrying out this program has not been developed. Of the two approaches considered, the Gires--Tournois approach is limited by the fact that the bandwidth and compression are intimately related, so that the group delay dispersion times the square of the bandwidth is about unity for all simple Gires--Tournois interferometers. The Treacy grating pair does not suffer from this limitation, but is inefficient because diffraction generally occurs in several orders and is limited by the problem of optical damage to the grating surfaces themselves. Nonlinear and parametric processes were explored. Some pulse compression was achieved by these techniques; however, they are generally difficult to control and are not very efficient. (U.S.)

  13. Compression anastomotic ring-locking procedure (CARP) is a safe and effective method for intestinal anastomoses following left-sided colonic resection

    DEFF Research Database (Denmark)

    Vilhjalmsson, Dadi; Appelros, Stefan; Toth, Ervin

    2015-01-01

    -sided colonic resection. Time for evacuation of the anastomotic rings, perioperative compression pressure, and adverse effects were recorded. Postoperative blood samples were collected daily, and flexible sigmoidoscopy was performed 8-12 weeks after surgery to examine the anastomoses. RESULTS: Fourteen out......BACKGROUND: Compression anastomotic ring-locking procedure (CARP) is a novel procedure for creating colonic anastomoses. The surgical procedure allows perioperative quantification of the compression pressure between the intestinal ends within the anastomosis and postoperative monitoring...... device evacuated spontaneously in all patients by the natural route after a median of 10 days. Perioperative compression pressure ranged between 85 and 280 mBar (median 130 mBar). Flexible sigmoidoscopy revealed smooth anastomoses without signs of pathological inflammation or stenosis in all cases...

  14. Drift Compression and Final Focus Options for Heavy Ion Fusion

    International Nuclear Information System (INIS)

    Hong Qin; Davidson, Ronald C.; Barnard, John J.; Lee, Edward P.

    2005-01-01

    A drift compression and final focus lattice for heavy ion beams should focus the entire beam pulse onto the same focal spot on the target. We show that this requirement implies that the drift compression design needs to satisfy a self-similar symmetry condition. For un-neutralized beams, the Lie symmetry group analysis is applied to the warm-fluid model to systematically derive the self-similar drift compression solutions. For neutralized beams, the 1-D Vlasov equation is solved explicitly, and families of self-similar drift compression solutions are constructed. To compensate for the deviation from the self-similar symmetry condition due to the transverse emittance, four time-dependent magnets are introduced in the upstream of the drift compression such that the entire beam pulse can be focused onto the same focal spot

  15. Effects on MR images compression in tissue classification quality

    International Nuclear Information System (INIS)

    Santalla, H; Meschino, G; Ballarin, V

    2007-01-01

    It is known that image compression is required to optimize the storage in memory. Moreover, transmission speed can be significantly improved. Lossless compression is used without controversy in medicine, though benefits are limited. If we compress images lossy, where image can not be totally recovered; we can only recover an approximation. In this point definition of 'quality' is essential. What we understand for 'quality'? How can we evaluate a compressed image? Quality in images is an attribute whit several definitions and interpretations, which actually depend on the posterior use we want to give them. This work proposes a quantitative analysis of quality for lossy compressed Magnetic Resonance (MR) images, and their influence in automatic tissue classification, accomplished with these images

  16. A clinical application of laser direction in anastomosis for inferior canalicular laceration

    Institute of Scientific and Technical Information of China (English)

    LIANG Tao; ZHAO Ke-xiao; ZHANG Ling-yun

    2006-01-01

    Objective:To study the therapeutic efficiency and effecacy of laser-directing approach on searching for the nasal broken end of lacerated lacrimal canaliculus in anastomosis for canalicular laceration.Methods: Forty-nine patients ( 49 eyes ) suffering from traumatic inferior canalicular laceration were divided into control group and laser-directing group. The distance between the lacrimal punctum and the nasal broken end of lacerated lacrimal canaliculus was more than 6 mm. During the course of management of eyelid trauma, the patients were treated by canalicular anastomosis operation with traditional method and laser-directing method in searching for the nasal broken end of lacerated lacrimal canaliculus respectively. The silicone tube of 1 mm diameter was intubated in the lacrimal passage as a stent for 4 to 6months.Results: In the laser-directing group, the mean time in searching for the nasal broken end of lacerated lacrimal canaliculus was (5.75 ± 1.49) minutes and the mean time of operation was (49.21±3.37) minutes; both were significantly shorter than that of the control group(P <0.01). The cure rate of the laser-directing group was96.55 %, higher than that of the control group but without statistical significance (P > 0.05).Conclusions: The laser-directing method is much quicker and more convenient to searching for the nasal broken end of the lacerated lacrimal canaliculus than the traditional approach, and patients suffer less pain and damaging in canalicular anastomosis operation.

  17. Uterovaginal Anastomosis for Cases of Cryptomenorrhea Due to Cervical Atresia with Vaginal Aplasia: Benefits and Risks.

    Science.gov (United States)

    Zayed, M; Fouad, R; Elsetohy, K A; Hashem, A T; AbdAllah, A A; Fathi, A I

    2017-12-01

    The objective of this study was to assess short-term benefits and risks of utero-vaginal anastomosis done for cases of cryptomenorrhea due to cervical atresia with vaginal aplasia. Prospective study. Surgical procedures were done between December 2013 and September 2015 at the department of Obstetrics and Gynecology, Cairo University Hospital. Five patients who had cryptomenorrhea due to cervical atresia associated with vaginal aplasia were included. Utero-vaginal anastomoses were performed in 2 stages; a stage of McIndoe vaginoplasty and a stage of excision of the atretic cervical tissue and anastomosing the uterus to the neovagina. Follow-up was done by gynecological and ultrasound examination in a duration ranged from 12 to 36 months. Occurrence of regular menstrual flow and relief of the severe cyclic pain. All patients had relief of the severe cyclic pain. Four patients had regular menstrual flow. One patient developed occlusion of the track after 1 year and needed dilatation once. Three patients developed low vaginal stenosis without occlusion of the track. One patient had rectal injury repaired without causing postoperative morbidity. Uterovaginal anastomosis is a promising conservative management option for cervical atresia with vaginal aplasia, which has benefits but is not free of risks. Long-term follow-up is still needed to judge its feasibility. We recommend performing McIndoe vaginoplasty as a starting stage before the anastomosis preferably in a separate setting. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  18. Safety of performing a delayed anastomosis during damage control laparotomy in patients with destructive colon injuries.

