AC electrical breakdown phenomena of epoxy/layered silicate nanocomposite in needle-plate electrodes.

Science.gov (United States)

Park, Jae-Jun; Lee, Jae-Young

2013-05-01

Epoxy/layered silicate nanocomposite for the insulation of heavy electric equipments were prepared by dispersing 1 wt% of a layered silicate into an epoxy matrix with a homogenizing mixer and then AC electrical treeing and breakdown tests were carried out. Wide-angle X-ray diffraction (WAXD) analysis and transmission electron microscopy (TEM) observation showed that nano-sized monolayers were exfoliated from a multilayered silicate in the epoxy matrix. When the nano-sized silicate layers were incorporated into the epoxy matrix, the breakdown rate in needle-plate electrode geometry was 10.6 times lowered than that of the neat epoxy resin under the applied electrical field of 520.9 kV/mm at 30 degrees C, and electrical tree propagated with much more branches in the epoxy/layered silicate nanocomposite. These results showed that well-dispersed nano-sized silicate layers retarded the electrical tree growth rate. The effects of applied voltage and ambient temperature on the tree initiation, growth, and breakdown rate were also studied, and it was found that the breakdown rate was largely increased, as the applied voltage and ambient temperature increased.

An electrical impedance tomography (EIT) multi-electrode needle-probe device for local assessment of heterogeneous tissue impeditivity.

Science.gov (United States)

Meroni, Davide; Maglioli, Camilla Carpano; Bovio, Dario; Greco, Francesco G; Aliverti, Andrea

2017-07-01

Electrical Impedance Tomography (EIT) is an image reconstruction technique applied in medicine for the electrical imaging of living tissues. In literature there is the evidence that a large resistivity variation related to the differences of the human tissues exists. As a result of this interest for the electrical characterization of the biological samples, recently the attention is also focused on the identification and characterization of the human tissue, by studying the homogeneity of its structure. An 8 electrodes needle-probe device has been developed with the intent of identifying the structural inhomogeneities under the surface layers. Ex-vivo impeditivity measurements, by placing the needle-probe in 5 different patterns of fat and lean porcine tissue, were performed, and impeditivity maps were obtained by EIDORS open source software for image reconstruction in electrical impedance. The values composing the maps have been analyzed, pointing out a good tissue discrimination, and the conformity with the real images. We conclude that this device is able to perform impeditivity maps matching to reality for position and orientation. In all the five patterns presented is possible to identify and replicate correctly the heterogeneous tissue under test. This new procedure can be helpful to the medical staff to completely characterize the biological sample, in different unclear situations.

Electroencephalogram measurement using polymer-based dry microneedle electrode

Science.gov (United States)

Arai, Miyako; Nishinaka, Yuya; Miki, Norihisa

2015-06-01

In this paper, we report a successful electroencephalogram (EEG) measurement using polymer-based dry microneedle electrodes. The electrodes consist of needle-shaped substrates of SU-8, a silver film, and a nanoporous parylene protective film. Differently from conventional wet electrodes, microneedle electrodes do not require skin preparation and a conductive gel. SU-8 is superior as a structural material to poly(dimethylsiloxane) (PDMS; Dow Corning Toray Sylgard 184) in terms of hardness, which was used in our previous work, and facilitates the penetration of needles through the stratum corneum. SU-8 microneedles can be successfully inserted into the skin without breaking and could maintain a sufficiently low skin-electrode contact impedance for EEG measurement. The electrodes successfully measured EEG from the frontal pole, and the quality of acquired signals was verified to be as high as those obtained using commercially available wet electrodes without any skin preparation or a conductive gel. The electrodes are readily applicable to record brain activities for a long period with little stress involved in skin preparation to the users.

Efficacy of transgene expression in porcine skin as a function of electrode choice

DEFF Research Database (Denmark)

Gothelf, A; Mahmood, Faisal; Dagnaes-Hansen, Frederik

2011-01-01

, have mainly been performed in rodents and the body of evidence on electrode choice and optimal pulsing conditions is limited. We therefore tested plate and needle electrodes in vivo in porcine skin, which resembles human skin in structure. The luciferase (pCMV-Luc) gene was injected intradermally...... and subsequently electroporated. Simultaneously, studies with gene electrotransfer to porcine skin using plasmids coding for green fluorescent protein (GFP) and betagalactosidase were performed. Interestingly, we found needle electrodes to be more efficient than plate electrodes (p...

Needle counter

International Nuclear Information System (INIS)

Fujita, Yuzo

1977-01-01

Needle counter had been devised by Geiger about 60 years ago before the present GM counter appeared. It is suitable for the detection of weak radiation because it is limited in effective volume, if the background due to mainly cosmic ray is proportional to the effective volume of the counter. Recently the very low β detector having a needle counter as the main detector has been developed. It showed highly excellent performance in the measurements of small area samples, about ten times sensitive as compared with other detectors. The counter is installed in the very low radiation measuring well at Nokogiriyama, Chiba Prefecture, using a NaI scintillator as its guard counter. D. H. Wilkinson first treated a gas amplification counter theoretically and quantitatively. The authors have obtained good results in the comparison with the experiments of the counter using a generalized form of Wilkinson theory. The findings obtained through this study seem to be applicable to the electrode arrangement which is important for the counter design. It was found that the excellent rise time of induced pulses in a gas amplification counter was achieved in larger amplification factor and smaller convolution effect. In the detection of charged particles with small obstructing capability such as γ ray, faster rise time and higher pulses can be obtained with needle counters than wire counters. (Wakatsuki, Y.)

Oxygen tension in human tumours measured with polarographic needle electrodes and its relationship to vascular density, necrosis and hypoxia

International Nuclear Information System (INIS)

Lyng, Heidi; Sundfoer, Kolbein; Rofstad, Einar K.

1997-01-01

Background and purpose: The use of polarographic needle electrodes for measurement of oxygen tension (pO 2 ) in tumours requires documentation of the validity of the method. In the present work the pO 2 values measured polarographically with the Eppendorf pO 2 histograph in human tumours were compared with the histological appearance of the tumour tissue, i.e. vascular density, fraction of necrosis and fraction of hypoxic tissue, to investigate whether the measurements reflected the expected pO 2 . Materials and methods: The pO 2 was measured in cervix tumours in patients and in human melanoma xenografted tumours in athymic mice. Vascular density was determined in the cervix tumours by histological analysis of biopsies from the pO 2 measurement tracks. Fraction of necrosis and fraction of hypoxic tissue, i.e. tissue binding the hypoxia marker pimonidazole, were determined in the melanomas by analysis of histological sections from the tumour planes in which the pO 2 measurements were performed. Results: The pO 2 distributions showed large intratumour heterogeneity. In cervix tumours, tumour regions with vascular density (vascular length per unit tissue volume) in the range of 47-77 mm/mm 3 showed higher pO 2 than tumour regions with vascular density in the range of 20-47 mm/mm 3 , which in turn showed higher pO 2 than tumour regions with vascular density in the range of 0-20 mm/mm 3 . In melanomas, tumour regions in which necrosis and hypoxia constituted more than 50% of the tissue showed lower pO 2 than other tumour regions. Conclusions: The pO 2 measured in the tumours was consistent with the histological appearance of the tissue in which the measurements were performed, suggesting that reliable pO 2 distributions of tumours can be obtained with polarographic needle electrodes

Electrochemical Determination of Brilliant Blue and Tartrazine Based on an Ionic Liquid-Modified Expanded Graphite Paste Electrode.

Science.gov (United States)

Wang, Wenchang; Chen, Ye; Zhang, Jing; Wang, Xue; Chen, Zhidong

2015-01-01

A sensitive electrochemical method was developed for the simultaneous determination of Brilliant Blue (BB) and tartrazine (Tz) using an ionic liquid-modified expanded graphite paste electrode (IL-EGPE). The IL-EGPE was prepared by mixing ionic liquid-expanded graphite composite (IL-EG) with solid paraffin. Compared with the EGPE, the IL-EGPE remarkably enhanced the electrocatalytic oxidation signals of BB and Tz. Under optimal experimental conditions, the designed IL-EGPE exhibited wide linear responses to BB and Tz ranging from 5.0×10(-9) to 4.0×10(-6) M and 1.0×10(-8) to 1.0×10(-6) M, respectively. The detection limits for BB and Tz were 2.0×10(-9) M (1.6 ng/mL) and 3.3×10(-9) M (1.8 ng/mL) at an S/N of 3, respectively. This electrode showed good reproducibility, stability, and reusability. The proposed method was successfully applied in the simultaneous determination of BB and Tz in a soft drink with satisfactory results.

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.

Temporal and spatial evolution of EHD particle flow onset in air in a needle-to-plate negative DC corona discharge

International Nuclear Information System (INIS)

Mizeraczyk, J; Berendt, A; Podlinski, J

2016-01-01

In this paper we present images showing the temporal and spatial evolution of the electrohydrodynamic (EHD) flow of dust particles (cigarette smoke) suspended in still air in a needle-to-plate negative DC corona discharge arrangement just after the corona onset, i.e. in the first stage of development of the EHD particle flow. The experimental apparatus for our study of the EHD flow onset consisted of a needle-to-plate electrode arrangement, high voltage power supply and time-resolved EHD imaging system based on 2D time-resolved particle image velocimetry equipment. The time-resolved flow images clearly show the formation of a ball-like flow structure at the needle tip just after the corona discharge onset, and its evolution into a mushroom-like object moving to the collecting electrode. After a certain time, when the mushroom-like object is still present in the interelectrode gap a second mushroom-like object forms near the needle electrode and starts to move towards the collecting electrode. Before the first mushroom-like object reaches the collecting electrode several similar mushroom-like objects can be formed and presented simultaneously in the interelectrode gap. They look like a series of mushroom-like minijets shot from the needle electrode vicinity towards the collecting electrode. The simultaneous presence of mushroom-like minijets in the interelectrode gap in the corona discharge in particle-seeded air resembles the negative-ion-charged ‘clouds’ (induced by the Trichel pulses) traversing simultaneously the interelectrode gap of the corona discharge in air, predicted a long time ago by Loeb, and Lama and Gallo and recently by Dordizadeh et al . Analysing the time behaviours of the mushroom-like minijets and current waveform in the corona discharge in particle-seeded air, we found that the Trichel pulse trains, formed just after the corona onset initiates the mushroom-like minijets. The first stage of development of the EHD particle flow, the area of

The Electrode Modality Development in Pulsed Electric Field Treatment Facilitates Biocellular Mechanism Study and Improves Cancer Ablation Efficacy.

Science.gov (United States)

Cen, Chao; Chen, Xinhua

2017-01-01

Pulsed electric field treatment is now widely used in diverse biological and medical applications: gene delivery, electrochemotherapy, and cancer therapy. This minimally invasive technique has several advantages over traditional ablation techniques, such as nonthermal elimination and blood vessel spare effect. Different electrodes are subsequently developed for a specific treatment purpose. Here, we provide a systematic review of electrode modality development in pulsed electric field treatment. For electrodes invented for experiment in vitro, sheet electrode and electrode cuvette, electrodes with high-speed fluorescence imaging system, electrodes with patch-clamp, and electrodes with confocal laser scanning microscopy are introduced. For electrodes invented for experiment in vivo, monopolar electrodes, five-needle array electrodes, single-needle bipolar electrode, parallel plate electrodes, and suction electrode are introduced. The pulsed electric field provides a promising treatment for cancer.

The glucose enzyme electrode: is simple peroxide detection at a needle sensor acceptable?

Science.gov (United States)

Vadgama, P; Mullen, W; Churchouse, S; Battersby, C

1988-01-01

Needle type devices have been fabricated based on Pt anodes (to detect H2O2) mounted with stainless steel needles to act as the reference. Coating of these devices with glucose oxidase allowed glucose measurement, but with high dependence on stirring and background pO2 levels as well as a restricted glucose assay range. By wet dipcoating of microporous polyurethane or the application of preformed porous membranes, the linear range has been extended up to 70 mM glucose, to give minimal pO2 dependence and insensitivity to stirring. With incorporation of polyethersulphone membranes, blood measurement was possible with high selectivity (y = 0.954x + 0.202, r = 0.991, n = 48). This establishes that simple peroxide detection at a needle sensor is acceptable, and can now be focussed on increasing biocompatibility.

Presentation of Various Tactile Sensations Using Micro-Needle Electrotactile Display.

Directory of Open Access Journals (Sweden)

Mayuko Tezuka

Full Text Available Tactile displays provoke tactile sensations by artificially stimulating tactile receptors. While many types of tactile displays have been developed, electrotactile displays that exploit electric stimulation can be designed to be thin, light, flexible and thus, wearable. However, the high voltages required to stimulate tactile receptors and limited varieties of possible sensations pose problems. In our previous work, we developed an electrotactile display using a micro-needle electrode array that can drastically reduce the required voltage by penetrating through the high-impedance stratum corneum painlessly, but displaying various tactile sensations was still a challenge. In this work, we demonstrate presentation of tactile sensation of different roughness to the subjects, which is enabled by the arrangement of the electrodes; the needle electrodes are on the fingertip and the ground electrode is on the fingernail. With this arrangement, the display can stimulate the tactile receptors that are located not only in the shallow regions of the finger but also those in the deep regions. It was experimentally revealed that the required voltage was further reduced compared to previous devices and that the roughness presented by the display was controlled by the pulse frequency and the switching time, or the stimulation flow rate. The proposed electrotactile display is readily applicable as a new wearable haptic device for advanced information communication technology.

Finite-element modelling and preliminary validation of microneedle-based electrodes for enhanced tissue electroporation.

Science.gov (United States)

Houlihan, Ruth; Grygoryev, Konstantin; Zhenfei Ning; Williams, John; Moore, Tom; O'Mahony, Conor

2017-07-01

This paper investigates the use of microneedle-based electrodes for enhanced testis electroporation, with specific application to the production of transgenic mice. During the design phase, finite-element software has been used to construct a tissue model and to compare the relative performance of electrodes employing a) conventional flat plates, b) microneedle arrays, and c) invasive needles. Results indicate that microneedle-based electrodes can achieve internal tissue field strengths which are an order of magnitude higher than those generated using conventional flat electrodes, and which are comparable to fields produced using invasive needles. Using a double-sided etching process, conductive microneedle arrays were then fabricated and used in prototype electrodes. In a series of mouse model experiments involving injection of a DNA vector expressing Green Fluorescent Protein (GFP), the performance of flat and microneedle electrodes was compared by measuring GFP expression after electroporation. The main finding, supported by experimental and simulated data, is that use of microneedle-based electrodes significantly enhanced electroporation of testis.

Nanofiber electrode and method of forming same

Energy Technology Data Exchange (ETDEWEB)

Pintauro, Peter N.; Zhang, Wenjing

2018-02-27

In one aspect, a method of forming an electrode for an electrochemical device is disclosed. In one embodiment, the method includes the steps of mixing at least a first amount of a catalyst and a second amount of an ionomer or uncharged polymer to form a solution and delivering the solution into a metallic needle having a needle tip. The method further includes the steps of applying a voltage between the needle tip and a collector substrate positioned at a distance from the needle tip, and extruding the solution from the needle tip at a flow rate such as to generate electrospun fibers and deposit the generated fibers on the collector substrate to form a mat with a porous network of fibers. Each fiber in the porous network of the mat has distributed particles of the catalyst. The method also includes the step of pressing the mat onto a membrane.

A novel DC microplasma sensor constructed in a cavity PDMS chamber with needle electrodes for fast detection of methanol-containing spirit.

Science.gov (United States)

Luo, Dai-bing; Duan, Yi-xiang; He, Yi; Gao, Bo

2014-12-12

A novel microplasma device, for the first time, was constructed in a cavity Poly (dimethylsiloxane) (PDMS) chamber with two normal syringe needles serve as both the gas channels and the electrodes. This device employs argon plasma with direct current for molecular fragmentation and excitation. The microplasma is generated at atmospheric pressure in the PDMS chamber of 0.5 mL (5 × 10 × 10 mm(3)) volume with a sealable plug. Since the microplasma is maintained in a chamber by separation of the discharge zone and the substrate, stability for a long time of the microplasma is realized which could be observed by argon background emission fluctuation and SEM characterization. This property is beneficial for spectrometric detection of many volatile organics in this chamber. Besides, this kind of microplasma sensor has advantages such as flexibility in replacement of electrodes, convenience in clearance of the discharge chamber, small instrument volume, simple structure, and ease of operation. In addition, methanol-containing spirit samples were chosen to estimate the detecting performance of this microplasma for volatile organic compounds (VOCs) analysis by molecular emission spectrometry. Significant differences are observed upon the introduction of the spirit and the methanol-containing spirit samples. A detection limit of 0.3% is obtained on this microplasma device.

Oxidation of ammonium sulfite by a multi-needle-to-plate gas phase pulsed corona discharge reactor

Science.gov (United States)

Ren, Hua; Lu, Na; Shang, Kefeng; Li, Jie; Wu, Yan

2013-03-01

The oxidation of ammonium sulfite in the ammonia-based flue gas desulfurization (FGD) process was investigated in a multi-needle-to-plate gas phase pulsed corona discharge reactor in this paper. The effect of several parameters, including capacitance and peak pulse voltage of discharge system, electrode gap and bubbling gas flow rate on the oxidation rate of ammonium sulfite was reviewed. The oxidation rate of ammonium sulfite could reach 47.2% at the capacitance, the peak pulse voltage, electrode gap and bubbling gas flow rate equal to 2 nF, -24.6 k V, 35 mm and 4 L min-1 within treatment time of 40 min The experimental results indicate that the gas phase pulsed discharge system with a multi-needle-to-plate electrode can oxide the ammonium sulfite. The oxidation rate increased with the applied capacitance and peak pulse voltage and decreased with the electrode gap. As the bubbling gas flow rate increased, the oxidation rate increased first and then tended to reach a stationary value. These results would be important for the process optimization of the (NH4)2SO3 to (NH4)2SO4 oxidation.

A trucut biopsy needle for bipolar radiofrequency ablation of needle tract: a proof-of-concept experiment.

Science.gov (United States)

Bruners, Philipp; Penzkofer, Tobias; Isfort, Peter; Pfeffer, Jochen; Schmitz-Rode, Thomas; Günther, Rolf W; Mahnken, Andreas H

2010-08-01

To develop a trucut biopsy needle featuring two electrodes that allow for bipolar radiofrequency (RF) coagulation of the puncture tract. We modified a 14-G trucut biopsy needle to contain two insulated electrodes and connected the device to an RF generator. Biopsies in ex vivo porcine liver and kidney were performed. The puncture tract was coagulated by using different RF energy settings (5 W, 10 W, 20 W). Tissue specimens were dissected along the puncture tract and the coagulation area was macroscopically evaluated. CT-guided in vivo liver and kidney biopsies were performed in two domestic pigs. Lengths of specimens were measured. Post-biopsy contrast-enhanced CT examinations were performed to rule out biopsy-related bleeding. Animals were euthanised and coagulation areas macroscopically explored. The mean diameters of the coagulated area around the ex vivo biopsy tract were 4.2 +/- 1.1 mm (5 W), 6.0 +/- 2.0 mm (10 W) and 5.2 +/- 0.51 mm (20 W) in liver and 5.0 +/- 0.7 mm (5 W), 6.6 +/- 0.9 (10 W) and 6.0 +/- 2.0 mm (20 W) in kidney. After biopsies CT revealed no bleeding. Mean maximum coagulation diameters were 10.1 +/- 4.6 mm (10 W) in liver and 6.0 +/- 2.5 mm (10 W) in kidney. Mean length of the specimens was 12.2 +/- 4.4 mm in kidney and 11.1 +/- 3.6 mm in liver tissue. Bipolar RF biopsy is a promising tool for tract coagulation after percutaneous biopsy.

A trucut biopsy needle for bipolar radiofrequency ablation of needle tract: a proof-of-concept experiment

International Nuclear Information System (INIS)

Bruners, Philipp; Penzkofer, Tobias; Isfort, Peter; Pfeffer, Jochen; Schmitz-Rode, Thomas; Guenther, Rolf W.; Mahnken, Andreas H.

2010-01-01

To develop a trucut biopsy needle featuring two electrodes that allow for bipolar radiofrequency (RF) coagulation of the puncture tract. We modified a 14-G trucut biopsy needle to contain two insulated electrodes and connected the device to an RF generator. Biopsies in ex vivo porcine liver and kidney were performed. The puncture tract was coagulated by using different RF energy settings (5 W, 10 W, 20 W). Tissue specimens were dissected along the puncture tract and the coagulation area was macroscopically evaluated. CT-guided in vivo liver and kidney biopsies were performed in two domestic pigs. Lengths of specimens were measured. Post-biopsy contrast-enhanced CT examinations were performed to rule out biopsy-related bleeding. Animals were euthanised and coagulation areas macroscopically explored. The mean diameters of the coagulated area around the ex vivo biopsy tract were 4.2 ± 1.1 mm (5 W), 6.0 ± 2.0 mm (10 W) and 5.2 ± 0.51 mm (20 W) in liver and 5.0 ± 0.7 mm (5 W), 6.6 ± 0.9 (10 W) and 6.0 ± 2.0 mm (20 W) in kidney. After biopsies CT revealed no bleeding. Mean maximum coagulation diameters were 10.1 ± 4.6 mm (10 W) in liver and 6.0 ± 2.5 mm (10 W) in kidney. Mean length of the specimens was 12.2 ± 4.4 mm in kidney and 11.1 ± 3.6 mm in liver tissue. Bipolar RF biopsy is a promising tool for tract coagulation after percutaneous biopsy. (orig.)

Enhanced specific capacitance of modified needle cokes by controlling oxidation treatment

International Nuclear Information System (INIS)

Yang, Sunhye; Kim, Ick-Jun; Choi, In-Sik; Soo Kim, Hyun; Tack Kim, Yu

2010-01-01

The electric double-layer performance of needle cokes can be affected by the morphology of structures. Hence, we introduce modified needle cokes by using simple oxidation treatment. The degree of graphitization with high specific capacitance is controlled by acid and heat treatment. The active sites of cokes are increased with increasing oxidation time. Dilute nitric acid (HNO 3 ) and sodium chlorate (NaClO 3 ) are used for the activation of cokes. In this case, the interlayer distance is dramatically increased from 3.5 to 8.9 A. The specific capacitances are 33 F g -1 and 30 F ml -1 , respectively, on a two-electrode system with a potential range of 0-2.5 V. The behaviors of double-layer capacitance are demonstrated by the charge-discharge process and the morphologies of modified needle cokes are analyzed by XRD, FE-SEM, BET and elemental analysis.

Bone biopsy needles. Mechanical properties, needle design and specimen quality

International Nuclear Information System (INIS)

Keulers, Annika; Penzkofer, T.; Cunha-Cruz, V.C.; Bruners, P.; Helmholtz Inst. fuer biomedizinische Technik, Aachen; Braunschweig, T.; Schmitz-Rode, T.; Mahnken, A.; Helmholtz Inst. fuer biomedizinische Technik, Aachen

2011-01-01

To quantitatively analyze differences in mechanical properties, needle design including signs of wear, subjective handling and specimen quality of bone biopsy needles. Materials and Methods: In this study 19 different bone biopsy systems (total 38; 2 /type) were examined. With each biopsy needle five consecutive samples were obtained from vertebral bodies of swine. During puncture a force-torques sensor measured the mechanical properties and subjective handling was assessed. Before and after each biopsy the needles were investigated using a profile projector and signs of wear were recorded. Afterwards, a pathologist semi-quantitatively examined the specimen regarding sample quality. The overall evaluation considered mechanical properties, needle wear, subjective handling and sample quality. Differences were assessed for statistical significance using ANOVA and t-test. Results: Needle diameter (p = 0.003) as well as needle design (p = 0.008) affect the mechanical properties significantly. Franseen design is significantly superior to other needle designs. Besides, length reduction recorded by the profile projector, as a quality criterion showed notable distinctions in between the needle designs. Conclusion: Bone biopsy needles vary significantly in performance. Needle design has an important influence on mechanical properties, handling and specimen quality. Detailed knowledge of those parameters would improve selecting the appropriate bone biopsy needle. (orig.)

Effect of electrode and interface oxide on the property of ReRAM composed of Pr0.7Ca0.3MnO3

International Nuclear Information System (INIS)

Kaji, H; Kondo, H; Fujii, T; Arita, M; Takahashi, Y

2010-01-01

The current-voltage (I-V) characteristics of resistance random access memories (ReRAM) composed of the [top electrode] /Pr 0.7 Ca 0.3 MnO 3 (PCMO)/Pt structure were investigated by using Au, Pt, Ag, Cr, Mo and W needles as top electrodes against the PCMO layer. Reproducible resistance switching can be recognized in devices using Cr, Mo and W. Devices using Mo and W electrode showed two type of characteristics: (A) resistance change from low resistance state to high resistance state by positive bias voltage and (B) vice versa. Since the surfaces of these needles may be oxidized, we took account of the effect by the surface oxide. To check this assumption, we annealed the W needles and Mo needles in air and investigated I-V characteristics without the PCMO layer. As a result, the characteristic-(B) was classified to be induced by a surface oxide. Meanwhile, the characteristic-(A) is from PCMO. The existence of the interface oxide between top electrode and PCMO seems to decide the type of characteristics and to influence the reproducibility of the ReRAM property.

Presentation of a needle for direct or percutaneous myocardium stem cells injection

Directory of Open Access Journals (Sweden)

Nathan Valle Soubihe Junior

2013-09-01

Full Text Available The instrument has a locking mechanism and is composed of an external needle with blunt tip, with multiple 0.5 mm diameter holes. Internally it is fitted with a mandrill needle, which can be mobilized inside occluding or releasing the lateral holes. The procedure for producing micro lesions is done by exchanging the blunt mandrill for a brush-mandrill, provided with micro bristles that are structurally designed to fill the holes with small exteriorization of bristles. As an option to brush mandrill there is a second self-expandable feather shaped mandrill.

Needle Decompression in Appalachia Do Obese Patients Need Longer Needles?

Directory of Open Access Journals (Sweden)

Carter, Thomas Edward

2013-11-01

Full Text Available Introduction: Needle decompression of a tension pneumothorax can be a lifesaving procedure. It requires an adequate needle length to reach the chest wall to rapidly remove air. With adult obesity exceeding one third of the United States population in 2010, we sought to evaluate the proper catheter length that may result in a successful needle decompression procedure. Advance Trauma Life Support (ATLS currently recommends a 51 millimeter (mm needle, while the needles stocked in our emergency department are 46 mm. Given the obesity rates of our patient population, we hypothesize these needles would not have a tolerable success rate of 90%. Methods: We retrospectively reviewed 91 patient records that had computed tomography of the chest and measured the chest wall depth at the second intercostal space bilaterally. Results: We found that 46 mm needles would only be successful in 52.7% of our patient population, yet the ATLS recommended length of 51 mm has a success rate of 64.8%. Therefore, using a 64 mm needle would be successful in 79% percent of our patient population. Conclusion: Use of longer length needles for needle thoracostomy is essential given the extent of the nation’s adult obesity population. [West J Emerg Med. 2013;14(6:650-652.

