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Sample records for catheters hollow needles

  1. Hollow needle used to cut metal honeycomb structures

    Science.gov (United States)

    Gregg, E. A.

    1966-01-01

    Hollow needle tool cuts metal honeycomb structures without damaging adjacent material. The hollow needle combines an electrostatic discharge and a stream of oxygen at a common point to effect rapid, accurate metal cutting. The tool design can be varied to use the hollow needle principle for cutting a variety of shapes.

  2. Hollow needle cataract aspiration in antiquity.

    Science.gov (United States)

    Pérez-Cambrodí, Rafael J; Ascaso, Francisco J; Diab, Fathi; Alzamora-Rodríguez, Antonio; Grzybowski, Andrzej

    2015-12-01

    The dislocation of the crystalline lens or couching technique was the predominant procedure to surgically remove cataracts until the 18th century A.D. However, in the Middle Ages, some Arab physicians tried to aspirate the opaque lens by means of a glass tube following a paracentesis. Some literary sources attributed the origins of this technique to Antyllus of Alexandria, a Greek surgeon who lived in the 2nd century A.D. in the Roman Empire. Nevertheless, this statement remains unclear and is probably the consequence of posterior interpretations or incorrect translations of the manuscripts. In recent years, the discovery of the hollow needles from Montbellet (France) and Viladamat (Spain), in archaeological settlements dated between the 1st century and 3rd century A.D., has reopened the possibility of cataract extraction as an option in the surgical management of soft cataracts in the antiquity. In any case, these findings are exceptional, and thus, probably this technique was not widely practised and very likely disparaged by the medical community. PMID:26385516

  3. Estimating needle-tissue interaction forces for hollow needles using fiber Bragg grating sensors

    Science.gov (United States)

    Kumar, Saurabh; Shrikanth, V.; Bharadwaj, Amrutur; Asokan, Sundarrajan; Bobji, M. S.

    2016-03-01

    Brachytherapy and neurological procedures can benefit from real-time estimation of needle-tissue interaction forces, specifically for robotic or robot-assisted procedures. Fiber Bragg Grating Sensors provide advantages of very small size and electromagnetic immunity for use in measurement of the forces directly at the needle tip. This has advantages compared to measurements at the needle shaft which require extensive models of the friction between needle and tissues with varying depth. This paper presents the measurement of tip forces for a hollow needle and compensation for bending when encountering regions of varying stiffness in phantoms with multiple layers prepared using Polydimethylsiloxane.

  4. A new modified technique of laparoscopic needle catheter jejunostomy: a 2-year follow-up study

    Directory of Open Access Journals (Sweden)

    Ye P

    2016-01-01

    Full Text Available Peng Ye, Liping Zeng, Fenghao Sun, Zhou An, Zhoubin Li, Jian Hu Department of Thoracic Surgery, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China Background: The aim of this study was to establish a modified technique for performing laparoscopic needle catheter jejunostomy. Methods: From May 2011 to October 2013, laparoscopic needle catheter jejunostomy was performed in 21 patients with esophageal cancer. During the procedure, jejunal inflation was performed via a percutaneous 20-gauge intravenous catheter to facilitate the subsequent puncture of the jejunal wall by the catheter needle. The success rate, procedure time, complications, and short-term outcomes were evaluated. Results: All laparoscopic needle catheter jejunostomies were technically successful, with no perioperative mortality or conversion to a laparotomy. The operation required a mean time of 51.4±14.2 (range 27–80 minutes, and operative bleeding range was 5–20 mL. There was one reoperation required for one patient on postoperative day 5, because the feeding tube was accidentally pulled out during sleep, by patient himself, and the second laparoscopic jejunostomy for this patient was performed successfully. One patient had puncture site pain and was successfully treated with oral analgesics. Other complications, such as gastrointestinal bleeding, intestinal perforation, intestinal obstruction, tube dysfunction, pericatheter leakage, and infection at the skin insertion site, were not observed. The 30-day mortality rate was 4.8% (one out of 21, which was not attributed to the procedure. Enteral nutrition was gradually administered 24–48 hours after operation. Conclusion: The novel modified technique of laparoscopic needle catheter jejunostomy is a technically feasible, with a high technical success rate and low complication rate. Its specific advantage is simplicity and safety, and this modified approach can be

  5. Ozone production of hollow-needle-to-mesh negative corona discharge enhanced by dielectric tube on the needle electrode

    International Nuclear Information System (INIS)

    For the hollow-needle-to-mesh negative corona discharge in air, we studied the effect of placing the dielectric tube on the needle electrode and the effect of various positions of the end of this tube with respect to the tip of the needle electrode on the concentration of ozone produced by the discharge, the ozone production yield and the discharge V–A characteristics. We found that the placement of the dielectric tube on the needle electrode with a suitable position of this tube end with respect to the tip of the needle electrode for a particular discharge power led to a more than fourfold increase in the concentration of ozone produced by the discharge and also, for a constant airflow, the ozone production yield. (fast track communication)

  6. Needle catheter jejunostomy: a controlled, prospective, randomized trial in patients with gynecologic malignancy.

    Science.gov (United States)

    Spirtos, N M; Ballon, S C

    1988-06-01

    Sixty patients with gynecologic cancer entered a prospective, randomized study of immediate postoperative feeding. Thirty-three women in the study group received an elemental diet (Vivonex HN) delivered through a needle catheter jejunostomy. Twenty-seven patients in the control group were given standard 5% dextrose and electrolyte solutions. Patients in both groups were stratified according to nutritional status as determined by anthropometric evaluation and levels of serum albumin, total protein, and transferrin. These parameters also were measured at intervals throughout the study. Only one catheter-related complication occurred. Patients in the study group received significantly more calories (p = 0.01) and were better able to maintain serum levels of transferrin (p = 0.05) than those in the control group. An elemental diet administered through the needle catheter jejunostomy effectively maintains postoperative nutrition and is associated with few complications. PMID:3132853

  7. Transconjunctival sutureless intrascleral intraocular lens fixation using intrascleral tunnels guided with catheter and 30-gauge needles.

    Science.gov (United States)

    Takayama, Kohei; Akimoto, Masayuki; Taguchi, Hogara; Nakagawa, Satoko; Hiroi, Kano

    2015-11-01

    We invented a new method for fixing an intraocular lens (IOL) in the scleral tunnel without using a wide conjunctival incision. Modified bent catheter needles were used to penetrate the IOL haptics through the sclerotomy sites. The IOL haptics were inserted into 30-guage (G) scleral tunnels guided by double 30-G needles piercing the sclera. All procedures were performed through the conjunctiva without wide incision. The procedure does not require special forceps, trocars or fibrin glue, only catheter and 30-G needles. The aid of an assistant was not required to support the IOL haptic. The procedures were easily learnt based on our previous method. As with other transconjunctival sutureless surgeries, patients feel less discomfort and the conjunctiva can be conserved for future glaucoma surgery. Complications included two cases of vitreous haemorrhage (16.7%), and one case each of postoperative hypotony, and iris capture (8.3%). Astigmatism induced by intraocular aberration was the same as we reported previously. Our method for fixing the IOL into the scleral tunnel is innovative, less expensive, less invasive and quick. This modified method is a good alternative for fixing IOL haptics into the sclera.

  8. Improved transvenous liver biopsy needle

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Matzen, P; Christoffersen, P;

    1979-01-01

    A modified type of the standard transvenous cholangiography biopsy needle is described. The modified tranvenous liver biopsy needle caused only minimal artefactual changes of the liver biopsy specimens. The new type of biopsy needle is a modified Menghini needle. The conventional Menghini needle...... should be avoided for transvenous catheter biopsies because of risk of leaving catheter fragments in the liver....

  9. Substituição da agulha isolada para eletroneuroestimulação pela agulha metálica de cateter intravenoso, na verificação da punção epidural, em cães Replacement of an insulated electric neurostimulation spinal needle with an intravenous catheter metal needle to confirm correct epidural puncture in dogs

    Directory of Open Access Journals (Sweden)

    E.A. Tudury

    2013-02-01

    Full Text Available Utilizou-se o eletroneuroestimulador como um meio adequado para confirmação do posicionamento da ponta de agulhas isoladas no espaço epidural lombossal, por meio de pequenas estimulações elétricas que provocam contrações dos músculos inervados, empregando-se agulha de cateter intravenoso em vez de agulha isolada para a eletroneuroestimulação. Foram utilizados 40 cães para procedimentos cirúrgicos ortopédicos, abdominais ou retroumbilicais que necessitassem de bloqueio epidural. Durante a introdução gradativa da agulha no canal vertebral lombossacral, estímulos elétricos de 1,5 a 0,5mA foram aplicados. Diante de contrações musculares em membros pélvicos, cauda e/ou ânus, as quais foram consideradas respostas condizentes com o correto posicionamento da agulha no espaço epidural, estimulando raízes da cauda equina, procedeu-se à administração da associação de lidocaína, bupivacaína e tramadol. Constatou-se a adequada anestesia epidural mediante relaxamento do esfíncter anal, ausência dos reflexos patelares e flexor e a analgesia na área cirúrgica abdominal. Conclui-se que o método foi eficaz para a confirmação do correto posicionamento da agulha no espaço epidural durante a realização dessa anestesia regional em cães.The electric neurostimulator was used as an adequate mean for the confirmation of the correct placement of the tip of the insulated needles in the lumbosacral epidural space through small electric stimulations causing muscle contractions by using an intravenous catheter needle instead of an electric neurostimulation insulated needle. Forty dogs were selected based on the need for an epidural block for orthopedic, abdominal or retroumbilical surgical procedures. Electrical stimuli were applied from 1.5 to 0.5mA during a gradual introduction of the needle into the lumbosacral vertebral canal. Responses that were considered as indicative of the correct placement of the needle and stimulation of

  10. Haemolyzed samples: responsibility of short catheters.

    Science.gov (United States)

    Raisky, F; Gauthier, C; Marchal, A; Blum, D

    1994-01-01

    The haemolysis of blood samples is a source of error in the electrolytic and enzymatic determination in clinical biochemistry. This circumstance seems dependent on the material used for the venepuncture. In this study we compared three kinds of material in 350 patients who were sampled in the emergency department. This randomized study compared the haemolysis of blood samples collected with stainless steel needles and short catheters, either Teflon FEP (Cathlon Critikon) or polyurethane Vialon (Insyte Becton-Dickinson). Quantification of hemolysis was performed by assay of the optical density of plasma haemoglobin. Results were analysed, after verification of the randomization, by one-way analysis of variance by ranks. This study demonstrated a highly significant relation between occurrence of haemolysis and the sampling material, used according to its technical obligations. Haemolysis occurred frequently when short catheters were used in 42% and 55% of cases with the Teflon and Vialon catheters, respectively. Haemolysis was much less frequent with stainless steel needles (12%). This difference was even more marked for haemoglobin levels above 1.5 milligrams of plasma, where the incidence was 4.2%, 9% and 30%, respectively, for the stainless steel needles, the Teflon catheter and the Vialon catheter. This study induced our emergency department to take more blood samples with a needle, even if an infusion was to be given subsequently, or to take them using a Teflon catheter. PMID:7840428

  11. Needles and Other Sharps (Safe Disposal Outside of Health Care Settings)

    Science.gov (United States)

    ... arthritis, cancer, diabetes, hepatitis, HIV/AIDS, infertility, migraines, multiple sclerosis, osteoporosis, blood clotting disorders, and psoriasis. Examples of sharps include: Needleshollow needles used to inject drugs (medication) under the skin Syringes – devices used to inject ...

  12. Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy

    International Nuclear Information System (INIS)

    In modern brachytherapy, application of large doses of ionizing radiation in a limited number of fractions is frequent. Furthermore, as with any surgical procedures, brachytherapy is subject to learning curve effects. In this context, there could be advantages of integrating real-time tracking of needles/catheters to existing protocols given the recent prominent advances in tracking technologies. In this work, we review the use of an electromagnetic tracking system (EMTS) based on the second generation Aurora® Planar Field Generator (Northern Digital Inc) and custom design needles (Philips Healthcare) for brachytherapy applications. The position and orientation information is obtained from 5 degrees of freedom sensors. Basic system performance characterization is performed in well-controlled conditions to establish accuracy and reproducibility as well as potential interference from standard brachytherapy equipment. The results show that sensor locations can be tracked to within 0.04mm (la) when located within 26cm of the generator. Orientation accuracy of the needle remained within ±1° in the same region, but rose quickly at larger distances. The errors on position and orientation strongly dependent the sensor position in the characterization volume (500×500×500mm3). The presence of an ultrasound probe was shown to have negligible effects on tracking accuracy. The use of EMTS for automatic catheter/applicator reconstruction was also explored. Reconstruction time was less than 10 sec/channel and tips identification was within 0.69±0.29mm of the reference values. Finally, we demonstrate that hollow needle designs with special EM adaptation also allow for real-time seed drop position estimation. In phantom experiments showed that drop positions were on average within 1.6±0.9mm of the reference position measured from μCT. Altogether, EMTS offer promising benefits in a wide range of brachytherapy applications

  13. Sci—Fri PM: Topics — 08: The Role and Benefits of Electromagnetic Needle-Tracking Technologies in Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Beaulieu, L.; Racine, E.; Boutaleb, S.; Filion, O. [Département de Radio-Oncologie et Centre de Recherche du CHU de Québec, CHU de Québec, Québec (Québec), and Département de Physique, de Génie Physique et d' Optique et Centre de recherche en sur le Cancer, Université Laval, Québec (Québec) (Canada); Poulin, E.; Hautvast, G. [Biomedical Systems, Philips Group Innovation, High Tech Campus 34 (HTC 34), Eindhoven (Netherlands); Binnekamp, D. [Integrated Clinical Solutions and Marketing, Philips Healthcare, Veenpluis 4-6, Best (Netherlands)

    2014-08-15

    In modern brachytherapy, application of large doses of ionizing radiation in a limited number of fractions is frequent. Furthermore, as with any surgical procedures, brachytherapy is subject to learning curve effects. In this context, there could be advantages of integrating real-time tracking of needles/catheters to existing protocols given the recent prominent advances in tracking technologies. In this work, we review the use of an electromagnetic tracking system (EMTS) based on the second generation Aurora® Planar Field Generator (Northern Digital Inc) and custom design needles (Philips Healthcare) for brachytherapy applications. The position and orientation information is obtained from 5 degrees of freedom sensors. Basic system performance characterization is performed in well-controlled conditions to establish accuracy and reproducibility as well as potential interference from standard brachytherapy equipment. The results show that sensor locations can be tracked to within 0.04mm (la) when located within 26cm of the generator. Orientation accuracy of the needle remained within ±1° in the same region, but rose quickly at larger distances. The errors on position and orientation strongly dependent the sensor position in the characterization volume (500×500×500mm{sup 3}). The presence of an ultrasound probe was shown to have negligible effects on tracking accuracy. The use of EMTS for automatic catheter/applicator reconstruction was also explored. Reconstruction time was less than 10 sec/channel and tips identification was within 0.69±0.29mm of the reference values. Finally, we demonstrate that hollow needle designs with special EM adaptation also allow for real-time seed drop position estimation. In phantom experiments showed that drop positions were on average within 1.6±0.9mm of the reference position measured from μCT. Altogether, EMTS offer promising benefits in a wide range of brachytherapy applications.

  14. Paraesthesia during the needle-through-needle and the double segment technique for combined spinal epidural anaesthesia.

    Science.gov (United States)

    Ahn, H J; Choi, D H; Kim, C S

    2006-07-01

    Paraesthesia during regional anaesthesia is an unpleasant sensation for patients and, more importantly, in some cases it is related to neurological injury. Relatively few studies have been conducted on the frequency of paraesthesia during combined spinal epidural anaesthesia. We compared two combined spinal epidural anaesthesia techniques: the needle-through-needle technique and the double segment technique in this respect. We randomly allocated 116 parturients undergoing elective Caesarean section to receive anaesthesia using one of these techniques. Both techniques were performed using a 27G pencil point needle, an 18G Tuohy needle, and a 20G multiport epidural catheter from the same manufacturer. The overall frequency of paraesthesia was higher in the needle-through-needle technique group (56.9% vs. 31.6%, p = 0.011). The frequency of paraesthesia at spinal needle insertion was 20.7% in the needle-through-needle technique group and 8.8% in the double segment technique group; whereas the frequency of paraesthesia at epidural catheter insertion was 46.6% in the needle-through-needle technique group and 24.6% in the double segment technique group.

  15. A novel suture method to place and adjust peripheral nerve catheters

    DEFF Research Database (Denmark)

    Rothe, C.; Steen-Hansen, C.; Madsen, M. H.;

    2015-01-01

    We have developed a peripheral nerve catheter, attached to a needle, which works like an adjustable suture. We used in-plane ultrasound guidance to place 45 catheters close to the femoral, saphenous, sciatic and distal tibial nerves in cadaver legs. We displaced catheters after their initial plac...... successful and 42/43 secondary placements successful by ultrasound, confirmed in 10/10 cases by magnetic resonance imaging....

  16. Advanced Imaging Catheter: Final Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Krulevitch, P; Colston, B; DaSilva, L; Hilken, D; Kluiwstra, J U; Lee, A P; London, R; Miles, R; Schumann, D; Seward, K; Wang, A

    2001-07-20

    Minimally invasive surgery (MIS) is an approach whereby procedures conventionally performed with large and potentially traumatic incisions are replaced by several tiny incisions through which specialized instruments are inserted. Early MIS, often called laparoscopic surgery, used video cameras and laparoscopes to visualize and control the medical devices, which were typically cutting or stapling tools. More recently, catheter-based procedures have become a fast growing sector of all surgeries. In these procedures, small incisions are made into one of the main arteries (e.g. femoral artery in the thigh), and a long thin hollow tube is inserted and positioned near the target area. The key advantage of this technique is that recovery time can be reduced from months to a matter of days. In the United States, over 700,000 catheter procedures are performed annually representing a market of over $350 million. Further growth in this area will require significant improvements in the current catheter technology. In order to effectively navigate a catheter through the tortuous vessels of the body, two capabilities must exist: imaging and positioning. In most cases, catheter procedures rely on radiography for visualization and manual manipulation for positioning of the device. Radiography provides two-dimensional, global images of the vasculature and cannot be used continuously due to radiation exposure to both the patient and physician. Intravascular ultrasound devices are available for continuous local imaging at the catheter tip, but these devices cannot be used simultaneously with therapeutic devices. Catheters are highly compliant devices, and manipulating the catheter is similar to pushing on a string. Often, a guide wire is used to help position the catheter, but this procedure has its own set of problems. Three characteristics are used to describe catheter maneuverability: (1) pushability -- the amount of linear displacement of the distal end (inside body) relative to

  17. Presternal peritoneal catheter.

    Science.gov (United States)

    Twardowski, Zbylut J

    2002-04-01

    The swan neck presternal catheter is composed of 2 flexible (silicon rubber) tubes joined by a titanium connector at the time of implantation. The exit site is located in the parasternal area. The catheter located on the chest was designed to reduce the incidence of exit site infections compared to peritoneal dialysis catheters with abdominal exits. From August 1991 to September 30, 2001, 974 swan neck presternal catheters were implanted worldwide. At the university of Missouri, 150 of these catheters were implanted and followed for over 130 patient years. Presternal catheters tended to perform better than swan neck abdominal catheters regarding exit and tunnel infections, even though they were implanted in several patients in whom regular catheters with the exit on the abdomen would be difficult or impossible to implant. Two-year survival probability of presternal catheters was 0.95. Recurrent/refractory peritonitis was the only reason for catheter failure. The catheter is particularly useful in obese patients (body mass index >35), patients with ostomies, children with diapers and fecal incontinence, and patients who want to take baths without the risk of exit contamination. Many patients prefer presternal catheter because of better body image. Disadvantages of the presternal catheter are minimal. Compared with abdominal catheters, dialysis-solution flow is slightly slower because of the increased catheter length; however, slower flow is insignificant clinically. There is a possibility of catheter disconnection in the tunnel, but this complication is extremely rare in adults and easily corrected. Finally, the implantation technique is more challenging compared with that of single-piece, abdominal catheters. PMID:12085389

  18. Central venous catheters and catheter locks in children with cancer

    DEFF Research Database (Denmark)

    Handrup, Mette Møller; Møller, Jens Kjølseth; Schrøder, Henrik

    2013-01-01

    To determine if the catheter lock taurolidine can reduce the number of catheter-related bloodstream infections (CRBSI) in pediatric cancer patients with tunneled central venous catheters (CVC).......To determine if the catheter lock taurolidine can reduce the number of catheter-related bloodstream infections (CRBSI) in pediatric cancer patients with tunneled central venous catheters (CVC)....

  19. Suprapubic catheter care

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000145.htm Suprapubic catheter care To use the sharing features on this page, please enable JavaScript. A suprapubic catheter (tube) drains urine from your bladder. It is ...

  20. Percutaneously inserted long-term central venous catheters in pigs of different sizes.

    Science.gov (United States)

    Larsson, N; Claesson Lingehall, H; Al Zaidi, N; Claesson, J; Jensen-Waern, M; Lehtipalo, S

    2015-07-01

    Pigs are used for long-term biomedical experiments requiring repeated injections, infusions and collections of blood samples. Thus, it is necessary for vascular catheters to be indwelling to avoid undue stress to the animals and the use of restraints. We propose a refined model of percutaneous insertion of long-term central venous catheters to minimize the surgical trauma and postoperative complications associated with catheter insertion. Different sizes of needles (18 Ga versus 21 Ga) for initial puncture of the veins were compared. In conventional pigs weighing less than 30 kg, catheter insertion may be facilitated by using a microintroducer set with a 21 Ga needle. In pigs weighing 50 kg, a standard 18 Ga needle may be preferable.

  1. Dosimetric equivalence of nonstandard HDR brachytherapy catheter patterns

    International Nuclear Information System (INIS)

    Purpose: To determine whether alternative high dose rate prostate brachytherapy catheter patterns can result in similar or improved dose distributions while providing better access and reducing trauma. Materials and Methods: Standard prostate cancer high dose rate brachytherapy uses a regular grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. This study used CT datasets with 3 mm slice spacing from ten previously treated patients and digitized new catheters following three hypothetical catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a plan must fulfill the RTOG-0321 dose criteria for target dose coverage (V100Prostate>90%) and organ-at-risk dose sparing (V75Bladder75Rectum125Urethra<<1 cc). Results: The three nonstandard catheter patterns used 16 nonparallel, straight divergent catheters, with entry points in the perineum. Thirty plans from ten patients with prostate sizes ranging from 26 to 89 cc were optimized. All nonstandard patterns fulfilled the RTOG criteria when the clinical plan did. In some cases, the dose distribution was improved by better sparing the organs-at-risk. Conclusion: Alternative catheter patterns can provide the physician with additional ways to treat patients previously considered unsuited for brachytherapy treatment (pubic arch interference) and facilitate robotic guidance of catheter insertion. In addition, alternative catheter patterns may

  2. Needle autopsy

    Directory of Open Access Journals (Sweden)

    Philip Davis Marsden

    1997-04-01

    Full Text Available Often in tropical practice there is not time or conditions to do a proper autopsy on a patient who has died. A needle biopsy technique is described for limited closed autopsy examination to clariffy organ histology. In this way the clinician may resolve puzzling fatal disease.Muitas vezes, em clínicas de países tropicais, não há tempo nem condições para se realizar uma necropsia adequada em um paciente que foi a óbito. Um técnica de biópsia por punção é descrita para fins de exame em necropsia limitadamente fechada, para esclarecimento da histologia do órgão. Dessa maneira, o clínico pode resolver enigmas de doenças fatais.

  3. Subcutaneous infusion: non-metal cannulae vs metal butterfly needles.

    Science.gov (United States)

    Torre, Maria Carrion

    2002-07-01

    This review aimed to evaluate the effectiveness of non-metal cannulae compared to metal butterfly needles in maintaining subcutaneous infusion sites in patients receiving palliative care. The Cochrane Library, Medline, Pre-Medline, Embase, CINAHL, Amed and Cancerlit were searched for relevant studies. Controlled trials comparing non-metal cannulae with metal butterfly needles for giving subcutaneous infusion to palliative care patients were included. The outcome considered was site duration in terms of hours of patency or until change was required. Four trials met the inclusion criteria although overall quality was poor due to low follow-up. Studies examined either Teflon or Vialon-coated catheters. All studies showed non-metal cannulae to be superior to metal. In individual studies estimates in mean increase in duration of the site range from 21 to 159 hours. It seems that non-metal cannulae are more effective in maintaining the duration of subcutaneous infusion sites than butterfly needles. Both types of non-metal catheter showed clear benefits. This review has not examined other outcomes but in general adverse effects lead to the removal of the catheter and so would be reflected in the outcome of considered. Although historically non-metal cannulae have been considerably more expensive there is now little difference between metal and Teflon-coated catheters. This review recommends the use of non-metal cannulae in preference to butterfly needles. PMID:12131852

  4. Interventional radiological imaging and treatment of port catheter dysfunctions; Angiografische Diagnostik und interventionelle Therapie von Portdysfunktionen

    Energy Technology Data Exchange (ETDEWEB)

    Kausche, S.; Nagel, S.N.; Teichgraeber, Ulf [Charite Universitaetsmedizin Berlin (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie

    2011-03-15

    To evaluate the impact of interventional radiological imaging and treatment of central venous port catheter complications. Materials and Methods: In this retrospective analysis 429 port catheter dysfunctions were evaluated in 393 port catheter systems for a total of 389 patients over a period of 10 years. The study included 193 (49.1 %) patients with radiologically implanted port catheter systems and 200 (50.9 %) referred patients with surgically implanted port systems. Port catheter dysfunctions were subdivided into early and late complications as well as into non-thrombotic and thrombotic events. After administration of contrast medium, the port system was visualized using digital subtraction angiography. Data were retrospectively collected from the in-house databases and then analyzed descriptively. Results: 429 contrast media injections via port catheters were performed in 393 port catheter systems. There were 359 (83.7 %) late complications and 70 (16.3 %) early complications. In 299 (69.7 %) cases thrombotic events occurred and 130 (30.3 %) non-thrombotic events were recorded. The most common reason for contrast media injection via port catheter system was port catheter-related thrombosis in 269 (62.7 %) cases. 70 (16.3 %) catheter migrations and 30 (7.0 %) fibrin sheath formations were detected. 18 (4.2 %) port needle malfunctions could be resolved through needle exchange. All 15 (3.5 %) catheter disconnections had to be revised in all cases. Also six port explantations were performed in 6 (1.4 %) catheter fractures. Conclusion: The possibilities of angiographic imaging and interventional radiological correction of port catheter dysfunctions must be exploited fully in order to avoid premature port explantation. (orig.)

  5. JUGULAR CENTRAL VENOUS CATHETER PLACEMENT THROUGH A MODIFIED SELDINGER TECHNIQUE FOR LONG-TERM VENOUS ACCESS IN CHELONIANS.

    Science.gov (United States)

    Pardo, Mariana A; Divers, Stephen

    2016-03-01

    Long-term or repeated venous access in chelonians is difficult to obtain and manage, but can be critically important for administration of medications and blood sampling in hospitalized patients. Jugular catheterization provides the most rapid and secure route for vascular access, but catheters can be difficult to place, and maintaining catheter patency may be challenging. Long multilumen polyurethane catheters provide flexibility and sampling access, and minimize difficulties, such as catheter displacement, that have been encountered with traditional over-the-needle catheters. We describe placement of 4 Fr. 13-cm polyurethane catheters in three chelonians with the use of a modified Seldinger technique. Venous access was obtained with the use of an over-the-needle catheter, which allowed placement of a 0.018-in.-diameter wire, over which the polyurethane catheter was placed. Indwelling time has ranged between 1 and 4 mo currently. All tortoises were sedated for this procedure. Polyurethane central catheters provide safe, long-term venous access that allows clinicians to perform serial blood sampling as well as intravenous administration of medications, anesthetic agents, and fluids. A jugular catheter can also allow central venous pressure measurement. Utilization of central line catheters was associated with improvements in diagnostic efficiency and therapeutic case management, with minimal risks and complications.

  6. Integer Programs for High Dose Rate Brachytherapy Needle and Dose Planning that Directly Optimize Clinical Objectives

    OpenAIRE

    Siauw, Ko-Ay Timmy

    2012-01-01

    High dose rate (HDR) brachytherapy is a radiation therapy for cancer in the prostate, cervix, breast, head, and neck, including other sites. In HDR brachytherapy, hollow needles are inserted or placed near the cancer site. Radiation is delivered to the patient by a radioactive source which is sequentially threaded through the needles. The dose distribution is controlled by altering the dwell times, the time spent at pre-defined positions on the needles.HDR brachytherapy has a 90\\% cancer-free...

  7. [Suprapubic catheter insertion].

    Science.gov (United States)

    Neumann, Eva; Schwentner, Christian

    2016-01-01

    The suprapubic catheter enables a percutaneous drainage of urine. The insertion is made superior of the pubic bone through the abdominal wall into the bladder. It allows a permanent drainage of urine bypassing the urethra. The insertion of a suprapubic catheter requires knowledge and expertise. This paper summarizes the basic background and allows to follow the practical application step by step. PMID:26800072

  8. Dosimetric equivalence of non-standard high dose rate (HDR) brachytherapy catheter patterns

    CERN Document Server

    Cunha, J Adam M; Pouliot, Jean

    2009-01-01

    Purpose: To determine whether alternative HDR prostate brachytherapy catheter patterns can result in improved dose distributions while providing better access and reducing trauma. Methods: Prostate HDR brachytherapy uses a grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. On CT data from ten previously-treated patients new catheters were digitized following three catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a p...

  9. Rectal extrusion of the catheter and air ventriculography following bowel perforation in ventriculo-peritoneal shunt

    Energy Technology Data Exchange (ETDEWEB)

    Arico, M.; Podesta, A.F.; Bianchi, E.; Beluffi, G.; Fiori, P.; Chiari, G.; Pezzotta, S.

    1985-01-01

    Ventriculo-peritoneal shunt is frequently carried out in infantile hydrocephalus. The peritoneal shunt has a lower morbidity than ventriculo-atrial shunt and severe complications are uncommon. Abdominal complications include intestinal perforation, shunt migration, inguinal hernia, cerebrospinal fluid pseudocysts and hollow viscus perforation. A few cases of catheter extrusion from the rectum, vagina, umbilicus and urethra have been described. We report a new case of intestinal perforation with rectal extrusion of the catheter associated with a ventriculogram.

  10. Auditing urinary catheter care.

    Science.gov (United States)

    Dailly, Sue

    Urinary catheters are the main cause of hospital-acquired urinary tract infections among inpatients. Healthcare staff can reduce the risk of patients developing an infection by ensuring they give evidence-based care and by removing the catheter as soon as it is no longer necessary. An audit conducted in a Hampshire hospital demonstrated there was poor documented evidence that best practice was being carried out. Therefore a urinary catheter assessment and monitoring tool was designed to promote best practice and produce clear evidence that care had been provided. PMID:22375340

  11. Comparison of metal versus Vialon subcutaneous catheters in a palliative care setting.

    Science.gov (United States)

    Currow, D; Cooney, N

    1994-10-01

    In 63 evaluable palliative care patients requiring intermittent bolus subcutaneous administration of medication, who were randomly assigned either a standard metal subcutaneous needle or a PTFE (Vialon) catheter, there was a significantly greater incidence of local reactions at the insertion site with the metal needles (9/30) compared with the PTFE catheters (2/33). Despite this, there was no significant difference between the two in functional survival. Volume of medication injected per day was the best predictor of total time that the subcutaneous lines remained in situ. PMID:7812483

  12. Needle Biopsy of the Lung

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Needle Biopsy of the Lung Needle biopsy of the lung ... Needle Biopsy of Lung Nodules? What is Needle Biopsy of the Lung? A lung nodule is relatively ...

  13. Effectiveness of a Drill-assisted Intraosseous Catheter versus Manual Intraosseous Catheter by Resident Physicians in a Swine Model

    Directory of Open Access Journals (Sweden)

    Hafner, John William

    2013-11-01

    Full Text Available Introduction: Our objective was to compare the effectiveness, speed, and complication rate of the traditional manually placed intraosseous (IO catheter to a mechanical drill-assisted IO catheter by emergency medicine (EM resident physicians in a training environment. Methods: Twenty-one EM residents participated in a randomized prospective crossover experiment placing 2 intraosseous needles (Cook® Intraosseous Needle, Cook Medical, Bloomington, IN; and EZ-IO® Infusion System, Vidacare, San Antonio, TX. IO needles were placed in anesthetized mixed breed swine (mass range: 25 kg to 27.2 kg. The order of IO placement and puncture location (proximal tibia or distal femur were randomly assigned. IO placement time was recorded from skin puncture until the operator felt they had achieved successful placement. We used 3 verification criteria: aspiration of marrow blood, easy infusion of 10 mL saline mixed with methylene blue, and lack of stained soft tissue extravasation. Successful placement was defined as meeting 2 out of the 3 predetermined criteria. We surveyed participants regarding previous IO experience, device preferences, and comfort levels using multiple choice, Likert scale, and visual analog scale (VAS questions. IO completion times, VAS, and mean Likert scales were compared using Student’s t-test and success rates were compared using Fisher’s exact test with p<0.05 considered significant.Results: Drill-assisted IO needle placement was faster than manually placed IO needle placement (3.66 vs. 33.57 seconds; p=0.01. Success rates were 100% with the drill-assisted IO needle and 76.2% with the manual IO needle (p=0.04. The most common complication of the manual IO insertion was a bent needle (33.3% of attempts. Participants surveyed preferred the drill-assisted IO insertion more than the manual IO insertion (p<0.0001 and felt the drill-assisted IO was easier to place (p<0.0001.Conclusion: In an experimental swine model, drill-assisted IO

  14. Dedicated radial ventriculography pigtail catheter

    Energy Technology Data Exchange (ETDEWEB)

    Vidovich, Mladen I., E-mail: miv@uic.edu

    2013-05-15

    A new dedicated cardiac ventriculography catheter was specifically designed for radial and upper arm arterial access approach. Two catheter configurations have been developed to facilitate retrograde crossing of the aortic valve and to conform to various subclavian, ascending aortic and left ventricular anatomies. The “short” dedicated radial ventriculography catheter is suited for horizontal ascending aortas, obese body habitus, short stature and small ventricular cavities. The “long” dedicated radial ventriculography catheter is suited for vertical ascending aortas, thin body habitus, tall stature and larger ventricular cavities. This new design allows for improved performance, faster and simpler insertion in the left ventricle which can reduce procedure time, radiation exposure and propensity for radial artery spasm due to excessive catheter manipulation. Two different catheter configurations allow for optimal catheter selection in a broad range of patient anatomies. The catheter is exceptionally stable during contrast power injection and provides equivalent cavity opacification to traditional femoral ventriculography catheter designs.

  15. Effects of insertion speed and trocar stiffness on the accuracy of needle position for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    McGill, Carl S.; Schwartz, Jonathon A.; Moore, Jason Z.; McLaughlin, Patrick W.; Shih, Albert J. [Biomedical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, State College, Pennsylvania 16802 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States); Biomedical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109 and Mechanical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2012-04-15

    Purpose: In prostate brachytherapy, accurate positioning of the needle tip to place radioactive seeds at its target site is critical for successful radiation treatment. During the procedure, needle deflection leads to seed misplacement and suboptimal radiation dose to cancerous cells. In practice, radiation oncologists commonly use high-speed hand needle insertion to minimize displacement of the prostate as well as the needle deflection. Effects of speed during needle insertion and stiffness of trocar (a solid rod inside the hollow cannula) on needle deflection are studied. Methods: Needle insertion experiments into phantom were performed using a 2{sup 2} factorial design (2 parameters at 2 levels), with each condition having replicates. Analysis of the deflection data included calculating the average, standard deviation, and analysis of variance (ANOVA) to find significant single and two-way interaction factors. Results: The stiffer tungsten carbide trocar is effective in reducing the average and standard deviation of needle deflection. The fast insertion speed together with the stiffer trocar generated the smallest average and standard deviation for needle deflection for almost all cases. Conclusions: The combination of stiff tungsten carbide trocar and fast needle insertion speed are important to decreasing needle deflection. The knowledge gained from this study can be used to improve the accuracy of needle insertion during brachytherapy procedures.

  16. Dosimetric equivalence of nonstandard HDR brachytherapy catheter patterns

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, J. A. M.; Hsu, I-C.; Pouliot, J. [University of California, San Francisco, California 94115 (United States)

    2009-01-15

    Purpose: To determine whether alternative high dose rate prostate brachytherapy catheter patterns can result in similar or improved dose distributions while providing better access and reducing trauma. Materials and Methods: Standard prostate cancer high dose rate brachytherapy uses a regular grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. This study used CT datasets with 3 mm slice spacing from ten previously treated patients and digitized new catheters following three hypothetical catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a plan must fulfill the RTOG-0321 dose criteria for target dose coverage (V{sub 100}{sup Prostate}>90%) and organ-at-risk dose sparing (V{sub 75}{sup Bladder}<1 cc, V{sub 75}{sup Rectum}<1 cc, V{sub 125}{sup Urethra}<<1 cc). Results: The three nonstandard catheter patterns used 16 nonparallel, straight divergent catheters, with entry points in the perineum. Thirty plans from ten patients with prostate sizes ranging from 26 to 89 cc were optimized. All nonstandard patterns fulfilled the RTOG criteria when the clinical plan did. In some cases, the dose distribution was improved by better sparing the organs-at-risk. Conclusion: Alternative catheter patterns can provide the physician with additional ways to treat patients previously considered unsuited for brachytherapy treatment (pubic arch interference) and facilitate robotic guidance of

  17. NURSING CARE IN PATIENTS NEONATES WITH PERIPHERALLY INSERTED CENTRAL CATHETER

    Directory of Open Access Journals (Sweden)

    Anacilda Oliveira Vieira

    2013-12-01

    Full Text Available Introduction: The PICC (peripherally inserted central catheter is a long flexible catheter which is inserted through a peripheral vein, progresses through a needle introducer until the final portion of the vena cava, acquiring characteristics of a central catheter. Objective: To point out the main theoretical and scientific ideas that demonstrate the reliability, competence and ability of nurses to perform the PICC. Methodology: Systematic review of articles, which were found by searching the database scientific journals and bibliographies area. Results: The success of integration depends on the patient assessment and choice of venous access where the catheter will be positioned, and its tip should be in the middle third of the superior vena cava, or the middle third of the inferior vena cava. In neonates, which are used more frequently, proper positioning of the catheter is through nursing care in making the dressing, and the first 24 hours it should be compressive. Ideally, the PICC remains in the vein for periods longer than seven days or until the end of treatment, thus decreasing invasive procedures. Conclusion: According to the Federal Board of Nursing (COFEN, it is lawful for the insertion of PICC nurses, provided it has undergone professional training.

  18. Central venous catheter insertion problem solving using intravenous catheter: technical communication

    Directory of Open Access Journals (Sweden)

    Alemohammad M

    2013-02-01

    Full Text Available Insertion of central venous catheter is an accepted method for hemodynamic monitor-ring, drug and fluid administration, intravenous access, hemodialysis and applying cardiac pace-maker in hospitalized patients. This procedure can be associated with severe complications. The aim of this article is to provide a practical approach to prevent catheter malposition in states that the guide wire will not pass freely.During central venous insertion in internal jugular vein using modified seldinger technique, when after venous insertion, the passage of the guide wire shows difficulties and don’t pass freely, insertion of an intravenous cannula over the wire and re-insertion of the wire can help to prevent malposition of the wire and the catheter. Use of an intravenous cannula over the guide, in situations that the guide wire cannot pass freely among the needle inserted in internal jugular vein, and re-insertion of the guide can probably prevent or reduce the tissue or vascular trauma and the associated complica-tions. This simple maneuver can be helpful in difficult cases especially in cardiac surgery patients who receive high dose heparin and it is necessary to avoid traumatize-tion of carotid artery.

  19. Hollow dimension of modules

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this paper, we are interested in the following general question: Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki (1≤i≤n) such that M=K1+... +Kn, can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from K1 Kn? We prove the following theorem:Let Mbe an amply supplemented module having finite hollow dimension and let Ki (1≤i≤n) be a finite collection of submodules of Msuch that M=K1+...+Kn. Then the hollow dimension h(M) of Mis the sum of the hollow dimensions of Ki (1≤i≤n) ifand only if Ki is a supplement of K1+...+Ki-1+Ki+1+...+Kn in Mfor each 1≤i≤n.

  20. Use of ultrasound to facilitate femoral nerve block with stimulating catheter

    Institute of Scientific and Technical Information of China (English)

    LI Min; XU Ting; HAN Wen-yong; WANG Xue-dong; JIA Dong-lin; GUO Xiang-yang

    2011-01-01

    Background The adjunction of ultrasound to nerve stimulation has been proven to improve single-injection peripheral nerve block quality. However, few reports have been published determining whether ultrasound can facilitate continuous nerve blocks. In this study, we tested the hypothesis that the addition of ultrasound to nerve stimulation facilitates femoral nerve blocks with a stimulating catheter.Methods In this prospective randomized study, patients receiving continuous femoral nerve blocks for total knee replacement were randomly assigned to either the ultrasound guidance combined with stimulating catheter group (USNS group; n=60) or the stimulating catheter alone group (NS group; n=60). The primary end point was the procedure time (defined as the time from first needle contact with the skin until correct catheter placement). The numbers of needle passes and catheter insertions, onset and quality of femoral nerve blocks, postoperative pain score, and early knee function were also recorded.Results The procedure time was significantly less in the USNS group than in the NS group (9.0 (6.0-22.8) minutes vs.13.5 (6.0-35.9) minutes, P=0.024). The numbers of needle passes and catheter insertions were also significantly less in the USNS group. A greater complete block rate was achieved at 30 minutes in the USNS group (63.3% vs. 38.3%;P=0.010). The postoperative pain score, the number of patients who required bolus local anesthetic and intravenous patient-controlled analgesia, and knee flexion on the second postoperative day were not significantly different between the two groups of patients.Conclusions Ultrasound-assisted placement of a stimulating catheter for femoral nerve blocks decreases the time necessary to perform the block compared with just the nerve-stimulating technique. In addition, a more complete blockade is achieved using the ultrasound-assisted technique.

  1. SILICON NEEDLE ARRAY ON FLEXIBLE SUBSTRATE FOR FLUID TRANSFER

    Institute of Scientific and Technical Information of China (English)

    MA Bin; GAN Zhiyin; LIU Sheng

    2006-01-01

    Transdermal delivery is an attractive alternative, but it is limited by the extremely low permeability of skin. To solve this problem, a novel means-micro needle array based on micro electro-mechanical system (MEMS) technology, is provided to increase permeability of human skin with efficiency, safety and painless delivery. The fabrication method consists of a sequence of deep-reactive ion etching (DRIE), anisotropic wet etching and conformal thin film deposition. The novel technology can enable the realization of micro fabricated micro needle array on a flexible silicon substrate. The micro needle array can be mounted on non-planar surface or even on flexible objects such as a human fingers and arms. The fabricated hollow wall straight micro needles are 200 μm in length, 30 μm inner diameter, and 50 μm outer diameter with 250 μm center-to-center spacing.Flow rate test proves that the polymeric base construction is important to function of micro needles array in package. Glucose solvent tests show that surface tension is the dominant force to affect the characters of flow in micro needles channel.

  2. Hollow spherical supramolecular dendrimers.

    Science.gov (United States)

    Percec, Virgil; Peterca, Mihai; Dulcey, Andrés E; Imam, Mohammad R; Hudson, Steven D; Nummelin, Sami; Adelman, Peter; Heiney, Paul A

    2008-10-01

    The synthesis of a library containing 12 conical dendrons that self-assemble into hollow spherical supramolecular dendrimers is reported. The design principles for this library were accessed by development of a method that allows the identification of hollow spheres, followed by structural and retrostructural analysis of their Pm3n cubic lattice. The first hollow spherical supramolecular dendrimer was made by replacing the tapered dendron, from the previously reported tapered dendritic dipeptide that self-assembled into helical pores, with its constitutional isomeric conical dendron. This strategy generated a conical dendritic dipeptide that self-assembled into a hollow spherical supramolecular dendrimer that self-organizes in a Pm3n cubic lattice. Other examples of hollow spheres were assembled from conical dendrons without a dipeptide at their apex. These are conical dendrons originated from tapered dendrons containing additional benzyl ether groups at their apex. The inner part of the hollow sphere assembled from the dipeptide resembles the path of a spherical helix or loxodrome and, therefore, is chiral. The spheres assembled from other conical dendrons are nonhelical, even when they contain stereocenters on the alkyl groups from their periphery. Functionalization of the apex of the conical dendrons with diethylene glycol allowed the encapsulation of LiOTf and RbOTf in the center of the hollow sphere. These experiments showed that hollow spheres function as supramolecular dendritic capsules and therefore are expected to display functions complementary to those of other related molecular and supramolecular structures. PMID:18771261

  3. Rapid needle-out patient-rollover approach after cone beam CT-guided lung biopsy: effect on pneumothorax rate in 1,191 consecutive patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Im [Seoul National University College of Medicine, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Park, Chang Min; Goo, Jin Mo [Seoul National University College of Medicine, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Seoul National University, Cancer Research Institute, Seoul (Korea, Republic of); Lee, Sang Min [Seoul National University College of Medicine, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of)

    2015-07-15

    To investigate the effect of rapid needle-out patient-rollover approach on the incidence of pneumothorax and drainage catheter placement due to pneumothorax in C-arm Cone-beam CT (CBCT)-guided percutaneous transthoracic needle biopsy (PTNB) of lung lesions. From May 2011 to December 2012, 1227 PTNBs were performed in 1191 patients with a 17-gauge coaxial needle. 617 biopsies were performed without (conventional-group) and 610 with rapid-rollover approach (rapid-rollover-group). Overall pneumothorax rates and incidences of pneumothorax requiring drainage catheter placement were compared between two groups. There were no significant differences in overall pneumothorax rates between conventional and rapid-rollover groups (19.8 % vs. 23.1 %, p = 0.164). However, pneumothorax rate requiring drainage catheter placement was significantly lower in rapid-rollover-group (1.6 %) than conventional-group (4.2 %) (p = 0.010). Multivariate analysis revealed male, age > 60, bulla crossed, fissure crossed, pleura to target distance > 1.3 cm, emphysema along needle tract, and pleural punctures ≥ 2 were significant risk factors of pneumothorax (p < 0.05). Regarding pneumothorax requiring drainage catheter placement, fissure crossed, bulla crossed, and emphysema along needle tract were significant risk factors (p < 0.05), whereas rapid-rollover approach was an independent protective factor (p = 0.002). The rapid needle-out patient-rollover approach significantly reduced the rate of pneumothorax requiring drainage catheter placement after CBCT-guided PTNB. (orig.)

  4. Rapid needle-out patient-rollover approach after cone beam CT-guided lung biopsy: effect on pneumothorax rate in 1,191 consecutive patients

    International Nuclear Information System (INIS)

    To investigate the effect of rapid needle-out patient-rollover approach on the incidence of pneumothorax and drainage catheter placement due to pneumothorax in C-arm Cone-beam CT (CBCT)-guided percutaneous transthoracic needle biopsy (PTNB) of lung lesions. From May 2011 to December 2012, 1227 PTNBs were performed in 1191 patients with a 17-gauge coaxial needle. 617 biopsies were performed without (conventional-group) and 610 with rapid-rollover approach (rapid-rollover-group). Overall pneumothorax rates and incidences of pneumothorax requiring drainage catheter placement were compared between two groups. There were no significant differences in overall pneumothorax rates between conventional and rapid-rollover groups (19.8 % vs. 23.1 %, p = 0.164). However, pneumothorax rate requiring drainage catheter placement was significantly lower in rapid-rollover-group (1.6 %) than conventional-group (4.2 %) (p = 0.010). Multivariate analysis revealed male, age > 60, bulla crossed, fissure crossed, pleura to target distance > 1.3 cm, emphysema along needle tract, and pleural punctures ≥ 2 were significant risk factors of pneumothorax (p < 0.05). Regarding pneumothorax requiring drainage catheter placement, fissure crossed, bulla crossed, and emphysema along needle tract were significant risk factors (p < 0.05), whereas rapid-rollover approach was an independent protective factor (p = 0.002). The rapid needle-out patient-rollover approach significantly reduced the rate of pneumothorax requiring drainage catheter placement after CBCT-guided PTNB. (orig.)

  5. Needle breakage: incidence and prevention.

    Science.gov (United States)

    Malamed, Stanley F; Reed, Kenneth; Poorsattar, Susan

    2010-10-01

    Since the introduction of nonreusable, stainless steel dental local anesthetic needles, needle breakage has become an extremely rare complication of dental local anesthetic injections. But although rare, dental needle breakage can, and does, occur. Review of the literature and personal experience brings into focus several commonalities which, when avoided, can minimize the risk of needle breakage with the fragment being retained from occurring.

  6. Application of enteral nutritional support by needle catheter jejunostomy feeding tube during postoperative adjuvant chemotherapy of staged gastric cancer%延期留置空肠造口管间断肠内营养在进展期胃癌术后辅助化疗中的应用评价

    Institute of Scientific and Technical Information of China (English)

    苏国森; 湛建伟

    2010-01-01

    Objegtive To study the feasibility and clinical effects of enteral nutrition by needle catheter jejunostomy(NCJ)tube in the postoperative adjuvant chemotherapy for patients of staged gastric cancer.Methods Eighty-two patients with staged gastric cancer underwent radical gastrectomy and going to receive chemotherapy were randomly divided into group A(41 cases)and group B(41 cases).All of the patients had been NCJ.Group A received enteral nutrition through the tube during chemotherapy,and group B had been given general diet.A series of parameters were measured post-chemotherapy.And the gastrointestinal complications were carefully observed.Results In post-chemotherapy,the level of hemoglobin,albumin,prealbumin,interleukin-2,natural killer cell activities and CD3+,CDd4+,CD4/CD8 in group A[(106.9±12.0)g/L,(26.2±1.4)g/L,(202.9±32.2)mg/L,(11.9±2.1)μg/L,(21.3±5.2)%,(62.9±3.3)%,(26.1±4.7)%,1.1±0.2]were significantly higher than those in group B(P<0.05 or<0.01).The incidences of vomiting in group A(4.9%,2/41)was significantly lower than that in group B (26.8%,11/41)(P<0.05).The average intake in group A[(1312±114)ml]was significantly more than that in group B[(76.5±186)ml](P<0.05).No severe enteral nutrition related complications occurred in group A.Conclusions It is safe and feasible to enteral nutrition supported by NCJ tube in chemotherapy for patients of staged gastric cancer.It can improve the nutrition status and immune function in the given patients.%目的 研究延期留置空肠造口管间断肠内营养在进展期胃癌术后辅助化疗中应用的可行性及疗效.方法 将进展期胃癌术后行辅助化疗的82例患者按机械抽样法随机分成A、B两组,每组各41例.均于术中放置空肠造口管,A组延期留置空肠造口管至化疗6个疗程结束,每个化疗疗程经空肠造口管给予肠内营养液;B组于化疗前拔除空肠造口管,每个化疗疗程给予普通饮食.比较化疗后两组营养及免疫指

  7. Lumbar epidural catheter placement in the presence of low back tattoos: a review of the safety concerns.

    Science.gov (United States)

    Welliver, Dawn; Welliver, Mark; Carroll, Tammy; James, Peggy

    2010-06-01

    Current fashion in body art includes low back tattoos of varying designs and colors, a trend that presents unique concerns for anesthesia providers. Does the placement of epidural catheters risk the introduction of tattoo pigment dyes into the epidural space through the process of coring? Are there specific risks associated with tattoo dyes and epidural needle placement? We performed a comprehensive review of the literature using multiple search databases with the intent to form guidelines for practice using a level of evidence taxonomy. The available evidence does not identify any specific risks associated with epidural catheter placement through low back tattoos, although tissue coring with tissue transport to deeper sites has been confirmed. Continued investigation is necessary before comprehensive practice guidelines regarding the practice of placing epidural needles and catheters through lumbar tattoos can be developed. We suggest avoidance of piercing tattoos when performing epidural punctures until there is sound evidence of short-term and long-term safety.

  8. Fine needle aspiration of the thyroid

    Science.gov (United States)

    Thyroid nodule fine needle aspirate biopsy; Biopsy - thyroid - skinny-needle; Skinny-needle thyroid biopsy ... cleaned. A thin needle is inserted into the thyroid, and a sample of thyroid cells and fluid ...

  9. Delayed bowel perforation following suprapubic catheter insertion

    OpenAIRE

    Mehta Ajay; Ahmed Shwan J; Rimington Peter

    2004-01-01

    Abstract Background Complications of suprapubic catheter insertion are rare but can be significant. We describe an unusual complication of a delayed bowel perforation following suprapubic catheter insertion. Case presentation A gentleman presented with features of peritonitis and feculent discharge along a suprapubic catheter two months after insertion of the catheter. Conclusion Bowel perforation is the most feared complication of suprapubic catheter insertion especially in patients with low...

  10. Mechanics of needle-tissue interaction

    NARCIS (Netherlands)

    Roesthuis, Roy J.; Veen, van Youri R.J.; Jahya, Alex; Misra, Sarthak

    2011-01-01

    When a needle is inserted into soft tissue, interac- tion forces are developed at the needle tip and along the needle shaft. The needle tip force is due to cutting of the tissue, and the force along the needle shaft is due to friction between needle and tissue. In this study, the friction force is d

  11. Hydrodynamics of catheter biofilm formation

    CERN Document Server

    Sotolongo-Costa, Oscar; Rodriguez-Perez, Daniel; Martinez-Escobar, Sergio; Fernandez-Barbero, Antonio

    2009-01-01

    A hydrodynamic model is proposed to describe one of the most critical problems in intensive medical care units: the formation of biofilms inside central venous catheters. The incorporation of approximate solutions for the flow-limited diffusion equation leads to the conclusion that biofilms grow on the internal catheter wall due to the counter-stream diffusion of blood through a very thin layer close to the wall. This biological deposition is the first necessary step for the subsequent bacteria colonization.

  12. Treatment feasibility study of osteoporosis using minimal invasive laser needle system

    Science.gov (United States)

    Kang, Dongyeon; Ko, Chang-Yong; Ryu, Yeon-Hang; Park, Sunwook; Kim, Han-Sung; Jung, Byungjo

    2010-02-01

    Although the mechanism of laser stimulation effect in bone has not completely understood, laser stimulation is recommended in the treatment of osteoporosis due to positive treatment efficacy. In this study, a minimal invasive laser needle system (MILNS) was developed using a fine hollow needle in order to stimulate directly bone site by guiding an optical fiber. In order to evaluate the MILNS as a treatment method, in-vivo animal experiment study was performed using osteopenic mice. Twelve virginal ICR mice were employed and divided two groups: SHAM-group and LASERgroup. SHARM-group was stimulated by only fine hollow needle and LASER-group by fine hollow needle combined with laser stimulation. All mice were served in-vivo micro-CT images before and after treatment. Three dimensional (3D) structural parameters and vBMD (volume bone mineral density, g/cm3) in the trabecular bone were measured. After 2 weeks of stimulation, the vBMD, BV/TV, Tb.Th and Tb.N in LASER-group were significantly higher than those in SHAM-group (p<0.05). Potentially, this study suggested that the MILNS might prevent the bone loss and maintains the bone mineral density of osteopenic mice.

  13. Implantation of peritoneal catheters by laparotomy: nephrologists obtained similar results to general surgeons

    Directory of Open Access Journals (Sweden)

    Restrepo CA

    2014-10-01

    Full Text Available Cesar A Restrepo, Carlos Alberto Buitrago, Cielo Holguin Division of Nephrology, Department of Health Sciences, Caldas University, Caldas, ColombiaPurpose: To analyze the complications and costs of minilaparotomies performed by a nephrologist (group A compared with conventional laparotomies performed by a surgeon (group B for peritoneal catheter implantation.Setting: Two university hospitals (Santa Sofia and Caldas in Manizales, Caldas, Colombia.Methods: The study included stage 5 chronic kidney disease patients, with indication of renal replacement therapy, who were candidates for peritoneal dialysis and gave informed consent for a peritoneal catheter implant. Minilaparotomies were performed by a nephrologist in a minor surgery room under local anesthesia. Conventional laparotomies were performed by a surgeon in an operating room under general anesthesia.Results: Two nephrologists inserted 157 peritoneal catheters, and seven general surgeons inserted 185 peritoneal catheters. The groups had similar characteristics: the mean age was 55 years, 49.5% were men, and the primary diagnoses were diabetic nephropathy, hypertensive nephropathy, and unknown etiology. The implant was successful for 98.09% of group A and 99.46% of group B. There was no procedure-related mortality. The most frequent complications in the first 30 days postsurgery in group A versus group B, respectively, were: peritonitis (6.37% versus 3.78%, exit-site infection (3.82% versus 2.16%, tunnel infection (0% versus 0.54%, catheter entrapment by omentum (1.27% versus 3.24%, peritoneal effluent spillover (1.91% versus 2.16%, draining failure (4.46% versus 6.49%, hematoma (0% versus 1.08%, catheter migration with kinking (3.18% versus 2.70%, hemoperitoneum (1.27% versus 0%, and hollow viscera accidental puncture (1.91% versus 0.54%. There were no statistically significant differences in the number of complications between groups. In 2013, the cost of a surgeon-implanted peritoneal

  14. Bacteriological Profile of Epidural Catheters

    Directory of Open Access Journals (Sweden)

    B. M. Sahay, Sanjot Dahake, D. K Mendiratta*,Vijayshree Deotale*,B. Premendran, P.S.Dhande, Pratibha Narang*

    2010-01-01

    Full Text Available The bacteriological profile of epidural catheters was studied in 88 patients. Skin swabs before catheterizationand before removal of catheter with their controls were cultured in TSB Medium. The catheter hub, theportion at the skin puncture site and at the tip were cultured in TSB Medium. The 1cm of the catheter bitjust before the tip was cultured in TGB medium for anaerobes.Both, the skin controls swabs and theanaerobic culture, were negative. From the remaining, 56 positive cultures were obtained. Staphylococcusepidermidis was the predominant organism in 52% followed by staphylococcus aureus 25%. The remaining23% was shared by Acinetobacter, Pseudomonas, Klebsiella, and E. coli. All the positive cultures fromskin prior to epidural catheterization had turned sterile by 48 hours, indicating continued bactericidal actionof the disinfectant. The likely source of positive skin cultures at 48 hours is hair follicles.The catheter tipculture was positive in 9 specimen, none of which resulted in the formation of epidural abscess. In 3 casesthe cultures of skin puncture site and the tip were identical indicating tracking-in of the organisms.

  15. Catheter-based photoacoustic endoscope

    Science.gov (United States)

    Yang, Joon-Mo; Li, Chiye; Chen, Ruimin; Zhou, Qifa; Shung, K. Kirk; Wang, Lihong V.