    Science.gov (United States)

    Ordoñez, Carlos A; Pino, Luis F; Badiel, Marisol; Sánchez, Alvaro I; Loaiza, Jhon; Ballestas, Leonardo; Puyana, Juan Carlos

    2011-12-01

    Recent studies report the safety and feasibility of performing delayed anastomosis (DA) in patients undergoing damage control laparotomy (DCL) for destructive colon injuries (DCIs). Despite accumulating experience in both civilian and military trauma, questions regarding how to best identify high-risk patients and minimize the number of anastomosis-associated complications remain. Our current practice is to perform a definitive closure of the colon during DCL, unless there is persistent acidosis, bowel wall edema, or evidence of intra-abdominal abscess. In this study, we evaluated the safety of this approach by comparing outcomes of patients with DCI who underwent definitive closure of the colon during DCL versus patients managed with colostomy with or without DCL. We performed a retrospective chart review of patients with penetrating DCI during 2003 to 2009. Severity of injury, surgical management, and clinical outcome were assessed. Sixty patients with severe gunshot wounds and three patients with stab wounds were included in the analysis. DCL was required in 30 patients, all with gunshot wounds. Three patients died within the first 48 hours, three underwent colostomy, and 24 were managed with DA. Thirty-three patients were managed with standard laparotomy: 26 patients with primary anastomosis and 7 with colostomy. Overall mortality rate was 9.5%. Three late deaths occurred in the DCL group, and only one death was associated with an anastomotic leak. Performing a DA in DCI during DCL is a reliable and feasible approach as long as severe acidosis, bowel wall edema, and/or persistent intra-abdominal infections are not present.

  19. [Cervical tracheal resection with primary anastomosis for benign tracheal stricture in adult].

    Science.gov (United States)

    Ye, Jin; Hu, Yan-Ming; Liu, Hui; Li, Jing-Jia; Wang, Zhi-Yuan; Li, Yuan

    2013-07-01

    To introduce the outcomes of tracheal resection with primary end to end anastomosis for benign cervical tracheal stenosis, and to discuss the strategy for prevention of surgical complications. A retrospective analysis was performed in 12 patients diagnosed as benign cervical tracheal stenosis from October 2009 to June 2012. Laryngo-tracheal endoscopic examination and computed tomography (CT) were used to assess the degree of stenosis, the grade of inflammation and edema of the subglottis and trachea, and the extent of stenosis and the remaining linear amount of normal airway. The Meyer and Cotton grading system was used to categorise the clinical severity of the stenoses. All patients underwent tracheal resection with primary end to end anastomosis. The length of cervical tracheal stenosis ranged from 2.3 to 4.1 cm. Grade II stenosis was present in three patients, Grade III stenosis was present in seven patients and grade IV stenosis in two patients. Successful extubation was achieved in all 12 cases. After surgery, temporary hoarseness occurred in 1 patient (8.3%); unilateral pulmonary atelectasis with pleural effusion occurred in 1 patient (8.3%); subcutaneous emphysema with infection occurred in 1 patient (8.3%); mild dysphagia occurred in 3 patients (25.0%); a slight deepening of the tone of voice occurred in 5 patients (41.7%), granulation tissue growth near the suture occurred in 3 patients (25.0%), and suture dehiscence did not occur in any patient. The follow-up period ranged from 6 months to 38 months, no patient developed restenosis. It presents a high success rate and good functional result of tracheal resection with primary end-to-end anastomosis. Therefore, it is an effective and reliable approach for the management of benign cervical tracheal stenosis. To avoid complications, the preoperative assessment, patients selection and postoperative management should be emphasized.

  20. Controls on anastomosis in lowland river systems: Towards process-based solutions to habitat conservation.

    Science.gov (United States)

    Marcinkowski, Paweł; Grabowski, Robert C; Okruszko, Tomasz

    2017-12-31

    Anastomosing rivers were historically common around the world before extensive agricultural and industrial development in river valleys. Few lowland anastomosing rivers remain in temperate zones, and the protection of these river-floodplain systems is an international conservation priority. However, the mechanisms that drive the creation and maintenance of multiple channels, i.e. anabranches, are not well understood, particularly for lowland rivers, making it challenging to identify effective management strategies. This study uses a novel multi-scale, process-based hydro-geomorphological approach to investigate the natural and anthropogenic controls on anastomosis in lowland river reaches. Using a wide range of data (hydrologic, cartographic, remote-sensing, historical), the study (i) quantifies changes in the planform of the River Narew, Poland over the last 100years, (ii) documents changes in the natural and anthropogenic factors that could be driving the geomorphic change, and (iii) develops a conceptual model of the controls of anastomosis. The results show that 110km of anabranches have been lost from the Narew National Park (6810ha), a 42% reduction in total anabranch length since 1900. The rates of anabranch loss have increased as the number of pressures inhibiting anabranch creation and maintenance has multiplied. The cessation of localized water level and channel management (fishing dams, water mills and timber rafting), the loss of traditional floodplain activities (seasonal mowing) and infrastructure construction (embanked roads and an upstream dam) are contributing to low water levels and flows, the deposition of sediment at anabranch inlets, the encroachment of common reed (Phragmites australis), and the eventual loss of anabranches. By identifying the processes driving the loss of anabranches, this study provides transferable insights into the controls of anastomosis in lowland rivers and the management solutions needed to preserve the unique