Does a paresthesia during spinal needle insertion indicate intrathecal needle placement?

Science.gov (United States)

Pong, Ryan P; Gmelch, Benjamin S; Bernards, Christopher M

2009-01-01

Paresthesias are relatively common during spinal needle insertion, however, the clinical significance of the paresthesia is unknown. A paresthesia may result from needle-to-nerve contact with a spinal nerve in the epidural space, or, with far lateral needle placement, may result from contact with a spinal nerve within the intervertebral foramen. However, it is also possible and perhaps more likely, that paresthesias occur when the spinal needle contacts a spinal nerve root within the subarachnoid space. This study was designed to test this latter hypothesis. Patients (n = 104) scheduled for surgery under spinal anesthesia were observed during spinal needle insertion. If a paresthesia occurred, the needle was fixed in place and the stylet removed to observe whether cerebrospinal fluid (CSF) flowed from the hub. The presence of CSF was considered proof that the needle had entered the subarachnoid space. Paresthesias occurred in 14/103 (13.6%) of patients; 1 patient experienced a paresthesia twice. All paresthesias were transient. Following a paresthesia, CSF was observed in the needle hub 86.7% (13/15) of the time. Our data suggest that the majority of transient paresthesias occur when the spinal needle enters the subarachnoid space and contacts a spinal nerve root. Therefore, when transient paresthesias occur during spinal needle placement it is appropriate to stop and assess for the presence of CSF in the needle hub, rather than withdraw and redirect the spinal needle away from the side of the paresthesia as some authors have suggested.

Analysis of a Steerable Needle for Fine Needle Aspiration and Biopsy: Efficiency and Radiation Dose Compared With a Conventional Straight Needle.

Science.gov (United States)

Rutigliano, Sandra; Abraham, John A; Kenneally, Barry E; Zoga, Adam C; Nevalainen, Mika; Roedl, Johannes B

Percutaneous computed tomography (CT)-guided needle biopsy has proven to be an efficacious method for sampling of many soft tissue lesions, especially deep-seated masses in the abdomen and pelvis. This study sought to test the potential for a novel steerable needle to improve localization and to reduce procedure duration and radiation dose compared with a conventional straight needle. A fresh, raw meat sample (lean bovine flank) was imbedded with cylindrical radiopaque and radiolucent obstacles designed to simulate vessels (radiolucent objects) and bones (radiopaque objects) on CT. A pit-containing olive (partially radiopaque) was imbedded beyond the obstacles to represent the target. Two sites on the surface of the meat were selected and marked to determine initial needle placement. Two radiologists with different levels of experience proceeded to position a straight needle and the steerable needle from each skin site to the target using CT guidance as efficiently as possible, avoiding the obstacles. The total positioning time, the number of CT scans required for positioning, and the number of repositioning events (partial withdrawal followed by advancement) were tracked for the straight and steerable needles. For the straight needle, total time to reach the target was 499 to 667 seconds (mean, 592 seconds); for the steerable needle, total time to reach the target was 281 to 343 seconds (mean, 309 seconds), on average, 48% lower. The number of CT scans needed for needle positioning averaged 6.25 for the straight needle and 3.5 for the steerable needle, which is 44% lower. Repositioning events (withdrawing and readvancing the needle) ranged from 3 to 10 for the straight needle (mean, 6.5) and 0 for the steerable needle. Using an in vitro model embedded with obstacles, the steerable needle performed better than a straight needle with regard to procedure time, needle repositioning events, and CT scans required for placement.

TU-H-CAMPUS-JeP3-05: Adaptive Determination of Needle Sequence HDR Prostate Brachytherapy with Divergent Needle-By-Needle Delivery

International Nuclear Information System (INIS)

Borot de Battisti, M; Maenhout, M; Lagendijk, J J W; Van Vulpen, M; Moerland, M A; Denis de Senneville, B; Hautvast, G; Binnekamp, D

2016-01-01

Purpose: To develop a new method which adaptively determines the optimal needle insertion sequence for HDR prostate brachytherapy involving divergent needle-by-needle dose delivery by e.g. a robotic device. A needle insertion sequence is calculated at the beginning of the intervention and updated after each needle insertion with feedback on needle positioning errors. Methods: Needle positioning errors and anatomy changes may occur during HDR brachytherapy which can lead to errors in the delivered dose. A novel strategy was developed to calculate and update the needle sequence and the dose plan after each needle insertion with feedback on needle positioning errors. The dose plan optimization was performed by numerical simulations. The proposed needle sequence determination optimizes the final dose distribution based on the dose coverage impact of each needle. This impact is predicted stochastically by needle insertion simulations. HDR procedures were simulated with varying number of needle insertions (4 to 12) using 11 patient MR data-sets with PTV, prostate, urethra, bladder and rectum delineated. Needle positioning errors were modeled by random normally distributed angulation errors (standard deviation of 3 mm at the needle’s tip). The final dose parameters were compared in the situations where the needle with the largest vs. the smallest dose coverage impact was selected at each insertion. Results: Over all scenarios, the percentage of clinically acceptable final dose distribution improved when the needle selected had the largest dose coverage impact (91%) compared to the smallest (88%). The differences were larger for few (4 to 6) needle insertions (maximum difference scenario: 79% vs. 60%). The computation time of the needle sequence optimization was below 60s. Conclusion: A new adaptive needle sequence determination for HDR prostate brachytherapy was developed. Coupled to adaptive planning, the selection of the needle with the largest dose coverage impact

Water Treatment Using Plasma Discharge with Variation of Electrode Materials

Science.gov (United States)

Chanan, N.; Kusumandari; Saraswati, T. E.

2018-03-01

This research studied water treatment using plasma discharge. Plasma generated in this study produced active species that played a role in organic compound decomposition. The plasma reactor consisted of two needle electrodes made from stainless steel, tungsten, aluminium and grafit. It placed approximately 2 mm above the solution and connected with high-AC voltage. A solution of methylene blue used as an organic solution model. Plasma treatment times were 2, 4, 6, 8 and 10 min. The absorbance, temperature and pH of the solution were measured before and after treatment using various electrodes. The best electrode used in plasma discharging for methylene blue absorbance reduction was the graphite electrode, which provided the highest degradation efficiency of 98% at 6 min of treatment time.

The efficacy of two electrodes radiofrequency technique: comparison study using a cadaveric interspinous ligament and temperature measurement using egg white.

Science.gov (United States)

Lee, Chang-Hyung; Derby, Richard; Choi, Hyun-Seok; Lee, Sang-Heon; Kim, Se Hoon; Kang, Yoon Kyu

2010-01-01

One technique in radiofrequency neurotomies uses 2 electrodes that are simultaneously placed to lie parallel to one another. Comparing lesions on cadaveric interspinous ligament tissue and measuring the temperature change in egg white allows us to accurately measure quantitatively the area of the lesion. Fresh cadaver spinal tissue and egg white tissue were used. A series of samples were prepared with the electrodes placed 1 to 7 mm apart. Using radiofrequency, the needle electrodes were heated in sequential or simultaneous order and the distance of the escaped lesion area and temperature were measured. Samples of cadaver interspinous ligament showed sequential heating of the needles limits the placement of the needle electrodes up to 2 mm apart from each other and up to 4 mm apart when heated simultaneously. The temperature at the escaped lesion area decreased according to the distance for egg white. There was a significant difference in temperature at the escaped lesion area up to 6 mm apart and the temperature was above 50 degrees celsius up to 5 mm in simultaneous lesion and 3 mm in the sequential lesion. The limitations of this study include cadaveric experimentation and use of intraspinous ligament rather than medial branch of the dorsal ramus which is difficult to identify. Heating the 2 electrodes simultaneously appears to coagulate a wider area and potentially produce better results in less time.

Sharing of Needles and Syringes among Men Who Inject Drugs: HIV Risk in Northwest Bangladesh.

Directory of Open Access Journals (Sweden)

M Kamal Pasa

Full Text Available Injection drug use is prevalent in northwestern Bangladesh. We sought to explore the context of needle/syringe sharing among persons who inject drugs (PWID, examining risk exposures to blood-borne infections like the human immunodeficiency virus (HIV and hepatitis in a region where these dual epidemics are likely to expand.We used a qualitative research approach to learn about injection practices, conducting 60 in-depth interviews among PWID. We then conducted 12 focus group discussions (FGDs that generated a checklist of salient issues, and followed up with personal observations of typical days at the drug-use venues. Content and interpretative frameworks were used to analyze qualitative information and socio-demographic information, using SPSS software.We found that needle/syringe-sharing behaviours were integrated into the overall social and cultural lives of drug users. Sharing behaviours were an central component of PWID social organization. Sharing was perceived as an inherent element within reciprocal relationships, and sharing was tied to beliefs about drug effects, economic adversity, and harassment due to their drug user status. Carrying used needles/syringes to drug-use venues was deemed essential since user-unfriendly needle-syringe distribution schedules of harm reduction programmes made it difficult to access clean needles/syringes in off-hours. PWID had low self-esteem. Unequal power relationships were reported between the field workers of harm reduction programmes and PWID. Field workers expressed anti-PWID bias and judgmental attitudes, and also had had misconceptions about HIV and hepatitis transmission. PWID were especially disturbed that no assistance was forthcoming from risk reduction programme staff when drug users manifested withdrawal symptoms.Interventions must take social context into account when scaling up programmes in diverse settings. The social organization of PWID include values that foster needle

[Discussion on needling sensation, arrival of qi and needling response (Deqi)].

Science.gov (United States)

Zhang, Fang; Wang, Hong-Du

2012-12-01

The current appointed teaching material of Science of Acupuncture and Moxibustion holds that there is no difference among the needling sensation, arrival of qi and needling response. However, the author has a different understanding. Therefore, Neijing (Internal Classic), its annotation, exposition and understandings of ancient and modern famous experts are cited to analyze their meanings. And the result indicates that the needling sensation is subjective feelings and perceived responses of doctors and patients. Arrival of qi is the healing process of the organ through activating the anti-pathogenic qi to expel the pathogens. The needling response is the final aim of acupuncture therapy. Thus, the meaning of needling sensation, arrival of qi, and needling response are different. And an accurate understanding can better guide acupuncture treatment.

Geographical and climatic limits of needle types of one- and two-needled pinyon pines

Science.gov (United States)

Cole, K.L.; Fisher, J.; Arundel, S.T.; Cannella, J.; Swift, S.

2008-01-01

Aim: The geographical extent and climatic tolerances of one- and two-needled pinyon pines (Pinus subsect. Cembroides) are the focus of questions in taxonomy, palaeoclimatology and modelling of future distributions. The identification of these pines, traditionally classified by one- versus two-needled fascicles, is complicated by populations with both one- and two-needled fascicles on the same tree, and the description of two more recently described one-needled varieties: the fallax-type and californiarum-type. Because previous studies have suggested correlations between needle anatomy and climate, including anatomical plasticity reflecting annual precipitation, we approached this study at the level of the anatomy of individual pine needles rather than species. Location: Western North America. Methods: We synthesized available and new data from field and herbarium collections of needles to compile maps of their current distributions across western North America. Annual frequencies of needle types were compared with local precipitation histories for some stands. Historical North American climates were modelled on a c. 1-km grid using monthly temperature and precipitation values. A geospatial model (ClimLim), which analyses the effect of climate-modulated physiological and ecosystem processes, was used to rank the importance of seasonal climate variables in limiting the distributions of anatomical needle types. Results: The pinyon needles were classified into four distinct types based upon the number of needles per fascicle, needle thickness and the number of stomatal rows and resin canals. The individual needles fit well into four categories of needle types, whereas some trees exhibit a mixture of two needle types. Trees from central Arizona containing a mixture of Pinus edulis and fallax-type needles increased their percentage of fallax-type needles following dry years. All four needle types occupy broader geographical regions with distinctive precipitation regimes

Relations between Scots pine needle element concentrations and decreased needle longevity along pollution gradients

International Nuclear Information System (INIS)

Lamppu, Jukka; Huttunen, Satu

2003-01-01

Deceased needle longevity was related to increased heavy metal concentrations. - Scots pine (Pinus sylvestris L.) shoots were sampled along transects near one urban pollution source and two smelters. Needle Mg, P and K concentrations decreased from the second to the fourth age class linearly with needle survival along the urban pollution gradient. Still, over 80% of the average concentration of these nutrients remained in the fourth needle age class. Decreased needle longevity was closely related to the increased heavy metal concentrations near the smelters. Near the urban pollution source, it was related to the increased annual needle mass and the increased needle nutrient concentrations. Decreased Mn accumulation along with needle age was detected near all pollution sources. Leaching of Mn from needles and especially from soil as a cause of decreased needle concentrations is discussed

Transbronchial needle aspiration with a new electromagnetically-tracked TBNA needle

Science.gov (United States)

Choi, Jae; Popa, Teo; Gruionu, Lucian

2009-02-01

Transbronchial needle aspiration (TBNA) is a common method used to collect tissue for diagnosis of different chest diseases and for staging lung cancer, but the procedure has technical limitations. These limitations are mostly related to the difficulty of accurately placing the biopsy needles into the target mass. Currently, pulmonologists plan TBNA by examining a number of Computed Tomography (CT) scan slices before the operation. Then, they manipulate the bronchoscope down the respiratory track and blindly direct the biopsy. Thus, the biopsy success rate is low. The diagnostic yield of TBNA is approximately 70 percent. To enhance the accuracy of TBNA, we developed a TBNA needle with a tip position that can be electromagnetically tracked. The needle was used to estimate the bronchoscope's tip position and enable the creation of corresponding virtual bronchoscopic images from a preoperative CT scan. The TBNA needle was made with a flexible catheter embedding Wang Transbronchial Histology Needle and a sensor tracked by electromagnetic field generator. We used Aurora system for electromagnetic tracking. We also constructed an image-guided research prototype system incorporating the needle and providing a user-friendly interface to assist the pulmonologist in targeting lesions. To test the feasibility of the accuracy of the newly developed electromagnetically-tracked needle, a phantom study was conducted in the interventional suite at Georgetown University Hospital. Five TBNA simulations with a custom-made phantom with a bronchial tree were performed. The experimental results show that our device has potential to enhance the accuracy of TBNA.

Mechanics of needle-tissue interaction

NARCIS (Netherlands)

Roesthuis, Roy; van Veen, Youri; 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

Interlayer expanded molybdenum disulfide nanosheets assembly for electrochemical supercapacitor with enhanced performance

International Nuclear Information System (INIS)

Xiao, Huaqing; Wang, Shutao; Zhang, Shuo; Wang, Yihe; Xu, Qingfei; Hu, Wenjie; Zhou, Yan; Wang, Zhaojie; An, Changhua; Zhang, Jun

2017-01-01

Rational structural design for electrode materials is essential for fabricating high performance supercapacitors. In this work, we demonstrated a novel way to prepare incompact MoS_2 nanosheets assembled nanorods with the interlayer of MoS_2 nanosheets expanded to 0.89 nm, namely layer expanded MoS_2 nanorods (LE-MoS_2 NRs). The material was characterized by XRD, XPS and electron microscopes. The XRD data and HRTEM images confirmed the existence of expanded interlayer of MoS_2 nanosheets. N_2 adsorption-desorption isotherms of LE-MoS_2 NRs indicated high specific area up to 37.0 m"2 g"−"1. It was found that the expanded interlayer spacing can benefit the ion transportation within the MoS_2 interlayers. The as-prepared electrode material showed capacitance up to 231 F g"−"1 at 1 A g"−"1 charge-discharge current and cycling stability test indicated high capacitance of 177 F g"−"1 was retained after 1000 cycles. - Highlights: • High performance electrochemical supercapacitor electrode material. • Interlayer expanded MoS_2 to achieve enhanced capacitance. • Facile hydrothermal synthesis of interlayer expanded MoS_2. • MoS_2 nanosheets assembled incompact nanorods.

Evaluation of a needle social marketing strategy to control HIV among injecting drug users in China.

Science.gov (United States)

Wu, Zunyou; Luo, Wei; Sullivan, Sheena G; Rou, Keming; Lin, Peng; Liu, Wei; Ming, Zhongqiang

2007-12-01

To evaluate the effectiveness of a needle social marketing strategy to reduce needle sharing and hepatitis C Virus (HCV)/HIV transmission among injecting drug users (IDU) in China. Two-armed, prospective, community-randomized prevention trial. Four counties/townships in Guangxi and Guangdong provinces; one randomized to intervention the other to control in each province. Injecting drug users: 823 (443 intervention, 382 control) at baseline and 852 (415 intervention, 407 control) at the second cross-sectional survey 12 months later. A needle social marketing programme, including promotion of safe injection norms and increased access to clean needles over a 12 month period. Cross sectional surveys at baseline and follow-up compared changes in drug using behaviours and HIV and HCV rates in the intervention and control communities. Needle sharing behaviours were similar in the two groups at baseline (68.4 vs. 67.8%), and dropped significantly to 35.3% in the intervention community and remained relatively stable in the control community (62.3%; P marketing can reduce risky injecting behaviour and HIV/HCV transmission among injecting drug users in China and should be expanded.

Investigating the Effects of Three Needling Parameters (Manipulation, Retention Time, and Insertion Site) on Needling Sensation and Pain Profiles: A Study of Eight Deep Needling Interventions

Science.gov (United States)

Loyeung, Bertrand Y. K.; Cobbin, Deirdre M.

2013-01-01

Introduction. In traditional Chinese acupuncture, needle sensation (deqi) is purported to contribute to a therapeutic outcome. While researchers have attempted to define deqi qualitatively, few have examined the effects of needling parameters on its intensity. Methods. 24 healthy subjects completed eight interventions scheduled at least one week apart, which involved manual acupuncture to LI4 or a designated nonacupoint (NAP) on the hand, with real or simulated manipulation each three minutes and needle retentions of one or 21 minutes. Intensities of needling sensation and pain were reported every three minutes and sensation qualities were reported post-intervention. Results. Immediately after needle insertion, similar levels of mean needle sensation and of pain were reported independent of intervention. At subsequent measurement times, only two interventions (one at LI4 and one at NAP) maintained statistically significantly elevated needle sensation and pain scores and reported higher numbers of needle sensation descriptors. For both, the needle was retained for 21 minutes and manipulated every three minutes. Neither intervention differed significantly in terms of levels of pain, and needle sensation or numbers and qualities of needle sensation described. Conclusion. In this group of healthy subjects, the initial needling for all eight interventions elicited similar levels of needle sensation and pain. These levels were only maintained if there was ongoing of needle manipulation and retention of the needle. By contrast, the strength of needle sensation or pain experienced was independent of insertion site. PMID:24159337

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

International Nuclear Information System (INIS)

Topal, U.; Berkman, Yahya M.

2005-01-01

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 χ 2 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

Accuracy of Core Needle Biopsy Versus Fine Needle Aspiration Cytology for Diagnosing Salivary Gland Tumors

Directory of Open Access Journals (Sweden)

In Hye Song

2015-03-01

Full Text Available Background: Core needle biopsy is a relatively new technique used to diagnose salivary gland lesions, and its role in comparison with fine needle aspiration cytology needs to be refined. Methods: We compared the results of 228 ultrasound-guided core needle biopsy and 371 fine needle aspiration procedures performed on major salivary gland tumors with their postoperative histological diagnoses. Results: Core needle biopsy resulted in significantly higher sensitivity and more accurate tumor subtyping, especially for malignant tumors, than fine needle aspiration. No patient developed major complications after core needle biopsy. Conclusions: We recommend ultrasoundguided core needle biopsy as the primary diagnostic tool for the preoperative evaluation of patients with salivary gland lesions, especially when malignancy is suspected.

Interlayer expanded molybdenum disulfide nanosheets assembly for electrochemical supercapacitor with enhanced performance

Energy Technology Data Exchange (ETDEWEB)

Xiao, Huaqing; Wang, Shutao; Zhang, Shuo; Wang, Yihe; Xu, Qingfei; Hu, Wenjie [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); Zhou, Yan, E-mail: yanzhou@upc.edu.cn [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); Wang, Zhaojie [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); An, Changhua [College of Science, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China); College of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Zhang, Jun, E-mail: zhangj@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao, Shandong, 266580 (China)

2017-05-01

Rational structural design for electrode materials is essential for fabricating high performance supercapacitors. In this work, we demonstrated a novel way to prepare incompact MoS{sub 2} nanosheets assembled nanorods with the interlayer of MoS{sub 2} nanosheets expanded to 0.89 nm, namely layer expanded MoS{sub 2} nanorods (LE-MoS{sub 2} NRs). The material was characterized by XRD, XPS and electron microscopes. The XRD data and HRTEM images confirmed the existence of expanded interlayer of MoS{sub 2} nanosheets. N{sub 2} adsorption-desorption isotherms of LE-MoS{sub 2} NRs indicated high specific area up to 37.0 m{sup 2} g{sup −1}. It was found that the expanded interlayer spacing can benefit the ion transportation within the MoS{sub 2} interlayers. The as-prepared electrode material showed capacitance up to 231 F g{sup −1} at 1 A g{sup −1} charge-discharge current and cycling stability test indicated high capacitance of 177 F g{sup −1} was retained after 1000 cycles. - Highlights: • High performance electrochemical supercapacitor electrode material. • Interlayer expanded MoS{sub 2} to achieve enhanced capacitance. • Facile hydrothermal synthesis of interlayer expanded MoS{sub 2}. • MoS{sub 2} nanosheets assembled incompact nanorods.

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....

Effect of Needle Size in Ultrasound-guided Core Needle Breast Biopsy: Comparison of 14-, 16-, and 18-Gauge Needles.

Science.gov (United States)

Giuliani, Michela; Rinaldi, Pierluigi; Rella, Rossella; Fabrizi, Gina; Petta, Federica; Carlino, Giorgio; Di Leone, Alba; Mulè, Antonino; Bufi, Enida; Romani, Maurizio; Belli, Paolo; Bonomo, Lorenzo

2017-11-01

The aim of the present study was to assess the diagnostic accuracy of ultrasound-guided core needle biopsy (US-CNB) of breast lesions, comparing smaller needles (16- and 18-gauge) with the 14-gauge needle, and to analyze the lesion characteristics influencing US-CNB diagnostic performance. All the patients provided informed consent before the biopsy procedure. The data from breast lesions that had undergone US-CNB in our institution from January 2011 to January 2015 were retrospectively reviewed. The inclusion criterion was the surgical histopathologic examination findings of the entire lesion or radiologic follow-up data for ≥ 24 months. The exclusion criterion was the use of preoperative neoadjuvant therapy. The US-CNB results were compared with the surgical pathologic results or with the follow-up findings in the 3 needle size groups (14-, 16-, and 18-gauge). The needle size- and lesion characteristic-specific diagnostic accuracy parameters were evaluated. Statistical analysis was performed using a dedicated software program, and P ≤ .01 was considered significant. A total of 1118 US-CNB cases (1042 patients) were included. Of the 1118 cases, 630 (56.3%) were in the 14-gauge group, 136 (12.2%) in the 16-gauge, and 352 (31.5%) in the 18-gauge needle group. Surgery was performed on 800 lesions (71.6%). Of these, 619 were malignant, 77 were high risk, and 104 were benign. The remaining 318 lesions (28.4%) underwent follow-up imaging studies. All the lesions were stable and, therefore, were considered benign. No differences were observed in the diagnostic accuracy parameters among the 3 needle size groups (P > .01). The false-negative rate was greater for lesions  .01). US-CNB performed with small needles (16 and 18 gauge) had the same diagnostic accuracy as that performed with 14-gauge needles, regardless of the lesion characteristics. Copyright © 2017 Elsevier Inc. All rights reserved.

Long Life Nickel Electrodes for Nickel-Hydrogen Cells: Fiber Substrates Nickel Electrodes

Science.gov (United States)

Rogers, Howard H.

2000-01-01

Samples of nickel fiber mat electrodes were investigated over a wide range of fiber diameters, electrode thickness, porosity and active material loading levels. Thickness' were 0.040, 0.060 and 0.080 inches for the plaque: fiber diameters were primarily 2, 4, and 8 micron and porosity was 85, 90, and 95%. Capacities of 3.5 in. diameter electrodes were determined in the flooded condition with both 26 and 31% potassium hydroxide solution. These capacity tests indicated that the highest capacities per unit weight were obtained at the 90% porosity level with a 4 micron diameter fiber plaque. It appeared that the thinner electrodes had somewhat better performance, consistent with sintered electrode history. Limited testing with two-positive-electrode boiler plate cells was also carried out. Considerable difficulty with constructing the cells was encountered with short circuits the major problem. Nevertheless, four cells were tested. The cell with 95% porosity electrodes failed during conditioning cycling due to high voltage during charge. Discharge showed that this cell had lost nearly all of its capacity. The other three cells after 20 conditioning cycles showed capacities consistent with the flooded capacities of the electrodes. Positive electrodes made from fiber substrates may well show a weight advantage of standard sintered electrodes, but need considerably more work to prove this statement. A major problem to be investigated is the lower strength of the substrate compared to standard sintered electrodes. Problems with welding of leads were significant and implications that the electrodes would expand more than sintered electrodes need to be investigated. Loading levels were lower than had been expected based on sintered electrode experiences and the lower loading led to lower capacity values. However, lower loading causes less expansion and contraction during cycling so that stress on the substrate is reduced.

Needle-like Co3O4 anchored on the graphene with enhanced electrochemical performance for aqueous supercapacitors.

Science.gov (United States)

Guan, Qun; Cheng, Jianli; Wang, Bin; Ni, Wei; Gu, Guifang; Li, Xiaodong; Huang, Ling; Yang, Guangcheng; Nie, Fude

2014-05-28

We synthesized the needle-like cobalt oxide/graphene composites with different mass ratios, which are composed of cobalt oxide (Co3O4 or CoO) needle homogeneously anchored on graphene nanosheets as the template, by a facile hydrothermal method. Without the graphene as the template, the cobalt precursor tends to group into urchin-like spheres formed by many fine needles. When used as electrode materials of aqueous supercapacitor, the composites of the needle-like Co3O4/graphene (the mass ratio of graphene oxide(GO) and Co(NO3)2·6H2O is 1:5) exhibit a high specific capacitance of 157.7 F g(-1) at a current density of 0.1 A g(-1) in 2 mol L(-1) KOH aqueous solution as well as good rate capability. Meanwhile, the capacitance retention keeps about 70% of the initial value after 4000 cycles at a current density of 0.2 A g(-1). The enhancement of excellent electrochemical performances may be attributed to the synergistic effect of graphene and cobalt oxide components in the unique multiscale structure of the composites.