    2014-06-01

    We report a flexible shaft-based mechanical scanning photoacoustic endoscopy (PAE) system that can be potentially used for imaging the human gastrointestinal tract via the instrument channel of a clinical video endoscope. The development of such a catheter endoscope has been an important challenge to realize the technique's benefits in clinical settings. We successfully implemented a prototype PAE system that has a 3.2-mm diameter and 2.5-m long catheter section. As the instrument's flexible shaft and scanning tip are fully encapsulated in a plastic catheter, it easily fits within the 3.7-mm diameter instrument channel of a clinical video endoscope. Here, we demonstrate the intra-instrument channel workability and in vivo animal imaging capability of the PAE system.

  16. Development and application of a microfabricated multimodal neural catheter for neuroscience.

    Science.gov (United States)

    Li, Chunyan; Wu, Zhizhen; Limnuson, Kanokwan; Cheyuo, Cletus; Wang, Ping; Ahn, Chong H; Narayan, Raj K; Hartings, Jed A

    2016-02-01

    We present a microfabricated neural catheter for real-time continuous monitoring of multiple physiological, biochemical and electrophysiological variables that are critical to the diagnosis and treatment of evolving brain injury. The first generation neural catheter was realized by polyimide-based micromachining and a spiral rolling packaging method. The mechanical design and electrical operation of the microsensors were optimized and tailored for multimodal monitoring in rat brain such that the potential thermal, chemical and electrical crosstalk among the microsensors as well as errors from micro-environmental fluctuations are minimized. In vitro cytotoxicity analyses suggest that the developed neural catheters are minimally toxic to rat cortical neuronal cultures. In addition, in vivo histopathology results showed neither acute nor chronic inflammation for 7 days post implantation. The performance of the neural catheter was assessed in an in vivo needle prick model as a translational replica of a "mini" traumatic brain injury. It successfully monitored the expected transient brain oxygen, temperature, regional cerebral blood flow, and DC potential changes during the passage of spreading depolarization waves. We envisage that the developed multimodal neural catheter can be used to decipher the causes and consequences of secondary brain injury processes with high spatial and temporal resolution while reducing the potential for iatrogenic injury inherent to current use of multiple invasive probes. PMID:26780443

  17. Fabrication of Microbeads with a Controllable Hollow Interior and Porous Wall Using a Capillary Fluidic Device

    OpenAIRE

    Choi, Sung-Wook; Zhang, Yu; Xia, Younan

    2009-01-01

    Poly(d,l-lactide-co-glycolide) (PLGA) microbeads with a hollow interior and porous wall are prepared using a simple fluidic device fabricated with PVC tubes, glass capillaries, and a needle. Using the fluidic device with three flow channels, uniform water-in-oil-in-water (W-O-W) emulsions with a single inner water droplet can be achieved with controllable dimensions by varying the flow rate of each phase. The resultant W-O-W emulsions evolve into PLGA microbeads with a hollow interior and por...

  18. 21 CFR 882.4100 - Ventricular catheter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular catheter. 882.4100 Section 882.4100...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4100 Ventricular catheter. (a) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for...

  19. have a hollow leg

    Institute of Scientific and Technical Information of China (English)

    周立

    2003-01-01

    英语对话 A:We must prevent our family members from getting involved with drugs, really. B:That’s a sure thing.We must make sure that they never involve them- selves with that. A:By the way,does your husband drink a lot? B:Yeah.That’s the only thing that keeps worrying me.And he often boasts that he has a hollow leg and nobody can drink him under the ta- ble.

  20. Emergency percutaneous needle decompression for tension pneumoperitoneum

    Directory of Open Access Journals (Sweden)

    Körner Markus

    2011-05-01

    Full Text Available Abstract Background Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic. Methods This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension. Results Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs, between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs. Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion, bridging the time to the start of the operation. Conclusions Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no

  1. Effectiveness of different central venous catheters for catheter-related infections: a network meta-analysis.

    Science.gov (United States)

    Wang, H; Huang, T; Jing, J; Jin, J; Wang, P; Yang, M; Cui, W; Zheng, Y; Shen, H

    2010-09-01

    We aimed to compare the effectiveness of various catheters for prevention of catheter-related infection and to evaluate whether specific catheters are superior to others for reducing catheter-related infections. We identified randomised, controlled trials that compared different types of central venous catheter (CVC), evaluating catheter-related infections in a systematic search of articles published from January 1996 to November 2009 via Medline, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials. Network meta-analysis with a mixed treatment comparison method using Bayesian Markov Chain Monte Carlo simulation was used to combine direct within-trial, between-treatment comparisons with indirect trial evidence. Forty-eight clinical trials (12 828 CVCs) investigating 10 intervention catheters contributed to the analyses. For prevention of CVC colonisation, adjusted silver iontophoretic catheters (odds ratio: 0.58; 95% confidence interval: 0.33-0.95), chlorhexidine and silver sulfadiazine catheters (0.49; 0.36-0.64), chlorhexidine and silver sulfadiazine blue plus catheters (0.37; 0.17-0.69), minocycline-rifampicin catheters (0.28; 0.17-0.43) and miconazole-rifampicin catheters (0.11; 0.02-0.33) were associated with a significantly lower rate of catheter colonisation compared with standard catheters. For prevention of CRBSI, adjusted heparin-bonded catheters (0.20; 0.06-0.44) and minocycline-rifampicin catheters (0.18; 0.08-0.34) were associated with a significantly lower rate of CRBSI with standard catheters. Rifampicin-based impregnated catheters seem to be better for prevention of catheter-related infection compared with the other catheters.

  2. Cytometric Catheter for Neurosurgical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Evans III, Boyd Mccutchen [ORNL; Allison, Stephen W [ORNL; Fillmore, Helen [ORNL; Broaddus, William C [ORNL; Dyer, Rachel L [ORNL; Gillies, George [ORNL

    2010-01-01

    Implantation of neural progenitor cells into the central nervous system has attracted strong interest for treatment of a variety of pathologies. For example, the replacement of dopamine-producing (DA) neural cells in the brain appears promising for the treatment of patients affected by Parkinson's disease. Previous studies of cell-replacement strategies have shown that less than 90% of implanted cells survive longer than 24 - 48 hours following the implantation procedure. However, it is unknown if these cells were viable upon delivery, or if they were affected by other factors such as brain pathology or an immune response. An instrumented cell-delivery catheter has been developed to assist in answering these questions by facilitating quantification and monitoring of the viability of the cells delivered. The catheter uses a fiber optic probe to perform flourescence-based cytometric measurments on cells exiting the port at the catheter tip. The current implementation of this design is on a 3.2 mm diameter catheter with 245 micrometer diameter optical fibers. Results of fluorescence testing data are presented and show that the device can characterize the quantity of cell densities ranging from 60,000 cells/ml to 600,000 cells/ml with a coefficient of determination of 0.93.

  3. Transhepatic venous catheters for hemodialysis

    Directory of Open Access Journals (Sweden)

    Mohamed El Gharib

    2014-06-01

    Conclusion: Based on our findings, transhepatic hemodialysis catheters have proven to achieve good long-term functionality. A high level of maintenance is required to preserve patency, although this approach provides remarkably durable access for patients who have otherwise exhausted access options.

  4. EM-navigated catheter placement for gynecologic brachytherapy: an accuracy study

    Science.gov (United States)

    Mehrtash, Alireza; Damato, Antonio; Pernelle, Guillaume; Barber, Lauren; Farhat, Nabgha; Viswanathan, Akila; Cormack, Robert; Kapur, Tina

    2014-03-01

    Gynecologic malignancies, including cervical, endometrial, ovarian, vaginal and vulvar cancers, cause significant mortality in women worldwide. The standard care for many primary and recurrent gynecologic cancers consists of chemoradiation followed by brachytherapy. In high dose rate (HDR) brachytherapy, intracavitary applicators and /or interstitial needles are placed directly inside the cancerous tissue so as to provide catheters to deliver high doses of radiation. Although technology for the navigation of catheters and needles is well developed for procedures such as prostate biopsy, brain biopsy, and cardiac ablation, it is notably lacking for gynecologic HDR brachytherapy. Using a benchtop study that closely mimics the clinical interstitial gynecologic brachytherapy procedure, we developed a method for evaluating the accuracy of image-guided catheter placement. Future bedside translation of this technology offers the potential benefit of maximizing tumor coverage during catheter placement while avoiding damage to the adjacent organs, for example bladder, rectum and bowel. In the study, two independent experiments were performed on a phantom model to evaluate the targeting accuracy of an electromagnetic (EM) tracking system. The procedure was carried out using a laptop computer (2.1GHz Intel Core i7 computer, 8GB RAM, Windows 7 64-bit), an EM Aurora tracking system with a 1.3mm diameter 6 DOF sensor, and 6F (2 mm) brachytherapy catheters inserted through a Syed-Neblett applicator. The 3D Slicer and PLUS open source software were used to develop the system. The mean of the targeting error was less than 2.9mm, which is comparable to the targeting errors in commercial clinical navigation systems.

  5. Delayed bowel perforation following suprapubic catheter insertion

    Directory of Open Access Journals (Sweden)

    Mehta Ajay

    2004-12-01

    Full Text Available Abstract Background Complications of suprapubic catheter insertion are rare but can be significant. We describe an unusual complication of a delayed bowel perforation following suprapubic catheter insertion. Case presentation A gentleman presented with features of peritonitis and feculent discharge along a suprapubic catheter two months after insertion of the catheter. Conclusion Bowel perforation is the most feared complication of suprapubic catheter insertion especially in patients with lower abdominal scar. The risk may be reduced with the use of ultrasound scan guidance.

  6. Smart needles for percutaneous interventions

    NARCIS (Netherlands)

    Henken, K.R.

    2014-01-01

    The development of advanced needles for diagnostic and therapeutic purposes such as ablation and brachytherapy in the liver has offered minimally invasive therapies to patients that were previously untreatable. This thesis focuses on accurate placement of such needles guided by magnetic resonance im

  7. Fast, automatic, and accurate catheter reconstruction in HDR brachytherapy using an electromagnetic 3D tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Eric; Racine, Emmanuel; Beaulieu, Luc, E-mail: Luc.Beaulieu@phy.ulaval.ca [Département de physique, de génie physique et d’optique et Centre de recherche sur le cancer de l’Université Laval, Université Laval, Québec, Québec G1V 0A6, Canada and Département de radio-oncologie et Axe Oncologie du Centre de recherche du CHU de Québec, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Binnekamp, Dirk [Integrated Clinical Solutions and Marketing, Philips Healthcare, Veenpluis 4-6, Best 5680 DA (Netherlands)

    2015-03-15

    Purpose: In high dose rate brachytherapy (HDR-B), current catheter reconstruction protocols are relatively slow and error prone. The purpose of this technical note is to evaluate the accuracy and the robustness of an electromagnetic (EM) tracking system for automated and real-time catheter reconstruction. Methods: For this preclinical study, a total of ten catheters were inserted in gelatin phantoms with different trajectories. Catheters were reconstructed using a 18G biopsy needle, used as an EM stylet and equipped with a miniaturized sensor, and the second generation Aurora{sup ®} Planar Field Generator from Northern Digital Inc. The Aurora EM system provides position and orientation value with precisions of 0.7 mm and 0.2°, respectively. Phantoms were also scanned using a μCT (GE Healthcare) and Philips Big Bore clinical computed tomography (CT) system with a spatial resolution of 89 μm and 2 mm, respectively. Reconstructions using the EM stylet were compared to μCT and CT. To assess the robustness of the EM reconstruction, five catheters were reconstructed twice and compared. Results: Reconstruction time for one catheter was 10 s, leading to a total reconstruction time inferior to 3 min for a typical 17-catheter implant. When compared to the μCT, the mean EM tip identification error was 0.69 ± 0.29 mm while the CT error was 1.08 ± 0.67 mm. The mean 3D distance error was found to be 0.66 ± 0.33 mm and 1.08 ± 0.72 mm for the EM and CT, respectively. EM 3D catheter trajectories were found to be more accurate. A maximum difference of less than 0.6 mm was found between successive EM reconstructions. Conclusions: The EM reconstruction was found to be more accurate and precise than the conventional methods used for catheter reconstruction in HDR-B. This approach can be applied to any type of catheters and applicators.

  8. Birefringent hollow core fibers

    DEFF Research Database (Denmark)

    Roberts, John

    2007-01-01

    Hollow core photonic crystal fiber (HC-PCF), fabricated according to a nominally non-birefringent design, shows a degree of un-controlled birefringence or polarization mode dispersion far in excess of conventional non polarization maintaining fibers. This can degrade the output pulse in many...... and an increased overlap between the polarization modes at the glass interfaces. The interplay between these effects leads to a wavelength for optimum polarization maintenance, lambda(PM), which is detuned from the wavelength of highest birefringence. By a suitable fiber design involving antiresonance of the core...

  9. Transhepatic venous catheters for hemodialysis

    OpenAIRE

    Mohamed El Gharib; Gamal Niazi; Waleed Hetta; Yahya Makkeyah

    2014-01-01

    Purpose: To describe our experience with the technique of transhepatic venous access for hemodialysis and to evaluate its functionality and complications. Patients and methods: From March 2012 till October 2012, 23 patients with age ranging from 12 to 71 years old having end-stage renal disease (ESRD) were included in our study and were subjected to transhepatic venous catheter insertion. In 21 patients there were not any remaining patent peripheral venous accesses. In 2 patients there wer...

  10. Real-Time 3-Dimensional Ultrasound-Assisted Infraclavicular Brachial Plexus Catheter Placement: Implications of a New Technology

    Directory of Open Access Journals (Sweden)

    Steven R. Clendenen

    2010-01-01

    Full Text Available Background. There are a variety of techniques for targeting placement of an infraclavicular blockade; these include eliciting paresthesias, nerve stimulation, and 2-dimensional (2D ultrasound (US guidance. Current 2D US allows direct visualization of a “flat” image of the advancing needle and neurovascular structures but without the ability to extensively analyze multidimensional data and allow for real-time manipulation. Three-dimensional (3D ultrasonography has gained popularity and usefulness in many clinical specialties such as obstetrics and cardiology. We describe some of the potential clinical applications of 3D US in regional anesthesia. Methods. This case represents an infraclavicular catheter placement facilitated by 3D US, which demonstrates 360-degree spatial relationships of the entire anatomic region. Results. The block needle, peripheral nerve catheter, and local anesthetic diffusion were observed in multiple planes of view without manipulation of the US probe. Conclusion. Advantages of 3D US may include the ability to confirm correct needle and catheter placement prior to the injection of local anesthetic. The spread of local anesthetic along the length of the nerve can be easily observed while manipulating the 3D images in real-time by simply rotating the trackball on the US machine to provide additional information that cannot be identified with 2D US alone.

  11. Infections associated with the central venous catheters.

    Science.gov (United States)

    Drasković, Biljana; Fabri, Izabella; Benka, Anna Uram; Rakić, Goran

    2014-01-01

    Central venous catheters are of an essential importance to critically ill patients who require long-term venous access for various purposes. Their use made the treatment much easier, but still they are not harmless and are prone to numerous complications. Catheter infections represent the most significant complication in their use. The frequency of infections varies in different patient care settings, but their appearance mostly depends on the patient's health condition, catheter insertion time, localization of the catheter and type of the used catheter. Since they are one of the leading causes of nosocomial infections and related to significant number of morbidity and mortality in intensive care units, it is very important that maximal aseptic precautions are taken during the insertion and the maintenance period. Prevention of infection of the central venous catheters demands several measures that should be applied routinely.

  12. NRGTM RF powered transseptal needle: a useful technique for transcatheter atrial septostomy and Fontan fenestration: report of three cases

    Directory of Open Access Journals (Sweden)

    Tevfik Karagöz

    2014-10-01

    Full Text Available Transseptal puncture (TSP is a frequently performed procedure for gaining access to the left atrium for catheter ablation, hemodynamic assessment of the left heart, left ventricular assist device implantation, percutaneous left atrial appendage closure or mitral valvuloplasty during childhood and adulthood. The standard technique for transseptal puncture applies mechanical pressure on the fossa ovalis with a Brockenbrough needle. However, this method is not feasible when the fossa ovalis is thick and aneurysmatic. In such patients, the radiofrequency ablation energy systems can be offered as a better alternative for TSP. Here, we aimed to demonstrate the outcome of transseptal puncture performed with an NRGTM RF powered transseptal needle in three patients.

  13. Flush Foley's catheter: The most easy way

    OpenAIRE

    Vijay P. Agrawal

    2013-01-01

    Introduction: Foley catheters are used for monitoring urine output in anesthetized patients, comatose patients, incontinent patients, acute urinary retention, paralysed patients, trauma patients, urethral surgeries, ureterectomy, kidney disease, before and after cesarean sections etc. When a Foley catheter becomes clogged, it can cause various complications. For which it is flushed or replaced.Objectives: To find a simple way to flush a Foleys catheter.Material & Methods: Patient was expl...

  14. A case of misplaced permacath dialysis catheter

    Directory of Open Access Journals (Sweden)

    Mohammed Arshad Ali

    2015-01-01

    Full Text Available Central venous placement using ultrasound has significantly reduced the complications associated with blind puncture. The central venous catheter can still get misplaced if it follows an anomalous route after appropriate puncture of desired vessel. We report a case of misplaced dialysis catheter into the accessory hemiazygos vein which resulted in a large hemothorax, and we recommend the routine use of a fluoroscope for placement of dialysis catheters so as to avoid serious complications.

  15. Computed tomography-guided percutaneous catheter drainage of primary and secondary iliopsoas abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Cantasdemir, M. E-mail: cantas1@yahoo.com; Kara, B.; Cebi, D.; Selcuk, N.D.; Numan, F

    2003-10-01

    AIM: To report our experience with computed tomography (CT)-guided percutaneous catheter drainage (PCD) of iliopsoas abscesses. MATERIALS AND METHODS: Twenty-two iliopsoas abscesses in 21 patients (11 women, 10 men) aged between 18 and 66 years (mean 36 years) were treated with PCD. Abdominal CT demonstrated the iliopsoas abscesses, which were definitively determined by Gram staining and aspirate cultures. Twenty of the 22 iliopsoas abscesses were primary and two were secondary. All PCD procedures were performed under local anaesthesia using a single-step trocar technique (n=19) or Seldinger technique (n=3). RESULTS: PCD was an effective treatment in 21 out of the 22 iliopsoas abscesses. Recurrence was seen in three abscesses as minimal residual collections. Two of them resolved spontaneously with anti-tuberculous regimen. One required percutaneous needle aspiration. The procedure failed in a diabetic patient with a secondary abscess, who died due to sepsis. The length of time that catheters remained in place ranged from 21 to 75 days (mean 59.7 days). Complications included catheter dislocation in four abscesses, which required removal of dislocated catheters and indwelling new ones. CONCLUSION: CT-guided PCD is a safe and effective front-line treatment of iliopsoas abscesses. Surgery should be reserved for failure of PCD and presence of contraindications to PCD.

  16. Impact of different catheter lock strategies on bacterial colonization of permanent central venous hemodialysis catheters.

    Science.gov (United States)

    Erb, Stefan; Widmer, Andreas F; Tschudin-Sutter, Sarah; Neff, Ursula; Fischer, Manuela; Dickenmann, Michael; Grosse, Philipp

    2013-12-01

    Thirty-nine hemodialysis patients with permanent central venous catheters were analyzed for bacterial catheter colonization comparing different catheter-lock strategies. The closed needleless Tego connector with sodium chloride lock solution was significantly more frequently colonized with bacteria than the standard catheter caps with antimicrobially active citrate lock solution (odds ratio, 0.22 [95% confidence interval, 0.07-0.71]; P = .011).

  17. Mechanical performance of disposable surgical needle holders.

    Science.gov (United States)

    Francis, E H; Towler, M A; Moody, F P; McGregor, W; Himel, H N; Rodeheaver, G T; Edlich, R F

    1992-01-01

    The mechanical performance of disposable Webster surgical needle holders supplied by three different surgical instrument companies was determined by recording the forces (clamping moment) applied by the different needle holder jaws to curved surgical needles. This investigation demonstrated that there was a large variability in the mechanical performance of the disposable needle holders supplied by each surgical instrument company. In addition, the mechanical performance of the disposable needle holder of each surgical instrument company was distinctly different.

  18. The common structural architecture of Shigella flexneri and Salmonella typhimurium type three secretion needles.

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Demers

    2013-03-01

    Full Text Available The Type Three Secretion System (T3SS, or injectisome, is a macromolecular infection machinery present in many pathogenic Gram-negative bacteria. It consists of a basal body, anchored in both bacterial membranes, and a hollow needle through which effector proteins are delivered into the target host cell. Two different architectures of the T3SS needle have been previously proposed. First, an atomic model of the Salmonella typhimurium needle was generated from solid-state NMR data. The needle subunit protein, PrgI, comprises a rigid-extended N-terminal segment and a helix-loop-helix motif with the N-terminus located on the outside face of the needle. Second, a model of the Shigella flexneri needle was generated from a high-resolution 7.7-Å cryo-electron microscopy density map. The subunit protein, MxiH, contains an N-terminal α-helix, a loop, another α-helix, a 14-residue-long β-hairpin (Q51-Q64 and a C-terminal α-helix, with the N-terminus facing inward to the lumen of the needle. In the current study, we carried out solid-state NMR measurements of wild-type Shigella flexneri needles polymerized in vitro and identified the following secondary structure elements for MxiH: a rigid-extended N-terminal segment (S2-T11, an α-helix (L12-A38, a loop (E39-P44 and a C-terminal α-helix (Q45-R83. Using immunogold labeling in vitro and in vivo on functional needles, we located the N-terminus of MxiH subunits on the exterior of the assembly, consistent with evolutionary sequence conservation patterns and mutagenesis data. We generated a homology model of Shigella flexneri needles compatible with both experimental data: the MxiH solid-state NMR chemical shifts and the state-of-the-art cryoEM density map. These results corroborate the solid-state NMR structure previously solved for Salmonella typhimurium PrgI needles and establish that Shigella flexneri and Salmonella typhimurium subunit proteins adopt a conserved structure and orientation in their

  19. Attitudes Towards Catheter Ablation for Atrial Fibrillation

    DEFF Research Database (Denmark)

    Vadmann, Henrik; Pedersen, Susanne S; Nielsen, Jens Cosedis;

    2015-01-01

    BACKGROUND: Catheter ablation for atrial fibrillation (AF) is an important but expensive procedure that is the subject of some debate. Physicians´ attitudes towards catheter ablation may influence promotion and patient acceptance. This is the first study to examine the attitudes of Danish...

  20. Alternatives to Indwelling Catheters Cause Unintended Complications.

    Science.gov (United States)

    Nguyen, Jessica; Harvey, Ellen M; Lollar, Daniel I; Bradburn, Eric H; Hamill, Mark E; Collier, Bryan R; Love, Katie M

    2016-08-01

    To reduce the risk of catheter-associated urinary tract infection (CAUTI), limiting use of indwelling catheters is encouraged with alternative collection methods and early removal. Adverse effects associated with such practices have not been described. We also determined if CAUTI preventative measures increase the risk of catheter-related complications. We hypothesized that there are complications associated with early removal of indwelling catheters. We described complications associated with indwelling catheterization and intermittent catheterization, and compared complication rates before and after policy updates changed catheterization practices. We performed retrospective cohort analysis of trauma patients admitted between August 1, 2009, and December 31, 2013 who required indwelling catheter. Associations between catheter days and adverse outcomes such as infection, bladder overdistention injury, recatheterization, urinary retention, and patients discharged with indwelling catheter were evaluated. The incidence of CAUTI and the total number of catheter days pre and post policy change were similar. The incidence rate of urinary retention and associated complications has increased since the policy changed. Practices intended to reduce the CAUTI rate are associated with unintended complications, such as urinary retention. Patient safety and quality improvement programs should monitor all complications associated with urinary catheterization practices, not just those that represent financial penalties. PMID:27657581

  1. Catheter ablation of parahisian premature ventricular complex.

    Science.gov (United States)

    Kim, Jun; Kim, Jeong Su; Park, Yong Hyun; Kim, June Hong; Chun, Kook Jin

    2011-12-01

    Catheter ablation is performed in selected patients with a symptomatic premature ventricular complex (PVC) or PVC-induced cardiomyopathy. Ablation of PVC from the His region has a high risk of inducing a complete atrioventricular block. Here we report successful catheter ablation of a parahisian PVC in a 63-year-old man.

  2. Soft thrombus formation in radiofrequency catheter ablation

    NARCIS (Netherlands)

    Demolin, JM; Eick, OJ; Munch, K; Koullick, E; Nakagawa, H; Wittkampf, FHM

    2002-01-01

    During RF catheter ablation, local temperature elevation can result in coagulum formation on the ablation electrode, resulting in impedance rise. A recent study has also demonstrated the formation of a so-called soft thrombus during experimental ablations. This deposit poorly adhered to the catheter

  3. Automated Pointing of Cardiac Imaging Catheters.

    Science.gov (United States)

    Loschak, Paul M; Brattain, Laura J; Howe, Robert D

    2013-12-31

    Intracardiac echocardiography (ICE) catheters enable high-quality ultrasound imaging within the heart, but their use in guiding procedures is limited due to the difficulty of manually pointing them at structures of interest. This paper presents the design and testing of a catheter steering model for robotic control of commercial ICE catheters. The four actuated degrees of freedom (4-DOF) are two catheter handle knobs to produce bi-directional bending in combination with rotation and translation of the handle. An extra degree of freedom in the system allows the imaging plane (dependent on orientation) to be directed at an object of interest. A closed form solution for forward and inverse kinematics enables control of the catheter tip position and the imaging plane orientation. The proposed algorithms were validated with a robotic test bed using electromagnetic sensor tracking of the catheter tip. The ability to automatically acquire imaging targets in the heart may improve the efficiency and effectiveness of intracardiac catheter interventions by allowing visualization of soft tissue structures that are not visible using standard fluoroscopic guidance. Although the system has been developed and tested for manipulating ICE catheters, the methods described here are applicable to any long thin tendon-driven tool (with single or bi-directional bending) requiring accurate tip position and orientation control.

  4. Needle-Stick Injury and Medical Students' Knowledge

    Directory of Open Access Journals (Sweden)

    Shahin Gasemi

    2012-09-01

    Full Text Available Health-care worker's contamination was noticed with discovery of blood-borne pathogens in the late 1980's. The main way of this transmission is via hollow intravascular needles, although other sharp instruments are also important [1]. Sixty blood-borne pathogens have been reported until now which contain 26 kinds of viruses, 18 kinds of bacteria/ rickettsias, 13 kinds of parasites and 3 different fungi. However, Hepatitis B, C and HIV viruses responsible for the majority of occupational transmission [2]. The risk of this transmission in Hepatitis B (30%, Hepatitis C (1.8% and HIV (0.3% depend on patient's viral load and the amount of blood that has been transmitted from patient to health-care worker [3].

  5. Unusual migration of pulmonary artery catheter

    Directory of Open Access Journals (Sweden)

    Sanjay Kuravinakop

    2007-01-01

    Full Text Available Pulmonary artery catheter is widely used in intensive care. Distal migration of the catheter is a know complication. Diagnosis of such a migration is made by both clinical criteria and radiographs. A 55 year old septic lady was admitted to the intensive care unit. Pulmonary artery catheter introduced for cardiac output monitoring migrated from right lung to left lung. Diagnosis was made following a chest radiograph the following day of insertion with the clinical criteria remaining unaltered. Migration of pulmonary artery catheter can occur not only distally but from one lung to another. Clinical criteria alone cannot rule out migration. Chest radiographs form an important part in monitoring the position of the pulmonary artery catheter.

  6. MRI-guided prostate focal laser ablation therapy using a mechatronic needle guidance system

    Science.gov (United States)

    Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Davidson, Sean R. H.; Trachtenberg, John; Fenster, Aaron

    2014-03-01

    Focal therapy of localized prostate cancer is receiving increased attention due to its potential for providing effective cancer control in select patients with minimal treatment-related side effects. Magnetic resonance imaging (MRI)-guided focal laser ablation (FLA) therapy is an attractive modality for such an approach. In FLA therapy, accurate placement of laser fibers is critical to ensuring that the full target volume is ablated. In practice, error in needle placement is invariably present due to pre- to intra-procedure image registration error, needle deflection, prostate motion, and variability in interventionalist skill. In addition, some of these sources of error are difficult to control, since the available workspace and patient positions are restricted within a clinical MRI bore. In an attempt to take full advantage of the utility of intraprocedure MRI, while minimizing error in needle placement, we developed an MRI-compatible mechatronic system for guiding needles to the prostate for FLA therapy. The system has been used to place interstitial catheters for MRI-guided FLA therapy in eight subjects in an ongoing Phase I/II clinical trial. Data from these cases has provided quantification of the level of uncertainty in needle placement error. To relate needle placement error to clinical outcome, we developed a model for predicting the probability of achieving complete focal target ablation for a family of parameterized treatment plans. Results from this work have enabled the specification of evidence-based selection criteria for the maximum target size that can be confidently ablated using this technique, and quantify the benefit that may be gained with improvements in needle placement accuracy.

  7. Central venous catheters: detection of catheter complications and therapeutical options; Zentralvenoese Katheter: Diagnostik von Komplikationen und therapeutische Optionen

    Energy Technology Data Exchange (ETDEWEB)

    Gebauer, B.; Beck, A. [Universitaetsmedizin Charite, Berlin (Germany). Klinik fuer Strahlenheilkunde; Wagner, H.J. [Vivantes-Kliniken, Friedrichshain und Am Urban, Berlin (Germany). Radiologie; Vivantes-Kliniken, Hellersdorf und Prenzlauer Berg (Germany). Radiologie

    2008-06-15

    For modern medicine central venous catheters play an important role for diagnostic and therapeutic options. Catheter implantation, complication detection and therapy of catheter complications are an increasing demand for the radiologist. The review article provides an overview of different catheter types, their indications, advantages and disadvantages. Catheter malpositions are usually detectable in conventional X-ray. Most malpositions are correctable using interventional-radiological techniques. In addition therapeutical options for thrombotic complications (venous thrombosis, catheter occlusion, fibrin sheath) are discussed. In case of an infectious catheter complication, usually a catheter extraction and re-implantation is necessary.

  8. Dry needling: a literature review with implications for clinical practice guidelines1

    Science.gov (United States)

    Dunning, James; Butts, Raymond; Mourad, Firas; Young, Ian; Flannagan, Sean; Perreault, Thomas

    2014-01-01

    Background: Wet needling uses hollow-bore needles to deliver corticosteroids, anesthetics, sclerosants, botulinum toxins, or other agents. In contrast, dry needling requires the insertion of thin monofilament needles, as used in the practice of acupuncture, without the use of injectate into muscles, ligaments, tendons, subcutaneous fascia, and scar tissue. Dry needles may also be inserted in the vicinity of peripheral nerves and/or neurovascular bundles in order to manage a variety of neuromusculoskeletal pain syndromes. Nevertheless, some position statements by several US State Boards of Physical Therapy have narrowly defined dry needling as an ‘intramuscular’ procedure involving the isolated treatment of ‘myofascial trigger points’ (MTrPs). Objectives: To operationalize an appropriate definition for dry needling based on the existing literature and to further investigate the optimal frequency, duration, and intensity of dry needling for both spinal and extremity neuromusculoskeletal conditions. Major findings: According to recent findings in the literature, the needle tip touches, taps, or pricks tiny nerve endings or neural tissue (i.e. ‘sensitive loci’ or ‘nociceptors’) when it is inserted into a MTrP. To date, there is a paucity of high-quality evidence to underpin the use of direct dry needling into MTrPs for the purpose of short and long-term pain and disability reduction in patients with musculoskeletal pain syndromes. Furthermore, there is a lack of robust evidence validating the clinical diagnostic criteria for trigger point identification or diagnosis. High-quality studies have also demonstrated that manual examination for the identification and localization of a trigger point is neither valid nor reliable between-examiners. Conclusions: Several studies have demonstrated immediate or short-term improvements in pain and/or disability by targeting trigger points (TrPs) using in-and-out techniques such as ‘pistoning’ or

  9. Needle biopsy of the breast.

    Science.gov (United States)

    Millis, R R

    1984-01-01

    Recently, there has been a considerable increase in the use of both fine-needle aspiration biopsy (aspiration cytology) and tissue-core needle biopsy of the breast. In patients with suspected breast cancer, needle biopsy is frequently used to confirm the diagnosis before treatment is planned. This allows a more thoughtful approach to the patient and full screening for possible metastatic disease prior to definitive surgery. Needle biopsy techniques are simple, rapid, can be performed in the doctor's office, and save time, equipment, and hospital beds. Complications are few. Aspiration cytology has the advantage that it is quick to perform, the preparation can be examined almost immediately and, in the event of an unsatisfactory smear, the procedure can be repeated. However, the diagnosis is based on purely cytological evaluation, and the information obtained is somewhat limited. Reported accuracy rates range from 42 to 96%. False positive reports are rare but have occurred in most centers, and a high degree of accuracy will only be obtained by experienced practitioners. Tissue-core needle biopsy has the advantage that the diagnosis is based on histopathological assessment, but the procedure is slightly more time consuming, is more traumatic for the patient, and the equipment is more expensive. Accuracy rates range from 67 to 98.5%. During the past 4 years, 329 tissue-core (Tru-Cut) biopsies have been performed in the Guy's Hospital Breast Unit, with an accuracy rate of 83% in the diagnosis of carcinoma. The procedure has been acceptable to most patients, and complications have been minimal. Studies comparing the use of aspiration cytology and tissue-core needle biopsy in the diagnosis of mammary carcinoma have produced variable results. Both methods have advantages and disadvantages, and the choice of technique must depend on the clinical situation and the preferences and skills of the practitioners involved in the management of the patient. PMID:6377049

  10. Switching a Nanocluster Core from Hollow to Non-hollow

    KAUST Repository

    Bootharaju, Megalamane Siddaramappa

    2016-03-24

    Modulating the structure-property relationship in atomically precise nanoclusters (NCs) is vital for developing novel NC materials and advancing their applications. While promising biphasic ligand-exchange (LE) strategies have been developed primarily to attain novel NCs, understanding the mechanistic aspects involved in tuning the core and the ligand-shell of NCs in such biphasic processes is challenging. Here, we design a single phase LE process that enabled us to elucidate the mechanism of how a hollow NC (e.g., [Ag44(SR)30]4-, -SR: thiolate) converts into a non-hollow NC (e.g., [Ag25(SR)18]-), and vice versa. Our study reveals that the complete LE of the hollow [Ag44(SPhF)30]4- NCs (–SPhF: 4-fluorobenzenethiolate) with incoming 2,4-dimethylbenzenethiol (HSPhMe2) induced distortions in the Ag44 structure forming the non-hollow [Ag25(SPhMe2)18]- by a disproportionation mechanism. While the reverse reaction of [Ag25(SPhMe2)18]- with HSPhF prompted an unusual dimerization of Ag25, followed by a rearrangement step that reproduces the original [Ag44(SPhF)30]4-. Remarkably, both the forward and the backward reactions proceed through similar size intermediates that seem to be governed by the boundary conditions set by the thermodynamic and electronic stability of the hollow and non-hollow metal cores. Furthermore, the resizing of NCs highlights the surprisingly long-range effect of the ligands which are felt by atoms far deep in the metal core, thus opening a new path for controlling the structural evolution of nanoparticles.

  11. Autosizing Control Panel for Needle Bearing

    OpenAIRE

    Prof.A.R.Wadhekar,; Ms Jyoti R. Rajput

    2016-01-01

    A needle roller bearing is a bearing which uses small cylindrical rollers. Bearings are used to reduce friction of any rotating surface. Needle bearings have a large surface in contact with the bearing outer surfaces as compared to ball bearings. There is less added clearance(Diameter of the shaft and the diameter of the bearing are different) so they are much compact. The structure consists of a needle cage which contains the needle rollersthemselves and an outer race (The housin...

  12. Dry needling — peripheral and central considerations

    OpenAIRE

    Dommerholt, Jan

    2011-01-01

    Dry needling is a common treatment technique in orthopedic manual physical therapy. Although various dry needling approaches exist, the more common and best supported approach targets myofascial trigger points. This article aims to place trigger point dry needling within the context of pain sciences. From a pain science perspective, trigger points are constant sources of peripheral nociceptive input leading to peripheral and central sensitization. Dry needling cannot only reverse some aspects...

  13. Cryoballoon Catheter Ablation in Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Cevher Ozcan

    2011-01-01

    Full Text Available Pulmonary vein isolation with catheter ablation is an effective treatment in patients with symptomatic atrial fibrillation refractory or intolerant to antiarrhythmic medications. The cryoballoon catheter was recently approved for this procedure. In this paper, the basics of cryothermal energy ablation are reviewed including its ability of creating homogenous lesion formation, minimal destruction to surrounding vasculature, preserved tissue integrity, and lower risk of thrombus formation. Also summarized here are the publications describing the clinical experience with the cryoballoon catheter ablation in both paroxysmal and persistent atrial fibrillation, its safety and efficacy, and discussions on the technical aspect of the cryoballoon ablation procedure.

  14. Catheter-directed Thrombolysis in Acute Superior Vena Cava Syndrome Caused by Central Venous Catheters.

    Science.gov (United States)

    Cui, Jie; Kawai, Tasuo; Irani, Zubin

    2015-01-01

    Indwelling central venous catheters have been reported to increase the risk of superior venous cava (SVC) syndrome. This case report describes the development of acute SVC syndrome in a 28-year-old woman with end-stage renal disease implanted with a left-side hemodialysis reliable outflow graft and a right-side double lumen hemodialysis catheter via internal jugular veins. Her symptoms were not alleviated after catheter removal and systemic anticoagulation therapy. She was eventually treated with catheter-directed thrombolysis and a predischarge computer tomographic venogram on postthrombolytic procedure day 7 showed patent central veins and patient remained asymptomatic. This case demonstrates that catheter-directed thrombolysis can be safely employed to treat refractory catheter-induced acute SVC syndrome in end-stage renal disease patients.

  15. Hollow sphere ceramic particles for abradable coatings

    International Nuclear Information System (INIS)

    A hollow sphere ceramic flame spray powder is disclosed. The desired constituents are first formed into agglomerated particles in a spray drier. Then the agglomerated particles are introduced into a plasma flame which is adjusted so that the particles collected are substantially hollow. The hollow sphere ceramic particles are suitable for flame spraying a porous and abradable coating. The hollow particles may be selected from the group consisting of zirconium oxide and magnesium zirconate

  16. Retained Urethral Catheter Secondary to Placement in Proximal Ureter

    Directory of Open Access Journals (Sweden)

    Thomas B. McGregor

    2016-01-01

    Full Text Available We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter.

  17. Retained Urethral Catheter Secondary to Placement in Proximal Ureter.

    Science.gov (United States)

    McGregor, Thomas B; Sharda, Rajan

    2016-01-01

    We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter.

  18. Effect and Safety of Deep Needling and Shallow Needling for Functional Constipation

    OpenAIRE

    Wu, Jiani; Liu, Baoyan; Li, Ning; Sun, Jianhua; Wang, Lingling; Wang, Liping; Cai, Yuying; Ye, Yongming; Liu, Jun; Wang, Yang; Liu, Zhishun

    2014-01-01

    Abstract Aupuncture is widely used for functional constipation. Effect of acupuncture might be related to the depth of needling; however, the evidence is limited. This trial aimed to evaluate the effect and safety of deep needling and shallow needling for functional constipation, and to assess if the deep needling and shallow needling are superior to lactulose. We conducted a prospective, superiority-design, 5-center, 3-arm randomized controlled trial. A total of 475 patients with functional ...

  19. THE KISSING BALLOON TECHNIQUE WITH 2 OVER-THE-WIRE BALLOON CATHETERS THROUGH A SINGLE 8-FRENCH GUIDING CATHETER

    NARCIS (Netherlands)

    DENHEIJER, P; BERNINK, PJLM; VANDIJK, RB; TWISK, SPM; LIE, KI

    1991-01-01

    Some of the newer over-the-wire coronary angioplasty catheters have shaft sizes of 3.0 French (F) or less. The inner diameter of modern 8-F guiding catheters is large enough to accommodate two of such balloon catheters. We report a kissing balloon procedure with two over-the-wire catheters through a

  20. Hollow waveguide for urology treatment

    Science.gov (United States)

    Jelínková, H.; Němec, M.; Koranda, P.; Pokorný, J.; Kőhler, O.; Drlík, P.; Miyagi, M.; Iwai, K.; Matsuura, Y.

    2010-02-01

    The aim of our work was the application of the special sealed hollow waveguide system for the urology treatment - In our experimental study we have compared the effects of Ho:YAG (wavelength 2100 nm) and Er:YAG (wavelength 2940 nm) laser radiation both on human urinary stones (or compressed plaster samples which serve as a model) fragmentation and soft ureter tissue incision in vitro. Cyclic Olefin Polymer - coated silver (COP/Ag) hollow glass waveguides with inner and outer diameters 700 and 850 μm, respectively, were used for the experiment. To prevent any liquid to diminish and stop the transmission, the waveguide termination was utilized.

  1. Myocardium tissue ablation with hollow-waveguide-delivered near-infrared nanosecond laser pulses

    Science.gov (United States)

    Sato, Shunichi; Arai, Tsunenori; Shi, Yi-Wei; Matsuura, Yuji; Miyagi, Mitsunobu; Ashida, Hiroshi

    2001-06-01

    With 1064-nm, nanosecond laser pulses delivered from hollow waveguide, ablation characteristics of porcine myocardium tissue have been investigated in vitro. For the hollow waveguide a vacuum-cored scheme was introduced to suppress the laser-induced air breakdown that limited the available transmitted laser energy/power. The delivered laser pulse beam was focused with a collimation lens and a focusing lens, and it was shown that higher efficiency ablation was obtained when a focusing lens with a shorter focal length was used. Waveguide bending (bending angle 90 degree(s)C, bending radius approximately 50 cm) caused no deteriorating effect on the ablation characteristics for ablation energies up to approximately 60 mJ/pulse. It was demonstrated that deep and sharp ablated holes with aspect ratios > 8 was obtained with the hollow-waveguide-delivered laser pulses. It may be a realistic option to aim at using the present hollow waveguide system for trocar-based applications or replacing articulated mirror-based laser delivery systems. It is an important part of the future works to downsize the waveguide output unit for catheter-based applications.

  2. Using urokinase to restore patency in double lumen catheters.

    Science.gov (United States)

    Northsea, C

    1994-08-01

    All hemodialysis patients with temporary or permanent double lumen catheters are at risk for catheter occlusion. Clinical outcomes and cost-effectiveness of using urokinase, a thrombolytic agent, to declot occluded double lumen dialysis catheters were evaluated for 2 years. Patency was restored in 95 of 102 catheters. These data support the use of urokinase to safely and effectively restore patency, thereby extending the length of time a catheter can be used for dialysis.

  3. Venous port catheter dislocation as an unusual cause of pneumonia

    Directory of Open Access Journals (Sweden)

    Umut Serhat Sanrı

    2014-06-01

    Full Text Available The use of central venous port catheter is a very useful method for long-term therapy in patients with malignancy. Catheter insertion technique and maintenance of equipment is very important to the prevention of catheter-related complications. The most frequent complications are deep venous thrombosis, port infection, catheter obstruction. İn this article, pneumonia occurrence after chemotherapy infusion in a patient who has a completely extravasated central venous port catheter discussed.

  4. Biomechanical performance of new cardiovascular needles.

    Science.gov (United States)

    Thacker, J G; Ferguson, R E; Rodeheaver, G T; Edlich, R F

    2001-01-01

    Cardiovascular needles are now being manufactured from new stainless steel alloys containing high concentrations of nickel, Surgalloy and Ethalloy. The purpose of this study was to compare the biomechanical performance of a cardiovascular needle made of Surgalloy with a comparably sized needle made of Ethalloy. The parameters of biomechanical performance included sharpness, maintenance of sharpness, resistance to bending, and ductility. Because the biomechanical performance of these needles was remarkably similar, cardiovascular needles made of either the Surgalloy or Ethalloy alloys are recommended for cardiovascular surgery. PMID:11495105

  5. An Unusual Complication of Suprapubic Catheter Insertion

    Directory of Open Access Journals (Sweden)

    Krishnan Ananthakrishnan

    2006-01-01

    Full Text Available A patient who had a small bowel mesentery perforation following insertion of a suprapubic catheter (SPC is described. He had no bowel complaints immediately following the procedure, but presented 10 weeks later with insidious onset bowel obstruction due to the kink caused by the catheter. This complication occurred despite cystoscopy control and adequate bladder distension prior to the procedure. This isolated case illustrates the fact that regardless of the ease and frequency of SPC insertion, complications do occur.

  6. Rotational fluoroscopy and fine needle antegrade pyelography for determining kidney access in percutaneous nephrostomy

    International Nuclear Information System (INIS)

    Objective: To investigate the clinical value of fine needle antegrade pyelography combined with rotational fluoroscopy in determining the puncture track of percutaneous nephrostomy. Methods: A total of 543 patients with upper ureter calculus had percutaneous nephrostomy guided by C-arm fluoroscopy. After rotating fluoroscopy from anterior to lateral positions, fine needle percutaneous antegrade pyelography was performed under fluoroscopic guidance, which allowed three-dimensional mapping of the calculi, renal pelvis and their relationship. Using the nephroscope to select the optimal skin and calyceal puncture site by a 19G EV needle, the hydrophilic guide wire with or without a catheter was introduced and passed though the ureteric obstruction into the bladder. The punctured track was dilated and a nephrostomy tube was inserted. Results: Successful nephrostomy was performed on 542 patients. The nephrostomy tube was inserted into the ureter or renal pelvis in 539 cases and inserted into renal calices in 3 cases, with complications of renal pelvic tear in 5, pleura injury in 3, mild post-operative hemorrhage in 3 and delayed massive hemorrhage in 1. One patient died of heart failure after nephrolithotomy.. The total stone-free rate was 88% after the first nephrolithotomy. Conclusion: The use of fine needle antegrade pyelography combined with rotational fluoroscopy to determine the kidney access improves the success rate and reduces the incidence of complication. (authors)

  7. Determination of urethral catheter surface lubricity.

    Science.gov (United States)

    Kazmierska, Katarzyna; Szwast, Maciej; Ciach, Tomasz

    2008-06-01

    Device for in-vitro measurement of static and kinetic friction coefficient of catheter surface was developed. Tribometer was designed and constructed to work with exchangeable counter-faces (polymers, tissue) and various types of tubes, in wet conditions in order to mimic in-vivo process. Thus seven commercially available urethral catheters, made from vinyl polymers, natural latex with silicone coating, all-silicone or hydrogel coated, and one made from polyvinylchloride with polyurethane/polyvinylpyrrolidone hydrogel coating obtained in our laboratory, were tested against three various counter faces: polymethacrylate (organic glass), inner part of porcine aorta and porcine bladder mucosa. Additionally, the hydrophility/hydrophobity of tested catheters was stated via water wetting contact angle measurement. Super-hydrophilic biomaterials revealed low friction on tissue and hydrophobic counter-face; slightly hydrophobic showed higher friction in both cases, while more hydrophobic manifested low friction on tissue but high on hydrophobic polymer. The smoothest friction characteristic was achieved in all cases on tissue counter-faces. The measured values of the static coefficient of friction of catheters on bladder mucosa counter-face were as follows: the highest (0.15) for vinyl and siliconised latex catheters and 3 folds lower (0.05) for all-silicone ones. Hydrogel coated catheters exhibited the lowest static and kinetic friction factors. PMID:18071872

  8. Malfunctioning central venous catheters in children: a diagnostic approach

    Energy Technology Data Exchange (ETDEWEB)

    Barnacle, Alex; Arthurs, Owen J.; Roebuck, Derek; Hiorns, Melanie P. [Great Ormond Street Hospital, Radiology Department, London (United Kingdom)

    2008-04-15

    Central venous access is increasingly becoming the domain of the radiologist, both in terms of the insertion of central venous catheters (CVCs) and in the subsequent management of these lines. This article seeks to provide an overview of the CVC types available for paediatric patients and a more detailed explanation of the spectrum of complications that may lead to catheter malfunction. A standard catheter contrast study or 'linogram' technique is described. The normal appearances of such a study and a detailed pictorial review of abnormal catheter studies are provided, together with a brief overview of how information from catheter investigations can guide the management of catheter complications. (orig.)

  9. Dry needling - peripheral and central considerations.

    Science.gov (United States)

    Dommerholt, Jan

    2011-11-01

    Dry needling is a common treatment technique in orthopedic manual physical therapy. Although various dry needling approaches exist, the more common and best supported approach targets myofascial trigger points. This article aims to place trigger point dry needling within the context of pain sciences. From a pain science perspective, trigger points are constant sources of peripheral nociceptive input leading to peripheral and central sensitization. Dry needling cannot only reverse some aspects of central sensitization, it reduces local and referred pain, improves range of motion and muscle activation pattern, and alters the chemical environment of trigger points. Trigger point dry needling should be based on a thorough understanding of the scientific background of trigger points, the differences and similarities between active and latent trigger points, motor adaptation, and central sensitize application. Several outcome studies are included, as well as comments on dry needling and acupuncture.

  10. Usefulness of Core Needle Biopsy for Thyroid Nodules with Macrocalcifications: Comparison with Fine-Needle Aspiration

    OpenAIRE

    Yi, Kyung Sik; Kim, Ji-Hoon; Na, Dong Gyu; Seo, Hyobin; Min, Hye Sook; Won, Jae-Kyung; Yun, Tae Jin; Ryoo, Inseon; Kim, Su Chin; Choi, Seung Hong; Sohn, Chul-Ho

    2015-01-01

    Background: This study was performed to determine the benefits of core needle biopsy (CNB), as compared with fine-needle aspiration (FNA), for the diagnosis of thyroid nodules with macrocalcifications.

  11. Extraordinary Vessels Needling for Vascular Dementia

    Institute of Scientific and Technical Information of China (English)

    YU Jin; LAI Xin-sheng; HUANG Qiu-tang; XIAO Yuan-chun

    2003-01-01

    Purpose To observe the clinical efficacy of extraordinary vessels needling in treating vascular dementia. Method 39 cases vascular dementia were treated by acupoints selected from the eight extraordinary meridians and the time needling techniques such as eight methods of spiritual turtle, in accordance with time period and pattern identifition. Results 2 cases were cured, 30 cases improved and 7 cases failed; the total effective rate was 82.1%. Conclusion Extraordinary vessels needling has positive effects in treating vascular dementia.

  12. Exploration of New Electroacupuncture Needle Material

    OpenAIRE

    Sanghun Lee; Gwang-Ho Choi; Chang Hoon Lee; Yu Kyoung Kim; Saebhom Lee; Sungjin Cho; Sunhee Yeon; Sun-Mi Choi; Yeon-Hee Ryu

    2012-01-01

    Background. Electro Acupuncture (EA) uses the acupuncture needle as an electrode to apply low-frequency stimulation. For its safe operation, it is essential to prevent any corrosion of the acupuncture needle. Objective. The aim of this study is to find an available material and determine the possibility of producing a standard EA needle that is biocompatible. Methods. Biocompatibility was tested by an MTT assay and cytotoxicity testing. Corrosion was observed with a scanning electron microsco...

  13. Collimation with hollow electron beams

    CERN Document Server

    Stancari, G; Annala, G; Kuznetsov, G; Shiltsev, V; Still, D A; Vorobiev, L G

    2011-01-01

    A novel concept of controlled halo removal for intense high-energy beams in storage rings and colliders is presented. It is based on the interaction of the circulating beam with a 5-keV, magnetically confined, pulsed hollow electron beam in a 2-m-long section of the ring. The electrons enclose the circulating beam, kicking halo particles transversely and leaving the beam core unperturbed. By acting as a tunable diffusion enhancer and not as a hard aperture limitation, the hollow electron beam collimator extends conventional collimation systems beyond the intensity limits imposed by tolerable losses. The concept was tested experimentally at the Fermilab Tevatron proton-antiproton collider. The first results on the collimation of 980-GeV antiprotons are presented.

  14. Fabrication of Metallic Hollow Nanoparticles

    Science.gov (United States)

    Kim, Jae-Woo (Inventor); Choi, Sr., Sang H. (Inventor); Lillehei, Peter T. (Inventor); Chu, Sang-Hyon (Inventor); Park, Yeonjoon (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

    2016-01-01

    Metal and semiconductor nanoshells, particularly transition metal nanoshells, are fabricated using dendrimer molecules. Metallic colloids, metallic ions or semiconductors are attached to amine groups on the dendrimer surface in stabilized solution for the surface seeding method and the surface seedless method, respectively. Subsequently, the process is repeated with additional metallic ions or semiconductor, a stabilizer, and NaBH.sub.4 to increase the wall thickness of the metallic or semiconductor lining on the dendrimer surface. Metallic or semiconductor ions are automatically reduced on the metallic or semiconductor nanoparticles causing the formation of hollow metallic or semiconductor nanoparticles. The void size of the formed hollow nanoparticles depends on the dendrimer generation. The thickness of the metallic or semiconductor thin film around the dendrimer depends on the repetition times and the size of initial metallic or semiconductor seeds.

  15. Freehand biopsy guided by electromagnetic needle tracking

    DEFF Research Database (Denmark)

    Ewertsen, C; Nielsen, Marie Kristina Rue; Nielsen, M Bachmann

    2011-01-01

    To evaluate the overall accuracy and time spent on biopsy guided by electromagnetic needle tracking in a phantom compared with the standard technique of US-guided biopsy with an attached steering device. Furthermore, to evaluate off-plane biopsy guided by needle tracking.......To evaluate the overall accuracy and time spent on biopsy guided by electromagnetic needle tracking in a phantom compared with the standard technique of US-guided biopsy with an attached steering device. Furthermore, to evaluate off-plane biopsy guided by needle tracking....

  16. Cascade decays of hollow ions

    International Nuclear Information System (INIS)

    A multiple-electron-emission process for atoms with one or more inner-shell vacancies is treated using the radiative- and Auger-electron-emission cascade model, in which inner-shell holes are assumed to decay by sequentially emitting radiations and/or Auger electrons. Such hollow ions are produced by synchrotron irradiation of atomic targets and in ion-surface interactions with multiple-electron transfers. The final charge-state distribution is determined by the Auger and radiative branching ratios at each stage of the decay sequence. At intermediate stages of cascade, hollow ions with more than one hole in different ionization stages are created. The Ne, Mg, and Fe14+ ions with the initial 1s, 2s, and 2p vacancies are considered in detail, and the core charge dependence of the maximum charge state is studied. The hollow Mg ion with double initial 1s holes is analyzed, and the result compared with that for the case of one 1s hole. The peak is shifted more than two units to a higher degree of ionization. The correlated shake-off and shake-up multiple-electron processes are not considered, but they are expected to cause further shifts

  17. Everting (toposcopic) catheter for broad clinical application.

    Science.gov (United States)

    Shook, D R; Doppman, J L; Cattau, E L; Goldstein, S R

    1986-05-01

    The advanced development of the clinical everting (toposcopic) catheter is described. A detailed discussion of the design and outline of the fabrication techniques are followed by a thorough performance evaluation and summary of the first two clinical applications. The everting element is a low-durometer thermoplastic polyurethane elastomer. Surface treatments include the bonding of a hydrophilic polymeric coating, optimized for lubricity, to the sliding internal surfaces of the catheter. Eversion pressures and infusion/aspiration flow rates have been measured under various conditions and the infusate-in-blood mixing potential investigated. A preliminary assessment is given of the clinical performance of the catheter in the vascular delivery of chemotherapy and standard endoscopic retrograde cholangiopancreatography. PMID:3724105

  18. Microbiocidal effects of various taurolidine containing catheter lock solutions

    NARCIS (Netherlands)

    Olthof, E.D.; Nijland, R van; Gulich, A.F.; Wanten, G.J.A.

    2015-01-01

    BACKGROUND & AIMS: We have recently shown that a catheter lock solution containing taurolidine dramatically decreases catheter-related bloodstream infections (CRBSI) in patients on home parenteral nutrition (HPN) when compared to heparin. Since several taurolidine formulations are commercially avail

  19. Prevention of catheter-related Pseudomonas aeruginosa infection by levofloxacin-impregnated catheters in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    Yan Ping; Liu Wei; Kong Jinliang; Wu Hong; Chen Yiqiang

    2014-01-01

    Background Implanted medical catheter-related infections are increasing,hence a need for developing catheter polymers bonded to antimicrobials.We evaluated preventive effects of levofloxacin-impregnated catheters in catheterrelated Psuedomonas aeruginosa (strain PAO1) infection.Methods Drug release from levofloxacin-impregnated catheters was measured in vitro.Levofloxacin-impregnated catheters and polyvinyl chloride (PVC) catheters were immersed in 5 ml 50% Luria Bertani medium containing 108 CFU/ml Pseudomonas aeruginosa then incubated for 6,12,24 or 48 hours at 37℃ when bacteria adhering to the catheters and bacteria in the growth culture medium were determined.Impregnated and PVC catheters were singly implanted subcutaneously in mice,50 μl (107CFU) of PAO1 was injected into catheters.After the first and fifth days challenge,bacterial counts on implanted catheters and in surrounding tissues were determined microbiologically.Bacterial colonization and biofilm formation on implanted catheters were assessed by scanning electron microscopy.Results Drug release from levofloxacin-impregnated catheters was rapid.Levofloxacin-impregnated catheters had significantly fewer bacteria compared to PVC in vitro.After first and fifth day of challenge,no or significantly fewer bacteria adhered to impregnated catheters or in surrounding tissues compared to PVC.Scanning electron microscopical images after first day displayed from none to significantly fewer bacteria adhering to impregnated implanted catheters,compared to bacteria and microcolonies adhering to PVC catheters.After the fifth day,no bacteria were found on impregnated catheters,compared to clusters surrounding mucus-like substance and coral-shaped biofilms with polymorphonuclear leukocyte on PVC catheters.After the first day of challenge,secretion occurred in all implanted catheters with surrounding tissues mildly hyperaemic and swollen.After the fifth day,minute secretions inside impregnated catheters and no

  20. [Phlebitogenicity of venous catheters of Vialon].

    Science.gov (United States)

    Fassolt, A

    1985-12-01

    During three days 132 surgical patients with postoperative infusion treatment were checked on the frequency of venous reactions in the arms when catheters/cannulas of 4 different materials were used and the outcome compared. A significant result was obtained in connection with the I-cath catheter made of vialon (a polyurethanelike resin polymer) and the L-cath of polyurethane. Phlebitis was decreased to 27.3% resp. 24.2% - approximately half of its usual frequency - when I-cath of polyvinyl-chloride and FEP-teflon vasofix cannulas were applied (both 51.5%). The different predisposing factors of infusion phlebitis are under discussion. PMID:4093198

  1. Tetrahedral mesh for needle insertion

    OpenAIRE

    Syvertsen, Rolf Anders

    2007-01-01

    This is a Master’s thesis in how to make a tetrahedral mesh for use in a needle insertion simulator. It also describes how it is possible to make the simulator, and how to improve it to make it as realistic as possible. The medical simulator uses a haptic device, a haptic scene graph and a FEM for realistic soft tissue deformation and interaction. In this project a tetrahedral mesh is created from a polygon model, and then the mesh has been loaded into the HaptX haptic scene graph. The object...