  1. First-line tracheal resection and primary anastomosis for postintubation tracheal stenosis.

    Science.gov (United States)

    Elsayed, H; Mostafa, A M; Soliman, S; Shoukry, T; El-Nori, A A; El-Bawab, H Y

    2016-07-01

    Introduction Tracheal stenosis following intubation is the most common indication for tracheal resection and reconstruction. Endoscopic dilation is almost always associated with recurrence. This study investigated first-line surgical resection and anastomosis performed in fit patients presenting with postintubation tracheal stenosis. Methods Between February 2011 and November 2014, a prospective study was performed involving patients who underwent first-line tracheal resection and primary anastomosis after presenting with postintubation tracheal stenosis. Results A total of 30 patients (20 male) were operated on. The median age was 23.5 years (range: 13-77 years). Seventeen patients (56.7%) had had previous endoscopic tracheal dilation, four (13.3%) had had tracheal stents inserted prior to surgery and one (3.3%) had undergone previous tracheal resection. Nineteen patients (63.3%) had had a tracheostomy. Eight patients (26.7%) had had no previous tracheal interventions. The median time of intubation in those developing tracheal stenosis was 20.5 days (range: 0-45 days). The median length of hospital stay was 10.5 days (range: 7-21 days). The success rate for anastomoses was 96.7% (29/30). One patient needed a permanent tracheostomy. The in-hospital mortality rate was 3.3%: 1 patient died from a chest infection 21 days after surgery. There was no mortality or morbidity in the group undergoing first-line surgery for de novo tracheal lesions. Conclusions First-line tracheal resection with primary anastomosis is a safe option for the treatment of tracheal stenosis following intubation and obviates the need for repeated dilations. Endoscopic dilation should be reserved for those patients with significant co-morbidities or as a temporary measure in non-equipped centres.

  2. Isentropic Compression of Argon

    International Nuclear Information System (INIS)

    Oona, H.; Solem, J.C.; Veeser, L.R.; Ekdahl, C.A.; Rodriquez, P.J.; Younger, S.M.; Lewis, W.; Turley, W.D.

    1997-01-01

    We are studying the transition of argon from an insulator to a conductor by compressing the frozen gas isentropically to pressures at which neighboring atomic orbitals overlap sufficiently to allow some electron motion between atoms. Argon and the other rare gases have closed electron shells and therefore remain montomic, even when they solidify. Their simple structure makes it likely that any measured change in conductivity is due to changes in the atomic structure, not in molecular configuration. As the crystal is compressed the band gap closes, allowing increased conductivity. We have begun research to determine the conductivity at high pressures, and it is our intention to determine the compression at which the crystal becomes a metal

  3. Pulsed Compression Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Roestenberg, T. [University of Twente, Enschede (Netherlands)

    2012-06-07

    The advantages of the Pulsed Compression Reactor (PCR) over the internal combustion engine-type chemical reactors are briefly discussed. Over the last four years a project concerning the fundamentals of the PCR technology has been performed by the University of Twente, Enschede, Netherlands. In order to assess the feasibility of the application of the PCR principle for the conversion methane to syngas, several fundamental questions needed to be answered. Two important questions that relate to the applicability of the PCR for any process are: how large is the heat transfer rate from a rapidly compressed and expanded volume of gas, and how does this heat transfer rate compare to energy contained in the compressed gas? And: can stable operation with a completely free piston as it is intended with the PCR be achieved?.

  4. Medullary compression syndrome

    International Nuclear Information System (INIS)

    Barriga T, L.; Echegaray, A.; Zaharia, M.; Pinillos A, L.; Moscol, A.; Barriga T, O.; Heredia Z, A.

    1994-01-01

    The authors made a retrospective study in 105 patients treated in the Radiotherapy Department of the National Institute of Neoplasmic Diseases from 1973 to 1992. The objective of this evaluation was to determine the influence of radiotherapy in patients with medullary compression syndrome in aspects concerning pain palliation and improvement of functional impairment. Treatment sheets of patients with medullary compression were revised: 32 out of 39 of patients (82%) came to hospital by their own means and continued walking after treatment, 8 out of 66 patients (12%) who came in a wheelchair or were bedridden, could mobilize by their own after treatment, 41 patients (64%) had partial alleviation of pain after treatment. In those who came by their own means and did not change their characteristics, functional improvement was observed. It is concluded that radiotherapy offers palliative benefit in patients with medullary compression syndrome. (authors). 20 refs., 5 figs., 6 tabs

  5. Rapid reconnection in compressible plasma

    International Nuclear Information System (INIS)

    Heyn, M.F.; Semenov, V.S.

    1996-01-01

    A study of set-up, propagation, and interaction of non-linear and linear magnetohydrodynamic waves driven by magnetic reconnection is presented. The source term of the waves generated by magnetic reconnection is obtained explicitly in terms of the initial background conditions and the local reconnection electric field. The non-linear solution of the problem found earlier, serves as a basis for formulation and extensive investigation of the corresponding linear initial-boundary value problem of compressible magnetohydrodynamics. In plane geometry, the Green close-quote s function of the problem is obtained and its properties are discussed. For the numerical evaluation it turns out that a specific choice of the integration contour in the complex plane of phase velocities is much more effective than the convolution with the real Green close-quote s function. Many complex effects like intrinsic wave coupling, anisotropic propagation characteristics, generation of surface and side wave modes in a finite beta plasma are retained in this analysis. copyright 1996 American Institute of Physics

  6. Action of matrix metalloproteinases at restricted sites in colon anastomosis repair

    DEFF Research Database (Denmark)

    Ågran, Magnus S.; Levin Andersen, Thomas; Mirastschijski, Ursula

    2006-01-01

    compared with adjacent micro-areas of 3-day-old anastomoses. Only this specific tissue compartment underwent a dramatic and significant increase in collagenolysis, amounting to a loss of 10% of existing collagen molecules in 24 hours, and was abolished by metalloproteinase inhibitors. The tissue....... CONCLUSIONS: The unique finding of this study was that the specific tissue holding the sutures of a colon anastomosis lost the most collagen presumably through induction and activation of multiple MMPs that may explain the beneficial effects of treatment with non-selective MMP antagonists....