Dynamics of translational friction in needle-tissue interaction during needle insertion.

Science.gov (United States)

Asadian, Ali; Patel, Rajni V; Kermani, Mehrdad R

2014-01-01

In this study, a distributed approach to account for dynamic friction during needle insertion in soft tissue is presented. As is well known, friction is a complex nonlinear phenomenon. It appears that classical or static models are unable to capture some of the observations made in systems subjected to significant frictional effects. In needle insertion, translational friction would be a matter of importance when the needle is very flexible, or a stop-and-rotate motion profile at low insertion velocities is implemented, and thus, the system is repeatedly transitioned from a pre-sliding to a sliding mode and vice versa. In order to characterize friction components, a distributed version of the LuGre model in the state-space representation is adopted. This method also facilitates estimating cutting force in an intra-operative manner. To evaluate the performance of the proposed family of friction models, experiments were conducted on homogeneous artificial phantoms and animal tissue. The results illustrate that our approach enables us to represent the main features of friction which is a major force component in needle-tissue interaction during needle-based interventions.

Needle phobia during pregnancy.

Science.gov (United States)

Searing, Kimberly; Baukus, Mary; Stark, Mary Ann; Morin, Karen H; Rudell, Barb

2006-01-01

The objective of this study was to understand the experience of a pregnant woman with needle phobia and examine its impact on her antepartum, intrapartum, and postpartum experience. A case study format was employed. A 21-year-old primiparous woman with diagnosed needle phobia was interviewed, and her prenatal and delivery records were reviewed. Three tasks during pregnancy were identified: seeking trusting relationships with health care providers; establishing and maintaining control and understanding; and coping with fear of needles, pain, and invasion. As frequent caregivers during childbearing, nurses with an understanding of needle phobia can help to establish trusting relationships with women with this phobia and support them and their families during childbearing and their encounters with needles. (c) 2006, AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses

[Deep needling and shallow needling at three acupoints around ear for subjective tinnitus: a randomized controlled trial].

Science.gov (United States)

Yin, Tao; Ni, Jinxia; Zhu, Wenzeng

2015-10-01

To compare the effective differences between deep needling and shallow needling at three acupoints around ear for subjective tinnitus. Fifty patients with subjective tinnitus were randomized divided into a deep needling group and a shallow needling group, 25 cases in each group. Twenty-two patients in the deep needling group and 20 patients in the shallow needling group were brought into statistic in the end. In the two groups, the three acupoints around ear and distal acupoints were both selected. The acupoints of the affected side such as Yifeng (TE 17), Tinghui (GB 2), Ermen (TE 21), Zhigou (TE 6), Zhongzhu (TE 3) and Hegu (LI 4) were adopted. Yifeng (TE 17), Tinghui (GB 2) and Ermen (TE 21) were acupunctured 30-38 mm in the deep needling group and 15-20 mm in the shallow needling group. The other acupoints were conventionally acupunctured in the two groups. The needles were retained for 30 min,once a day and five times a week for all patients. The treatment was continuously for 4 weeks in the two groups. Tinnitus handicap inventory (THI) scores, tinnitus grades and visual analogue scale (VAS) for tinnitus sound levels were observed before and after treatment, and the effects of the two groups were compared. The total effective rate in the deep needling group was 59.1% (13/22), and it was better than 20.0% (4/20) in the shallow needling group (P deep needling, group, the THI score, tinnitus grade and the VAS score were improved than those before treatment (all P shallow needling group, the three above indices before and after treatment were not different in statistical significance (all P > 0.05). After treatment, all the three indices in the deep needling group were superior to those in the shallow needling group (all P shallow needling at the three acupoints.

Structures and Properties of Polyacrylonitrile/Graphene Composite Nanofiber Yarns Prepared by Multi-Needle Electrospinning Device with an Auxiliary Electrode.

Science.gov (United States)

Yan, Tao; Pan, Zhi-Juan

2018-06-01

In this paper, polyacrylonitrile/graphene composite nanofiber filaments were manufactured continuously by a homemade eight-needle electrospinning device with an auxiliary electrode. The polyacrylonitrile/graphene composite nanofiber yarns were obtained continuously by plying and twisting the composite nanofiber filaments. The structures and properties of the composite nanofiber filaments with different GP mass fractions and yarns were investigated. The results demonstrated that the maximum alignment degree of the composite nanofibers along the filament axis could reach 74.3% with 1%, and the alignment degree decreased with increasing graphene mass fraction. The diameters of the composite nanofibers were considerably smaller than those of the pure polyacrylonitrile nanofiber, and the minimum diameter was 156 nm for 1%. The conductivity of the composite nanofiber filaments was significantly enhanced by seven orders of magnitude compared with that of the pure polyacrylonitrile nanofiber filament, and the maximum value was 3.73×10-7 S/cm for 1.5%. Due to graphene agglomeration, the conductivity decreased when the mass fraction was more than 1.5%. The different number of filaments and twists were examined in detail to improve the poor mechanical properties of the nanofiber filaments. With an increase in twists, the breaking stress and strain increased initially and later decreased, and the maximum breaking stress and strain were 16.54 MPa and 26.42%, respectively. This study demonstrates the possibility of continuously and stably manufacturing polyacrylonitrile/graphene composite nanofiber yarns.

Needle bar for warp knitting machines

Science.gov (United States)

Hagel, Adolf; Thumling, Manfred

1979-01-01

Needle bar for warp knitting machines with a number of needles individually set into slits of the bar and having shafts cranked to such an extent that the head section of each needle is in alignment with the shaft section accommodated by the slit. Slackening of the needles will thus not influence the needle spacing.

A fine pointed glucose oxidase immobilized electrode for low-invasive amperometric glucose monitoring.

Science.gov (United States)

Li, Jiang; Koinkar, Pankaj; Fuchiwaki, Yusuke; Yasuzawa, Mikito

2016-12-15

A low invasive type glucose sensor, which has a sensing region at the tip of a fine pointed electrode, was developed for continuous glucose monitoring. Platinum-iridium alloy electrode with a surface area of 0.045mm(2) was settled at the middle of pointed PEEK (Polyetheretherketone) tubing and was employed as sensing electrode. Electrodeposition of glucose oxidase in the presence of surfactant, Triton X-100, was performed for high-density enzyme immobilization followed by the electropolymerization of o-phenylenediamine for the formation of functional entrapping and permselective polymer membrane. Ag/AgCl film was coated on the surface of PEEK tubing as reference electrode. Amperometric responses of the prepared sensors to glucose were measured at a potential of 0.60V (vs. Ag/AgCl). The prepared electrode showed the sensitivity of 2.55μA/cm(2) mM with high linearity of 0.9986, within the glucose concentration range up to 21mM. The detection limit (S/N=3) was determined to be 0.11mM. The glucose sensor properties were evaluated in phosphate buffer solution and in vivo monitoring by the implantation of the sensors in rabbit, while conventional needle type sensors as a reference were used. The results showed that change in output current of the proposed sensor fluctuated similar with one in output current of the conventional needle type sensors, which was also in similar accordance with actual blood sugar level measured by commercially glucose meter. One-point calibration method was used to calibrate the sensor output current. Copyright © 2016 Elsevier B.V. All rights reserved.

Rational design of new electrodes for electrochemotherapy.

Science.gov (United States)

Spugnini, E P; Citro, G; Porrello, A

2005-06-01

Electrochemotherapy associates the local delivery of anticancer drugs with the administration of permeabilizing electric pulses that support the antiblastic action. The basic instrumentation for this therapy is constituted by a pulse generator and various specific electrodes. While many efforts have been profuse by researchers in this field to obtain the standardization of the pulse generating equipment over the past 15 years, the delivery apparatus still needs refinements in order to reach most of the body districts, to control the homogeneity and stability of the electric fields and to further reduce morbidity. With the aim to develop innovative electrodes able to satisfy, at least partially, these requirements, extensive studies on pet patients with spontaneous neoplasms have been conducted, leading to the manufacturing of several different prototypes. In this paper we discuss the rationale of 11 different electrodes, briefly summarize the results obtained and their experimental validation, also presenting five paradigmatic clinical cases. In particular, it is shown that the caliper electrodes are more suited for the treatment of cutaneous and subcutaneous lesions, while the needle arrays are more efficacious in intraoperative settings. Furthermore, relevant peculiarities of unipolar electrodes are examined with a particular focus on the irregular current paths that they produce and on the potentialities of this feature. Remarkably, the decrease of the steric encumbrance turned out to be a stronger factor in electrode design than the containment of the total number of electric fields covered in serial ECT sessions. In the conclusions, perspectives and new challenges of electrode design for electrochemotherapy are illustrated.

Ultrasound-guided percutaneous treatment of hepatocellular carcinoma by radiofrequency hyperthermia with a 'cooled-tip needle'. A preliminary clinical experience.

Science.gov (United States)

Francica, G; Marone, G

1999-05-01

Radiofrequency hyperthermia using the newly-developed 'cooled-tip' needle has recently been proposed as a therapeutic modality for hepatocellular carcinoma (HCC). Herein we report our preliminary results on feasibility and effectiveness of the thermal ablation of mono- or pauci-focal hepatocellular carcinoma with the cooled-tip needle. We treated 15 cirrhotic patients (mean age 68.8 years; 12 males; 14 HCV-positive; 13 in Child's Class A and 2 in Class B) with 20 hepatocellular carcinoma nodules (mean diameter 28.1 mm; range 10-43 mm; nine lesions with diameter greater than 3 cm). None of the patients had portal thrombosis and/or extrahepatic spread. We used a radiofrequency generator (100 W of power) connected to a 18 g perfusion electrode needle with an exposed tip of 2-3 cm. The circuit was closed through a dispersive electrode positioned under the patient's thighs. A peristaltic pump infused a chilled (2-5 degrees C) saline solution to guarantee the continuous cooling of the needle tip. The needle was placed into target lesions under US guidance. The interventional procedure was carried out in general anesthesia without intubation. Dynamic helical CT was carried out 15-20 days after thermal ablation to assess therapeutic efficacy. In all, 38 areas of coagulation necrosis (at 1000-1200 mA for 10-15 min) were generated in 24 sessions in the 20 hepatocellular carcinoma nodules (mean 1.9 lesions per nodule and 1.2 sessions per nodule). Complete necrosis as assessed at dynamic CT (lack of enhancement during the arteriographic phase) was achieved in 75% of cases in a single session; after a second RF session success rate was 90% (18 out of 20 nodules). A self-limited pleurisy along with a 5-fold increase in transaminases occurred in one patient; a 3-fold elevation of transaminases was encountered in three other patients. During the follow-up (median 15 months) five patients had recurrent hepatocellular carcinoma with a 1-year disease free interval of 64%. Of the

Enhanced Cycleability of Amorphous MnO₂ by Covering on α-MnO₂ Needles in an Electrochemical Capacitor.

Science.gov (United States)

Liu, Quanbing; Ji, Shan; Yang, Juan; Wang, Hui; Pollet, Bruno G; Wang, Rongfang

2017-08-24

An allomorph MnO₂@MnO₂ core-shell nanostructure was developed via a two-step aqueous reaction method. The data analysis of Scanning Electron Microscopy, Transmission Electron Microscopy, X-Ray Diffraction and N₂ adsorption-desorption isotherms experiments indicated that this unique architecture consisted of a porous layer of amorphous-MnO₂ nano-sheets which were well grown onto the surface of α-MnO₂ nano-needles. Cyclic voltammetry experiments revealed that the double-layer charging and Faradaic pseudo -capacity of the MnO₂@MnO₂ capacitor electrode contributed to a specific capacitance of 150.3 F·g -1 at a current density of 0.1 A·g -1 . Long cycle life experiments on the as-prepared MnO₂@MnO₂ sample showed nearly a 99.3% retention after 5000 cycles at a current density of 2 A·g -1 . This retention value was found to be significantly higher than those reported for amorphous MnO₂-based capacitor electrodes. It was also found that the remarkable cycleability of the MnO₂@MnO₂ was due to the supporting role of α-MnO₂ nano-needle core and the outer amorphous MnO₂ layer.

Molybdenum coated SU-8 microneedle electrodes for transcutaneous electrical nerve stimulation.

Science.gov (United States)

Soltanzadeh, Ramin; Afsharipour, Elnaz; Shafai, Cyrus; Anssari, Neda; Mansouri, Behzad; Moussavi, Zahra

2017-11-21

Electrophysiological devices are connected to the body through electrodes. In some applications, such as nerve stimulation, it is needed to minimally pierce the skin and reach the underneath layers to bypass the impedance of the first layer called stratum corneum. In this study, we have designed and fabricated surface microneedle electrodes for applications such as electrical peripheral nerve stimulation. We used molybdenum for microneedle fabrication, which is a biocompatible metal; it was used for the conductive layer of the needle array. To evaluate the performance of the fabricated electrodes, they were compared with the conventional surface electrodes in nerve conduction velocity experiment. The recorded signals showed a much lower contact resistance and higher bandwidth in low frequencies for the fabricated microneedle electrodes compared to those of the conventional electrodes. These results indicate the electrode-tissue interface capacitance and charge transfer resistance have been increased in our designed electrodes, while the contact resistance decreased. These changes will lead to less harmful Faradaic current passing through the tissue during stimulation in different frequencies. We also compared the designed microneedle electrodes with conventional ones by a 3-dimensional finite element simulation. The results demonstrated that the current density in the deep layers of the skin and the directivity toward a target nerve for microneedle electrodes were much more than those for the conventional ones. Therefore, the designed electrodes are much more efficient than the conventional electrodes for superficial transcutaneous nerve stimulation purposes.

SAR analysis of a needle type applicator made from a shape memory alloy using 3-D anatomical human head model

International Nuclear Information System (INIS)

Kubo, Mitsunori; Mimoto, Naoki; Hirashima, Taku; Morita, Emi; Shindo, Yasuhiro; Kato, Kazuo; Takahashi, Hideaki; Uzuka, Takeo; Fujii, Yukihiko

2009-01-01

This paper describes the possibility of a new heating method with a needle applicator made of a shape memory alloy (SMA) to expand the heating area for interstitial brain tumor hyperthermia treatments. The purpose of the study described here is to show the capability of the method to expand a defined heating region with the developed three-dimensional (3-D) anatomical human head model using the finite element method (FEM). One major disadvantage of radiofrequency (RF) interstitial hyperthermia treatment is that this heating method has a small heating area. To overcome this problem, a new type of needle made of a SMA was developed. The specific absorption rate (SAR) distributions of this proposed method, when applied to the 3-D anatomical human head model reconstructed from two-dimensional (2-D) MRI and X-ray CT images, were calculated with computer simulations. The calculated SAR distributions showed no unexpected hot spots within the model. The heated area was localized around the tumor. These results suggest that the proposed heating method using the SMA needle applicator and the developed method for reconstructing a 3-D anatomical human head model are capable of being used for invasive brain tumor hyperthermia treatments. (author)

Using insulin pen needles up to five times does not affect needle tip shape nor increase pain intensity.

Science.gov (United States)

Puder, Jardena J; Atar, Michael; Muller, Beat; Pavan, Marco; Keller, Ulrich

2005-02-01

Reusing insulin pen needles could help to reduce the increasing economic burden of diabetes. We tested the hypothesis that reusing insulin pen needles leads to needle tip deformity and increased pain. Three blinded reviewers assessed 123 electron microscope pictures analyzing needle tip deformity of insulin pen needles used up to four times by diabetic subjects and up to five times by blinded non-diabetic volunteers. The estimated frequency of needle use was correlated to the actual number of needle use. Pain intensity and unpleasantness of each injection were measured by a visual analogue scale and their differences analyzed by Kruskal-Wallis analysis of variance. Unused needles could be differentiated visually from used needles. However, there was no correlation between the actual and guessed number of times a needle was used (r = 0.07, P = 0.2). Evaluating all 270 injections, neither pain intensity nor unpleasantness increased with repeated injections of the same needles in people with diabetes (P = 0.1 and 0.96) and in the volunteers (P = 0.63 and 0.92). Using pen needles four to five times does not lead to progressive needle tip deformity and does not increase pain intensity or unpleasantness, but could increase convenience and lead to substantial financial savings in Europe of around EUR 100 million/year.

Brachytherapy needle deflection evaluation and correction

International Nuclear Information System (INIS)

Wan Gang; Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

2005-01-01

In prostate brachytherapy, an 18-gauge needle is used to implant radioactive seeds. This thin needle can be deflected from the preplanned trajectory in the prostate, potentially resulting in a suboptimum dose pattern and at times requiring repeated needle insertion to achieve optimal dosimetry. In this paper, we report on the evaluation of brachytherapy needle deflection and bending in test phantoms and two approaches to overcome the problem. First we tested the relationship between needle deflection and insertion depth as well as whether needle bending occurred. Targeting accuracy was tested by inserting a brachytherapy needle to target 16 points in chicken tissue phantoms. By implanting dummy seeds into chicken tissue phantoms under 3D ultrasound guidance, the overall accuracy of seed implantation was determined. We evaluated methods to overcome brachytherapy needle deflection with three different insertion methods: constant orientation, constant rotation, and orientation reversal at half of the insertion depth. Our results showed that needle deflection is linear with needle insertion depth, and that no noticeable bending occurs with needle insertion into the tissue and agar phantoms. A 3D principal component analysis was performed to obtain the population distribution of needle tip and seed position relative to the target positions. Our results showed that with the constant orientation insertion method, the mean needle targeting error was 2.8 mm and the mean seed implantation error was 2.9 mm. Using the constant rotation and orientation reversal at half insertion depth methods, the deflection error was reduced. The mean needle targeting errors were 0.8 and 1.2 mm for the constant rotation and orientation reversal methods, respectively, and the seed implantation errors were 0.9 and 1.5 mm for constant rotation insertion and orientation reversal methods, respectively

New radiofrequency device to reduce bleeding after core needle biopsy: Experimental study in a porcine liver model

International Nuclear Information System (INIS)

Lim, Sang Hyeok; Rhim, Hyun Chul; Lee, Min Woo; Song, Kyoung Doo; Kang, Tae Wook; Kim, Young Sun; Lim, Hyo Keun

2017-01-01

To evaluate the in vivo efficiency of the biopsy tract radiofrequency ablation for hemostasis after core biopsy of the liver in a porcine liver model, including situations with bleeding tendency and a larger (16-gauge) core needle. A preliminary study was performed using one pig to determine optimal ablation parameters. For the main experiment, four pigs were assigned to different groups according to heparinization use and biopsy needle caliber. In each pig, 14 control (without tract ablation) and 14 experimental (tract ablation) ultrasound-guided core biopsies were performed using either an 18- or 16-gauge needle. Post-biopsy bleeding amounts were measured by soaking up the blood for five minutes. The results were compared using the Mann-Whitney U test. The optimal parameters for biopsy tract ablation were determined as a 2-cm active tip electrode set at 40-watt with a tip temperature of 70–80℃. The bleeding amounts in all experimental groups were smaller than those in the controls; however they were significant in the non-heparinized pig biopsied with an 18-gauge needle and in two heparinized pigs (p < 0.001). In the heparinized pigs, the mean blood loss in the experimental group was 3.5% and 13.5% of the controls biopsied with an 18- and 16-gauge needle, respectively. Radiofrequency ablation of hepatic core biopsy tract ablation may reduce post-biopsy bleeding even under bleeding tendency and using a larger core needle, according to the result from in vivo porcine model experiments

New radiofrequency device to reduce bleeding after core needle biopsy: Experimental study in a porcine liver model

Energy Technology Data Exchange (ETDEWEB)

Lim, Sang Hyeok; Rhim, Hyun Chul; Lee, Min Woo; Song, Kyoung Doo; Kang, Tae Wook; Kim, Young Sun; Lim, Hyo Keun [Dept. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2017-01-15

To evaluate the in vivo efficiency of the biopsy tract radiofrequency ablation for hemostasis after core biopsy of the liver in a porcine liver model, including situations with bleeding tendency and a larger (16-gauge) core needle. A preliminary study was performed using one pig to determine optimal ablation parameters. For the main experiment, four pigs were assigned to different groups according to heparinization use and biopsy needle caliber. In each pig, 14 control (without tract ablation) and 14 experimental (tract ablation) ultrasound-guided core biopsies were performed using either an 18- or 16-gauge needle. Post-biopsy bleeding amounts were measured by soaking up the blood for five minutes. The results were compared using the Mann-Whitney U test. The optimal parameters for biopsy tract ablation were determined as a 2-cm active tip electrode set at 40-watt with a tip temperature of 70–80℃. The bleeding amounts in all experimental groups were smaller than those in the controls; however they were significant in the non-heparinized pig biopsied with an 18-gauge needle and in two heparinized pigs (p < 0.001). In the heparinized pigs, the mean blood loss in the experimental group was 3.5% and 13.5% of the controls biopsied with an 18- and 16-gauge needle, respectively. Radiofrequency ablation of hepatic core biopsy tract ablation may reduce post-biopsy bleeding even under bleeding tendency and using a larger core needle, according to the result from in vivo porcine model experiments.

Ultrasound-guided fine needle aspiration versus core needle biopsy: comparison of post-biopsy hematoma rates and risk factors.

Science.gov (United States)

Chae, In Hye; Kim, Eun-Kyung; Moon, Hee Jung; Yoon, Jung Hyun; Park, Vivian Y; Kwak, Jin Young

2017-07-01

To compare post-biopsy hematoma rates between ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy, and to investigate risk factors for post-biopsy hematoma. A total of 5304 thyroid nodules which underwent ultrasound guided biopsy were included in this retrospective study. We compared clinical and US features between patients with and without post-biopsy hematoma. Associations between these features and post-biopsy hematoma were analyzed. Post-biopsy hematoma rate was 0.8% (43/5121) for ultrasound guided-fine needle aspiration and 4.9% (9/183) for ultrasound guided-core needle biopsy (P core needle biopsy (9/179, 5.0%) than with ultrasound guided-fine needle aspiration (9/1138, 0.8%) (P core needle biopsy was the only significant risk factor for post-biopsy hematoma (adjusted Odds Ratio, 6.458, P core needle biopsy than in ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy was the only independent factor of post-biopsy hematoma in thyroid nodules.

Observation of electrostatically released DNA from gold electrodes with controlled threshold voltages.

Science.gov (United States)

Takeishi, Shunsaku; Rant, Ulrich; Fujiwara, Tsuyoshi; Buchholz, Karin; Usuki, Tatsuya; Arinaga, Kenji; Takemoto, Kazuya; Yamaguchi, Yoshitaka; Tornow, Marc; Fujita, Shozo; Abstreiter, Gerhard; Yokoyama, Naoki

2004-03-22

DNA oligo-nucleotides, localized at Au metal electrodes in aqueous solution, are found to be released when applying a negative bias voltage to the electrode. The release was confirmed by monitoring the intensity of the fluorescence of cyanine dyes (Cy3) linked to the 5' end of the DNA. The threshold voltage of the release changes depending on the kind of linker added to the DNA 3'-terminal. The amount of released DNA depends on the duration of the voltage pulse. Using this technique, we can retain DNA at Au electrodes or Au needles, and release the desired amount of DNA at a precise location in a target. The results suggest that DNA injection into living cells is possible with this method. (c) 2004 American Institute of Physics

Effects of electrode geometry on transient plasma induced ignition

International Nuclear Information System (INIS)

Shukla, B; Gururajan, V; Eisazadeh-Far, K; Windom, B; Egolfopoulos, F N; Singleton, D; Gundersen, M A

2013-01-01

Achieving effective ignition of reacting mixtures using nanosecond pulsed discharge non-equilibrium transient plasma (TP), requires that the effects of several experimental parameters be quantified and understood. Among them are the electrode geometry, the discharge location especially in non-premixed systems, and the relative ignition performance by spark and TP under the same experimental conditions. In the present investigation, such issues were addressed experimentally using a cylindrical constant volume combustion chamber and a counterflow flame configuration coupled with optical shadowgraph that enables observation of how and where the ignition process starts. Results were obtained under atmospheric pressure and showed that the electrode geometry has a notable influence on ignition, with the needle-to-semicircle exhibiting the best ignition performance. Furthermore, it was determined that under non-premixed conditions discharging TP in the reactants mixing layer was most effective in achieving ignition. It was also determined that in the cases considered, the TP induced ignition initiates from the needle head where the electric field and electron densities are the highest. In the case of a spark, however, ignition was found to initiate always from the hot region between the two electrodes. Comparison of spark and TP discharges in only air (i.e. without fuel) and ignition phenomena induced by them also suggest that in the case of TP ignition is at least partly non-thermal and instead driven by the production of active species. Finally, it was determined that single pulsed TP discharges are sufficient to ignite both premixed and non-premixed flames of a variety of fuels ranging from hydrogen to heavy fuels including F-76 diesel and IFO380 bunker fuel even at room temperature. (paper)

21 CFR 880.5580 - Acupuncture needle.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Acupuncture needle. 880.5580 Section 880.5580 Food... § 880.5580 Acupuncture needle. (a) Identification. An acupuncture needle is a device intended to pierce the skin in the practice of acupuncture. The device consists of a solid, stainless steel needle. The...

Effect and safety of deep needling and shallow needling for functional constipation: a multicenter, randomized controlled trial.

Science.gov (United States)

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

2014-12-01

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 constipation were randomized to the deep needling group (237), shallow needling group (119), and lactulose-controlled group (119) in a ratio of 2:1:1. Sessions lasted 30 minutes each time and took place 5 times a week for 4 weeks in 2 acupuncture groups. Participants in the lactulose group took lactulose orally for 16 continuous weeks. The primary outcome was the change from baseline of mean weekly spontaneous bowel movements (SBMs) during week 1 to 4 (changes from the baselines of the weekly SBMs at week 8 and week 16 in follow-up period were also assessed simultaneously). Secondary outcomes were the weekly SBMs of each assessing week, the mean score change from the baseline of constipation-related symptoms over week 1 to 4, and the time to the first SBM. Emergency drug usage and adverse effects were monitored throughout the study.SBMs and constipation-related symptoms were all improved in the 3 groups compared with baseline at each time frame (Pdeep needling group, 2 (1.75) in the shallow needling group, and 2 (2) in the lactulose group (P>0.05, both compared with the lactulose group). The changes of mean weekly SBMs at week 8 and week 16 in the follow-up period were 2 (2), 2 (2.5) in the deep needling group, 2 (3), 1.5 (2.5) in the shallow needling group, and 1 (2), 1 (2) in the lactulose group (Pdeep or shallow needling group. Deep and shallow needling at Tianshu (ST25) can improve intestinal function remarkably and safely. Therapeutic effects of deep and shallow needling are not

[Stiletto needle and needle-knife for influence of gravity index in treating knee osteoarthritis].