  2. Force control of flexible catheter robots for beating heart surgery

    OpenAIRE

    Kesner, Samuel Benjamin; Howe, Robert D.

    2011-01-01

    Recent developments in cardiac catheter technology promise to allow physicians to perform most cardiac interventions without stopping the heart or opening the chest. However, current cardiac devices, including newly developed catheter robots, are unable to accurately track and interact with the fast moving cardiac tissue without applying potentially damaging forces. This paper examines the challenges of implementing force control on a flexible robotic catheter. In particular, catheter frictio...

  3. Preparation of titanium dioxide photocatalytic hollow spheres

    Institute of Scientific and Technical Information of China (English)

    PANG Xue-man; XU Ming-xia; HOU Feng; LI Ming-li

    2006-01-01

    With coaxial nozzle system,TiO2 hollow spheres were prepared and the optimum parameters of forming TiO2 hollow spheres were fix on as follows: acrylamide (AM) was used as monomer up to 30.3%,acetone was used as vesicant,the mass fraction of initiator was 0.4%,the forming temperature was in the range from 90 ℃ to 95 ℃. The photocatalistic performance of TiO2 hollow spheres was characterized by degradation of methyl orange. Compared with nano-TiO2 powders,hollow spheres can be recycled after cleanout and drying,taking on similar efficiency of photocatalistic.

  4. Autosizing Control Panel for Needle Bearing

    Directory of Open Access Journals (Sweden)

    Prof.A.R.Wadhekar,

    2016-02-01

    Full Text Available A needle roller bearing is a bearing which uses small cylindrical rollers. Bearings are used to reduce friction of any rotating surface. Needle bearings have a large surface in contact with the bearing outer surfaces as compared to ball bearings. There is less added clearance(Diameter of the shaft and the diameter of the bearing are different so they are much compact. The structure consists of a needle cage which contains the needle rollersthemselves and an outer race (The housing itself. Radial bearings are cylindrical and they use rollers parallel to the axis of the shaft. Radial pattern of needle are being used by thrust needles. Complement bearings have solid inner as well as outer rings and rib-guided cylindrical rollers. The bearings have the largest number of rolling elements and also have extremely high radial load carrying capacity and are suitable for compact designs.Needle roller bearings have relatively small diameter cylindrical rolling elements whose length is much larger than their diameter. As compared to other types of rolling bearings, needle roller bearings possess a small cross-sectional height and significant load-bearing capacity and rigidity relative to their volume. Also, because the inertial force acting on them is limited, needle bearings are an ideal choice for applications with oscillating motion. These bearings also work well in compact and lightweight machine designs and they serve as a ready replacement for sliding bearings. Needle bearings features are great rigidity, smaller cross-section, higher loadcarrying capacity, and has lower inertia forces that facilitate to size and weight reductions in machinery. Needle bearings are designed to stand in oscillation, performwell under any conditions, and interchange with the sliding of bearings.

  5. 21 CFR 870.1230 - Fiberoptic oximeter catheter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fiberoptic oximeter catheter. 870.1230 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1230 Fiberoptic oximeter catheter. (a) Identification. A fiberoptic oximeter catheter is a device used to estimate the...

  6. 21 CFR 868.5350 - Nasal oxygen catheter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nasal oxygen catheter. 868.5350 Section 868.5350...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5350 Nasal oxygen catheter. (a) Identification. A nasal oxygen catheter is a device intended to be inserted through a patient's nostril...

  7. Small Bowel Obstruction Due to Suprapubic Catheter Placement

    OpenAIRE

    Bonasso, Patrick C.; Brandon Lucke-Wold; Uzer Khan

    2016-01-01

    Suprapubic catheter placement has associated complications such as bowel injury, bladder injury, or bleeding. This case describes the management of an elderly patient who had suprapubic catheter placement complicated by small bowel obstruction. The catheter had continued production of urine. Further patient treatment required abdominal exploration and bowel resection.

  8. Small Bowel Obstruction Due to Suprapubic Catheter Placement

    Directory of Open Access Journals (Sweden)

    Patrick C. Bonasso

    2016-07-01

    Full Text Available Suprapubic catheter placement has associated complications such as bowel injury, bladder injury, or bleeding. This case describes the management of an elderly patient who had suprapubic catheter placement complicated by small bowel obstruction. The catheter had continued production of urine. Further patient treatment required abdominal exploration and bowel resection.

  9. Small Bowel Obstruction Due to Suprapubic Catheter Placement.

    Science.gov (United States)

    Bonasso, Patrick C; Lucke-Wold, Brandon; Khan, Uzer

    2016-07-01

    Suprapubic catheter placement has associated complications such as bowel injury, bladder injury, or bleeding. This case describes the management of an elderly patient who had suprapubic catheter placement complicated by small bowel obstruction. The catheter had continued production of urine. Further patient treatment required abdominal exploration and bowel resection. PMID:27335801

  10. Activity of sparfloxacin on Staphylococcus epidermidis attached to plastic catheters.

    Science.gov (United States)

    Pascual, A; García, I; Ramirez de Arellano, E; Perea, E J

    1995-08-01

    The activity of sparfloxacin on Staphylococcus epidermidis biofilms on different plastic catheters was evaluated. Sparfloxacin showed high bactericidal activity against S. epidermidis biofilms on Vialon and polyvinylchloride catheters. The combination of sparfloxacin with amikacin or rifampicin significantly increased its activity against bacterial biofilms on polyurethane and Teflon catheters. PMID:8522473

  11. Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid

    Science.gov (United States)

    ... Index A-Z Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid An ultrasound-guided thyroid biopsy ... Thyroid? What is Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid? During a fine needle aspiration ...

  12. Not to Knot a Catheter. Case Report of the Knotting of a Suprapubic Catheter

    Directory of Open Access Journals (Sweden)

    S. A. Farook

    2007-01-01

    Full Text Available A 20-month-old boy, who underwent left nephrectomy, had a suprapubic catheter inserted that knotted within the bladder. This case report identifies possible causes for such occurrences and how best to manage them.

  13. Not to Knot a Catheter. Case Report of the Knotting of a Suprapubic Catheter

    OpenAIRE

    Farook, S. A.; Kariholu, U.; Kousidis, G.; Powlis, M.

    2007-01-01

    A 20-month-old boy, who underwent left nephrectomy, had a suprapubic catheter inserted that knotted within the bladder. This case report identifies possible causes for such occurrences and how best to manage them.

  14. A comparison of the priming properties of two central venous catheters and one pulmonary artery catheter.

    Science.gov (United States)

    Sanderson, P M

    1995-01-01

    The time taken to prime the individual lumina of two multilumen central venous catheters (Viggo-Spectramed 14G 20 cm Hydrocath and Vialon 14G 20 cm Deltacath) and one pulmonary artery catheter (Viggo-Spectramed 110 cm 7.5F Pentacath) at flows between 5 ml.h-1 and 99 ml.h-1 is reported. The catheters supplied by different manufacturers but of identical length and gauge have significantly different priming times (p < 0.001). A protocol which may be used to prime the individual lumina of the three catheters studied is described. By means of an in vitro test the accuracy of this protocol is validated. PMID:7702147

  15. Catheter Removal versus Retention in the Management of Catheter-Associated Enterococcal Bloodstream Infections

    Directory of Open Access Journals (Sweden)

    Jonas Marschall

    2013-01-01

    Full Text Available BACKGROUND: Enterococci are an important cause of central venous catheter (CVC-associated bloodstream infections (CA-BSI. It is unclear whether CVC removal is necessary to successfully manage enterococcal CA-BSI.

  16. Encapsulation of dye molecules and nanoparticles in hollow organogel fibers of a nonchiral polyurethane model compound.

    Science.gov (United States)

    Khan, Mostofa Kamal; Sundararajan, Pudupadi

    2011-01-24

    We present the case of a nonchiral organogelator that forms hollow fibers and encapsulates silver nanoparticles (SNP) and a dye molecule. The biscarbamate molecule (a model compound for polyurethanes), which has two hydrogen-bonding motifs symmetrically attached to n-dodecyl side chains (C(12)), gels benzonitrile with hollow fibrillar morphology. The C(12) molecules form sheets that eventually wrap into hollow fibers to form the gel network. Herein, two-component gels were prepared with C(12) as one component and SNP, phthalocyanine (Pc), or perylene (Pe) as the other. Microscopic analysis and partial melting experiments confirmed the inclusion of the silver nanoparticles and phthalocyanine into the hollow fibers. On the other hand, Pe molecules tend to form crystals at the outer surface of the C(12) fibers, which results in a significant increase in the width of the gel fibers. This difference in the behavior of Pc and Pe molecules were accounted for by their crystal geometry and significantly different crystal growth rate compared with that of C(12) fiber formation in the gels. Pc crystallizes in a needle shape that facilitates occlusion in the gel fibers, whereas Pe forms large platelets. X-ray diffraction and spectroscopic analysis of the two-component gels along with their neat components confirmed that there was no change in the packing behavior of the Pc and Pe molecules in the gels. Therefore, these are examples of two-component physical gels in which the Pc crystals are occluded within the hollow fibers of C(12) by physical mixing of the components without the aid of any inter-molecular interactions between the different components. We have thus shown that lumen-loaded gel fibers with nanoparticles and dye molecules can be prepared by the two-component gel route, provided that the above growth rate, shape, and size conditions are satisfied. PMID:21243684

  17. [Fine needle aspiration cytology of mammography screening

    DEFF Research Database (Denmark)

    Engvad, B.; Laenkholm, A.V.; Schwartz, Thue W.;

    2009-01-01

    diagnostic classes were introduced. The aim of this study was to evaluate the quality assurance programme in a screening population to determine whether fine needle aspiration cytology (FNAC) as first choice remains a useful tool in the preoperative diagnostics, or if needle core biopsy should be the first...

  18. An Elementary Account of Needle Insertion

    Institute of Scientific and Technical Information of China (English)

    张文兵; 霍则军

    2004-01-01

    @@ Based on the authors' clinical and personal experiences, several pain-inducing factors easily to be ignored by the operators when quick needle insertion is applied, and the authors' first invented slow painless needle insertion method are introduced in the article.

  19. Needle-Tissue Interaction by Experiment

    NARCIS (Netherlands)

    Van Gerwen, D.J.

    2013-01-01

    Medical needles may not be very popular among patients, but they are exceptionally versatile instruments that have found their way into virtually every clinical intervention imaginable. However, despite their versatility, needles can be very difficult to use, and there is much room for improvement.

  20. Freehand biopsy guided by electromagnetic needle tracking

    DEFF Research Database (Denmark)

    Ewertsen, C; Nielsen, Marie Kristina Rue; Nielsen, M Bachmann

    2011-01-01

    To evaluate the overall accuracy and time spent on biopsy guided by electromagnetic needle tracking in a phantom compared with the standard technique of US-guided biopsy with an attached steering device. Furthermore, to evaluate off-plane biopsy guided by needle tracking....

  1. [Textual research on the fire needle and the fire needle therapy].

    Science.gov (United States)

    Liu, T; Zhu, J P; Zhang, Q C

    2016-03-01

    There are different names of the fire needle therapy in the Huang di nei jing (Inner Canon of Huangdi) such as Zu-zhen (), Cui-zhen (,), Fan-zhen (), Huo-cui (), Cui (,,), Cuici ,), Fan zhen jie ci (). It is claimed that the lance needle, the round sharp needle and the long needle recorded in this Classic are puncturing tools for the fire needle therapy. In the Eastern Han Dynasty, Zhang Zhongjing expanded the indications for the fire needle therapy and Huo-zhen () firstly appeared in the Jin kui yu han jing(Classic of the Jade Box and Golden Chamber). The application of the fire needle therapy had been further expanded to a lot of internal and external disorders form the Wei-Jin-Southern and Northern Dynasties to the Ming and Qing Dynasties. There are more detailed records on the manipulation and the tools of the fire needle therapy during this period. In the 1970s, Huo zhen liao fa () was proposed and still in use today. However the Bai-zhen (plain needle) in ancient literature is equal to the filiform needle and should not be regarded as the former name of the fire needle. PMID:27255194

  2. Concurrent use of pigtail and loop snare catheters for percutaneous retrieval of dislodged central venous port catheter.

    Science.gov (United States)

    Chuang, Ming-Tsung; Wu, Ding-Kwo; Chang, Cheng-Ang; Shih, Ming-Chen Paul; Ou-Yang, Fu; Chuang, Chien-Han; Tsai, Yi-Fan; Hsu, Jui-Sheng

    2011-11-01

    The purpose of this study was to report our experience of percutaneous retrieval of dislodged port catheters with concurrent use of pigtail and loop snare catheters. During a 5-year period at our institute (June 2005 to July 2010), a total of 23 dislodged port catheters were retrieved. The interval between port catheter implantation and dislodged catheter retrieval ranged from 43 days to 1,414 days (mean 586.7 days). The time of delayed retrieval ranged from 1 day to 45 days (mean 4.6 days). All dislodged catheters were retrieved with the concurrent use of pigtail and loop snare catheters via femoral venous route. The prevalence of port catheter dislodgement at our institute was 3.4%. All dislodged port catheters were removed successfully with pigtail and loop snare catheters together. No procedure-related complications were encountered, except for transient arrhythmia in two patients, which required no medication. In conclusion, the concurrent use of pigtail and loop snare catheters is a feasible and easy way for percutaneous retrieval of a dislodged central venous port catheter.

  3. Complications after placement of peritoneal catheter

    Directory of Open Access Journals (Sweden)

    Đurđević-Mirković Tatjana

    2011-01-01

    Full Text Available Introduction. Peritoneal dialysis is one of the modalities used for treatment of end-stage chronic kidney failure. Nowadays, this method is complementary to haemodialysis and renal transplantation. Owing to the rich vascularization of the peritoneum, it is used in the processes of osmosis and diffusion, enabling the removal of uremic material from the body. The procedure includes introduction of peritoneal fluid via the peritoneal catheter. Complications. The catheter is placed through the anterior abdominal wall with its tip positioned in the small pelvis. There are several techniques for catheter placement considered minimally invasive, which, however, may be associated with various complications. These complications can be divided into mechanical (catheter dysfunction, cuff protrusion, hernia, dialysate leaks, visceral perforation and infectious (early peritonitis, exit site or tunnel infection, surgical wounds. In most cases, such complications are rare and can be successfully managed using conservative therapy; however, in some situations severe complications can endanger the life of the patient. On-time recognition of complications, particularly in patients at risk, is of paramount importance for an effective treatment. The development of complications can increase the morbidity and the chance of treatment failure, and therefore transfer to haemodialysis. Conclusion. The preoperative evaluation and determination of the risk factors as well as the early recognition and adequate management of complications are essential in their prevention.

  4. The risks and benefits of suprapubic catheters.

    Science.gov (United States)

    Yates, Ann

    Suprapubic catheterisation can improve some patients' quality of life but the insertion procedure, as well as changing and managing the catheter, carry risks of infection and other negative patient outcomes. This article highlights the advantages and disadvantages, indications and contraindications, and the potential benefits, so health professionals can understand the relevant issues and assess and inform patients accordingly. PMID:27017651

  5. 21 CFR 874.4175 - Nasopharyngeal catheter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nasopharyngeal catheter. 874.4175 Section 874.4175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... intended for use in probing or dilating the eustachian tube. This generic type of device...

  6. Laser needle guide for the sonic flashlight.

    Science.gov (United States)

    Wang, David; Wu, Bing; Stetten, George

    2005-01-01

    We have extended the real-time tomographic reflection display of the Sonic Flashlight to a laser guidance system that aims to improve safety and accuracy of needle insertion, especially for deep procedures. This guidance system is fundamentally different from others currently available. Two low-intensity lasers are mounted on opposite sides of a needle aimed parallel to the needle. The needle is placed against a notch in the Sonic Flashlight mirror such that the laser beams reflect off the mirror to create bright red spots on the flat panel display. Due to diffuse reflection from these spots, the virtual image created by the flat panel display contains the spots, identifying the projected destination of the needle at its actual location in the tissue. We have implemented our design and validated its performance, identifying several areas for potential improvement. PMID:16685901

  7. Epidural catheter fragment entrapment: a case report

    Directory of Open Access Journals (Sweden)

    Mohammadi M

    2010-07-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Epidural catheters are seldom difficult to remove from patients. The breakage of the catheters is uncommon, troublesome and occasionally dangerous. "n"nCase presentation: A lumbar epidural catheter inserted in a 17 year-old man for applying anesthesia for internal fixation of femur fracture and subsequent postoperative epidural analgesia. In the third postoperative day, during unsuccessful attempt for removing the catheter, it was broken and was retained in his back. A CT- scan was performed and shows a fragment of catheter in the sub- laminar ligament between L3 and L4 without any connection with epidural space. As the patient had no complaint the fractured fragment was left in site and he was just followed up in the clinic."n"nConclusion: The knowledge of practical method in locating the retained epidural catheter, and the indication for surgical removal are very important. CT- scan is useful in showing the mechanism and locating the epidural catheter entrapment and facilitating surgical follow-up.

  8. Repositioning of malpositioned or flipped central venous catheters

    Energy Technology Data Exchange (ETDEWEB)

    Thalhammer, A.; Jacobi, V.; Balzer, J.; Vogl, T.J. [Institute for Diagnostic and Interventional Radiology, Central Radiology Clinic, J.W. Goethe University, Frankfurt am Main (Germany)

    2002-03-01

    Primary misplaced or secondary flipped implanted catheters are located mostly in the right jugular vein. We demonstrate an effective method to replace fix implanted catheters such as Ports, Grochomg or Hickman catheters. Using a femoral venous approach, replacement into the superior vena cava can easily be done with a Sidewinder 1 catheter which is hooked over the misplaced central venous approach. In all our patients the method was successful. The repositioning technique described is simple, fast and has low costs. We can keep sterile conditions and do not need to solve the catheters' fixation. (orig.)

  9. Hollow cathode lamp-construction aspects

    International Nuclear Information System (INIS)

    The hollow cathode discharge is a source used for absorption and fluorescence atomic spectrophotometry. In this paper various aspect like construction, cleanliness and operation have been described. The life time of the hollow cathode discharge for specific current is about 500 hs. The range of current for the non significant self-absorption of the recommended wavelenght has been determinated. (Author)

  10. Traumatic and nontraumatic perforation of hollow viscera.

    Science.gov (United States)

    Espinoza, R; Rodríguez, A

    1997-12-01

    Hollow viscus injuries are usually managed with few complications. However, if their diagnosis is delayed, or if reparative suture closure should fail, the patient is placed at risk of multiple organ failure. This article presents diagnostic approaches, emphasizing imaging modalities, and therapeutic strategies for three clinical scenarios of hollow viscus perforation: 1) acute appendicitis, 2) gastroduodenal peptic ulcer disease, and 3) trauma.

  11. Hollow sucker rod for PCP systems

    Energy Technology Data Exchange (ETDEWEB)

    Villasante, J.A.; Ernst, H.A. [Tenaris Research and Development, Campana (Argentina)

    2008-07-01

    This paper described a new hollow sucker rod technology designed for use with progressive cavity pumps (PCPs). The technology provided a high torque load to yielding ratio, as well as high backspin resistance and pumping rates. The technology was also designed to allow for the injection of other fluids such as corrosion inhibitors or diluents via its hollow sucker rod. Torsion, axial, and bending load stress analyses were conducted to determine critical zones in a top hollow rod connection at the well head and a bottom hollow rod connection at the well bottom. The study showed that the ratio between the equivalent stress and ultimate tensile stress was a function of torsional load. Backspin analyses were conducted to determine the release of energy accumulated in the hollow rod and traditional pumping system. The evaluation showed that the elastic torsional deformation was lower in the hollow rod system, while backspin resistance was higher. Multiple make and break operations were conducted to determine torsional load values. Results from the study were used to optimize the hollow rod technology. It was concluded that the hollow sucker rod system is now being used in various configurations at sites around the world. 8 tabs., 14 figs.

  12. Radiologically placed tunneled peritoneal catheter in palliation of malignant ascites

    Energy Technology Data Exchange (ETDEWEB)

    Akinci, Devrim; Erol, Bekir; Ciftci, Tuerkmen T. [Hacettepe University, Faculty of Medicine, Department of Radiology, 06100 Ankara (Turkey); Akhan, Okan, E-mail: akhano@tr.net [Hacettepe University, Faculty of Medicine, Department of Radiology, 06100 Ankara (Turkey)

    2011-11-15

    The purpose of this study was to evaluate retrospectively the safety and effectiveness of radiologically placed tunneled peritoneal catheter in palliation of malignant ascites. Between July 2005 and June 2009, 41 tunneled peritoneal catheters were placed under ultrasonographic and fluoroscopic guidance in 40 patients (mean age, 55 years; 22 women) who had symptomatic malignant ascites. No procedure related mortality was observed. Major complication occurred in one patient (2.5%) in the form of serious bacterial peritonitis that necessitated catheter removal. Minor complications such as minor bacterial peritonitis, catheter dislodgement, tunnel infection, and catheter blockage occurred in 11 patients (27.5%). The mean duration of survival after catheter placement was 11.8 weeks. All patients expired of their primary malignancies in the follow-up. Radiologically placed tunneled peritoneal catheter is safe and effective in palliation of symptomatic malignant ascites.

  13. The bowed catheter sign: a risk for pericardial tamponade

    Energy Technology Data Exchange (ETDEWEB)

    Towbin, Richard [Phoenix Children' s Hospital, Department of Radiology, Phoenix, AZ (United States)

    2008-03-15

    The use of a central venous catheter (CVC) has become commonplace in the care of children with a wide variety of medical and surgical problems. Complications resulting from the insertion of these catheters are well recognized and can be life-threatening. When a temporary CVC or other catheter is inserted into the central venous system it is secured to the skin with a combination of sutures and sterile dressing. This fixes the catheter in place and does not allow it to retract, thereby putting pressure on the right atrial wall via the catheter tip if it is too long. The probability of wall penetration is increased if a catheter or device is tapered at the point of contact. The purpose of this case report is to present the bowed catheter sign and to review the anatomy of the cavotricuspid isthmus, a possible predisposing factor to cardiac perforation and tamponade. (orig.)

  14. Apical pressures developed by needles for canal irrigation.

    Science.gov (United States)

    Bradford, C E; Eleazer, P D; Downs, K E; Scheetz, J P

    2002-04-01

    Drying instrumented canals with pressurized air may result in patient morbidity or even fatality. Low pressure and side vent needles have been suggested to lessen the danger. This study observed apical pressures from different needles inserted deeply into small round and ovoid canals as instrumentation progressed. Low-pressure (5 psi) air was injected through the needles, and apical pressures were recorded after each instrument. Pressures varied greatly within each test group. Generalities that can be drawn are that binding the needle within the canal gives higher pressures than with the needle slightly short of binding and that pressures were higher with apexes instrumented to size 30 and higher. With the needle tightly bound, neither needle size, needle design, nor canal shape resulted in statistically significant mean pressure differences. With the needle slightly withdrawn, larger bore needles gave higher pressures than small diameter needles. Caution is advised with the clinical use of pressurized air in the drying of root canals. PMID:12043877

  15. Use of optimized ultrasound axis along with marked introducer needle to prevent mechanical complications of internal jugular vein catheterization

    Directory of Open Access Journals (Sweden)

    Tanmoy Ghatak

    2013-01-01

    Full Text Available Internal jugular vein (IJV catheterization is a routine technique in the intensive care unit. Ultrasound (US guided central venous catheter (CVC insertion is now the recommended standard. However, mechanical complications still occur due to non-visualization of the introducer needle tip during US guidance. This may result in arterial or posterior venous wall puncture or pneumothorax. We describe a new technique of (IJV catheterization using US, initially the depth of the IJV from the skin is measured in short-axis and then using real time US long-axis view guidance a marked introducer needle is advanced towards the IJV to the defined depth measured earlier in the short axis and the IJV is identified, assessed and cannulated for the CVC insertion. Our technique is simple and may reduce mechanical complications of US guided CVC insertion.

  16. The Biological Safety of Stainless Steel Needles Used in Warm-Needling

    Directory of Open Access Journals (Sweden)

    Sabina Lim

    2010-01-01

    Full Text Available Warm-needling (also called thermo-acupuncture is a combination of acupuncture and moxibustion. Due to the intense heat involved, there have been concerns over the biological safety of the acuneedles used in the treatment. This paper reports two phases of a safety test. For a preliminary test, we compared the temperature change patterns of stainless steel (SS304 needles and traditional gold alloy needles, which have been increasingly replaced by the former. To verify the effects of the presence of coating materials, the main test involved three different kinds of SS304: silicone-coated, salicylic acid-coated and non-coated needles. Each group of needles was tested for pH level, heavy metals and UV absorbance spectrum along with biological tests on the cytotoxicity and hemolysis of the needle. All the tests on the extractants from the needles were negative. In the biological tests, each test result showed a significant difference from the positive control samples, while no significant difference was observed compared with the negative control samples. In the hemolysis tests, all samples satisfied the Korean Government Standards. All the results suggest that SS304 needles are biologically safe to be used in warm-needling, though they can be improved to perform as well as the gold alloy needles in terms of temperature fluctuations.

  17. Effect of needle tract bleeding on occurrence of pneumothorax after transthoracic needle biopsy

    International Nuclear Information System (INIS)

    Purpose: Occasionally bleeding along the needle trajectory is observed at post-biopsy computed tomographic sections. This study was designed to evaluate the possible effect of needle tract bleeding on the occurrence of pneumothorax and on requirement of chest tube insertion. Materials and methods: Two hundred eighty-four needle biopsies performed in 275 patients in whom the needle traversed the aerated lung parenchyma were retrospectively reviewed. Bleeding along the needle tract, occurrence of pneumothorax and need for chest tube insertion, type and size of the needle, size of the lesion, length of the lung traversed by the needle, presence or absence of emphysema were noted. Effect of these factors on the rate of pneumothorax and needle-tract bleeding was evaluated. The data were analyzed by χ2 test. Results: Pneumothorax developed in 100 (35%) out of 284 procedures requiring chest tube placement in 16 (16%). Variables that were significantly associated with an increased risk of pneumothorax were depth of the lesion (P 0.05). However, analysis of the relation between length of lung traversed by the needle, tract-bleeding and pneumothorax rate indicated that tract-bleeding had a preventive effect on development of pneumothorax (P 0.05). Conclusion: Bleeding in the needle tract has a preventive effect on the occurrence of the pneumothorax in deep-seated lesions and in the presence of emphysema, although it does not affect the overall rate of pneumothorax

  18. Percutaneous Placement of Central Venous Catheters: Comparing the Anatomical Landmark Method with the Radiologically Guided Technique for Central Venous Catheterization Through the Internal Jugular Vein in Emergent Hemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Koroglu, M.; Demir, M.; Koroglu, B.K.; Sezer, M.T.; Akhan, O.; Yildiz, H.; Yavuz, L.; Baykal, B.; Oyar, O. [Suleyman Demirel Univ., Isparta (Turkey). Depts. of Radiology, Internal Medicine and Anesthesiology

    2006-02-15

    Purpose: To compare the success and immediate complication rates of the anatomical landmark method (group 1) and the radiologically (combined real-time ultrasound and fluoroscopy) guided technique (group 2) in the placement of central venous catheters in emergent hemodialysis patients. Material and Methods: The study was performed prospectively in a randomized manner. The success and immediate complication rates of radiologically guided placement of central venous access catheters through the internal jugular vein (n = 40) were compared with those of the anatomical landmark method (n 40). The success of placement, the complications, the number of passes required, and whether a single or double-wall puncture occurred were also noted and compared. Results: The groups were comparable in age and sex. The indication for catheter placement was hemodialysis access in all patients. Catheter placement was successful in all patients in group 2 and unsuccessful in 1 (2.5%) patient in group 1. All catheters functioned adequately and immediately after the placement (0% initial failure rate) in group 2, but 3 catheters (7.5% initial failure rate) were non-functional just after placement in group 1. The total number of needle passes, double venous wall puncture, and complication rate were significantly lower in group 2. Conclusion: Percutaneous central venous catheterization via the internal jugular vein can be performed by interventional radiologists with better technical success rates and lower immediate complications. In conclusion, central venous catheterization for emergent dialysis should be performed under both real-time ultrasound and fluoroscopic guidance.

  19. Evaluation of the friction coefficient, the radial stress, and the damage work during needle insertions into agarose gels.

    Science.gov (United States)

    Urrea, Fabián A; Casanova, Fernando; Orozco, Gustavo A; García, José J

    2016-03-01

    Agarose hydrogels have been extensively used as a phantom material to mimic the mechanical behavior of soft biological tissues, e.g. in studies aimed to analyze needle insertions into the organs producing tissue damage. To better predict the radial stress and damage during needle insertions, this study was aimed to determine the friction coefficient between the material of commercial catheters and hydrogels. The friction coefficient, the tissue damage and the radial stress were evaluated at 0.2, 1.8, and 10mm/s velocities for 28, 30, and 32 gauge needles of outer diameters equal to 0.36, 0.31, and 0.23mm, respectively. Force measurements during needle insertions and retractions on agarose gel samples were used to analyze damage and radial stress. The static friction coefficient (0.295±0.056) was significantly higher than the dynamic (0.255±0.086). The static and dynamic friction coefficients were significantly smaller for the 0.2mm/s velocity compared to those for the other two velocities, and there was no significant difference between the friction coefficients for 1.8 and 10mm/s. Radial stress averages were 131.2±54.1, 248.3±64.2, and 804.9±164.3Pa for the insertion velocity of 0.2, 1.8, and 10mm/s, respectively. The radial stress presented a tendency to increase at higher insertion velocities and needle size, which is consistent with other studies. However, the damage work did not show to be a good predictor of tissue damage, which appears to be due to simplifications in the analytical model. Differently to other approaches, the method proposed here based on radial stress may be extended in future studies to quantity tissue damage in vivo along the entire needle track. PMID:26700572

  20. Fabrication of functional hollow carbon spheres with large hollow interior as active colloidal catalysts

    Institute of Scientific and Technical Information of China (English)

    Qiang Sun; Guanghui Wang; Wencui Li; Xiangqian Zhang; Anhui Lu

    2012-01-01

    In this study,we have established a facile method to synthesize functional hollow carbon spheres with large hollow interior,which can act as active colloidal catalysts.The method includes the following steps:first,hollow polymer spheres with large hollow interior were prepared using sodium oleate as the hollow core generator,and 2,4-dihydroxybenzoic acid and hexamethylene tetramine (HMT) as the polymer precursors under hydrothermal conditions; Fe3+ or Ag+ cations were then introduced into the as-prepared hollow polymer spheres through the carboxyl groups; finally,the hollow polymer spheres can be pseudomorphically converted to hollow carbon spheres during pyrolysis process,meanwhile iron or silver nanoparticles can also be formed in the carbon shell simultaneously.The structures of the obtained functional hollow carbon spheres were characterized by TEM,XRD,and TG.As an example,Ag-doped hollow carbon spheres were used as colloid catalysts which showed high catalytic activity in 4-nitrophenol reduction reaction.

  1. Distribution of elements in needles of Pinus massoniana (Lamb.) was uneven and affected by needle age

    International Nuclear Information System (INIS)

    Macronutrients (P, S, K, Na, Mg, Ca), heavy metals (Fe, Zn, Mn, Cu, Pb, Cr, Ni, Cd) and Al concentrations as well as values of Ca/Al in the tip, middle, base sections and sheaths of current year and previous year needles of Pinus massoniana from Xiqiao Mountain were analyzed and the distribution patterns of those elements were compared. The results indicated that many elements were unevenly distributed among the different components of needles. Possible deficiency of P, K, Ca, Mn and Al toxicity occurred in needles under air pollution. Heavy metals may threaten the health of Masson pine. Needle sheaths were good places to look for particulate pollutants, in this case including Fe, Cu, Zn, Pb, Cr, Cd and Al. - Pine needle sections as bioindicator for heavy metals and nutrient deficiency particularly needle sheath for particle pollutants

  2. Pine needle abortion biomarker detected in bovine fetal fluids

    Science.gov (United States)

    Pine needle abortion is a naturally occurring condition in free-range cattle caused by the consumption of pine needles from select species of cypress, juniper, pine, and spruce trees. Confirmatory diagnosis of pine needle abortion has previously relied on a combined case history of pine needle cons...

  3. Biological safety evaluation of the modified urinary catheter

    Energy Technology Data Exchange (ETDEWEB)

    Kowalczuk, Dorota, E-mail: dorota.kowalczuk@umlub.pl [Department of Medicinal Chemistry, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin (Poland); Przekora, Agata; Ginalska, Grazyna [Department of Biochemistry and Biotechnology, Medical University of Lublin, Chodzki 1, 20-093 Lublin (Poland)

    2015-04-01

    The purpose of this study was to evaluate in vitro safety of the novel tosufloxacin (TOS)-treated catheters with the prolonged antimicrobial activity. The test samples of silicone latex catheter were prepared by the immobilization of TOS on chitosan (CHIT)-coated catheter by means of covalent bonds and non-covalent interactions. Each step of the modification process of catheter surface was observed using ATR–Fourier transform infrared spectroscopy. In vitro cytotoxicity of the modified and unmodified catheters was assessed by direct and indirect tests in accordance with ISO standards using green monkey kidney (GMK) cell line. The MTT, lactate dehydrogenase activity (LDH), WST-8, Sulforhodamine B (SRB) test results and microscopic observation clearly indicated that unmodified silicone latex catheters decrease cell metabolic activity, act as a cytotoxic agent causing cell lysis and induce cell death through necrotic or apoptotic process. We suggest that chitosan coat with TOS immobilized limits leaching of harmful agents from silicone latex material, which significantly enhances survivability of GMK cells and therefore is quite a good protection against the cytotoxic effect of this material. - Highlights: • Characterization of the novel antimicrobial urinary catheters • Monitoring of the catheter modification by FTIR analysis • Confirmation of high cytotoxicity of latex-based catheter used in urological practice • Chitosan-coated and tosufloxacin-treated catheter is less toxic than the untreated one. • The proposed surface modification protects cells against latex-induced death.

  4. Radiologic Placement of Tunneled Central Venous Catheters in Pediatric Patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ji; Song, Soon Young; Cho, On Koo; Koh, Byung Hee; Kim, Yong Soo; Jeong, Woo Kyoung; Lee, Yong Ho [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2010-08-15

    We evaluated the technical success and complication rates associated with the radiological placement of tunneled central venous catheters in pediatric patients. Between May 1, 2005 and March 31, 2008, a total of 46 tunneled central venous catheters were placed in 34 children (M:F = 22:12; mean age, 9.9 years [9 months to 16.8 years]). All procedures were performed under ultrasonographic and fluoroscopic guidance. Follow-up data were obtained through the retrospective review of the medical records. We used the Kaplan-Meier survival method for the evaluation of survival rate of the catheters. All procedures were technically successful. The observed periprocedural complications included hematoma formation in three patients. The mean catheter life was 189.3 days (total, 8710 days; range, 7-810). Catheters were removed due to death (n=9), the end of treatment (n=8), catheter sepsis (n=4), malfunction (n=8), and accidental removal (n=4). The rate of catheter sepsis and malfunction was 0.459 and 0.919 for every 1000 catheter days, respectively. The expected mean catheter life was 479.6 days as per the Kaplan- Meier analysis. The results suggest that the radiologic placement of a tunneled central venous catheter is an effective technique with a high technical success rate and low complication rate.

  5. Hollow Micro-/Nanostructures: Synthesis and Applications

    KAUST Repository

    Lou, Xiong Wen (David)

    2008-11-03

    Hollow micro-nanostructures are of great interest in many current and emerging areas of technology. Perhaps the best-known example of the former is the use of fly-ash hollow particles generated from coal power plants as partial replacement for Portland cement, to produce concrete with enhanced strength and durability. This review is devoted to the progress made in the last decade in synthesis and applications of hollow micro-nanostructures. We present a comprehensive overview of synthetic strategies for hollow structures. These strategies are broadly categorized into four themes, which include well-established approaches, such as conventional hard-templating and soft-templating methods, as well as newly emerging methods based on sacrificial templating and template-free synthesis. Success in each has inspired multiple variations that continue to drive the rapid evolution of the field. The Review therefore focuses on the fundamentals of each process, pointing out advantages and disadvantages where appropriate. Strategies for generating more complex hollow structures, such as rattle-type and nonspherical hollow structures, are also discussed. Applications of hollow structures in lithium batteries, catalysis and sensing, and biomedical applications are reviewed. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA,.

  6. Distributed pressure sensors for a urethral catheter.

    Science.gov (United States)

    Ahmadi, Mahdi; Rajamani, Rajesh; Timm, Gerald; Sezen, A S

    2015-08-01

    A flexible strip that incorporates multiple pressure sensors and is capable of being fixed to a urethral catheter is developed. The urethral catheter thus instrumented will be useful for measurement of pressure in a human urethra during urodynamic testing in a clinic. This would help diagnose the causes of urinary incontinence in patients. Capacitive pressure sensors are fabricated on a flexible polyimide-copper substrate using surface micromachining processes and alignment/assembly of the top and bottom portions of the sensor strip. The developed sensor strip is experimentally evaluated in an in vitro test rig using a pressure chamber. The sensor strip is shown to have adequate sensitivity and repeatability. While the calibration factors for the sensors on the strip vary from one sensor to another, even the least sensitive sensor has a resolution better than 0.1 psi. PMID:26738054

  7. Pancreas tumor interstitial pressure catheter measurement

    Science.gov (United States)

    Nieskoski, Michael D.; Gunn, Jason; Marra, Kayla; Trembly, B. Stuart; Pogue, Brian W.

    2016-03-01

    This paper highlights the methodology in measuring interstitial pressure in pancreatic adenocarcinoma tumors. A Millar Mikrotip pressure catheter (SPR-671) was used in this study and a system was built to amplify and filter the output signal for data collection. The Millar pressure catheter was calibrated prior to each experiment in a water column at 37°C, range of 0 to 60 inH2O (112 mmHg), resulting in a calibration factor of 33 mV / 1 inH2O. The interstitial pressures measured in two orthotopically grown pancreatic adenocarcinoma tumor were 57 mmHg and 48 mmHg, respectively. Verteporfin uptake into the pancreatic adenocarcinoma tumor was measured using a probe-based experimental dosimeter.

  8. Monopole antennas for microwave catheter ablation

    Energy Technology Data Exchange (ETDEWEB)

    Labonte, S.; Blais, A.; Legault, S.R.; Ali, H.O.; Roy, L. [Univ. of Ottawa, Ontario (Canada). Dept. of Electrical Engineering

    1996-10-01

    The authors study the characteristics of various monopole antennas for microwave catheter ablation of the endocardium. The investigation is done with a computer model based on the finite-element method in the frequency domain. Three monopole geometries are considered: open-tip, dielectric-tip, and metal-tip. Calculations are made for the magnetic field, the reflection coefficient and the power deposition pattern of the antennas immersed in normal saline. The theoretical results are compared with measurements performed on prototypes and good agreement is obtained. The antenna characteristics suggest that the metal-tip monopole best fulfills the requirements of catheter ablation. The computer model is then used to compare metal-tip monopoles of different dimensions and to determine design trade-offs.

  9. Incidence of phlebitis associated with the use of peripheral IV catheter and following catheter removal

    Science.gov (United States)

    Urbanetto, Janete de Souza; Peixoto, Cibelle Grassmann; May, Tássia Amanda

    2016-01-01

    ABSTRACT Objective: to investigate the incidence of phlebitis and its association with risk factors when using peripheral IV catheters (PIC) and following their removal - (post-infusion phlebitis) in hospitalized adults. Method: a cohort study of 171 patients using PIC, totaling 361 punctures. Sociodemographic variables and variables associated with the catheter were collected. Descriptive and analytical statistical analyses were performed. Results: average patient age was 56.96 and 51.5% of the sample population was male. The incidence of phlebitis was 1.25% while using PIC, and 1.38% post-infusion. The incidence of phlebitis while using PIC was associated with the length of time the catheter remained in place, whereas post-infusion phlebitis was associated with puncture in the forearm. Ceftriaxone, Clarithromycin and Oxacillin are associated with post-infusion phlebitis. Conclusions: this study made it possible to investigate the association between risk factors and phlebitis during catheter use and following its removal. The frequency of post-infusion phlebitis was larger than the incidence of phlebitis with the catheter in place, with Phlebitis Grade III and II being the most frequently found in each of these situations, respectively. Aspects related to post-infusion phlebitis can be explained, given the limited number of studies addressing this theme from this perspective. PMID:27508916

  10. Transpleural central venous catheter discovered during thoracotomy

    Directory of Open Access Journals (Sweden)

    Ashima Malhotra

    2014-01-01

    Full Text Available We report an uncommon complication of subclavian central venous catheterization, discovered at thoracotomy. The central venous catheter (CVC was placed by left infraclavicular route after induction of general anesthesia. CVC was secured after aspiration of blood and satisfactory central venous tracing. On thoracotomy, CVC was noticed to traverse the pleural cavity while the tracing was normal. CVC was thus removed consequent to which bleeding from each puncture site was noticed, that were secured surgically.

  11. Electromagnetic tracking and steering for catheter navigation

    OpenAIRE

    O'Donoghue, Kilian

    2014-01-01

    This thesis explores the use of electromagnetics for both steering and tracking of medical instruments in minimally invasive surgeries. The end application is virtual navigation of the lung for biopsy of early stage cancer nodules. Navigation to the peripheral regions of the lung is difficult due to physical dimensions of the bronchi and current methods have low successes rates for accurate diagnosis. Firstly, the potential use of DC magnetic fields for the actuation of catheter devices with ...

  12. Robotic Catheters for Beating Heart Surgery

    OpenAIRE

    Kesner, Samuel Benjamin

    2011-01-01

    Compliant and flexible cardiac catheters provide direct access to the inside of the heart via the vascular system without requiring clinicians to stop the heart or open the chest. However, the fast motion of the intracardiac structures makes it difficult to modify and repair the cardiac tissue in a controlled and safe manner. In addition, rigid robotic tools for beating heart surgery require the chest to be opened and the heart exposed, making the procedures highly invasive. The novel robot...

  13. Hollow Core, Whispering Gallery Resonator Sensors

    CERN Document Server

    Ward, Jonathan M; Chormaic, Síle Nic

    2014-01-01

    A review of hollow core whispering gallery resonators (WGRs)is given. After a short introduction to the topic of whispering gallery resonators we provide a description of whispering gallery modes in hollow or liquid core WGRs. Next, whispering gallery mode (WGM) sensing mechanisms are outlined and some fabrication methods for microbubbles, microcapillaries and other tubular WGM devices are discussed. We then focus on the most common applications of hollow core WGRs, namely refractive index and temperature sensing, gas sensing, force sensing, biosensing, and lasing. The review highlights some of the key papers in this field and gives the reader a general overview of the current state-of-the-art.

  14. A Multi-Layered Needle Injection Simulator.

    Science.gov (United States)

    Laufer, Shlomi; Kempton, Steve J; Maciolek, Kimberly; Terry, Aliyya; Ray, Rebeca D; Pugh, Carla M; Afifi, Ahmed M

    2016-01-01

    Insuring correct needle location is crucial in many medical procedures. This can be even more challenging for physicians injecting in a new location for the first time. Since they do not necessarily know how the tissue is supposed to feel, finding the correct location and correct depth can be difficult. In this study we designed a simulator for training needle injection. The simulator was fabricated to give a realistic feeling of injecting Botox® in the temporalis and the semispinalis muscles as part of migraine treatment. In addition the simulator provided real-time feedback of correct needle location. Nine residents and medical students evaluated the simulator. They made several errors that were corrected real time using the real time feedback provided. They found the simulator to be very useful and that the training significantly improved their confidence. The methods described in this study can easily be implemented for developing needle injection simulators for other anatomical locations.

  15. Biopsy needle detection in transrectal ultrasound.

    Science.gov (United States)

    Ayvaci, Alper; Yan, Pingkun; Xu, Sheng; Soatto, Stefano; Kruecker, Jochen

    2011-01-01

    Using the fusion of pre-operative MRI and real time intra-procedural transrectal ultrasound (TRUS) to guide prostate biopsy has been shown as a very promising approach to yield better clinical outcome than the routinely performed TRUS only guided biopsy. In several situations of the MRI/TRUS fusion guided biopsy, it is important to know the exact location of the deployed biopsy needle, which is imaged in the TRUS video. In this paper, we present a method to automatically detect and segment the biopsy needle in TRUS. To achieve this goal, we propose to combine information from multiple resources, including ultrasound probe stability, TRUS video background model, and the prior knowledge of needle orientation and position. The proposed algorithm was tested on TRUS video sequences which have in total more than 25,000 frames. The needle deployments were successfully detected and segmented in the sequences with high accuracy and low false-positive detection rate.

  16. Fabricating a hollow bulb obturator

    Directory of Open Access Journals (Sweden)

    Fatih Sari

    2012-01-01

    Full Text Available

    Obturators are generally used in the rehabilitation of the maxillectomy defects. Ideally, obturators should be light, properly fit and construction should be made easily. By decreasing the weight of the prosthesis, the retention and stability may be optimized to allow the obturator for function comfortably during mastication, phonation, and deglutition. In this case, a 65-year-old male patient underwent surgical removal of left part of the maxilla due to the squamous cell carcinoma. In this technique fabrication of a hollow bulb obturator prosthesis as a single unit in heat-cured acrylic resin using a single-step flasking procedure was described. The patient’s functional and esthetic expectations were satisfied.

  17. Finite element model of needle electrode sensitivity

    Science.gov (United States)

    Høyum, P.; Kalvøy, H.; Martinsen, Ø. G.; Grimnes, S.

    2010-04-01

    We used the Finite Element (FE) Method to estimate the sensitivity of a needle electrode for bioimpedance measurement. This current conducting needle with insulated shaft was inserted in a saline solution and current was measured at the neutral electrode. FE model resistance and reactance were calculated and successfully compared with measurements on a laboratory model. The sensitivity field was described graphically based on these FE simulations.

  18. Needle Insertion with Duty-Cycled Rotation into Multiple Media

    OpenAIRE

    Lehocky, Craig A.; Riviere, Cameron N.

    2012-01-01

    Thin, flexible needles can be steered along nonlinear paths to reach deep anatomical structures within the human body. This study builds upon previous work involving steering of bevel-tipped needles by inserting while rotating in a duty-cycled fashion. Here we investigate how needle material and radius, duty cycle, and tissue stiffness affect needle curvature. Needles were inserted into media while rotated at a specified duty cycle and the curvature was measured. A linear relationship between...

  19. Dry needling versus acupuncture: the ongoing debate.

    Science.gov (United States)

    Zhou, Kehua; Ma, Yan; Brogan, Michael S

    2015-12-01

    Although Western medical acupuncture (WMA) is commonly practised in the UK, a particular approach called dry needling (DN) is becoming increasingly popular in other countries. The legitimacy of the use of DN by conventional non-physician healthcare professionals is questioned by acupuncturists. This article describes the ongoing debate over the practice of DN between physical therapists and acupuncturists, with a particular emphasis on the USA. DN and acupuncture share many similarities but may differ in certain aspects. Currently, little information is available from the literature regarding the relationship between the two needling techniques. Through reviewing their origins, theory, and practice, we found that DN and acupuncture overlap in terms of needling technique with solid filiform needles as well as some fundamental theories. Both WMA and DN are based on modern biomedical understandings of the human body, although DN arguably represents only one subcategory of WMA. The increasing volume of research into needling therapy explains its growing popularity in the musculoskeletal field including sports medicine. To resolve the debate over DN practice, we call for the establishment of a regulatory body to accredit DN courses and a formal, comprehensive educational component and training for healthcare professionals who are not physicians or acupuncturists. Because of the close relationship between DN and acupuncture, collaboration rather than dispute between acupuncturists and other healthcare professionals should be encouraged with respect to education, research, and practice for the benefit of patients with musculoskeletal conditions who require needling therapy. PMID:26546163

  20. Dry needling versus acupuncture: the ongoing debate.

    Science.gov (United States)

    Zhou, Kehua; Ma, Yan; Brogan, Michael S

    2015-12-01

    Although Western medical acupuncture (WMA) is commonly practised in the UK, a particular approach called dry needling (DN) is becoming increasingly popular in other countries. The legitimacy of the use of DN by conventional non-physician healthcare professionals is questioned by acupuncturists. This article describes the ongoing debate over the practice of DN between physical therapists and acupuncturists, with a particular emphasis on the USA. DN and acupuncture share many similarities but may differ in certain aspects. Currently, little information is available from the literature regarding the relationship between the two needling techniques. Through reviewing their origins, theory, and practice, we found that DN and acupuncture overlap in terms of needling technique with solid filiform needles as well as some fundamental theories. Both WMA and DN are based on modern biomedical understandings of the human body, although DN arguably represents only one subcategory of WMA. The increasing volume of research into needling therapy explains its growing popularity in the musculoskeletal field including sports medicine. To resolve the debate over DN practice, we call for the establishment of a regulatory body to accredit DN courses and a formal, comprehensive educational component and training for healthcare professionals who are not physicians or acupuncturists. Because of the close relationship between DN and acupuncture, collaboration rather than dispute between acupuncturists and other healthcare professionals should be encouraged with respect to education, research, and practice for the benefit of patients with musculoskeletal conditions who require needling therapy.

  1. Hollow-core tapered coupler for large inner diameter hollow-core optical fibers

    Institute of Scientific and Technical Information of China (English)

    Guiyao Zhou(周桂耀); Zhiyun Hou(侯峙云); Lantian Hou(侯蓝田); Jigang Liu(刘继刚)

    2003-01-01

    A novel hollow-core tapered coupler has been theoretically designed and fabricated by fiber drawing machine. The coupler's inner wall is coated with a polycrystalline GeO2 film. The coupling loss of hollow-core tapered coupler is about 0.2 dB. Hollow-core tapered coupler reduces the transmission loss of hollow-core optical fiber (HCOF) by 0.5 dB/m, therefore the coupler is suitable for coupling high power CO2 laser in industrial application.

  2. Robotic catheter cardiac ablation combining ultrasound guidance and force control

    OpenAIRE

    Kesner, Samuel Benjamin; Howe, Robert D.

    2014-01-01

    Cardiac catheters allow physicians to access the inside of the heart and perform therapeutic interventions without stopping the heart or opening the chest. However, conventional manual and actuated cardiac catheters are currently unable to precisely track and manipulate the intracardiac tissue structures because of the fast tissue motion and potential for applying damaging forces. This paper addresses these challenges by proposing and implementing a robotic catheter system that uses 3D ultras...

  3. Hollow rhodoliths increase Svalbard's shelf biodiversity

    Science.gov (United States)

    Teichert, Sebastian

    2014-11-01

    Rhodoliths are coralline red algal assemblages that commonly occur in marine habitats from the tropics to polar latitudes. They form rigid structures of high-magnesium calcite and have a good fossil record. Here I show that rhodoliths are ecosystem engineers in a high Arctic environment that increase local biodiversity by providing habitat. Gouged by boring mussels, originally solid rhodoliths become hollow ecospheres intensely colonised by benthic organisms. In the examined shelf areas, biodiversity in rhodolith-bearing habitats is significantly greater than in habitats without rhodoliths and hollow rhodoliths yield a greater biodiversity than solid ones. This biodiversity, however, is threatened because hollow rhodoliths take a long time to form and are susceptible to global change and anthropogenic impacts such as trawl net fisheries that can destroy hollow rhodoliths. Rhodoliths and other forms of coralline red algae play a key role in a plurality of environments and need improved management and protection plans.

  4. Use of tunnelled catheters in haematological malignancy patients with neutropenia.

    Science.gov (United States)

    Sariosmanoglu, N; Uğurlu, B; Turgut, N H; Demirkan, F; Ozsan, H; Ergor, G; Gulay, Z; Hazan, E; Oto, O

    2008-01-01

    This prospective study analysed 83 patients (age 45 +/- 17 years) with haematological neoplasms, implanted with 93 tunnelled catheters, who were neutropenic or developed neutropenia during treatment. Catheters were implanted in the right (n = 82) or left (n = 11) jugular vein by the same surgical team using the same technique. They remained in place for 124 +/- 88 days: 29% were removed due to infection; 18% due to treatment termination and 2% due to mechanical problems. Seventeen patients died with catheters in place. At 30, 60, 90, 120 and 200 days mean catheter duration rates were 82%, 75%, 65%, 60% and 35%, respectively, and freedom from catheter removal due to infection was 92%, 88%, 80%, 77% and 67%, respectively. Patient diagnosis and history of previous catheter infection did not increase catheter infection risk, but patients undergoing stem cell transplantation had an increased infection risk. Tunnelled catheters can be used in high-risk patients with neutropenia. Systemic infections can be managed in most patients without catheter removal. PMID:18831907

  5. Encrusted and incarcerated urinary bladder catheter: what are the options?

    Directory of Open Access Journals (Sweden)

    Christopher C.K. Ho

    2010-11-01

    Full Text Available Urinary bladder catheter encrustations are known complications of long-term urinary catheterisation, which is commonly seen in clinical practice. These encrustations can impede deflation of the balloon and therefore cause problems in the removal of the catheter. The options in managing an encrusted and incarcerated urinary bladder catheter include extracorporeal shock wave lithotripsy and lithoclast. We describe here another technique of dealing with a stuck and encrustated catheter, via direct crushing of the encrustations with a rigid cystoscope inserted through a suprapubic cystostomy tract.

  6. Real-time multipoint gastrointestinal 19-fluorine catheter tracking

    OpenAIRE

    Hahn, Tobias; Kozerke, Sebastian; Schwizer, Werner; Fried, Michael; Boesiger, Peter; Steingoetter, Andreas

    2014-01-01

    PURPOSE: To develop MR based real-time gastrointestinal 19-Fluorine (19F) catheter tracking and visualization allowing for real-time detection and feedback of 3D catheter shape and movement as well as catheter-driven adjustments of 1H imaging geometry parameters. METHODS: Data were acquired on a 3T clinical system using 3D Golden Angle radial sampling. Two gastrointestinal catheters incorporating four fiducial 19F markers (65 or 50 µL marker volume) were tracked while being pulled through ...

  7. Vibration Analysis of Hollow Tapered Shaft Rotor

    OpenAIRE

    P. M. G. Bashir Asdaque; Behera, R. K.

    2014-01-01

    Shafts or circular cross-section beams are important parts of rotating systems and their geometries play important role in rotor dynamics. Hollow tapered shaft rotors with uniform thickness and uniform bore are considered. Critical speeds or whirling frequency conditions are computed using transfer matrix method and then the results were compared using finite element method. For particular shaft lengths and rotating speeds, response of the hollow tapered shaft-rotor system is determined for t...

  8. BOX-DEATH HOLLOW ROADLESS AREA, UTAH.

    Science.gov (United States)

    Weir, Gordon W.; Lane, Michael

    1984-01-01

    Geologic mapping, geochemical sampling, and a search for prospects and mineralized rock in the Box-Death Hollow Roadless Area, Utah indicate that there is little promise for the occurrence of mineral or energy resources in the area. Additional exploratory drilling by industry seems warranted if wells elsewhere in the region find oil or gas in strata as yet untested in the Box-Death Hollow Roadless Area.

  9. Mode characteristics of hollow core Bragg fiber

    Institute of Scientific and Technical Information of China (English)

    Minning Ji; Zhidong Shi; Qiang Guo

    2005-01-01

    Analytical expression to calculate propagation constant and mode field of the hollow core Bragg fiber is derived. Numerical results are presented. It is shown that the fundamental mode of the hollow core Bragg fiber is circularly symmetric TE01 mode with no polarization degeneracy, while the higher order mode may be HE11, TM01, or TE02 etc.. This property is different from conventional optical fiber that its fundamental mode is the linearly polarized HE11 mode and is polarization degeneracy.

  10. Malignant pleural effusion in the presence of trapped lung. Five-year experience of PleurX tunnelled catheters.

    Science.gov (United States)

    Efthymiou, Christopher Andrew; Masudi, Tahir; Thorpe, James Andrew Charles; Papagiannopoulos, Kostas

    2009-12-01

    Malignant pleural effusions in the presence of trapped lung remain notoriously difficult to treat. Various methods exist ranging from minimally invasive procedures including repeated needle thoracocentesis to the need for a formal surgical procedure such as placement of a pleuroperitoneal shunt and even thoracotomy and decortication. Controversy exists as to what is the optimum treatment for this condition. Any planned treatment should balance the therapeutic benefit provided against convalesce for a disease with a limited life expectancy. Patients should not spend a significant proportion of their remaining life span recovering from palliative procedures. In a series of patients with malignant pleural effusion the medial survival time was 20 weeks, with 30 days and 1 year mortality rates of 12.8% and 83.6%, respectively. We describe our five-year experience with the use of indwelling PleurX catheters in patients with malignant pleural effusions in the presence of confirmed trapped lung on radiological or VATS investigation. Patient health related quality of life was investigated by telephone questionnaire. The parameters analysed were symptomatic relief, mobility and ease of management following insertion. One hundred and sixteen patients underwent PleurX catheter insertion by a single operator, 48 questionnaires were completed. Of the 48 cases analysed, improvement in all three quality of life indices was recorded following catheter insertion. Ease of mobility was recorded as moderately satisfied and very satisfied in 50% and 15% of patients, respectively. Symptomatic improvement was found to have been increased with 42% and 6% of patients responding to moderately satisfied and very satisfied, respectively. Ease of management was recorded as 'slightly satisfied' and moderately satisfied in 50% and 33% of patients, respectively, demonstrating a high satisfaction index in patients with chronic progressively debilitating malignancies. Complications were either

  11. Methods for segmenting curved needles in ultrasound images.

    Science.gov (United States)

    Okazawa, Stephen H; Ebrahimi, Richelle; Chuang, Jason; Rohling, Robert N; Salcudean, Septimiu E

    2006-06-01

    Ultrasound-guided percutaneous needle insertions are widely used techniques in current clinical practice. Some of these procedures have a high degree of difficulty because of poor observability of the needle in the ultrasound image. There have been recent efforts to improve guidance by computer assisted needle detection. These software techniques are often limited by not representing needle curvature. We present two methods to detect the needle in 2D ultrasound that specifically address needle curvature. Firstly, we demonstrate a real-time needle segmentation algorithm based on the Hough transform which detects the needle and represents its curved shape. Secondly, we demonstrate how a new coordinate transformation can transform detection of a curved needle to a linear fit. These methods are demonstrated on ultrasound and photographic images.