  7. Factors affecting anastomotic leak after colorectal anastomosis in patients without protective stoma in tertiary care hospital

    International Nuclear Information System (INIS)

    Sultan, R.; Chawla, T.; Zaidi, M.

    2014-01-01

    Objective: To determine the factors associated with clinically significant anastomotic leak in patients having undergone large intestinal anastomosis. Method: The retrospective study at the Aga Khan University Hospital, Karachi, comprised data between January 2000 and March 2010, related to patients who underwent colorectal anastomosis. Demographic details of the patients, as well as preop, intraop and postop risk factors were recorded. Anastomotic leak was identified as per the defined criteria. Outcome of patients was recorded as postop hospital stay and mortality. Univariate and Multivariate analyses were applied to identify risk factors for anastomotic leakage. Results: Among the total 127 patients in the study, anastomotic leak occurred in 19 (15%) patients (Group 1), while there was no clinical leak in 108 (85%) patients (Group 2). Univariate analysis showed 8 factors to be affecting the anastomotic leak: operation time (p=0.003), intraoperative blood loss (p=0.006), intraoperative blood transfusion (p=0.013), indication of surgery malignancy vs. benign (p=0.049), type of surgery elective vs. emergency (p=0.037), intraop use of vasopressor (p=0.019), segment of bowel anastomosed left side vs. right side (p=0.012), and drain placement vs. no drain placed (p=0.035). Preop immunosuppressive therapy was borderline significant (p=0.089). Multivariate analysis showed that left vs. right sided anastomosis (p=0.068), blood transfusion >2 pack cells (p=0.028), smoker vs. non-smoker (p=0.049), elective vs. emergency surgery (p=0.012) were the independent risk factors which significantly affected the outcome of bowel anastomosis. Mortality rate was 15.79% (n=3/19) in Group 1, while it was 1.85% (n=2/108) in Group 2 (p=0.02). The postop hospital stay was 15+-5.44 days in Group 1, while it was 7.51+-4.04 days in Group 2 (p>0.001). Conclusion: In colorectal anastomotic surgeries temporary diversion stoma formation needs to be considered on the basis of risk factors to

  8. Computational fluid dynamic evaluation of the side-to-side anastomosis for arteriovenous fistula.

    Science.gov (United States)

    Hull, Jeffrey E; Balakin, Boris V; Kellerman, Brad M; Wrolstad, David K

    2013-07-01

    The goal of this research was to compare side-to-side (STS) and end-to-side (ETS) anastomoses in a computer model of the arteriovenous fistula with computational fluid dynamic analysis. A matrix of 17 computer arteriovenous fistula models (SolidWorks, Dassault Systèmes, France) of artery-vein pairs (3-mm-diameter artery + 3-mm-diameter vein and 4-mm-diameter artery +6-mm-diameter vein elliptical anastomoses) in STS, 45° ETS, and 90° ETS configurations with cross-sectional areas (CSAs) of 3.5 to 18.8 mm(2) were evaluated with computational fluid dynamic software (STAR-CCM+; CD-adapco, Melville, NY) in simulations at defined flow rates from 600 to 1200 mL/min and mean arterial pressures of 50 to 140 mm Hg. Models and configurations were evaluated for pressure drop across the anastomosis, arterial inflow, venous outflow, arterial outflow, velocity vector, and wall shear stress (WSS) profile. Pressure drop across the anastomosis was inversely proportional to anastomotic CSA and to venous outflow and was proportional to arterial inflow. Pressure drop was greater in 3 + 3 models than in 4 + 6 STS models; 90° ETS configurations had the lowest pressure drops and were nearly identical, whereas 45° ETS configurations had the highest pressure drops. Venous outflow in the 4 + 6 model in STS configurations, evaluated at 100 mm Hg arterial inflow pressure, was 390, 592, 610, and 886 mL/min in anastomotic CSAs of 3.5, 5.3, 7.1, and 18.8 mm(2), respectively, and was similar in 90° ETS (609 and 908 mL/min) and lower in 45° ETS (534 and 562 mL/min) configurations at CSAs of 5.3 and 18.8 mm(2). The mean increase in venous outflow was 69 mL/min (range, -59 to 134) between 3 + 3 and 4 + 6 models at 100 mm Hg arterial inflow. The most uniform WSS profile occurs in STS anastomoses followed by 45° ETS and then 90° ETS anastomoses. The STS and 90° ETS anastomoses have high venous outflow and a tendency toward reversed arterial outflow. The 45° ETS anastomosis has reduced venous

  9. Autologous Latissimus Dorsi Breast Reconstruction Flap Salvage: Microvascular Anastomosis with Serratus Branch

    Directory of Open Access Journals (Sweden)

    Victoria Kuta, BScH

    2017-07-01

    Full Text Available Summary:. Autologous breast reconstruction has become a standard option during the recovery of breast cancer survivors. Although pedicle damage is a rare complication of this procedure, extensive torsion or tension can lead to partial or total flap failure. We report a case of partial flap salvage after accidental transection of the pedicled blood supply within the intramuscular course of a latissimus dorsi musculocutaneous flap. This salvage technique involved microvascular anastomosis between the remaining vasculature of the latissimus dorsi pedicle and the serratus branch of the thoracodorsal artery and vein.