Science.gov (United States)

Gu, Li-Jun; Zhang, Bin; Li, Wen-Hua; Tang, Yan; Dong, Fu-Hui

2017-12-25

To explore stiletto needle and needle-knife for influence of double sufficient weight in treating knee osteoarthritis patients. One hundred and thirteen early and medium term knee osteoarthritis patients were randomly divided into three groups, including stiletto needle group(38 cases), needle-knife group (38 cases) and voltaren group (37 cases). In stiletto needle group, there were 13 males and 25 females with an average of(55.87±7.72) years old, treated by stiletto needle once a week, and 2 weeks were a course; there were 11 males and 27 females in needle-knife group with an average of(57.11±7.07) years old, treated by acupotome once a week, and 2 weeks were a course; there were 12 males and 25 females in voltaren group with an average age of(57.62±8.08) years old, treated by votalin emulsion smearing 3 to 5 cm on painful area of knee joint, three times a day for 2 weeks; 36 patients in normal group, including 11 males and 25 females with a mean age of (55.28±7.55) years old, treated with nothing. Gravitational four lattice used to measure bipedal back and forth load before and after treatment in further observe weight-bearing situation among three groups, d value, which was the distance from center of gravity to original point, was measured as a obvervational index, JOA score was used to evaluate clinical effect. Five patients were fall out, including 2 patients in stiletto needle group, 2 patients in needle-knife group and 1 patient in voltaren group. Other 108 patients were followed-up from 28 to 35 d with an average of 30 d, and without untoward effect. There was significant difference in d value between treatment group and control group at 1 month after treatment( P 0.05), and d value was decreased before treatment than that of after treatment. There was no significant difference in JOA score among treatment group after treatment at 1 month( P 0.05) after treatment at 1 month. Stiletto needle, needle-knife and voltaren for the treatment of knee

[Effects of slow twisting needle insertion and tubing needle insertion at Neiguan (PC 6) on cardiovascular function: a comparative study].

Science.gov (United States)

Ning, Shaoli; Zhao, Lihua; Xu, Lingjun; Huang, Yu; Pang, Yong; Huang, Dingjian

2016-01-01

To compare the effects between slow twisting needle insertion and tubing needle insertion. With cross-over design, 100 healthy young subjects (half male and half female) aged from 19 to 23 years were randomly divided into two groups by random digital table, 50 cases in each one. At the first stage, subjects in the group A were treated with slow twisting needle insertion while, subjects in,the group B were treated with tubing needle insertion. One week later, the procedure of second stage was performed alternately. The needle was inserted into Neiguan (PC 6) with two methods by one acupuncturist. The needle was retained for 5 min before removal. Five min before needle insertion as well as needle withdrawal and 30 min after needle withdrawal, ZXG-E automatic cardiovascular diagnostic apparatus was used to test cardiovascular function. At the tim of needle withdrawal, slow twisting needle insertion could improve effect work of kinetics (EWK), effective blood volume (BV) and reduce elastic expansion coefficient of blood vessel (FEK) and left ventricular spray blood impedance (VER), which was significantly different from tubing needle insertion (all P 0.05). The slow twisting needle insertion is significantly superior to tubing needle insertion on lowering vascular tension and VER, improving EWK and BV.

[Design and application of silver needle-knife].

Science.gov (United States)

Sun, Guodong; Shi, Bin; Zhang, Benwu; Xu, Haidong

2015-04-01

A silver needle-knife which has the dual function of silver needle and needle-knife is designed. The main components of this silver needle-knife are approximately 50% silver and approximately 50% nichrome. The silver needle-knife is composed of five parts, including needle-knife tail, spiral handle; steering handle, needle-knife body and needle-knife edge. It converges the advantages of needle-knife and silver needle, which can cut loose of diseased tissue and peel adhesion of lesions, but also be heated with moxa cone and thermal therapeutic instrument, and connect with electroacupuncture apparatus. It has the function of warming channel and removing coldness, dispelling wind and eliminating dampness, resolving spasm and relieving pain, dredging the channel and so on. Due to the spiral handle and the steering handle, the operation is easier, which reduces the blindness of cutting and increase the safety. It is mainly used for soft tissue injury, rheumatism and rheumatoid arthritis, as well as degenerative diseases of spine and joint, and it has obvious efficacy on some internal medical diseases.

CT-guided transthoracic cutting needle biopsy of intrathoracic lesions: Comparison between coaxial and single needle technique

International Nuclear Information System (INIS)

Wu, Reng-Hong; Tzeng, Wen-Sheng; Lee, Wei-Jing; Chang, Shih-Chin; Chen, Chia-Huei; Fung, Jui-Lung; Wang, Yen-Jen; Mak, Chee-Wai

2012-01-01

Purpose: To evaluate the complication rates and diagnostic accuracy of two different CT-guided transthoracic cutting needle biopsy techniques: coaxial method and single needle method. Methods: This study involved 198 consecutive subjects with 198 intrathoracic lesions. The first 98 consecutive subjects received a single needle cutting technique and the next 100 consecutive subjects received a coaxial technique. Both groups were compared in relation the diagnostic accuracy and complication rates. Results: No significant difference was found between the two groups concerning patient characteristics, lesions and procedure variables. There was a borderline statistical difference in the incidence of pneumothorax at within 24-h post biopsy between patients in the single needle group (5%) and the coaxial group (13%) (P = 0.053). Little difference was found in the pneumothorax rate at immediately post biopsy between the two groups, which was 28% in the single needle group and 31% in the coaxial group. There was no significant difference in the hemoptysis rate between the two groups, which was 9.2% in the single needle group and 11% in the coaxial group. Both techniques yielded an overall diagnostic accuracy of 98% for malignant lesions with similar sensitivity (single needle: 96.9% vs. coaxial: 96.4%) and specificity (single needle: 100% vs. coaxial: 100%). Conclusion: There is little difference in the pneumothorax rates and bleeding complications between patients who either received a single needle or a coaxial transthoracic cutting biopsy. Both techniques produce an overall diagnostic accuracy of 98% for malignant lesions.

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

International Nuclear Information System (INIS)

Kuang Yuanwen; Wen Dazhi; Zhou Guoyi; Liu Shizhong

2007-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Kuang Yuanwen [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: kuangyw@scbg.ac.cn; Wen Dazhi [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: dzwen@scbg.ac.cn; Zhou Guoyi [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: gyzhou@scbg.ac.cn; Liu Shizhong [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: lsz@scbg.ac.cn

2007-01-15

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.

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

Energy Technology Data Exchange (ETDEWEB)

Kuang Yuanwen [South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: kuangyw@scbg.ac.cn; Wen Dazhi [South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: dzwen@scbg.ac.cn; Zhou Guoyi [South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: gyzhou@scbg.ac.cn; Liu Shizhong [South China Botanical Garden, Chinese Academy of Sciences, 510650 Guangzhou (China)]. E-mail: lsz@scbg.ac.cn

2007-02-15

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 and 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.

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

International Nuclear Information System (INIS)

Kuang Yuanwen; Wen Dazhi; Zhou Guoyi; Liu Shizhong

2007-01-01

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 and 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

Comparison of specimen adequacy in fine needle aspiration cytology performed with different gauge needles in palpable external swellings

International Nuclear Information System (INIS)

Sarfraz, T.; Bashir, S.; Tariq, H.; Malik, T.M.

2013-01-01

Background: Fine Needle Aspiration Cytology (FNAC) of external swellings may yield different specimen adequacy depending on different gauge needles used for aspiration. Objective: To compare the specimen adequacy aspirated by various gauge (21 and 22) needles in external palpable swellings of lymph nodes, thyroid gland, salivary glands, breast and soft tissue. Study Design: Comparative cross sectional study. Duration: Six months (1st Jan 2012 to 30th June 2012). Setting: Histopathology/Cytology department Combined Military Hospital Peshawar (Pakistan). Methodology: This was a prospective study of 200 cases in which FNAC was performed with either 21 or 22 gauge needles (100 cases with 21 gauge and 100 with 22 gauge needles). Equal number of aspirations were done with 21 and 22 gauge needles from the swellings of thyroid gland, lymph nodes, salivary glands, breast and soft tissue. Results were analyzed for specimen adequacy by using SPSS 17. Results: A total number of 200 cases were recruited in this study, out of which 100 were aspirated with 21 gauge needles and 100 with 22 gauge needles. Specimen adequacy in swellings of thyroid, lymph nodes and salivary glands was better with 22 gauge amounting 90%, 80% and 80% respectively, as compared to yield with 21 gauge needles which was 85%, 70% and 60% respectively. On the other hand in swellings of breast and soft tissue, the specimen adequacy was better with 21 gauge needles giving 98% and 90 % adequate yield respectively as compared to 22 gauge needles which was 70% and 40 % respectively. Conclusion: Needles of smaller gauge (22 gauge) give a better yield in swellings of thyroid, lymph nodes and salivary gland while in swellings of breast and soft tissue sample adequacy is better with larger gauge needle (21 gauge). (author)

Electrochemical Synthesis of Graphene/MnO2 Nano-Composite for Application to Supercapacitor Electrode.

Science.gov (United States)

Jeong, Kwang Ho; Lee, Hyeon Jeong; Simpson, Michael F; Jeong, Mun

2016-05-01

Graphene/MnO2 nano-composite was electrochemically synthesized for application to an electrode material for electrochemical supercapacitors. The nanosized needle-like MnO2 was obtained by use of a graphene substrate. The prepared composite exhibited an ideal supercapacitive behavior. A capacitance retention of 94% was achieved with a 4 h deposition time (an initial capacitance of 574 mF/cm2 at a scan rate of 20 mV/s) and the retention declined with further deposition time. The results demonstrate enhanced contact between the electrode and electrolyte and improved power density as an electrochemical capacitor.

A support system in virtual reality for effective hyperthermia treatments. Heating properties of needle applicator for brain tumors

International Nuclear Information System (INIS)

Shindo, Yasuhiro; Iseki, Yuya; Nakane, Kazuya; Mimoto, Naoki; Kubo, Mitsunori; Kato, Kazuo; Takahashi, Hideaki; Uzuka, Takeo; Fujii, Yukihiko

2011-01-01

This paper describes the effectiveness of the developed simulator system for performing an effective hyperthermia treatment with a needle applicator in virtual reality (VR). The human brain is protected by the skull, which makes it difficult to non-invasively heat deep brain tumors with electromagnetic energy. Generally, needle applicators were used in clinical practice to heat brain tumors. However, some problems exist. One is that this heating method has a small heating area around the needle. In order to expand the heating area of a needle applicator, we developed a new type of needle applicator made from a shape memory alloy (SMA). The thermal properties of the SMA were checked experimentally using the developed heating system. As a result, the proposed needle applicator made of SMA is useful to create a wider heating area inside a tumor. Another problem is that medical doctors find it difficult to put a needle applicator into a target point inside of tumors. Therefore, a support system for performing an effective hyperthermia treatment is required in the clinic. In this paper, first, we constructed an anatomical 3-D model from magnetic resonance imaging (MRI) and X-ray computed tomography (CT) images by using 3-D computer aided design (CAD) software. Second, we presented the finite element method (FEM) model which is divided into non-linear elements on 3-D computer graphics (CG). Finally, we calculated temperature distributions using the 3-D FEM model with blood perfusion during hyperthermia treatments. From these results, it was found that the proposed VR system is effective for performing hyperthermia treatments. (author)

Arterial puncture using insulin needle is less painful than with standard needle: a randomized crossover study.

Science.gov (United States)

Ibrahim, Irwani; Yau, Ying Wei; Ong, Lizhen; Chan, Yiong Huak; Kuan, Win Sen

2015-03-01

Arterial punctures are important procedures performed by emergency physicians in the assessment of ill patients. However, arterial punctures are painful and can create anxiety and needle phobia in patients. The pain score of radial arterial punctures were compared between the insulin needle and the standard 23-gauge hypodermic needle. In a randomized controlled crossover design, healthy volunteers were recruited to undergo bilateral radial arterial punctures. They were assigned to receive either the insulin or the standard needle as the first puncture, using blocked randomization. The primary outcome was the pain score measured on a 100-mm visual analogue scale (VAS) for pain, and secondary outcomes were rate of hemolysis, mean potassium values, and procedural complications immediately and 24 hours postprocedure. Fifty healthy volunteers were included in the study. The mean (±standard deviation) VAS score in punctures with the insulin needle was lower than the standard needle (23 ± 22 mm vs. 39 ± 24 mm; mean difference = -15 mm; 95% confidence interval = -22 mm to -7 mm; p standard needle (31.3% vs. 11.6%, p = 0.035; and 4.6 ±0.7 mmol/L vs. 4.2 ±0.5 mmol/L, p = 0.002). Procedural complications were lower in punctures with the insulin needle both immediately postprocedure (0% vs. 24%; p standard needles. However, due to the higher rate of hemolysis, its use should be limited to conditions that do not require a concurrent potassium value in the same blood sample. © 2015 by the Society for Academic Emergency Medicine.

Interplay of tumor vascular oxygenation and tumor pO2 observed using near-infrared spectroscopy, an oxygen needle electrode, and 19F MR pO2 mapping.

Science.gov (United States)

Kim, Jae G; Zhao, Dawen; Song, Yulin; Constantinescu, Anca; Mason, Ralph P; Liu, Hanli

2003-01-01

This study investigates the correlation of tumor blood oxygenation and tumor pO(2) with respect to carbogen inhalation. After having refined and validated the algorithms for calculating hemoglobin concentrations, we used near-infrared spectroscopy (NIRS) to measure changes of oxygenated hemoglobin concentration (delta[HbO(2)]) and used an oxygen needle electrode and (19)F MRI for pO(2) measurements in tumors. The measurements were taken from Dunning prostate R3327 tumors implanted in rats, while the anesthetized rats breathed air or carbogen. The NIRS results from tumor measurements showed significant changes in tumor vascular oxygenation in response to carbogen inhalation, while the pO(2) electrode results showed an apparent heterogeneity for tumor pO(2) response to carbogen inhalation, which was also confirmed by (19)F MR pO(2) mapping. Furthermore, we developed algorithms to estimate hemoglobin oxygen saturation, sO(2), during gas intervention based on the measured values of delta[HbO(2)] and pO(2). The algorithms have been validated through a tissue-simulating phantom and used to estimate the values of sO(2) in the animal tumor measurement based on the NIRS and global mean pO(2) values. This study demonstrates that the NIRS technology can provide an efficient, real-time, noninvasive approach to monitoring tumor physiology and is complementary to other techniques, while it also demonstrates the need for an NIR imaging technique to study spatial heterogeneity of tumor vasculature under therapeutic interventions. Copyright 2003 Society of Photo-Optical Instrumentation Engineers

[Needling technique of Professor Li Yan-Fang].

Science.gov (United States)

Li, Li-Jun

2014-01-01

Experiences of needling techniques of Professor LI Ya- fang is introduced in this article. Gentle and superficial insertion is adopted by Professor LI in clinic. Emphases are put on the qi regulation function, needling sensation to the affected region and insertion with both hands, especially the function of the left hand as pressing hand. The gentle and superficial insertion should be done as the follows: hold the needle with the right hand, press gently along the running course of meridians with the left hand to promote qi circulation, hard pressing should be applied at acupoints to disperse the local qi and blood, insert the needle gently and quickly into the subcutaneous region with the right hand, and stop the insertion when patient has the needling sensation. While the fast needling is characterized with shallow insertion and swift manipulation: the left hand of the manipulator should press first along the running course of the meridian, and fix the local skin, hold the needle with the right hand and insert the needle quickly into the acupoint. Withdrawal of the needle should be done immediately after the reinforcing and reducing manipulations. Professor LI is accomplished in qi regulation. It is held by him that regulating qi circulation is essence of acupuncture, letting the patient get the needling sensation is the most important task of needling. Lifting, thrusting and rotation manipulations should be applied to do reinforcing or reducing. The tissue around the tip of the needle should not be too contracted or too relaxed, and the resistance should not be too strong or too weak. The feeling of the insertion hand of the practitioner should not be too smooth or too hesitant. Needle should be inserted into the skin quickly at the moment of hard pressing by the left hand. And then, slow rotation and gentle lifting and thrusting can be applied to promote the needling sensation like electric current pass through and to reach the affected region along the

A novel prototype 3/5 laparoscopic needle driver: A validation study with conventional laparoscopic needle driver.

Science.gov (United States)

Ganpule, Arvind P; Deshmukh, Chaitanya S; Joshi, Tanmay

2018-01-01

The challenges in laparoscopic suturing include need to expertise to suture. Laparoscopic needle holder is a" key" instrument to accomplish this arduous task. The objective of this new invention was to develop a laparoscopic needle holder which would be adapted to avoid any wobble (with a shaft diameter same as a 5mm port), ensure accurate and dexterous suturing not just in adult patients but pediatric patients alike (with a short shaft diameter) and finally ensure seamless throw of knots with a narrow tip configuration. We did an initial evaluation to evaluate the validity of the prototype needle holder and its impact on laparoscopic suturing skills by experienced laparoscopic surgeons and novice laparoscopic Surgeons. Both the groups of surgeons performed two tasks. The first task was to grasp the needle and position it in an angle deemed ideal for suturing. The second task was to pass suture through two fixed points and make a single square knot. At the end of the tasks each participant was asked to complete a 5- point Likert's scale questionnaire (8 items; 4 items of handling and 4 items of suturing) rating each needle holder. In expert group, the mean time to complete task 1 was shorter with prototype 3/5 laparoscopic needle holder (11.8 sec Vs 20.8 sec). The mean time to complete task 2 was also shorter with prototype 3/5 laparoscopic needle holder (103.2 sec Vs 153.2 sec). In novice group, mean time to complete both the task was shorter with prototype 3/5 laparoscopic needle holder. The expert laparoscopic surgeons as well as novice laparoscopic surgeons performed laparoscopic suturing faster and with more ease while using the prototype 3/5 laparoscopic needle holder.

Comparative cyto-histological study of needle tip aspirates and entry sites after intravitreal injection using different needle types.

Directory of Open Access Journals (Sweden)

Lyubomyr Lytvynchuk

Full Text Available A comparison of the cellular content of needle tip aspirates and entry sites after transconjunctival intravitreal injection (IVI using different needle types was performed. White outbred rats and human cadaver eyes were used for IVI by hypodermic 27 gauge (G and 30G needles, and spinal anesthesia Pencan 27G needles. Aspiration of vitreous for quantitative morphological and cell cultivation analysis, as well as cyto-histological analysis of aspirates and entry sites were carried out. The most common cells in the aspirates from all needle types were conjunctival epithelial-, ciliary body non-pigmented epithelial- and sclerocyte-like cells and granular proteins. Crystallized vitreous specimens were present in each aspirate. The entry sites of hypodermic needles showed marked trauma in all wall layers of rat and human eyes accompanied by cellular destruction and hemorrhages. Pencan 27G needle caused less tissue trauma with partial reposition of sclerocytes. Transconjunctival IVIs with hypodermic 27G and 30G, and Pencan 27G needles result in trauma of all layers of the eyeball. The possible consequences of cellular content being cut and injected into the eye, as well as the entry site wound shape deserve future consideration and improvements.

Physical Properties Of Acupuncture Needles: Do Disposable Acupuncture Needles Break With Normal Use

Science.gov (United States)

2016-06-01

Orofacial Pain Graduate...JOURNAL PHYSICAL PROPERTIES OF ACUPUNCTURE NEEDLES: DO DISPOSABLE ACUPUNCTURE NEEDLES BREAK WITH NORMAL USE? James Kyle Vick DDS, Orofacial Pain ...MS CAPT, DC, USN Orofacial Pain Department Head Naval Postgraduate Dental School vi    TABLE OF CONTENTS GUIDELINE I. TITLE

Characterization of porous texture of cermet electrode for steam electrolysis at intermediate temperature

International Nuclear Information System (INIS)

Deslouis, C.; Keddam, M.; Rahmouni, K.; Takenouti, H.; Grasset, F.; Lacroix, O.; Sala, B.

2011-01-01

Electrodes designed for PCEC (Proton Conducting Electrolyzing Cell) should ensure both electron and proton conductions and also allowed the supply or the draining of gaseous phase such as steam, hydrogen and oxygen. Porous cermet electrodes fulfil these requirements: percolated metallic phase for electron conduction, ceramic for proton conduction, and pores for transport of reactant and products in gas phase. The electrochemical reactions will take place at boundaries of these three phases, commonly named triple points. Therefore, the cermet electrode has to possess a sufficient open porosity and the expanded metallic surface area exposed to pores as large as possible. In this work, the pore texture of cermet electrodes was characterized by means of Electrochemical Impedance Spectroscopy in aprotic liquid medium. The parameter regression calculation based on de Levie's transmission-line model allowed us to determine the pore texture characterized by expanded surface area, number, mean radius of pores, and open porosity.

Changing the needle for lumbar punctures

DEFF Research Database (Denmark)

Engedal, Thorbjørn Søndergaard; Ording, H.; Vilholm, O. J.

2015-01-01

Objective: Post-dural puncture headache (PDPH) is a common complication of diagnostic lumbar punctures. Both a non-cutting needle design and the use of smaller size needles have been shown to greatly reduce the risk of PDPH. Nevertheless, larger cutting needles are still widely used. This study d...

Variations in dark respiration and mitochondrial numbers within needles of Pinus radiata grown in ambient or elevated CO2 partial pressure

International Nuclear Information System (INIS)

Griffin, K. L.; Anderson, O. R.; Tissue, D. T.; Turnbull, M. H.; Whitehead, D.

2004-01-01

An experiment involving comparison of within-leaf variations in cell size, mitochondrial numbers and dark respiration in the most recently expanded tip, the mid-section and the base of needles of Pinus radiata grown for four years at ambient and elevated carbon dioxide partial pressure, is described. Results showed variation in mitochondrial numbers and respiration along the length of the needle, with the highest number of mitochondria per unit cytoplasm and the highest rate of respiration per unit leaf area at the base of the needle. Elevated carbon dioxide pressure caused the number of mitochondria per unit cytoplasm to double regardless of location (tip, basal or mid sections). Under these conditions, greatest mitochondrial density was observed at the tip. The mean size of mitochondria was not affected by either growth at elevated carbon dioxide pressure or by position on the needle. Respiration per unit leaf area at elevated carbon dioxide pressure was highest at the tip of needles, decreasing towards the middle and basal sections. The observed data supports the hypothesis that the highest number of mitochondria per unit area of cytoplasm occurs at the base of the needle, but does not support the hypothesis that the lowest rate of respiration also occurs at the base. It is suggested that the relationship that determines the association between structure and function in these needles is more complex than previously thought. 33 refs., 4 tabs., 1 fig

Irreversible Electroporation of the Pancreas Using Parallel Plate Electrodes in a Porcine Model: A Feasibility Study.

Science.gov (United States)

Rombouts, Steffi J E; Nijkamp, Maarten W; van Dijck, Willemijn P M; Brosens, Lodewijk A A; Konings, Maurits; van Hillegersberg, R; Borel Rinkes, Inne H M; Hagendoorn, Jeroen; Wittkampf, Fred H; Molenaar, I Quintus

2017-01-01

Irreversible electroporation (IRE) with needle electrodes is being explored as treatment option in locally advanced pancreatic cancer. Several studies have shown promising results with IRE needles, positioned around the tumor to achieve tumor ablation. Disadvantages are the technical difficulties for needle placement, the time needed to achieve tumor ablation, the risk of needle track seeding and most important the possible occurrence of postoperative pancreatic fistula via the needle tracks. The aim of this experimental study was to evaluate the feasibility of a new IRE-technique using two parallel plate electrodes, in a porcine model. Twelve healthy pigs underwent laparotomy. The pancreas was mobilized to enable positioning of the paddles. A standard monophasic external cardiac defibrillator was used to perform an ablation in 3 separate parts of the pancreas; either a single application of 50 or 100J or a serial application of 4x50J. After 6 hours, pancreatectomy was performed for histology and pigs were terminated. Histology showed necrosis of pancreatic parenchyma with neutrophil influx in 5/12, 11/12 and 12/12 of the ablated areas at 50, 100, and 4x50J respectively. The electric current density threshold to achieve necrosis was 4.3, 5.1 and 3.4 A/cm2 respectively. The ablation threshold was significantly lower for the serial compared to the single applications (p = 0.003). The content of the ablated areas differed between the applications: areas treated with a single application of 50 J often contained vital areas without obvious necrosis, whereas half of the sections treated with 100 J showed small islands of normal looking cells surrounded by necrosis, while all sections receiving 4x 50 J showed a homogeneous necrotic lesion. Pancreatic tissue can be successfully ablated using two parallel paddles around the tissue. A serial application of 4x50J was most effective in creating a homogeneous necrotic lesion.

Irreversible Electroporation of the Pancreas Using Parallel Plate Electrodes in a Porcine Model: A Feasibility Study.

Directory of Open Access Journals (Sweden)

Steffi J E Rombouts

Full Text Available Irreversible electroporation (IRE with needle electrodes is being explored as treatment option in locally advanced pancreatic cancer. Several studies have shown promising results with IRE needles, positioned around the tumor to achieve tumor ablation. Disadvantages are the technical difficulties for needle placement, the time needed to achieve tumor ablation, the risk of needle track seeding and most important the possible occurrence of postoperative pancreatic fistula via the needle tracks. The aim of this experimental study was to evaluate the feasibility of a new IRE-technique using two parallel plate electrodes, in a porcine model.Twelve healthy pigs underwent laparotomy. The pancreas was mobilized to enable positioning of the paddles. A standard monophasic external cardiac defibrillator was used to perform an ablation in 3 separate parts of the pancreas; either a single application of 50 or 100J or a serial application of 4x50J. After 6 hours, pancreatectomy was performed for histology and pigs were terminated.Histology showed necrosis of pancreatic parenchyma with neutrophil influx in 5/12, 11/12 and 12/12 of the ablated areas at 50, 100, and 4x50J respectively. The electric current density threshold to achieve necrosis was 4.3, 5.1 and 3.4 A/cm2 respectively. The ablation threshold was significantly lower for the serial compared to the single applications (p = 0.003. The content of the ablated areas differed between the applications: areas treated with a single application of 50 J often contained vital areas without obvious necrosis, whereas half of the sections treated with 100 J showed small islands of normal looking cells surrounded by necrosis, while all sections receiving 4x 50 J showed a homogeneous necrotic lesion.Pancreatic tissue can be successfully ablated using two parallel paddles around the tissue. A serial application of 4x50J was most effective in creating a homogeneous necrotic lesion.