  12. Percutaneous needle aspiration biopsy of chest lesions: effectiveness when using an 18-gauge needle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Min; Jung, Gyoo Sik; Kim, So Sun; Huh, Jin Do; Joh, Young Duk; Huh, Bang [College of Medicine, Kosin National University, Busan (Korea, Republic of)

    1995-01-15

    Results of 181 percutaneous needle aspiration biopsies performed with an 18-gauge needle during a period of 3 years were analyzed to determine efficacy and safety of the procedure. Biposies were performed in patients that could not be diagnosed by bronchoscopy or sputum cytology. The biopsy procedure with 18-gauge Crown needle was guided by fluoroscopy. The biopsy specimen placed in 10% formalin solution were histologically confirmed. In 160 patients (89%), the positive diagnosis was made by percutaneous needle aspiration biopsy. There were 153 lung lesions (120 malignant and 33 benign lesions) and 7 mediastinal lesions. The diagnostic accuracy of malignant and benign disease was 91% and 80% respectively. Complications included pneumothorax (n = 11) and hemothorax (n = 1): six of them required treatment with chest tube and the remainder showed spontaneous resorption. PCNB with an 18-gauge needle provided a reliable, relatively safe diagnostic tool to establish the diagnosis of both malignant and benign chest lesions.

  13. Percutaneous needle aspiration biopsy of chest lesions: effectiveness when using an 18-gauge needle

    International Nuclear Information System (INIS)

    Results of 181 percutaneous needle aspiration biopsies performed with an 18-gauge needle during a period of 3 years were analyzed to determine efficacy and safety of the procedure. Biposies were performed in patients that could not be diagnosed by bronchoscopy or sputum cytology. The biopsy procedure with 18-gauge Crown needle was guided by fluoroscopy. The biopsy specimen placed in 10% formalin solution were histologically confirmed. In 160 patients (89%), the positive diagnosis was made by percutaneous needle aspiration biopsy. There were 153 lung lesions (120 malignant and 33 benign lesions) and 7 mediastinal lesions. The diagnostic accuracy of malignant and benign disease was 91% and 80% respectively. Complications included pneumothorax (n = 11) and hemothorax (n = 1): six of them required treatment with chest tube and the remainder showed spontaneous resorption. PCNB with an 18-gauge needle provided a reliable, relatively safe diagnostic tool to establish the diagnosis of both malignant and benign chest lesions

  14. Evaluation of a novel Seldinger-needle for computed tomography guided interventions: initial experiences; Evaluierung einer neuen Seldinger-Nadel fuer computertomografisch gesteuerte Interventionen: Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Plumhans, C.; Mahnken, A.; Iwa, R.; Behrendt, F.F.; Sebastian, K.; Guenther, R.W.; Honnef, D. [Universitaetsklinikum RWTH Aachen (Germany). Klinik fuer Radiologische Diagnostik

    2009-02-15

    To evaluate a new Seldinger puncture device for computed tomography-guided interventions under difficult conditions, to analyze applicability, and to investigate assets and drawbacks. From November 2007 to March 2008, we performed CT-guided interventions in 16 patients (7 women, 9 men; mean age 62 years old) using a new 20G-Seldinger needle (Sika-Med, Wiehl, Germany). This novel needle serves as a guide for many different interventional devices due to a guide wire welded on the proximal needle end. It allows continuous application of anesthesia via four tiny holes at the distal needle end until the region of interest is reached. Each intervention was subject to difficult interventional conditions. The indications for intervention were drainage (n = 7), Trucut biopsy of tumor (n = 8) and radiofrequency ablation (n = 1). Handling, success, advantages, drawbacks, complications and patient tolerance were noted after each procedure. A pain scale from 1 - 10 was used to grade the pain level during the intervention. All interventions were performed successfully and no severe complications were observed. Patient tolerance was very good resulting in a mean pain score of 2 {+-} 1. Regions with dangerous and difficult access were successfully reached with the new Seldinger needle in 15 of 16 cases by dilatation of the puncture tract and continuous administration of local anesthesia via the system. Furthermore, different devices such as Trucut systems and a drainage catheter were able to be inserted without complication via the needle. With a proximal removable luer-lock connection, liquid material was able to be aspirated in six cases. Under difficult interventional conditions, the use of a Seldinger needle as a reliable technique for CT-guided interventions can provide a safe and successful procedure. (orig.)

  15. DIY guide-needle-assisted conjunctivodacryocystorhinostomy (CDCR).

    Science.gov (United States)

    Paik, Ji-Sun; Kim, Su-Ah; Doh, Sang-Hee

    2013-01-01

    In this study, we introduce DIY guide-needle-assisted conjunctivodacryocystorhinostomy (CDCR), in which a guide needle helps in measuring the initial Jones tube length for insertion and reduces unnecessary handling for tube changes. Three CDCR procedures were conducted in which the length of the Jones tube was calculated using a 22-gauge DIY guide needle, and a prospective study of tube position change and migration, (a major cause of CDCR failure) was done. Wound healing was almost complete within 4 weeks postoperatively in the osteotomy site, but in cases of partial middle turbinectomy, a little more time was necessary. There was a slight change in Jones tube position in the nasal cavity compared with the expected position of original tube tip, but no tube migration from the caruncle fixation position had occurred by the final follow-up time. This guide-needle-assisted CDCR has multiple advantages, such as easy measurement of the proper initial tube size, utilization of the initial needle path, and easy replacement of tubes. Finally, this approach to CDCR can be readily applied because it uses materials ordinarily found in hospitals to create the devices needed for the procedure, so there is no additional cost. PMID:22526574

  16. Medically relevant ElectroNeedle technology development.

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Carrie Frances; Thomas, Michael Loren; McClain, Jaime L.; Harper, Jason C.; Achyuthan, Komandoor E.; Ten Eyck, Gregory A.

    2008-11-01

    ElectroNeedles technology was developed as part of an earlier Grand Challenge effort on Bio-Micro Fuel Cell project. During this earlier work, the fabrication of the ElectroNeedles was accomplished along with proof-of-concept work on several electrochemically active analytes such as glucose, quinone and ferricyanide. Additionally, earlier work demonstrated technology potential in the field of immunosensors by specifically detecting Troponin, a cardiac biomarker. The current work focused upon fabrication process reproducibility of the ElectroNeedles and then using the devices to sensitively detect p-cresol, a biomarker for kidney failure or nephrotoxicity. Valuable lessons were learned regarding fabrication assurance and quality. The detection of p-cresol was accomplished by electrochemistry as well as using fluorescence to benchmark ElectroNeedles performance. Results from these studies will serve as a guide for the future fabrication processes involving ElectroNeedles as well as provide the groundwork necessary to expand technology applications. One paper has been accepted for publication acknowledging LDRD funding (K. E. Achyuthan et al, Comb. Chem. & HTS, 2008). We are exploring the scope for a second paper describing the applications potential of this technology.

  17. Temperature-controlled irrigated tip radiofrequency catheter ablation: comparison of in vivo and in vitro lesion dimensions for standard catheter and irrigated tip catheter with minimal infusion rate

    DEFF Research Database (Denmark)

    Petersen, H H; Chen, X; Pietersen, A;

    1998-01-01

    In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures <60% partly due to the limited lesion size after conventional radiofrequency ablation. Irrigated tip radiofrequency ablation using power control and high infusion rates enlarges lesion size, but has...... increased risk of cratering. The present study explores irrigated tip catheter ablation in temperature-controlled mode, target temperature 60 degrees C, using an irrigation rate of 1 mL/min, comparing this to conventional catheter technique, target temperature 80 degrees C....

  18. Hollow glass for insulating layers

    Science.gov (United States)

    Merticaru, Andreea R.; Moagar-Poladian, Gabriel

    1999-03-01

    Common porous materials, some of which will be considered in the chapters of this book, include concrete, paper, ceramics, clays, porous semiconductors, chromotography materials, and natural materials like coral, bone, sponges, rocks and shells. Porous materials can also be reactive, such as in charcoal gasification, acid rock dissolution, catalyst deactivation and concrete. This study continues the investigations about the properties of, so-called, hollow glass. In this paper is presented a computer simulation approach in which the thermo-mechanical behavior of a 3D microstructure is directly computed. In this paper a computer modeling approach of porous glass is presented. One way to test the accuracy of the reconstructed microstructures is to computed their physical properties and compare to experimental measurement on equivalent systems. In this view, we imagine a new type of porous type of glass designed as buffer layer in multilayered printed boards in ICs. Our glass is a variable material with a variable pore size and surface area. The porosity could be tailored early from the deposition phases that permitting us to keep in a reasonable balance the dielectric constant and thermal conductivity.

  19. Duration and Adverse Events of Non-cuffed Catheter in Patients With Hemodialysis

    Science.gov (United States)

    2014-10-09

    Renal Failure Chronic Requiring Hemodialysis; Central Venous Catheterization; Inadequate Hemodialysis Blood Flow; Venous Stenosis; Venous Thrombosis; Infection Due to Central Venous Catheter; Central Venous Catheter Thrombosis

  20. Comparison of Standard Catheters Versus Radial Artery-Specific Catheter in Patients Who Underwent Coronary Angiography Through Transradial Access.

    Science.gov (United States)

    Chen, On; Goel, Sunny; Acholonu, Michael; Kulbak, Guy; Verma, Shivani; Travlos, Efstratios; Casazza, Richard; Borgen, Elliot; Malik, Bilal; Friedman, Michael; Moskovits, Norbert; Frankel, Robert; Shani, Jacob; Ayzenberg, Sergey

    2016-08-01

    In this prospective, randomized controlled study, we aim to compare the performance outcomes of standard catheters with the radial artery-specific catheter. Over the past decade, transradial cardiac catheterization has gained widespread popularity because of its low complication rates compared with transfemoral access. Operators have the choice of using either standard catheters (used for both transfemoral and transradial approach, with need for separate catheter use for either right or left coronary artery engagement) or a dedicated radial artery catheter, which is specifically designed to engage both coronary arteries through radial artery access. A total of 110 consecutive patients who underwent coronary angiography at our institution from March 2015 to April 2015 were prospectively randomized to either radial artery-specific Tiger catheter (5Fr; Terumo Interventional Systems, Somerset, New Jersey) versus standard Judkins left and right catheters (5Fr R4, L4; Cordis Corporation, Miami, Florida). The end points of the study included fluoroscopy time, dose-area product, contrast volume used, and total procedure time for the coronary angiography. A total of 57 patients (52%) were randomized to radial artery-specific catheter and 53 (48%) to the standard catheter. Tiger catheter was associated with significantly lower fluoroscopy time (184 ± 91 vs 238 ± 131 seconds, p = 0.015), which was statistically significant. Other outcome measures such as dose-area product (2,882.4 ± 1,471.2 vs 3,524.6 ± 2,111.7 Gy·cm(2), p = 0.07), total contrast volume (48.1 ± 16.1 vs 53.4 ± 18.5 ml, p = 0.114), and total procedure time (337 ± 382 vs 434 ± 137 seconds, p = 0.085) were also lower in single-catheter group, but it did not reach statistical significance. A total of 8 patients (14%) were crossed over from radial-specific catheter arm to standard catheter arm because of substandard image quality and difficulty in coronary engagement. Six patients had to be

  1. Central venous access for haemodialysis using the Hickman catheter.

    Science.gov (United States)

    Cappello, M; De Pauw, L; Bastin, G; Prospert, F; Delcour, C; Thaysse, C; Dhaene, M; Vanherweghem, J L; Kinnaert, P

    1989-01-01

    One hundred and seven Hickman catheters for haemodialysis were inserted in 90 end-stage chronic renal failure patients, and were used for 1-448 days (median 45 days). Sixty-nine per cent of the patients were treated without any problem for 1-165 days (median 34 days). Clinically evident complications occurred in 44 catheters inserted in 28 patients, and included outflow obstruction (16.8% of the catheters) and thrombosis (13.1% of the catheters). However, many episodes of clotting or insufficient flow could be corrected by simple manoeuvres. Other less frequent complications were recorded: sepsis, mainly in patients with increased risk factors (4.1% of the catheters), laceration of the catheter (3.7%) and occasional cases of jugular-vein phlebitis, transient palsy of a vocal cord, haematoma of the wound, and bleeding of the cutaneous orifice. No clinical sign of subclavian or innominate-vein thrombosis was observed. Nevertheless, a prospective study conducted in 50 asymptomatic patients demonstrated a 12% rate of anomalies of the venous system, although two-thirds of these alterations were mild and had no consequence. When the present series is compared to the results obtained with currently available percutaneous haemodialysis catheters, it is concluded that the Hickman catheter is a safe, comfortable and efficient vascular access device. PMID:2516892

  2. Engineering Considerations Of Catheters For Intravascular Ultrasonic Measurements

    Science.gov (United States)

    Martin, Roy W.; Johnson, Christopher C.

    1989-08-01

    The mechanical properties of commonly used fluid transfusion or pressure monitoring catheters are similar to the properties required of catheters which include sensing devices. Consequently, bending and torsional stiffness of commercial catheters and tubes were measured at both room and body temperature. Five of these usually placed with the aid of fluoroscopy had an average Young's modulus of 5714x101 dyne/cm at 21°C which decreased 29% at body temperature; a shear modulus of 70.5x101 dyne/cm 4 at 21°C which decreased 13% at body temperature, and plastic deformation of 8% when loaded for 1 minute at 37°. Four of these were composed of a composite material. Catheters which are balloon directed during insertion had moduli values approximately 1/3 of these or less. The drag forces produced on balloons used on such catheters were measured for fluid velocities ranging from 10-50 cm/sec. Using this information the average force applied to a balloon throughout a cardiac cycle was calculated; values of 1280 dynes for a .6 ml balloon and 2490 dynes for a 1 ml balloon were found. The maximum wall thicknesses to catheter radii for single lumen catheters were determined for various material moduli which would allow the catheter tip to be directed by a balloon during its passage into the right heart.

  3. 21 CFR 870.1350 - Catheter balloon repair kit.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Catheter balloon repair kit. 870.1350 Section 870... repair kit. (a) Identification. A catheter balloon repair kit is a device used to repair or replace the... effect the repair or replacement. (b) Classification. Class III (premarket approval). (c) Date PMA...

  4. Dose requirements for UVC disinfection of catheter biofilms

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D.; Tvede, Michael;

    2009-01-01

    Bacterial biofilms on permanent catheters are the major sources of infection. Exposure to ultraviolet-C (UVC) light has been proposed as a method for disinfecting the inner surface of catheters. Specification of a UVC-based device for in vivo disinfection is based on the knowledge of the required...

  5. Safety and efficacy of catheter-directed thrombolysis

    DEFF Research Database (Denmark)

    Bækgaard, N; Klitfod, Lotte; Broholm, R

    2012-01-01

    To describe the background for--and mechanism of--catheter-directed thrombolysis (CDT) for iliofemoral deep venous thrombosis (DVT) accessed via the popliteal vein. Focus is on safety and efficacy.......To describe the background for--and mechanism of--catheter-directed thrombolysis (CDT) for iliofemoral deep venous thrombosis (DVT) accessed via the popliteal vein. Focus is on safety and efficacy....

  6. A new method to repair the ruptured silicone PICC catheter%硅胶材质 PICC 导管破损的修复新方法

    Institute of Scientific and Technical Information of China (English)

    喻燕敏; 徐思思; 姚伟荣

    2014-01-01

    目的:探讨新型方法修复断裂的BD PICC导管。方法:选择导管破损患者2例,导管送管困难患者3例,在无菌操作下,将断裂的原导管轻轻向外拖移3 cm,用无菌剪刀将破裂导管尾部剪去,先将巴德导管末端连接器的减压套筒穿过留在体外的导管,然后再将导管与针芯柄对扣锁住。结果:2例导管破损患者使用该方法成功修复,在后续使用中均未出现漏液、脱落、堵管、感染。2例使用时间超过210 d,现仍在带管中。3例因送管困难患者中,1例留置216 d,后因死亡拔管;2例留置30 d拔管。结论:该种修复方法安全有效,值得临床推广应用。%Explored a new method to repair the ruptured BD silicone PICC catheter .Methods:The ruptured catheter was pulled gently outward 3 cm and the tail of ruptured catheter was cut off .Then the end connection device of Bard PICC catheter was moved through the ruptured catheter staying out-side of the body.The catheter and the core needle were jointed and the repairment was finished .Results:Two ruptured silicone PICC catheters were repaired successfully using this method and no leakage,separation,plugging and infection was observed in the subsequent use,they had used the repaired catheters more than 210 days.1 patient used 216 days and 2 patients used 30 days amang 3 patients with difficulty sending pipe .Conclusion:The repairing method mentioned in this paper was safe and useful.It is worth to be promoted.

  7. TREATMENT OF EPIGASTRIC PAIN WITH SUBCUTANEOUS NEEDLING

    Institute of Scientific and Technical Information of China (English)

    GUO Jia-tu

    2006-01-01

    @@ Subcutaneous needling is a new therapeutic method which is based on the features of the meridian-collateral theory of cutaneous regions in traditional Chinese medicine and the neurohumeral theory and skin anatomy of modern medicine and is of the features of "fixed meridian but not fixed acupoints", "micro stimulation", and "subcutaneous needling with filiform needles" to achieve the goal of treating diseases. This method is indicated clinically to the analgesia and relaxation of spasm especially the pain caused by the disorders of the internal organs and marked therapeutic effect has been obtained. With method, 150 cases of epigastric pain were treated by our department and the total effective rate was over 90%. It is presented herein below.

  8. Monitoring Atrial Fibrillation After Catheter Ablation

    Directory of Open Access Journals (Sweden)

    Giovanni B Forleo, MD PhD; MAssimo Moltrasio, MD; Michela Casella MD, PhD; Antonio Dello Russo MD, PhD; Getano Fassini, MD; Manfredi Tesauro, MD, PhD; Claudio Tondo, MD, PhD.

    2014-04-01

    Full Text Available Although catheter ablation is an effective treatment for recurrent atrial fibrillation (AF, there is no consensus on the definition of success or follow-up strategies. Symptoms are the major motivation for undergoing catheter ablation in patients with AF, however it is well known that reliance on perception of AF by patients after AF ablation results in an underestimation of recurrence of the arrhythmia. Because symptoms of AF occurrence may be misleading, a reliable assessment of rhythm outcome is essential for the definition of success in both clinical care and research trials. Continuous rhythm monitoring over long periods of time is superior to intermittent recording using external monitors to detect the presence of AF episodes and to quantify the AF burden. Today, new devices implanted subcutaneously using a minimally invasive technique have been developed for continuous AF monitoring. Implantable devices keep detailed information about arrhythmia recurrences and might allow identification of very brief episodes of AF, the significance of which is still uncertain. In particular, it is not known whether there is any critical value of daily AF burden that has a prognostic significance. This issue remains an area of active discussion, debate and investigation. Further investigation is required to determine if continuous AF monitoring with implantable devices is effective in reducing stroke risk and facilitating maintenance of sinus rhythm after AF ablation.

  9. Needle-Stick Injury among Health Care Workers in Hemodialysis Units in Nigeria: A Multi-Center Study

    Directory of Open Access Journals (Sweden)

    CO Amira

    2014-01-01

    Full Text Available Background: Needle-stick and sharps injuries carry the risk of infection and are occupational hazards for all health care professionals involved in clinical care.Objective: To determine the frequency and factors contributing to needle-stick injury (NSI among health care workers of dialysis units in Lagos, Nigeria.Methods: Data were obtained by anonymous, self-reporting questionnaire from staff of 4 hemodialysis units between October and December 2011. Information on demographics, job category and duration, details of NSI in the past, kind of activity and procedure under which the NSI occurred, if injury was reported, vaccination status of staff, and post-exposure treatment received were obtained.Results: The study population included 38 (37.3% doctors, 42 nurses (41.2%, 14 (13.7% dialysis technicians and 8 (7.8% ancillary staff. There were 39 (38.2% males. The mean±SD age of the study population was 34.4±8.3 years. 25 (24.5% staff had suffered NSI in the last 12 months and 41 (40.2% in their entire working career. The most common activity leading to NSI was recapping of needles (45%, improper disposal of needles (30%, and venous cannulation and setting of drips (27.5%. NSI was significantly (p=0.016 higher among those with work experience between 6 and 10 years than others. Hollow bore needles were responsible for 82.9% of the NSIs. Only 15 (37% respondents reported their NSI to their unit head or designated officer in order to get medical advice.Conclusion: In Lagos, Nigeria, NSI is common among hemodialysis staff and is under-reported. Many NSIs can be prevented by adhering to the practice of universal precautions as well as education of staff on such precautionary methods.

  10. Determination of the Stoichiometry of the Complete Bacterial Type III Secretion Needle Complex Using a Combined Quantitative Proteomic Approach.

    Science.gov (United States)

    Zilkenat, Susann; Franz-Wachtel, Mirita; Stierhof, York-Dieter; Galán, Jorge E; Macek, Boris; Wagner, Samuel

    2016-05-01

    Precisely knowing the stoichiometry of their components is critical for investigating structure, assembly, and function of macromolecular machines. This has remained a technical challenge in particular for large, hydrophobic membrane-spanning protein complexes. Here, we determined the stoichiometry of a type III secretion system of Salmonella enterica serovar Typhimurium using two complementary protocols of gentle complex purification combined with peptide concatenated standard and synthetic stable isotope-labeled peptide-based mass spectrometry. Bacterial type III secretion systems are cell envelope-spanning effector protein-delivery machines essential for colonization and survival of many Gram-negative pathogens and symbionts. The membrane-embedded core unit of these secretion systems, termed the needle complex, is composed of a base that anchors the machinery to the inner and outer membranes, a hollow filament formed by inner rod and needle subunits that serves as conduit for substrate proteins, and a membrane-embedded export apparatus facilitating substrate translocation. Structural analyses have revealed the stoichiometry of the components of the base, but the stoichiometry of the essential hydrophobic export apparatus components and of the inner rod protein remain unknown. Here, we provide evidence that the export apparatus of type III secretion systems contains five SpaP, one SpaQ, one SpaR, and one SpaS. We confirmed that the previously suggested stoichiometry of nine InvA is valid for assembled needle complexes and describe a loose association of InvA with other needle complex components that may reflect its function. Furthermore, we present evidence that not more than six PrgJ form the inner rod of the needle complex. Providing this structural information will facilitate efforts to obtain an atomic view of type III secretion systems and foster our understanding of the function of these and related flagellar machines. Given that other virulence

  11. Preparation of hollow spherical carbon nanocages

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, C.-K.; Kang, H. Y.; Hong, C.-I; Huang, C.-H.; Chang, F.-C.; Wang, H. Paul, E-mail: wanghp@mail.ncku.edu.tw [National Cheng Kung University, Department of Environmental Engineering, Taiwan (China)

    2012-12-15

    This study presents a new and simple method for the synthesis of hollow carbon spheres possessing nanocage sizes of 7.1, 14, and 20 nm in diameter. The core-shell (i.e., Cu-C) nanoparticles prepared by carbonization of the Cu{sup 2+}-cyclodextrin (CD) complexes at 573 K for 2 h was etched with HCl (6N) to yield the hollow carbon spheres. The carbon-shell of the hollow carbon nanospheres, which consisted of mainly diamond-like and graphite carbons, is not perturbed during etching. In addition to the nanocages, the hollow carbon nanospheres also possess micropores with an opening of 0.45 nm, allowing small molecules to diffuse in and out through the carbon-shell. Many elements (such as Zn{sup 2+} or Cu{sup 2+}) can therefore be filled into the nanocages of the hollow carbon nanospheres. With these unique properties, for instance, designable active species such as Cu and ZnO encapsulated in the carbon-shell can act as Cu-ZnO-C yolk-shell nanoreactors which are found very effective in the catalytic decomposition of methanol.

  12. Urethral catheter insertion forces: a comparison of experience and training

    Directory of Open Access Journals (Sweden)

    Benjamin K. Canales

    2009-02-01

    Full Text Available Purpose: This study was undertaken to evaluate the insertion forces utilized during simulated placement of a urethral catheter by healthcare individuals with a variety of catheter experience. Materials and Methods: A 21F urethral catheter was mounted to a metal spring. Participants were asked to press the tubing spring against a force gauge and stop when they met a level of resistance that would typically make them terminate a catheter placement. Simulated catheter insertion was repeated fives times, and peak compression forces were recorded. Healthcare professionals were divided into six groups according to their title: urology staff, non-urology staff, urology resident/ fellow, non-urology resident/ fellow, medical student, and registered nurse. Results: A total of fifty-seven healthcare professionals participated in the study. Urology staff (n = 6 had the lowest average insertion force for any group at 6.8 ± 2.0 Newtons (N. Medical students (n = 10 had the least amount of experience (1 ± 0 years and the highest average insertion force range of 10.1 ± 3.7 N. Health care workers with greater than 25 years experience used significantly less force during catheter insertions (4.9 ± 1.8 N compared to all groups (p < 0.01. Conclusions: We propose the maximum force that should be utilized during urethral catheter insertion is 5 Newtons. This force deserves validation in a larger population and should be considered when designing urethral catheters or creating catheter simulators. Understanding urethral catheter insertion forces may also aid in establishing competency parameters for health care professionals in training.

  13. Feasibility and outcome of proximal catheter ileostomy - A pilot study

    Directory of Open Access Journals (Sweden)

    Maulana M Ansari

    2011-01-01

    Full Text Available Background/Aim: Loop ileostomy has high complication rates and causes much patient inconvenience. This study was carried out to evaluate the feasibility and outcome of a proximal catheter ileostomy in place of loop ileostomy in patients treated by intestinal repair and/or resection-anastomosis. Design: Prospective study. Setting: J. N. Medical College Hospital, Aligarh Muslim University, Aligarh, India. Patients and Methods: From November 2006 to November 2009, in all patients treated surgically by primary repair and/or resection-anastomosis of small and/or large bowel, we constructed a catheter ileostomy when a defunctioning proximal protective loop ileostomy was considered advisable. Catheter ileostomy was constructed in the fashion of catheter jejunostomy, with postoperative saline irrigation. Results: Catheter ileostomy was performed in 20 patients in the 3-year period. The mean age of the subjects was 28.6 years and the male: female ratio was 1.86:1. Four patients died of septicemia and multiple organ failure unrelated to catheter ileostomy in the immediate postoperative period. Catheter ileostomy started functioning within 48 hours of the operation, and twice-daily irrigation was found sufficient in 81.25% of the surviving patients. Only one patient developed peritubal leak with mild skin excoriation that cleared within 5 days. Another patient with Koch′s abdomen underwent conversion to loop colostomy on re-exploration for postoperative adhesive obstruction. There was no instance of intestinal leak. Ileostomy wounds closed spontaneously within 7-14 days of catheter removal, and none required formal closure. Hospital stay ranged from 12-35 days (mean: 23 days. Conclusions: Catheter ileostomy is effective in protecting intestinal anastomosis/repair; there is minimal morbidity and no catheter-related leak/mortality, and we recommend the procedure.

  14. Efficacy of preventing hemodialysis catheter infections with citrate lock.

    Science.gov (United States)

    Silva, Jorge; Antunes, Jorge; Carvalho, Telmo; Ponce, Pedro

    2012-10-01

    Prevalent use of tunneled dialysis catheters can reach 30%. Infection remains the most serious catheter-related problem. Catheter locks are increasingly used for prevention, but are not yet recommended either by the Food and Drug Association or European Medicines Agency, on the basis of increasing bacterial resistance or lock toxicity. The aim was to test safety and effectiveness of citrate. A prospective, interventional study was conducted to assess the safety and efficacy of a 30% citrate lock in preventing catheter-related bacteremia (CRB). A total of 157 prevalent tunneled catheters were locked with citrate and prospectively followed during a 1-year period. The primary endpoint was first CRB diagnosed according to two of the diagnostic criteria for Catheter Infection of Centers for Disease Control and Prevention (CDC), namely definite and probable infection. The CDC criterion of possible but not proved infection was not considered. This citrate lock cohort (n = 157) had 10 episodes of CRB. We observed 0.49 CRB episodes/1000 patient-days and the mean infection-free catheter day was 130.6 ± 100.9. No clinically relevant adverse events were observed. No proved tunnel or exit site infection was observed and no patients died because of CRB. Catheter obstruction episodes were reported on 69 occasions out of 14 catheters. These results were compared with an historical cohort from a previous study of catheter locking with low-dose gentamicin and did not show significant difference in efficacy. Citrate lock is effective in preventing CRB. No toxicity was observed. The use of citrate lock may have advantages over antibiotic locks: no reported bacterial resistance, lower industrial cost, and less manipulation. PMID:22515732

  15. The Needling Technique and Clinical Application of Point Zhibian

    Institute of Scientific and Technical Information of China (English)

    张远东

    2004-01-01

    @@ The Needling Technique The patient is asked to lie in a lateral or prone position. A No. 28 filiform needle of 3 cun is inserted perpendicularly into the point Zhibian (BL 54), with the direction of the needle tip varying according to the different conditions of the diseases. The needle can be directed in three directions, the first along the sciatic nerve; the second pointing to the genitals; and the third pointing to the anus. The reinforcing,reducing, or even needling manipulation can be used,and the needling depth can be deep or superficial.The needling can also be applied in combination with the warm-needle, cupping, and point-injection.

  16. Method for the production of fabricated hollow microspheroids

    Energy Technology Data Exchange (ETDEWEB)

    Wickramanayake, Shan; Luebke, David R.

    2015-06-09

    The method relates to the fabrication of a polymer microspheres comprised of an asymmetric layer surrounding a hollow interior. The fabricated hollow microsphere is generated from a nascent hollow microsphere comprised of an inner core of core fluid surrounded by a dope layer of polymer dope, where the thickness of the dope layer is at least 10% and less than 50% of the diameter of the inner core. The nascent hollow microsphere is exposed to a gaseous environment, generating a vitrified hollow microsphere, which is subsequently immersed in a coagulation bath. Solvent exchange produces a fabricated hollow microsphere comprised of a densified outer skin surrounding a macroporous inner layer, which surrounds a hollow interior. In an embodiment, the polymer is a polyimide or a polyamide-imide, and the non-solvent in the core fluid and the coagulation bath is water. The fabricated hollow microspheres are particularly suited as solvent supports for gas separation processes.

  17. A double-blind placebo needle for acupuncture research

    Directory of Open Access Journals (Sweden)

    Takakura Nobuari

    2007-10-01

    Full Text Available Abstract Background Placebo needles that can mask acupuncture practitioners to the type of needle used have been considered almost impossible to develop until now. Methods We designed a double-blind non-penetrating placebo needle, the needle tip of which simply presses against the skin, and a matched penetrating needle. The needles are encased inside an opaque guide tube and the appearance and feel of the pair are designed to be indistinguishable. To validate the masking effect for the practitioner, 10 acupuncturists each applied 23 non-penetrating needles and 17 penetrating needles to the Large Intestine-4 point. After removing each needle, they judged whether the needle was 'penetrating', 'non-penetrating' or 'unidentifiable'. For the validation of patient masking, an acupuncturist randomly applied a non-penetrating/penetrating needle pair to the bilateral Sanjiao-5 points in 60 volunteers. When both applications were completed, we asked them to write down anything that they noticed regarding the needle application and associated sensations. Results The mean ± SD of correct/unidentifiable/incorrect answers given by the 10 acupuncturists were 17.0 ± 4.1/6.4 ± 3.6/16.6 ± 3.0, respectively. Regarding patient masking, none of the subjects commented in the questionnaire that they had received a non-penetrating needle. Of 60 penetrating and 60 non-penetrating needle applications, 48 (80.0% and 25 (41.7% applications elicited skin penetration sensation and 48 (80.0% and 20 (33.3% applications elicited de qi, respectively. Conclusion These needles have the potential to mask both practitioners and patients from the type of needle used in acupuncture research.

  18. A computational modeling study on the helium atmospheric pressure plasma needle discharge

    Science.gov (United States)

    Qian, Mu-Yang; Yang, Cong-Ying; Liu, San-Qiu; Wang, Zhen-Dong; Lv, Yan; Wang, De-Zhen

    2015-12-01

    A two-dimensional coupled model of neutral gas flow and plasma dynamics is employed to investigate the streamer dynamics in a helium plasma needle at atmospheric pressure. A parametric study of the streamer propagation as a function of needle tip curvature radius and helium gas flow rate is presented. The key chemical reactions at the He/air mixing layer which drive the streamer propagation are the direct ionization via collision with electrons, the Penning effect being not so crucial. With increasing the gas flow rate from 0.2 standard liter per minute (SLM) to 0.8 SLM, however, the emissions resulting from reactive oxygen and nitrogen species change from a solid circle to a hollow profile and the average streamer propagation velocity decreases. Air impurities (backdiffusion from ambient air) in the helium jet result in a significant increase in the streamer propagation velocity. Besides, with decreasing the tip curvature radiusfrom 200 μm to 100 μm, the electron avalanche process around the near-tip region is more pronounced. However, the spatially resolved plasma parameters distributions (electron, helium metastables, ground state atomic oxygen, etc.) remain almost the same, except that around the near-tip region where their peak values are more than doubled. Project supported partly by the National Natural Science Foundation of China (Grant No. 11465013), the Natural Science Foundation of Jiangxi Province, China (Grant No. 20151BAB212012), and in part by the International Science and Technology Cooperation Program of China (Grant No. 2015DFA61800).

  19. Transmission properties of hollow-core photonic bandgap fibers

    DEFF Research Database (Denmark)

    Falk, Charlotte Ijeoma; Hald, Jan; Petersen, Jan C.;

    2010-01-01

    Variations in optical transmission of four types of hollow-core photonic bandgap fibers are measured as a function of laser frequency. These variations influence the potential accuracy of gas sensors based on molecular spectroscopy in hollow-core fibers.......Variations in optical transmission of four types of hollow-core photonic bandgap fibers are measured as a function of laser frequency. These variations influence the potential accuracy of gas sensors based on molecular spectroscopy in hollow-core fibers....

  20. Sheet Plasma Produced by Hollow Cathode Discharge

    Institute of Scientific and Technical Information of China (English)

    张龙; 张厚先; 杨宣宗; 冯春华; 乔宾; 王龙

    2003-01-01

    A sheet plasma is produced by a hollow cathode discharge under an axial magnetic field.The plasma is about 40cm in length,4 cm in width and 1cm in thickness.The electron density is about 108cm-3.The hollow cathode is made to be shallow with a large opening,which is different from the ordinary deep hollow cathode.A Langmuir probe is used to detect the plasma.The electron density and the spatial distribution of the plasma change when voltage,pressure and the magnetic field vary.A peak and a data fluctuation at about 200 G-300 G are observed in the variation of electron density(or thickness of the sheet plasma)with the magnetic field.Our work will be helpful in characterizing the sheet plasma and will make the production of dense sheet plasma more controllable.

  1. Hollow cathode ion source without magnetic field

    International Nuclear Information System (INIS)

    On the base of the IBM-4 ion source a hollow cathode source operating in the continuous regime is developed. The gas discharge chamber diameter equals 100 mm, chamber height - 50 mm. A hollow cathode represents a molybdenum tube with an internal diameter 13 mm and wall thickness 0,7-0,8 mm. An emitter is manufactured from zirconium carbide and lanthanum hexaboride. The investigations of the source operation have shown both cathodes operated efficiency. Electron emission density consitutes 25 A/cm2. At the 50 A discharge current ion current density in a center of plasma emitter constitutes 120 mA/cm2. As a result of the investigations carried out the compatibility of the hollow cathode and the IBM-type source is shown

  2. Sheet plasma produced by hollow cathode discharge

    International Nuclear Information System (INIS)

    A sheet plasma is produced by a hollow cathode discharge under an axial magnetic field. The plasma is about 40 cm in length, 4 cm in width and 1 cm in thickness. The electron density is about 108 cm-3. The hollow cathode is made to be shallow with a large opening, which is different from the ordinary deep hollow cathode. A Langmuir probe is used to detect the plasma. The electron density and the spatial distribution of the plasma change when voltage, pressure and the magnetic field vary. A peak and a data fluctuation at about 200 G - 300 G are observed in the variation of electron density (or thickness of the sheet plasma) with the magnetic field. Our work will be helpful in characterizing the sheet plasma and will make the production of dense sheet plasma more controllable

  3. Comparative Study of Wear Resistance of Sewing Needles

    Institute of Scientific and Technical Information of China (English)

    FEI Dong-ye; ZHU Shi-gen

    2002-01-01

    Poor wearability is the most serious problem of domestic sewing needle, which is the main reason for their short service lives. The influences of needle materials,microstructures and manufacturing technologies on the wear resistance are analyzed in comparison with foreign sewing needles. A series of suitable measures are proposed to improve the wear resistance.

  4. Mechanics of Flexible Needles Robotically Steered through Soft Tissue

    NARCIS (Netherlands)

    Misra, S.; Reed, K.B.; Schafer, B.W.; Ramesh, K.T.; Okamura, A.M.

    2010-01-01

    The tip asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. This enables robotic needle steering, which can be used in medical procedures to reach subsurface targets inaccessible by straight-line trajectories. However, accurate path planning

  5. Adiabatic Rearrangement of Hollow PV Towers

    Directory of Open Access Journals (Sweden)

    Eric A Hendricks

    2010-10-01

    Full Text Available Diabatic heating from deep moist convection in the hurricane eyewall produces a towering annular structure of elevated potential vorticity (PV. This structure has been referred to as a hollow PV tower. The sign reversal of the radial gradient of PV satisfies the Charney-Stern necessary condition for combined barotropic-baroclinic instability. For thin enough annular structures, small perturbations grow exponentially, extract energy from the mean flow, and lead to hollow tower breakdown, with significant vortex structural and intensity change. The three-dimensional adiabatic rearrangements of two prototypical hurricane-like hollow PV towers (one thick and one thin are examined in an idealized framework. For both hollow towers, dynamic instability causes air parcels with high PV to be mixed into the eye preferentially at lower levels, where unstable PV wave growth rates are the largest. Little or no mixing is found to occur at upper levels. The mixing at lower and middle levels is most rapid for the breakdown of the thin hollow tower, consistent with previous barotropic results. For both hollow towers, this advective rearrangement of PV affects the tropical cyclone structure and intensity in a number of ways. First, the minimum central pressure and maximum azimuthal mean velocity simultaneously decrease, consistent with previous barotropic results. Secondly, isosurfaces of absolute angular momentum preferentially shift inward at low levels, implying an adiabatic mechanism by which hurricane eyewall tilt can form. Thirdly, a PV bridge, similar to that previously found in full-physics hurricane simulations, develops as a result of mixing at the isentropic levels where unstable PV waves grow most rapidly. Finally, the balanced mass field resulting from the PV rearrangement is warmer in the eye between 900 and 700 hPa. The location of this warming is consistent with observed warm anomalies in the eye, indicating that in certain instances the hurricane

  6. Generation of a hollow laser beam by a multimode fiber

    Institute of Scientific and Technical Information of China (English)

    Hongyu Ma; Huadong Cheng; Wenzhuo Zhang; Liang Liu; Yuzhu Wang

    2007-01-01

    A simple method to generate a hollow laser beam by multimode fiber is reported. A dark hollow laser beam is generated from a multimode fiber and the dependence of the output beam profile on the incident angle of laser beam is analyzed. The results show that this hollow laser beam can be used to trap and guide cold atoms.

  7. Strong guiding of light in hollow nanowire Structures

    Institute of Scientific and Technical Information of China (English)

    Liang Chen; James De Leon; Xiaomin Jin

    2007-01-01

    @@ We have theoretically investigated the guiding mode patterns of hollow nanowires. Two types of nanowires,round shape and hexagonal shape, are examined with different combination of outer and inner radii.Because of electric field discontinuity at hollow interfaces and evanescent modes overlap in low refractive index region, strong light guiding and confinement are achieved in both hollow wire structures.

  8. Mesoporous hollow spheres from soap bubbling.

    Science.gov (United States)

    Yu, Xianglin; Liang, Fuxin; Liu, Jiguang; Lu, Yunfeng; Yang, Zhenzhong

    2012-02-01

    The smaller and more stable bubbles can be generated from the large parent bubbles by rupture. In the presence of a bubble blowing agent, hollow spheres can be prepared by bubbling a silica sol. Herein, the trapped gas inside the bubble acts as a template. When the porogen, i.e., other surfactant, is introduced, a mesostructured shell forms by the co-assembly with the silica sol during sol-gel process. Morphological evolution emphasizes the prerequisite of an intermediate interior gas flow rate and high exterior gas flow rate for hollow spheres. The method is valid for many compositions from inorganic, polymer to their composites. PMID:22078340

  9. Scaffold Characteristics for Functional Hollow Organ Regeneration

    Directory of Open Access Journals (Sweden)

    Daniel Eberli

    2010-01-01

    Full Text Available Many medical conditions require surgical reconstruction of hollow organs. Tissue engineering of organs and tissues is a promising new technique without harvest site morbidity. An ideal biomaterial should be biocompatible, support tissue formation and provide adequate structural support. It should degrade gradually and provide an environment allowing for cell-cell interaction, adhesion, proliferation, migration, and differentiation. Although tissue formation is feasible, functionality has never been demonstrated. Mainly the lack of proper innervation and vascularisation are hindering contractility and normal function. In this chapter we critically review the current state of engineering hollow organs with a special focus on innervation and vascularisation.

  10. Hollow electrode loose plate SOFC design

    Energy Technology Data Exchange (ETDEWEB)

    Jaspers, B.C.; Dongen, B.A.M. van; Monaster, G.A. [Seed Capital Investments B.V., Utrecht (Netherlands); Roosmalen, J.A.M. van; Plaisier, K.H.; Schoonman, J. [Delft Univ. of Technology (Netherlands). Lab. for Applied Inorganic Chemistry

    1995-12-31

    A novel planar SOFC design is presented, based on the loose stacking of hollow electrode elements, conventional plate type electrolytes and interconnectors. This facilitates free thermal expansion during operation, and thermal cycling, thereby significantly improving prospects for reliable SOFC operation in power generation practice. Each individual element only consists of one material, eliminating the need for sealing and for matching thermal expansion coefficients of fuel cell components. Application of hollow electrodes results in an inherent manifolding of the gas streams eliminating the need for seals at the fuel cell stack itself. The design has been tested at laboratory scale and a small working prototype fuel cell has been successfully tested.

  11. Can elastography replace fine needle aspiration?

    DEFF Research Database (Denmark)

    Popescu, Alexandru; Săftoiu, Adrian

    2014-01-01

    Endoscopic ultrasound (EUS) is one of the best diagnostic methods for diseases of the digestive tract and surrounding organs. Whereas EUS-guided fine needle aspiration (FNA) has been very useful for providing histological confirmation for previously hard to reach lesions, elastography is aiming...

  12. Relationship between needle phobia and dental anxiety

    NARCIS (Netherlands)

    M. Majstorovic; J.S.J. Veerkamp

    2004-01-01

    Purpose: This cross-sectional study aimed to explain the nature of needle phobia and its relationship in dental phobic children with evidence on age-related differences. Methods: The study used 2,865 patients (52% boys, 48% girls), 4 to 11 years old (mean=7.18 years). The patient sample included ran

  13. Thin needle aspiration biopsy of endocrine organs.

    Science.gov (United States)

    Koss, L G

    1979-01-01

    The purpose of this paper is to summarize the advantages and disadvantages of the fine needle aspiration technique in reference to the endocrine organs. The principles of technique and interpretation are presented. The application of aspiration biopsies to the breast, the prostate, the pancreas and the thyroid are briefly discussed. PMID:485094

  14. The Single Needle Lockstitch Machine. Module 1.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on parts of the machine, one in a series on the single needle lockstitch sewing machine for student self-study, contains eight sections. Each section contains the following parts: an introduction, directions, an objective, learning activities, student information, student self-check, check-out activities, and an instructor's final…

  15. Buffon Needle Problem Application to Space Exploration

    CERN Document Server

    Sedelnikov, A V

    2010-01-01

    In this article the possibility of application of classical Buffon needle problem to the investigation of orientation engine firing problem has been investigated. Such an approach makes it possible to get a reliable EP of this undesired event without using a more complicated analysis.

  16. Particulate contamination of sterile syringes and needles.

    Science.gov (United States)

    Taylor, S A

    1982-08-01

    Commercially available sterile needles and syringes have been examined for particulate contamination using the Hiac light blockage technique. The number of particles delivered was small compared with the total number permitted for large volume parenterals. Where syringes are used in particle counting techniques, the contribution of particles should be taken into account. PMID:6126558

  17. Usefulness of multifunctional gastrointestinal coil catheter for colorectal stent placement

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae-Hyung; Shin, Ji Hoon; Kim, Jin Hyoung; Lim, Jin-Oh; Kim, Kyung Rae [Asan Medical Center, Radiology and Research Institute of Radiology, Seoul (Korea); Song, Ho-Young [Asan Medical Center - Radiology, Songpa-gu, Seoul (Korea); Park, In Kook [Dongguk University, Life Science, Seoul (Korea); Choi, Eugene K. [Weill Medical College of Cornell University, New York, NY (United States)

    2008-11-15

    The purpose of this study was to evaluate the usefulness of a multifunctional gastrointestinal coil catheter for stent placement in 98 patients with colorectal strictures. The catheter was used in 98 consecutive patients for stent placement in the rectum (n = 24), recto-sigmoid (n = 13), sigmoid (n = 38), descending (n = 6), transverse (n = 11), splenic flexure (n = 3), hepatic flexure (n = 2), and ascending (n = 1) colon. The catheter was made of a stainless steel coil (1.3 mm in inner diameter), a 0.4-mm nitinol wire, a polyolefin tube, and a hemostasis valve. Usefulness of the catheter was evaluated depending on whether the catheter could pass a stricture over a guide wire and whether measurement of the stricture length was possible. The passage of the catheter over a guide wire beyond the stricture was technically successful and well tolerated in 93 (94.9%) of 98 patients. In the failed five patients, it was not possible to negotiate the guide wire due to presence of nearly complete small bowel obstruction. The average length of stricture was 6.15 cm (range, 3 cm to 20 cm) in patients with the colorectal stricture. There were no procedure-related complications. In conclusion, the multifunctional coil catheter seems to be useful in colorectal stent placement. (orig.)

  18. Percutaneous catheter drainage of intraabdominal abscesses and fluid

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tae; Kwon, Tae Hee; Yoo, Hyung Sik; Suh, Jung Ho [Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Young Ho [Cheil General Hospital, Seoul (Korea, Republic of)

    1986-10-15

    Percutaneous catheter drainage has been reported to be an effective method in the management of selected patients with abscess and fluid collection. Its high success rate and relatively low complications make the procedure an alternative to surgery in the individual cases. During past two years percutaneous catheter drainage in 25 patients with intraabdominal abscesses and fluid collection was performed at the Department of Radiology, Yonsei University College of medicine. Here the technique and author's results were summarized. 1. The total 25 patients who had percutaneous catheter drainage are 10 liver abscesses, 3 subphrenic, one subhepatic, 4 renal and perirenal, 2 pelvic, one psoas, one anterior pararenal fluid from acute pancreatitis, one pancreas pseudocyst and 2 malignant tumor necrosis. 2. The modified Seldinger technique used for all cases of abscess and fluid drainage under guidance of ultrasound scan. The used catheters were 10F. Pigtail and 14F. Malecot (Cook c/o) catheters. 3. The abscesses and fluid of 17 patients among 25 were cured by the percutaneous catheter drainage and 4 patients were clinically improved. The catheter drainage was failed in 2 patients and 3 complication were developed. 4. The success rate of this procedure was 91.3%, failure rate was 8.7% and complication rate was 12%.

  19. Protecting short-term intravascular ear catheters in healthy rabbits.

    Science.gov (United States)

    Sampieri, Francesca; Orchard, Rekha N; Antonopoulos, Aphroditi J; Hamilton, Donald L

    2012-01-20

    Researchers may place a catheter in the ear vessel of a rabbit for a short period of time in order to collect repeated blood samples without extensive restraint of the animal. Maintaining such a catheter in a healthy rabbit can be challenging, as the animal may scratch at the ear, removing the catheter or forming a large hematoma that might impede blood sampling. The authors developed a technique for protecting the indwelling catheter by cutting a section of moleskin to the same shape as the ear and gluing it to the surface of the ear and the catheter. They applied this technique to collect multiple blood samples during 12-h periods from nine rabbits in a pharmacokinetics study. Catheters remained patent in five rabbits for 12 h, in two rabbits for 8 h, in one rabbit for 6 h and in one rabbit for 4 h. This technique allowed for collection of repeated blood samples and prevented the rabbits from interfering with the catheter while allowing them to move freely during the sampling period.

  20. Modified multipurpose catheter enhances clinical utility for cardiac catheterizations.

    Science.gov (United States)

    Mannino, S C; Scavina, M; Palmer, S

    1994-10-01

    The Multipurpose technique for coronary arteriography employs a single catheter. The benefits are a reduction in the cost of the procedure and a shorter procedural time by experienced operators. To enhance the performance of these catheters, a modification was made in the materials and tip design, and these modifications were clinically evaluated in a small study. Compared to the control group of patients (n = 41), patients catheterized with the Multipurpose-SM (n = 43) were shown to have a shorter procedural time as measured by a reduced fluoroscopy time (7.08 min vs. 9.52 min, P = .007). This difference is statistically significant at a 95% confidence level and resulted in less radiation exposure to the operator and cath lab staff. The procedural time was significantly reduced by fewer catheter exchanges (19% study vs. 46% control; P = .006), which were needed to successfully complete the procedure. The new Multipurpose-SM catheter also demonstrated enhanced flexibility for cannulating coronary arteries with superior or anterior takeoffs. This study concludes that the utilization of a modified Multipurpose-SM catheter is safe and effective in cannulating both the left and right coronary arteries, bypass grafts, and performing left ventriculography. The primary benefits of using this modified catheter are reduced fluoroscopy time and the need for fewer catheter exchanges. PMID:7834732

  1. Needle core biopsy for breast lesions: An audit of 467 needle core biopsies

    OpenAIRE

    Selvi Radhakrishna; Anu Gayathri; Deepa Chegu

    2013-01-01

    Background: Breast cancer is the commonest cancer among women in urban India. Triple assessment includes clinical, radiological and cytological assessment of breast lesions. Guided core needle biopsy has replaced fine needle aspiration cytology in most of the western countries. In resource poor countries FNAC is still a very valuable and cost effective method to diagnose breast lesions. Pitfalls include increased rates of non diagnostic smears, and inadequate smears. Further procedures may be...

  2. Distributed parameter statics of magnetic catheters.

    Science.gov (United States)

    Tunay, Ilker

    2011-01-01

    We discuss how to use special Cosserat rod theory for deriving distributed-parameter static equilibrium equations of magnetic catheters. These medical devices are used for minimally-invasive diagnostic and therapeutic procedures and can be operated remotely or controlled by automated algorithms. The magnetic material can be lumped in rigid segments or distributed in flexible segments. The position vector of the cross-section centroid and quaternion representation of an orthonormal triad are selected as DOF. The strain energy for transversely isotropic, hyperelastic rods is augmented with the mechanical potential energy of the magnetic field and a penalty term to enforce the quaternion unity constraint. Numerical solution is found by 1D finite elements. Material properties of polymer tubes in extension, bending and twist are determined by mechanical and magnetic experiments. Software experiments with commercial FEM software indicate that the computational effort with the proposed method is at least one order of magnitude less than standard 3D FEM.

  3. Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure

    Energy Technology Data Exchange (ETDEWEB)

    Burton, Kirsteen R. [University Health Network, University of Toronto, Department of Medical Imaging, Division of Vascular and Interventional Radiology (Canada); Guo, Lancia L. Q. [University of Calgary, Department of Radiology (Canada); Tan, Kong T.; Simons, Martin E.; Sniderman, Kenneth W.; Kachura, John R.; Beecroft, John R.; Rajan, Dheeraj K., E-mail: dheeraj.rajan@uhn.on.ca [University Health Network, University of Toronto, Department of Medical Imaging, Division of Vascular and Interventional Radiology (Canada)

    2012-12-15

    Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.

  4. Hematologic patients' clinical and psychosocial experiences with implanted long-term central venous catheter

    DEFF Research Database (Denmark)

    Møller, Tom; Adamsen, Lis

    2010-01-01

    A significant decrease in catheter-related infections was demonstrated in our earlier randomized controlled trial of central venous catheter (CVC) care in hematologic patients.......A significant decrease in catheter-related infections was demonstrated in our earlier randomized controlled trial of central venous catheter (CVC) care in hematologic patients....

  5. Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure

    International Nuclear Information System (INIS)

    Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.

  6. Ion beam sputter-etched ventricular catheter for hydrocephalus shunt

    Science.gov (United States)

    Banks, B. A. (Inventor)

    1983-01-01

    A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

  7. Fabrication of AlN/BN bishell hollow nanofibers by electrospinning and atomic layer deposition

    Directory of Open Access Journals (Sweden)

    Ali Haider

    2014-09-01

    Full Text Available Aluminum nitride (AlN/boron nitride (BN bishell hollow nanofibers (HNFs have been fabricated by successive atomic layer deposition (ALD of AlN and sequential chemical vapor deposition (CVD of BN on electrospun polymeric nanofibrous template. A four-step fabrication process was utilized: (i fabrication of polymeric (nylon 6,6 nanofibers via electrospinning, (ii hollow cathode plasma-assisted ALD of AlN at 100 °C onto electrospun polymeric nanofibers, (iii calcination at 500 °C for 2 h in order to remove the polymeric template, and (iv sequential CVD growth of BN at 450 °C. AlN/BN HNFs have been characterized for their chemical composition, surface morphology, crystal structure, and internal nanostructure using X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and selected area electron diffraction. Measurements confirmed the presence of crystalline hexagonal BN and AlN within the three dimensional (3D network of bishell HNFs with relatively low impurity content. In contrast to the smooth surface of the inner AlN layer, outer BN coating showed a highly rough 3D morphology in the form of BN nano-needle crystallites. It is shown that the combination of electrospinning and plasma-assisted low-temperature ALD/CVD can produce highly controlled multi-layered bishell nitride ceramic hollow nanostructures. While electrospinning enables easy fabrication of nanofibrous template, self-limiting reactions of plasma-assisted ALD and sequential CVD provide control over the wall thicknesses of AlN and BN layers with sub-nanometer accuracy.

  8. Optimizing resistance of round hollow wire at high frequency

    Institute of Scientific and Technical Information of China (English)

    FENG Yong-jian; ZHANG Tao

    2003-01-01

    The results and methods of calculation of resistance of hollow wire in gigahertz range by Bessel function are given. According to the results of computation, it is found that the resistor of conductor can be optimized using hollow wire with specific wall thickness. At high frequency the current distribution across a circular hollow wire is at surface of wire, which is called skin depth. We found that optimum wall thickness is proportional to skin depth and the phase abrupt change point of H field. Theoretical analysis and mechanism optimized round hollow wire will be presented in this paper. The calculation indicates that cylindrical hollow wire can be optimized to decrease resistance above 8%.

  9. Placing of tunneled central venous catheters prior to induction chemotherapy in children with acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Handrup, Mette Møller; Møller, Jens Kjølseth; Frydenberg, Morten;

    2010-01-01

    BACKGROUND: Tunneled central venous catheters (CVCs) are inevitable in children with acute lymphoid leukemia (ALL). The aim of this study was to evaluate the risk of CVC-related complications in children with ALL in relation to timing of catheter placement and type of catheter. PROCEDURE: All...... children hospitalized from January 2000 to March 2008 with newly diagnosed ALL and with double-lumen total implantable devices (TIDs) or tunneled external catheters (TEs) were included retrospectively. We only used data related to the patient's first catheter. RESULTS: We included 98 children; 35 received...... a TID and the remaining 63 received a TE. A total number of 29,566 catheter days and 93 catheter-associated blood stream infections (CABSI) was identified. We found a CABSI rate of 3.1/1,000 catheter days (5.4/1,000 catheter days for TEs and 1.4/1,000 catheter days for TIDs, incidence rate ratio (IRR) 3...

  10. The impact of sodium citrate on dialysis catheter function and frequency of catheter-related bacteriemia and haemorrhage

    Directory of Open Access Journals (Sweden)

    Maciej Szymczak

    2009-10-01

    Full Text Available Vascular access is one of the most important problems of hemodialysis therapy. It is known that an arteriovenous fi sutla provides the best vascular access, but its creation is not always possible. Other solutions, such as the insertion of a central venous catheter, are then required. Adequate protection of such catheters by interdialytic fi ll with locking solution affects the frequency of hemodialysis-related complications. The most widespread catheter locking solution is heparin. Sodium citrate is being used more frequent recently. Available data indicate that hemorrhage is 11.9 times more frequent if the catheter locking solution is 5000 IU/ml heparin than if 4�0sodium citrate or 1000 IU/ml heparin is used. Other data indicate that the frequency of infection is statistically decreased when 30�0sodium citrate is used to fi ll the catheter instead of 5000 IU/ml heparin. Analogous data on 46.7�0sodium citrate are not consistent. It seems that the use of 4�0sodium citrate instead of 5000 IU/ml heparin does not decrease the frequency of infections. Numerous studies indicate that sodium citrate at various concentrations exerts a positive infl lence on catheter function. However, not all data are in accord. The spill of sodium citrate from the catheter to the systemic circulation is connected with a risk of adverse events. It may be dangerous if the citrate concentration is 46.7�20However, adequate fi lling of the catheter should prezent such events. Available data indicate that fi lling of the catheter with a solution of citrate of a concentration of no more than 30�0should be safe. Data on 46.7�0citrate are not conclusive, so precautions should be taken.

  11. The research of knitting needle status monitoring setup

    Science.gov (United States)

    Liu, Lu; Liao, Xiao-qing; Zhu, Yong-kang; Yang, Wei; Zhang, Pei; Zhao, Yong-kai; Huang, Hui-jie

    2013-09-01

    In textile production, quality control and testing is the key to ensure the process and improve the efficiency. Defect of the knitting needles is the main factor affecting the quality of the appearance of textiles. Defect detection method based on machine vision and image processing technology is universal. This approach does not effectively identify the defect generated by damaged knitting needles and raise the alarm. We developed a knitting needle status monitoring setup using optical imaging, photoelectric detection and weak signal processing technology to achieve real-time monitoring of weaving needles' position. Depending on the shape of the knitting needle, we designed a kind of Glass Optical Fiber (GOF) light guides with a rectangular port used for transmission of the signal light. To be able to capture the signal of knitting needles accurately, we adopt a optical 4F system which has better imaging quality and simple structure and there is a rectangle image on the focal plane after the system. When a knitting needle passes through position of the rectangle image, the reflected light from needle surface will back to the GOF light guides along the same optical system. According to the intensity of signals, the computer control unit distinguish that the knitting needle is broken or curving. The experimental results show that this system can accurately detect the broken needles and the curving needles on the knitting machine in operating condition.

  12. Accuracy of needle position measurements using fiber Bragg gratings.

    Science.gov (United States)

    Henken, Kirsten; Van Gerwen, Dennis; Dankelman, Jenny; Van Den Dobbelsteen, John

    2012-11-01

    Accurate placement of the needle tip is essential in percutaneous therapies such as radiofrequency ablation (RFA) of liver tumors. Use of a robotic system for navigating the needle could improve the targeting accuracy. Real-time information on the needle tip position is needed, since a needle deflects during insertion in tissue. Needle shape can be reconstructed based on strain measurements within the needle. In the current experiment we determined the accuracy with which the needle tip position can be derived from strain measurements using Fiber Bragg Gratings (FBGs). Three glass fibers equipped with two FBGs each were incorporated in a needle. The needle was clamped at one end and deformed by applying static radial displacements at one or two locations. The FBG output was used for offline estimation of the needle shape and tip position. During deflections of the needle tip up to 12.5 mm, the tip position was estimated with a mean accuracy of 0.89 mm (std 0.42 mm). Adding a second deflection resulted in an error of 1.32 mm (std 0.48 mm). This accuracy is appropriate for applications such as RFA of liver tumors. The results further show that the accuracy can be improved by optimizing the placement of FBGs. PMID:22455615

  13. Method for preparing hollow metal oxide microsphere

    Science.gov (United States)

    Schmitt, C.R.