  10. Preoperative chemoradiotherapy and colonic J-pouch anal anastomosis for lower rectal cancer

    International Nuclear Information System (INIS)

    Inoue, Yasuhiro; Okigami, Masato; Kawamoto, Aya; Hiro, Junichiro; Toiyama, Yuji; Kobayashi, Minako; Tanaka, Koji; Miki, Chikao; Kusunoki, Masato

    2011-01-01

    We performed colonic J-pouch anal anastomosis in 61 patients with rectal cancer located <4 cm from the anal verge. Surgical and oncological results were evaluated in multimodality therapy for advanced rectal cancer. According to Wexner's score, 7% of patients were fully continent, 71% had acceptable function with minor continence problems, and 22% were incontinent. No patients required intermittent self-catheterization during follow-up. After a median follow-up of 49 months, there was only 1 case of local recurrence after surgery. Our surgical approach irrespective of internal sphincter resection produces satisfactory functional and oncological results in multimodality therapy using preoperative chemoradiotherapy for lower rectal cancer. (author)

  11. Laparoscopic resection of lower rectal cancer with telescopic anastomosis without abdominal incisions.

    Science.gov (United States)

    Li, Shi-Yong; Chen, Gang; Du, Jun-Feng; Chen, Guang; Wei, Xiao-Jun; Cui, Wei; Zuo, Fu-Yi; Yu, Bo; Dong, Xing; Ji, Xi-Qing; Yuan, Qiang

    2015-04-28

    To assess laparoscopic radical resection of lower rectal cancer with telescopic anastomosis through transanal resection without abdominal incisions. From March 2010 to June 2014, 30 patients (14 men and 16 women, aged 36-78 years, mean age 59.8 years) underwent laparoscopic radical resection of lower rectal cancer with telescopic anastomosis through anus-preserving transanal resection. The tumors were 5-7 cm away from the anal margin in 24 cases, and 4 cm in six cases. In preoperative assessment, there were 21 cases of T1N0M0 and nine of T2N0M0. Through the middle approach, the sigmoid mesentery was freed at the root with an ultrasonic scalpel and the roots of the inferior mesenteric artery and vein were dissected, clamped and cut. Following the total mesorectal excision principle, the rectum was separated until the anorectal ring reached 3-5 cm from the distal end of the tumor. For perineal surgery, a ring incision was made 2 cm above the dentate line, and sharp dissection was performed submucosally towards the superior direction, until the plane of the levator ani muscle, to transect the rectum. The rectum and distal sigmoid colon were removed together from the anus, followed by a telescopic anastomosis between the full thickness of the proximal colon and the mucosa and submucosal tissue of the rectum. For the present cohort of 30 cases, the mean operative time was 178 min, with an average of 13 positive lymph nodes detected. One case of postoperative anastomotic leak was observed, requiring temporary colostomy, which was closed and recovered 3 mo later. The postoperative pathology showed T1-T2N0M0 in 19 cases and T2N1M0 in 11 cases. Twelve months after surgery, 94.4% patients achieved anal function Kirwan grade 1, indicating that their anal function returned to normal. The patients were followed up for 1-36 mo, with an average of 23 mo. There was no local recurrence, and 17 patients survived for > 3 years (with a survival rate of 100%). Laparoscopic radical

  12. [Stomach and intestinal function after Bilroth-II resection with modified transversal anastomosis].

    Science.gov (United States)

    Zaĭtsev, V T; Egorov, I V; Grigorian, G O

    1994-01-01

    The functional peculiarities of transversal gastrointestinal anastomosis performed according to the modified method was investigated with the help of radiological method in 16 mongrel dogs, whom the stomach resection according to Bilroth-II was conducted. The emptying of gastric stump contents occurred in time with small portions. Its reflux into the afferent loop of intestine was not noted. The small intestine filling in was regular all the way. Complete restoration of motor-evacuating function of gastric stump and transit of contents down the small intestine loops was caused by the conduction of the proposed operative procedure.

  13. Absence of the genicular arterial anastomosis as generally depicted in textbooks.

    Science.gov (United States)

    Sabalbal, M; Johnson, M; McAlister, V

    2013-09-01

    Textbook representations of the genicular arterial anastomosis show a large direct communication between the descending branch of the lateral circumflex femoral artery (DBLCFA) and a genicular branch of the popliteal artery but this is not compatible with clinical experience. The aim of this study was to determine whether the arterial anastomosis at the knee is sufficient, in the event of traumatic disruption of the superficial femoral artery, to infuse protective agents or to place a stent to restore flow to the lower leg. Dissection of ten cadaveric lower limbs was performed to photograph the arterial anatomy from the inguinal ligament to the tibial tubercle. Anastomosis with branches of the popliteal artery was classified as: 'direct communication', 'approaching communication' or 'no evident communication'. A constant descending artery in the lateral thigh (LDAT) was found to have five types of origin: Type 1 (2/10 limbs) involved the lateral circumflex femoral branch of the femoral artery, Type 2 (3/10 limbs) the lateral circumflex femoral branch of the profunda femoris artery, Type 3 (1/10 limbs) the femoral artery, Type 4 (3/10 limbs) the superficial femoral artery and Type 5 (2/10 limbs) the profunda femoris artery. In one limb, there were two descending arteries (Types 4 and 5). Collateral circulation at the knee was also variable: direct communicating vessels (3/10 limbs); approaching vessels with possible communication via capillaries (5/10 limbs); no evident communication (2/10 limbs). Communicating vessels, if present, are too small to provide immediate collateral circulation. Modern representations of the genicular arterial anastomosis are inaccurate, derived commonly from an idealised image that first appeared Gray's Anatomy in 1910. The afferent vessel is not the DBLCFA. The majority of subjects have the potential to recruit collateral circulation via the LDAT following gradual obstruction to normal arterial flow, which may be important if the LDAT

  14. Intracorporeal Ileocolic Anastomosis in Laparoscopic Right Colectomy: A New Way to Make it Simple?

    Science.gov (United States)

    Rossini, Roberto; Lisi, Giorgio; Gentile, Irene; Barugola, Giuliano; Ruffo, Giacomo

    2018-03-29

    Although there has been a recent increase in the use of laparoscopy in colorectal surgery, the percentage of patients who undergo surgery using entirely minimally invasive techniques is still quite low, and there are substantial differences among centers. It has been argued that the limiting factor in the use of laparoscopic procedures is not the tumor or patient characteristics, but rather the number of surgeons with adequate skills to perform an entirely laparoscopic colectomy. To address this issue, we report here our totally laparoscopic right colectomy technique, with particular focus on a new way to perform the enterotomy closure, which may simplify ileocolic anastomosis.