Analysis of the NovoTwist pen needle in comparison with conventional screw-thread needles.

Science.gov (United States)

Aye, Tandy

2011-11-01

Administration of insulin via a pen device may be advantageous over a vial and syringe system. Hofman and colleagues introduce a new insulin pen needle, the NovoTwist, to simplify injections to a small group of children and adolescents. Their overall preferences and evaluation of the handling of the needle are reported in the study. This new needle has the potential to ease administration of insulin via a pen device that may increase both the use of a pen device and adherence to insulin therapy. © 2011 Diabetes Technology Society.

Intra-operative navigation of a 3-dimensional needle localization system for precision of irreversible electroporation needles in locally advanced pancreatic cancer.

Science.gov (United States)

Bond, L; Schulz, B; VanMeter, T; Martin, R C G

2017-02-01

Irreversible electroporation (IRE) uses multiple needles and a series of electrical pulses to create pores in cell membranes and cause cell apoptosis. One of the demands of IRE is the precise needle spacing required. Two-dimensional intraoperative ultrasound (2-D iUS) is currently used to measure inter-needle distances but requires significant expertise. This study evaluates the potential of three-dimensional (3-D) image guidance for placing IRE needles and calculating needle spacing. A prospective clinical evaluation of a 3-D needle localization system (Explorer™) was evaluated in consecutive patients from April 2012 through June 2013 for unresectable pancreatic adenocarcinoma. 3-D reconstructions of patients' anatomy were generated from preoperative CT images, which were aligned to the intraoperative space. Thirty consecutive patients with locally advanced pancreatic cancer were treated with IRE. The needle localization system setup added an average of 6.5 min to each procedure. The 3-D needle localization system increased surgeon confidence and ultimately reduced needle placement time. IRE treatment efficacy is highly dependent on accurate needle spacing. The needle localization system evaluated in this study aims to mitigate these issues by providing the surgeon with additional visualization and data in 3-D. The Explorer™ system provides valuable guidance information and inter-needle distance calculations. Copyright © 2016 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Effect of Blinding With a New Pragmatic Placebo Needle

Science.gov (United States)

Liu, Baoyan; Xu, Huanfang; Ma, Rui; Mo, Qian; Yan, Shiyan; Liu, Zhishun

2014-01-01

Abstract Placebo control is a useful method for determining the efficacy of a therapy. In acupuncture researches, the preferred method for placebo control is acupuncture using a placebo needle that has a blunt tip and achieves no skin penetration. We performed a crossover study to validate the blinding effect of a new type of placebo needle. Sixty volunteers were randomized to receive acupuncture using 2 types of needles with different sequences: sequence AB, involving first the pragmatic placebo needle and then the real needle, and sequence BA, in a reverse order. Placebo acupuncture was performed by administering the placebo needle through an adhesive pad without skin penetration on the acupoints LI4, RN12, BL25, and BL36. Real acupuncture was performed by needling through the pad and penetrating the skin to 15 mm using a real needle on the same acupoints. The acupuncture was administered every other day with 3 sessions for 1 type of needle. The primary outcome was the perception of needle penetration. Besides degree of acupuncture pain, type, and degree of needle sensation, needle acceptability and factors influencing the subject blinding effect were assessed. Needle penetration was felt by 100%, 90% (54/60), 88.3% (53/60), and 95% (57/60) of volunteers receiving placebo acupuncture and 98.3% (59/60), 96.7% (58/60), 95% (57/60), and 95% (57/60) of volunteers receiving real acupuncture on LI4, RN12, BL25, and BL36, respectively. Differences of the volunteers’ perception of needle penetration between the placebo needle and real needle were not significant for the 4 acupoints (all P > 0.05). Volunteers experienced fewer distension sensations (P = 0.01), a lower degree of needle sensation (P = 0.007), and less pain (P = 0.006) during placebo acupuncture than during real acupuncture. The placebo needle was more easily accepted than the real needle (OR = 1.63, 95% CI, 1.01–2.64). The influences of age, sex, educational level, acupuncture

Design and Production of an Articulating Needle Guide for Ultrasound-Guided Needle Block Manufactured With a Three-Dimensional Printer: Technical Communication.

Science.gov (United States)

Bigeleisen, Paul E

2017-05-15

Needle guides may allow the practitioner to align the needle with the probe when ultrasound-guided nerve block is performed. The author's goal was to design and fabricate an inexpensive ($1.90), disposable, needle guide that could articulate over a range from 85 degrees to 0 degrees with a three-dimension printer. Three-dimensional representations of an L50, L25, and C 60 ultrasound probe (Sono Site, Bothell, WA) were created using a laser scanner. Computer-aided design software (Solid Works, Waltham, MA) was used to design a needle bracket and needle guide to attach to these probes. A three-dimensional printer was used to fabricate the needle bracket and guide with acrylonitrile polybutadiene polystyrene. An echogenic needle was held in plane with the needle guide. The author performed a supraclavicular block in a morbidly obese patient. The needle was easily visualized. Similar guides that are commercially available cost as much as $400. A knowledge of computer-aided design is necessary for this work.

Laser Generated Leaky Acoustic Waves for Needle Visualization.

Science.gov (United States)

Wu, Kai-Wen; Wang, Yi-An; Li, Pai-Chi

2018-04-01

Ultrasound (US)-guided needle operation is usually used to visualize both tissue and needle position such as tissue biopsy and localized drug delivery. However, the transducer-needle orientation is limited due to reflection of the acoustic waves. We proposed a leaky acoustic wave method to visualize the needle position and orientation. Laser pulses are emitted on top of the needle to generate acoustic waves; then, these acoustic waves propagate along the needle surface. Leaky wave signals are detected by the US array transducer. The needle position can be calculated by phase velocities of two different wave modes and their corresponding emission angles. In our experiments, a series of needles was inserted into a tissue mimicking phantom and porcine tissue to evaluate the accuracy of the proposed method. The results show that the detection depth is up to 51 mm and the insertion angle is up to 40° with needles of different diameters. It is demonstrated that the proposed approach outperforms the conventional B-mode US-guided needle operation in terms of the detection range while achieving similar accuracy. The proposed method reveals the potentials for further clinical applications.

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.

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

Ultrasound probe and needle-guide calibration for robotic ultrasound scanning and needle targeting.

Science.gov (United States)

Kim, Chunwoo; Chang, Doyoung; Petrisor, Doru; Chirikjian, Gregory; Han, Misop; Stoianovici, Dan

2013-06-01

Image-to-robot registration is a typical step for robotic image-guided interventions. If the imaging device uses a portable imaging probe that is held by a robot, this registration is constant and has been commonly named probe calibration. The same applies to probes tracked by a position measurement device. We report a calibration method for 2-D ultrasound probes using robotic manipulation and a planar calibration rig. Moreover, a needle guide that is attached to the probe is also calibrated for ultrasound-guided needle targeting. The method is applied to a transrectal ultrasound (TRUS) probe for robot-assisted prostate biopsy. Validation experiments include TRUS-guided needle targeting accuracy tests. This paper outlines the entire process from the calibration to image-guided targeting. Freehand TRUS-guided prostate biopsy is the primary method of diagnosing prostate cancer, with over 1.2 million procedures performed annually in the U.S. alone. However, freehand biopsy is a highly challenging procedure with subjective quality control. As such, biopsy devices are emerging to assist the physician. Here, we present a method that uses robotic TRUS manipulation. A 2-D TRUS probe is supported by a 4-degree-of-freedom robot. The robot performs ultrasound scanning, enabling 3-D reconstructions. Based on the images, the robot orients a needle guide on target for biopsy. The biopsy is acquired manually through the guide. In vitro tests showed that the 3-D images were geometrically accurate, and an image-based needle targeting accuracy was 1.55 mm. These validate the probe calibration presented and the overall robotic system for needle targeting. Targeting accuracy is sufficient for targeting small, clinically significant prostatic cancer lesions, but actual in vivo targeting will include additional error components that will have to be determined.

Formulation of Ionic-Liquid Electrolyte To Expand the Voltage Window of Supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Van Aken, Katherine L.; Beidaghi, Majid; Gogotsi, Yury

2015-03-18

An effective method to expand the operating potential window (OPW) of electrochemical capacitors based on formulating the ionic-liquid (IL) electrolytes is reported. Using model electrochemical cells based on two identical onion-like carbon (OLC) electrodes and two different IL electrolytes and their mixtures, it was shown that the asymmetric behavior of the electrolyte cation and anion toward the two electrodes limits the OPW of the cell and therefore its energy density. Also, a general solution to this problem is proposed by formulating the IL electrolyte mixtures to balance the capacitance of electrodes in a symmetric supercapacitor.

A low-level needle counter

International Nuclear Information System (INIS)

Fujita, Y.; Taguchi, Y.; Imamura, M.; Inoue, T.; Tanaka, S.

1977-01-01

A small end-window type gas-flow counter which has a sharpened needle (anode) against the end-window plane (cathode) was developed for low-level counting of β particles to the amount of less than one count per hour in solid sources of relatively high specific activity. The advantage of the needle counter for low-level work is that being of a conical shape the active volume as against the window area is small. The background count rate of 0.0092+-0.0005 cpm was obtained for a 10 mm dia needle counter operating in GM mode and in anticoincidence with a well-type NaI(Tl) guard crystal with massive shields. The counter design and the counter characteristics are presented in detail. The needle counter is simple in design, low-cost and stable in long time operation. (author)

Processing and Characterization of Needled Carbon Composites

Science.gov (United States)

2015-12-01

needle is used to insert high strength yarns (i.e., threads) through the dry fabric or prepreg laminate , leaving a loose thread loop underneath [9-11...capability which uses commercially-available felting needles to insert z-fibers into composite laminates at different angles (±45/90°) relative to the... laminate plane. Previous work with needled glass/epoxy composites has shown a 270% improvement in Mode I interlaminar fracture toughness when needled

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.

Needle thoracostomy in the treatment of a tension pneumothorax in trauma patients: what size needle?

Science.gov (United States)

Zengerink, Imme; Brink, Peter R; Laupland, Kevin B; Raber, Earl L; Zygun, Dave; Kortbeek, John B

2008-01-01

A tension pneumothorax requires immediate decompression using a needle thoracostomy. According to advanced trauma life support guidelines this procedure is performed in the second intercostal space (ICS) in the midclavicular line (MCL), using a 4.5-cm (2-inch) catheter (5-cm needle). Previous studies have shown a failure rate of up to 40% using this technique. Case reports have suggested that this high failure rate could be because of insufficient length of the needle. To analyze the average chest wall thickness (CWT) at the second ICS in the MCL in a trauma population and to evaluate the length of the needle used in needle thoracostomy for emergency decompression of tension pneumothoraces. Retrospective review of major trauma admissions (Injury Severity Score >12) at the Foothills Medical Centre in Calgary, Canada, who underwent a computed tomography chest scan admitted in the period from October 2001 until March 2004. Subgroup analysis on men and women, /=40 years of age was defined a priori. CWT was measured to the nearest 0.01 cm at the second ICS in the MCL. The mean CWT in the 604 male patients and 170 female patients studied averaged 3.50 cm at the left second ICS MCL and 3.51 cm on the right. The mean CWT was significantly higher for women than men (p 4.5 cm and 24.1% to 35.4% of the women studied. A catheter length of 4.5 cm may not penetrate the chest wall of a substantial amount (9.9%-35.4%) of the population, depending on age and gender. This study demonstrates the need for a variable needle length for relief of a tension pneumothorax in certain population groups to improve effectiveness of needle thoracostomy.

Experiences with a new breast localisation needle

International Nuclear Information System (INIS)

Hergan, K.; Amann, T.; Doringer, W.; Hollenstein, P.

1990-01-01

In view of the increasing number of biopsies of non-palpable lesions of the female breast we found an ideal localisation system in the Hawkins breast localisation needle. Localisation was successful without technical problems in 31 out of 34 patients. The special advantages of the needle are its stability in position and excellent manoeverability due to the construction of the needle. The very simple handling of the needle is an advantage not only for the radiologist but also for the surgeon. (orig.) [de

Embedded Ultrathin Cluster Electrodes for Long-Term Recordings in Deep Brain Centers.

Directory of Open Access Journals (Sweden)

Leila Etemadi

Full Text Available Neural interfaces which allow long-term recordings in deep brain structures in awake freely moving animals have the potential of becoming highly valuable tools in neuroscience. However, the recording quality usually deteriorates over time, probably at least partly due to tissue reactions caused by injuries during implantation, and subsequently micro-forces due to a lack of mechanical compliance between the tissue and neural interface. To address this challenge, we developed a gelatin embedded neural interface comprising highly flexible electrodes and evaluated its long term recording properties. Bundles of ultrathin parylene C coated platinum electrodes (N = 29 were embedded in a hard gelatin based matrix shaped like a needle, and coated with Kollicoat™ to retard dissolution of gelatin during the implantation. The implantation parameters were established in an in vitro model of the brain (0.5% agarose. Following a craniotomy in the anesthetized rat, the gelatin embedded electrodes were stereotactically inserted to a pre-target position, and after gelatin dissolution the electrodes were further advanced and spread out in the area of the subthalamic nucleus (STN. The performance of the implanted electrodes was evaluated under anesthesia, during 8 weeks. Apart from an increase in the median-noise level during the first 4 weeks, the electrode impedance and signal-to-noise ratio of single-units remained stable throughout the experiment. Histological postmortem analysis confirmed implantation in the area of STN in most animals. In conclusion, by combining novel biocompatible implantation techniques and ultra-flexible electrodes, long-term neuronal recordings from deep brain structures with no significant deterioration of electrode function were achieved.

21 CFR 868.5150 - Anesthesia conduction needle.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia conduction needle. 868.5150 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5150 Anesthesia conduction needle. (a) Identification. An anesthesia conduction needle is a device used to inject local anesthetics into a patient to...

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....

[Professor WU Zhongchao's experience of penetration needling].

Science.gov (United States)

Zhang, Ning; Wang, Bing; Zhou, Yu

2016-08-12

Professor WU Zhongchao has unique application of penetration needling in clinical treatment. Professor WU applies penetration needling along meridians, and the methods of penetration needling include self-meridian penetration, exterior-interior meridian penetration, identical-name meridian penetration, different meridian penetration. The meridian differentiation is performed according to different TCM syndromes, locations and natures of diseases and acupoint nature, so as to make a comprehensive assessment. The qi movement during acupuncture is focused. In addition, attention is paid on anatomy and long-needle penetration; the sequence and direction of acupuncture is essential, and the reinforcing and reducing methods have great originality, presented with holding, waiting, pressing and vibrating. Based on classical acupoint, the acupoint of penetration needling is flexible, forming unique combination of acupoints.

EUS needle identification comparison and evaluation (NICE) study (with videos)

Science.gov (United States)

Tang, Shou-jiang; Vilmann, Andreas S.; Saftoiu, Adrian; Wang, Wanmei; Streba, Costin; Fink, Peter P.; Griswold, Michael; Wu, Ruonan; Dietrich, Christoph F.; Jenssen, Christian; Hocke, Michael; Kantowski, Marcus; Pohl, Jürgen; Fockens, Paul; Annema, Jouke T.; van der Heijden, Erik H.F.M.; Havre, Roald Flesland; Pham, Khanh Do-Cong; Kunda, Rastislav; Deprez, Pierre H.; Mariana, Jinga; Vazquez-Sequeiros, Enrique; Larghi, Alberto; Buscarini, Elisabetta; Fusaroli, Pietro; Lahav, Maor; Puri, Rajesh; Garg, Pramod Kumar; Sharma, Malay; Maluf-Filho, Fauze; Sahai, Anand; Brugge, William R.; Lee, Linda S.; Aslanian, Harry R.; Wang, Andrew Y.; Shami, Vanessa M.; Markowitz, Arnold; Siddiqui, Ali A.; Mishra, Girish; Scheiman, James M.; Isenberg, Gerard; Siddiqui, Uzma D.; Shah, Raj J.; Buxbaum, James; Watson, Rabindra R.; Willingham, Field F.; Bhutani, Manoop S.; Levy, Michael J.; Harris, Cynthia; Wallace, Michael B.; Nolsøe, Christian Pállson; Lorentzen, Torben; Bang, Niels; Sørensen, Sten Mellerup; Gilja, Odd Helge; D’Onofrio, Mirko; Piscaglia, Fabio; Gritzmann, Norbert; Radzina, Maija; Sparchez, Zeno Adrian; Sidhu, Paul S.; Freeman, Simon; McCowan, Timothy C.; de Araujo, Cyrillo Rodrigues; Patel, Akash; del Ali, Mohammad A; Campbell, Garth; Chen, Edward; Vilmann, Peter

2017-01-01

Background and Aims Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) or biopsy is widely practiced. Optimal sonographic visualization of the needle is critical for image guided interventions. There are several commercially available needles but no bench-top testing and direct comparison of these needles to reveal their inherent echogenicity. The aims are to provide bench-top data that can be used to guide clinical applications and to promote future device research and development. Methods Descriptive bench-top testing and comparison. Bench-top testing of 8 commonly used EUS-FNA needles (all of 22 gauge in size): SonoTip Pro Control (Medi-Globe); Expect Slimline (Boston Scientific); EchoTip, EchoTip Ultra, EchoTip ProCore High Definition, (Cook Medical); ClearView (Conmed); EZ Shot2 (Olympus); BNX (Beacon Endoscopic); and 2 new prototype needles that are coated by echogenic polymers by Medi-Globe. Blinded evaluation of standardized and unedited videos by 43 EUS endoscopists and 17 radiologists specialized in gastrointestinal ultrasound examination that is unfamiliar with EUS needle devices. Results There was no significant difference in the ratings and rankings of these needles between endosonographers and radiologists. Overall, one prototype needle was rated as the best, ranking 10% to 40% higher than all other needles (p<0.01). Among the commercially available needles, the EchoTip Ultra needle and the ClearView needle were top choices. The EZ Shot 2 needle was ranked statistically lower than other needles (30%–75% worse, p<0.001). Conclusions All FNA needles have their inherent and different echogenicity, and these differences are similarly recognized by EUS endoscopists and radiologists. Needles with polymeric coating from the entire shaft to the needle tip may offer better echogenicity. PMID:26873530

Effect of bidirectional rotation of an acupuncture needle at LI10 on acupuncture needle sensation and experimentally-induced contact heat pain in healthy human volunteers.

Science.gov (United States)

Benham, Alex; Johnson, Mark I

2014-06-01

There is insufficient evidence of a relationship between acupuncture needle sensations (de qi) and hypoalgesia. The aim of this study was to investigate the effects of bidirectional needle rotation at LI10 on acupuncture needle sensations and heat pain thresholds. Twenty-two healthy participants received one acupuncture needle at LI10 with bidirectional rotation of the needle in one experimental session and one acupuncture needle at LI10 with mock rotation in a separate session, in a randomised order. Measurements of heat pain thresholds were taken before needle insertion, during needle retention and 15 min after needle removal. At each measurement time point, participants rated needle sensations using the Massachusetts Acupuncture Sensation Scale (MASS) and a visual analogue scale (VAS) of overall intensity of needle sensation. Bidirectional needle rotation produced significantly higher scores for VAS, MASStotal, MASSpain and MASSsensation compared with mock rotation (all psensation and change in pain threshold after needling was only found when data from mock and rotation interventions were combined. Needle rotation increases the magnitude of hypoalgesia. There is tentative evidence that needle sensation may be associated with the amount of change in pain threshold. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Photosensitive-polyimide based method for fabricating various neural electrode architectures

Directory of Open Access Journals (Sweden)

Yasuhiro X Kato

2012-06-01

Full Text Available An extensive photosensitive polyimide (PSPI-based method for designing and fabricating various neural electrode architectures was developed. The method aims to broaden the design flexibility and expand the fabrication capability for neural electrodes to improve the quality of recorded signals and integrate other functions. After characterizing PSPI’s properties for micromachining processes, we successfully designed and fabricated various neural electrodes even on a non-flat substrate using only one PSPI as an insulation material and without the time-consuming dry etching processes. The fabricated neural electrodes were an electrocorticogram electrode, a mesh intracortical electrode with a unique lattice-like mesh structure to fixate neural tissue, and a guide cannula electrode with recording microelectrodes placed on the curved surface of a guide cannula as a microdialysis probe. In vivo neural recordings using anesthetized rats demonstrated that these electrodes can be used to record neural activities repeatedly without any breakage and mechanical failures, which potentially promises stable recordings for long periods of time. These successes make us believe that this PSPI-based fabrication is a powerful method, permitting flexible design and easy optimization of electrode architectures for a variety of electrophysiological experimental research with improved neural recording performance.

Observations of needle-tissue interactions

NARCIS (Netherlands)

Misra, Sarthak; Reed, Kyle B.; Ramesh, K.T.; Okamura, Allison M.

2009-01-01

Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In this study, we present an analytical model for the loads developed at the bevel tip during needle-tissue interaction. The model calculates the loads based on the geometry of the bevel edge and gel material

Current status of core needle biopsy of the thyroid

Energy Technology Data Exchange (ETDEWEB)

Baek, Jung Hwan [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

2017-04-15

Thyroid nodules are a common clinical problem. Fine-needle aspiration (FNA) and large-needle biopsy have been used to diagnose thyroid nodules. Before the 1980s, large-needle biopsy was the standard procedure for the thyroid, but FNA became the standard diagnostic tool in the 1980s because it is a safe procedure that leads to accurate diagnoses. With advances in core needle biopsy (CNB) devices (i.e., spring-activated core needles) and development of high-resolution ultrasound, it has become possible to make accurate diagnoses while minimizing complications. Although 18- to 21-gauge core needles can be used to biopsy thyroid nodules, 18-gauge needles are most commonly used in Korea. The relationships among the size of the needle, the number of core specimens, and diagnostic accuracy have not yet been conclusively established, but the general tendency is that thinner needles cause less damage to the normal thyroid, but allow a smaller amount of thyroid tissue to be biopsied to be obtained. These relationships may be validated in the future.

Mesoporous NiCo2O4 nano-needles supported by 3D interconnected carbon network on Ni foam for electrochemical energy storage

Science.gov (United States)

Lu, Congxiang; Liu, Wen-wen; Pan, Hui; Tay, Beng Kang; Wang, Xingli; Liang, Kun; Wei, Xuezhe

2018-05-01

In this work, a three dimensional (3D) interconnected carbon network consisting of ultrathin graphite (UG) and carbon nanotubes (CNTs) on Ni foam is fabricated and employed as a novel type of substrate for mesoporous NiCo2O4 nano-needles. The successfully synthesized NiCo2O4 nano-needles/CNTs/UG on Ni foam has many advantages including facile electrolyte access and direct conducting pathways towards current collectors, which enable it to be a promising electrode material in battery-like electrochemical energy storage. Encouragingly, a high capacity of 135.1 mAh/g at the current density of 1 A/g, superior rate performance and also stable cycling for 1200 cycles at the current density of 5 A/g have been demonstrated in this novel material.

The standardized EEG electrode array of the IFCN.

Science.gov (United States)

Seeck, Margitta; Koessler, Laurent; Bast, Thomas; Leijten, Frans; Michel, Christoph; Baumgartner, Christoph; He, Bin; Beniczky, Sándor

2017-10-01

Standardized EEG electrode positions are essential for both clinical applications and research. The aim of this guideline is to update and expand the unifying nomenclature and standardized positioning for EEG scalp electrodes. Electrode positions were based on 20% and 10% of standardized measurements from anatomical landmarks on the skull. However, standard recordings do not cover the anterior and basal temporal lobes, which is the most frequent source of epileptogenic activity. Here, we propose a basic array of 25 electrodes including the inferior temporal chain, which should be used for all standard clinical recordings. The nomenclature in the basic array is consistent with the 10-10-system. High-density scalp EEG arrays (64-256 electrodes) allow source imaging with even sub-lobar precision. This supplementary exam should be requested whenever necessary, e.g. search for epileptogenic activity in negative standard EEG or for presurgical evaluation. In the near future, nomenclature for high density electrodes arrays beyond the 10-10 system needs to be defined, to allow comparison and standardized recordings across centers. Contrary to the established belief that smaller heads needs less electrodes, in young children at least as many electrodes as in adults should be applied due to smaller skull thickness and the risk of spatial aliasing. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

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...

STUDY & ANALYSIS OF MICRO NEEDLE MATERIAL BY ANSYS

OpenAIRE

Santosh Kumar Singh*, Prabhat Sinha, N.N. Singh, Nagendra Kumar

2017-01-01

In this research the concept of design and analysis, silicon and stainless steel based on hollow micro-needles for transdermal drug delivery(TDD) have been evaluated by Using ANSYS & computational fluid dynamic (CFD), structural. Micro fluidic analysis has performed to ensure the micro-needles design suitability for Drug delivery. The effect of axial and transverse load on single and micro-needle array has investigated with the mechanical properties of micro-needle. The analysis predicte...

The efficacy of an ultrasound-guided core needle biopsy with an 18G cutting needle for the diagnosis of pancreatic diseases

International Nuclear Information System (INIS)

Jung, Sung Hwa; Park, Won Kyu; Chang, Jay Chun; Kim, Jae Woon; Cho, Jae Ho; Jang, Han Won; Lee, Jae Kyo; Choi, Joon Hyuk

2008-01-01

The objective of this study is to evaluate the efficacy and safety of an ultrasound-guided core needle biopsy with an 18G cutting needle in patients suspected of having a pancreatic disease by analyzing the diagnostic performance and complication rate. The study population comprised 35 consecutive patients who underwent an ultrasound-guided core needle biopsy using a high-speed biopsy gun accompanied with an 18G cutting-type needle between May of 2001 and October of 2005. The diagnostic performance (i.e., the acquisition rate and diagnostic accuracy) and complications associated with core needle biopsies were evaluated for its efficacy and safety. Thirty-six sessions of ultrasound-guided core needle biopsies were performed in 35 consecutive patients. All patients, except two (serous cystadenoma and autoimmune pancreatitis) were diagnosed with various subtypes of pancreatic cancer. The acquisition rate and diagnostic accuracy were 97% (35/36) and 94% (34/36), respectively. A complication occurred only in one patient (3%), which further proved to be a delayed complication (i.e., needle tract implantation). According to our findings, the ultrasound-guided core needle biopsy is a viable and safe method for the diagnosis of pancreatic diseases. Moreover, it enables the diagnosis of the pancreatic cancer subtype

NPIP: A skew line needle configuration optimization system for HDR brachytherapy

International Nuclear Information System (INIS)

Siauw, Timmy; Cunha, Adam; Berenson, Dmitry; Atamtürk, Alper; Hsu, I-Chow; Goldberg, Ken; Pouliot, Jean

2012-01-01

Purpose: In this study, the authors introduce skew line needle configurations for high dose rate (HDR) brachytherapy and needle planning by integer program (NPIP), a computational method for generating these configurations. NPIP generates needle configurations that are specific to the anatomy of the patient, avoid critical structures near the penile bulb and other healthy structures, and avoid needle collisions inside the body. Methods: NPIP consisted of three major components: a method for generating a set of candidate needles, a needle selection component that chose a candidate needle subset to be inserted, and a dose planner for verifying that the final needle configuration could meet dose objectives. NPIP was used to compute needle configurations for prostate cancer data sets from patients previously treated at our clinic. NPIP took two user-parameters: a number of candidate needles, and needle coverage radius, δ. The candidate needle set consisted of 5000 needles, and a range of δ values was used to compute different needle configurations for each patient. Dose plans were computed for each needle configuration. The number of needles generated and dosimetry were analyzed and compared to the physician implant. Results: NPIP computed at least one needle configuration for every patient that met dose objectives, avoided healthy structures and needle collisions, and used as many or fewer needles than standard practice. These needle configurations corresponded to a narrow range of δ values, which could be used as default values if this system is used in practice. The average end-to-end runtime for this implementation of NPIP was 286 s, but there was a wide variation from case to case. Conclusions: The authors have shown that NPIP can automatically generate skew line needle configurations with the aforementioned properties, and that given the correct input parameters, NPIP can generate needle configurations which meet dose objectives and use as many or fewer

Assessing the degradation of compliant electrodes for soft actuators

Science.gov (United States)

Rosset, Samuel; de Saint-Aubin, Christine; Poulin, Alexandre; Shea, Herbert R.