    1974-02-12

    Hollow refractory metal oxide microspheres are prepared by impregnating resinous microspheres with a metallic compound, drying the impregnated microspheres, heating the microspheres slowly to carbonize the resin, and igniting the microspheres to remove the carbon and to produce the metal oxide. Zirconium oxide is given as an example. (Official Gazette)

  14. NUTRIENTS CONCENTRATION AND RETRANSLOCATION IN THE Pinus taeda L. NEEDLES

    Directory of Open Access Journals (Sweden)

    Márcio Viera

    2010-03-01

    Full Text Available Aiming at evaluating nutrients concentration and retranslocation in the Pinus taeda L. needles, this study was developed in two stands, in native grass area and in second rotation area, with same species and same age (7.5 years old in Cambará do Sul, RS. The needles were collected in plants in four orthogonal points (South, North, East and West, sampled new needles, mature needles and old needles. The material was dried in a stove, milled and chemically analyzed (macro and micronutrients. The concentrations of N, P, K, B, Cu and Zn had decreased, of Ca, Fe and Mn increased, and the Mg and S have remained constant with the age of the needles. The retranslocation rate (old-new needles was more than 50% for most nutrients, except for Mn and Fe, showed that cumulative effect and the Ca reference element.

  15. Right atrial indwelling catheter for patients requiring long-term intravenous therapy.

    Science.gov (United States)

    Ivey, M F; Adam, S M; Hickman, R O; Gibson, D L

    1978-12-01

    The use of a central venous catheter for long-term intravenous therapy is described. The catheter's history, physical description, and uses are discussed. Also reviewed are complications from use of the catheter, the pharmacist's role in patient teaching, and the procedure for administering medications through the catheter. A listing of drugs administered through the catheter, incompatibility data and patient teaching instructions are also included. PMID:717409

  16. Radiographic signs of non-venous placement of intended central venous catheters in children

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Erin C. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); Taylor, George A. [Boston Children' s Hospital, Department of Radiology, Boston, MA (United States); Harvard Medical School, Department of Radiology, Boston, MA (United States)

    2016-02-15

    Central venous catheters (CVCs) are commonly used in children, and inadvertent arterial or extravascular cannulation is rare but has potentially serious complications. To identify the radiographic signs of arterial placement of CVCs. We retrospectively reviewed seven cases of arterially malpositioned CVCs on chest radiograph. These cases were identified through departmental quality-assurance mechanisms and external consultation. Comparison of arterial cases was made with 127 age-matched chest radiographs with CVCs in normal, expected venous location. On each anteroposterior (AP) radiograph we measured the distance of the catheter tip from the right lateral border of the thoracic spine, and the angle of the vertical portion of the catheter relative to the midline. On each lateral radiograph we measured the angle of the vertical portion of each catheter relative to the anterior border of the thoracic spine. When bilateral subclavian catheters were present, the catheter tips were described as crossed, overlapping or uncrossed. On AP radiographs, arterially placed CVCs were more curved to the left, with catheter tip positions located farther to the left of midline than normal venous CVCs. When bilateral, properly placed venous catheters were present, all catheters crossed at the level of the superior vena cava (SVC). When one of the bilateral catheters was in arterial position, neither of the catheters crossed or the inter-catheter crossover distance was exaggerated. On lateral radiographs, there was a marked anterior angulation of the vertical portion of the catheter (mean angle 37 ± 15 standard deviation [SD] in arterial catheters versus 5.9 ± 8.3 SD in normally placed venous catheters). Useful radiographic signs suggestive of unintentional arterial misplacement of vascular catheters include leftward curvature of the vertical portion of the catheter, left-side catheter tip position, lack of catheter crossover on the frontal radiograph, as well as exaggerated

  17. Collateral damage from Catheter Ablation of Atrial Fibrillation

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    Wanwarang Wongcharoen, MD

    2013-04-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia, contributing to a significant morbidity and mortality. Catheter ablation of the pulmonary veins (PVs and left atrium (LA has been shown to be an effective strategy for the treatment of symptomatic AF. Regardless of technological advances and technique improvement, catheter ablation for AF remains a highly complex procedure and the risk of procedural complications is not negligible. The major complications have been reported to occur in up to 5.2% of procedures. A systematic investigation among 32,569 patients undergoing catheter ablation for AF has demonstrated that mortality is around 0.1%. Nevertheless, the true prevalence of complications is possibly underestimated in retrospective surveys because of recollection bias and other factors. This article will focus on the management of serious complications of catheter AF ablation including PV stenosis, atrioesophageal fistula, cardiac tamponade, stroke and thromboembolic complication

  18. Continuous quality improvement: improving hemodialysis catheter patency using urokinase.

    Science.gov (United States)

    Northsea, C

    1996-12-01

    Opportunities for improvements in patient outcomes through applied continuous quality improvement (CQI) programs are endless and exciting. Improving vascular access outcomes has been a long-standing clinical problem for hemodialysis patients and the nephrology team. During the past few years there has been a dramatic increase in the use of dialysis catheters as permanent accesses for hemodialysis patients. All hemodialysis with dialysis catheters are at risk for catheter occlusion. An innovative, 2-year CQI program was developed, implemented, and designed to improve dialysis catheter patency rates with the use of urokinase. The CQI program resulted in a number of clinical outcomes that were beneficial to the patients and dialysis staff, and were cost-effective to the program.

  19. Suprapubic catheter change resulting in terminal ileal perforation

    Directory of Open Access Journals (Sweden)

    Chih-Peng Chang

    2014-06-01

    Full Text Available Suprapubic cystostomy is commonly performed in patients with neurogenic bladder or bladder outlet obstruction. The most serious complication is bowel injury, which usually occurs during catheter insertion. Bowel perforation during suprapubic catheter exchange is rare. We herein report an extremely rare case of terminal ileal perforation resulting from a change of suprapubic catheter. After insertion of the suprapubic catheter, a feculent material was noted in the terminal ileum. A cystography revealed that the contrast medium passed directly into the terminal ileum and colon. A computed tomographic scan confirmed the presence of a balloon tip in the terminal ileum. Terminal ileum perforation was diagnosed. Emergent laparotomy and loop ileostomy were performed. The patient's recovery was uneventful.

  20. Automatic rupture of unused intraport catheter. Case report.

    Science.gov (United States)

    Pappas, Paris; Dalianis, Nikolaos; Filippou, Dimitrios K; Condiis, Nicolas; Rizos, Spiros; Skandalakis, Panagiotis

    2007-01-01

    Totally Implantable Central Venous Access Devices (Intraports) are commonly used in cancer patients to administer chemotherapy or parenteral nutrition. These devices are placed by Seldinger technique. We report an unusual case of intraport catheter rupture before the use of the device. The ruptured part of the catheter migrated into the left pulmonary vein via right ventricle. The ruptured part was removed by means of interventional radiology before causing any problems to the patient. All the reported ruptures of port catheters refer to port devices that had been used to administer chemotherapy, fluids, or parenteral nutrition. The unique feature of this case is that the catheter had not been used at all. It is of great interest also the removal of the broken part from the pulmonary vein.

  1. Which criteria demand additive stenting during catheter-directed thrombolysis?

    DEFF Research Database (Denmark)

    Bækgaard, N; Just, S; Foegh, P

    2014-01-01

    Many factors are necessary for obtaining satisfactory results after catheter-directed thrombolysis (CDT) for iliofemoral deep venous thrombosis (DVT). Selections of patients, composition of the thrombolytic fluid, anticoagulation per- and post-procedural, recognition and treatment of persistent...

  2. An Exploration of the Needling Depth in Acupuncture: The Safe Needling Depth and the Needling Depth of Clinical Efficacy

    Directory of Open Access Journals (Sweden)

    Jaung-Geng Lin

    2013-01-01

    Full Text Available Objective. To explore the existing scientific information regarding safe needling depth of acupuncture points and the needling depth of clinical efficacy. Methods. We searched the PubMed, EMBASE, Cochrane, Allied and Complementary Medicine (AMED, The National Center for Complementary and Alternative Medicine (NCCAM, and China National Knowledge Infrastructure (CNKI databases to identify relevant monographs and related references from 1991 to 2013. Chinese journals and theses/dissertations were hand searched. Results. 47 studies were recruited and divided into 6 groups by measuring tools, that is, MRI, in vivo evaluation, CT, ultrasound, dissected specimen of cadavers, and another group with clinical efficacy. Each research was analyzed for study design, definition of safe depth, and factors that would affect the measured depths. Depths of clinical efficacy were discussed from the perspective of de-qi and other clinical observations. Conclusions. Great inconsistency in depth of each point measured from different subject groups and tools exists. The definition of safe depth should be established through standardization. There is also lack of researches to compare the clinical efficacy. A well-designed clinical trial selecting proper measuring tools to decide the actual and advisable needling depth for each point, to avoid adverse effects or complications and promote optimal clinical efficacy, is a top priority.

  3. Colonization of Yankauer suction catheters with pathogenic organisms.

    Science.gov (United States)

    Brown, Melissa; Willms, David

    2005-10-01

    Oral suction devices may be fomites for nosocomial infections. This study was designed to evaluate the rate of contamination of Yankauer suction catheters. Among the 20 catheters tested, 16 (80%) yielded cultures for pathogens. Seven (35%) were colonized with multiple pathogens. Among the organisms encountered included methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). These devices should be handled and stored with appropriate care.

  4. Urinary catheter with polyurethane coating modified by ion implantation

    International Nuclear Information System (INIS)

    A low friction urinary catheter that could be used without a lubricant is proposed in this work. A polyurethane coating was synthesised on the surface of a metal guide wire catheter. Ion implantation was applied to surface modify the polyurethane coating. FTIR ATR, wetting angle, AFM and friction tests were used for analysis. Low friction was found to be provided by the formation of a hard carbonised layer on the polyurethane surface

  5. Imaging and management of complications of central venous catheters

    International Nuclear Information System (INIS)

    Central venous catheters (CVCs) provide valuable vascular access. Complications associated with the insertion and maintenance of CVCs includes pneumothorax, arterial puncture, arrhythmias, line fracture, malposition, migration, infection, thrombosis, and fibrin sheath formation. Image-guided CVC placement is now standard practice and reduces the risk of complications compared to the blind landmark insertion technique. This review demonstrates the imaging of a range of complications associated with CVCs and discusses their management with catheter salvage techniques

  6. Clinical Practice Guidelines for Vascular Catheter Infections Treatment.

    Directory of Open Access Journals (Sweden)

    Belkys Rodríguez Llerena

    2009-03-01

    Full Text Available Clinical Practice Guidelines for Vascular Catheter Infections Treatment. It has been defined as the presence of local or systemic signs without other obvious infection site, plus the microbiologic evidence involving the catheter. This document includes a review and update of concepts, main clinical aspects, and treatment and stresses the importance of prophylactic treatment. It includes assessment guidelines focused on the most important aspects to be accomplished.

  7. Continuous shoulder analgesia via an indwelling axillary brachial plexus catheter.

    Science.gov (United States)

    Reuben, S S; Steinberg, R B

    2000-09-01

    Continuous interscalene brachial plexus blockade can provide anesthesia and analgesia in the shoulder region. Difficulty accessing the interscalene space and premature displacement of interscalene catheters may preclude their use in certain situations. We present two case reports in which a catheter was advanced from the axilla along the brachial plexus sheath to the interscalene space to provide continuous cervicobrachial plexus analgesia. In the first case report, previous neck surgery made the anatomic landmarks for performing an interscalene block very difficult. An epidural catheter was advanced from the axillary brachial plexus sheath to the interscalene space under fluoroscopic guidance. This technique provided both intraoperative analgesia for shoulder surgery as well as 24-hour postoperative analgesia by an infusion of 0.125% bupivacaine. In the second case report, a catheter was inserted in a similar fashion from the axillary to the interscalene space to provide 14 days of continuous analgesia in the management of complex regional pain syndrome. We have found that this technique allows us to secure the catheter more easily than with the traditional interscalene approach and thus prevents premature dislodgment. This approach may be a suitable alternative when either an interscalene or an infraclavicular catheter may not be inserted. PMID:11090734

  8. Contact force assessment in catheter ablation of atrial fibrillatio

    Directory of Open Access Journals (Sweden)

    Josef Kautzner; Petr Peichl

    2014-04-01

    Full Text Available The efficacy of catheter ablation of atrial fibrillation (AF remains limited. Increase of success would require more durable lesions without increased risk of steam pop and cardiac perforation. Recently, novel technologies have been developed to estimate real-time catheter-tissue contact force (CF. This paper reviews three available tools for assessment of CF and data on experimental or clinical experience. Experimental data with open-irrigated catheter showed that lesion size was greater with applications of lower power (like 30 W and greater CF (e.g. 30 to 40 g than vice versa. Impedance drop in the first 5 seconds was significantly correlated to catheter CF. Perforation was achieved more rapidly with the ablation catheter in a sheath despite the same CF because the sheath prevents catheter buckling. Clinical experience confirmed poor relationship between CF and either unipolar amplitude, bipolar amplitude, or impedance. Within the left atrium, the most common high CF site was found at the anterior/rightward LA roof, directly beneath the ascending aorta (confirmed by merging the CT image and map. Importantly, several studies showed that the use of CF leads to shorter procedure with less fluoroscopy time and less RF applications. CF assessment was also found to be associated with higher proportion of durable lesions. Finally, pilot studies showed that CF measurement could be associated with better clinical efficacy AF ablation.

  9. Peripherally Inserted Central Catheters Complicated by Vascular Erosion in Neonates.

    Science.gov (United States)

    Blackwood, Brian P; Farrow, Kathryn N; Kim, Stan; Hunter, Catherine J

    2016-08-01

    Peripherally inserted central catheters (PICCs) are widely used in the pediatric population, and their use continues to grow in popularity. These catheters provide a reliable source of venous access to neonatal patients but can also be the cause of life-threatening complications. There are several well-documented complications such as infections, catheter thrombosis, vascular extravasations, and fractured catheters. However, the complication of vascular erosion into the pleural space using both small and silicone-based catheters is rarely described. After obtaining institutional review board approval, we identified 4 cases to review of PICCs complicated by vascular erosions in the past 2 years. Herein, we also review the current literature of PICC complications. Getting the catheter tip as close to the atrial-caval junction as possible and confirmation of this placement are of the utmost importance. The thick wall of the vena cava near the atrium seems to be less likely to perforate; in addition, this position provides increased volume and turbulence to help dilute the hyperosmolar fluid, which seems to also be a factor in this complication. A daily screening chest x-ray in patients with upper extremity PICCs and ongoing parenteral nutrition (PN) are not necessary at this time given the overall low rate of vascular erosion and concerns regarding excessive radiation exposure in pediatric populations. However, a low threshold for chest x-ray imaging in patients with even mild respiratory symptoms in the setting of upper extremity PN is recommended. PMID:25700180

  10. Important aspects of the colonization of central venous catheter.

    Science.gov (United States)

    Andreoli-Pinto, T J; Graziano, K U

    1999-01-01

    This study comprises five different kind of venous central catheters, 103 in total, made of Polyurethane Tecoflex, Polyurethane Vialon, PTFE and PVC, and the influence of their raw material on the microbial colonization. Patients age and sex, besides their clinical conditions, were taken into account, and neither considered as a sample vicious, nor associated with colonization. When the tips of the catheters were asseptically inoculated in Tryptic Soy Broth and Tioglicolate, colonization was detected in 15.5% of the catheters. Coagulase negative Staphylococcus, some of which with biofilm, were the predominant organisms found, although some bacillus have also been detected: Enterobacter aerogenes, Hafnia alvei, Pseudomonas cepacia, Xanthomonas maltophilia and Aeromonas sobria. It was not possible to notice any association between the colonization of the catheters and their raw material, probably due to the influence of a previous contact and linking with blood components. This contact causes a thin coating on the surface of the cathether, which makes all the catheters similar in respect of the attachment of a bacterial cell. So, the colonization depends on the virulence of the organism, much more then on the nature of the catheter. PMID:10326311

  11. Misplaced central venous catheters: applied anatomy and practical management.

    Science.gov (United States)

    Gibson, F; Bodenham, A

    2013-03-01

    Large numbers of central venous catheters (CVCs) are placed each year and misplacement occurs frequently. This review outlines the normal and abnormal anatomy of the central veins in relation to the placement of CVCs. An understanding of normal and variant anatomy enables identification of congenital and acquired abnormalities. Embryological variations such as a persistent left-sided superior vena cava are often diagnosed incidentally only after placement of a CVC, which is seen to take an abnormal course on X-ray. Acquired abnormalities such as stenosis or thrombosis of the central veins can be problematic and can present as a failure to pass a guidewire or catheter or complications after such attempts. Catheters can also be misplaced outside veins in a patient with otherwise normal anatomy with potentially disastrous consequences. We discuss the possible management options for these patients including the various imaging techniques used to verify correct or incorrect catheter placement and the limitations of each. If the course of a misplaced catheter can be correctly identified as not lying within a vulnerable structure then it can be safely removed. If the misplaced catheter is lying within or traversing large and incompressible arteries or veins, it should not be removed before consideration of what is likely to happen when it is removed. Advice and further imaging should be sought, typically in conjunction with interventional radiology or vascular surgery. With regard to misplaced CVCs, in the short term, a useful aide memoir is: 'if in doubt, don't take it out'.

  12. A retractable barb needle for drug darts

    Directory of Open Access Journals (Sweden)

    G.L. van Rooyen

    1973-07-01

    Full Text Available The mechanism and action of a new retractable barbneedle for drug darts are described. This dart needle is particularly successful in obviating unnecessary flight reactions andtrauma in darted animals, and facilitates the complete injection of the drug dose before the barb is retracted and the dart is dislogded from the animal. The whole process is completed within a few seconds and the expended dart can usually be retrieved in the immediate vicinity where the animal was darted.

  13. Pulmonary actinomycosis in fine needle aspiration cytology

    OpenAIRE

    Patel Keyuri; Gupta Gurudutt; Shah Menka; Patel Purvesh

    2009-01-01

    Pulmonary actinomycosis is a rare bacterial lung disease caused by one of two types of bacteria, Actinomyces or Propioni. Pulmonary actinomycosis in the lung causes lung cavities, lung nodules, and pleural effusion. We report here a case of pulmonary actinomycosis that was diagnosed by fine needle aspiration cytology (FNAC). A 45 year-old male with a history of smoking and alcohol abuse, presented with complaints of cough with hemoptysis, right-sided chest pain, and fever of two months′...

  14. CT Guided Needle Biopsies in Pulmonary Nodules

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    Nargess Afzali

    2011-05-01

    Full Text Available determine the prevalence of pulmonary pathologies"nby CT-guided needle biopsy in pulmonary nodules."nPatients and Methods: We performed CT guided"nneedle biopsy on 78 cases of pulmonary nodules. Lung"nCT scan with a 64-Slice MSCT was done for all patients"nbefore the needle biopsy. All biopsies were performed"nby one experienced interventional radiologist by"nusing a semiautomatic coaxial 18 guage needle. The"nresults were confirmed by two pathologists who were"nunaware of each other's reports. Because of different"npathologic diagnosis two cases were excluded from the"nstudy."nResults: The study population included 43 men and"n33 women with the mean age of 62 years. The mean"nlesion diameter was 22 mm (±7 mm. Thirty-nine"ncases were diagnosed as malignant lesions. Benign"npulmonary conditions were diagnosed in 37 patients."nThe most common malignant lesion was pulmonary"nadenocarcinoma (26%, squamous cell carcinoma"nand bronchoalveolar carcinoma were the next ones."nPulmonary metastasis was seen in three cases and non"nHodgkin lymphoma in three patients. The prevalence"nof adenocarcinoma was not significantly different"nbetween men and women (p value=0.01. The mean age"nof the patients with malignant lesions was 74 years and"n56 years in the others. The difference was significant"n(p=0.05. Tuberculosis was the most common cause of"nbenign lesions (14.4% of all cases, intersitial fibrosis"nand anthracosis were the next most common."nConclusion: Most pulmonary nodules were malignant"nand pulmonary adenocarcinoma was the most"nfrequent. Among benign lesions tuberculosis was the"nmost common."nKeywords: Pulmonary Nodules, Needle Biopsy, CT"nGuide

  15. Exploration of New Electroacupuncture Needle Material

    Directory of Open Access Journals (Sweden)

    Sanghun Lee

    2012-01-01

    Full Text Available Background. Electro Acupuncture (EA uses the acupuncture needle as an electrode to apply low-frequency stimulation. For its safe operation, it is essential to prevent any corrosion of the acupuncture needle. Objective. The aim of this study is to find an available material and determine the possibility of producing a standard EA needle that is biocompatible. Methods. Biocompatibility was tested by an MTT assay and cytotoxicity testing. Corrosion was observed with a scanning electron microscope (SEM after 0.5 mA, 60 min stimulation. The straightness was measured using a gap length of 100 mm, and tensile testing was performed by imposing a maximum tensile load. Results. Phosphor bronze, Ni coated SS304, were deemed inappropriate materials because of mild-to-moderate cytotoxicity and corrosion. Ti-6Al-4V and SS316 showed no cytotoxicity or corrosion. Ti-6Al-4V has a 70 times higher cost and 2.5 times lower conductivity than SS316. The results of both straightness and tensile testing confirmed that SS316 can be manufactured as a standard product. Conclusion. As a result, we confirmed that SS316 can be used a new EA electrode material. We hope that a further study of the maximum capacity of low-frequency stimulation using an SS316 for safe operation.

  16. Exploration of new electroacupuncture needle material.

    Science.gov (United States)

    Lee, Sanghun; Choi, Gwang-Ho; Lee, Chang Hoon; Kim, Yu Kyoung; Lee, Saebhom; Cho, Sungjin; Yeon, Sunhee; Choi, Sun-Mi; Ryu, Yeon-Hee

    2012-01-01

    Background. Electro Acupuncture (EA) uses the acupuncture needle as an electrode to apply low-frequency stimulation. For its safe operation, it is essential to prevent any corrosion of the acupuncture needle. Objective. The aim of this study is to find an available material and determine the possibility of producing a standard EA needle that is biocompatible. Methods. Biocompatibility was tested by an MTT assay and cytotoxicity testing. Corrosion was observed with a scanning electron microscope (SEM) after 0.5 mA, 60 min stimulation. The straightness was measured using a gap length of 100 mm, and tensile testing was performed by imposing a maximum tensile load. Results. Phosphor bronze, Ni coated SS304, were deemed inappropriate materials because of mild-to-moderate cytotoxicity and corrosion. Ti-6Al-4V and SS316 showed no cytotoxicity or corrosion. Ti-6Al-4V has a 70 times higher cost and 2.5 times lower conductivity than SS316. The results of both straightness and tensile testing confirmed that SS316 can be manufactured as a standard product. Conclusion. As a result, we confirmed that SS316 can be used a new EA electrode material. We hope that a further study of the maximum capacity of low-frequency stimulation using an SS316 for safe operation. PMID:22675386

  17. Gamma radiation-sterilized, triple-lumen catheters coated with a low concentration of chlorhexidine were not efficacious at preventing catheter infections in intensive care unit patients.

    OpenAIRE

    Sherertz, R J; Heard, S O; Raad, I I; Gentry, L; Bowton, D; Scuderi, P; Hu, J.; Carruth, W; Satishchandra, B; J. Pepe; Mosenthal, A; Burke, T.; Dupuis, J.

    1996-01-01

    In a randomized, double-blind trial, gamma radiation-sterilized, chlorhexidine-coated triple-lumen catheters were compared with uncoated control catheters for their ability to prevent catheter infection in 254 intensive care unit patients. The chlorhexidine coating was not efficacious, and a rabbit model demonstrated that reduction of chlorhexidine activity by gamma radiation sterilization was the likely explanation for the failure.

  18. Ultrasound-guided robot for flexible needle steering.

    Science.gov (United States)

    Neubach, Zipi; Shoham, Moshe

    2010-04-01

    The success rate of medical procedures involving needle insertion is often directly related to needle placement accuracy. Due to inherent limitations of commonly used freehand needle placement techniques, there is a need for a system providing for controlled needle steering for procedures that demand high positional accuracy. This paper describes a robotic system developed for flexible needle steering inside soft tissues under real-time ultrasound imaging. An inverse kinematics algorithm based on a virtual spring model is applied to calculate needle base manipulations required for the tip to follow a curved trajectory while avoiding physiological obstacles. The needle tip position is derived from ultrasound images and is used in calculations to minimize the tracking error, enabling a closed-loop needle insertion. In addition, as tissue stiffness is a necessary input to the control algorithm, a novel method to classify tissue stiffness from localized tissue displacements is proposed and shown to successfully distinguish between soft and stiff tissue. The system performance was experimentally verified by robotic manipulation of the needle base inside a phantom with layers of varying stiffnesses. The closed-loop experiment with updated tissue stiffness parameters demonstrated a needle-tip tracking error of approximately 1 mm and proved to be significantly more accurate than the freehand method. PMID:19709957

  19. Investigation of biofilm formation on a charged intravenous catheter relative to that on a similar but uncharged catheter

    Directory of Open Access Journals (Sweden)

    Richards GA

    2014-06-01

    Full Text Available Guy A Richards,1,2 Adrian J Brink,3 Ross McIntosh,4 Helen C Steel,5,6 Riana Cockeran5,61Department of Critical Care, Charlotte Maxeke Johannesburg Academic Hospital, 2Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 3Department of Clinical Microbiology, Ampath National Laboratory Services, Milpark Hospital, Johannesburg, South Africa; 4Nano-Scale Transport Physics Laboratory, School of Physics, University of the Witwatersrand, Johannesburg, South Africa; 5Medical Research Council Unit for Inflammation and Immunity, Department of Immunology, University of Pretoria, Pretoria, South Africa; 6National Health Laboratory Service, Pretoria, South AfricaAbstract: Catheter-related blood stream infections increase morbidity, mortality, and costs. This study investigated whether Certofix® protect antimicrobial catheters carry a surface charge and whether this inhibits biofilm formation. The capacitance of the catheter surfaces was measured and, to determine if the catheters released ions, distilled water was passed through and current measured as a function of voltage. With probes touching the inner and outer surfaces, capacitance was not voltage-dependent, indicating surfaces were uncharged or carried a similar charge. When one probe penetrated the catheter wall, capacitance was weakly voltage-dependent, indicating the presence of a surface charge. Standard and charged catheters were also exposed to phosphate buffered saline as controls or 2×106 colony forming units/mL (in phosphate buffered saline of six different microorganisms for 60 or 120 minutes. When the growth of detached bacteria was measured, biofilm formation was significantly reduced, (P<0.05, for charged catheters for all organisms.Keywords: central venous catheters, electrical charge, biofilm

  20. The effects of needle deformation during lumbar puncture

    Directory of Open Access Journals (Sweden)

    Hasan Hüseyin Özdemir

    2015-01-01

    Full Text Available Objective: The aim of this study is to assess deformation of the tip and deflection from the axis of 22-gauge Quincke needles when they are used for diagnostic lumbar puncture (LP. Thus, it can be determined whether constructional alterations of needles are important for predicting clinical problems after diagnostic LP. Materials and Methods: The 22-gauge Quincke needles used for diagnostic LP were evaluated. A specially designed protractor was used for measurement and evaluation. Waist circumference was measured in each patient. Patients were questioned about headaches occurring after LP. Results: A total of 115 Quincke-type spinal needles used in 113 patients were evaluated. No deflection was detected in 38 (33.1% of the needles. Deflection between 0.1° and 5° occurred in 43 (37.3% of the needles and deflection ≥ 5.1° occurred in 34 patients (29.6%. Forty-seven (41.5% patients experienced post lumbar puncture headache (PLPH and 13 (11.5% patients experienced intracranial hypotension (IH. No statistically significant correlation between the degree of deflection and headache was found (P > 0.05. Epidural blood patch was performed for three patients. Deformity in the form of bending like a hook occurred in seven needles and IH occurred in six patients using these needles. Two of the needles used in three patients requiring blood patch were found to be bent. Conclusion: Deformation of needles may increase complications after LP. Needle deformation may lead to IH. In case of deterioration in the structure of the needle, termination of the puncture procedure and the use of a new needle could reduce undesirable clinical consequences, especially IH.

  1. The effects of needle deformation during lumbar puncture

    Science.gov (United States)

    Özdemir, Hasan Hüseyin; Demir, Caner F.; Varol, Sefer; Arslan, Demet; Yıldız, Mustafa; Akil, Eşref

    2015-01-01

    Objective: The aim of this study is to assess deformation of the tip and deflection from the axis of 22-gauge Quincke needles when they are used for diagnostic lumbar puncture (LP). Thus, it can be determined whether constructional alterations of needles are important for predicting clinical problems after diagnostic LP. Materials and Methods: The 22-gauge Quincke needles used for diagnostic LP were evaluated. A specially designed protractor was used for measurement and evaluation. Waist circumference was measured in each patient. Patients were questioned about headaches occurring after LP. Results: A total of 115 Quincke-type spinal needles used in 113 patients were evaluated. No deflection was detected in 38 (33.1%) of the needles. Deflection between 0.1° and 5° occurred in 43 (37.3%) of the needles and deflection ≥ 5.1° occurred in 34 patients (29.6%). Forty-seven (41.5%) patients experienced post lumbar puncture headache (PLPH) and 13 (11.5%) patients experienced intracranial hypotension (IH). No statistically significant correlation between the degree of deflection and headache was found (P > 0.05). Epidural blood patch was performed for three patients. Deformity in the form of bending like a hook occurred in seven needles and IH occurred in six patients using these needles. Two of the needles used in three patients requiring blood patch were found to be bent. Conclusion: Deformation of needles may increase complications after LP. Needle deformation may lead to IH. In case of deterioration in the structure of the needle, termination of the puncture procedure and the use of a new needle could reduce undesirable clinical consequences, especially IH. PMID:25883480

  2. Catheter guided by optical coherence domain reflectometry

    Science.gov (United States)

    Everett, Matthew; Colston, Billy W.; Da Silva, Luiz B.; Matthews, Dennis

    2002-01-01

    A guidance and viewing system based on multiplexed optical coherence domain reflectometry is incorporated into a catheter, endoscope, or other medical device to measure the location, thickness, and structure of the arterial walls or other intra-cavity regions at discrete points on the medical device during minimally invasive medical procedures. The information will be used both to guide the device through the body and to evaluate the tissue through which the device is being passed. Multiple optical fibers are situated along the circumference of the device. Light from the distal end of each fiber is directed onto the interior cavity walls via small diameter optics (such as gradient index lenses and mirrored corner cubes). Both forward viewing and side viewing fibers can be included. The light reflected or scattered from the cavity walls is then collected by the fibers and multiplexed at the proximal end to the sample arm of an optical low coherence reflectometer. The system may also be implemented in a nonmedical inspection device.

  3. Fast integrated intravascular photoacoustic/ultrasound catheter

    Science.gov (United States)

    Choi, Changhoon; Cho, Seunghee; Kim, Taehoon; Park, Sungjo; Park, Hyoeun; Kim, Jinmoo; Lee, Seunghoon; Kang, Yeonsu; Jang, Kiyuk; Kim, Chulhong

    2016-03-01

    In cardiology, a vulnerable plaque is considered to be a key subject because it is strongly related to atherosclerosis and acute myocardial infarction. Because conventional intravascular imaging devices exhibit several limitations with regard to vulnerable plaque detection, the need for an effective lipid imaging modality has been continuously suggested. Photoacoustic (PA) imaging is a medical imaging technique with a high level of ultrasound (US) resolution and strong optical contrast. In this study, we successfully developed an integrated intravascular photoacoustic/ultrasound (IV-PAUS) imaging system with a catheter diameter of 1.2 mm for lipid-rich atherosclerosis imaging. An Nd:YAG pulsed laser with an excitation wavelength of 1064 nm was utilized. IV-PAUS offers 5-mm depth penetration and axial and lateral PA imaging resolutions of 94 μm and 203 μm, respectively, as determined by imaging a 6-μm carbon fiber. We initially obtained 3-dimensional (3D) co-registered PA/US images of metal stents. Subsequently, we successfully obtained 3D coregistered PA/US ex vivo images using an iliac artery from a rabbit atherosclerosis model. Accordingly, lipid-rich plaques were sufficiently differentiated from normal tissue in the ex vivo experiment. We validated these findings histologically to confirm the lipid content.

  4. Characteristics of Left-Right Spiral Hollow Cylindrical Roller

    Institute of Scientific and Technical Information of China (English)

    Liming Lu; Qiping Chen; Yujiang Qin

    2015-01-01

    Based on new rolling⁃sliding compound bearings, the wear between the one⁃way spiral hollow cylindrical roller and the ribs of the inner and outer ring of rolling⁃sliding compound bearings is reduced by innovational structural design. A new left⁃right spiral hollow cylindrical roller is proposed to replace the one⁃way spiral hollow cylindrical roller. The finite element analysis models of ordinary cylindrical rollers, one⁃way spiral hollow cylindrical rollers and left⁃right spiral hollow cylindrical rollers are respectively established by ABAQUS. The axial displacement of their center mass and the stress distribution of left⁃right spiral hollow cylindrical rollers are compared and analyzed. Theoretical study results show that this new left⁃right spiral hollow cylindrical roller not only inherits the advantages of one⁃way spiral hollow cylindrical rollers, but also avoids the axial offset and the serious wear of the one⁃way spiral hollow cylindrical roller. And the theory research conclusion is verified by the experiment. The left⁃right spiral hollow cylindrical roller has the advantages to overcome boundary stress concentration like logarithmic convex roller. The rolling⁃sliding compound bearings equipped with the new rollers can be better to adapt to the impact of vibration load.

  5. Fluoroscopically guided transforaminal epidural dry needling for lumbar spinal stenosis using a specially designed needle

    Directory of Open Access Journals (Sweden)

    Ahn Kang

    2010-08-01

    Full Text Available Abstract Background This report describes the methodological approach and clinical application of a minimally invasive intervention to treat lumbar spinal stenosis (LSS. Methods Thirty-four patients with LSS underwent fluoroscopically guided transforaminal epidural dry needling using a specially designed flexed Round Needle. The needle was inserted 8-12 cm lateral to the midline at the level of the stenosis and advanced to a position between the anterior side of the facet joint and pedicle up to the outer-third of the pedicle. The needle was advanced medially and backed laterally within a few millimetres along the canal side of the inferior articular process between the facet joint and pedicle. The procedure was completed when a marked reduction in resistance was felt at the tip of the needle. The procedure was performed bilaterally at the level of the stenosis. Results The average follow-up period was 12.9 ± 1.1 months. The visual analogue scale (VAS pain score was reduced from 7.3 ± 2.0 to 4.6 ± 2.5 points, the Oswestry Disability Index (ODI score decreased from 41.4 ± 17.2 to 25.5 ± 12.6% and the average self-rated improvement was 52.6 ± 33.1%. The VAS scores indicated that 14 (41.2% patients reported a "good" to "excellent" treatment response, while 11 (32.4% had a "good" to "excellent" treatment response on the ODI and 22 (64.7% had a "good" to "excellent" treatment response on the self-rated improvement scale. Conclusions These results suggest that fluoroscopically guided transforaminal epidural dry needling is effective for managing LSS.

  6. Space Charge Mitigation by Hollow Bunches

    CERN Multimedia

    Oeftiger, AO

    2014-01-01

    To satisfy the requirements of the HL-LHC (High Luminosity Large Hadron Collider), the LHC injector chain will need to supply a higher brightness, i.e. deliver the same transverse beam emittances \\epsilon_{x,y} while providing a higher intensity N. However, a larger number of particles per bunch enhances space charge effects. One approach to mitigate the impact of space charge is to change the longitudinal phase space distribution: hollow bunches feature a depleted bunch centre and a densely populated periphery. Thus, the spatial line density maximum is depressed which ultimately decreases the tune spread imposed by space charge. Therefore, a higher intensity can be accepted while keeping the same overall space charge tune shift. 3 different methods to create hollow bunches in the PSBooster are simulated.

  7. Characterizing the elasticity of hollow metal nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ji Changjiang; Park, Harold S [Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235 (United States)

    2007-03-21

    We have performed atomistic simulations on solid and hollow copper nanowires to quantify the elastic properties of hollow nanowires (nanoboxes). We analyse variations in the modulus, yield stress and strain for <100> and <110> nanoboxes by varying the amount of bulk material that is removed to create the nanoboxes. We find that, while <100> nanoboxes show no improvement in elastic properties as compared to solid <100>nanowires, <110> nanoboxes can show enhanced elastic properties as compared to solid <110> nanowires. The simulations reveal that the elastic properties of the nanoboxes are strongly dependent on the relative strength of the bulk material that has been removed, as well as the total surface area of the nanoboxes, and indicate the potential of ultralight, high-strength nanomaterials such as nanoboxes.

  8. Needle Fracture during Endoscopic Ultrasound-Guided Fine-Needle Aspiration of Suspicious Thoracic Lymph Nodes

    Directory of Open Access Journals (Sweden)

    Bartosz Adamowicz

    2016-01-01

    Full Text Available Endoscopic ultrasound fine-needle aspiration (EUS-FNA is used to make a cytopathologic diagnosis of suspicious lesions located around the gastrointestinal tract. It is a safe technique with few complications. The most common complications of EUS-FNA are related to pancreatic lesions (pancreatitis, bleeding, and abdominal pain. Rare complications have been noted such as stent malfunction, air embolism, infection, neural and vascular injuries, and tumor cell seeding. There are very few studies examining equipment malfunctions. We report a case of needle fracture during the EUS-FNA of suspicious thoracic lymph nodes in a 79-year-old man investigated for unexplained weight loss.

  9. ACUPOINT TO ACUPOINT PENETRATIVE NEEDLING AND ITS CLINICAL APPLICATION

    Institute of Scientific and Technical Information of China (English)

    汪洪明

    2001-01-01

    Acupoint to acupoint penetrative needling method has a long history in traditional Chinese medicine. Chinese physicians in various dynasties hold that this type of needling method can strengthen the needling sensations and raise the therapeutic effect in clinical practice. This needling method can be divided into straight penetration, oblique penetration and transverse penetration. In clinical application, it can also be divided into external-medial meridian penetration, a single meridian penetration, neighboring meridians penetration, and neighboring aoupoints penetration, etc. in accordance with the involved acupoints and meridians. Clinical practice demonstrates that penetrative needling possesses advantages of stronger needling sensations, better therapeutic effect and fewer aoupoints selection. For this reason, it is extensively applied in clinic.

  10. Knowledge of nursing students about central venous catheters

    Directory of Open Access Journals (Sweden)

    Mlinar Suzana

    2012-01-01

    Full Text Available Background/Aim. Central venous catheters (CVC are at the crucial importance, particulary in the intensive therapy units. In order to handle a CVC safely, nursing students need to acquire theoretical and practical knowledge during the course of their studies. The aim of the study was to establish theoretical knowledge of nursing students about the procedures of nurses in placing and removing a central venous catheter (CVC, dressing the catheter entry point, the reasons for measuring central venous pressure (CVP, possible complications and risk factors for developing infections related to CVC. Methods. The questionnaire developed specifically for this cross-sectionl study was handed out to 87 full-time students and 57 part-time students. Results. The results show that all the surveyed nursing students know why chest radiography is carried out when inserting a catheter, have relatively good knowledge of CVC insertion points, procedures carried out in case of a suspected catheter sepsis and complications and risk factors for the development of infections related to CVC. However, the study show that the majority of students have insufficient knowledge of the procedures accompanying insertion of a catheter, signs that indicate correct functioning of CVC, frequency of flushing a catheter when it is not in use and the reasons for introducing an implanted CVC. Conclusion. Based on the results of the study it can be concluded that the second-year nursing students have insufficient knowledge of CVC. In order to correctly and safely handle a CVC, good theoretical knowledge and relevant practical experience are needed. The authors therefore believe that, in future, the classes should be organized in smaller groups with step-by-step demonstrations of individual procedures in handling a CVC, and the students encouraged to learn as actively as possible.

  11. Hollow Sucker Rod Applied in Production Engineering

    Institute of Scientific and Technical Information of China (English)

    Wang Tongbin; Liu Liandong; Hu Daoming; Jia Yanshan

    1997-01-01

    @@ Working Principle A positive cycle system or a working channel can be formed by means of hollow sucker rod and its mating parts in the oil tube ofa well, through which heat carriers (such as hot water,hot oil and steam), chemicals and heating cable can be pumped or put into the well so as to lower the viscosity of crude, dissolve the paraffin building-up and open the conduit, thus leading to the smooth oil flow out of well.

  12. Wedge - rolls rolling of hollowed parts

    Directory of Open Access Journals (Sweden)

    Z. Pater

    2006-08-01

    Full Text Available Purpose: Presentation of the possibilities of application of a new manufacturing method, called wedge rollsrolling (WRR in forming of axi – symmetrical hollowed parts.Design/methodology/approach: The research work was done in a specially designed laboratory rolling millLUW-2. During the research, hollowed parts from steel were rolled in hot forming conditions. Basic kinematicaland force parameters of the process were noticed during rolling.Findings: On the basis of the conducted research it was stated that the WRR method could be used for formingof hollowed parts with the precision compared with the precision obtained in the typical cross wedge rollingprocesses (CWR. At the same time, it was proved that this method could be used for rolling from billets withthe wall thinner than the wall given in the CWR.Research limitations/implications: The research were limited to the wedges with spreading angles withinrange of β = (5° ÷ 9°, with the constant values of forming angle α = 30° and relative reduction ratio δ = 1.45.In the future, it is planned to analyse the influence of changes of angle α and relative reduction ratio δ on theWRR process.Practical implications: The conducted research can be used for designing of a new industrial method of metalforming of hollowed parts.Originality/value: The innovation of this solution is based on the application of only one wedge for forming.Because of that, the WRR method is cheaper for implementation than used so far CWR processes. This methodcan be applied mainly in automotive and aviation industries.

  13. Hollow Cathode With Multiple Radial Orifices

    Science.gov (United States)

    Brophy, John R.

    1992-01-01

    Improved hollow cathode serving as source of electrons has multiple radial orifices instead of single axial orifice. Distributes ion current more smoothly, over larger area. Prototype of high-current cathodes for ion engines in spacecraft. On Earth, cathodes used in large-diameter ion sources for industrial processing of materials. Radial orientation of orifices in new design causes current to be dispersed radially in vicinity of cathode. Advantageous where desireable to produce plasma more nearly uniform over wider region around cathode.

  14. In vivo Monitoring of Serotonin by Nanomaterial Functionalized Acupuncture Needle

    OpenAIRE

    Yu-Tao Li; Li-Na Tang; Yong Ning; Qing Shu; Feng-Xia Liang; Hua Wang; Guo-Jun Zhang

    2016-01-01

    Acupuncture treatment is amazing but controversial. Up to now, the mechanism of treating diseases by acupuncture and moxibustion is still unclear, especially the occurrence of the molecular events in local acupoints. Herein, we report an extremely stable microsensor by modifying carbon nanotube (CNT) to the tip surface of acupuncture needle and applying this CNT-modified acupuncture needle for real time monitoring of serotonin (5-HT) in vivo. To stabilize CNT modification on the needle tip su...

  15. Lab in a needle for epidural space identification

    Science.gov (United States)

    Carotenuto, B.; Micco, A.; Ricciardi, A.; Amorizzo, E.; Mercieri, M.; Cutolo, A.; Cusano, A.

    2016-05-01

    This work relies on the development of a sensorized medical needle with an all-optical guidance (Lab in a Needle) system for epidural space identification. The device is based on the judicious integration of a Fiber Bragg grating sensor inside the lumen of an epidural needle to discriminate between different types of tissue and thus providing continuous and real time measurements of the pressure experienced by the needle tip during its advancement. Experiments carried out on an epidural training phantom demonstrate the validity of our approach for the correct and effective identification of the epidural space.

  16. Serrated needle design facilitates precise round window membrane perforation.

    Science.gov (United States)

    Stevens, James P; Watanabe, Hirobumi; Kysar, Jeffrey W; Lalwani, Anil K

    2016-07-01

    The round window membrane (RWM) has become the preferred route, over cochleostomy, for the introduction of cochlear implant electrodes as it minimizes inner ear trauma. However, in the absence of a tool designed for creating precise perforation, current practices lead to tearing of the RWM and significant intracochlear pressure fluctuations. On the basis of RWM mechanical properties, we have designed a multi-serrated needle to create consistent holes without membrane tearing or damaging inner ear structures. Four and eight-serrated needles were designed and produced with wire electrical discharge machining (EDM). The needle's ability to create RWM perforations was tested in deidentified, commercially acquired temporal bones with the assistance of a micromanipulator. Subsequently, specimens were imaged under light and scanning electron microscopy (SEM). The needles created consistent, appropriately sized holes in the membrane with minimal tearing. While a four-serrated crown needle made rectangular/trapezoid perforations, the octagonal crown formed smooth oval holes within the membrane. Though designed for single use, the needle tolerated repeated use without significant damage. The serrated needles formed precise perforations in the RWM while minimizing damage during cochlear implantation. The octagonal needle design created the preferred oval perforation better than the quad needle. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1633-1637, 2016. PMID:26914984

  17. Preparation of Nanocrystalline MoS2 Hollow Spheres

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Nanocrystalline MoS2 with hollow spherical morphology has been prepared by the hydrothermal method. The products are characterized by means of X-ray powder diffraction, transmission electron microscopy and high-resolution transmission electron microscopy. The experimental results give the evidence that the sample is consists of hollow spheres 400~600 nm in diameter, and there is much whisker on the surface of MoS2 hollow sphere.

  18. Silica hollow spheres with nano-macroholes like diatomaceous earth.

    Science.gov (United States)

    Fujiwara, Masahiro; Shiokawa, Kumi; Sakakura, Ikuko; Nakahara, Yoshiko

    2006-12-01

    Artificial synthesis of hollow cell walls of diatoms is an ultimate target of nanomaterial science. The addition of some water-soluble polymers such as sodium polymethacrylate to a solution of water/oil/water emulsion system, which is an essential step of the simple synthetic procedure of silica hollow spheres (microcapsules), led to the formation of silica hollow spheres with nano-macroholes (>100 nm) in their shell walls, the morphologies of which are analogous to those of diatom earth.

  19. Review of Synthetic Methods to Form Hollow Polymer Nanocapsules

    Energy Technology Data Exchange (ETDEWEB)

    Barker, Madeline T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-03-13

    Syntactic foams have grown in interest due to the widened range of applications because of their mechanical strength and high damage tolerance. In the past, hollow glass or ceramic particles were used to create the pores. This paper reviews literature focused on the controlled synthesis of hollow polymer spheres with diameters ranging from 100 –200 nm. By using hollow polymer spheres, syntactic foams could reach ultra-low densities.

  20. Antibiofilm surface functionalization of catheters by magnesium fluoride nanoparticles

    Directory of Open Access Journals (Sweden)

    Lellouche J

    2012-03-01

    Full Text Available Jonathan Lellouche1,2, Alexandra Friedman2, Roxanne Lahmi1, Aharon Gedanken2, Ehud Banin11The Mina and Everard Goodman Faculty of Life Sciences, 2The Kanbar Laboratory for Nanomaterials, Department of Chemistry, The Bar-Ilan Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan, IsraelAbstract: The ability of bacteria to colonize catheters is a major cause of infection. In the current study, catheters were surface-modified with MgF2 nanoparticles (NPs using a sonochemical synthesis protocol described previously. The one-step synthesis and coating procedure yielded a homogenous MgF2 NP layer on both the inside and outside of the catheter, as analyzed by high resolution scanning electron microscopy and energy dispersive spectroscopy. The coating thickness varied from approximately 750 nm to 1000 nm on the inner walls and from approximately 450 nm to approximately 580 nm for the outer wall. The coating consisted of spherical MgF2 NPs with an average diameter of approximately 25 nm. These MgF2 NP-modified catheters were investigated for their ability to restrict bacterial biofilm formation. Two bacterial strains most commonly associated with catheter infections, Escherichia coli and Staphylococcus aureus, were cultured in tryptic soy broth, artificial urine and human plasma on the modified catheters. The MgF2 NP-coated catheters were able to significantly reduce bacterial colonization for a period of 1 week compared to the uncoated control. Finally, the potential cytotoxicity of MgF2 NPs was also evaluated using human and mammalian cell lines and no significant reduction in the mitochondrial metabolism was observed. Taken together, our results indicate that the surface modification of catheters with MgF2 NPs can be effective in preventing bacterial colonization and can provide catheters with long-lasting self-sterilizing properties.Keywords: MgF2 NP coating, modified surfaces, bacterial colonization, human plasma

  1. Transversus Abdominis Plane Catheter Bolus Analgesia after Major Abdominal Surgery

    Directory of Open Access Journals (Sweden)

    Nils Bjerregaard

    2012-01-01

    Full Text Available Purpose. Transversus abdominis plane (TAP blocks have been shown to reduce pain and opioid requirements after abdominal surgery. The aim of the present case series was to demonstrate the use of TAP catheter injections of bupivacaine after major abdominal surgery. Methods. Fifteen patients scheduled for open colonic resection surgery were included. After induction of anesthesia, bilateral TAP catheters were placed, and all patients received a bolus dose of 20 mL bupivacaine 2.5 mg/mL with epinephrine 5 μg/mL through each catheter. Additional bolus doses were injected bilaterally 12, 24, and 36 hrs after the first injections. Supplemental pain treatment consisted of paracetamol, ibuprofen, and gabapentin. Intravenous morphine was used as rescue analgesic. Postoperative pain was rated on a numeric rating scale (NRS, 0–10 at regular predefined intervals after surgery, and consumption of intravenous morphine was recorded. Results. The TAP catheters were placed without any technical difficulties. NRS scores were ≤3 at rest and ≤5 during cough at 4, 8, 12, 18, 24, and 36 hrs after surgery. Cumulative consumption of intravenous morphine was 28 (23–48 mg (median, IQR within the first 48 postoperative hours. Conclusion. TAP catheter bolus injections can be used to prolong analgesia after major abdominal surgery.

  2. Port- a- Cath Catheter placement by general surgery residents

    Directory of Open Access Journals (Sweden)

    F. Schlottmann

    2015-04-01

    Full Text Available In recent years an increasing incidence and prevalence of oncological diseases is observed, with a consequent increase in chemotherapies. In order to avoid repeated venipuncture of patients and toxicity in small veins during different cycles of treatment, devices that provide a permanent central venous access are used. The aim of this study was to evaluate the success and safety of port a cath devices inserted by surgery residents. A consecutive case series of patients in whom Port-a-CathTM catheter was placed by residents of surgery in the period from March 2009 to January 2014 were included. A total of 358 Port-a-CathTM catheters were inserted. Average age 58.7 years (16-88. Females 53.1%. Chemotherapy treatment for solid neoplasias (74.8% and for hematological diseases (25.2%. SThe different venous accesses were: Subclavian (67.6%, Cephalic (27.4%, external jugular (3.3%, internal jugular (1.7%. The morbidity rate was 5.3%, twelve patients with catheter-associated infection requiring the removal of it, 3 venous thrombosis with subsequent replacement of the catheter and 4 patients required pleural drainage. Port-a-CathTM catheter placement by residents is a safe and effective procedure for the administration of chemotherapy

  3. Hemodialysis Catheter Heat Transfer for Biofilm Prevention and Treatment.

    Science.gov (United States)

    Richardson, Ian P; Sturtevant, Rachael; Heung, Michael; Solomon, Michael J; Younger, John G; VanEpps, J Scott

    2016-01-01

    Central line-associated bloodstream infections (CLABSIs) are not easily treated, and many catheters (e.g., hemodialysis catheters) are not easily replaced. Biofilms (the source of infection) on catheter surfaces are notoriously difficult to eradicate. We have recently demonstrated that modest elevations of temperature lead to increased staphylococcal susceptibility to vancomycin and significantly soften the biofilm matrix. In this study, using a combination of microbiological, computational, and experimental studies, we demonstrate the efficacy, feasibility, and safety of using heat as an adjuvant treatment for infected hemodialysis catheters. Specifically, we show that treating with heat in the presence of antibiotics led to additive killing of Staphylococcus epidermidis with similar trends seen for Staphylococcus aureus and Klebsiella pneumoniae. The magnitude of temperature elevation required is relatively modest (45-50°C) and similar to that used as an adjuvant to traditional cancer therapy. Using a custom-designed benchtop model of a hemodialysis catheter, positioned with tip in the human vena cava as well as computational fluid dynamic simulations, we demonstrate that these temperature elevations are likely achievable in situ with minimal increased in overall blood temperature. PMID:26501916

  4. Evaluation of the silver iontophoretic catheter in an animal model.

    Science.gov (United States)

    Hachem, Ray Y; Wright, Kenneth C; Zermeno, Alfonso; Bodey, Gerald P; Raad, Issam I

    2003-09-01

    Silver iontophoretic catheters (SIC) were shown to be highly efficacious in preventing catheter infections in vitro and in a rabbit model (J. Infect. Dis. 173 (1996) 495). Furthermore, we sought to determine the safety and durability of SIC prior to use in humans. A total of 30 New Zealand white rabbits (3-4 kg) were randomly assigned to one of three groups whereby SIC or Arrow Guard (AG) catheters were tunneled and inserted in the jugular vein. All animals were followed for 2-12 weeks after catheter implantation. Blood was collected from each rabbit for assessment of toxicity and determination of silver levels. The electrical current generated by each SIC was measured once daily. At the end of the follow-up period, tissue samples were collected from the skin surrounding the catheter, the lungs, spleen, and liver. Microscopically, none of the tissues examined from any of the animals showed evidence of silver deposits, silver toxicity, thermal or electrical injury. The silver levels in the animals that received the SIC ranged from 0.1 to 2.23 microg/l with a mean of 0.62 (+/-0.44 SD). In conclusion SIC were safe with normal serum silver levels and were not associated with any local or systemic toxicity. PMID:12809792

  5. Hemodialysis Catheter Heat Transfer for Biofilm Prevention and Treatment.

    Science.gov (United States)

    Richardson, Ian P; Sturtevant, Rachael; Heung, Michael; Solomon, Michael J; Younger, John G; VanEpps, J Scott

    2016-01-01

    Central line-associated bloodstream infections (CLABSIs) are not easily treated, and many catheters (e.g., hemodialysis catheters) are not easily replaced. Biofilms (the source of infection) on catheter surfaces are notoriously difficult to eradicate. We have recently demonstrated that modest elevations of temperature lead to increased staphylococcal susceptibility to vancomycin and significantly soften the biofilm matrix. In this study, using a combination of microbiological, computational, and experimental studies, we demonstrate the efficacy, feasibility, and safety of using heat as an adjuvant treatment for infected hemodialysis catheters. Specifically, we show that treating with heat in the presence of antibiotics led to additive killing of Staphylococcus epidermidis with similar trends seen for Staphylococcus aureus and Klebsiella pneumoniae. The magnitude of temperature elevation required is relatively modest (45-50°C) and similar to that used as an adjuvant to traditional cancer therapy. Using a custom-designed benchtop model of a hemodialysis catheter, positioned with tip in the human vena cava as well as computational fluid dynamic simulations, we demonstrate that these temperature elevations are likely achievable in situ with minimal increased in overall blood temperature.

  6. Catheter-related infection in gastrointestinal fistula patients

    Institute of Scientific and Technical Information of China (English)

    Ge-Fei Wang; Jian-An Ren; Jun Jiang; Cao-Gan Fan; Xin-Bo Wang; Jie-Shou Li

    2004-01-01

    AIM: To study the incidence, bacterial spectrum and drug sensitivity of catheter-related infection (CRI) in gastrointestinal fistula patients.METHODS: A total of 216 patients with gastrointestinal fistulae during January 1998 to April 2001 were studied retrospectively. Two hundred and sixteen catheters of the 358 central venous catheters used in 216 gastrointestinal fistula patients were sent for microbiology analysis.RESULTS: Ninety-five bacteria were cultivated in 88catheters (24.6%). There were 54 Gram-negative bacteria (56.8%), 35 Gram-positive bacteria (36.8%), and 6 fungi (6.4%). During the treatment of CRI, 20 patients changed to use antibiotics or antifungal, and all patients were cured.The mean time of catheters used was 16.9±13.0 d.CONCLUSION: CRI is still the common complication during total parenteral nutrition (TPN) treatment in patients with gastrointestinal fistulae, and Gram-negative bacteria are the main pathogens, and bacterial translocation is considered the common reason for CRI.

  7. Effect of plastic catheter material on bacterial adherence and viability.

    Science.gov (United States)

    Lopez-Lopez, G; Pascual, A; Perea, E J

    1991-06-01

    The kinetics of adherence of single isolates of Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa and Escherichia coli to catheters made of polyvinyl chloride (PVC), Teflon, siliconised latex, polyurethane and Vialon was evaluated by a radiometric assay. Radiolabelled bacteria (10(8) cfu/ml) were incubated in vials containing 1-cm lengths of catheter for up to 3 days. The peak of maximal adherence to each biomaterial was reached after 24 h for P. aeruginosa and after 72 h for the other strains. Bacterial adherence to PVC and siliconised latex was significantly higher (2-6 times; p less than 0.05) than to the other biomaterials for all the strains. The lowest values of adherence were observed with polyurethane and Vialon for the staphylococci but with Teflon for E. coli and P. aeruginosa. Bacterial viability and growth was evaluated in eluates obtained from incubation of segments of each catheter in buffer for 24 h. None of the eluates affected the viability of the staphylococci. However, all of them, significantly increased the growth of E. coli and P. aeruginosa with the exception of the eluate from siliconised latex, in which the inoculum count was reduced to an undetectable level for E. coli. We conclude that bacterial adherence to catheters may depend in part on the nature of the biomaterial and that certain substances eluted from the catheters may affect the viability and growth of different micro-organisms. PMID:1905357

  8. Rat indwelling urinary catheter model of Candida albicans biofilm infection.

    Science.gov (United States)

    Nett, Jeniel E; Brooks, Erin G; Cabezas-Olcoz, Jonathan; Sanchez, Hiram; Zarnowski, Robert; Marchillo, Karen; Andes, David R

    2014-12-01

    Indwelling urinary catheters are commonly used in the management of hospitalized patients. Candida can adhere to the device surface and propagate as a biofilm. These Candida biofilm communities differ from free-floating Candida, exhibiting high tolerance to antifungal therapy. The significance of catheter-associated candiduria is often unclear, and treatment may be problematic considering the biofilm drug-resistant phenotype. Here we describe a rodent model for the study of urinary catheter-associated Candida albicans biofilm infection that mimics this common process in patients. In the setting of a functioning, indwelling urinary catheter in a rat, Candida proliferated as a biofilm on the device surface. Characteristic biofilm architecture was observed, including adherent, filamentous cells embedded in an extracellular matrix. Similar to what occurs in human patients, animals with this infection developed candiduria and pyuria. Infection progressed to cystitis, and a biofilmlike covering was observed over the bladder surface. Furthermore, large numbers of C. albicans cells were dispersed into the urine from either the catheter or bladder wall biofilm over the infection period. We successfully utilized the model to test the efficacy of antifungals, analyze transcriptional patterns, and examine the phenotype of a genetic mutant. The model should be useful for future investigations involving the pathogenesis, diagnosis, therapy, prevention, and drug resistance of Candida biofilms in the urinary tract.