  15. Ovarian cancer mimicking recurrence at colorectal anastomosis: report of a case.

    LENUS (Irish Health Repository)

    Reardon, C M

    2012-02-03

    PURPOSE: The aim of this article is to emphasize the increased risk of developing metachronous ovarian tumors after resection of rectal cancer. METHOD AND RESULTS: We report the case of a postmenopausal female patient who, five years after anterior resection, developed a primary ovarian malignancy that invaded a rectal anastomosis and in so doing mimicked a recurrence of a Dukes A rectal cancer. To our knowledge, such an occurrence has not been described previously in the literature. CONCLUSION: This case illustrates the possible benefits of routine prophylactic oophorectomy at the time of colorectal cancer resection.

  16. An efficient algorithm for MR image reconstruction and compression

    International Nuclear Information System (INIS)

    Wang, Hang; Rosenfeld, D.; Braun, M.; Yan, Hong

    1992-01-01

    In magnetic resonance imaging (MRI), the original data are sampled in the spatial frequency domain. The sampled data thus constitute a set of discrete Fourier transform (DFT) coefficients. The image is usually reconstructed by taking inverse DFT. The image data may then be efficiently compressed using the discrete cosine transform (DCT). A method of using DCT to treat the sampled data is presented which combines two procedures, image reconstruction and data compression. This method may be particularly useful in medical picture archiving and communication systems where both image reconstruction and compression are important issues. 11 refs., 3 figs

  17. Compression of toroidal plasma by imploding plasma-liner

    International Nuclear Information System (INIS)

    Ikuta, Kazunari.

    1979-07-01

    A new concept of compressing a plasma in a closed magnetic configuration by a version of liner implosion flux compression technique is considered. The liner consists of a dense plasma cylinder, i.e. the plasma-liner. Maximum compression ratio of toroidal plasma is determined just by the initial density ratio of the toroidal plasma to the liner plasma because of the Rayleigh-Taylor instability. A start-up senario of plasma-liner is also proposed with a possible application of this concept to the creation of a burning plasma in reversed field configurations, i.e. burning plasma vortex. (author)

  18. The role of diagnostic radiology in compressive and entrapment neuropathies

    International Nuclear Information System (INIS)

    Spratt, J.D.; Stanley, A.J.; Hide, I.G.; Campbell, R.S.D.; Grainger, A.J.

    2002-01-01

    Diagnostic imaging is increasingly being utilised to aid the diagnosis of compression and entrapment neuropathies. Cross-sectional imaging, primarily ultrasound and magnetic resonance imaging, can provide exquisite anatomical detail of peripheral nerves and the changes that may occur as a result of compression. Imaging can provide a useful diagnostic aid to clinicians, which may supplement clinical evaluation, and may eventually provide an alternative to other diagnostic techniques such as nerve conduction studies. This article describes the abnormalities that may be demonstrated by current imaging techniques, and critically analyses the impact of imaging in diagnosis of peripheral compressive neuropathy. (orig.)

  19. The role of diagnostic radiology in compressive and entrapment neuropathies

    Energy Technology Data Exchange (ETDEWEB)

    Spratt, J.D.; Stanley, A.J.; Hide, I.G.; Campbell, R.S.D. [Department of Radiology, James Cook University Hospital, Middlesbrough, TS4 3BW (United Kingdom); Grainger, A.J. [Department of Radiology, Leeds General Infirmary, Leeds (United Kingdom)

    2002-09-01

    Diagnostic imaging is increasingly being utilised to aid the diagnosis of compression and entrapment neuropathies. Cross-sectional imaging, primarily ultrasound and magnetic resonance imaging, can provide exquisite anatomical detail of peripheral nerves and the changes that may occur as a result of compression. Imaging can provide a useful diagnostic aid to clinicians, which may supplement clinical evaluation, and may eventually provide an alternative to other diagnostic techniques such as nerve conduction studies. This article describes the abnormalities that may be demonstrated by current imaging techniques, and critically analyses the impact of imaging in diagnosis of peripheral compressive neuropathy. (orig.)

  20. Graph Compression by BFS

    Directory of Open Access Journals (Sweden)

    Alberto Apostolico

    2009-08-01

    Full Text Available The Web Graph is a large-scale graph that does not fit in main memory, so that lossless compression methods have been proposed for it. This paper introduces a compression scheme that combines efficient storage with fast retrieval for the information in a node. The scheme exploits the properties of the Web Graph without assuming an ordering of the URLs, so that it may be applied to more general graphs. Tests on some datasets of use achieve space savings of about 10% over existing methods.

  1. Compression of magnetohydrodynamic simulation data using singular value decomposition

    International Nuclear Information System (INIS)

    Castillo Negrete, D. del; Hirshman, S.P.; Spong, D.A.; D'Azevedo, E.F.