2017-10-01

We present an automated system to measure the degradation of compliant electrodes used in dielectric elastomer actuators (DEAs) over millions of cycles. Electrodes for DEAs generally experience biaxial linear strains of more than 10%. The decrease in electrode conductivity induced by this repeated fast mechanical deformation impacts the bandwidth of the actuator and its strain homogeneity. Changes in the electrode mechanical properties lead to reduced actuation strain. Rather than using an external actuator to periodically deform the electrodes, our measurement method consists of measuring the properties of an electrode in an expanding circle DEA. A programmable high voltage power supply drives the actuator with a square signal up to 1 kHz, periodically actuating the DEA, and thus stretching the electrodes. The DEA strain is monitored with a universal serial bus camera, while the resistance of the ground electrode is measured with a multimeter. The system can be used for any type of electrode. We validated the test setup by characterising a carbon black/silicone composite that we commonly use as compliant electrode. Although the composite is well-suited for tens of millions of cycles of actuation below 5%, we observe important degradation for higher deformations. When activated at a 20% radial strain, the electrodes suffer from important damage after a few thousand cycles, and an inhomogeneous actuation is observed, with the strain localised in a sub-region of the actuator only.

Electrode-Skin contact impedance: In vivo measurements on an ovine model

International Nuclear Information System (INIS)

Nguyen, D T; Kosobrodov, R; Jin, C; McEwan, A; Barry, M A; Chik, W; Thiagalingam, A; Oh, T I

2013-01-01

The problem of electrical impedance between the skin and the electrode is an on-going challenge in bio-electronics. This is particularly true in the case of Electrical Impedance Tomography (EIT), which uses a large number of skin-contact electrodes and is very sensitive to noise. In the present article, contact impedance is measured and compared for a range of electrodes placed on the thorax of an ovine model. The study has been approved by the Westmead Hospital Animal Ethics Committee. The electrode models that were employed in the research are Ag/AgCl electrodes (E1), commonly used for ECG and EIT measurements in both humans and animal models, stainless steel crocodile clips (E2), typically used on animal models, and novel multi-point dry electrodes in two modifications: bronze plated (E3) and nickel plated (E4). Further, since the contact impedance is mostly attributed to the acellular outer layer of the skin, in our experiment, we attempted to study the effect of this layer by comparing the results when the skin is intact and when electrodes are introduced underneath the skin through small cuts. This boundary effect was assessed by comparison of measurements obtained during E2 skin surface contact, and sub-cutaneous contact (E5). Twelve gauge intradermal needles were also tested as an electrode (E6). The full impedance spectrum, from 500 Hz to 300 kHz, was recorded, analysed and compared. As expected, the contact impedance in the more invasive cases, i.e the electrodes under the skin, is significantly lower than in the non-invasive cases. At the frequency of 50 kHz which is commonly used in lung EIT acquisition, electrodes E3, E4 and E6 demonstrated contact impedance of less than 200 Ω, compared to more than 400 Ω measured for electrodes E1, E2 and E5. In conclusion, the novel multipoint electrodes proved to be best suited for EIT purposes, because they are non-invasive and have lower contact impedance than Ag/AgCl and crocodile clips, in both invasive and

Migration of innumerable chronically retained acupuncture needles

Directory of Open Access Journals (Sweden)

Frances Lazarow, MD

2017-09-01

Full Text Available We present a case of a 50-year-old female with a 2-day history of back and abdominal pain who was discovered to have innumerable chronically retained acupuncture needles, which had migrated throughout her abdomen and pelvis. Although many of these needles were in precarious positions, including the epidural space, renal parenchyma, small bowel, and vasculature, there was no evidence for acute injury. We also briefly discuss evidence for the magnetic resonance imaging compatibility of acupuncture needles. Although a rare complication, given the high frequency of acupuncture therapy in the United States, physicians must be aware of the potential for retained and migrated needles.

Needle muscle biopsy and its application

Directory of Open Access Journals (Sweden)

Meng-long CHEN

2015-07-01

Full Text Available Needle muscle biopsy is a straightforward and reliable minimally-invasive technique. During the past century, the needle biopsy can provide adequate samples and the technique has gradually gained wider acceptance. Compared with open biopsy, needle biopsy is less traumatic, with low rate of complications, and is suitable for the identifications and evaluations of muscular dystrophy, inflammatory myopathies and systemic diseases involving muscles, specially for infants and young children. Domestic insiders should be encouraged to apply this technique. DOI: 10.3969/j.issn.1672-6731.2015.06.003 

Development of atmospheric pressure plasma needle jet for sterilization applications

Science.gov (United States)

Elfa, Rizan Rizon; Ahmad, Mohd Khairul; Soon, Chin Fhong; Sahdan, Mohd Zainizan; Lias, Jais; Wibowo, Kusnanto Mukti; Bakar, Ahmad Shuhaimi Abu; Arshad, Mohd Khairuddin Md; Hashim, Uda; Nayan, Nafarizal

2017-09-01

Inactivation of bacteria or sterilization has been a major issue in the medical field, especially regarding of human safety, whereby, in a huge scenario fatality can be caused by hazardous bacteria. Often, E-coli as gram-negative bacteria are selected as a key indicator of proper sterilization process as E-coli is tough and dormant bacteria. The technology in sterilization has moved on from chemical, wet and irradiation sterilization to a high promising device such as atmospheric pressure plasma needle jet (APPNJ). It has been reported that atmospheric pressure plasma has provided bundle of advantages over earlier sterilization process. The APPNJ is developed in our lab using high frequency and high voltage neon transformer power supply connected to copper needle and copper sheet electrodes. The gas discharge is Ar gas flowing at 40 L/min through a quartz glass tube. The E-coli bacteria are self-cultured from waste water and then treated with APPNJ. The treatment processes are run into two difference gaps between the plasma orifice and sample with various treatment times. Only 40s is required by direct treatment to achieve 100% killing of E-coli. On the other hand, indirect treatment has inactivated 50% of the E-coli in 40s. In this study, direct and indirect effect of APPNJ to the E-coli can be observed which can be utilized into sterilization of bio-compatible material applications.

Investigation of environmental pollution with pine needles by NAA

Energy Technology Data Exchange (ETDEWEB)

Lee, Kil Yong; Yoon, Yoon Yeol; Yang, Myung Kwon; Shim, Sang Kwon; Seo, Bum Kyoung [Korea Inst. of Geosience and Mineral Resources, Environmental Geology Division, Daejeon (Korea); Chung, Yong Sam [Korea Atomic Energy Research Inst., HANARO Center, Daejeon (Japan)

2002-04-01

NAA was studied to precision analysis of metallic elements in pine needle. The pine needle was investigated whether it can be feasible or not as a bio-monitor. Only one year old needle was taken from three different regions of urban, suburban and rural area in four seasons. The needle sample was divided with two aliquots, and then one was cleaned and the other was not. Loss and contamination of analytes were cautiously minimized when the needle was sample and transferred from mountain to laboratory and prepared for NAA. Some elements such as As, Br, Ce, W, Zn have shown different characteristics with regions and seasons as well as surface cleaning. It is found that about twenty elements in pine needle could be simply analyzed by NAA and the pine needle could be suitable as a bio-monitor for the monitoring of environmental pollution in Korea. (author)

PVA matches human liver in needle-tissue interaction.

Science.gov (United States)

de Jong, Tonke L; Pluymen, Loes H; van Gerwen, Dennis J; Kleinrensink, Gert-Jan; Dankelman, Jenny; van den Dobbelsteen, John J

2017-05-01

Medical phantoms can be used to study needle-tissue interaction and to train medical residents. The purpose of this research is to study the suitability of polyvinyl alcohol (PVA) as a liver tissue mimicking material in terms of needle-tissue interaction. Insertions into ex-vivo human livers were used for reference. Six PVA samples were created by varying the mass percentage of PVA to water (4m% and 7m%) and the number of freeze-thaw cycles (1, 2 and 3 cycles, 16hours of freezing at -19°C, 8hours of thawing). The inner needle of an 18 Gauge trocar needle with triangular tip was inserted 13 times into each of the samples, using an insertion velocity of 5 mm/s. In addition, 39 insertions were performed in two ex-vivo human livers. Axial forces on the needle were captured during insertion and retraction and characterized by friction along the needle shaft, peak forces, and number of peak forces per unit length. The concentration of PVA and the number of freeze-thaw cycles both influenced the mechanical interaction between needle and specimen. Insertions into 4m% PVA phantoms with 2 freeze-thaw cycles were comparable to human liver in terms of estimated friction along the needle shaft and the number of peak forces. Therefore, these phantoms are considered to be suitable liver mimicking materials for image-guided needle interventions. The mechanical properties of PVA hydrogels can be influenced in a controlled manner by varying the concentration of PVA and the number of freeze-thaw cycles, to mimic liver tissue characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exploring needle anxiety among students attending a Nigerian ...

African Journals Online (AJOL)

Needle anxiety, a form of specific phobia refers to an intense fear of needles used for various medical procedures. It may result in the avoidance of such needle-involving procedures like intramuscular injections or vaccinations. About 4-8% of children and adolescents are said to generally suffer some form of anxiety.

Observations on rotating needle insertions using a brachytherapy robot

International Nuclear Information System (INIS)

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

2007-01-01

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

Brainstem auditory evoked potentials in healthy cats recorded with surface electrodes

Directory of Open Access Journals (Sweden)

Mihai Musteata

2013-01-01

Full Text Available The aim of this study was to evaluate the brainstem auditory evoked potentials of seven healthy cats, using surface electrodes. Latencies of waves I, III and V, and intervals I–III, I–V and III–V were recorded. Monaural and binaural stimulation of the cats were done with sounds ranging between 40 and 90 decibel Sound Pressure Level. All latencies were lower than those described in previous studies, where needle electrodes were used. In the case of binaural stimulation, latencies of waves III and V were greater compared to those obtained for monaural stimulation (P P > 0.05. Regardless of the sound intensity, the interwave latency was constant (P > 0.05. Interestingly, no differences were noticed for latencies of waves III and V when sound intensity was higher than 80dB SPL. This study completes the knowledge in the field of electrophysiology and shows that the brainstem auditory evoked potentials in cats using surface electrodes is a viable method to record the transmission of auditory information. That can be faithfully used in clinical practice, when small changes of latency values may be an objective factor in health status evaluation.

Insertion mechanics of bioinspired needles into soft tissues.

Science.gov (United States)

Sahlabadi, Mohammad; Khodaei, Seyedvahid; Jezler, Kyle; Hutapea, Parsaoran

2017-12-22

Most studies to date confirm that any increase in the needle insertion force increases the damage to the tissue. When it comes to brain tissue, even minor damage can cause a long-lasting traumatic brain injury. Thus there is a great demand for innovative minimally invasive needles among the medical community. In our previous studies a novel bioinspired needle design with specially designed barbs was used to perform insertion tests into Polyvinyl chloride (PVC) tissue-mimicking gels, in which it decreased the insertion force by as much as 25%. In this work, bioinspired needles were designed using a CAD software, and were then manufactured using a 3 D printer. The insertion tests into bovine brain and liver were then performed to further investigate the performance of our bioinspired needles in real tissues. Our results show that there was a 10-25% decrease in the insertion force for insertions into bovine brain, and a 35-45% reduction in the insertion force for insertions into bovine liver using the proposed bioinspired needles. The reduction in the insertion force is due to the decrease in the friction force of the bioinspired needle with the bovine tissues, and its results are consistent with our previous results.

High-pressure needle interface for thermoplastic microfluidics.

Science.gov (United States)

Chen, C F; Liu, J; Hromada, L P; Tsao, C W; Chang, C C; DeVoe, D L

2009-01-07

A robust and low dead volume world-to-chip interface for thermoplastic microfluidics has been developed. The high pressure fluidic port employs a stainless steel needle inserted into a mating hole aligned to an embedded microchannel, with an interference fit used to increase pressure resistance. Alternately, a self-tapping threaded needle screwed into a mating hole is also demonstrated. In both cases, the flat bottom needle ports seat directly against the microchannel substrate, ensuring low interfacial dead volumes. Low dispersion is observed for dye bands passing the interfaces. The needle ports offer sufficient pull-out forces for applications such as liquid chromatography that require high internal fluid pressures, with the epoxy-free interfaces compatible with internal microchannel pressures above 40 MPa.

Computed tomography guided needle biopsy: experience from 1,300 procedures

Energy Technology Data Exchange (ETDEWEB)

Chojniak, Rubens; Isberner, Rony Klaus; Viana, Luciana Marinho; Yu, Liao Shin; Aita, Alessandro Amorim; Soares, Fernando Augusto [Hospital do Cancer A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Radiologia e Patologia

2006-01-15

Context and objective: computed tomography (CT) guided biopsy is widely accepted as effective and safe for diagnosis in many settings. Accuracy depends on target organ and needle type. Cutting needles present advantages over fine needles. This study presents experience from CT guided biopsies performed at an oncology center. Design and setting: retrospective study at Hospital do Cancer A. C. Camargo, Sao Paulo.Methods: 1,300 consecutive CT guided biopsies performed between July 1994 and February 2000 were analyzed. Nodules or masses were suspected as primary malignancy in 845 cases (65%) or metastatic lesion in 455 (35%). 628 lesions were thoracic, 281 abdominal, 208 retroperitoneal, 134 musculoskeletal and 49 head/neck. All biopsies were performed by one radiologist or under his supervision: 765 (59%) with 22-gauge fine-needle/aspiration technique and 535 (41%) with automated 16 or 18-gauge cutting-needle biopsy. Results: adequate samples were obtained in 70-92% of fine-needle and 93-100% of cutting-needle biopsies. The specific diagnosis rates were 54-67% for fine-needle and 82-100% for cutting-needle biopsies, according to biopsy site. For any site, sample adequacy and specific diagnosis rate were always better for cutting-needle biopsy. Among 530 lung biopsies, there were 84 pneumothorax (16%) and two hemothorax (0.3%) cases, with thoracic drainage in 24 (4.9%). Among abdominal and retroperitoneal biopsies, there were two cases of major bleeding and one of peritonitis. Conclusion: both types of needle showed satisfactory results, but cutting-needle biopsy should be used when specific diagnosis is desired without greater incidence of complications. (author)

The Problem of Metal Needles in Acupuncture-fMRI Studies

Directory of Open Access Journals (Sweden)

Florian Beissner

2011-01-01

Full Text Available Acupuncture is a therapy based on sensory stimulation of the human body by means of metal needles. The exact underlying mechanisms of acupuncture have not been clarified so far. Functional magnetic resonance imaging (fMRI has become an important tool in acupuncture research. Standard acupuncture needles, which are made of ferromagnetic steel, however, are problematic in acupuncture-fMRI studies for several reasons, such as attraction by the scanner's magnetic field, significant image distortions and signal-dropouts, when positioned close to the head or even heating due to absorption of radio frequency (RF. The aim of this study was to compare two novel types of acupuncture needles with a standard needle for their effect on MRI image quality. The standard needle severely reduced image quality, when located inside the RF coil. The nonferromagnetic metal needle may pose a risk due to RF heating, while the plastic needle has a significantly larger diameter. In conclusion, our recommendations are: (1 standard needles should not be used in MRI; (2 Nonferromagnetic metal needles seem to be the best choice for acupoints outside of the transmitter coil; and (3 only plastic needles are suited for points inside the coil. Laser acupuncture may be a safe alternative, too.

Percutaneous CT-Guided Core Needle Biopsy Versus Fine Needle Aspiration in Diagnosing Pneumonia and Mimics of Pneumonia

International Nuclear Information System (INIS)

Thanos, Loukas; Galani, Panagiota; Mylona, Sophia; Pomoni, Maria; Mpatakis, Nikolaos

2004-01-01

The purpose of this study was to determine the diagnostic value of percutaneous core needle biopsy (CNB) relative to fine needle aspiration (FNA) in patients with pneumonia and pneumonia mimics. In this prospective study we present our experience with 48 thoracic FNAs and CNBs carried out on 48 patients with pneumonia and pneumonia mimics. Samples were obtained from all patients using both CNB (with an automated 18-G core biopsy needle and a gun) and FNA (with a 22-G needle). A specific diagnosis was made in 10/48 cases (20.83%) by FNA and in 42/48 (87.5%) by CNB. The main complications encountered were pneumothorax (n = 4) and hemoptysis (n = 2), yielding a total complication rate of 12.5%. We concluded that CNB using an automated biopsy gun results in a higher diagnostic accuracy for pneumonia and pneumonia mimic biopsies than FNA. Complications should be considered and proper patient observation should follow the procedure

High-Field MRI-Compatible Needle Placement Robot for Prostate Interventions

OpenAIRE

SU, Hao; CAMILO, Alex; COLE, Gregory A.; HATA, Nobuhiko; TEMPANY, Clare M.; FISCHER, Gregory S.

2011-01-01

This paper presents the design of a magnetic resonance imaging (MRI) compatible needle placement system actuated by piezoelectric actuators for prostate brachytherapy and biopsy. An MRI-compatible modular 3 degree-of-freedom (DOF) needle driver module coupled with a 3-DOF x-y-z stage is proposed as a slave robot to precisely deliver radioactive brachytherapy seeds under interactive MRI guidance. The needle driver module provides for needle cannula rotation, needle insertion and cannula retrac...

Free thyroxine in needle washout after fine needle aspiration biopsy of toxic thyroid nodules.

Science.gov (United States)

Raikov, Nikolai; Nonchev, Boyan; Chaushev, Borislav; Vjagova, Diyana; Todorov, Svetoslav; Bocheva, Yana; Malceva, Daniela; Vicheva, Snejinka; Raikova, Asyia; Argatska, Antoaneta; Raikov, Miroslav

2016-01-01

The main diagnostic tool for toxic adenomas (TA) is radionuclide imaging indicated in patients with evidence of thyroid nodules in combination with thyrotoxic syndrome. Thyroid ultrasound and fine-needle aspiration biopsy (FNAB) are widely used for the valuation of thyroid masses. There is no literature data concerning the utility of FNAB and related tests for the diagnosis of hyperfunctioning thyroid nodules. The purpose of this study is to determine the levels of free thyroxine (FT4) in the needle washout after FNAB of hot thyroid nodules. The results of our study show that the FT4 levels in needle washout from TA were significantly higher than the surrounding parenchyma and correlated with the hormonal changes in patients with thyroid hyperfunctioning nodules. Further studies on a large number of patients are needed to refine the diagnostic value of this method and evaluate its importance in quantitative risk assessment of thyroid autonomy.

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.

Ultrasound guided percutaneous fine needle aspiration biopsy ...

African Journals Online (AJOL)

)-guided percutaneous fine needle aspiration biopsy (PFNAB)/US-guided percutaneous needle core biopsy (PNCB) of abdominal lesions is efficacious in diagnosis, is helpful in treatment choice, to evaluate whether various other investigations ...

A retrospective analysis of ultrasound-guided large core needle ...

African Journals Online (AJOL)

2016-07-27

Jul 27, 2016 ... The different types of non-surgical breast biopsy procedures include: fine needle aspiration biopsy. (FNAB), core needle ... needle biopsies of breast lesions at a regional public hospital in ..... NCR_2009_FINAL.pdf. 2. Parikh J ...

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 micrometer....... While the orientation of the individual molecules in the needles is defined by the direction of surface dipoles, the localization on the surface, the length distribution as well as mutual distances can be adjusted via size and position of the laser focus spot.......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...

C-plane Reconstructions from Sheaf Acquisition for Ultrasound Electrode Vibration Elastography.

Science.gov (United States)

Ingle, Atul; Varghese, Tomy

2014-09-03

This paper presents a novel algorithm for reconstructing and visualizing ablated volumes using radiofrequency ultrasound echo data acquired with the electrode vibration elastography approach. The ablation needle is vibrated using an actuator to generate shear wave pulses that are tracked in the ultrasound image plane at different locations away from the needle. This data is used for reconstructing shear wave velocity maps for each imaging plane. A C-plane reconstruction algorithm is proposed which estimates shear wave velocity values on a collection of transverse planes that are perpendicular to the imaging planes. The algorithm utilizes shear wave velocity maps from different imaging planes that share a common axis of intersection. These C-planes can be used to generate a 3D visualization of the ablated region. Experimental validation of this approach was carried out using data from a tissue mimicking phantom. The shear wave velocity estimates were within 20% of those obtained from a clinical scanner, and a contrast of over 4 dB was obtained between the stiff and soft regions of the phantom.

A comparison of ultrasound guided fine needle aspiration cytology and core needle biopsy in evaluation of palpable breast lesions

International Nuclear Information System (INIS)

Altaf, H.N.; Farooqui, F.

2015-01-01

Objective: To compare ultrasound guided fine-needle aspiration cytology (FNAC) and core needle biopsy (CNB) in patients presenting with palpable breast lumps (PBLs), in terms of sensitivity and specificity, taking final histopathology as gold standard. Methodology: This cross-sectional study was conducted at Holy Family Hospital, Rawalpindi, Pakistan. Ultrasound guided FNAC and CNB were taken of all female patients with PBLs. The results were compared with final histopathology as gold standard. Data analysis was performed using SPSS software and chi-square test. Results: A total of 60 patients were included in the study. The mean age was 33.8 yrs. The sensitivity and specificity of ultrasound guided FNAC were 68.7% and 93.1%, respectively. The sensitivity and specificity of ultrasound guided CNB was 93.7% and 100%. The accuracy of FNAC was 86.2% and that of core needle biopsy was 98.3%. Conclusion: The ultrasound guided core needle biopsy can be used as an initial diagnostic test for the evaluation of all PBLs. Because of high negative predictive value core needle biopsy can replace surgical excision biopsy for benign lesions. (author)

Quantification of Tissue Trauma following Insulin Pen Needle Insertions in Skin

DEFF Research Database (Denmark)

Jensen, Casper Bo; Larsen, Rasmus; Vestergaard, Jacob Schack

Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop a computa......Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop...... a computational method to quantify tissue trauma based on skin bleeding and immune response. Method: Two common sized pen needles of 28G (0.36mm) and 32G (0.23mm) were inserted into skin of sedated LYD pigs prior to termination. Four pigs were included and a total of 32 randomized needle insertions were conducted...... diameter. Conclusion: A computational and quantitative method has been developed to assess tissue trauma following insulin pen needle insertions. Application of the method is tested by conduction of a needle diameter study. The obtained quantitative measures of tissue trauma correlate positively to needle...

Gallium Nitride Crystals: Novel Supercapacitor Electrode Materials.

Science.gov (United States)

Wang, Shouzhi; Zhang, Lei; Sun, Changlong; Shao, Yongliang; Wu, Yongzhong; Lv, Jiaxin; Hao, Xiaopeng

2016-05-01

A type of single-crystal gallium nitride mesoporous membrane is fabricated and its supercapacitor properties are demonstrated for the first time. The supercapacitors exhibit high-rate capability, stable cycling life at high rates, and ultrahigh power density. This study may expand the range of crystals as high-performance electrode materials in the field of energy storage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-Field MRI-Compatible Needle Placement Robot for Prostate Interventions

Science.gov (United States)

SU, Hao; CAMILO, Alex; COLE, Gregory A.; HATA, Nobuhiko; TEMPANY, Clare M.; FISCHER, Gregory S.

2014-01-01

This paper presents the design of a magnetic resonance imaging (MRI) compatible needle placement system actuated by piezoelectric actuators for prostate brachytherapy and biopsy. An MRI-compatible modular 3 degree-of-freedom (DOF) needle driver module coupled with a 3-DOF x-y-z stage is proposed as a slave robot to precisely deliver radioactive brachytherapy seeds under interactive MRI guidance. The needle driver module provides for needle cannula rotation, needle insertion and cannula retraction to enable the brachytherapy procedure with the preloaded needles. The device mimics the manual physician gesture by two point grasping (hub and base) and provides direct force measurement of needle insertion force by fiber optic force sensors. The fabricated prototype is presented and an experiment with phantom trials in 3T MRI is analyzed to demonstrate the system compatibility. PMID:21335868

Structure and photoluminescence properties of Ag-coated ZnO nano-needles

Energy Technology Data Exchange (ETDEWEB)

Li Xiaozhu, E-mail: Lixiaozhu1019@21cn.com [Department of Physics, Shaoguan University, Shaoguan, Guangdong 512005 (China) and Department of Physics and Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education, Wuhan University, Wuhan, Hubei 430072 (China); Wang Yongqian [Engineering Research Center of Nano-Geomaterials of Ministry of Education (China University of Geosciences), Wuhan, Hubei 430074 (China)

2011-05-12

Highlights: > ZnO nano-needles were synthesized by thermal oxidation. > Their surfaces were coated with Ag by pulse electro-deposition technique. > The uncoated and coated ZnO nano-needles were characterized. > The results showed that the prepared ZnO nano-needles have been coated with Ag successfully. > The photoluminescence spectrums of ZnO nano-needles with Ag-coated and uncoated were analyzed, finding that the Ag-coated ZnO nano-needles can increase the absorption of UV light. - Abstract: A large number of zinc oxide (ZnO) nano-needles were synthesized by thermal oxidation of pure zinc. The surfaces of ZnO nano-needles were coated with a layer of Ag by pulse electro-deposition technique. The uncoated and coated ZnO nano-needles were characterized by using the X-ray diffraction and the scanning electron microscope (SEM). The results showed that the uncoated samples were close-packed hexagonal structure, which showed needle-like morphology. Their average diameter is about 40 nm, lengths up to 5 {mu}m. At the same time we observed that the prepared ZnO nano-needles have been coated with Ag successfully. The photoluminescence spectrums of ZnO nano-needles with Ag-coated and uncoated were analyzed, finding that the uncoated ZnO nano-needles have two fluorescence peaks at 388 nm and 470.8 nm, respectively, the relative intensity of 143.4 and 93.61; and the Ag-coated ZnO nano-needles showed a pair of strong peaks at 387.4 nm and 405.2 nm, the relative intensity of 1366 and 1305, respectively, indicating that the Ag-coated ZnO nano-needles can increase the absorption of UV light.