  9. Heparin Leakage in Central Venous Catheters by Hemodynamic Transport

    Science.gov (United States)

    Barbour, Michael; McGah, Patrick; Gow, Kenneth; Aliseda, Alberto

    2014-11-01

    Central venous catheters (CVCs), placed in the superior vena cava for hemodialysis, are routinely filled with heparin, an anticoagulant, while not in use to maintain patency and prevent thrombus formation at the catheter tip. However, the heparin-lock procedure places the patient at risk for systemic bleeding incidences, as heparin is known to leak into the blood stream. We propose that the driving mechanism behind heparin leakage is advective-diffusive transport due to the pulsatile blood flow surrounding the catheter tip. This novel hypothesis is based on Planar Laser Induced Fluorescence (PLIF) measurements of heparin transport from a CVC placed inside an in vitro pulsatile flow loop and validated with CFD simulations. The results show an initial, fast (catheter lumen, where concentration is still high, that is insufficient at replenishing the lost heparin at the tip. These results, which estimate leakage rates consistent with published in vivo data, predict that the concentration of heparin at the catheter tip is effectively zero for the majority of the interdialytic phase, rendering the heparin lock ineffective.

  10. Manufacturing hollow obturator with resilient denture liner on post hemimaxillectomy

    Directory of Open Access Journals (Sweden)

    Michael Josef Kridanto Kamadjaja

    2006-03-01

    Full Text Available A resilient denture liner is placed in the part of the hollow obturator base that contacts to post hemimaxillectomy mucosa. Replacing the resilient denture liner can makes the hollow obturator has an intimate contact with the mucosa, so it can prevents the mouth liquid enter to the cavum nasi and sinus, also eliminates painful because of using the hollow obturator. Resilient denture liner is a soft and resilient material that applied to the fitting surface of a denture in order to allow a more distribution of load. A case was reported about using the hollow obturator with resilient denture liner on post hemimaxillectomy to overcome these problems.

  11. Risk of Needle-track Seeding After Diagnostic Image-guided Core Needle Biopsy in Breast Cancer

    OpenAIRE

    Knight, Rebecca; Horiuchi, Kent; Parker, Steve H.; Ratzer, Erick R.; Fenoglio, Michael E.

    2002-01-01

    Objective: Image-guided core needle biopsy (IGCNB) is an accepted technique for sampling nonpalpable mammographically detected suspicious breast lesions. However, the concern for needle-track seeding in malignant lesions remains. An alternative to IGCNB is needle-localization breast biopsy (NLBB). No study has been done to compare the local recurrence rate of breast cancer after IGCNB versus NLBB. Methods: We have retrospectively reviewed the local recurrence of breast cancer in patients diag...

  12. Polychlorinated naphthalenes in pine needles from Poland

    Energy Technology Data Exchange (ETDEWEB)

    Orlikowska, A.; Falandysz, J.; Bochentin, I. [Dept. of Environmental Chemistry and Ecotoxicology, Univ. of Gdansk (Poland); Hanari, N.; Wyrzykowska, B.; Yamashita, N. [National Inst. of Advanced Industrial Science and Technology (AIST), EMTECH, Tsukuba (Japan)

    2004-09-15

    Polychlorinated naphthalenes (PCNs) are a group of 75 compounds, which have been commercially produced and used in a wide range of industrial applications for the sake of their specific chemical properties. They are recognized as good electrical insulators and also as water and flame resistant materials. Technical PCNs formulations were mainly used as capacitor dielectrics, engine oil additives, electroplating stop-off compounds, in wire insulations and as paper, wood and fabric preservatives. Moreover, they have been formed during production of PCBs formulations. Although recently most countries have stopped synthesis of PCNs, they still are widely distributed in the environment. Nowadays the principal sources of these compounds are municipal solid wastes incineration, metallurgical and chloro-alkali processes. In last years PCNs concentrations in the environment have posed the cynosure of big group of scientists in the whole world. The relatively high concentrations are regarded as an environmental problem. Because they are persistent, toxic and lipophilic they might be bioaccumulated in living organisms and generate the danger for animals and humans. It is essentially to monitor their levels in air, regional transport, as well as estimate specific sources. It is possible by using as a biomonitors pine tree needles. These trees are considered as the very suitable passive indicators for monitoring of PCNs concentrations in the troposphere. This is because the surface wax layer of the needles poses an ability to absorb these lipophilic compounds from the surrounding air. In the current study pine needles were employed as biomonitors of PCNs concentrations in the ambient air of Poland. This country with its past history of production and use of different applications including these compounds, as well as with its location in the centre of Europe, presents the interesting region to these researches.

  13. Transbronchial needle aspiration "by the books"

    Directory of Open Access Journals (Sweden)

    Kupeli Elif

    2011-01-01

    Full Text Available Background : Training for advanced bronchoscopic procedures is acquired during the interventional pulmonology (IP Fellowship. Unfortunately a number of such programs are small, limiting dissemination of formal training. Objective : We studied success of conventional transbronchial needle aspiration (C-TBNA in the hands of physicians without formal IP training. Methods : A technique of C-TBNA was learned solely from the literature, videos and practicing on inanimate models at "Hands-On" courses. Conventional TBNA with 21 and/or 19 gauge Smooth Shot Needles (Olympus® , Japan was performed on consecutive patients with undiagnosed mediastinal lymphadenopathy. Results : Thirty-four patients (male 23, mean age 54.9 ± 11.8 years underwent C-TBNA. Twenty-two patients had nodes larger than 20 mms. Suspected diagnoses were malignancy in 20 and nonmalignant conditions in 14. Final diagnoses were malignancy 17, sarcoidosis 4, reactive lymph nodes 12, and tuberculosis 1. Final diagnosis was established by C-TBNA in 14 (11 malignancy, 3 sarcoidosis; yield 41.1%, mediastinoscopy in 14, transthoracic needle aspiration in 3, peripheral lymph node biopsies in 2 and by endobronchial biopsy in 1. Nodal size had an impact on outcome (P = 0.000 while location did not (P = 0.33. C-TBNA was positive in 11/20 when malignancy was suspected (yield 55%, while 3/14 when benign diagnosis was suspected (yield 21.4% (P = 0.05. Sensitivity, specificity, PPV, NPV, and diagnostic accuracy were 66.6%, 100%, 100%, 65%, and 79.4%, respectively. There were no complications or scope damage. Conclusion : Conventional-TBNA can be learned by the books and by practicing on inanimate models without formal training and results similar to those published in the literature could be achieved.

  14. Compatibility of electrolytically produced sodium hypochlorite solutions on long- term implanted dialysis catheters.

    Science.gov (United States)

    Mishkin, G J

    2007-01-01

    More than 20% of the world's population use a catheter for dialysis, despite guidelines limiting their use. Although the structure and design of the catheters differ by manufacturer, the material used in central venous catheters and peritoneal dialysis catheters are the same across manufacturers. Given the long-term use of these catheters in the dialysis population, the good compatibility of the antiseptics and disinfectants used on the catheters is imperative to prevent failure and cracking of the catheter material. Tensile strengths of commercially available catheters were measured after exposure to commonly used disinfectants. The tensile strength was then compared between the catheters by analyzing the displacement vs. force (N) curves produced during the evaluation. A total of 44 catheter lumens were evaluated. The electrolytically produced sodium hypochlorite solution, Alcavis 50/ExSept Plus, was the only solution shown to be compatible with all three catheter materials resulting in a deviation of less than 10% for each of the different catheter types. Electrolytically produced sodium hypochlorite solutions were the only solutions in this study that did not alter the physical properties of any of the catheters after long-term exposure. PMID:17099302

  15. Outcome of tunneled infusion catheters inserted via the right internal jugular vein

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sung Wook; Do, Young Soo; Choo, Sung Wook; Yoo, Wi Kang; Choo, In Wook [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jae Hyung [Sanggye Paik Hospital, Inje University, Seoul (Korea, Republic of)

    2003-03-01

    To assess the outcome of tunneled central venous catheter placement via the right internal jugular vein. Between June 2001 and May 2002, 670 consecutive Hickman catheters were placed in 654 patients via the right internal jugular vein. The procedural complications arising and follow-up data obtained from May to July 2002 were evaluated. The technical success rate for catheter placement was 99.9% (669/670). Procedural complications were limited to eight cases (1.2%), including three pneumothoraces, one early migration of the catheter, one clinically unimportant air embolism, one catheter injury, one catheter kinking and one primary malpositioning in the azygos vein. Catheter dwelling time ranged from 1 to 407 (mean 107.1) days. During the follow-up period, 416 catheter were removed for various reasons: treatment had ended (n=334), patients declined treatment or their drug regimen was changed (n=16), late complications arose (n=53), or other circumstances intervened (n=13). Late complications included 44 cases of catheter-related infection (6.6%), five of catheter migration (0.7%), two of catheter occlusion (0.3%), one of thrombophlebitis (0.15%), and one of catheter-related right atrial thrombosis (0.15%). Only one instance of symptomatic venous thrombosis or stenosis was noted, namely the one case of thrombophlebitis. Because the incidence of subsequent symptomatic venous thrombosis or stenosis is lower, the preferred route for tunneled central venous catheter placement is the right internal jugular vein.

  16. Placement of a Hemodialysis Catheter using the Dilated Right External Jugular Vein as a Primary Route

    Energy Technology Data Exchange (ETDEWEB)

    Park, Mi Hyun [Dankook University Hospital, Cheonan (Korea, Republic of); Shin, Byung Seok [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2010-08-15

    To evaluate the feasibility that a dilated right external jugular vein (EJV) could be a primary venous access site for large bore hemodialysis catheter placement. Between January 2008 and April 2009, a total of 173 hemodialysis catheters (14.5 F) were placed. Among them, we evaluated the clinical data of 42 patients who underwent placement through a dilated right EJV. We evaluated technical success, duration of catheterization in days, and the presence of complications. Technical success was achieved for 41 patients (98%). Catheter placement was unsuccessful in one patient due to narrowing of the EJV. The catheter dwell time ranged between 14 and 305 days (mean; 76 days, total catheter days: 3,111 days). A total of 26 hemodialysis catheters were removed due to complications (n=2) and termination of hemodialysis via the hemodialysis catheter (n=24). There was air embolization (n=1) and catheter kinking (n=3) during procedures and catheter related infections (n=2) during the follow-up period. The incidence of catheter related infection was 0.06 per 100 catheter days. No cases of catheter malfunction or symptomatic venous thrombosis were observed. We suggest that a dilated right EJV could be considered as a preferred primary route for hemodialysis catheter placement with easy access

  17. Comparison of outcomes between surgically placed and percutaneously placed peritoneal dialysis catheters: A retrospective study.

    Science.gov (United States)

    Sivaramakrishnan, R; Gupta, S; Agarwal, S K; Bhowmik, D; Mahajan, S

    2016-01-01

    There is lack of adequate data on comparison of outcomes between percutaneously placed peritoneal dialysis (PD) catheters inserted by nephrologists and PD catheters placed by surgeons. The aim of this study is to retrospectively analyze the outcomes of PD catheters inserted by surgeons (by open surgical or laparoscopic technique) and compare them with those inserted by nephrologists among ESRD patients who underwent elective PD catheter insertions between January 2009 and December 2012. The primary outcome measure was the proportion of catheters removed because of primary nonfunction. The secondary outcome measures were catheter survival, patient survival, and incidence of complications of catheter insertion. A total of 143 PD catheter insertions (88 by surgeons and 55 by nephrologists) performed in 132 patients were considered for the analysis. The primary nonfunction rate of PD catheter insertions in both groups was comparable (18.2% and 7.3%, P = 0.08). Break-in period was shorter in Group N (p = <0.001). No differences were noted in patient or catheter survival. Percutaneously placed PD catheters performed by nephrologists have comparable outcomes with surgically placed PD catheters among selected cases and have the advantage of lower costs, avoidance of operation theater scheduling issues, smaller incision length, and shorter break-in period. Therefore, more nephrologists should acquire the expertise on percutaneous PD catheter placement as it leads to lesser waiting times and better utilization of PD. PMID:27512299

  18. Needle-based confocal laser endomicroscopy

    OpenAIRE

    Giovannini, Marc

    2015-01-01

    New applications of confocal laser endomicroscopy were developed as pCLE in the bile duct and nCLE for pancreatic cystic tumors, pancreatic masses and lymph nodes. The aim of this paper would be to give you an update in this new technology and to try to define its place in the diagnosis of cystic and solid pancreatic masses. The material used was a 19G EUS-needle in which the stylet was replaced by the Confocal mini-probe. The mini-probe (0.632 mm of diameter) is pre-loaded and screwed by a l...

  19. Three-dimensional needle-tip localization by electric field potential and camera hybridization for needle electromyography exam robotic simulator.

    Science.gov (United States)

    He, Siyu; Gomez-Tames, Jose; Yu, Wenwei

    2016-01-01

    As one of neurological tests, needle electromygraphy exam (NEE) plays an important role to evaluate the conditions of nerves and muscles. Neurology interns and novice medical staff need repetitive training to improve their skills in performing the exam. However, no training systems are able to reproduce multiple pathological conditions to simulate real needle electromyogram exam. For the development of a robotic simulator, three components need to be realized: physical modeling of upper limb morphological features, position-dependent electromyogram generation, and needle localization; the latter is the focus of this study. Our idea is to couple two types of sensing mechanism in order to acquire the needle-tip position with high accuracy. One is to segment the needle from camera images and calculate its insertion point on the skin surface by a top-hat transform algorithm. The other is voltage-based depth measurement, in which a conductive tissue-like phantom was used to realize both needle-tip localization and physical sense of needle insertion. For that, a pair of electrodes was designed to generate a near-linear voltage distribution along the depth direction of the tissue-like phantom. The accuracy of the needle-tip position was investigated by the electric field potential and camera hybridization. The results showed that the needle tip could be detected with an accuracy of 1.05±0.57 mm. PMID:27382339

  20. Three-dimensional needle-tip localization by electric field potential and camera hybridization for needle electromyography exam robotic simulator

    Science.gov (United States)

    He, Siyu; Gomez-Tames, Jose; Yu, Wenwei

    2016-01-01

    As one of neurological tests, needle electromygraphy exam (NEE) plays an important role to evaluate the conditions of nerves and muscles. Neurology interns and novice medical staff need repetitive training to improve their skills in performing the exam. However, no training systems are able to reproduce multiple pathological conditions to simulate real needle electromyogram exam. For the development of a robotic simulator, three components need to be realized: physical modeling of upper limb morphological features, position-dependent electromyogram generation, and needle localization; the latter is the focus of this study. Our idea is to couple two types of sensing mechanism in order to acquire the needle-tip position with high accuracy. One is to segment the needle from camera images and calculate its insertion point on the skin surface by a top-hat transform algorithm. The other is voltage-based depth measurement, in which a conductive tissue-like phantom was used to realize both needle-tip localization and physical sense of needle insertion. For that, a pair of electrodes was designed to generate a near-linear voltage distribution along the depth direction of the tissue-like phantom. The accuracy of the needle-tip position was investigated by the electric field potential and camera hybridization. The results showed that the needle tip could be detected with an accuracy of 1.05±0.57 mm. PMID:27382339

  1. A European perspective on intravascular catheter-related infections

    DEFF Research Database (Denmark)

    Bouza, E; San Juan, R; Muñoz, P;

    2004-01-01

    The laboratory workload, microbiological techniques and aetiology of catheter-related infections in European hospitals are mostly unknown. The present study (ESGNI-005) comprised a 1-day (22 October 2001), laboratory-based, point-prevalence survey based on a questionnaire completed by microbiology...... by these institutions was 121,363,800, and the estimated number of admissions during 2000 was 6,712,050. The total number of catheter tips processed during 2000 was 142,727, or 21/1,000 admissions, of which 23.7% were considered to be positive in the institutions using semiquantitative or quantitative techniques....... Overall, EU centres received significantly more catheter tip samples/1,000 admissions and had a significantly higher rate of 'positivity' (p...

  2. The supraclavicular fossa ultrasound view for central venous catheter placement and catheter change over guidewire.

    Science.gov (United States)

    Kim, Se-Chan; Klebach, Christian; Heinze, Ingo; Hoeft, Andreas; Baumgarten, Georg; Weber, Stefan

    2014-12-23

    The supraclavicular fossa ultrasound view can be useful for central venous catheter (CVC) placement. Venipuncture of the internal jugular veins (IJV) or subclavian veins is performed with a micro-convex ultrasound probe, using a neonatal abdominal preset with a probe frequency of 10 Mhz at a depth of 10-12 cm. Following insertion of the guidewire into the vein, the probe is shifted to the right supraclavicular fossa to obtain a view of the superior vena cava (SVC), right pulmonary artery and ascending aorta. Under real-time ultrasound view, the guidewire and its J-tip is visualized and pushed forward to the lower SVC. Insertion depth is read from guidewire marks using central venous catheter. CVC is then inserted following skin and venous dilation. The supraclavicular fossa view is most suitable for right IJV CVC insertion. If other insertion sites are chosen the right supraclavicular fossa should be within the sterile field. Scanning of the IJVs, brachiocephalic veins and SVC can reveal significant thrombosis before venipuncture. Misplaced CVCs can be corrected with a change over guidewire technique under real-time ultrasound guidance. In conjunction with a diagnostic lung ultrasound scan, this technique has a potential to replace chest radiograph for confirmation of CVC tip position and exclusion of pneumothorax. Moreover, this view is of advantage in patients with a non-p-wave cardiac rhythm were an intra-cardiac electrocardiography (ECG) is not feasible for CVC tip position confirmation. Limitations of the method are lack of availability of a micro-convex probe and the need for training.

  3. Clinical efficacy and safety of catheter ablation for atrial fibrillation in elderly patients

    Institute of Scientific and Technical Information of China (English)

    董静

    2013-01-01

    Objective To evaluate the clinical efficacy and safty of catheter ablation for atrial fibrillation in elderly patients.Methods From September 2008 to October 2011,a total of 420 consecutive patients undergoing cathete rablation

  4. Evaluation of Fiber Bundle Rotation for Enhancing Gas Exchange in a Respiratory Assist Catheter

    OpenAIRE

    Eash, Heide J.; Mihelc, Kevin M.; Frankowski, Brain J.; Hattler, Brack G.; Federspiel, William J.

    2007-01-01

    Supplemental oxygenation and carbon dioxide removal through an intravenous respiratory assist catheter can be used as a means of treating patients with acute respiratory failure. We are beginning development efforts toward a new respiratory assist catheter with an insertional size

  5. Use of the Hickman catheter as permanent vascular access for hemodialysis.

    Science.gov (United States)

    Kinnaert, P; Hooghe, L; De Pauw, L; Dhaene, M; Dratwa, M; Vanherweghem, J L

    1990-01-01

    Nineteen patients in whom it was impossible to create an arteriovenous (AV) fistula were hemodialyzed with adult Hickman catheters as the sole vascular access. Catheter survival was 45% at 1 year, with eight patients requiring two or three catheters for the continuation of their treatment. The probability of a patient still being dialyzed with a Hickman catheter at 1 year was 69%. The calculated risk of developing the most frequent complications was 0.07/100 catheter days for sepsis, 0.4/100 catheter days for thrombosis, and 0.06/100 catheter days for outflow obstruction. These figures seem quite acceptable, and the use of Hickman catheters as permanent vascular access is warranted in this category of difficult patient. PMID:2340207

  6. Fluoroscopy guided percutaneous catheter drainage of pneumothorax in good mid-term patency with tube drainage

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ga Young; Oh, Joo Hyung; Yoon, Yup; Sung, Dong Wook [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1995-10-15

    To evaluate efficacy and the safety of percutaneous catheter drainage in patients with pneumothorax that is difficult to treat with closed thoracotomy. We retrospectively reviewed effectiveness of percutaneous catheter drainage (PCD) in 10 patients with pneumothorax. The catheter was inserted under fluoroscopic guidance. Seven patients had spontaneous pneumothorax caused by tuberculosis (n =4), reptured bullae (n = 2), and histiocytosis-X (n = 1). Three patients had iatrogenic pneumothorax caused by trauma (n = 1) and surgery (n = 2). All procedures were performed by modified Seldinger's method by using 8F-20F catheter. All catheter were inserted successfully. In 9 of 10 patients, the procedure was curative without further therapy. Duration of catheter insertion ranged from 1 day to 26 days. In the remaining 1 patient in whom multiple pneumothorax occurred after operation, catheter insertion was performed twice. Percutaneous catheter drainage under fluoroscopic guidance is effective and safe procedure for treatment of pneumothorax in patients with failed closed thoracotomy.

  7. Fluoroscopy guided percutaneous catheter drainage of pneumothorax in good mid-term patency with tube drainage

    International Nuclear Information System (INIS)

    To evaluate efficacy and the safety of percutaneous catheter drainage in patients with pneumothorax that is difficult to treat with closed thoracotomy. We retrospectively reviewed effectiveness of percutaneous catheter drainage (PCD) in 10 patients with pneumothorax. The catheter was inserted under fluoroscopic guidance. Seven patients had spontaneous pneumothorax caused by tuberculosis (n =4), reptured bullae (n = 2), and histiocytosis-X (n = 1). Three patients had iatrogenic pneumothorax caused by trauma (n = 1) and surgery (n = 2). All procedures were performed by modified Seldinger's method by using 8F-20F catheter. All catheter were inserted successfully. In 9 of 10 patients, the procedure was curative without further therapy. Duration of catheter insertion ranged from 1 day to 26 days. In the remaining 1 patient in whom multiple pneumothorax occurred after operation, catheter insertion was performed twice. Percutaneous catheter drainage under fluoroscopic guidance is effective and safe procedure for treatment of pneumothorax in patients with failed closed thoracotomy

  8. Evaluation of the safety of latrogenic lntestinal perforation during placement of percutaneous drainage catheter in rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Choon Hyeong; Oh, Joo Hyung; Park, Ga Young; Shin, Hong Sub; Kim, In Sub; Yoon, Yup; Lee, Dong Ho; Ko, Young Tae; Choi, Woo Suk; Lim, Joo Won [Kyunghee Univ. Hospital, Seoul (Korea, Republic of)

    1996-10-01

    To evaluate the safety of transgression of the bowel during intraperitoneal percutaneous catheter placement in an animal model. Eight 8-F straight catheters were percutaneously inserted into the small and large bowel of eight rabbits. In four animals, the catheters were left in place until autopsy, whereas in the remaining four, the catheters were withdrawn five days after insertion. Autopsy was performed in all animals ten days after catheter placement, and gross and microscopic examination was carried out. Transgressing the bowel during intraperitoneal percutaneous catheter placement did not contribute to any clinically significant complications. At autopsy, there was no bowel leakage, peritonitis, or abscess, although peritoneal adhesions were found around the catheter tract. Although further study is warranted, our study with an animal model indicated that transgression of the intestine during percutaneous placement of an intraabdominal catheter did not produce significant complications.

  9. Effect of plastic catheters on the phagocytic activity of human polymorphonuclear leukocytes.

    Science.gov (United States)

    López-López, G; Pascual, A; Perea, E J

    1990-05-01

    The effect of five kinds of plastic catheters (polyvinyl chloride, Teflon, polyurethane, Vialon and siliconized latex) on the phagocytic and bactericidal function of human polymorphonuclear leukocytes was evaluated. In the presence of the polyvinyl chloride, Teflon and siliconized latex catheters, superoxide radical production by polymorphonuclear leukocytes was significantly inhibited. The effect of the siliconized latex catheter was presumably mediated by products eluted from the catheter into the medium, since the incubation of polymorphonuclear leukocytes in eluates obtained from the incubation of this catheter in buffer induced a similar inhibitory effect. This phenomenon was not observed with polyurethane or Vialon catheters. Neither the catheters evaluated nor their eluates affected the uptake of opsonized Staphylococcus aureus by human polymorphonuclear leukocytes. It is concluded that the polyvinyl chloride, Teflon and siliconized latex catheters used in this study could impair the respiratory burst of human polymorphonuclear leukocytes. PMID:2164932

  10. Adjacent central venous catheters can result in immediate aspiration of infused drugs during renal replacement therapy.

    Science.gov (United States)

    Kam, K Y R; Mari, J M; Wigmore, T J

    2012-02-01

    Dual-lumen haemodiafiltration catheters enable continuous renal replacement therapy in the critically ill and are often co-located with central venous catheters used to infuse drugs. The extent to which infusions are immediately aspirated by an adjacent haemodiafiltration catheter remains unknown. A bench model was constructed to evaluate this effect. A central venous catheter and a haemodiafiltration catheter were inserted into a simulated central vein and flow generated using centrifugal pumps within the simulated vein and haemodiafiltration circuit. Ink was used as a visual tracer and creatinine solution as a quantifiable tracer. Tracers were completely aspirated by the haemodiafiltration catheter unless the infusion was at least 1 cm downstream to the arterial port. No tracer was aspirated from catheters infusing at least 2 cm downstream. Orientation of side ports did not affect tracer elimination. Co-location of central venous and haemodiafiltration catheters may lead to complete aspiration of infusions into the haemodiafilter with resultant drug under-dosing.

  11. Radiologic interventional retrieval of retained central venous catheter fragment in prematurity: case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jee Won; Jo, Jung Hyun; Park, Byeong Ho [College of Medicine, Dong-A University, Busan (Korea, Republic of)

    2007-12-15

    The fracture of a central venous catheter is a rare but potentially serious complication. Moreover, removal of the broken catheter pieces is considerably challenging, especially for premature infants. We report 3 case studies of the percutaneous transcatheter retrieval of broken catheter parts in 3 premature infants. We confirmed the location of the catheter fragments via a DSA venogram with diluted contrast media. Using the minimum amount of contrast, and extreme caution, we made certain no contrast-induced nephrotoxicity of air embolism occurred during catheter manipulation. In addition, when the broken fragment was curled or attached to the cardiac wall, we used a hook-shaped catheter to facilitate the capturing of the catheter with a loopsnare. This report demonstrates the feasibility of removing a retained catheter fragment in a premature infant using a percutaneous transcatheter approach.

  12. Implementation of a children's hospital-wide central venous catheter insertion and maintenance bundle

    NARCIS (Netherlands)

    K. Helder MScN (Onno); R.F. Kornelisse (René); C. van der Starre (Cynthia); D. Tibboel (Dick); C.W.N. Looman (Caspar); R.M.H. Wijnen (Rene); M.J. Poley (Marten); E. Ista (Erwin)

    2013-01-01

    textabstractBackground: Central venous catheter-associated bloodstream infections in children are an increasingly recognized serious safety problem worldwide, but are often preventable. Central venous catheter bundles have proved effective to prevent such infections. Successful implementation requir

  13. Biofilm formation in long-term central venous catheters in children with cancer

    DEFF Research Database (Denmark)

    Handrup, Mette Møller; Fuursted, Kurt; Funch, Peter;

    2012-01-01

    Taurolidine has demonstrated inhibition of biofilm formation in vitro. The aim of this study was to compare the effect of catheter locking with taurolidine vs heparin in biofilm formation in central venous catheters. Forty-eight children with cancer were randomized to catheter locking by heparin (n...... = 22) or taurolidine (n = 26), respectively. After removal, catheters were examined by standardized scanning electron microscopy to assess quantitative biofilm formation. Biofilm was present if morphologically typical structures and bacterial cells were identified. Quantitative and semi......-quantitative cultures were also performed. Biofilm was identified in 23 of 26 catheters from the taurolidine group and 21 of 22 catheters from the heparin group. A positive culture was made of six of the catheters locked with taurolidine and heparin, respectively (p = 0.78). The rate of catheter-related bloodstream...

  14. The Hunter Pulmonary Angiography Catheter for a Brachiocephalic Vein Approach

    International Nuclear Information System (INIS)

    The purpose of this work was to describe our experience in performing pulmonary angiography using the Hunter pulmonary catheter, manufactured by Cook, Inc., which is a modified 6F pigtail catheter with a 'C-shaped' curve, designed for a brachiocephalic vein approach. One hundred twenty-three patients underwent pulmonary angiograms using the Hunter catheter between August 1997 and January 2002. Operator comments were gathered in 86 (70%) of the cases. The operator was, if possible, the most junior resident on the service. Thirty-nine operators participated in the survey. Efficacy, safety, and ease of use of the catheter were determined by operators' comments and ECG observations during the procedure. Corroborating clinical data were gathered from medical records. In 68 (79%) of the procedures that were commented upon, the operator described insertion into the pulmonary artery (PA) as easy; only 2 (2%) indicated difficulty in accessing the PA. In 41 (63%) of the bilateral angiograms that were commented upon, the operator described accessing the left PA from the right PA as easy; only 6 (9%) rated it as difficult and all were with an older technique in which the catheter was withdrawn to the pulmonary bifurcation without a wire or with only the soft tip of the wire in the pigtail and then rotated to the left main pulmonary artery. Thirty-one of the 41 patients who demonstrated premature ventricular contractions (PVCs) had a previous history of heart disease. Nineteen of the 39 patients who did not have PVCs had a history of heart disease (p = 0.018). The maneuverability and shape of the Hunter catheter make pulmonary angiography an easy procedure, even for operators with minimal experience and limited technical proficiency. PVCs demonstrated a statistically significant correlation with a positive patient history for cardiac disease, rather than being a universal risk

  15. CT imaging of complications of catheter ablation for atrial fibrillation

    International Nuclear Information System (INIS)

    The complication rate following radiofrequency catheter ablation for atrial fibrillation is low (<5%). Complications include pericardial effusion, cardiac tamponade, pulmonary vein stenosis, oesophageal ulceration or perforation, atrio-oesophageal fistula formation, stroke/transient ischaemic attack, phrenic nerve injury, haematoma at the puncture site, and femoral arteriovenous fistula. Among available imaging tools, computed tomography (CT) can be very useful in diagnosing complications of the procedure, particularly in the subacute and delayed stages after ablation. This review illustrates CT imaging of several of the common and uncommon complications of radiofrequency catheter ablation

  16. The catheter hub disinfection cap as esophageal foreign body.

    Science.gov (United States)

    Tawfik, Kareem O; Myer, Charles M; Shikary, Tasneem; Goldschneider, Kenneth R

    2015-12-01

    Disinfection caps are increasingly being used to prevent catheter-associated bloodstream infections. These devices, designed for continuous passive disinfection of catheter hubs, are typically small and often brightly colored. As such, they have the potential to become pediatric airway and esophageal foreign bodies. We report two patients who developed esophageal foreign body following ingestion of disinfection caps. Given the increasing use of these devices, it is imperative that health care providers be aware of this potential iatrogenic problem. We propose that the use of disinfection caps may not be appropriate in pediatric patients with risk factors for foreign body ingestion.

  17. Spontaneous migration of central venous catheter tip following extubation

    Directory of Open Access Journals (Sweden)

    Balaji Prabaharan

    2014-01-01

    Full Text Available Migration of the tip of central venous catheters is not an uncommon event and the mechanism for this is not clear. Increased intrathoracic pressure due to coughing, sneezing or weight lifting, changing the body position or physical movements such as abduction or adduction of the arms is thought to be the cause of such migration. We present here a case of a patient with a port catheter tip that migrated from the left subclavian to the superior vene cava following extubation.

  18. Imaging of the complications of peripherally inserted central venous catheters

    Energy Technology Data Exchange (ETDEWEB)

    Amerasekera, S.S.H. [Department of Radiology, Good Hope Hospital, Sutton Coldfield, Birmingham (United Kingdom)], E-mail: steve.amerasekera@nhs.net; Jones, C.M.; Patel, R.; Cleasby, M.J. [Department of Radiology, Good Hope Hospital, Sutton Coldfield, Birmingham (United Kingdom)

    2009-08-15

    Peripherally inserted central catheters (PICC) are widely used to provide central venous access, often in chronically ill patients with long-term intravenous access requirements. There are a number of significant complications related to both insertion and maintenance of PICC lines, including catheter malposition, migration, venous thrombosis, and line fracture. The incidence of these complications is likely to rise as the number of patients undergoing intravenous outpatient therapy increases, with a corresponding rise in radiologist input. This paper provides an overview of the relevant peripheral and central venous anatomy, including anatomical variations, and outlines the complications of PICC lines. Imaging examples demonstrate the range of radiological findings seen in these complications.

  19. Colonization of bacteria on polyvinyl chloride and Teflon intravascular catheters in hospitalized patients.

    OpenAIRE

    Sheth, N. K.; Franson, T R; Rose, H. D.; Buckmire, F L; Cooper, J. A., Jr.; Sohnle, P G

    1983-01-01

    During an 8-month period all intravascular catheters were removed by sterile technique upon completion of use and submitted to the hospital microbiology laboratory. All catheters were routinely cultured by the semiquantitative culture technique, with greater than or equal to 15 colonies being defined as a positive result. Of the 687 Teflon catheters cultured, 6.9% were positive by culture, compared with 24.6% of 77 polyvinyl chloride catheters (P less than 0.001). Also, colonization of coagul...

  20. Three-dimensional needle-tip localization by electric field potential and camera hybridization for needle electromyography exam robotic simulator

    Directory of Open Access Journals (Sweden)

    He SY

    2016-06-01

    Full Text Available Siyu He,1 Jose Gomez-Tames,1 Wenwei Yu1,2 1Medical System Engineering Department, Graduate School of Engineering, 2Center for Frontier Medical Engineering, Chiba University, Chiba, Japan Abstract: As one of neurological tests, needle electromygraphy exam (NEE plays an important role to evaluate the conditions of nerves and muscles. Neurology interns and novice medical staff need repetitive training to improve their skills in performing the exam. However, no training systems are able to reproduce multiple pathological conditions to simulate real needle electromyogram exam. For the development of a robotic simulator, three components need to be realized: physical modeling of upper limb morphological features, position-dependent electromyogram generation, and needle localization; the latter is the focus of this study. Our idea is to couple two types of sensing mechanism in order to acquire the needle-tip position with high accuracy. One is to segment the needle from camera images and calculate its insertion point on the skin surface by a top-hat transform algorithm. The other is voltage-based depth measurement, in which a conductive tissue-like phantom was used to realize both needle-tip localization and physical sense of needle insertion. For that, a pair of electrodes was designed to generate a near-linear voltage distribution along the depth direction of the tissue-like phantom. The accuracy of the needle-tip position was investigated by the electric field potential and camera hybridization. The results showed that the needle tip could be detected with an accuracy of 1.05±0.57 mm. Keywords: needle-tip localization, needle EMG exam, top-hat transform, tissue-like phantom, voltage distribution simulation

  1. Laser-Controlled Growth of Needle-Shaped Organic Nanoaggregates

    DEFF Research Database (Denmark)

    Balzer, Frank; Rubahn, Horst-Günter

    2002-01-01

    Arrays of mutually parallel oriented, single-crystalline, needle-like structures of light-emitting p-hexaphenyl molecules are generated in the focus of an argon ion laser. The cross sectional dimensions of the needles are of the order of 100 to 200 nm with lengths up to several hundred micrometers...

  2. Observations on rotating needle insertions using a brachytherapy robot

    Energy Technology Data Exchange (ETDEWEB)

    Meltsner, M A [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States); Ferrier, N J [Department of Mechanical Engineering, University of Wisconsin, Madison, WI 53706 (United States); Thomadsen, B R [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2007-09-21

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  3. Observations on rotating needle insertions using a brachytherapy robot

    Science.gov (United States)

    Meltsner, M. A.; Ferrier, N. J.; Thomadsen, B. R.

    2007-09-01

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  4. Coaxial needle insertion assistant with enhanced force feedback.

    Science.gov (United States)

    De Lorenzo, Danilo; Koseki, Yoshihiko; De Momi, Elena; Chinzei, Kiyoyuki; Okamura, Allison M

    2013-02-01

    Many medical procedures involving needle insertion into soft tissues, such as anesthesia, biopsy, brachytherapy, and placement of electrodes, are performed without image guidance. In such procedures, haptic detection of changing tissue properties at different depths during needle insertion is important for needle localization and detection of subsurface structures. However, changes in tissue mechanical properties deep inside the tissue are difficult for human operators to sense, because the relatively large friction force between the needle shaft and the surrounding tissue masks the smaller tip forces. A novel robotic coaxial needle insertion assistant, which enhances operator force perception, is presented. This one-degree-of-freedom cable-driven robot provides to the operator a scaled version of the force applied by the needle tip to the tissue, using a novel design and sensors that separate the needle tip force from the shaft friction force. The ability of human operators to use the robot to detect membranes embedded in artificial soft tissue was tested under the conditions of 1) tip force and shaft force feedback, and 2) tip force only feedback. The ratio of successful to unsuccessful membrane detections was significantly higher (up to 50%) when only the needle tip force was provided to the user. PMID:23193302

  5. Co-Flow Hollow Cathode Technology

    Science.gov (United States)

    Hofer, Richard R.; Goebel, Dan M.

    2011-01-01

    Hall thrusters utilize identical hollow cathode technology as ion thrusters, yet must operate at much higher mass flow rates in order to efficiently couple to the bulk plasma discharge. Higher flow rates are necessary in order to provide enough neutral collisions to transport electrons across magnetic fields so that they can reach the discharge. This higher flow rate, however, has potential life-limiting implications for the operation of the cathode. A solution to the problem involves splitting the mass flow into the hollow cathode into two streams, the internal and external flows. The internal flow is fixed and set such that the neutral pressure in the cathode allows for a high utilization of the emitter surface area. The external flow is variable depending on the flow rate through the anode of the Hall thruster, but also has a minimum in order to suppress high-energy ion generation. In the co-flow hollow cathode, the cathode assembly is mounted on thruster centerline, inside the inner magnetic core of the thruster. An annular gas plenum is placed at the base of the cathode and propellant is fed throughout to produce an azimuthally symmetric flow of gas that evenly expands around the cathode keeper. This configuration maximizes propellant utilization and is not subject to erosion processes. External gas feeds have been considered in the past for ion thruster applications, but usually in the context of eliminating high energy ion production. This approach is adapted specifically for the Hall thruster and exploits the geometry of a Hall thruster to feed and focus the external flow without introducing significant new complexity to the thruster design.

  6. Removal of an embedded crochet needle in the mouth.

    Science.gov (United States)

    Klovenski, Victoria; Juergens, Andrew; Lappo, Kyla; Marshall, Kyle

    2016-01-01

    A 3-year-old child presented to the emergency department with a crochet needle lodged in her posterior oral cavity. To localize the needle and significant surrounding anatomic structures, bedside transcavitary ultrasound was employed. After careful localization, the needle was removed using a modified needle cover technique. A review of barbed foreign object removal techniques, including advance-and-cut, retrograde, string-yank, and needle cover techniques, is presented. Important considerations while planning any procedure include risk, benefit, availability of staff, and availability of equipment. Proper anesthesia is paramount to the success of these procedures, and sedation in pediatric patients may prove necessary. Postprocedure wound care and follow-up must also be arranged. This case demonstrates the importance of adaptation of well-documented techniques to remain flexible for any situation that may present to the emergency department.

  7. Effect of physical disturbance on the structure of needle coke

    Science.gov (United States)

    Zhao, Shi-Gui; Wang, Bao-Cheng; Sun, Quan

    2010-10-01

    Through different preparation technology, this paper reports that the needle coke is prepared with coal-tar pitch under the effect of magnetic field and ultrasonic cavitation. It studies the effect of physical disturbance on the structure of needle coke. The structure of needle coke is characterized by scanning electron microscope and x-ray diffractometer, and the influence mechanism is analysed. Results showed that the structure and property of needle coke could be effectively improved by magnetic field and ultrasonic cavitations, such as degree of order, degree of graphitization and crystallization. Comparatively speaking, the effect of magnetic field was greater. The graphitization degree of needle coke prepared under the effect of magnetic field is up to 45.35%.

  8. The New-Generation Technology for Making Petroleum Needle Coke

    Institute of Scientific and Technical Information of China (English)

    Shi Changzhi; Shen Haiping; Long Jun; Xie Changjiang

    2003-01-01

    The current technology for producing the petroleum needle coke is apt to cause overflow of feedstock from the coke drums, instability in operation of coking unit, low mechanical strength of petroleum coke, and high percentage of coke powder, leading to difficulties in improving the overall quality of needle coke. Therefore, we have developed a new technology for producing the needle coke,featuring the manipulation of temperature range in a narrow scale at high pressure coupled with feedstock alternations. This new kind of technology has been successfully applied in a 60kt/a commercial coking unit. Provided that demand for the feedstock quality is satisfied, petroleum needle coke meeting the international quality standard can be manufactured using RIPP's technology for producing petroleum needle coke.

  9. 21 CFR 878.4200 - Introduction/drainage catheter and accessories.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Introduction/drainage catheter and accessories. 878.4200 Section 878.4200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Introduction/drainage catheter and accessories. (a) Identification. An introduction/drainage catheter is...

  10. Transcatheter Removal of Embolized Port Catheters from the Hearts of Two Children

    Directory of Open Access Journals (Sweden)

    Osman Baspinar

    2015-01-01

    Full Text Available Embolization of a port catheter is a dangerous and serious complication. In this paper, we present two cases of children, aged 4.5 months and 6 years, in whom port catheters had embolized to the right ventricle one month and 1.5 years priorly, respectively; the port catheters were retrieved via snaring.

  11. Numerical simulation of the pulsating catheter pump : A left ventricular assist device

    NARCIS (Netherlands)

    Verkerke, GJ; Mihaylov, D; Geertsema, AA; Lubbers, J; Rakhorst, G

    1999-01-01

    The pulsating catheter (PUCA) pump, a left ventricular assist device, consists of a hydraulically or pneumatically driven membrane pump, extracorporeally placed and mounted to a valved catheter. The catheter is introduced into an easily accessible artery and positioned with its distal tip in the lef

  12. 21 CFR 870.4210 - Cardiopulmonary bypass vascular catheter, cannula, or tubing.

    Science.gov (United States)

    2010-04-01

    ... Devices § 870.4210 Cardiopulmonary bypass vascular catheter, cannula, or tubing. (a) Identification. A cardiopulmonary bypass vascular catheter, cannula, or tubing is a device used in cardiopulmonary surgery to... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass vascular catheter,...

  13. Use of an alteplase algorithm for the management of hemodialysis catheter dysfunction.

    Science.gov (United States)

    Abdelmoneim, Ahmed S; Miller, Lisa M; Armstrong, Sean; Sood, Manish M; Wazny, Lori; Chateau, Dan; Vercaigne, Lavern M

    2012-04-01

    Hemodialysis (HD) catheter dysfunction compromises HD adequacy and increases the cost of patient care. Repeated administration of alteplase in HD catheters typically produces only short-term benefits. The purpose of this study was to design, implement, and evaluate the efficacy of an experimental alteplase algorithm to manage HD catheter dysfunction. This was a two-part prospective nonrandomized study. Baseline data of alteplase use and catheter exchange were collected during part 1 of the study. Part 2 consisted of the alteplase algorithm implementation and repeat collection of catheter data. Rates of alteplase use and catheter exchange per 1000 catheter-days were the primary and secondary outcomes of the study. One hundred and seventy-two catheters in 131 patients were followed prospectively during the course of the study. The adjusted relative rate (RR) of alteplase use showed no significant difference between both parts of the study, adjusted RR: 1.10, 95% confidence interval (CI) (0.73-1.65). Similarly, catheter exchange rates were not significantly different over the duration of the study (1.12 vs. 1.03 per 1000 catheter-days). However, waiting time for catheter exchange increased from 20.36 ± 14 days in part 1 to 38.42 ± 28 days in part 2 (P < 0.05). The alteplase algorithm did not significantly reduce alteplase use. This may be partially explained by repeated use of alteplase in part 2, due to longer waiting times for catheter exchange procedures. PMID:22098698

  14. Central venous catheter-related infections: Risk factors and effects of glycopeptide antibiotics

    Directory of Open Access Journals (Sweden)

    Arsenijević Ljubica

    2007-01-01

    Full Text Available INTRODUCTION Central venous catheters (CVC are used in the treatment of critically ill patients. Indications for placement of CVCs include hemodynamic monitoring, administration of intravenous fluids, medications and total parenteral nutrition. MATERIAL AND METHODS We investigated risk factors and effects of glycopeptide antibiotics on the development of central venous catheter-related infections in 300 patients treated in intensive care units. A semiquntitative culture technique was used. The investigation included: age, diagnosis on admission, catheter insertion site, catheter duration, the first or next catheter and using of glycopeptide drugs. RESULTS 91 catheters (30.3% were colonised, catheter-related infection was found in 50 catheters (16.7%. Infections were more frequent in catheters inserted through the internal jugular vein than in subclavian venous catheters; they were also more frequent if duration of catheterization was longer than seven days, but less frequent in patients who received glycopeptide antibiotics. The isolated microorganism was Staphylococcus aureus. DISCUSSION According to the literature, a number of catheter-related risk factors for infections include: insertion site, type of catheter, the number of manipulations, inadequat asepsis, lumen number, type of antiseptic. The relative importance of one risk factor over another is difficult to assess, given that studies have no priority report. CONCLUSION The duration of catheterization and the insertion site were the most frequent risk factors for infection. The use of glycopeptide antibiotics during catheterization has protective effects.

  15. The Ultrasound-Only Central Venous Catheter Placement and Confirmation Procedure.

    Science.gov (United States)

    Saul, Turandot; Doctor, Michael; Kaban, Nicole L; Avitabile, Nicholas C; Siadecki, Sebastian D; Lewiss, Resa E

    2015-07-01

    The placement of a central venous catheter remains an important intervention in the care of critically ill patients in the emergency department. We propose an ultrasound-first protocol for 3 aspects of central venous catheter placement above the diaphragm: dynamic procedural guidance, evaluation for pneumothorax, and confirmation of the catheter tip location.

  16. Anti-resonant hexagram hollow core fibers.

    Science.gov (United States)

    Hayes, John R; Poletti, Francesco; Abokhamis, Mousavi S; Wheeler, Natalie V; Baddela, Naveen K; Richardson, David J

    2015-01-26

    Various simple anti-resonant, single cladding layer, hollow core fiber structures are examined. We show that the spacing between core and jacket glass and the shape of the support struts can be used to optimize confinement loss. We demonstrate the detrimental effect on confinement loss of thick nodes at the strut intersections and present a fabricated hexagram fiber that mitigates this effect in both straight and bent condition by presenting thin and radially elongated nodes. This fiber has loss comparable to published results for a first generation, multi-cladding ring, Kagome fiber with negative core curvature and has tolerable bend loss for many practical applications.

  17. Hollow-Cathode Source Generates Plasma

    Science.gov (United States)

    Deininger, W. D.; Aston, G.; Pless, L. C.

    1989-01-01

    Device generates argon, krypton, or xenon plasma via thermionic emission and electrical discharge within hollow cathode and ejects plasma into surrounding vacuum. Goes from cold start up to full operation in less than 5 s after initial application of power. Exposed to moist air between operations without significant degradation of starting and running characteristics. Plasma generated by electrical discharge in cathode barrel sustained and aided by thermionic emission from emitter tube. Emitter tube does not depend on rare-earth oxides, making it vulnerable to contamination by exposure to atmosphere. Device modified for use as source of plasma in laboratory experiments or industrial processes.

  18. Nonlinear sequential laminates reproducing hollow sphere assemblages

    Science.gov (United States)

    Idiart, Martín I.

    2007-07-01

    A special class of nonlinear porous materials with isotropic 'sequentially laminated' microstructures is found to reproduce exactly the hydrostatic behavior of 'hollow sphere assemblages'. It is then argued that this result supports the conjecture that Gurson's approximate criterion for plastic porous materials, and its viscoplastic extension of Leblond et al. (1994), may actually yield rigorous upper bounds for the hydrostatic flow stress of porous materials containing an isotropic, but otherwise arbitrary, distribution of porosity. To cite this article: M.I. Idiart, C. R. Mecanique 335 (2007).

  19. Study of Torsional Impact Problem of Orthotropic Hollow Cylinder

    Institute of Scientific and Technical Information of China (English)

    杨华凯; 郝文华; 王熙

    2004-01-01

    A simple integral transform method was presented to solve the torsional impact problem of orthotropic hollow cylinder with mixed boundary condition. The analytical solution for the torsional impact problem of the orthotropic hollow cylinder was got. Some examples were calculated and discussed.

  20. Wet spinning of asymmetric hollow fibre membranes for gas separation

    NARCIS (Netherlands)

    Hof, van 't Jacob Adriaan

    1988-01-01

    This thesis describes the spinning and characterizatin of hollow fibre membranes for gas separation. The type of fibres studied here are made by a wet spinning process. A homogeneous solution is prepared, consisting of a polymer in a suitable organic solvent, and extruded as a hollow fibre. Both the

  1. Preparation of spherical hollow alumina particles by thermal plasma

    International Nuclear Information System (INIS)

    Spherical hollow particles were prepared from solid alumina powders using DC arc thermal plasma, and then spray coating was performed with the as-prepared particles. Operating variables for the hollow particle preparation process were additional plasma gas, input power, and carrier gas flow rate. The spherical hollow alumina particles were produced in the case of using additive gas of H2 or N2, while alumina surface was hardly molten in the pure argon thermal plasma. In addition, the hollow particles were well produced in high power and low carrier gas conditions due to high melting point of alumina. Hollow structure was confirmed by focused ion beam-scanning electron microscopy analysis. Morphology and size distribution of the prepared particles that were examined by field emission-scanning electron microscopy and phase composition of the particles was characterized by X-ray diffraction. In the spray coating process, the as-prepared hollow particles showed higher deposition rate. - Highlights: ► Spherical hollow alumina powder was prepared by non-transferred DC arc plasma. ► Diatomic gasses were added in Ar plasma for high power. ► Prepared hollow alumina powder was efficient for the plasma spray coating

  2. Fabrication of Closed Hollow Bulb Obturator Using Thermoplastic Resin Material

    Directory of Open Access Journals (Sweden)

    Bidhan Shrestha

    2015-01-01

    Full Text Available Purpose. Closed hollow bulb obturators are used for the rehabilitation of postmaxillectomy patients. However, the time consuming process, complexity of fabrication, water leakage, and discoloration are notable disadvantages of this technique. This paper describes a clinical report of fabricating closed hollow bulb obturator using a single flask and one time processing method for an acquired maxillary defect. Hard thermoplastic resin sheet has been used for the fabrication of hollow bulb part of the obturator. Method. After fabrication of master cast conventionally, bulb and lid part of the defect were formed separately and joined by autopolymerizing acrylic resin to form one sized smaller hollow body. During packing procedure, the defect area was loaded with heat polymerizing acrylic resin and then previously fabricated smaller hollow body was adapted over it. The whole area was then loaded with heat cure acrylic. Further processes were carried out conventionally. Conclusion. This technique uses single flask which reduces laboratory time and makes the procedure simple. The thickness of hollow bulb can be controlled and light weight closed hollow bulb prosthesis can be fabricated. It also minimizes the disadvantages of closed hollow bulb obturator such as water leakage, bacterial infection, and discoloration.

  3. Fabrication of Closed Hollow Bulb Obturator Using Thermoplastic Resin Material.

    Science.gov (United States)

    Shrestha, Bidhan; Hughes, E Richard; Kumar Singh, Raj; Suwal, Pramita; Parajuli, Prakash Kumar; Shrestha, Pragya; Sharma, Arati; Adhikari, Galav

    2015-01-01

    Purpose. Closed hollow bulb obturators are used for the rehabilitation of postmaxillectomy patients. However, the time consuming process, complexity of fabrication, water leakage, and discoloration are notable disadvantages of this technique. This paper describes a clinical report of fabricating closed hollow bulb obturator using a single flask and one time processing method for an acquired maxillary defect. Hard thermoplastic resin sheet has been used for the fabrication of hollow bulb part of the obturator. Method. After fabrication of master cast conventionally, bulb and lid part of the defect were formed separately and joined by autopolymerizing acrylic resin to form one sized smaller hollow body. During packing procedure, the defect area was loaded with heat polymerizing acrylic resin and then previously fabricated smaller hollow body was adapted over it. The whole area was then loaded with heat cure acrylic. Further processes were carried out conventionally. Conclusion. This technique uses single flask which reduces laboratory time and makes the procedure simple. The thickness of hollow bulb can be controlled and light weight closed hollow bulb prosthesis can be fabricated. It also minimizes the disadvantages of closed hollow bulb obturator such as water leakage, bacterial infection, and discoloration.

  4. Biodegradable hollow fibres for the controlled release of hormones

    NARCIS (Netherlands)

    Eenink, M.J.D.; Feijen, J.; Olijslager, J.; Albers, J.H.M.; Rieke, J.C.; Greidanus, P.J.

    1987-01-01

    Poly(l-lactide), (PLLA), hollow fibres were prepared using a dry-wet phase inversion spinning process. The effect of several spinning parameters (i.e. bore medium flow rate, spinning dope extrusion rate, fibre take-up rate, and spinning height) on the hollow fibre dimensions is reported. The use of

  5. Aluminium multi-planar hollow section traffic sign structures

    NARCIS (Netherlands)

    Soetens, F.

    1998-01-01

    Currently, overhead highway traffic sign structures in The Netherlands are triangular space frame girders composed of circular hollow steel sections supported by two X-shaped columns consisting of rectangular hollow steel sections. However. the Dutch Ministry of Transport has initiated the developme

  6. Hollow Blocks: How to Make and Use Them.

    Science.gov (United States)

    Texas Child Care, 1993

    1993-01-01

    Provides detailed plans for the construction of 11-by-11-by-5.5-inch hollow wooden blocks that can be constructed with simple tools by child-care providers and parents. Children's play with hollow blocks, which can also be constructed half- and double-size, allows them to develop muscular coordination and assists in their social and emotional…

  7. Simple Spinning of Heterogeneous Hollow Microfibers on Chip.

    Science.gov (United States)

    Yu, Yue; Wei, Wenbo; Wang, Yaqing; Xu, Cong; Guo, Yaqiong; Qin, Jianhua

    2016-08-01

    A novel and simple chip-based microfluidic strategy is proposed for continuously controlled spinning of desirable hollow microfibers. These fabricated fiber-shaped materials exhibit extraordinary morphological and structural complexity, as well as a heterogeneous composition. The resulting specific hollow microfibers have potential applications in numerous chemical and biomedical fields.

  8. PREPARATION OF HOLLOW LATEX PARTICLES BY ALKALI-ACID TREATMENT

    Institute of Scientific and Technical Information of China (English)

    郝冬梅; 王新灵; 朱卫华; 唐小真; 刘成岑; 施凯

    2001-01-01

    Hollow polymer latex particles were prepared by seeded emulsion polymerization. A seed latex consisting of styrene (St), butyl acrylate(BA) copolymer was first prepared, and seeded terpolymerization of St-BA-MA(methacrylic acid) were then carried out in the absence of surfactant. Final latex was treated by a two-step treatment under alkaline and acidic conditions, thus, the particles with hollow structure were obtained. We discussed the effects of pH value, temperature and time in alkali and acid treatment processes on hollow structure within the polymer latex particles and amount of carboxylic group on particle surface. The results show that the hollow polymer latex particles with the largest hollow size can be obtained under a certain condition (pH12.5, 90°C, 3 h in alkali treatment stage and pH2.5, 85°C, 3 h in acid treatment stage).

  9. An Atomic Lens Using a Focusing Hollow Beam

    Institute of Scientific and Technical Information of China (English)

    夏勇; 印建平; 王育竹

    2003-01-01

    We propose a new method to generate a focused hollow laser beam by using an azimuthally distributed 2π-phase plate and a convergent thin lens, and calculate the intensity distribution of the focused hollow beam in free propagation space. The relationship between the waist w0 of the incident collimated Gaussian beam and the dark spot size of the focused hollow beam at the focal point, and the relationship between the focal length f of the thin lens and the dark spot size are studied respectively. The optical potential of the blue-detuned focused hollow beam for 85Rb atoms is calculated. Our study shows that when the larger waist w of the incident Gaussian beam and the shorter focal length f of the lens are chosen, we can obtain an extremely small dark spot size of the focused hollow beam, which can be used to form an atomic lens with a resolution of several angstroms.

  10. Hollow Casein-Based Polymeric Nanospheres for Opaque Coatings.

    Science.gov (United States)

    Zhang, Fan; Ma, Jianzhong; Xu, Qunna; Zhou, Jianhua; Simion, Demetra; Carmen, Gaidău; Wang, John; Li, Yunqi

    2016-05-11

    Casein-based hollow polymeric sphere were fabricated through emulsifier-free polymerization coupled with alkali swelling approach. Hollow structure and nanoscale size of casein-based polymeric spheres were verified by TEM, AFM, SEM, and UV-vis spectra. The as-obtained hollow spheres were proved exhibiting superior opaque characteristic. Through adjusting the structural parameters, for example, MAA usages and MAA content in seed to core, sphere film showed tunable visible-light transmittance and antiultraviolet property. The formation mechanism of casein-based hollow sphere has been discussed in depth. Worth mentioning, the resultant hollow polymeric sphere can easily form films itself at room temperature, which would open a new possibility of designing opaque coatings in several fields, such as leather, packaging, paper making, biomedical, and special indoor coating applications. PMID:27090208

  11. Effect of impeller design and spacing on gas exchange in a percutaneous respiratory assist catheter.

    Science.gov (United States)

    Jeffries, R Garrett; Frankowski, Brian J; Burgreen, Greg W; Federspiel, William J

    2014-12-01

    Providing partial respiratory assistance by removing carbon dioxide (CO2 ) can improve clinical outcomes in patients suffering from acute exacerbations of chronic obstructive pulmonary disease and acute respiratory distress syndrome. An intravenous respiratory assist device with a small (25 Fr) insertion diameter eliminates the complexity and potential complications associated with external blood circuitry and can be inserted by nonspecialized surgeons. The impeller percutaneous respiratory assist catheter (IPRAC) is a highly efficient CO2 removal device for percutaneous insertion to the vena cava via the right jugular or right femoral vein that utilizes an array of impellers rotating within a hollow-fiber membrane bundle to enhance gas exchange. The objective of this study was to evaluate the effects of new impeller designs and impeller spacing on gas exchange in the IPRAC using computational fluid dynamics (CFD) and in vitro deionized water gas exchange testing. A CFD gas exchange and flow model was developed to guide a progressive impeller design process. Six impeller blade geometries were designed and tested in vitro in an IPRAC device with 2- or 10-mm axial spacing and varying numbers of blades (2-5). The maximum CO2 removal efficiency (exchange per unit surface area) achieved was 573 ± 8 mL/min/m(2) (40.1 mL/min absolute). The gas exchange rate was found to be largely independent of blade design and number of blades for the impellers tested but increased significantly (5-10%) with reduced axial spacing allowing for additional shaft impellers (23 vs. 14). CFD gas exchange predictions were within 2-13% of experimental values and accurately predicted the relative improvement with impellers at 2- versus 10-mm axial spacing. The ability of CFD simulation to accurately forecast the effects of influential design parameters suggests it can be used to identify impeller traits that profoundly affect facilitated gas exchange. PMID:24749994

  12. Long-term evaluation of hollow screw and hollow cylinder dental implants : Clinical and radiographic results after 10 years

    NARCIS (Netherlands)

    Telleman, Gerdien; Meijer, Henny J. A.; Raghoebar, Gerry M.