    2007-01-01

    Numerical calculations of magnetic and flow fields in magnetohydrodynamic (MHD) simulations can result in extensive data sets. Particle-based calculations in these MHD fields, needed to provide closure relations for the MHD equations, will require communication of this data to multiple processors and rapid interpolation at numerous particle orbit positions. To facilitate this analysis it is advantageous to compress the data using singular value decomposition (SVD, or principal orthogonal decomposition, POD) methods. As an example of the compression technique, SVD is applied to magnetic field data arising from a dynamic nonlinear MHD code. The performance of the SVD compression algorithm is analyzed by calculating Poincare plots for electron orbits in a three-dimensional magnetic field and comparing the results with uncompressed data

  2. Tracheal anastomosis with the diode laser and fibrin tissue adhesive: an in vitro and in vivo investigation.

    Science.gov (United States)

    Gleich, L L; Wang, Z; Pankratov, M M; Aretz, H T; Shapshay, S M

    1995-05-01

    Absorbable sutures have been advocated for tracheal anastomosis to reduce fibrosis and foreign body reaction leading to recurrent stenosis. Fibrin tissue adhesive (FTA) and diode laser welding with indocyanine green-dyed fibrinogen were evaluated in tracheal anastomosis to reduce the number of sutures and to improve healing. In vitro studies demonstrated strong anastomoses with a combination of laser welding and FTA with minimal tissue damage. In a controlled in vivo study, circumferential resections of canine tracheas were repaired with laser welding and FTA augmented with a few stay sutures. These anastomoses had less fibrosis and tissue damage than anastomoses in control animals repaired with sutures alone. This study supports investigation of laser welding and FTA in human beings for tracheal anastomosis and other procedures in which suturing may be difficult.

  3. Comparative evaluation of entero-anastomosis by inversion techniques with different suturing materials in bovine [Water buffalo

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S. C.P.; Khan, A. A.; Dass, L. L.; Sahay, P. N.; Jha, G. J.

    1985-07-01

    Single layer end-to-end inverted and everted techniques of entero-anastomosis were evaluated in sixteen male buffalo calves using silk and catgut sutures. All the animals of everting group showed areas of adhesion grossly, whereas it was only in three animals of inverting group. Histological evidences revealed a more uniform healing pattern in inversion group and radiography suggested comparatively greater degree of stenosis, but without functional impairment of intestinal lumen, than everting anastomosis. Connective tissue proliferation and mononuclear cell infiltrations were very minimal with silk suture whereas these were pronounced with catgut, irrespective of anastomotic technique. Thus inversion technique of anastomosis accomplished by single layer suturing with silk thread was ideal for enteroanastomosis in cattle.

  4. HVS-based medical image compression

    Energy Technology Data Exchange (ETDEWEB)

    Kai Xie [Institute of Image Processing and Pattern Recognition, Shanghai Jiaotong University, 200030 Shanghai (China)]. E-mail: xie_kai2001@sjtu.edu.cn; Jie Yang [Institute of Image Processing and Pattern Recognition, Shanghai Jiaotong University, 200030 Shanghai (China); Min Zhuyue [CREATIS-CNRS Research Unit 5515 and INSERM Unit 630, 69621 Villeurbanne (France); Liang Lixiao [Institute of Image Processing and Pattern Recognition, Shanghai Jiaotong University, 200030 Shanghai (China)

    2005-07-01

    Introduction: With the promotion and application of digital imaging technology in the medical domain, the amount of medical images has grown rapidly. However, the commonly used compression methods cannot acquire satisfying results. Methods: In this paper, according to the existed and stated experiments and conclusions, the lifting step approach is used for wavelet decomposition. The physical and anatomic structure of human vision is combined and the contrast sensitivity function (CSF) is introduced as the main research issue in human vision system (HVS), and then the main designing points of HVS model are presented. On the basis of multi-resolution analyses of wavelet transform, the paper applies HVS including the CSF characteristics to the inner correlation-removed transform and quantization in image and proposes a new HVS-based medical image compression model. Results: The experiments are done on the medical images including computed tomography (CT) and magnetic resonance imaging (MRI). At the same bit rate, the performance of SPIHT, with respect to the PSNR metric, is significantly higher than that of our algorithm. But the visual quality of the SPIHT-compressed image is roughly the same as that of the image compressed with our approach. Our algorithm obtains the same visual quality at lower bit rates and the coding/decoding time is less than that of SPIHT. Conclusions: The results show that under common objective conditions, our compression algorithm can achieve better subjective visual quality, and performs better than that of SPIHT in the aspects of compression ratios and coding/decoding time.

  5. HVS-based medical image compression

    International Nuclear Information System (INIS)

    Kai Xie; Jie Yang; Min Zhuyue; Liang Lixiao

    2005-01-01

    Introduction: With the promotion and application of digital imaging technology in the medical domain, the amount of medical images has grown rapidly. However, the commonly used compression methods cannot acquire satisfying results. Methods: In this paper, according to the existed and stated experiments and conclusions, the lifting step approach is used for wavelet decomposition. The physical and anatomic structure of human vision is combined and the contrast sensitivity function (CSF) is introduced as the main research issue in human vision system (HVS), and then the main designing points of HVS model are presented. On the basis of multi-resolution analyses of wavelet transform, the paper applies HVS including the CSF characteristics to the inner correlation-removed transform and quantization in image and proposes a new HVS-based medical image compression model. Results: The experiments are done on the medical images including computed tomography (CT) and magnetic resonance imaging (MRI). At the same bit rate, the performance of SPIHT, with respect to the PSNR metric, is significantly higher than that of our algorithm. But the visual quality of the SPIHT-compressed image is roughly the same as that of the image compressed with our approach. Our algorithm obtains the same visual quality at lower bit rates and the coding/decoding time is less than that of SPIHT. Conclusions: The results show that under common objective conditions, our compression algorithm can achieve better subjective visual quality, and performs better than that of SPIHT in the aspects of compression ratios and coding/decoding time

  6. Compact toroid formation, compression, and acceleration

    International Nuclear Information System (INIS)

    Degnan, J.H.; Bell, D.E.; Baca, G.P.; Dearborn, M.E.; Douglas, M.R.; Englert, S.E.; Englert, T.J.; Holmes, J.H.; Hussey, T.W.; Kiuttu, G.F.; Lehr, F.M.; Marklin, G.J.; Mullins, B.W.; Peterkin, R.E.; Price, D.W.; Roderick, N.F.; Ruden, E.L.; Turchi, P.J.; Coffey, S.K.; Seiler, S.W.; Bird, G.