Master-slave robotic system for needle indentation and insertion.

Science.gov (United States)

Shin, Jaehyun; Zhong, Yongmin; Gu, Chengfan

2017-12-01

Bilateral control of a master-slave robotic system is a challenging issue in robotic-assisted minimally invasive surgery. It requires the knowledge on contact interaction between a surgical (slave) robot and soft tissues. This paper presents a master-slave robotic system for needle indentation and insertion. This master-slave robotic system is able to characterize the contact interaction between the robotic needle and soft tissues. A bilateral controller is implemented using a linear motor for robotic needle indentation and insertion. A new nonlinear state observer is developed to online monitor the contact interaction with soft tissues. Experimental results demonstrate the efficacy of the proposed master-slave robotic system for robotic needle indentation and needle insertion.

Possibilities of the chemical analysis of Scots pine (Pinus sylvestris) needles

International Nuclear Information System (INIS)

Viksna, A.

1999-01-01

Scots pine (Pinus sylvestris L.) is a good bio indicator. This species is widely distributed in Europe, including Latvia, is easily identified, and is used in bio indication studies. It is known that the concentrations of most elements in needles change with time. These changes are connected to the processes involved in the uptake, transportation, storage and retranslocation of the elements. Scots pine keeps their needles for several years (3 to 4 years) and are suitable for the study of time related processes. The chemical composition of pine needles is used for the study the deposition and impact of air pollutants. Coniferous needles are covered with epicuticular wax, which act as a trap for airborne deposits. A comparison of chemical composition of pine needles that were unwashed and washed with chloroform made it possible to distinguish which elements were on the needles and to evaluate the character of pollution. The most important stage of the analysis of pine needles is sampling. Nutrient concentrations in the needles of coniferous trees have been shown to vary with the needle age and tree age, the phase of the annual physiological cycle, availability of nutrients in the soil and needle position within the crown. It is very important to take representative sample for the analysis. In the current work the trace element concentrations of the single needle were analysed by electrothermal atomic absorption spectrometry (ETAAS) and total reflection X-ray spectrometry (TXRF). The results of analysis showed that concentration of some elements depends from the position of needle within branch for the same needle age class. The concentrations of trace elements in the single needles within main shoot were more or less constant compare with other order shoots at given needle age class. Some higher variations in the elemental concentrations between single needles were observed in the tip part of main shoot. The actual distribution of the elements within a needle has

Robotic needle steering: design, modeling, planning, and image guidance

NARCIS (Netherlands)

Cowan, Noah J.; Goldberg, Ken; Chirikjian, Gregory S.; Fichtinger, Gabor; Alterovitz, Ron; Reed, Kyle B.; Kallem, Vinutha; Misra, Sarthak; Park, Wooram; Okamura, Allison M.; Rosen, Jacob; Hannaford, Blake; Satava, Richard M.

2010-01-01

This chapter describes how advances in needle design, modeling, planning, and image guidance make it possible to steer flexible needles from outside the body to reach specified anatomical targets not accessible using traditional needle insertion methods. Steering can be achieved using a variety of

[Novel echogenic needle for ultrasound-guided peripheral nerve block "Hakko type CCR"].

Science.gov (United States)

Takayama, Wataru; Yasumura, Rie; Kaneko, Takehiko; Kobayashi, Yoshiro; Kamada, Takaaki; Yoshikawa, Tamotsu; Aoyama, Yasuhiko

2009-04-01

A novel echogenic insulated nerve block needle (CCR-needle: Echogenic Needle Type CCR; Hakko, Japan) is commercially available since 2006 in Japan. This needle has three echogenic dimples, namely corner cube reflectors (CCR) on its tip. The CCR-needle will potentially provide a significant advantage for detecting the needle tip. In this report, we firstly evaluated this new disposable echogenic needle in simulation phantom, and demonstrated improved visibility of the needle tip. Afterwards, an interscalene brachial plexus block was performed on a male patient undergoing shoulder surgery. The needle insertion procedure was the "out of plane" ultrasound-guided technique using simultaneous electrical nerve stimulation. The surgery was successfully conducted without any complications.

Endoscopic Ultrasound Guided Rendezvous Drainage of Biliary Obstruction Using a New Flexible 19-Gauge Fine Needle Aspiration Needle.

Science.gov (United States)

Tang, Zhouwen; Igbinomwanhia, Efehi; Elhanafi, Sherif; Othman, Mohamed O

2016-01-01

Background and Aim. A successful endoscopic ultrasound guided rendezvous (EUS-RV) biliary drainage is dependent on accurate puncture of the bile duct and precise guide wire manipulation across the ampulla of Vater. We aim to study the feasibility of using a flexible 19-gauge fine aspiration needle in the performance of EUS-RV biliary drainage. Method. This is a retrospective case series of EUS-RV biliary drainage procedures at a single center. Patients who failed ERCP during the same session for benign or malignant biliary obstruction underwent EUS-RV using a flexible, nitinol covered, 19-gauge needle for biliary access and guide wire manipulation. Result. 24 patients underwent EUS-RV biliary drainage via extrahepatic access while 1 attempt was via intrahepatic access. The technical success rate was 80%, including 83.3% of cases via extrahepatic access. There was no significant difference in success rate of inpatient and outpatient procedures, benign or malignant indications, or type of guide wire used. Adverse events included mild pancreatitis (3 patients) and cholangitis (1 patient). Conclusion. A flexible 19-gauge needle for biliary access can be safe and effective when used to perform EUS-RV biliary drainage. Direct comparison between the nitinol needle and conventional metal needles in the performance of EUS guided biliary drainage is needed.

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.

Novel Double-Needle System That Can Prevent Intravascular Injection of Any Filler

Directory of Open Access Journals (Sweden)

Hsiang Huang, MD

2017-09-01

Full Text Available Summary:. A new type of needle system combines 2 parts, an inner needle and an outer needle. The inner needle is used for filler injection and the outer needle acts as a guiding needle that can observe blood reflow when inserting into the vessel lumen during injection process. This new needle system can be used for all kinds of filler, providing real time monitoring for physician and preventing intravascular injection of any filler.

Torsional Dynamics of Steerable Needles: Modeling and Fluoroscopic Guidance

Science.gov (United States)

Swensen, John P.; Lin, MingDe; Okamura, Allison M.; Cowan, Noah J.

2017-01-01

Needle insertions underlie a diversity of medical interventions. Steerable needles provide a means by which to enhance existing needle-based interventions and facilitate new ones. Tip-steerable needles follow a curved path and can be steered by twisting the needle base during insertion, but this twisting excites torsional dynamics that introduce a discrepancy between the base and tip twist angles. Here, we model the torsional dynamics of a flexible rod—such as a tip-steerable needle—during subsurface insertion and develop a new controller based on the model. The torsional model incorporates time-varying mode shapes to capture the changing boundary conditions inherent during insertion. Numerical simulations and physical experiments using two distinct setups—stereo camera feedback in semi-transparent artificial tissue and feedback control with real-time X-ray imaging in optically opaque artificial tissue— demonstrate the need to account for torsional dynamics in control of the needle tip. PMID:24860026

Structure and photoluminescence properties of Ag-coated ZnO nano-needles

International Nuclear Information System (INIS)

Li Xiaozhu; Wang Yongqian

2011-01-01

Highlights: → ZnO nano-needles were synthesized by thermal oxidation. → Their surfaces were coated with Ag by pulse electro-deposition technique. → The uncoated and coated ZnO nano-needles were characterized. → The results showed that the prepared ZnO nano-needles have been coated with Ag successfully. → The photoluminescence spectrums of ZnO nano-needles with Ag-coated and uncoated were analyzed, finding that the Ag-coated ZnO nano-needles can increase the absorption of UV light. - Abstract: A large number of zinc oxide (ZnO) nano-needles were synthesized by thermal oxidation of pure zinc. The surfaces of ZnO nano-needles were coated with a layer of Ag by pulse electro-deposition technique. The uncoated and coated ZnO nano-needles were characterized by using the X-ray diffraction and the scanning electron microscope (SEM). The results showed that the uncoated samples were close-packed hexagonal structure, which showed needle-like morphology. Their average diameter is about 40 nm, lengths up to 5 μm. At the same time we observed that the prepared ZnO nano-needles have been coated with Ag successfully. The photoluminescence spectrums of ZnO nano-needles with Ag-coated and uncoated were analyzed, finding that the uncoated ZnO nano-needles have two fluorescence peaks at 388 nm and 470.8 nm, respectively, the relative intensity of 143.4 and 93.61; and the Ag-coated ZnO nano-needles showed a pair of strong peaks at 387.4 nm and 405.2 nm, the relative intensity of 1366 and 1305, respectively, indicating that the Ag-coated ZnO nano-needles can increase the absorption of UV light.

Robust path planning for flexible needle insertion using Markov decision processes.

Science.gov (United States)

Tan, Xiaoyu; Yu, Pengqian; Lim, Kah-Bin; Chui, Chee-Kong

2018-05-11

Flexible needle has the potential to accurately navigate to a treatment region in the least invasive manner. We propose a new planning method using Markov decision processes (MDPs) for flexible needle navigation that can perform robust path planning and steering under the circumstance of complex tissue-needle interactions. This method enhances the robustness of flexible needle steering from three different perspectives. First, the method considers the problem caused by soft tissue deformation. The method then resolves the common needle penetration failure caused by patterns of targets, while the last solution addresses the uncertainty issues in flexible needle motion due to complex and unpredictable tissue-needle interaction. Computer simulation and phantom experimental results show that the proposed method can perform robust planning and generate a secure control policy for flexible needle steering. Compared with a traditional method using MDPs, the proposed method achieves higher accuracy and probability of success in avoiding obstacles under complicated and uncertain tissue-needle interactions. Future work will involve experiment with biological tissue in vivo. The proposed robust path planning method can securely steer flexible needle within soft phantom tissues and achieve high adaptability in computer simulation.

Drilling electrode for real-time measurement of electrical impedance in bone tissues.

Science.gov (United States)

Dai, Yu; Xue, Yuan; Zhang, Jianxun

2014-03-01

In order to prevent possible damages to soft tissues, reliable monitoring methods are required to provide valuable information on the condition of the bone being cut. This paper describes the design of an electrical impedance sensing drill developed to estimate the relative position between the drill and the bone being drilled. The two-electrode method is applied to continuously measure the electrical impedance during a drill feeding movement: two copper wire brushes are used to conduct electricity in the rotating drill and then the drill is one electrode; a needle is inserted into the soft tissues adjacent to the bone being drilled and acts as another electrode. Considering that the recorded electrical impedance is correlated with the insertion depth of the drill, we theoretically calculate the electrode-tissue contact impedance and prove that the rate of impedance change varies considerably when the drill bit crosses the boundary between two different bone tissues. Therefore, the rate of impedance change is used to determine whether the tip of the drill is located in one of cortical bone, cancellous bone, and cortical bone near a boundary with soft tissue. In vitro experiments in porcine thoracic spines were performed to demonstrate the feasibility of the impedance sensing drill. The experimental results indicate that the drill, used with the proposed data-processing method, can provide accurate and reliable breakthrough detection in the bone-drilling process.

[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.

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

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....

Rooting of needle fascicles from western white pine seedlings

Science.gov (United States)

Ramond J. Hoff; Geral I. McDonald

1968-01-01

In one test, 45 out of 318 (14 percent) needle fascicles from 2-year-old seedlings of Pinus monticola Dougl. were rooted. Eight of the needle fascicles produced shoot growth. In another test, 392 out of 742 (53 percent) needle fascicles were rooted, but none of these produced shoot growth.

Smart surgical needle actuated by shape memory alloys for percutaneous procedures

Science.gov (United States)

Konh, Bardia

Background: Majority of cancer interventions today are performed percutaneously using needle-based procedures, i.e. through the skin and soft tissue. Insufficient accuracy using conventional surgical needles motivated researchers to provide actuation forces to the needle's body for compensating the possible errors of surgeons/physicians. Therefore, active needles were proposed recently where actuation forces provided by shape memory alloys (SMAs) are utilized to assist the maneuverability and accuracy of surgical needles. This work also aims to introduce a novel needle insertion simulation to predict the deflection of a bevel tip needle inside the tissue. Methods: In this work first, the actuation capability of a single SMA wire was studied. The complex response of SMAs was investigated via a MATLAB implementation of the Brinson model and verified via experimental tests. The material characteristics of SMAs were simulated by defining multilinear elastic isothermal stress-strain curves. Rigorous experiments with SMA wires were performed to determine the material properties as well as to show the capability of the code to predict a stabilized SMA transformation behavior with sufficient accuracy. The isothermal stress-strain curves of SMAs were simulated and defined as a material model for the Finite Element Analysis of the active needle. In the second part of this work, a three-dimensional finite element (FE) model of the active steerable needle was developed to demonstrate the feasibility of using SMA wires as actuators to bend the surgical needle. In the FE model, birth and death method of defining boundary conditions, available in ANSYS, was used to achieve the pre-strain condition on SMA wire prior to actuation. This numerical model was validated with needle deflection experiments with developed prototypes of the active needle. The third part of this work describes the design optimization of the active using genetic algorithm aiming for its maximum flexibility

Needle Decompression of Tension Pneumothorax with Colorimetric Capnography.

Science.gov (United States)

Naik, Nimesh D; Hernandez, Matthew C; Anderson, Jeff R; Ross, Erika K; Zielinski, Martin D; Aho, Johnathon M

2017-11-01

The success of needle decompression for tension pneumothorax is variable, and there are no objective measures assessing effective decompression. Colorimetric capnography, which detects carbon dioxide present within the pleural space, may serve as a simple test to assess effective needle decompression. Three swine underwent traumatically induced tension pneumothorax (standard of care, n = 15; standard of care with needle capnography, n = 15). Needle thoracostomy was performed with an 8-cm angiocatheter. Similarly, decompression was performed with the addition of colorimetric capnography. Subjective operator assessment of decompression was recorded and compared with true decompression, using thoracoscopic visualization for both techniques. Areas under receiver operating curves were calculated and pairwise comparison was performed to assess statistical significance (P pneumothorax, that is, the absence of any pathologic/space-occupying lesion, in 100% of cases (10 of 10 attempts). Standard of care needle decompression was detected by operators in 9 of 15 attempts (60%) and was detected in 3 of 10 attempts when tension pneumothorax was not present (30%). True decompression, under direct visualization with thoracoscopy, occurred 15 of 15 times (100%) with capnography, and 12 of 15 times (80%) without capnography. Areas under receiver operating curves were 0.65 for standard of care and 1.0 for needle capnography (P = .002). Needle decompression with colorimetric capnography provides a rapid, effective, and highly accurate method for eliminating operator bias for tension pneumothorax decompression. This may be useful for the treatment of this life-threatening condition. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

The longitudinal distribution of elements in developing and aging scots pine needles

International Nuclear Information System (INIS)

Viksna, A.; Helmisaari, H.S.; Standzenieks, P.; Lindgren, E.S.

2001-01-01

Needle or leaf nutrient concentrations are commonly used for analysing tree nutritional status for e.g. estimating possible nutrient deficiencies or unbalances. The practise used e.g. in northern Europe is to sample needles during the dormant period from either the current or in some cases several needle age classes from a fixed position of a number of trees in a stand. The sampled needles are then dried and ground for nutrient analysis. The sampling aims to minimise the spatial and temporal variation in needle nutrient concentrations for estimating the availability of nutrients in soil through needle analysis. It is well known that the concentrations of different nutrients vary in needles with the phase of the annual physiological cycle (Fife and Nambiar 1982, 1984), needle age (Florence and Chuoung 1974, Madgwick et al. 1983) and sampling position (Helmisaari 1992). The samples analysed are usually bulk samples of a large number of needles, and the results are mean concentrations representing an age class in a stand. There is little information on how different needles vary in nutrient concentrations, and even less on how nutrient concentrations vary within individual needles. The import and export of elements to and from needles varies according to the developmental phase of needles, and is likely to affect the element concentrations in different parts of the needles. Accordingly, the elemental concentrations measured in different parts of the needles may give an insight into the transport pattern of an element and its potential mobility. Up to now, very few studies report needle element concentrations in different parts of the needles, e.g. tip, base and middle (Giertych et al. 1997), or in different parts of the leaf phloem (Eschrich et al. 1988). The aim of this study was to determine the distribution of different elements along the length of single Scots pine needles of different age and during different stages of needle physiological cycle. The scanning

Sugar export limits size of conifer needles

DEFF Research Database (Denmark)

Rademaker, Hanna; Zwieniecki, Maciej A.; Bohr, Tomas

2017-01-01

Plant leaf size varies by more than three orders of magnitude, from a few millimeters to over one meter. Conifer leaves, however, are relatively short and the majority of needles are no longer than 6 cm. The reason for the strong confinement of the trait-space is unknown. We show that sugars...... does not contribute to sugar flow. Remarkably, we find that the size of the active part does not scale with needle length. We predict a single maximum needle size of 5 cm, in accord with data from 519 conifer species. This could help rationalize the recent observation that conifers have significantly...

CUDA accelerated simulation of needle insertions in deformable tissue

International Nuclear Information System (INIS)

Patriciu, Alexandru

2012-01-01

This paper presents a stiff needle-deformable tissue interaction model. The model uses a mesh-less discretization of continuum; avoiding thus the expensive remeshing required by the finite element models. The proposed model can accommodate both linear and nonlinear material characteristics. The needle-deformable tissue interaction is modeled through fundamental boundaries. The forces applied by the needle on the tissue are divided in tangent forces and constraint forces. The constraint forces are adaptively computed such that the material is properly constrained by the needle. The implementation is accelerated using NVidia CUDA. We present detailed analysis of the execution timing in both serial and parallel case. The proposed needle insertion model was integrated in a custom software that loads DICOM images, generate the deformable model, and can simulate different insertion strategies.

Precision grid and hand motion for accurate needle insertion in brachytherapy

International Nuclear Information System (INIS)

McGill, Carl S.; Schwartz, Jonathon A.; Moore, Jason Z.; McLaughlin, Patrick W.; Shih, Albert J.

2011-01-01

Purpose: In prostate brachytherapy, a grid is used to guide a needle tip toward a preplanned location within the tissue. During insertion, the needle deflects en route resulting in target misplacement. In this paper, 18-gauge needle insertion experiments into phantom were performed to test effects of three parameters, which include the clearance between the grid hole and needle, the thickness of the grid, and the needle insertion speed. Measurement apparatus that consisted of two datum surfaces and digital depth gauge was developed to quantify needle deflections. Methods: The gauge repeatability and reproducibility (GR and R) test was performed on the measurement apparatus, and it proved to be capable of measuring a 2 mm tolerance from the target. Replicated experiments were performed on a 2 3 factorial design (three parameters at two levels) and analysis included averages and standard deviation along with an analysis of variance (ANOVA) to find significant single and two-way interaction factors. Results: Results showed that grid with tight clearance hole and slow needle speed increased precision and accuracy of needle insertion. The tight grid was vital to enhance precision and accuracy of needle insertion for both slow and fast insertion speed; additionally, at slow speed the tight, thick grid improved needle precision and accuracy. Conclusions: In summary, the tight grid is important, regardless of speed. The grid design, which shows the capability to reduce the needle deflection in brachytherapy procedures, can potentially be implemented in the brachytherapy procedure.

Inserting needles into the body: a meta-analysis of brain activity associated with acupuncture needle stimulation.

Science.gov (United States)

Chae, Younbyoung; Chang, Dong-Seon; Lee, Soon-Ho; Jung, Won-Mo; Lee, In-Seon; Jackson, Stephen; Kong, Jian; Lee, Hyangsook; Park, Hi-Joon; Lee, Hyejung; Wallraven, Christian

2013-03-01

Acupuncture is a therapeutic treatment that is defined as the insertion of needles into the body at specific points (ie, acupoints). Advances in functional neuroimaging have made it possible to study brain responses to acupuncture; however, previous studies have mainly concentrated on acupoint specificity. We wanted to focus on the functional brain responses that occur because of needle insertion into the body. An activation likelihood estimation meta-analysis was carried out to investigate common characteristics of brain responses to acupuncture needle stimulation compared to tactile stimulation. A total of 28 functional magnetic resonance imaging studies, which consisted of 51 acupuncture and 10 tactile stimulation experiments, were selected for the meta-analysis. Following acupuncture needle stimulation, activation in the sensorimotor cortical network, including the insula, thalamus, anterior cingulate cortex, and primary and secondary somatosensory cortices, and deactivation in the limbic-paralimbic neocortical network, including the medial prefrontal cortex, caudate, amygdala, posterior cingulate cortex, and parahippocampus, were detected and assessed. Following control tactile stimulation, weaker patterns of brain responses were detected in areas similar to those stated above. The activation and deactivation patterns following acupuncture stimulation suggest that the hemodynamic responses in the brain simultaneously reflect the sensory, cognitive, and affective dimensions of pain. This article facilitates a better understanding of acupuncture needle stimulation and its effects on specific activity changes in different brain regions as well as its relationship to the multiple dimensions of pain. Future studies can build on this meta-analysis and will help to elucidate the clinically relevant therapeutic effects of acupuncture. Copyright © 2013 American Pain Society. All rights reserved.

Does the effect of acupuncture depend on needling sensation and manipulation?

Science.gov (United States)

Choi, Yu-Jin; Lee, Jae-Eun; Moon, Won-Kyung; Cho, Seung-Hun

2013-06-01

Acupuncture sensation and manipulation have been considered to be an important component of acupuncture in traditional Asian medicine. However, there has been limited research as to whether acupuncture sensation is associated with therapeutic benefit. This study investigated the relationship between acupuncture sensation and analgesic effect according to acupuncture manipulation. Fifty-three healthy volunteers received three different forms of acupuncture in a single-blinded crossover design: superficial needling (0.3 cm), deep needling (2 cm) and needling with bi-directional rotation. The effects of acupuncture were evaluated by using the pressure pain threshold. Acupuncture sensation measurement was done in two ways. Both total acupuncture sensation and increase of the pressure pain threshold were maximum in needling with rotation, followed by deep needling and superficial needling. Repeated-measure analysis of variance (ANOVA) analysis was carried out to assess whether there was a significant difference; both showed significant difference (p = 0.000, 0.003). A paired sample t-test was carried out, which revealed that needling with rotation showed significant difference from both superficial needling and deep needling. Further, the correlation between the total acupuncture sensation and changes in pressure pain threshold were calculated using Pearson correlation; there was a significant correlation (p = 0.002, p = 0.013). Acupuncture sensation and pressure pain threshold increase according to the depth and rotation of acupuncture. Especially, both display significant increase with needle rotation. Further, there is a significant correlation between acupuncture needling sensation and increase in pressure pain threshold. It seems that needle rotation and acupuncture sensation play an important role in verifying the effect of acupuncture. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fine needle aspiration cytology of cervicofacial actinomycosis

Directory of Open Access Journals (Sweden)

Venkatesh Kusuma

2008-01-01

Full Text Available Actinomycosis is a chronic infection caused by Actinomyces israelii, usually seen in immunocompromised patients or in the background of tissue injury. Cervicofacial actinomycosis presenting as a fixed jaw swelling in an elderly individual can mimic malignancy and pose a diagnostic dilemma. We report here a case of cervicofacial actinomycosis diagnosed by fine needle aspiration, along with a review of the relevant literature. A 60 year-old man presented with a gradually increasing 6 x 5 cm swelling in the left side of his jaw. The swelling was fixed, without any apparent sinus or abscess. Fine needle aspiration was diagnostic as it revealed colonies of actinomyces surrounded by polymorphs and chronic inflammatory cells. The histopathological study of the excised specimen confirmed the cytological findings. Fine needle aspiration is an effective tool in the diagnosis of actinomycosis although its documentation is rare. Difficulties in the management can be avoided by early diagnosis using the fine needle aspiration technique.

CT-guided spinal injection: initial experience with Sprotte tip needles

Energy Technology Data Exchange (ETDEWEB)

Pua, Uei [Tan Tock Seng Hospital, Department of Diagnostic Radiology, Singapore (Singapore)

2010-09-15

The purpose of this paper is to describe our initial experience and to illustrate the potential benefits of using small caliber (25 and 27 G), noncutting pencil point needles (Sprotte) with single puncture coaxial technique in CT-guided spinal intervention (CTSI). From January 2009 to June 2009, Sprotte needles with single puncture coaxial technique were used in a total of ten patients for selective nerve root block (SNRB), facet joint block, and pars block under CT fluoroscopy (total of 16 target structures). All procedures were performed without conscious sedation, and visual analog scale (VAS) scores were recorded to determine pain related to needle placement. Total CT fluoroscopy time and out-of-plane needle deviation were obtained. Final needle position was documented by contrast injection for SNRBs and image capture for joint space cannulation. Sixteen out of the 16 structures were successfully targeted. No increase in VAS scores associated with needle placement was recorded, after infiltration of local anesthesia. Optimal peri-neurograms were obtained in all cases of SNRB, despite the side-hole opening in the Sprotte needles. Mean CT fluoroscopy time was 2 s (range 2-8 s per structure), and there was no case of out-of-plane needle deviation that required adjustment of the CT gantry. The use of small caliber Sprotte needles in CTSI is technically feasible and represents a potential refinement to current techniques in the management of chronic spinal pain. (orig.)

Evaluation of heat transfer in acupuncture needles: convection and conduction approaches.

Science.gov (United States)

Tzou, Chieh-Han John; Yang, Tzyy-Yih; Chung, Ya-Chien

2015-04-01

Originating in ancient China, acupuncture using needles has been developed for thousands of years and has received attention for its reported medical remedies, such as pain relief and chronic disease treatment. Heat transfer through the needles, which might have effects on the biomechanism of acupuncture, providing a stimulus and regulating homeostasis, has never been studied. This article analyzes the significance of heat transfer through needles via convection and conduction, approached by means of computational analysis. The needle is a cylindrical body, and an axis symmetrical steady-state heat-transfer model that viscosity and static pressure was not applied. This article evaluates heat transfer via acupuncture needles by using five metal materials: silver, copper, brass, iron, and stainless steel. A silver needle of the type extensively applied in acupuncture can dissipate more than seven times as much heat as a stainless steel needle of the same type. Heat transfer through such a needle is significant, compared to natural body-energy consumption over a range of ambient temperatures. The mechanism by which heat flows in or out of the body through the needles may be crucial in the remedial efficacy of acupuncture. Copyright © 2015. Published by Elsevier B.V.