    2006-01-01

    Background: In 1988, an implant manufacturer offered a new dental implant system, with a wide choice of hollow cylinder (HC) and hollow screw (HS) implants. The purpose of this retrospective study of HS and HC implants was to evaluate clinical and radiographic parameters of peri-implant tissue and t

  13. Transcervical Foley's catheter: a promising option for induction of labour

    Directory of Open Access Journals (Sweden)

    Divya Pandey

    2015-06-01

    Full Text Available We hereby report the results of a small randomized prospective study where we compared the efficiency and efficacy of transcervical extra-amniotic Foley catheter placement to intravaginal dinoprostone gel as a method of induction of labour. [Int J Reprod Contracept Obstet Gynecol 2015; 4(3.000: 933-933

  14. Complications of flow-directed balloon-tipped catheters.

    Science.gov (United States)

    Smart, F W; Husserl, F E

    1990-01-01

    Acute or short-term complications following the use of flow-directed balloon-tipped catheters are well recognized. Long-term sequelae are rarely reported. We report herein an early complication of pulmonary arterial rupture with infarction followed by the delayed development of a pulmonary arterial aneurysm.

  15. [Implantation technic and maintenance of a Hickman catheter for hemodialysis].

    Science.gov (United States)

    De Pauw, L; Cappello, M; Dhaene, M; Vanherweghem, J L; Kinnaert, P

    1990-01-01

    Description of the technique of insertion of the Hickman catheter for hemodialysis based on 110 operations. Absolute prerequisites for correct functioning are: 1) Fluoroscopic control of the localization of this device in the superior vena cava and 2) Checking if adequate flow can be obtained. PMID:2333726

  16. Minimizing Hemodialysis Catheter Dysfunction: An Ounce of Prevention

    Directory of Open Access Journals (Sweden)

    Timmy Lee

    2012-01-01

    Full Text Available The maintenance of tunneled catheter (TC patency is critical for the provision of adequate hemodialysis in patients who are TC-dependent. TC dysfunction results in the need for costly and inconvenient interventions, and reduced quality of life. Since the introduction of TCs in the late 1980s, heparin catheter lock has been the standard prophylactic regimen for the prevention of TC dysfunction. More recently, alternative catheter locking agents have emerged, and in some cases have shown to be superior to heparin lock with respect to improving TC patency and reducing TC-associated infections. These include citrate, tissue plasminogen activator, and a novel agent containing sodium citrate, methylene blue, methylparaben, and propylparaben. In addition, prophylaxis using oral anticoagulants/antiplatelet agents, including warfarin, aspirin, ticlodipine, as well as the use of modified heparin-coated catheters have also been studied for the prevention of TC dysfunction with variable results. The use of oral anticoagulants and/or antiplatelet agents as primary or secondary prevention of TC dysfunction must be weighed against their potential adverse effects, and should be individualized for each patient.

  17. 21 CFR 876.5090 - Suprapubic urological catheter and accessories.

    Science.gov (United States)

    2010-04-01

    ... with the aid of a trocar and cannula. The device is used to pass fluids to and from the urinary tract... instrument, suprapubic drainage tube, and the suprapubic cannula and trocar. (b) Classification. (1) Class II (performance standards). (2) Class I for the catheter punch instrument, nondisposable cannula and trocar,...

  18. Development of catheters for combined intravascular ultrasound and photoacoustic imaging

    Science.gov (United States)

    Karpiouk, Andrei B.; Wang, Bo; Emelianov, Stanislav Y.

    2009-02-01

    Coronary atherosclerosis is a complex disease accompanied by the development of plaques in the arterial wall. Since the vulnerability of the plaques depends on their composition, the appropriate treatment of the arteriosclerosis requires a reliable characterization of the plaques' geometry and content. The intravascular ultrasound (IVUS) imaging is capable of providing structural details of the plaques as well as some functional information. In turn, more functional information about the same plaques can be obtained from intravascular photoacoustic (IVPA) images since the optical properties of the plaque's components differ from that of their environment. The combined IVUS/IVPA imaging is capable of simultaneously detecting and differentiating the plaques, thus determining their vulnerability. The potential of combined IVUS/IVPA imaging has already been demonstrated in phantoms and ex-vivo experiments. However, for in-vivo or clinical imaging, an integrated IVUS/IVPA catheter is required. In this paper, we introduce two prototypes of integrated IVUS/IVPA catheters for in-vivo imaging based on a commercially available single-element IVUS imaging catheter. The light delivery systems are developed using multimode optical fibers with custom-designed distal tips. Both prototypes were tested and compared using an arterial mimicking phantom. The advantages and limitations of both designs are discussed. Overall, the results of our studies suggest that both designs of integrated IVUS/IVPA catheter have a potential for in-vivo IVPA/IVUS imaging of atherosclerotic plaques.

  19. Optimizing safety and efficacy of catheter ablation procedures

    NARCIS (Netherlands)

    F. Akca (Ferdi)

    2015-01-01

    markdownabstractAbstract In this thesis new developments in the field of invasive electrophysiology are studied and discussed. The aim of this work is to find strategies to optimize safety and efficacy of catheter ablation procedures. The most important developments that are studied in this thesis

  20. Abnormal location of umbilical venous catheter due to Scimitar syndrome

    International Nuclear Information System (INIS)

    Scimitar syndrome is a rare congenital anomaly where the right pulmonary veins return to the inferior vena cava (IVC) just below the diaphragm. On chest X-ray (CXR), an IVC catheter will be in a bizarre location outside the heart if it inadvertently passes into the scimitar vein rather than into the right atrium

  1. Peritoneo-vulvar catheter extrusion after shunt operation.

    Science.gov (United States)

    Nagulic, M; Djordjevic, M; Samardzic, M

    1996-04-01

    We report an unusual case of catheter extrusion through the external genitalia. between the labium majus and the labium minus, in a 6-month-old hydrocephalic baby. The event occurred 5 months after placement of a ventriculoperitoneal shunt. PMID:8739410

  2. Antibiofilm Activity of Electrical Current in a Catheter Model.

    Science.gov (United States)

    Voegele, Paul; Badiola, Jon; Schmidt-Malan, Suzannah M; Karau, Melissa J; Greenwood-Quaintance, Kerryl E; Mandrekar, Jayawant N; Patel, Robin

    2016-03-01

    Catheter-associated infections are difficult to treat with available antimicrobial agents because of their biofilm etiology. We examined the effect of low-amperage direct electrical current (DC) exposure on established bacterial and fungal biofilms in a novel experimental in vitro catheter model. Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida parapsilosis biofilms were grown on the inside surfaces of polyvinyl chloride (PVC) catheters, after which 0, 100, 200, or 500 μA of DC was delivered via intraluminally placed platinum electrodes. Catheter biofilms and intraluminal fluid were quantitatively cultured after 24 h and 4 days of DC exposure. Time- and dose-dependent biofilm killing was observed with all amperages and durations of DC administration. Twenty-four hours of 500 μA of DC sterilized the intraluminal fluid for all bacterial species studied; no viable bacteria were detected after treatment of S. epidermidis and S. aureus biofilms with 500 μA of DC for 4 days. PMID:26711752

  3. Hemodynamics of Central Venous Catheters: experiments and simulations

    Science.gov (United States)

    Barbour, Michael; McGah, Patrick; Clark, Alicia; Ng, Chin Hei; Gow, Kenneth; Aliseda, Alberto

    2013-11-01

    Central venous catheters (CVC) are used to provide vascular access during hemodialysis in patients with end-stage kidney disease. Despite several advantages and widespread use, CVCs have a high incidence rate of clot formation during the interdialytic phase (48 hrs). In an attempt the prevent clot formation, hospitals routinely administer heparin, an anticoagulant, into the catheter after a dialysis session. It has been reported, however, that up to 40% of the heparin solution will leak into the blood stream during the interdialytic phase, placing the patient at risk for systemic bleeding incidences. The aim of this study is to determine the role that advective-diffusive transport plays in the heparin leaking process. Numerical simulations of heparin convective mass transfer have been conducted, showing that while advective losses may be significant at the tip, previous studies may be overestimating the total amount of heparin leakage. To validate the quantitative prediction from the simulations, P.L.I.F. is used to experimentally measure heparin transport from CVCs placed in an idealized Superior Vena Cava with physically accurate pulsatile flow conditions. Improved understanding of flow near the catheter tip is applied to improve catheter design and heparin locking procedures.

  4. Percutaneous placement of peritoneal port-catheter in oncologic patients

    International Nuclear Information System (INIS)

    The aim of this paper is to describe the technique of percutaneous ultrasound (US)-guided placement of a peritoneal port-catheter in an interventional radiological setting. Nineteen patients with peritoneal carcinomatosis were selected for intraperitoneal port-catheter placement in order to perform intracavitary receptor-immuno- or radio-immunotherapy with Ytrium-90. All the procedures were performed percutaneously under US and fluoro guidance; the insertion site for catheters was chosen according to abdominal conditions and US findings: all devices were implanted at the lower abdominal quadrants. All patients were followed up with CT and US according to the therapy protocol. The procedure was successfully completed in 15/19 patients, in 4 being contraindicated by peritoneal adhesions. No procedure-related complications and device occlusions during therapy were observed; one catheter displaced 7 months later the placement. In our experience, this procedure was feasible, reliable and easy to perform, allowing the correct administration of the planned intracavitary therapy. Peritoneal adhesions are the main limitation of peritoneal port placement. (orig.)

  5. 21 CFR 876.5130 - Urological catheter and accessories.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Urological catheter and accessories. 876.5130 Section 876.5130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5130...

  6. Metal-Matrix/Hollow-Ceramic-Sphere Composites

    Science.gov (United States)

    Baker, Dean M.

    2011-01-01

    A family of metal/ceramic composite materials has been developed that are relatively inexpensive, lightweight alternatives to structural materials that are typified by beryllium, aluminum, and graphite/epoxy composites. These metal/ceramic composites were originally intended to replace beryllium (which is toxic and expensive) as a structural material for lightweight mirrors for aerospace applications. These materials also have potential utility in automotive and many other terrestrial applications in which there are requirements for lightweight materials that have high strengths and other tailorable properties as described below. The ceramic component of a material in this family consists of hollow ceramic spheres that have been formulated to be lightweight (0.5 g/cm3) and have high crush strength [40.80 ksi (.276.552 MPa)]. The hollow spheres are coated with a metal to enhance a specific performance . such as shielding against radiation (cosmic rays or x rays) or against electromagnetic interference at radio and lower frequencies, or a material to reduce the coefficient of thermal expansion (CTE) of the final composite material, and/or materials to mitigate any mismatch between the spheres and the matrix metal. Because of the high crush strength of the spheres, the initial composite workpiece can be forged or extruded into a high-strength part. The total time taken in processing from the raw ingredients to a finished part is typically 10 to 14 days depending on machining required.

  7. Hollow Pollen Shells to Enhance Drug Delivery

    Directory of Open Access Journals (Sweden)

    Alberto Diego-Taboada

    2014-03-01

    Full Text Available Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine, made largely of cellulose, and the outer layer (exine, composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet protection to the material inside it. These microcapsule shells have many advantageous properties, such as homogeneity in size, resilience to both alkalis and acids, and the ability to withstand temperatures up to 250 °C. These hollow microcapsules have the ability to encapsulate and release actives in a controlled manner. Their mucoadhesion to intestinal tissues may contribute to the extended contact of the sporopollenin with the intestinal mucosa leading to an increased efficiency of delivery of nutraceuticals and drugs. The hollow microcapsules can be filled with a solution of the active or active in a liquid form by simply mixing both together, and in some cases operating a vacuum. The active payload can be released in the human body depending on pressure on the microcapsule, solubility and/or pH factors. Active release can be controlled by adding a coating on the shell, or co-encapsulation with the active inside the shell.

  8. [Design of acupoint electric characteristic sensing needle].

    Science.gov (United States)

    Liu, Tang-yi; Yang, Hua-yuan; Kuai, Le; Gao, Ming

    2007-09-01

    The electric characteristics of acupoints have been confirmed by researchers at home and abroad. Because the traditional detection methods are various (mainly are different positions of the reference electrode), and they are influenced by many affective factors, with unstable results and bad repeatability, so the studies of the electric characteristics of acupoints are limited. The acupoint electric characteristic sensing needle is introduced in detail from its design, detection methods and so on, which can detects changes of the acupoint electric characteristics of channels and acupoints in different healthy states real-timely, dynamically and continuously. It not only can avoid those affective factors, and also the detective results are relatively stable and the repeatability is also better.

  9. Pulmonary actinomycosis in fine needle aspiration cytology

    Directory of Open Access Journals (Sweden)

    Patel Keyuri

    2009-01-01

    Full Text Available Pulmonary actinomycosis is a rare bacterial lung disease caused by one of two types of bacteria, Actinomyces or Propioni. Pulmonary actinomycosis in the lung causes lung cavities, lung nodules, and pleural effusion. We report here a case of pulmonary actinomycosis that was diagnosed by fine needle aspiration cytology (FNAC. A 45 year-old male with a history of smoking and alcohol abuse, presented with complaints of cough with hemoptysis, right-sided chest pain, and fever of two months′ duration. A chest radiograph and computed tomography (CT of the thorax showed a right upper lobe mass lesion with hilar lymphadenopathy. CT-guided FNAC revealed colonies of Actinomyces surrounded by polymorphs. The disease is commonly confused with other chronic suppurative lung diseases and malignancy. An early diagnosis by FNAC prevents difficulties in the management of the disease, as well as considerable physiological and physical morbidity, including unwarranted surgery.

  10. Transurethral microwave needle ablation for bladder cancer

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@To investigate the role of transurethral microwave needle ablation (TUMWNA) in the management of bladder cancer,TUMWNA was carried out in 24 patients with bladder cancer since 1989. From January 1989 to December 1997, 24 patients with bladder cancer were treated with TUMWNA. The 15 men and 9 women were 42 to 67 years old (mean, 58). There were 18 cases with a single tumor and 6 with multiple tumors (4 with 2 tumors, 1 with 3 and 1 with 4). Tumor diameter ranged from 0.3 to 2.5 cm. The lesions grew in different bladder regions: 13 tumors arose from the fundus, 3 tumors from the dome, 9 from the lateral wall, 5 from the anterior wall, 1 from the triangle region and 2 tumors were situated in the obturator nerve reflex sensitive region.

  11. Fine-needle aspiration cytology in fibromatoses.

    Science.gov (United States)

    Zaharopoulos, P; Wong, J Y

    1992-01-01

    Fine-needle aspiration (FNA) cytology was performed in seven cases of fibromatosis of variable types with tumorous clinical presentation. These included: four cases of musculoaponeurotic fibromatosis, two in posterior neck muscles, one in anterior neck muscles and one in intercostal muscles; one case of fibromatosis of the breast; and two cases of fibromatosis colli in neonates. In all cases the specimens contained connective tissue with many fibroblast-like cells, lacking features which could indicate a malignant lesion. The findings in these cases indicate that, although by FNA cytology in fibromatoses a specific diagnosis for each pathologic entity may not be easily reached, in the proper clinical setting the cytologic findings can be of sufficient relevance to offset the need for an open tissue biopsy, where there are valid reasons against a surgical intervention.

  12. Needle steering for robot-assisted insertion into soft tissue: A survey

    Science.gov (United States)

    Gao, Dedong; Lei, Yong; Zheng, Haojun

    2012-07-01

    Needle insertion is a common surgical procedure used in diagnosis and treatment. The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on needle insertion. It is necessary to summarize and analyze the existing results to promote the future development of theories and applications of needle insertion. Thus, a survey of the state of the art of research is presented on algorithms of needle steering techniques, the surgical robots and devices. Based on the analysis of the needle insertion procedure, the concept of needle steering is defined as a kinematics problem, which is to place the needle at the target and avoid the obstacles. The needle steering techniques, including the artificial potential field method and the nonholonomic model, are introduced to control the needles for improving the accuracy. Based on the quasi-static thinking, the virtual spring model and the cantilever-beam model are developed to calculate the amount of needle deflection and generate the needle path. The phantoms instead of the real tissue are used to verify the models mentioned in most of the experimentations. For the desired needle trajectories, the image-guided robotic devices and some novel needles are presented to achieve the needle steering. Finally, the challenges are provided involving the controllability of the long flexible needle and the properties of soft tissue. The results and investigations can be used for further study on the precision and accuracy of needle insertion.

  13. Air Separation Using Hollow Fiber Membranes

    Science.gov (United States)

    Huang, Stephen E.

    2004-01-01

    The NASA Glenn Research Center in partnership with the Ohio Aerospace Institute provides internship programs for high school and college students in the areas of science, engineering, professional administrative, and other technical areas. During the summer of 2004, I worked with Dr. Clarence T. Chang at NASA Glenn Research Center s combustion branch on air separation using hollow fiber membrane technology. . In light of the accident of Trans World Airline s flight 800, FAA has mandated that a suitable solution be created to prevent the ignition of fuel tanks in aircrafts. In order for any type of fuel to ignite, three important things are needed: fuel vapor, oxygen, and an energy source. Two different ways to make fuel tanks less likely to ignite are reformulating the fuel to obtain a lower vapor pressure for the fuel and or using an On Board Inert Gas Generating System (OBIGGS) to inert the Central Wing Tank. goal is to accomplish the mission, which means that the Air Separation Module (ASM) tends to be bulky and heavy. The primary goal for commercial aviation companies is to transport as much as they can with the least amount of cost and fuel per person, therefore the ASM must be compact and light as possible. The plan is to take bleed air from the aircraft s engines to pass air through a filter first to remove particulates and then pass the air through the ASM containing hollow fiber membranes. In the lab, there will be a heating element provided to simulate the temperature of the bleed air that will be entering the ASM and analysis of the separated air will be analyzed by a Gas Chromatograph/Mass Spectrometer (GC/MS). The GUMS will separate the different compounds in the exit streams of the ASM and provide information on the performance of hollow fiber membranes. Hopefully I can develop ways to improve efficiency of the ASM. different types of jet fuel were analyzed and data was well represented on SAE Paper 982485. Data consisted of the concentrations of over

  14. Adequate histologic sectioning of prostate needle biopsies.

    Science.gov (United States)

    Bostwick, David G; Kahane, Hillel

    2013-08-01

    No standard method exists for sampling prostate needle biopsies, although most reports claim to embed 3 cores per block and obtain 3 slices from each block. This study was undertaken to determine the extent of histologic sectioning necessary for optimal examination of prostate biopsies. We prospectively compared the impact on cancer yield of submitting 1 biopsy core per cassette (biopsies from January 2010) with 3 cores per cassette (biopsies from August 2010) from a large national reference laboratory. Between 6 and 12 slices were obtained with the former 1-core method, resulting in 3 to 6 slices being placed on each of 2 slides; for the latter 3-core method, a limit of 6 slices was obtained, resulting in 3 slices being place on each of 2 slides. A total of 6708 sets of 12 to 18 core biopsies were studied, including 3509 biopsy sets from the 1-biopsy-core-per-cassette group (January 2010) and 3199 biopsy sets from the 3-biopsy-cores-percassette group (August 2010). The yield of diagnoses was classified as benign, atypical small acinar proliferation, high-grade prostatic intraepithelial neoplasia, and cancer and was similar with the 2 methods: 46.2%, 8.2%, 4.5%, and 41.1% and 46.7%, 6.3%, 4.4%, and 42.6%, respectively (P = .02). Submission of 1 core or 3 cores per cassette had no effect on the yield of atypical small acinar proliferation, prostatic intraepithelial neoplasia, or cancer in prostate needle biopsies. Consequently, we recommend submission of 3 cores per cassette to minimize labor and cost of processing. PMID:23764163

  15. Catheter selection for ablation of the cavotricuspid isthmus for treatment of typical atrial flutter.

    Science.gov (United States)

    Da Costa, Antoine; Jamon, Yann; Romeyer-Bouchard, Cécile; Thévenin, Jérôme; Messier, Marc; Isaaz, Karl

    2006-11-01

    Radiofrequency catheter ablation (RFA) represents the first line therapy of the cavotricuspid isthmus-dependent atrial flutter (CTI-AFL) with a high efficacy and low secondary effects. RFA of CTI-dependent AFL can be performed by using various types of ablation catheters. Recent evaluations comparing externally cooled tip RFA (ecRFA) catheters and large-tip (8 mm) catheters have revealed that these catheters have a higher efficacy for CTI-AFL ablation compared to 4-mm catheters. The reliability of RFA catheters for AFL is variable and an optimal catheter selection may enhance the RFA effectiveness. The main goal of this article is to review the elements that improve the management of CTI RFA. Preliminary examinations of histopathologic and anatomical elements that may interfere with conventional CTI RFA are presented. Experimental studies concerning the electrobiology of large-tip and cooled-tip catheters are compared. The different catheter designs between cooled-tip and 8-mm-tip catheters are examined (size of the deflectable curve, rotation stability, and size of the distal nonsteerable catheter part) because of their critical role in CTI RFA results. A thorough review of clinical trials of each catheter is presented, and comparison of both catheters in this clinical setting is analyzed. In addition, the role of CTI morphology on AFL RF duration is underlined such as the value of right atrial angiography as an adjunct tool for CTI RFA catheter selection. Based on randomized studies, 8-mm-tip catheters seem to be more effective for ablation in case of straight angiographic isthmus morphology. On the other hand, ecRFA catheters appear to be more effective in cases of complex CTI anatomy or difficult CTI RFA. To reduce X-ray exposition and RFA application time, few studies report that CTI angiographic evaluation before RFA allows a catheter selection based on both CTI morphology and length. Moreover, preliminary data of randomized studies showed that an

  16. Efficacy of dicloxacillin-coated polyurethane catheters in preventing subcutaneous Staphylococcus aureus infection in mice.

    OpenAIRE

    Sherertz, R J; Forman, D M; Solomon, D D

    1989-01-01

    In a mouse model, dicloxacillin-coated polyurethane catheters or control (uncoated) catheters were placed subcutaneously and then Staphylococcus aureus was inoculated at the time of insertion, 24 or 48 h later. The in vivo half-life of the antibiotic was 11 to 16 h. When 10(5) CFU of S. aureus were inoculated at the time of catheter insertion, dicloxacillin-coated catheters kept the number of S. aureus removed from catheters by sonication below 10(2) CFU at 12, 24, 48, and 96 h after inoculat...

  17. Implanted central venous catheter-related acute superior vena cava syndrome: management by metallic stent and endovascular repositioning of the catheter tip

    Energy Technology Data Exchange (ETDEWEB)

    Qanadli, S.D.; Mesurolle, B.; Sissakian, J.F.; Chagnon, S.; Lacombe, P. [Service de Radiologie, Hopital Ambroise Pare, 92 - Boulogne (France)

    2000-08-01

    We describe a case of a 49-year-old woman with stage-IIIB lung adenocarcinoma who experienced an acute superior vena cava syndrome related to an implanted central venous catheter without associated venous thrombosis. The catheter was surgically implanted for chemotherapy. Superior vena cava syndrome appeared after the procedure and was due to insertion of the catheter through a subclinical stenosis of the superior vena cava. Complete resolution of the patient's symptoms was obtained using stent placement and endovascular repositioning of the catheter tip. (orig.)

  18. In vivo Monitoring of Serotonin by Nanomaterial Functionalized Acupuncture Needle

    Science.gov (United States)

    Li, Yu-Tao; Tang, Li-Na; Ning, Yong; Shu, Qing; Liang, Feng-Xia; Wang, Hua; Zhang, Guo-Jun

    2016-06-01

    Acupuncture treatment is amazing but controversial. Up to now, the mechanism of treating diseases by acupuncture and moxibustion is still unclear, especially the occurrence of the molecular events in local acupoints. Herein, we report an extremely stable microsensor by modifying carbon nanotube (CNT) to the tip surface of acupuncture needle and applying this CNT-modified acupuncture needle for real time monitoring of serotonin (5-HT) in vivo. To stabilize CNT modification on the needle tip surface, poly(3,4-ethylenedioxythiophene)(PEDOT) was employed as glue water to stick CNT on the needle. The detection limit of the CNT-modified needle was found to be approximately 50 nM and 78 nM in the PBS and the cell medium, respectively. In addition, the needle showed good selectivity to some inflammatory mediators and some electroactive molecules. For the first time, the CNT-modified needle could be directly probed into rat body for real time monitoring of 5-HT in vivo, showing a great potential for better understanding the mechanism of acupuncture treatment.

  19. Comparison of the clinical effects between catheter exchange methods in geriatric patients with tunneled cuffed hemodialysis catheters

    Institute of Scientific and Technical Information of China (English)

    周参新

    2012-01-01

    Objective To compare the infection-free and overall survival between first and subsequent tunneled cuffed hemodialysis catheters in geriatric patients. Methods The study involved 57 geriatric patients [32 male,25 female; mean age(72.4±6.7) years]undergoing maintenance hemodialysis in our blood

  20. Comparison of NHSN-defined central venous catheter day counts with a method that accounts for concurrent catheters.

    Science.gov (United States)

    Talbot, Thomas R; Johnson, James G; Anders, Theodore; Hayes, Rachel M

    2015-01-01

    Central venous catheter (CVC) day definitions do not consider concurrent CVCs. We examined traditional CVC day counts and resultant central line-associated bloodstream infection (CLABSI) rates with a CVC day definition that included concurrent CVCs. Accounting for concurrent CVCs increased device day counts by 8.5% but only mildly impacted CLABSI rates.

  1. Controlled trial of a continuous irrigation suction catheter vs conventional intermittent suction catheter in clearing bronchial secretions from ventilated patients.

    Science.gov (United States)

    Isea, J O; Poyant, D; O'Donnell, C; Faling, L J; Karlinsky, J; Celli, B R

    1993-04-01

    Continuous irrigation-suction catheter (Irri-cath) is a double-lumen device that allows for simultaneous saline solution infusion and aspiration. This system may theoretically be more effective than conventional dry intermittent suction due to its vortex principle. To test this hypothesis, we performed 200 suction maneuvers in 20 ventilated patients. Identically shaped catheters were used in a randomized sequence. For the same individual, we used equal instilled saline solution volume (40 ml), vacuum pressure (-180 cm H2O), and ventilatory parameters. Effectiveness of suction was determined by measuring the total aspirated volume, the dry lyophilized weight of secretion, the corrected dry weight (dry weight-weight of instilled salt), and protein concentration. No difference in heart rate, respiratory frequency, O2 saturation, systemic blood pressure, peak inspiratory pressure, or patient discomfort was found when the two modalities were compared; however, the total volume of secretions collected, the dry weight, the corrected dry weight, and the protein concentration were significantly higher with continuous irrigation suction catheter when compared with the conventional method (p < 0.05). The suction time was shorter with the Irri-cath (p < 0.05). We conclude that the Irri-Cath is more effective than conventional intermittent suction catheter in clearing bronchial secretions in patients on mechanical ventilation. PMID:8131470

  2. Comparison of a new aspiration needle device and the Quick-Core biopsy needle for transjugular liver biopsy

    Institute of Scientific and Technical Information of China (English)

    Toru Ishikawa; Tomoteru Kamimura; Hiroteru Kamimura; Atsunori Tsuchiya; Tadayuki Togashi; Kouji Watanabe; Kei-ichi Seki; Hironobu Ohta; Toshiaki Yoshida; Noriko Ishihara

    2006-01-01

    AIM: To evaluate sample adequacy, safety, and needle passes of a new biopsy needle device compared to the Quick-Core biopsy needle for transjugular liver biopsy in patients affected by liver disease.METHODS: Thirty consecutive liver-disease patients who had major coagulation abnormalities and/or relevant ascites underwent transjugular liver biopsy using either a new needle device (18 patients) or the Quick-Core biopsy needle (12 patients). The length of the specimens was measured before fixation. A pathologist reviewed the histological slides for sample adequacy and pathologic diagnoses. The two methods' specimen adequacy and complication rates were assessed.RESULTS: Liver biopsies were technically successful in all 30 (100%) patients, with diagnostic histological core specimens obtained in 30 of 30 (100%) patients, for an overall success rate of 100%. With the new device,18 specimens were obtained, with an average of 1.1passes per patient. Using the Quick-Core biopsy needle,12 specimens were obtained, with an average of 1.8passes per patient. Specimen length was significantly longer with the new needle device than with the QuickCore biopsy needle (P < 0.05). The biopsy tissue was not fragmented in any of the specimens with the new aspiration needle device, but tissue was fragmented in 3 of 12 (25.0%) specimens obtained using the Quick-Core biopsy needle. Complications included cardiac arrhythmia in 3 (10.0%) patients, and transient abdominal pain in 4 (13.3%) patients. There were no cases of subcapsular hematoma, hemoperitoneum, or sepsis, and there was no death secondary to the procedure. In particular, no early or delayed major procedure-related complications were observed in any patient.CONCLUSION: Transjugular liver biopsy is a safe and effective procedure, and there was significant difference in the adequacy of the specimens obtained using the new needle device compared to the QuickCore biopsy needle. Using the new biopsy needle device,the specimens showed

  3. Flushing and Locking of Venous Catheters: Available Evidence and Evidence Deficit

    Directory of Open Access Journals (Sweden)

    Godelieve Alice Goossens

    2015-01-01

    Full Text Available Flushing and locking of intravenous catheters are thought to be essential in the prevention of occlusion. The clinical sign of an occlusion is catheter malfunction and flushing is strongly recommended to ensure a well-functioning catheter. Therefore fluid dynamics, flushing techniques, and sufficient flushing volumes are important matters in adequate flushing in all catheter types. If a catheter is not in use, it is locked. For years, it has been thought that the catheter has to be filled with an anticoagulant to prevent catheter occlusion. Heparin has played a key role in locking venous catheters. However, the high number of risks associated with heparin forces us to look for alternatives. A long time ago, 0.9% sodium chloride was already introduced as locking solution in peripheral cannulas. More recently, a 0.9% sodium chloride lock has also been investigated in other types of catheters. Thrombolytic agents have also been studied as a locking solution because their antithrombotic effect was suggested as superior to heparin. Other catheter lock solutions focus on the anti-infective properties of the locks such as antibiotics and chelating agents. Still, the most effective locking solution will depend on the catheter type and the patient’s condition.

  4. Chlorhexidine Gluconate Dressings Reduce Bacterial Colonization Rates in Epidural and Peripheral Regional Catheters

    Directory of Open Access Journals (Sweden)

    Klaus Kerwat

    2015-01-01

    Full Text Available Introduction. Bacterial colonization of catheter tips is common in regional anesthesia and is a suspected risk factor for infectious complications. This is the first study evaluating the effect of CHG-impregnated dressings on bacterial colonization of regional anesthesia catheters in a routine clinical setting. Methods. In this prospective study, regional anesthesia catheter infection rates were examined in two groups of patients with epidural and peripheral regional catheters. In the first group, regional anesthesia was dressed with a conventional draping. The second group of patients underwent catheter dressing using a CHG-impregnated draping. Removed catheters and the insertion sites were both screened for bacterial colonization. Results. A total of 337 catheters from 308 patients were analysed. There was no significant reduction of local infections in either epidural or peripheral regional anesthesia catheters in both CHG and conventional groups. In the conventional group, 21% of the catheter tips and 41% of the insertion sites showed positive culture results. In the CHG-group, however, only 3% of the catheter tips and 8% of the insertion sites were colonised. Conclusion. CHG dressings significantly reduce bacterial colonization of the tip and the insertion site of epidural and peripheral regional catheters. However, no reductions in rates of local infections were seen.

  5. Dialysis catheter-related septicaemia--focus on Staphylococcus aureus septicaemia

    DEFF Research Database (Denmark)

    Nielsen, J; Ladefoged, S D; Kolmos, H J

    1998-01-01

    BACKGROUND: Dialysis catheters are a common cause of nosocomial septicaemia in haemodialysis units usually due to staphylococci, of which Staphylococcus aureus is the most pathogenic. In this study, the epidemiology and pathogenesis of dialysis catheter-related infections were studied, and methods...... to identify patients with these infections were evaluated. METHODS: A one-year prospective study of 67 catheters in 43 haemodialysis patients was performed. Details about patients and catheters were obtained successively during the catheter period, and biochemical parameters expected to be related...... to infection were measured. After catheter insertion, all patients were screened for nasal carriage of S. aureus, and a culture was taken from the skin overlying the catheter insertion site. Once a week, cultures were taken from the insertion site and from the hub, and aerobic and anaerobic blood cultures were...

  6. The selection of small forest hollows for pollen analysis in boreal and temperate forest regions

    DEFF Research Database (Denmark)

    Overballe-Petersen, Mette V; Bradshaw, Richard H.W.

    2011-01-01

    Small forest hollows represent a specialised site type for pollen analysis, since they mainly record the vegetation within an approximate radius of 20-100 m from the hollow. We discuss how to choose the most appropriate small forest hollow for pollen analysis. Hollow size, site topography, location...

  7. A New Flavonoid in Pine Needles of Cedrus deodara

    Institute of Scientific and Technical Information of China (English)

    LIU Dong-yan; SHI Xiao-feng; WANG Dong-dong; MA Qu-huan; ZHANG Jun-min; LI Chong

    2011-01-01

    Objective To study the chemical constituents of flavonoids in pine needles of Cedrus deodara.Methods Flavonoids were isolated and purified from ethyl acetate extract of pine needles by chromatography on silica gel and Sephadex LH-20.Their structures were identified on the basis of spectroscopic analysis and chemical evidence.Results Five flavonoids were isolated and purified.Their structures were identified as cedrusone A(1),myricetin(2),2R,3R-dihydromyricetin(3),quercctin(4),and 2R,3R-dihydroquercetin(5).Conclusion Compound 1 is a new compound.Compounds 2-5 are isolated from pine needles of this genus for the first time.

  8. Why should we use atraumatic needles in lumbar puncture?

    Directory of Open Access Journals (Sweden)

    Sandro Luiz de Andrade Matas

    2013-09-01

    Full Text Available Diagnostic lumbar puncture is essential to the diagnosis of central nervous system infections, subarachnoid haemorrhage and others neurological diseases. Myeloradicular involvement or life-threatening adverse events due to the procedure are rare, but less severe complications are more frequent. Post-lumbar puncture headache is the most common complication, by spinal fluid leakage due to delayed closure of a dural defect. Therefore, the development of fine needles, with differentiated atraumatic bevel, has contributed to minimize that problem. These generically called atraumatic needles cause less deformation of the dura mater then the Quincke® ones. So, why don't we use these atraumatic needles?

  9. Diagenesis of conifer needles in a coastal marine environment

    Science.gov (United States)

    Hedges, John I.; Weliky, K.

    1989-10-01

    Physically intact fir, hemlock and cedar needles were isolated from different horizons of a sediment core from a coastal marine bay (Dabob Bay, Washington State, U.S.A.) and from nearby trees and forest litter. Green fir, hemlock and cedar needles were all characterized by glucose-rich aldose mixtures (~30% of tissue carbon), the production of vanillyl and cinnamyl CuO-derived phenols (~8% of tissue carbon) and the presence of both pinitol and myo-inositol (1-2% of tissue carbon). Needles from forest litter were enriched in lignin phenols and non-glucose aldoses and depleted in glucose and cyclitols. The sediment core contained an average of 10 mg/1 of physically intact fir, hemlock and cedar needles, which occurred in similar relative abundances and accounted for less than 1% of the total nonwoody gymnosperm tissue. Compared to the green and litter counterparts, all sedimentary needles were greatly depleted in cyclitols, glucose and p-coumaric acid and enriched in vanillyl phenol precursors. The degree of elevation of vanillyl phenol yield from the degraded needles was used to estimate minimal carbon losses from the samples, which ranged from near 40% for needle litter to almost 70% for the deepest (~100 years old) sedimentary fir/hemlock samples. Although downcore increases in carbon loss and refractory organic components indicated in situ diagenesis, the bulk of overall degradation occurred either on land or during the first 10-20 years after deposition. Atomic C/N ratios of degraded needles were lower than for green counterparts, but nitrogen was lost overall. These relative changes indicate the following stability series: vanillyl phenols > N > ferulic acid, p-hydroxy phenols, most aldoses and bulk tissue > glucose and p-coumaric acid > cyclitols (near 100% loss). Vanillic acid to vanillin ratios, (Ad/Al)v, of the green fir and hemlock needles were unusually high (0.36-0.38) and decreased downcore. Diagenesis also decreased the cinnamyl/vanillyl phenol ratio

  10. On the use of hypodermic needles in electrospray

    Directory of Open Access Journals (Sweden)

    Gañán-Calvo A.M.

    2013-04-01

    Full Text Available We present an experimental analysis of electrospray where the standard feeding capillary was re- placed with a hypodermic needle. Both the current intensity and the jet diameter were measured for a variety of leaky-dielectric liquids. The results obtained with a feeding capillary and a hypodermic needle of similar dimen- sions were compared. An increase of the liquid conductivity was measured by assuming that the electric current obeys the same scaling law in both configurations. That increase was likely due to the electrochemical reaction taking place in the needle tip.

  11. Boron nitride hollow nanospheres: Synthesis, formation mechanism and dielectric property

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, B.; Tang, X.H. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Huang, X.X., E-mail: swliza@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Xia, L. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Zhang, X.D. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wang, C.J. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Wen, G.W., E-mail: g.wen@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2015-04-15

    Highlights: • BN hollow nanospheres are fabricated in large scale via a new CVD method. • Morphology and structure are elucidated by complementary analytical techniques. • Formation mechanism is proposed based on experimental observations. • Dielectric properties are investigated in the X-band microwave frequencies. • BN hollow nanospheres show lower dielectric loss than regular BN powders. - Abstract: Boron nitride (BN) hollow nanospheres have been successfully fabricated by pyrolyzing vapors decomposed from ammonia borane (NH{sub 3}BH{sub 3}) at 1300 °C. The final products have been extensively characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The BN hollow nanospheres were ranging from 100 to 300 nm in diameter and around 30–100 nm in thickness. The internal structure of the products was found dependent on the reaction temperatures. A possible formation mechanism of the BN hollow nanospheres was proposed on the basis of the experimental observations. Dielectric measurements in the X-band microwave frequencies (8–12 GHz) showed that the dielectric loss of the paraffin filled by the BN hollow nanospheres was lower than that filled by regular BN powders, which indicated that the BN hollow nanospheres could be potentially used as low-density fillers for microwave radomes.

  12. Energy efficient engine shroudless, hollow fan blade technology report

    Science.gov (United States)

    Michael, C. J.

    1981-01-01

    The Shroudless, Hollow Fan Blade Technology program was structured to support the design, fabrication, and subsequent evaluation of advanced hollow and shroudless blades for the Energy Efficient Engine fan component. Rockwell International was initially selected to produce hollow airfoil specimens employing the superplastic forming/diffusion bonding (SPF/DB) fabrication technique. Rockwell demonstrated that a titanium hollow structure could be fabricated utilizing SPF/DB manufacturing methods. However, some problems such as sharp internal cavity radii and unsatisfactory secondary bonding of the edge and root details prevented production of the required quantity of fatigue test specimens. Subsequently, TRW was selected to (1) produce hollow airfoil test specimens utilizing a laminate-core/hot isostatic press/diffusion bond approach, and (2) manufacture full-size hollow prototype fan blades utilizing the technology that evolved from the specimen fabrication effort. TRW established elements of blade design and defined laminate-core/hot isostatic press/diffusion bonding fabrication techniques to produce test specimens. This fabrication technology was utilized to produce full size hollow fan blades in which the HIP'ed parts were cambered/twisted/isothermally forged, finish machined, and delivered to Pratt & Whitney Aircraft and NASA for further evaluation.

  13. Improved Rare-Earth Emitter Hollow Cathode

    Science.gov (United States)

    Goebel, Dan M.

    2011-01-01

    An improvement has been made to the design of the hollow cathode geometry that was created for the rare-earth electron emitter described in Compact Rare Earth Emitter Hollow Cathode (NPO-44923), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 52. The original interior assembly was made entirely of graphite in order to be compatible with the LaB6 material, which cannot be touched by metals during operation due to boron diffusion causing embrittlement issues in high-temperature refractory materials. Also, the graphite tube was difficult to machine and was subject to vibration-induced fracturing. This innovation replaces the graphite tube with one made out of refractory metal that is relatively easy to manufacture. The cathode support tube is made of molybdenum or molybdenum-rhenium. This material is easily gun-bored to near the tolerances required, and finish machined with steps at each end that capture the orifice plate and the mounting flange. This provides the manufacturability and robustness needed for flight applications, and eliminates the need for expensive e-beam welding used in prior cathodes. The LaB6 insert is protected from direct contact with the refractory metal tube by thin, graphite sleeves in a cup-arrangement around the ends of the insert. The sleeves, insert, and orifice plate are held in place by a ceramic spacer and tungsten spring inserted inside the tube. To heat the cathode, an insulating tube is slipped around the refractory metal hollow tube, which can be made of high-temperature materials like boron nitride or aluminum nitride. A screw-shaped slot, or series of slots, is machined in the outside of the ceramic tube to constrain a refractory metal wire wound inside the slot that is used as the heater. The screw slot can hold a single heater wire that is then connected to the front of the cathode tube by tack-welding to complete the electrical circuit, or it can be a double slot that takes a bifilar wound heater with both leads coming out

  14. Use of open-ended Foley catheter to treat profuse urine leakage around suprapubic catheter in a female patient with spina bifida who had undergone closure of urethra and suprapubic cystostomy: a case report

    OpenAIRE

    Vaidyanathan, Subramanian; Soni, Bakul M.; Peter L. Hughes; Singh, Gurpreet

    2009-01-01

    Introduction Leakage of urine around a catheter is not uncommon in spinal cord injury patients, who have indwelling urethral catheter. Aetiological factors for leakage of urine around a catheter are bladder spasms, partial blockage of catheter, constipation, and urine infection. Usually, leakage of urine subsides when the underlying cause is treated. Leakage of urine around a suprapubic catheter is very rare and occurs in patients, in whom the urethra is closed due to severe stricture or prev...

  15. Observations of three-dimensional needle deflection during insertion into soft tissue

    NARCIS (Netherlands)

    Jahya, Alex; Heijden, van der Ferdinand; Misra, Sarthak

    2012-01-01

    Accurate needle placement is important during percutaneous needle insertion procedures such as biopsy and brachytherapy. However, needle-tissue interactions may cause the needle to deviate from its intended path. In this paper, we have investigated the effects of insertion velocity, tip bevel angle

  16. A NOVEL METHOD TO PREPARE CROSSLINKED POLYETHYLENEIMINE HOLLOW NANOSPHERES

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel method to prepare crosslinked polyethyleneimine (CPEI) hollow nanospheres was reported.Uniform silica nanospheres were used as templates,3-aminopropyl trimethoxysilane (APS) was immobilized on the surface of silica nanospheres as couple agent.Aziridine was initiated ring-opening polymerization with the amino groups in APS to form polyethyleneimine (PEI) shell layer.1,4-Butanediol diacrylate was utilized to crosslink PEI polymeric shell.The silica nanospheres in core were etched by hydrofluoric acid to obtain hollow CPEI nanospheres.The hollow nanospheres were characterized by X-ray photoelectron spectroscopy (XPS),transmission electron microscopy (TEM),and thermogravimetric analysis (TGA).

  17. Hollow Gaussian Schell-model beam and its propagation

    CERN Document Server

    Wang, Li-Gang

    2007-01-01

    In this paper, we present a new model, hollow Gaussian-Schell model beams (HGSMBs), to describe the practical dark hollow beams. An analytical propagation formula for HGSMBs passing through a paraxial first-order optical system is derived based on the theory of coherence. Based on the derived formula, an application example showing the influence of spatial coherence on the propagation of beams is illustrated. It is found that the beam propagating properties of HGSMBs will be greatly affected by their spatial coherence. Our model provides a very convenient way for analyzing the propagation properties of partially coherent dark hollow beams.

  18. Formation of hollow nanocrystals through the nanoscale kirkendall effect

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Yadong; Rioux, Robert M.; Erdonmez, Can K.; Hughes, Steven; Somorjai, Gabor A.; Alivisatos, A. Paul

    2004-03-11

    We demonstrate that hollow nanocrystals can be synthesized through a mechanism analogous to the Kirkendall Effect, in which pores form due to the difference in diffusion rates between two components in a diffusion couple. Cobalt nanocrystals are chosen as a primary example to show that their reaction in solution with oxygen, sulfur or selenium leads to the formation of hollow nanocrystals of the resulting oxide and chalcogenides. This process provides a general route to the synthesis of hollow nanostructures of large numbers of compounds. A simple extension of this process yields platinum-cobalt oxide yolk-shell nanostructures which may serve as nanoscale reactors in catalytic applications.

  19. Development of hollow electron beams for proton and ion collimation

    CERN Document Server

    Stancari, G.; Kuznetsov, G.; Shiltsev, V.; Still, D.A.; Valishev, A.; Vorobiev, L.G.; Assmann, R.; Kabantsev, A.

    2010-01-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams

  20. Hollow Electron Beam Collimator: R&D Status Report

    CERN Document Server

    Stancari, G; Kuznetsov, G; Shiltsev, V; Valishev, A; Kabantsev, A; Vorobiev, L

    2012-01-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

  1. Development of hollow electron beams for proton and ion collimation

    CERN Document Server

    Stancari, G; Kuznetsov, G; Shiltsev, V; Still, D A; Valishev, A; Vorobiev, L G; Assmann, R; Kabantsev, A

    2012-01-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

  2. Hollow fiber membranes and methods for forming same

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Dhaval Ajit; McCloskey, Patrick Joseph; Howson, Paul Edward; Narang, Kristi Jean; Koros, William

    2016-03-22

    The invention provides improved hollow fiber membranes having at least two layers, and methods for forming the same. The methods include co-extruding a first composition, a second composition, and a third composition to form a dual layer hollow fiber membrane. The first composition includes a glassy polymer; the second composition includes a polysiloxane; and the third composition includes a bore fluid. The dual layer hollow fiber membranes include a first layer and a second layer, the first layer being a porous layer which includes the glassy polymer of the first composition, and the second layer being a polysiloxane layer which includes the polysiloxane of the second composition.

  3. New cobweb-structure hollow Bragg optical fibers

    Institute of Scientific and Technical Information of China (English)

    YU Rong-jin; ZHANG Yong-qiang; ZHANG Bing; WANG Chao-ran; WU Chang-qi

    2007-01-01

    A new type of Bragg fibers,i.e. hollow-core cobweb-structured optical fibers,which can be used to the low-loss transmission from visible to near infrared region (0.65 μm-1.55 μm),terahertz wave (200 μm-480 μm) and circular-polarization-maintaining single-mode transmission are investigated. Results show that the hollow-core cobweb-structured fibers have less loss than other hollow-core Bragg fibers. The fibers can be constituted by using the plastics or glasses with large absorption losses.

  4. Axisymmetric Vibration of Piezo-Lemv Composite Hollow Multilayer Cylinder

    Directory of Open Access Journals (Sweden)

    E. S. Nehru

    2012-01-01

    Full Text Available Axisymmetric vibration of an infinite piezolaminated multilayer hollow cylinder made of piezoelectric layers of 6 mm class and an isotropic LEMV (Linear Elastic Materials with Voids layers is studied. The frequency equations are obtained for the traction free outer surface with continuity conditions at the interfaces. Numerical results are carried out for the inner, middle, and outer hollow piezoelectric layers bonded by LEMV (It is hypothetical material layers and the dispersion curves are compared with that of a similar 3-layer model and of 3 and 5 layer models with inner, middle, and outer hollow piezoelectric layers bonded by CFRP (Carbon fiber reinforced plastics.

  5. Risk factors for the appearance of central venous catheters colonization

    Directory of Open Access Journals (Sweden)

    Mioljević Vesna

    2007-01-01

    Full Text Available Introduction/Aim. Intravascular device placement (IVD is a part of everyday medical practice, however, its application is associated with a high risk of onset of nosocomial infections (NI and increased mortality and morbidity. Nosocomial blood infections (NBIs account for 10% of all the registered NI. NBIs are more frequent in patients with a placed IVD and it present an important risk factor for the onset of NBI, i.e. catheter-associated NBIs (CANBIs. Pathogenesis of CANBIs is complex and conditioned by the presence of different characteristics related to a catheter, patient and a specific causative organism. The most common CRBSI causes include coagulase-negative staphylococcus, S. aureus, Enterobacter spp, Candida spp, Klebsiella spp, Pseudomonas spp. and Enterococcus spp. Methods. All the patients hospitalized at the Intensive Care Department of the Clinic of Digestive Diseases over the period January 1, 2004-September 1, 2004 were retrospectively analyzed. The study included 107 patients in whom central venous catheter (CVC was placed for more than 48 h. All the causes isolated from a CVC segment were recorded. Culture, isolation and identification of the causative organisms were performed using standard microbiological methods in the Bacteriological Laboratory within the Emergency Center, Clinical Center of Serbia. Catheter segment samples (tip of the CVC 3-5 cm long were analyzed. Based on the insight into medical documentation, patients’ examination and medical staff interview, catheter and patient-related characteristics were recorded. Results. A total of 107 CVCs were analyzed, out of which 56 (52% were sterile while 51 (48% were colonized. The results of our study evidenced that total parenteral nutrition (TPN (p < 0.05, number of catheterization days (p < 0.05, and central venous pressure measurement (p < 0.05 were significantly associated with CVC colonization. In this study, no statistically significant difference in catheter

  6. Hollow micro string based calorimeter device

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a micron-scale calorimeter and a calorimetry method utilizing the micron-scale calorimeter. In accordance with the invention, there is provided a micron-scale calorimeter comprising a micro-channel string, being restrained at at least two longitudinally distanced...... positions so as to form a free released double clamped string in-between said two longitudinally distanced positions said micro-channel string comprising a microfluidic channel having a closed cross section and extending in the longitudinal direction of the hollow string, acoustical means adapted to...... oscillate the string at different frequencies by emitting sound waves towards the string, optical means adapted to detect oscillating frequencies of the string, and controlling means controlling the strength and frequency of the sound wave emitted by the acoustical means and receiving a signal from the...

  7. Dual-core antiresonant hollow core fibers.

    Science.gov (United States)

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters. PMID:27464191

  8. Dual-core antiresonant hollow core fibers.

    Science.gov (United States)

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters.

  9. Chalcogenide glass hollow core photonic crystal fibers

    Science.gov (United States)

    Désévédavy, Frédéric; Renversez, Gilles; Troles, Johann; Houizot, Patrick; Brilland, Laurent; Vasilief, Ion; Coulombier, Quentin; Traynor, Nicholas; Smektala, Frédéric; Adam, Jean-Luc

    2010-09-01

    We report the first hollow core photonic crystal fibers (HC PCF) in chalcogenide glass. To design the required HC PCF profiles for such high index glass, we use both band diagram analysis to define the required photonic bandgap and numerical simulations of finite size HC PCFs to compute the guiding losses. The material losses have also been taken into account to compute the overall losses of the HC PCF profiles. These fibers were fabricated by the stack and draw technique from TeAsSe (TAS) glass. The fibers we drew in this work are composed of six rings of holes and regular microstructures. Two profiles are presented, one is known as a kagome lattice and the other one corresponds to a triangular lattice. Geometrical parameters are compared to the expected parameters obtained by computation. Applications of such fibers include power delivery or fiber sensors among others.

  10. Nonparaxial Dark-Hollow Gaussian Beams

    Institute of Scientific and Technical Information of China (English)

    GAO Zeng-Hui; L(U) Bai-Da

    2006-01-01

    The concept of nonparaxial dark-hollow Gaussian beams (DHGBs) is introduced. By using the Rayleigh-Sommerfeld diffraction integral, the analytical propagation equation of DHGBs in free space is derived. The on-axis intensity, far-field equation and, in particular, paraxial expressions are given and treated as special cases of our result. It is shown that the parameter f = 1/kw0 with k being the wave number and w0 being the waist width determines the nonparaxiality of DHGBs. However, the parameter range, within which the paraxial approach is valid, depends on the propagation distance. The beam order affects the beam profile and position of maximum on-axis intensity.

  11. Permeability of Hollow Microspherical Membranes to Helium

    Science.gov (United States)

    Zinoviev, V. N.; Kazanin, I. V.; Pak, A. Yu.; Vereshchagin, A. S.; Lebiga, V. A.; Fomin, V. M.

    2016-01-01

    This work is devoted to the study of the sorption characteristics of various hollow microspherical membranes to reveal particles most suitable for application in the membrane-sorption technologies of helium extraction from a natural gas. The permeability of the investigated sorbents to helium and their impermeability to air and methane are shown experimentally. The sorption-desorption dependences of the studied sorbents have been obtained, from which the parameters of their specific permeability to helium are calculated. It has been established that the physicochemical modification of the original particles exerts a great influence on the coefficient of the permeability of a sorbent to helium. Specially treated cenospheres have displayed high efficiency as membranes for selective extraction of helium.

  12. Two-piece hollow bulb obturator

    Directory of Open Access Journals (Sweden)

    Subramaniam Elangovan

    2011-01-01

    Full Text Available There are various types of obturator fabrication achievable by prosthodontist. Maxillectomy, which is a term used by head and neck surgeons and prosthodontists to describe the partial or total removal of the maxilla in patients suffering from benign or malignant neoplasms is a defect for which to provide an effective obturator is a difficult task for the maxillofacial prosthodontist. Multidisciplinary treatment planning is essential to achieve adequate retention and function for the prosthesis. Speech is often unintelligible as a result of the marked defects in articulation and nasal resonance. This paper describes how to achieve the goal for esthetics and phonetics and also describes the fabrication of a hollow obturator by two piece method, which is simple and maybe used as definitive obturator for maximum comfort of the patient.

  13. THEORETICAL ANALYSIS ON THE DEPTH OF NEEDLE-INSERTION

    Institute of Scientific and Technical Information of China (English)

    LIN Wen-jian

    2005-01-01

    In the present paper, the author sums up and analyzes descriptions about needle-insertion depth in Chinese classical medical book Huang Di Nei Jing (The Yellow Emperor's Internal Classic). In many chapters of Nei Jing, the needle-insertion depth is stressed to be various according to 1) the deficiency or excess of syndromes, 2) the patients' constitution, 3) the severity of disease, 4) the duration of disease, 5) the location of disease, 6) the patient's age, 7) the location of the needled acupoint, 8) the season, 9) the patient's temperament, 10) the pulse condition, 11) the state of "Deqi", and 12) the location of the running course of meridians. In addition, different kinds of diseases and different stages of diseases also need different depths of needle insertion, different manipulating skills and different stimulating quantity.

  14. Should fine needle aspiration cytology in breast assessment be abandoned?

    Energy Technology Data Exchange (ETDEWEB)

    Litherland, Janet C

    2002-02-01

    Fine needle aspiration cytology (FNAC) has been used extensively in the U.K. for the diagnosis of breast lesions over the past 15 years. More recently, large gauge needle biopsy has been used to address many of the problems which have been encountered with fine needle aspiration. This paper reviews the evolution of the use of these procedures and the advantages and disadvantages of each. In considering whether to abandon the use of fine needle aspiration cytology in breast assessment, each individual unit should make a decision based upon their own audited results. However, even if FNAC is retained, it is important to be able to complement cytological diagnosis with core biopsy as there are indisputable advantages, e.g. in the diagnosis of mammographically detected microcalcification. As always, a multi-disciplinary approach is ultimately essential for effective patient management. Litherland, J.C. (2002)

  15. Should fine needle aspiration cytology in breast assessment be abandoned?

    Science.gov (United States)

    Litherland, Janet C

    2002-02-01

    Fine needle aspiration cytology (FNAC) has been used extensively in the U.K. for the diagnosis of breast lesions over the past 15 years. More recently, large gauge needle biopsy has been used to address many of the problems which have been encountered with fine needle aspiration. This paper reviews the evolution of the use of these procedures and the advantages and disadvantages of each. In considering whether to abandon the use of fine needle aspiration cytology in breast assessment, each individual unit should make a decision based upon their own audited results. However, even if FNAC is retained, it is important to be able to complement cytological diagnosis with core biopsy as there are indisputable advantages, e.g. in the diagnosis of mammographically detected microcalcification. As always, a multi-disciplinary approach is ultimately essential for effective patient management. PMID:11977938

  16. Warm-Needling Technique for Peripheral Facial Paralysis

    Institute of Scientific and Technical Information of China (English)

    WANG Chuan-nian; ZHOU Jing; SHAO Ming-hai

    2007-01-01

    Objective: To observe the therapeutic effects of warm-needling technique on peripheral facial paralysis. Methods: Warm-needling technique and electroacupuncture were employed to treat 30 cases of facial paralysis, respectively. The same acupoints, Cuanzhu(BL 2)towards Yuyao(Ex-HN 4), Yingxiang(LI 20) towards Xiaguan(ST 7), Taiyang(Ex-HN 5)towards Xuanlu(GB 5), Dicang(ST 4) towards Jiache(ST 6), and Chengjiang(CV 24) towards Daying(ST 5), were used. Results: After 33 treatments, the warm-needling technique has an effective rate of 83.3%, while the electroacupuncture 67.7%. Conclusion: The therapeutic effect of warm-needling technique was better than that of electroacupuncture method.

  17. NEEDLE ANATOMY CHANGES WITH INCREASING TREE AGE IN DOUGLAS FIR

    Science.gov (United States)

    Morphological differences between old growth and sapling (Pseudotsuga menziesii, (Mirb.) Franco) Douglas fir trees may extend to differences in needle anatomy. We used microscopy with image analysis to compare and quantify anatomical parameters in cross-sections of previous year...

  18. [Doctor HUANG Shi-ping's acupuncture with golden needles].

    Science.gov (United States)

    Chen, Teng-Fei; Ma, Zeng-Bin; Xin, Si-Yuan; Zhu, Jiang

    2013-08-01

    Taking Doctor HUANG Shi-ping as the representative, the school of Huang's golden needle is based on Chinese martial art. Golden needles are adopted as main tool. Attaching great importance on the combination of acupuncture and moxibustioin, it is also characterized with penetrating needling with long needles. Through the development of three generations, it once outshone other schools in the field of acupuncture, and became famous all over the world. It made great contribution to the development of the course of acupuncture. However, with the development of the history, the form of acupuncture education as well as apparatus were all undergone an unified reform. Therefore, Doctor HUANG Shi-ping's acupuncture school be lost gradually.

  19. [Infection of a hip prosthesis after dry needling].