    1992-01-01

    Research on the formation, compression, and acceleration of milligram Compact Toroids (CTs) will be discussed. This includes experiments with 2-stage coaxial gun discharges and calculations including 2D- MHD. The CTs are formed by 110 μf, 70 KV, 2 MA, 3 μs rise time discharges into 2 mg gas puffs in a 90 cm inner diameter, 7.6 cm gap coaxial gun with approximately 0.15 Tesla of radial-axial initial magnetic field. Reconnection at the neck of the toroidal magnetized plasma bubble extracted from the first stage gun forms the CT. Trapping, relaxation to a minimum energy Taylor state is observed with magnetic probe arrays. Low energy (few hundred KJ, 2 MA) acceleration in straight coaxial geometry, and high energy acceleration using a conical compression stage are discussed. The Phillips Laboratory 1,300 μf, 120 KV, 9.4 MJ SHIVA STAR capacitor bank is used for the acceleration discharge. The charging and triggering of the 36-module bank has been modified to permit use of any multiple of three modules. Highlights of fast photography, current, voltage, magnetic probe array, optical spectroscopy, interferometry, VUV, and higher energy radiation data and 2D-MHD calculations will be presented. Considerably more detail is presented in companion papers

  7. Similar Outcome After Colonic Pouch and Side-to-End Anastomosis in Low Anterior Resection for Rectal Cancer

    Science.gov (United States)

    Machado, Mikael; Nygren, Jonas; Goldman, Sven; Ljungqvist, Olle

    2003-01-01

    Objectives To compare a colonic J-pouch or a side-to-end anastomosis after low-anterior resection for rectal cancer with regard to functional and surgical outcome. Summary Background Data: A complication after restorative rectal surgery with a straight anastomosis is low- anterior resection syndrome with a postoperatively deteriorated anorectal function. The colonic J-reservoir is sometimes used with the purpose of reducing these symptoms. An alternative method is to use a simple side-to-end anastomosis. Methods: One-hundred patients with rectal cancer undergoing total mesorectal excision and colo-anal anastomosis were randomized to receive either a colonic pouch or a side-to-end anastomosis using the descending colon. Surgical results and complications were recorded. Patients were followed with a functional evaluation at 6 and 12 months postoperatively. Results: Fifty patients were randomized to each group. Patient characteristics in both groups were very similar regarding age, gender, tumor level, and Dukes’ stages. A large proportion of the patients received short-term preoperative radiotherapy (78%). There was no significant difference in surgical outcome between the 2 techniques with respect to anastomotic height (4 cm), perioperative blood loss (500 ml), hospital stay (11 days), postoperative complications, reoperations or pelvic sepsis rates. Comparing functional results in the 2 study groups, only the ability to evacuate the bowel in <15 minutes at 6 months reached a significant difference in favor of the pouch procedure. Conclusions: The data from this study show that either a colonic J-pouch or a side-to-end anastomosis performed on the descending colon in low-anterior resection with total mesorectal excision are methods that can be used with similar expected functional and surgical results. PMID:12894014

  8. Ex vivo proof-of-concept of end-to-end scaffold-enhanced laser-assisted vascular anastomosis of porcine arteries

    NARCIS (Netherlands)

    Pabittei, Dara R.; Heger, Michal; van Tuijl, Sjoerd; Simonet, Marc; de Boon, Wadim; van der Wal, Allard C.; Balm, Ron; de Mol, Bas A.

    2015-01-01

    The low welding strength of laser-assisted vascular anastomosis (LAVA) has hampered the clinical application of LAVA as an alternative to suture anastomosis. To improve welding strength, LAVA in combination with solder and polymeric scaffolds (ssLAVA) has been optimized in vitro. Currently, ssLAVA

  9. Compressible generalized Newtonian fluids

    Czech Academy of Sciences Publication Activity Database

    Málek, Josef; Rajagopal, K.R.

    2010-01-01

    Roč. 61, č. 6 (2010), s. 1097-1110 ISSN 0044-2275 Institutional research plan: CEZ:AV0Z20760514 Keywords : power law fluid * uniform temperature * compressible fluid Subject RIV: BJ - Thermodynamics Impact factor: 1.290, year: 2010

  10. Temporal compressive sensing systems

    Science.gov (United States)

    Reed, Bryan W.

    2017-12-12

    Methods and systems for temporal compressive sensing are disclosed, where within each of one or more sensor array data acquisition periods, one or more sensor array measurement datasets comprising distinct linear combinations of time slice data are acquired, and where mathematical reconstruction allows for calculation of accurate representations of the individual time slice datasets.

  11. Compression of Infrared images

    DEFF Research Database (Denmark)

    Mantel, Claire; Forchhammer, Søren

    2017-01-01

    best for bits-per-pixel rates below 1.4 bpp, while HEVC obtains best performance in the range 1.4 to 6.5 bpp. The compression performance is also evaluated based on maximum errors. These results also show that HEVC can achieve a precision of 1°C with an average of 1.3 bpp....

  12. Gas compression infrared generator

    International Nuclear Information System (INIS)

    Hug, W.F.

    1980-01-01

    A molecular gas is compressed in a quasi-adiabatic manner to produce pulsed radiation during each compressor cycle when the pressure and temperature are sufficiently high, and part of the energy is recovered during the expansion phase, as defined in U.S. Pat. No. 3,751,666; characterized by use of a cylinder with a reciprocating piston as a compressor