    Science.gov (United States)

    Steentjes, Koen; de Vries, Lieke M A; Ridwan, Ben U; Wijgman, A J Jurgen

    2016-01-01

    A 57-year-old patient presented to the orthopaedic department with hip pain 7 months after hip replacement and two weeks after dry needling by a physiotherapist. Dry needling is used by physiotherapists to treat pain and stiffness. In the Netherlands, there are no clear guidelines or contra-indications described for this treatment. The surgical scar of our patient showed signs of inflammation for which debridement and irrigation were performed. Tissue samples showed positive bacterial cultures and the patient was treated with antibiotics. One week after completing this treatment, the infection returned. Debridement and irrigation were repeated and antibiotic treatment was recommenced. Three months later, the patient showed no signs of infection with the prosthesis still in situ. Although there is no strong evidence for a causal relationship between dry needling and the infection, dry needling should be used carefully in patients with a joint replacement, due to the increased risk of infection. PMID:26786794

  20. Ralph L. Huber, DMD: forgotten inventor of the "Tuohy" needle.

    Science.gov (United States)

    Lubisich, Josef W

    2004-07-01

    The hypodermic needle popularized by Edward Tuohy, MD for use in his method of continuous spinal anesthesia has been incorrectly called the "Tuohy needle" since he first popularized it in 1945. It was recently determined that Ralph L. Huber, a Seattle dentist, was the inventor of this widely used needle. However, very little is known about Huber. There is no mention of him in the medical literature, and until recently, he was forgotten. Through the location of various primary sources, including the original needle point invented by Dr. Huber, this essay introduces the fascinating life of Dr. Huber, and also his personal notes about his inventions. Not only was he a prominent Seattle dentist, but also a prolific inventor.

  1. Housing shortages in urban regions: aggressive interactions at tree hollows in forest remnants.

    Science.gov (United States)

    Davis, Adrian; Major, Richard E; Taylor, Charlotte E

    2013-01-01

    Urbanisation typically results in a reduction of hollow-bearing trees and an increase in the density of particularly species, potentially resulting in an increased level of competition as cavity-nesting species compete for a limited resource. To improve understanding of hollow usage between urban cavity-nesting species in Australia, particularly parrots, we investigated how the hollow-using assemblage, visitation rate, diversity and number of interactions varied between hollows within urban remnant forest and continuous forest. Motion-activated video cameras were installed, via roped access to the canopy, and hollow usage was monitored at 61 hollows over a two-year period. Tree hollows within urban remnants had a significantly different assemblage of visitors to those in continuous forest as well as a higher rate of visitation than hollows within continuous forest, with the rainbow lorikeet making significantly more visitations than any other taxa. Hollows within urban remnants were characterised by significantly higher usage rates and significantly more aggressive interactions than hollows within continuous forest, with parrots responsible for almost all interactions. Within urban remnants, high rates of hollow visitation and both interspecific and intraspecific interactions observed at tree hollows suggest the number of available optimal hollows may be limiting. Understanding the usage of urban remnant hollows by wildlife, as well as the role of parrots as a potential flagship for the conservation of tree-hollows, is vital to prevent a decrease in the diversity of urban fauna, particularly as other less competitive species risk being outcompeted by abundant native species.

  2. Evaluation of Efficacy of Four Laparoscopic Needle Drivers

    OpenAIRE

    Ramani, Anup P.; Braasch, Matthew; Botnaru, Andrei; Lavers, Ann; Herrera, Shannon; Pedro, Renato Nardi; Monga, Manoj

    2008-01-01

    Introduction: To evaluate the impact of needle driver design on laparoscopic suturing skills by experts and novices. Methods: Three experienced laparoscopic surgeons and 3 novice junior residents were asked to perform a fixed set of suturing tasks in a laparoscopic pelvic-trainer. The laparoscopic needle drivers compared were (1) the Ethicon driver (E 705R), (2) Karl Storz (KS) pistol grip (26173 KC), (3) KS finger grip (26167 SK), and (4) KS palm grip (26173 ML). Times were recorded for each...

  3. Fine Needle Aspiration Cytology of Pediatric Thyroid Nodules

    OpenAIRE

    Ayper KAÇAR; İrem PAKER; Gülşah KABAÇAM BAYRAM; Fatma DEMİREL; Şenel, Emrah; Murat KIZILGÜN

    2010-01-01

    Objective: The objectives were to evaluate fine needle aspiration cytology results of 39 pediatric patients, and the pathologies that cause childhood thyroid nodules, and to review the literature on the subject.Material and Method: Thyroid fine needle aspiration cytology results of 39 pediatric patients were retrospectively reviewed. Associated diseases, thyroid functions, anti-thyroid antibody levels, ultrasonographic findings and number of nodules were also evaluated.Results: The vast major...

  4. Enterobacter aerogenes Needle Stick Leads to Improved Biological Management System

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, Richard E.

    2004-08-01

    A laboratory worker who received a needle stick from a contaminated needle while working with a culture containing Enterobactor aerogenes developed a laboratory acquired infection. Although this organism has been shown to cause community and nosocomial infections, there have been no documented cases of a laboratory acquired infections. Lessons learned from the event led to corrective actions which included modification of lab procedures, development of a biological inventory tracking and risk identification system and the establishment of an effective biological safety program.

  5. A Needle Penetrating the Stomach Cavity after Acupuncture

    OpenAIRE

    Lee, Sin Won; Ahn, Ji Yong; Choi, Won Jung; Kim, Eun Jin; Bae, Seung-Hyeon; Choi, Yun Sik; Jung, Hwoon-Yong; Kim, Jin-Ho

    2014-01-01

    Although acupuncture is known as a safe procedure that is widely used in many countries, complications including infection, hemorrhage, hematoma, pneumothorax, nerve damage, and cardiac tamponade have been reported. A needle penetrating the stomach after acupuncture, however, is very rare. Here, we report the case of 47-year-old woman who experienced abdominal pain 2 days after receiving acupuncture. Upper gastrointestinal endoscopy identified an approximately 2.5-cm long needle in the poster...

  6. Clinical Application of Movement-needling Technique: Stiff Neck

    Institute of Scientific and Technical Information of China (English)

    LIU Yan

    2005-01-01

    @@ Movement-needling Technique, a new acupuncture therapy, is based on traditional acupuncture therapy and anatomical principle, combining acupuncture and movement. Combining disease and syndrome differentiation, and integrating TCM and Western medical diagnosis, this technique is used to treat different diseases mainly with acupuncture,combining some movement in needling. These movements not only boost therapeutic effects of acupuncture, but also add new contents to traditional acupuncture.

  7. ImaGiNe-S: Imaging Guided Needle Simulation

    OpenAIRE

    Bello, Fernando; Bulpitt, Andrew; Gould, Derek A.; Holbrey, Richard; Hunt, Carrie; How, Thien; John, Nigel W; Johnson, Sheena; Phillips, Roger; Sinha, Amrita; Vidal, Franck P; Villard, Pierre-Frédéric; Woolnough, Helen; Zhang, Yan

    2009-01-01

    We present an integrated system for training visceral needle puncture procedures. Our aim is to provide a cost effective and validated training tool that uses actual patient data to enable interventional radiology trainees to learn how to carry out image-guided needle puncture. The input data required is a computed tomography scan of the patient that is used to create the patient specific models. Force measurements have been made on real tissue and the resulting data is incorporated into the ...

  8. Developing An Immersive Ultrasound Guided Needle Puncture Simulator

    OpenAIRE

    Vidal, Franck P; Villard, Pierre-Frederic; Holbrey, Richard; John, Nigel W; Bello, Fernando; Bulpitt, Andrew; Gould, Derek A.

    2009-01-01

    We present an integrated system for training ultrasound guided needle puncture. Our aim is to provide a cost effective and validated training tool that uses actual patient data to enable interventional radiology trainees to learn how to carry out image-guided needle puncture. The input data required is a computed tomography scan of the patient that is used to create the patient specific models. Force measurements have been made on real tissue and the resulting data is incorporated into the si...

  9. Endoscopic and endosonography guided fine-needle aspiration.

    Science.gov (United States)

    Antillon, M R; Chang, K J

    2000-10-01

    Endoscopic ultrasound-guided fine-needle aspiration is emerging as the preferred technique for the cytologic diagnosis of various gastrointestinal lesions. This technique may not be routinely available, but there is still a role for endoscopic or endoscopic ultrasound-assisted fine-needle aspiration. This article provides an overview of the evolution of these various techniques and discusses the advantages, disadvantages, indications, and contraindications of each. PMID:11036536

  10. Usefulness and safety of the GuideLiner catheter to enhance intubation and support of guide catheters: insights from the Twente GuideLiner registry

    NARCIS (Netherlands)

    Man, de F.H.; Birgelen, von C.; et al,

    2012-01-01

    Aims: Optimal ostial seating and adequate back-up of guide catheters are required for challenging percutaneous coronary interventions (PCI). The GuideLiner™ (GL) (Vascular Solutions Inc., Minneapolis, MN, USA) is a guide catheter extension system that provides active back-up support by deep coronary

  11. Verification of pulmonary vein isolation during single transseptal cryoballoon ablation: a comparison between the classical circular mapping catheter and the inner lumen mapping catheter

    NARCIS (Netherlands)

    Chierchia, G.B.; Namdar, M.; Sarkozy, A.; Sorgente, A.; Asmundis, C. de; Casado-Arroyo, R.; Capulzini, L.; Bayrak, F.; Rodriguez-Manero, M.; Ricciardi, D.; Rao, J.Y.; Overeinder, I.; Paparella, G.; Brugada, P.

    2012-01-01

    AIMS: Cryoballoon ablation has proven very effective in achieving pulmonary vein isolation (PVI). The novel Achieve inner lumen mapping catheter designed to be used in conjunction with the cryoballoon, serves as both a guidewire and a mapping catheter. To our knowledge, this is the first study compa

  12. Sonication for diagnosis of catheter-related infection is not better than traditional roll-plate culture: a prospective cohort study with 975 central venous catheters.

    Science.gov (United States)

    Erb, Stefan; Frei, Reno; Schregenberger, Katharina; Dangel, Marc; Nogarth, Danica; Widmer, Andreas F

    2014-08-15

    This prospective randomized controlled study with 975 nontunneled central venous catheters (CVCs) showed that the semiquantitative roll-plate culture technique (SQC) was as accurate as the sonication method for diagnosis of catheter-related infections. Sonication is difficult to standardize, whereas SQC is simpler, faster, and as reliable as the sonication method for culturing CVCs.

  13. Correction of malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Ryong; Baek, Kyong Hee; Jung, Gyoo Sik; Huh, Jin Do; Joh, Young Duk; Rim, Hark [Kosin Medical College, Pusan (Korea, Republic of)

    1997-11-01

    To determine the efficacy of correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance. Between November 1994 and March 1997, we performed 15 manipulations in 12 patients in whom a dual-cuff, straight Tenckhoff peritoneal dialysis catheter had been implanted due to chronic renal failure. The causes of catheter malfunctioning were inadequate drainage of the dialysate(n=14) and painful dialysis(n=1). Under fluoroscopic guidance, adhesiolysis and repositioning of the malfunctioning catheter were performed with an Amplatz Super Stiff guidewire and the stiffener from a biliary drainage catheter. The results of procedures were categorized as either immediate or durable success, this latter being defined as adequate catheter function for at least one month after the procedure. Immediate success was achieved in 14 of 15 procedures (93%), and durable success in 7 of 15(47%). The mean duration of catheter function was 157 (range, 30 to 578) days. After manipulation, abdominal pain developed in eight patients and peritonitis in two, but with conservative treatment, these symptoms improved. The correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance is an effective means of restoring catheter function and may be an effective alternative to surgical reimplantation of the catheter, or hemodialysis.

  14. Effect of two different short peripheral catheter materials on phlebitis development.

    Science.gov (United States)

    Karadağ, A; Görgülü, S

    2000-01-01

    One of the most common causes of phlebitis in hospitalized patients is intravenous catheters. The material of the catheter is a determining factor in the development of phlebitis, as are factors such as age, gender, and medical diagnosis of the patient. The aim of this study, conducted in the coronary care unit of a 384-bed hospital in Ankara, Turkey, was to determine the effect of two different short peripheral catheters on phlebitis development caused by i.v. treatment. Overall, 255 patients constituted the study sample (130 with Teflon, 125 with Vialon catheters). Both groups were followed up for phlebitis development for 6 days. The total phlebitis rate was 36.8%, with almost half of the patients (49.2%) in the Teflon catheter group and 24.0% of patients in the Vialon catheter group. A significant statistical relationship was found between phlebitis rate and variables such as gender, catheter material, and indwelling time. The results of the study demonstrate that Vialon catheters are associated with less risk of catheter-induced phlebitis than are Teflon catheters. PMID:11272972

  15. Interventional radiologic placement of tunneled central venous catheters : results and complications in 557 cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Kyo; Do, Young Soo; Paik, Chul H. [Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)] (and others)

    1999-05-01

    To evaluate prospectively the results of interventional radiologic placement of tunneled central venous catheters, and subsequent complications. Between April 1997 and April 1998, a total of 557 tunneled central venous catheters were percutaneously placed in 517 consecutive patients in an interventional radiology suite. The indications were chemotherapy in 533 cases, total parenteral nutrition in 23 and transfusion in one. Complications were evaluated prospectively by means of a chart review, chest radiography, central vein angiography and blood/catheter culture. The technical success rate for tunneled central venous catheter placement was 100% (557/557 cases). The duration of catheter placement ranged from 4 to 356 (mean, 112{+-}4.6) days; Hickman catheters were removed in 252 cases during follow-up. Early complications included 3 cases of pneumothorax(0.5%), 4 cases of local bleeding/hematoma(0.7%), 2 cases of primary malposition(0.4%), and 1 case of catheter leakage(0.2%). Late complications included 42 cases of catheter-related infection(7.5%), 40 cases of venous thrombosis (7.2%), 18 cases of migration (3.2%), 5 cases of catheter / pericatheter of occlusion(0.8%), and 1 case of pseudoaneurysm(0.2%). The infection rate and thrombosis rate per 1000 days were 1.57 and 1.50, respectively. The technical success rate of interventional radiologic placement of tunneled central venous catheters was high. In comparison to conventional surgical placement, it is a more reliable method and leads to fewer complications.

  16. Study on Acoustic Catheter of Boiler Tube Leakage Monitoring Systems

    Science.gov (United States)

    Lv, Yongxing; Feng, Qiang

    Boiler tube leakage is the major reason of affecting the safe operation of the unit now, there are 3 methods of the "four tube" leakage detection: Traditional method, filtering method and acoustic spectrum analysis, acoustic spectrum analysis is the common method, but this method have low sensitivity and the sensor damage easily. Therewith, designed the special acoustic catheter with acoustic resonance cavity type, proved by experiments, the acoustic catheter with acoustic resonance cavity type can enhance leakage sound, can accurately extract leakage signals, has high sensitivity, and can avoid the effect of sensor by fire and hot-gas when the furnace is in positive pressure situation, reduce the installation and maintenance costs of the boiler tube leakage monitor system.

  17. Irrigated Tip Catheters for Radiofrequency Ablation in Ventricular Tachycardia

    Directory of Open Access Journals (Sweden)

    Andreas Müssigbrodt

    2015-01-01

    Full Text Available Radiofrequency (RF ablation with irrigated tip catheters decreases the likelihood of thrombus and char formation and enables the creation of larger lesions. Due to the potential dramatic consequences, the prevention of thromboembolic events is of particular importance for left-sided procedures. Although acute success rates of ventricular tachycardia (VT ablation are satisfactory, recurrence rate is high. Apart from the progress of the underlying disease, reconduction and the lack of effective transmural lesions play a major role for VT recurrences. This paper reviews principles of lesion formation with radiofrequency and the effect of tip irrigation as well as recent advances in new technology. Potential areas of further development of catheter technology might be the improvement of mapping by better substrate definition and resolution, the introduction of bipolar and multipolar ablation techniques into clinical routine, and the use of alternative sources of energy.

  18. Nursing and safety of silver needle diathermy treating ankylosing spondylitis.

    Science.gov (United States)

    Ning, Huaxiu; Wang, Yun; Yuan, Yiwen; Ning, Huaying

    2015-03-01

    This paper aims to discuss the nursing and safety of silver needle diathermy in the treatment for ankylosing spondylitis. We nursed 46 patients with ankylosing spondylitis treated with silver needle diathermy. Specific nursing was focused on physical condition evaluation and mental nursing before treatment, observation during and after treatment, diet nursing, needle eye nursing, functional training and propaganda and education when discharged. The result suggested that all the patients received mental nursing, diet guide, skin care, health education, functional training and follow-up visit from the nurse and all of them could endure silver needle diathermy as discomfort or drug allergy was barely found, so were slight scald and skin infection nearby the needle eye caused by fainting during acupuncture, accidental puncture or overheat. Follow-up visit showed that no patient suffered obvious untoward effect and the pain, joint range of motion and living condition were distinctly improved a week after discharging. In conclusion, during the treatment for ankylosing spondylitis applying silver needle diathermy, the nursing before, during and after the treatment can obviously reduce the complication, accelerate the recovery, which is highly safe.

  19. Needle stick injury in a radiology department: a decade analysis

    International Nuclear Information System (INIS)

    Objectives: To determine the frequency of needle stick injury in health care workers of radiology department. Study type, settings and duration: Cross sectional, observational study conducted at the Radiology department of Aga Khan University hospital from January 2000 to May 2010. Subject and Methods: All self-reported needle stick injuries data of Health care workers of radiology department was recorded. The personnel involved (Radiologist, resident, radiographer, nurses etc), area of working and the causes of injury were identified including the procedural or post procedural details. Patient's status of hepatitis or blood borne infection was also noted. Data was recorded and analyzed in Excel worksheet. Results: A total of 55 health workers reported needle stick injuries at all sections of radiology departments with maximum number needle stick injuries at general radiography, fluoroscopy and IVP section. Radiographers and radiology residents received the maximum number of injuries. Major cause of injury was cannulation however, many injuries occurred during disposing or handling of bin. In majority of cases the patients were not infected with any known blood borne infections. Conclusions: Doctors and nurses get needle-stick injuries while carrying out clinical procedures, while, ancillary staff get infected post procedure during disposal of garbage. Policy message: Good occupational health and safety practices must be promoted to all staff. Safer disposal of needles is an important area where practice and procedure needs to be carefully reviewed. It is necessary to undertake a risk assessment, to offer counseling and Post Exposure Prophylaxis and treatment where necessary. (author)

  20. Neuromuscular Damage and Repair after Dry Needling in Mice

    Directory of Open Access Journals (Sweden)

    Ares Domingo

    2013-01-01

    Full Text Available Objective. Some dry needling treatments involve repetitive and rapid needle insertions into myofascial trigger points. This type of treatment causes muscle injury and can also damage nerve fibers. The aim of this study is to determine the injury caused by 15 repetitive punctures in the muscle and the intramuscular nerves in healthy mouse muscle and its ulterior regeneration. Methods. We repeatedly needled the levator auris longus muscle of mice, and then the muscles were processed with immunohistochemistry, methylene blue, and electron microscopy techniques. Results. Three hours after the dry needling procedure, the muscle fibers showed some signs of an inflammatory response, which progressed to greater intensity 24 hours after the procedure. Some inflammatory cells could still be seen when the muscle regeneration was almost complete seven days after the treatment. One day after the treatment, some changes in the distribution of receptors could be observed in the denervated postsynaptic component. Reinnervation was complete by the third day after the dry needling procedure. We also saw very fine axonal branches reinnervating all the postsynaptic components and some residual sprouts the same day. Conclusion. Repeated dry needling punctures in muscle do not perturb the different stages of muscle regeneration and reinnervation.

  1. Development of A MEMS Based Manometric Catheter for Diagnosis of Functional Swallowing Disorders

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, H Y [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Hariz, A J [School of Electrical and Information Engineering, University of South Australia (Australia); Omari, T [Centre for Paediatric and Adolescent Gastroenterology, Women' s and Children' s Hospital, Adelaide (Australia); Teng, M F [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Sii, D [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Chan, S [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Lau, L [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Tan, S [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Lin, G [Centre for Advanced Manufacturing Research, University of South Australia, Adelaide (Australia); Haskard, M [School of Electrical and Information Engineering, University of South Australia (Australia); Mulcahy, D; Bakewell, M [Centre for Paediatric and Adolescent Gastroenterology, Women' s and Children' s Hospital, Adelaide (Australia)

    2006-04-01

    Silicon pressure sensors based on micro-electro-mechanical-systems (MEMS) technologies are gaining popularity for applications in bio-medical devices. In this study, a silicon piezo-resistive pressure sensor die is used in a feasibility study of developing a manometric catheter for functional swallowing disorders diagnosis. The function of a manometric catheter is to measure the peak and intrabolus pressures along the esophageal segment during the swallowing action. Previous manometric catheters used the water perfusion technique to measure the pressure changes. This type of catheter is reusable, large in size and the pressure reading is recorded by an external transducer. Current manometric catheters use a solid state pressure sensor on the catheter itself to measure the pressure changes. This type of catheter reduces the discomfort to the patient but it is reusable and is very expensive. We carried out several studies and experiments on the MEMS-based pressure sensor die, and the results show the MEMS-based pressure sensors have a good stability and a good linearity output response, together with the advantage of low excitation biasing voltage and extremely small size. The MEMS-based sensor is the best device to use in the new generation of manometric catheters. The concept of the new MEMS-based manometric catheter consists of a pressure sensing sensor, supporting ring, the catheter tube and a data connector. Laboratory testing shows that the new calibrated catheter is capable of measuring pressure in the range from 0 to 100mmHg and maintaining stable condition on the zero baseline setting when no pressure is applied. In-vivo tests are carried out to compare the new MEMS based catheter with the current version of catheters used in the hospital.

  2. Needle core biopsy for breast lesions: An audit of 467 needle core biopsies

    Directory of Open Access Journals (Sweden)

    Selvi Radhakrishna

    2013-01-01

    Full Text Available Background: Breast cancer is the commonest cancer among women in urban India. Triple assessment includes clinical, radiological and cytological assessment of breast lesions. Guided core needle biopsy has replaced fine needle aspiration cytology in most of the western countries. In resource poor countries FNAC is still a very valuable and cost effective method to diagnose breast lesions. Pitfalls include increased rates of non diagnostic smears, and inadequate smears. Further procedures may be required and this increases the cost, anxiety and delay in diagnosis. Aims: The aim of this study is to analyze the concordance of radiological and histopathology findings in BI-RADS category 3,4,5 lesions following a core biopsy. Materials and Methods: Data was retrospectively collected from consecutive symptomatic and opportunistic screen detected patients with abnormalities who underwent ultrasound guided interventional procedures from Jan 2010 to Aug 2011. Symptomatic patients underwent clinical examination, mammogram and breast ultrasound. Women under 35 years of age had only breast ultrasound. Core biopsy was performed under ultrasound guidance or clinically by a breast surgeon/ radiologist for BI-RADS category 3,4,5 lesions. Statistical Methods: Chi square test was done to show the strength of association of imaging findings and histopathology results of core biopsy. Results: 437 patients were symptomatic and 30 patients had screen detected abnormalities. The positive predictive value for BI-RADS 5 lesions for malignancy is 93.25% and the negative predictive value of BI-RADS category 3 lesions for cancer is 98.4%. False negative diagnosis on core biopsy was 0.85%. We were able to defer surgery in 60% of the patients with a clear radiological and pathological benign diagnosis. Conclusion: The PPV and NPV for cancer is high with needle core biopsy in BI-RADS 3,4,5 lesions. Where there is no discordance between clinical, radiology and pathology findings

  3. Micro-needle electro-tactile display.

    Science.gov (United States)

    Tezuka, Mayuko; Kitamura, Norihide; Miki, Norihisa

    2015-08-01

    Haptic feedback is strongly demanded for high-precision robot-assisted surgery and teleoperation. The haptic feedback consists of force and tactile feedback, however tactile feedback has been little studied and the size and weight of the system poses challenges for practical applications. In this paper we propose a sheet-type wearable electro-tactile display which provides tactile sensations to the user as the feedback at a low voltage and power consumption. The display possesses needle-shaped electrodes, which can penetrate through the high-impedance stratum corneum. We developed the fabrication process and, as the first step, we investigated the tactile sensation that can be created to the fingertip by the display. Rough and smooth surfaces were successfully presented to the user. Then, we characterized the tactile display when used on the forearm, in particular, with respect to the spatial resolution. These tactile displays can be used to inform the user of the surface property of the parts of interest, such as tumor tissues, and to guide him in the manipulation of surgery robots. PMID:26737606

  4. Fine needle aspiration cytology in leprosy

    Directory of Open Access Journals (Sweden)

    Prasad PVS

    2008-01-01

    Full Text Available Background: Laboratory diagnosis of leprosy by slit skin smear and skin biopsy is simple but both techniques have their own limitations. Slit skin smear is negative in paucibacillary cases whereas skin biopsy is an invasive technique. Fine needle aspiration cytology (FNAC from skin lesions in leprosy with subsequent staining with May-Grunwald-Giemsa (MGG stain has been found useful. Aim: To evaluate the possible role of cytology in classifying leprosy patients. Methods: Seventy-five untreated cases of leprosy attending the outpatient department were evaluated. Smears were taken from their skin lesions and stained using the MGG technique. Skin biopsy was also done from the lesions, which was compared with cytology smears. Results: A correlation of clinical features with FNAC was noticed in 87.5% of TT, 92.1% of BT, 81% of BL, and 66% of LL cases. Correlation of clinical with histopathological diagnoses revealed 12.5% specificity in TT leprosy, 55.3% in BT, 52.4% in BL and 50% in LL, and 100% in neuritic and histoid leprosy cases. Both correlations were found to be statistically significant by paired t test analysis. Thus, it was possible to distinguish the tuberculoid types by the presence of epithelioid cells and the lepromatous types by the presence of lymphocytes and foamy macrophages. Conclusion: FNAC may be used to categorize the patients into paucibacillary and multibacillary types, but is not a very sensitive tool to classify the patients across the Ridley-Jopling spectrum.

  5. Analysis on enzymatic browning in pine needles

    Energy Technology Data Exchange (ETDEWEB)

    Kong, K.H.; Park, H.J.; Choi, S.S.; Cho, S.H. [Chung-Ang University, Seoul (Korea); Kim, Y.T. [Aoyama Gakuin University, Tokyo (Japan)

    1999-06-01

    Tyrosinases are related to the enzymatic browning of plants and attract the major scientific interest for the prevention of it. Three tyrosinase isozymes (P{sub 1}, P{sub 2} and P{sub 3}) from pine needles were purified to homogeneity and characterized the factors that affect their activities. The L-ascorbic acid and {beta}-mercaptoethanol notably inhibited the enzymatic activities of the three isozymes. The sodium diethyldithiocarbamate was a competitive inhibitor of isozymes with the K{sub i} values of P{sub 1}(0.30 mM), P{sub 2}(0.015 mM) and P{sub 3}(0.019 mM), respectively. Their enzyme activities were however, increased by the addition of most metal ions. The optimum pH for the three isozymes was 9.0{approx}9.5 and the optimum temperatures ranged from 55 to 60{sup o} C using L-DOPA as substrate. 15 refs., 3 figs., 2 tabs.

  6. Susuks (charm needles) in the craniofacial region

    International Nuclear Information System (INIS)

    We conducted a study to determine the numbers of susuks (charm needles) and their distribution in the craniofacial region of susuk wearers, and the sex, racial affiliation, and age of the wearers. In addition, we sought to determine whether the presence of susuks posed any potential hazard to patients undergoing magnetic resonance imaging (MRI). We studied various radiographs of 33 susuk wearers (age range, 33-69 years) and investigated the most common sites of insertion in the craniofacial region. A susuk was also suspended inside a 1.5-T MRI machine to determined whether it was attracted by the machine's magnet. The largest number of susuks that we observed in the craniofacial region was 39 pins, and susuks were particularly numerous in Malay Muslim women. Other sites with susuks were the maxillofacial region (except the temporomandibular region) and the forehead. The susuks showed no ferromagnetic characteristics. As susuks are made from gold, they are generally biocompatible with human tissue and do not cause problems to their wearers. Gold and the other minor metal constituents found in susuks have no ferromagnetic characteristics and therefore pose no hazard to patients undergoing MRI. (author)

  7. Polyazole hollow fiber membranes for direct contact membrane distillation

    KAUST Repository

    Maab, Husnul

    2013-08-07

    Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

  8. Hollow porous-wall glass microspheres for hydrogen storage

    Science.gov (United States)

    Heung, Leung K.; Schumacher, Ray F.; Wicks, George G.

    2010-02-23

    A porous wall hollow glass microsphere is provided having a diameter range of between 1 to 200 microns, a density of between 1.0 to 2.0 gm/cc, a porous-wall structure having wall openings defining an average pore size of between 10 to 1000 angstroms, and which contains therein a hydrogen storage material. The porous-wall structure facilitates the introduction of a hydrogen storage material into the interior of the porous wall hollow glass microsphere. In this manner, the resulting hollow glass microsphere can provide a membrane for the selective transport of hydrogen through the porous walls of the microsphere, the small pore size preventing gaseous or liquid contaminants from entering the interior of the hollow glass microsphere.

  9. Preparation of Polyvinylidene Fluoride (PVDF Hollow Fiber Hemodialysis Membranes

    Directory of Open Access Journals (Sweden)

    Qinglei Zhang

    2014-02-01

    Full Text Available In this study, the polyvinylidene fluoride (PVDF hollow fiber hemodialysis membranes were prepared by non-solvent induced phase separation (NIPS. The influences of PVDF membrane thickness and polyethylene glycol (PEG content on membrane morphologies, pore size, mechanical and permeable performance were investigated. It was found that membrane thickness and PEG content affected both the structure and performance of hollow fiber membranes. The tensile strength and rejection of bovine serum albumin (BSA increased with increasing membrane thickness, while the Ultrafiltration flux (UF flux of pure water was the opposite. The tensile strength, porosity and rejection of BSA increased with increasing PEG content within a certain range. Compared with commercial F60S membrane, the PVDF hollow fiber membrane showed higher mechanical and permeable performance. It was proven that PVDF material had better hydrophilicity and lower BSA adsorption, which was more suitable for hemodialysis. All the results indicate that PVDF hollow fiber membrane is promising as a hemodialysis membrane.

  10. Preparation of Polyvinylidene Fluoride (PVDF) Hollow Fiber Hemodialysis Membranes.

    Science.gov (United States)

    Zhang, Qinglei; Lu, Xiaolong; Zhao, Lihua

    2014-01-01

    In this study, the polyvinylidene fluoride (PVDF) hollow fiber hemodialysis membranes were prepared by non-solvent induced phase separation (NIPS). The influences of PVDF membrane thickness and polyethylene glycol (PEG) content on membrane morphologies, pore size, mechanical and permeable performance were investigated. It was found that membrane thickness and PEG content affected both the structure and performance of hollow fiber membranes. The tensile strength and rejection of bovine serum albumin (BSA) increased with increasing membrane thickness, while the Ultrafiltration flux (UF) flux of pure water was the opposite. The tensile strength, porosity and rejection of BSA increased with increasing PEG content within a certain range. Compared with commercial F60S membrane, the PVDF hollow fiber membrane showed higher mechanical and permeable performance. It was proven that PVDF material had better hydrophilicity and lower BSA adsorption, which was more suitable for hemodialysis. All the results indicate that PVDF hollow fiber membrane is promising as a hemodialysis membrane. PMID:24957122

  11. PYRAMIDAL-HOLLOW-BEAM DIPOLE TRAP FOR ALKALI ATOMS

    Institute of Scientific and Technical Information of China (English)

    YIN JIAN-PING; GAO WEI-JIAN; WANG YU-ZHU; ZHU YI-FU; WANG YI-QIU

    2000-01-01

    We propose a dark gravito-optical dipole trap, for alkali atoms, consisting of a blue-detuned, pyramidal-hollow laser beam propagating upward and the gravity field. When cold atoms from a magneto-optical trap are loaded into the pyramidal-hollow beam and bounce inside the pyramidal-hollow beam, they experience efficient Sisyphus cooling and geometric cooling induced by the pyramidal-hollow beam and the weak repumping beam propagating downward. Our study shows that an ultracold and dense atomic sample with an equilibrium 3D momentum of ~ 3hk and an atomic density above the point of Bose-Einstein condensation may be obtained in this pure optical trap.

  12. Biomimetic synthesis of calcium-strontium apatite hollow nanospheres

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this work,calcium-strontium apatite (Sr-HA) hollow nanospheres were synthesized by a facile biomimetic method.The structure and property of Sr-HA were characterized by FESEM,TEM,HRTEM,XRD and FT-IR spectroscopy.The influences of different ratios of calcium and strontium on the morphologies of the Sr-HA products were investigated.The experimental results revealed that the hollow spherical Sr-HA,with a size of 30-120 nm in diameter,could be synthesized when the molar ratio of Ca/Sr was 1:1.The possible formation mechanism of the hollow Sr-HA was proposed.The drug release experiments indicated that the hollow spherical Sr-HA had the property of sustained release.

  13. Synthesis, characterization and properties of hollow nickel phosphide nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Ni Yonghong; Tao Ali; Hu Guangzhi; Cao Xiaofeng; Wei Xianwen; Yang Zhousheng [College of Chemistry and Materials Science, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, Wuhu 241000 (China)

    2006-10-14

    Nickel phosphide (Ni{sub 12}P{sub 5}) hollow nanospheres with a mean diameter of 100 nm and a shell thickness of 15-20 nm have been successfully prepared by a hydrothermal-microemulsion route, using NaH{sub 2}PO{sub 2} as a phosphorus source. XRD, EDS (HR)TEM, SEM and the SAED pattern were used to characterize the final product. Experiments showed that the as-prepared nickel phosphide hollow nanospheres could selectively catalytically degrade some organic dyes such as methyl red and Safranine T under 254 nm UV light irradiation. At the same time, the nickel phosphide hollow nanospheres showed a stronger ability to promote electron transfer between the glass-carbon electrode and adrenalin than nickel phosphide honeycomb-like particles prepared by a simple hydrothermal route. A possible formation process for nickel phosphide hollow nanospheres was suggested based on the experimental results.

  14. Hollow Rotor Progressing Cavity Pump Technique for Oil Production

    Institute of Scientific and Technical Information of China (English)

    Cao Gang

    2002-01-01

    @@ Features of Hollow RotorProgressing Cavity Pump(HRPCP) (1) Keep the path forPCP well-flushing.Clean over the producing wells quickly without shutting off the wells. Heat loss is low while the efficiency is high.

  15. Neuropsychological Decline After Catheter Ablation of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Schwarz, N

    2011-09-01

    Full Text Available The article “Neuropsychological decline after cath- eter ablation of atrial fibrillation” by Schwarz et al. is the first publication that focused on cognitive side effects of elective circumferential pulmonary vein isolation (PVI.1 Adverse neuropsychological changes after left atrial catheter ablation, as report- ed in this paper, were found in verbal memory and the result, conjoined with ischemic brain lesions, might represent cerebral side-effects of the ablation procedure.

  16. EVALUATION OF A NEW CATHETER FOR ESOPHAGEAL PH MONITORING

    NARCIS (Netherlands)

    KUIT, JA; SCHEPEL, SJ; BIJLEVELD, CMA; KLEIBEUKER, JH

    1991-01-01

    A new catheter, provided with an Ion Sensitive Field Effect Transistor as a pH sensor and incorporating a reference electrode, was evaluated for esophageal pH recording. The pH-sensitivity was 54 mV/pH in vitro, with a linear response between pH 2 and pH 9. Clinical semi-ambulatory 24-hour esophagea

  17. A catheter related sepsis case caused by Pantoea agglomerans

    Directory of Open Access Journals (Sweden)

    Fadime Yılmaz

    2015-04-01

    microorganism was sensitive to piperacillin-tazobactam, so, patient's therapy was not changed. After treatment, when the general condition of the patient healed, he was discharged by ending antibiotics on the sixteenth day. This case report, is intended to call attention to the risk of the growth of catheter-associated sepsis and antibioterapi are lated to P. agglomerans which is rarely seen on immunocompromised patients.

  18. Determination of lesion size by ultrasound during radiofrequency catheter ablation.

    Science.gov (United States)

    Awad, S; Eick, O

    2003-01-01

    The catheter tip temperature that is used to control the radiofrequency generator output poorly correlates to lesion size. We, therefore, evaluated lesions created in vitro using a B-mode ultrasound imaging device as a potential means to assess lesion generation during RF applications non-invasively. Porcine ventricular tissue was immersed in saline solution at 37 degrees C. The catheter was fixed in a holder and positioned in a parallel orientation to the tissue with an array transducer (7.5 MHz) app. 3 cm above the tissue. Lesions were produced either in a temperature controlled mode with a 4-mm tip catheter with different target temperatures (50, 60, 70 and 80 degrees C, 80 W maximum output) or in a power controlled mode (25, 50 and 75 W, 20 ml/min irrigation flow) using an irrigated tip catheter. Different contact forces (0.5 N, 1.0 N) were tested, and RF was delivered for 60 s. A total of 138 lesions was produced. Out of these, 128 could be identified on the ultrasound image. The lesion depth and volume was on average 4.1 +/- 1.6 mm and 52 +/- 53 mm3 as determined by ultrasound and 3.9 +/- 1.7 mm and 52 +/- 55 mm3 as measured thereafter, respectively. A linear correlation between the lesion size determined by ultrasound and that measured thereafter was demonstrated with a correlation coefficient of r = 0.87 for lesion depth and r = 0.93 for lesion volume. We conclude that lesions can be assessed by B-mode ultrasound imaging. PMID:12910859

  19. Catheter-related blood stream infection caused by Raoultella ornithinolytica.

    Science.gov (United States)

    Sękowska, Alicja; Dylewska, Katarzyna; Gospodarek, Eugenia; Bogiel, Tomasz

    2015-11-01

    Raoultella spp. representatives are Gram-negative capsulated, nonmotile rods. These bacteria are found in the natural environment: plants, water, soil and insects. R. ornithinolytica is one of the three species of Raoultella. R. ornithinolytica is the only species within the genus which has the ability to produce ornithine decarboxylase. Human infections related to R. ornithinolytica are exceedingly rare. The present case report describes catheter-related blood stream infection caused by R. ornithinolytica and successfully treated with antibiotic therapy.

  20. Remote control catheter navigation: options for guidance under MRI

    OpenAIRE

    Muller Leah; Saeed Maythem; Wilson Mark W; Hetts Steven W

    2012-01-01

    Abstract Background Image-guided endovascular interventions have gained increasing popularity in clinical practice, and magnetic resonance imaging (MRI) is emerging as an attractive alternative to X-ray fluoroscopy for guiding such interventions. Steering catheters by remote control under MRI guidance offers unique challenges and opportunities. Methods In this review, the benefits and limitations of MRI-guided remote control intervention are addressed, and the tools for guiding such intervent...

  1. Microbiological pattern of arterial catheters in the intensive care unit

    Directory of Open Access Journals (Sweden)

    Patel Bharat

    2010-10-01

    Full Text Available Abstract Background Intravascular catheter related infection (CRI is one of the most serious nosocomial infections. Diagnostic criteria include a positive culture from the catheter tip along with blood, yet in many patients with signs of infection, current culture techniques fail to identify pathogens on catheter segments. We hypothesised that a molecular examination of the bacterial community on short term arterial catheters (ACs would improve our understanding of the variety of organisms that are present in this niche environment and would help develop new methods for the diagnosis of CRI. Results The whole bacterial community presenting on all ACs was evaluated by molecular methods, i.e., a strategy of whole community DNA extraction, PCR amplification followed by cloning and 16S rDNA sequence analysis. Ten ACs were removed from patients suspected of CRI and 430 clones from 5 "colonised" and 5 "uncolonised" (semi-quantitative method AC libraries were selected for sequencing and subsequent analysis. A total of 79 operational taxonomic units (OTUs were identified at the level of 97% similarity belonging to six bacterial divisions. An average of 20 OTUs were present in each AC, irrespective of colonisation status. Conventional culture failed to reveal the majority of these bacteria. Conclusions There was no significant difference in the bacterial diversity between the 'uncolonised' and 'colonised' ACs. This suggests that vascular devices cultured conventionally and reported as non infective may at times potentially be a significant source of sepsis in critically ill patients. Alternative methods may be required for the accurate diagnosis of CRI in critically ill patients.

  2. Potential In Vivo UVC Disinfection of Catheter Lumens: Estimation of the Doses Received by the Blood Flow Outside the Catheter Tip Hole

    DEFF Research Database (Denmark)

    Bak, Jimmy; Jørgensen, Thomas Martini; Helfmann, Jurgen;

    2011-01-01

    We have demonstrated that it is possible to launch UVC LED light into bacterial contaminated polymer tubes/catheters and disinfect the intraluminal space of these tubes. This can be achieved by UVC treatment of the catheters on a regular basis. Catheters are in the distal end equipped with an exi...... reason why the UVC exposure to the blood in the catheter application is so low. The very low dose received by the blood through the catheter tip indicated that possible side effects are negligible and makes the UV disinfection technique feasible in a clinical setting....... by calculations that very small effective doses are exposed to the blood (ca 10(-4) J m(-2) ). This dosage level is very low compared with UVC doses reported from other therapeutic applications. The very short residence time of the blood constituents in the irradiated volume in front of the exit hole is the main...

  3. Catheter ablation of atrial fibrillation in the elderly

    Science.gov (United States)

    Lioni, Louiza; Letsas, Konstantinos P.; Efremidis, Michael; Vlachos, Konstantinos; Giannopoulos, Georgios; Kareliotis, Vasileios; Deftereos, Spyridon; Sideris, Antonios

    2014-01-01

    Background Atrial fibrillation (AF) catheter ablation has emerged as a promising treatment strategy for AF, but has not been widely adopted in the elderly population. The present study aimed to determine the safety and efficacy of AF catheter ablation in the elderly population. Methods and Results The study population consisted of 316 patients with paroxysmal AF who underwent left atrial ablation. Ninety-five patients were ≥ 65 years (48 males, mean age 68.9 ± 3.0 years old) and 221 patients were < 65 years old (130 males, mean age 52.5 ± 10.4 years old). After a mean follow-up period of 34.0 ± 15.1 months, 55 (57.9%) patients in the elderly group were free from arrhythmia recurrence compared with 149 (67.4%) patients in the younger group (P = 0.169). Procedural complications were uncommon in both study groups. In logistic regression analysis, left atrial diameter (P = 0.003), hypertension (P = 0.001), dyslipidemia (P = 0.039), and coronary artery disease (P = 0.018) were independent predictors of AF recurrence in the elderly population. Conclusions Catheter ablation of AF is safe and effective in older patients. Invasive strategies should be considered as an alternative choice in symptomatic elderly patients with AF. PMID:25593577

  4. Catheter ablation of atrial fibrillation in the elderly

    Institute of Scientific and Technical Information of China (English)

    Louiza Lioni; Konstantinos P Letsas; Michael Efremidis; Konstantinos Vlachos; Georgios Giannopoulos; Vasileios Kareliotis; Spyridon Deftereos; Antonios Sideris

    2014-01-01

    Background Atrial fibrillation (AF) catheter ablation has emerged as a promising treatment strategy for AF, but has not been widely adopted in the elderly population. The present study aimed to determine the safety and efficacy of AF catheter ablation in the elderly popula-tion. Methods and Results The study population consisted of 316 patients with paroxysmal AF who underwent left atrial ablation. Ninety-five patients were≥65 years (48 males, mean age 68.9 ± 3.0 years old) and 221 patients were<65 years old (130 males, mean age 52.5 ± 10.4 years old). After a mean follow-up period of 34.0 ± 15.1 months, 55 (57.9%) patients in the elderly group were free from ar-rhythmia recurrence compared with 149 (67.4%) patients in the younger group (P=0.169). Procedural complications were uncommon in both study groups. In logistic regression analysis, left atrial diameter (P=0.003), hypertension (P=0.001), dyslipidemia (P=0.039), and coronary artery disease (P=0.018) were independent predictors of AF recurrence in the elderly population. Conclusions Catheter ablation of AF is safe and effective in older patients. Invasive strategies should be considered as an alternative choice in symptomatic elderly patients with AF.

  5. Optoacoustic sensing for target detection inside cylindrical catheters

    Science.gov (United States)

    Tavakoli, Behnoosh; Guo, Xiaoyu; Taylor, Russell H.; Kang, Jin U.; Boctor, Emad M.

    2014-03-01

    Optoacoustic sensing is a hybrid technique that combines the advantages of high sensing depth of ultrasound with contrast of optical absorption. In this study a miniature optoacoustic probe that can characterize the target properties located at the distal end of a catheter is investigated. The probe includes an optical fiber to illuminate the target with the pulsed laser light and a hydrophone to detect the generated optoacoustic signal. The probe is designed for the forwardsensing and therefore the acoustic signal propagates along the tube before being detected. Due to the circular geometry, the waves inside the tube are highly complex. A three dimensional numerical simulation is performed to model the optoacoustic wave generation and propagation inside the water filled cylindrical tubes. The effect of the boundary condition, tube diameter and target size on the detected signal is systematically evaluated. A prototype of the probe is made and tested for detecting an absorbing target inside a 2mm diameter tube submerged in water. The preliminary experimental results corresponding to the simulation is acquired. Although many different medical applications for this miniature probe may exist, our main focus is on detecting the occlusion inside the ventricular shunts. These catheters are used to divert the excess cerebrospinal fluid to the absorption site and regulate inter cranial pressure of hydrocephalous patients. Unfortunately the malfunction rate of these catheters due to blockage is very high. This sensing tool could locate the occluding tissue non-invasively and can potentially characterize the occlusion composites by scanning at different wavelengths of the light.

  6. Catheter-associated urinary tract infection: antimicrobial sensitivity profile

    Directory of Open Access Journals (Sweden)

    Silvana Kelie Souza de Almeida Barros

    2013-11-01

    Full Text Available This descriptive quantitative study aimed to analyze the prevalence of microorganisms and the antimicrobial sensitivity profile from urine cultures of patients with catheter-associated urinary tract infection. We reviewed 394 medical records of adults hospitalized in the Intensive Care Units of the University Hospital of Londrina, Paraná, Brazil, from April to December 2011. The prevalence of catheter-associated urinary tract infection was of 34.0% (134 and 2.2% (3 of these patients developed sepsis. The most common microorganisms found in the urine cultures were Candida sp (44.4%, Acinetobacter baumannii (9.7% and Pseudomonas aeruginosa (9.2%. This last one showed resistance of 86.7% to third-generation cephalosporins and the Acinetobacter baumannii showed resistance of 83.3% to carbapenems. Klebsiella pneumonia had 87.5% of resistance to third and fourth generation cephalosporins and 75.0% to carbapenems. We concluded that bacterial resistance is frequent in catheter-associated urinary tract infection and that we should emphasize the control measures.

  7. Ventriculoperitoneal shunt malfunction caused by proximal catheter fat obstruction.

    Science.gov (United States)

    Mizrahi, Cezar José; Spektor, Sergey; Margolin, Emil; Shoshan, Yigal; Ben-David, Eliel; Cohen, José E; Moscovici, Samuel

    2016-08-01

    Ventriculoperitoneal (VP) shunt placement is the mainstay of treatment for hydrocephalus, yet shunts remain vulnerable to a variety of complications. Although fat droplet migration into the subarachnoid space and cerebrospinal fluid pathways following craniotomy has been observed, a VP shunt obstruction with fat droplets has never been reported to our knowledge. We present the first reported case of VP shunt catheter obstruction by migratory fat droplets in a 55-year-old woman who underwent suboccipital craniotomy for removal of a metastatic tumor of the left medullocerebellar region, without fat harvesting. A VP shunt was inserted 1month later due to communicating hydrocephalus. The patient presented with gait disturbance, intermittent confusion, and pseudomeningocele 21days after shunt insertion. MRI revealed retrograde fat deposition in the ventricular system and VP shunt catheter, apparently following migration of fat droplets from the fatty soft tissue of the craniotomy site. Spinal tap revealed signs of aseptic meningitis. Steroid treatment for aseptic "lipoid" meningitis provided symptom relief. MRI 2months later revealed partial fat resorption and resolution of the pseudomeningocele. VP shunt malfunction caused by fat obstruction of the ventricular catheter should be acknowledged as a possible complication in VP shunts after craniotomy, even in the absence of fat harvesting.

  8. A Dynamical Training and Design Simulator for Active Catheters

    Directory of Open Access Journals (Sweden)

    Georges Dumont

    2008-11-01

    Full Text Available This work addresses the design of an active multi-link micro-catheter actuated by Shape Memory Alloy (SMA micro actuators. This may be a response to one medical major demand on such devices, which will be useful for surgical explorations and interventions. In this paper, we focus on a training and design simulator dedicated to such catheters. This simulator is based on an original simulation platform (OpenMASK. The catheter is a robotic system, which is evaluated by a dynamical simulation addressing a navigation task in its environment. The design of the prototype and its mechanical model are presented. We develop an interaction model for contact. This model uses a real medical database for which distance cartography is proposed. Then we focus on an autonomous control model based on a multi-agent approach and including the behaviour description of the SMA actuators. Results of mechanical simulations including interaction with the ducts are presented. Furthermore, the interest of such a simulator is presented by applying virtual prototyping techniques for the design optimization. This optimization process is achieved by using genetic algorithms at different stages with respect to the specified task.

  9. Life-threatening vascular complications after central venous catheter placement

    Energy Technology Data Exchange (ETDEWEB)

    Wicky, S.; Meuwly, J.-Y.; Doenz, F.; Uske, A.; Schnyder, P.; Denys, A. [Department of Radiology, University Hospital, Lausanne (Switzerland)

    2002-04-01

    The purpose of this retrospective study was to report 11 cases of severe vascular complications after central venous catheter misplacement. For each patient, data collection included body mass index, the diagnosis at admission, the site of the procedure, the type of catheter, coagulation parameters, the imaging modalities performed and the applied treatment. Eight patients had a lesion of the subclavian artery. Brachiocephalic vein perforations were assessed in three more patients. All patients had a chest roentgenogram after the procedure, six a CT examination, and four an angiographic procedure. Seven patients had a body mass index above 30, and 5 patients had coagulation disorders prior to the procedure. Seven patients were conservatively managed, 2 patients died despite resuscitation, 1 patient was treated with a stent graft, and one by superselective embolization. Subclavian or jugular vein temporary catheter positioning is a practical approach. Identification of any iatrogenic perforation of the subclavian artery or central veins urges obtainment a chest roentgenogram and, when required, a chest CT, selective angiograms or venograms. Body mass index superior to 30, previous unsuccessful catheterization attempts, and coagulation factor depletion seemed to account for risk factors. Recognition of clinical and radiological complications is mandatory. (orig.)

  10. The Malposition of Central Venous Catheters in Children

    International Nuclear Information System (INIS)

    Contemporary medical care, especially in the field of pediatrics often requires central venous line (CVC – Central Venous Catheter) implantation for carrying out treatment. Some conditions are treated intravenously for several months, other require long-term venous access due to periodical administration of medications or daily nutritional supplementation. A total number of 309 CVCs were implanted at Children’s University Hospital in Cracow between January 2011 and December 2012 (24 months). Malposition of the CVC is not common. The target of our article was to present two rare cases of malposition of catheters and two displacements of catheter due to chest tumors, and to enhance the importance of differential diagnostic imaging when difficulties occur. CVC malposition was detected with different imaging modalities followed by appropriate medical procedures. In case of any difficulties with central lines, it is necessary to investigate the underlying cause. The central line team at hospital cooperating with other specialists is needed to detect complications and to prevent them

  11. [Quantitative cultures from catheters, using the Brun Buisson technique].

    Science.gov (United States)

    Soloaga, R; Guelfand, L; Manganello, S; Llanos, A; Cecchi, S; Schmoll, V; Cambareri, M; Fernández, A; Gutfraind, Z; Tokumoto, M

    2002-01-01

    The objective of this collaborative work carried out in the Fundación Favaloro and the Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia, was to determine optimal conditions for incubation (time and atmosphere) of quantitative cultures of catheters processed according to the technique of vortex agitation (Brun Buisson method). From 689 processed catheters, 551 yielded negative cultures. From the 138 positive cultures, 125 yielded monomicrobial cultures and 13 polimicrobial cultures (total number of microorganisms was 151). In the last situation each micoorganism was considered on an individual basis. A total of 58 episodes of catheter related bacteremias occurred, being 52 monomicrobial and 6 polimicrobial (total number of microorganisms was 64). When colony counts were compared in aerobic and in 5-10% CO2 atmospheres, a very good correlation was obtained (p = 0.27; r2 = 0.9268). No advantage was observed by incubating plates for more than 48 hours. Colony counts performed at the second versus the third day, and at the second day versus the seventh, gave very good correlation (p = 0.10 and r2 = 0.9996; p = 0.31 and r2 = 0.9995, respectively).

  12. Flat Bunches with a Hollow Distribution for Space Charge Mitigation

    CERN Document Server

    Oeftiger, Adrian; Findlay, Alan James; Hancock, Steven; Rumolo, Giovanni

    2016-01-01

    Longitudinally hollow bunches provide one means to mitigate the impact of transverse space charge. The hollow distributions are created via dipolar parametric excitation during acceleration in CERN's Proton Synchrotron Booster. We present simulation work and beam measurements. Particular emphasis is given to the alleviation of space charge effects on the long injection plateau of the downstream Proton Synchrotron machine, which is the main goal of this study.

  13. 3D hollow nanostructures as building blocks for multifunctional plasmonics

    KAUST Repository

    De Angelis, Francesco De

    2013-08-14

    We present an advanced and robust technology to realize 3D hollow plasmonic nanostructures which are tunable in size, shape, and layout. The presented architectures offer new and unconventional properties such as the realization of 3D plasmonic hollow nanocavities with high electric field confinement and enhancement, finely structured extinction profiles, and broad band optical absorption. The 3D nature of the devices can overcome intrinsic difficulties related to conventional architectures in a wide range of multidisciplinary applications. © 2013 American Chemical Society.

  14. Preparation of Polyvinylidene Fluoride (PVDF) Hollow Fiber Hemodialysis Membranes

    OpenAIRE

    Qinglei Zhang; Xiaolong Lu; Lihua Zhao

    2014-01-01

    In this study, the polyvinylidene fluoride (PVDF) hollow fiber hemodialysis membranes were prepared by non-solvent induced phase separation (NIPS). The influences of PVDF membrane thickness and polyethylene glycol (PEG) content on membrane morphologies, pore size, mechanical and permeable performance were investigated. It was found that membrane thickness and PEG content affected both the structure and performance of hollow fiber membranes. The tensile strength and rejection of bovine serum a...

  15. Scanning optical pyrometer for measuring temperatures in hollow cathodes

    OpenAIRE

    Polk, J. E.; Marrese-Reading, C. M.; Thornber, B.; Dang, L.; Johnson, L. K.; Katz, I

    2007-01-01

    Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measu...

  16. Highly efficient fluorescence sensing with hollow core photonic crystal fibers

    DEFF Research Database (Denmark)

    Smolka, Stephan; Barth, Michael; Benson, Oliver

    2008-01-01

    We investigate hollow core photonic crystal fibers for ultra-sensitive fluorescence detection by selectively infiltrating the central hole with fluorophores. Dye concentrations down to 10(-9) M can be detected using only nanoliter sample volumes.......We investigate hollow core photonic crystal fibers for ultra-sensitive fluorescence detection by selectively infiltrating the central hole with fluorophores. Dye concentrations down to 10(-9) M can be detected using only nanoliter sample volumes....

  17. Laser-plasma-based linear collider using hollow plasma channels

    Science.gov (United States)

    Schroeder, C. B.; Benedetti, C.; Esarey, E.; Leemans, W. P.

    2016-09-01

    A linear electron-positron collider based on laser-plasma accelerators using hollow plasma channels is considered. Laser propagation and energy depletion in the hollow channel is discussed, as well as the overall efficiency of the laser-plasma accelerator. Example parameters are presented for a 1-TeV and 3-TeV center-of-mass collider based on laser-plasma accelerators.

  18. Facile synthesis of ZnO hollow fibres

    Indian Academy of Sciences (India)

    B T Su; K Wang; X W Zuo; H M Mu; N Dong; Y C Tong; J Bai; Z Q Lei

    2007-12-01

    In this paper, cotton fibres were used as bio-template to successfully synthesize new ceramic materials, ZnO hollow fibres and in an effort to explore the synthesis condition, and simplify the synthesis procedure. In this synthesis, a direct thermal decomposition of zinc acetate dihydrate coated on the surface of cotton fibres was explored. The wall porosity of the ZnO hollow fibres was controlled by changing the concentration of zinc acetate aqueous solution.

  19. Percutaneous transthoracic cutting needle biopsy of pulmonary lesions: comparison of the use of 18 and 20 gauge needles

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Chang; Jin, Gong Yong; Han, Young Min; Park, Hak Hun; Kwon, Keun Sang [Chonbuk National University Hospital, Medical School, Research Institute of Clinical Medicine, Jeonju(Korea, Republic of)

    2008-05-15

    We evaluated the usefulness of a CT guided percutaneous transthoracic cutting needle biopsy (PCNB) using a 20 gauge (G) needle for pulmonary lesions after a comparison with the use of an 18 G needle for diagnostic accuracy and complications. From August 2005 to July 2007, 433 patients underwent a CT guided PCNB. A total of 191 patients were excluded from the study as these patients had benign lesions seen after PCNB, but did not receive a confirmation biopsy or undergo follow-up (> 1 year). We evaluated the diagnostic accuracy for the use of PCNB using the Chi-squared test and analyzed which factors (location and size of lesions, diameter of the needle, distance between the pleura and lesions, presence or not of emphysema) were related to occurrence of a pneumothorax after PCNB using a multi-variant regression test. The diagnostic accuracy for malignant lesions with the use of an 18 G and a 20 G needle were 95.4% and 97%, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the use of an 18 G needle were 95.7%, 100%, 100%, and 91.6%. The sensitivity, specificity, PPV, and NPV were 97.8%, 100%, 100%, and 95.0% for the use of a 20 G needle. A pneumothorax occurred in 5.5% (24/433) of the cases and was closely related to the distance from the pleura to the lesions. CT guided PCNB with the use of a 20 gauge needle provided good diagnostic accuracy and the procedure is safe to perform.

  20. Comparison of Fine Needle Aspiration and Fine Needle Nonaspiration Cytology of Thyroid Nodules: A Meta-Analysis

    OpenAIRE

    Hongming Song; Chuankui Wei; Dengfeng Li; Kaiyao Hua; Jialu Song; Niraj Maskey; Lin Fang

    2015-01-01

    Background. Fine needle aspiration cytology (FNAC) and fine needle nonaspiration cytology (FNNAC) are useful cost-effective techniques for preoperatively assessing thyroid lesions. Both techniques have advantages and disadvantages, and there is controversy over which method is superior. This meta-analysis was performed to evaluate the differences between FNAC and FNNAC for diagnosis of thyroid nodules. Methods. Primary publications were independently collected by two reviewers from PubMed, We...