Return Rates for Needle Exchange Programs: A Common Criticism Answered

Directory of Open Access Journals (Sweden)

Ksobiech Kate

2004-04-01

Full Text Available Abstract This study searched the available needle exchange program (NEP literature for return rate data. A total of 26 articles were found. The overall worldwide return rate was 90%, although this ranged from a low of 15% to a high of 112%. U.S. NEP return rates were gathered from only eight studies, indicating a clear need for more data, although U.S. return rates were comparable to those from NEPs outside of the U.S. One underlying assumption made by opponents of NEPs is that IDUs will not return needles to the distribution site, thereby potentially increasing the risk of health problems to the surrounding community from exposure to contaminated needles. This study's results suggest that NEPs are relatively successful in taking in used needles, although it is generally unclear where the needles were originally acquired, and if IDUs return their own needles, or are returning needles for a social network. Ways for AIDS Service Organizations to capitalize on these brief encounters with IDUs, as well as public policy implications of the findings, are discussed.

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.

An ultrasound-driven needle-insertion robot for percutaneous cholecystostomy

International Nuclear Information System (INIS)

Hong, J; Dohi, T; Hashizume, M; Konishi, K; Hata, N

2004-01-01

A real-time ultrasound-guided needle-insertion medical robot for percutaneous cholecystostomy has been developed. Image-guided interventions have become widely accepted because they are consistent with minimal invasiveness. However, organ or abnormality displacement due to involuntary patient motion may undesirably affect the intervention. The proposed instrument uses intraoperative images and modifies the needle path in real time by using a novel ultrasonic image segmentation technique. In phantom and volunteer experiments, the needle path updating time was 130 and 301 ms per cycle, respectively. In animal experiments, the needle could be placed accurately in the target

Spruce needles used as radioecological biotracers

International Nuclear Information System (INIS)

Seidel, C.; Gruber, V.; Baumgartner, A.

2009-01-01

In a two years project spruce needle samples of the Austrian Bioindicator Grid were analysed by gamma-ray spectrometry to investigate the spatial and temporal distribution of radionuclides in spruce needles of the last 25 years with the main focus on the radioactive contamination before and after the Chernobyl fallout 1986. More than 600 spruce needle samples at selected locations of the Bioindicator Grid were analysed for different natural and anthropogenic radionuclides: 137 Cs, 40 K, 210 Pb, 226 Ra, 228 Ra, 238 U. Additionally, soil samples were taken at selected sites to study the soil-to-plant transfer. This radioecological evaluation is an important part of an existing environmental surveillance programme in Upper Austria in order to gain basic information on the impact of environmental changes on the radioecological behaviour of spruce trees. (orig.)

A new robotic needle insertion method to minimise attendant prostate motion

International Nuclear Information System (INIS)

Lagerburg, Vera; Moerland, Marinus A.; Vulpen, Marco van; Lagendijk, Jan J.W.

2006-01-01

Background and purpose: The purpose of this study is to investigate the efficacy of a new needle insertion method (tapping instead of pushing) in reducing attendant tissue motion. This can be useful in applications where tissue motion due to needle insertion is problematic such as e.g. MRI-guided prostate brachytherapy and breast biopsies. In this study we will focus on prostate motion due to needle insertion. Material and methods: Prostate motion due to needle insertion was measured in 30 patients, who were transperineally implanted with fiducial gold markers for position verification in prostate intensity modulated radiotherapy. In total 32 needles were manually pushed into the prostate and 29 were tapped with a prototype robotic system. The prostate motion in the cranio-caudal direction was measured on the video record of the ultrasound images. Differences in prostate motion between the two needle insertion methods were analysed making use of SPSS. Results: The mean prostate motion was 5.6 mm (range 0.3-21.6) when the needle was pushed and 0.9 mm (range 0-2.0) when the needle was tapped into the prostate (p < 0.001). Conclusion: Prostate motion was significantly less when the needle was tapped into the prostate compared to when the needle was pushed. This result is important for the development of a tapping, MRI-guided, prostate implant robotic system

Spots on electrodes and images of a gap during pulsed discharges in an inhomogeneous electric field at elevated pressures of air, nitrogen and argon

International Nuclear Information System (INIS)

Shao, Tao; Yang, Wenjin; Zhang, Cheng; Yan, Ping; Tarasenko, Victor F; Beloplotov, Dmitry V; Lomaev, Mikhail I; Sorokin, Dmitry A

2014-01-01

Pulsed discharge in a nonuniform electric field accompanied by the appearance of bright spots due to explosive electron emission on electrodes has been investigated. The experiments were carried out using three experimental setups, a voltage pulse duration at a matched load of 2 ns, 40 ns, and 130 ns, respectively. Data on the formation of electrode spots during diffuse discharges in tube-plate or needle-plate gap configurations filled with gases at elevated pressures (air, nitrogen and argon) were obtained. It was found that in the air and other gases, bright spots arise on the flat electrode, and on the negative polarity of the electrode with a small radius of curvature, during the direction change of the current through the gap and the increase of the voltage pulse duration. It was shown that at the positive polarity of the electrode with a small radius of curvature, bright spots on the flat electrode arise due to the participation of the dynamic displacement current in the gap conductance. (paper)

In-plane ultrasonic needle tracking using a fiber-optic hydrophone

Energy Technology Data Exchange (ETDEWEB)

Xia, Wenfeng, E-mail: wenfeng.xia@ucl.ac.uk; Desjardins, Adrien E. [Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT (United Kingdom); Mari, Jean Martial [Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom and GePaSud, University of French Polynesia, Faa’a 98702, French Polynesia (France); West, Simeon J. [Department of Anaesthesia, University College Hospital, Main Theatres, Maple Bridge Link Corridor, Podium 3, 235 Euston Road, London NW1 2BU (United Kingdom); Ginsberg, Yuval; David, Anna L. [Institute for Women’s Health, University College London, 86-96 Chenies Mews, London WC1E 6HX (United Kingdom); Ourselin, Sebastien [Center for Medical Imaging Computing, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2015-10-15

Purpose: Accurate and efficient guidance of needles to procedural targets is critically important during percutaneous interventional procedures. Ultrasound imaging is widely used for real-time image guidance in a variety of clinical contexts, but with this modality, uncertainties about the location of the needle tip within the image plane lead to significant complications. Whilst several methods have been proposed to improve the visibility of the needle, achieving accuracy and compatibility with current clinical practice is an ongoing challenge. In this paper, the authors present a method for directly visualizing the needle tip using an integrated fiber-optic ultrasound receiver in conjunction with the imaging probe used to acquire B-mode ultrasound images. Methods: Needle visualization and ultrasound imaging were performed with a clinical ultrasound imaging system. A miniature fiber-optic ultrasound hydrophone was integrated into a 20 gauge injection needle tip to receive transmissions from individual transducer elements of the ultrasound imaging probe. The received signals were reconstructed to create an image of the needle tip. Ultrasound B-mode imaging was interleaved with needle tip imaging. A first set of measurements was acquired in water and tissue ex vivo with a wide range of insertion angles (15°–68°) to study the accuracy and sensitivity of the tracking method. A second set was acquired in an in vivo swine model, with needle insertions to the brachial plexus. A third set was acquired in an in vivo ovine model for fetal interventions, with insertions to different locations within the uterine cavity. Two linear ultrasound imaging probes were used: a 14–5 MHz probe for the first and second sets, and a 9–4 MHz probe for the third. Results: During insertions in tissue ex vivo and in vivo, the imaged needle tip had submillimeter axial and lateral dimensions. The signal-to-noise (SNR) of the needle tip was found to depend on the insertion angle. With

[King Injo's disease and burnt needle therapy].

Science.gov (United States)

Kim, In-Sook

2004-12-01

This paper investigates an interrelationship between burnt needle therapy and King Injo's disease. From 1633 (Year 11 in King Injo's reign) to May 5, 1649 (Year 27 in King Injo's reign), right before his death, King Injo was treated with burnt needles by Yi Hyeongik, an acupuncturist when the king had health problems. This study arises from two questions: why was King Injo often treated with burnt needles? and what effect did burnt needles have?Burnt needle therapy is a combined form of acupuncture and moxibustion. Yi Hyeongik was famous for eradicating pathogenic factors. He was appointed as a doctor in the Royal Hospital. The medical definition for pathogenic factors is that they are disease-causing factors. Understanding the pathogenic factor for King Injo's disease could make it possible to find the interrelationship between burnt needles and the king's disease. In the Joseon ear, the prevalent belief about diseases was that diseases could be caused by homeopathic magic. Some people thought homeopathic magic caused King Injo's disease. The actual reasons for King Injo's disease were the participation in the excessive rites of Queen Mother Inmok's funeral and the constant oppression from the Ching Dynasty after disgraceful defeat in the war. When King Injo started to be sick, homeopathic magic cases were found in the royal palace. The king's incurable disease was believed to have happened as a result of homeopathic magic. King Injo's suspicion toward Princess Jeongmyeong derived from her mother, Queen Mother Inmok. Moral justification for King Injo's coup was Gwanghaegun or Prince Gwanghae's immoral conduct toward Queen Mothe Inmok. After he was installed, King Injo obeyed the Queen Mother and showed her every attention. Meanwhile, he treated Princess Jeongmyeong with respect, maximized the moral justification for the coup, and solidified the royal authority. However, constant rebellions and treasons threatened King Injo. The king suspected that Queen Mother

Fine Needle Aspiration Biopsy in a Rural Family Practice

African Journals Online (AJOL)

ultrasound scan. A 21-gauge 1½-inch or 23-gauge 1¼-inch needle, attached to a 10-mL disposable plastic syringe, was used for FNAB of superficial masses. For percutaneous FNAB of deep-seated organs and masses, a 23 gauge 1¼-inch needle or 3½-inch spinal needle was used. The aspirate was spread on slides and ...

A comparative study of electrochemical performance of graphene sheets, expanded graphite and natural graphite as anode materials for lithium-ion batteries

International Nuclear Information System (INIS)

Bai, Li-Zhong; Zhao, Dong-Lin; Zhang, Tai-Ming; Xie, Wei-Gang; Zhang, Ji-Ming; Shen, Zeng-Min

2013-01-01

Highlights: • Graphene sheets (GSs), expanded graphite (EG) and natural graphite (NG) were comparatively investigated as anode materials for lithium-ion batteries. • The reversible capacity of GS electrode was almost twice that of EG electrode and three times that of NG electrode. • The first-cycle coulombic efficiency and capacity retention of NG were much bigger than those of GSs and EG. • GS and EG electrodes exhibited higher electrochemical activity and more favorable kinetic properties. -- Abstract: Three kinds of carbon materials, i.e., graphene sheets (GSs), expanded graphite (EG) and natural graphite (NG) were comparatively investigated as anode materials for lithium-ion batteries via scanning electron microscope, high-resolution transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy and a variety of electrochemical testing techniques. The test results showed that the reversible capacities of GS electrode were 1130 and 636 mA h g −1 at the current densities of 0.2 and 1 mA cm −2 , respectively, which were almost twice those of EG electrode and three times those of NG electrode. The first-cycle coulombic efficiency and capacity retention of NG were much bigger than those of GSs and EG. The notable capacity fading observed in GSs and EG may be ascribed to the disorder-induced structure instability. The larger voltage hysteresis in GS and EG electrodes was not only related to the surface functional groups, but also to the active defects in GSs and EG, which results in greater hindrance and higher overvoltage during lithium extraction from electrode. The kinetics properties of GSs, EG and NG electrodes were compared by AC impedance measurements. GS and EG electrodes exhibited higher electrochemical activity and more favorable kinetic properties during charge and discharge process

Sonographically guided fine-needle biopsy of thyroid nodules: the effects of nodule characteristics, sampling technique, and needle size on the adequacy of cytological material

International Nuclear Information System (INIS)

Degirmenci, B.; Haktanir, A.; Albayrak, R.; Acar, M.; Sahin, D.A.; Sahin, O.; Yucel, A.; Caliskan, G.

2007-01-01

Aim: To evaluate the effects of sonographic characteristics of thyroid nodules, the diameter of needle used for sampling, and sampling technique on obtaining sufficient cytological material (SCM). Materials and methods: We performed sonography-guided fine-needle biopsy (FNB) in 232 solid thyroid nodules. Size-, echogenicity, vascularity, and localization of all nodules were evaluated by Doppler sonography before the biopsy. Needles of size 20, 22, and 24 G were used for biopsy. The biopsy specimen was acquired using two different methods after localisation. In first method, the needle tip was advanced into the nodule in various positions using a to-and-fro motion whilst in the nodule, along with concurrent aspiration. In the second method, the needle was advanced vigorously using a to-and-fro motion within the nodule whilst being rotated on its axis (capillary-action technique). Results: The mean nodule size was 2.1 ± 1.3 cm (range 0.4-7.2 cm). SCM was acquired from 154 (66.4%) nodules by sonography-guided FNB. In 78 (33.6%) nodules, SCM could not be collected. There was no significant difference between nodules with different echogenicity and vascularity for SCM. Regarding the needle size, the lowest rate of SCM was obtained using 20 G needles (56.6%) and the highest rate of adequate material was obtained using 24 G needles (82.5%; p = 0.001). The SCM rate was 76.9% with the capillary-action technique versus 49.4% with the aspiration technique (p < 0.001). Conclusion: Selecting finer needles (24-25 G) for sonography-guided FNB of thyroid nodules and using the capillary-action technique decreased the rate of inadequate material in cytological examination

[Research progress of needles with knife-edge for carotid cardiac syndrome].

Science.gov (United States)

Tan, Lingqiong; Zhao, Yanling

2015-04-01

According to topographic anatomy, pathogenesis and by retrieving, summarizing and analyzing literature regarding needle-knife and needles with knife-edge for carotid cardiac syndrome, it is found out that clinical misdiagnosis rate of carotid cardiac syndrome is considerably high. Needle-knife and needles with knife-edge could significantly improve the clinical symptoms of carotid cardiac syndrome, showing characteristic and advantage in treatment, but it is deficient in technique standard and efficacy criteria that should be united and authoritative. Researches regarding pathogenesis of carotid cardiac syndrome are not systematic. Clinical observation regarding long-term efficacy and relapse of needle-knife and needles with knife-edge treatment is rare. It is believed that the awareness on carotid cardiac syndrome should be increased to reduce misdiagnosis; scientific and standardized technique standard and efficacy criteria should be established; systematic and comprehensive researches regarding mechanism of needle-knife and needles with knife-edge for carotid cardiac syndrome should be launched; besides, clinical discussion regarding its long-term efficacy should start to provide a better clinical guideline.

Improving needle tip identification during ultrasound-guided procedures in anaesthetic practice.

Science.gov (United States)

Scholten, H J; Pourtaherian, A; Mihajlovic, N; Korsten, H H M; A Bouwman, R

2017-07-01

Ultrasound guidance is becoming standard practice for needle-based interventions in anaesthetic practice, such as vascular access and peripheral nerve blocks. However, difficulties in aligning the needle and the transducer can lead to incorrect identification of the needle tip, possibly damaging structures not visible on the ultrasound screen. Additional techniques specifically developed to aid alignment of needle and probe or identification of the needle tip are now available. In this scoping review, advantages and limitations of the following categories of those solutions are presented: needle guides; alterations to needle or needle tip; three- and four-dimensional ultrasound; magnetism, electromagnetic or GPS systems; optical tracking; augmented (virtual) reality; robotic assistance; and automated (computerised) needle detection. Most evidence originates from phantom studies, case reports and series, with few randomised clinical trials. Improved first-pass success and reduced performance time are the most frequently cited benefits, whereas the need for additional and often expensive hardware is the greatest limitation to widespread adoption. Novice ultrasound users seem to benefit most and great potential lies in education. Future research should focus on reporting relevant clinical parameters to learn which technique will benefit patients most in terms of success and safety. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

Risk of needle stick injuries in health care workers: bad habits (recapping needles) last long.

Science.gov (United States)

Rogowska-Szadkowska, Dorota; Stanisławowicz, Małgorzata; Chlabicz, Sławomir

2010-01-01

In order to assess the nurses' knowledge concerning the risk of hepatitis B and C viruses or human immunodeficiency virus infection while performing their professional duties, an anonymous questionnaire developed by the authors was distributed in 2008. Surprisingly 64% respondents occasionally recapping needles after injections, although they know the procedures which are obligatory at the ward. The first step in preventing percutaneous injuries should focus on efforts to eliminate the practice of recapping needles, though education and convenient placement of puncture-resistant containers for the disposal of used sharps.

[Special penetration needling for refractory peripheral facial paralysis].

Science.gov (United States)

Cao, Rongjuan; Qiu, Xiaohu; Xie, Xiaokun

2018-03-12

To observe the clinical effect difference between special penetration needling and conventional penetration needling for the refractory peripheral facial paralysis. A total of 97 patients with intractable facial paralysis were randomized into an observation group (49 cases and 2 dropping) and a control group (48 cases and 4 dropping). In the observation group, special penetration needling at an angle about 45° between the penetration needle and paralysis muscle bundle was used, Yangbai (GB 14) through Touwei (ST 8), Yangbai (GB 14) through Shangxing (GV 23), Sizhukong (TE 23) through Yuyao (EX-HN 4), Qianzhen (Extra) through Yingxiang (LI 20), mutual penetration between Yingxiang (LI 20) and Jiache (ST 6). Conventional penetration needling was applied in the control group, Yangbai (GB 14) through Yuyao (EX-HN 4), Cuanzhu (BL 2) through Yuyao (EX-HN 4), mutual penetration between Dicang (ST 4) and Jiache (ST 6), Qianzheng (Extra) through Dicang (ST 4), Sibai (ST 2) through Yingxiang (LI 20). Three groups of electroacupuncture (discontinuous wave, 1 Hz) with tolerance were connected respectively in the two groups, Yangbai (GB 14) and Sizhukong (TE 23), Yangbai (GB 14) and Qianzheng (Extra), Yingxiang (LI 20) and Jiache (ST 6) in the observation group, Yangbai (GB 14) and Cuanzhu (BL 2), Dicang (ST 4) and Jiache (ST 6), Qianzheng (Extra) and Sibai (ST 2) in the control group. TDP was applied in the two groups at the affected Yifeng (TE 17), Jiache (ST 6) and Qianzheng (Extra), which were around the ear. Perpendicular insertion was used at Yifeng (TE 17) at the affected side and Hegu (LI 4) at the healthy side and bilateral Zusanli (ST 36). The needles were retained for 30 min. The treatment was given for 3 courses, once a day and 10 days as a course, 5 days at the interval. House-Brackmann (H-B) facial nerve grading score was recorded before and after treatment. The clinical effects were compared. The H-B scores after treatment in the two groups were higher than

Drug-related deaths and the sales of needles through pharmacies.

Science.gov (United States)

Davidson, Peter J; Martinez, Alexis; Lutnick, Alexandra; Kral, Alex H; Bluthenthal, Ricky N

2015-02-01

Providing needles to people who inject drugs is a well-proven public health response to the transmission of HIV and other blood borne viruses. Despite over a quarter of a century of research, new concerns about potential unintended negative consequences of needle distribution continue to emerge. Specifically, a claim was recently made that the introduction of pharmacy sales of needles was followed by an increase in overdoses in pharmacy parking lots. If true, this would have serious implications for the design of needle access programs, particularly those involving pharmacy sales of needles. We examine spatial relationships between drug-related deaths and pharmacies in Los Angeles County (population 9.8 million) before and after the 2007 enactment of a California law allowing pharmacy sales of needles without a prescription. Seven thousand and forty-nine drugs related deaths occurred in Los Angeles county from 2000 to 2009 inclusive. Four thousand two hundred and seventy-five of these deaths could be geocoded, and were found to be clustered at the census tract level. We used three methods to examine spatial relationships between overdose death locations and pharmacy locations for two years on either side of the enactment of the pharmacy sales law, and found no statistically significant changes. Among the 711 geocodable deaths occurring in the two years following the change in law, no death was found to occur within 50m of a pharmacy which sold needles. These results are consistent with prior studies which suggest pharmacy sales of needles improve access to needles without causing increased harms to the surrounding community. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Structures and electrochemical performances of pyrolized carbons from graphite oxides for electric double-layer capacitor

Science.gov (United States)

Kim, Ick-Jun; Yang, Sunhye; Jeon, Min-Je; Moon, Seong-In; Kim, Hyun-Soo; Lee, Yoon-Pyo; An, Kye-Hyeok; Lee, Young-Hee

The structural features and the electrochemical performances of pyrolized needle cokes from oxidized cokes are examined and compared with those of KOH-activated needle coke. The structure of needle coke is changed to a single phase of graphite oxide after oxidation treatment with an acidic solution having an NaClO 3/needle coke composition ratio of above 7.5, and the inter-layer distance of the oxidized needle coke is expanded to 6.9 Å with increasing oxygen content. After heating at 200 °C, the oxidized needle coke is reduced to a graphite structure with an inter-layer distance of 3.6 Å. By contrast, a change in the inter-layer distance in KOH-activated needle coke is not observed. An intercalation of pyrolized needle coke, observed on first charge, occurs at 1.0 V. This value is lower than that of KOH-activation needle coke. A capacitor using pyrolized needle coke exhibits a lower internal resistance of 0.57 Ω in 1 kHz, and a larger capacitance per weight and volume of 30.3 F g -1 and 26.9 F ml -1, in the two-electrode system over the potential range 0-2.5 V compared with those of a capacitor using KOH-activation of needle coke. This better electrochemical performance is attributed to a distorted graphene layer structure derived from the process of the inter-layer expansion and shrinkage.

Root canal debris removal using different irrigating needles: An SEM study

Directory of Open Access Journals (Sweden)

Sheetal Ghivari

2011-01-01

Full Text Available Aim: This study was carried out to compare the efficacy of three irrigating needle designs in removal of debris from different parts of the root canal. Materials and Methods: Thirty human maxillary canines were prepared using HERO Shaper rotary system and irrigated with 1 ml of 5.25% sodium hypochlorite (NaOCl after each instrument change. Three 25-gauge irrigation needle designs - brush-covered Navi Tip FX (Group I, side-vented needle RC Twents (Group II and single-beveled (Group III irrigating needles - were tested for their efficiency in debris removal in three different parts of the root canal (n=10 canals per group. Following instrumentation, the roots were vertically sectioned and divided into coronal, middle and apical thirds for observation under scanning electron microscope (×200 magnification. Debris on the canal wall was evaluated by using a four-scale scoring system described by Paque and his co-workers. Results: The canals irrigated with brush-covered needle Navi Tip FX (Group I showed lower average debris score, indicating greater removal of debris in coronal third as compared to middle and apical thirds, whereas the canals irrigated with side-vented needle (Group II and single-beveled needle (Group III exhibited lower average score in the middle third than coronal and apical thirds. All the three needle designs exhibited higher debris score in apical third of the root canal. Tukey multiple comparisons test was applied at a significance level of P>0.05. A statistically significant difference (P<0.05 was observed in the debris removal in the coronal and middle thirds of root canals irrigated with brush-covered Navi Tip FX (Group I and side-vented (Group II needles, respectively, when compared with other needle design groups. Conclusion: Within the limitations of this study, it can be concluded that all the needle designs tested were effective in certain regions of the root canal with apical third uncleaned. Side-vented needle by

A climate response function explaining most of the variation in the forest floor needle mass and the needle decomposition in pine forests across Europe

DEFF Research Database (Denmark)

Kurz-Besson, C.; Coûteaux, M.M.; Berg, Bjørn

2006-01-01

The forest floor needle mass and the decomposition rates of pine needle litter in a European climate transect were studied in order to estimate the impact of climate change on forest soil carbon sequestration. Eight pine forests preserved from fire were selected along a climatic latitudinal...... gradient from 40° to 60° N, from Spain and Portugal to Sweden. The forest floor (Oi and Oe layers) was sorted into five categories of increasing decomposition level according to morphological criteria. The needle mass loss in each category was determined using a linear mass density method. The needle...... and a recalcitrant one. NF was correlated with actual evapotranspiration (AET) whereas the decomposition parameters (decomposition rate of the decomposable fraction, first year mass loss, forest floor needle mass, age of the most-decomposed category) were related to a combined response function to climate (CRF...

Characterization of surfactant/hydrotalcite-like clay/glassy carbon modified electrodes: Oxidation of phenol

International Nuclear Information System (INIS)

Hernandez, Maria; Fernandez, Lenys; Borras, Carlos; Mostany, Jorge; Carrero, Hermes

2007-01-01

The characteristics of hydrotalcite (HT)-like clay films containing ionic and nonionic surfactants and their ability to oxidize phenol have been examined. The HT clay (Co/Al-NO 3 ) was synthesized by coprecipitation techniques and then modified with surfactants such as sodium dodecylbenzenesulfonate (SDBS), octylphenoxypolyethoxyethanol (TX100) or cetylpyridinium bromide (CPB). X-ray diffraction analysis revealed that the interlayer basal spacing varied depending on the type of surfactant retained by the HT. The presence of SDBS and CPB expanded the HT interlayer, which in the presence of TX100 did not show an appreciable change. Phenol oxidation is favored at surfactant-HT-GC modified electrodes, after a preconcentration time, compared to phenol oxidation at HT-GC or GC electrodes. Surfactant-HT-GC modified electrodes display good stability in continuous electrochemical phenol oxidation. At pH values between 6 and 10.8, both SDBS-HT-GC and TX100-HT-GC modified electrodes seem to be promising electrodes for the detection of phenol in water; while the CPB-HT-GC modified electrode should be affected by the inorganic anions

[Meta-analysis of needle-knife treatment on cervical spondylosis].

Science.gov (United States)

Kan, Li-Li; Wang, Hai-Dong; Liu, An-Guo

2013-11-01

To assess the efficacy of cervical spondylosis by needle-knife treatment according to the correlated literature of RCT,to compare advantages of needle-knife treatment. Randomized Controlled Trials about needle-knife treatment of cervical spondylosis were indexed from Chinese HowNet (CNKI) and Wanfang (WF) from 2000 to 2012, then were analyzed the efficacy by Review Manager 5.1 software. A total of 13 RCT literatures and 1 419 patients were included. The methods of included studies were poor in quality evaluation because of large sample and multi-center RCT studies was lacked, randomization method was not accurate enough, diagnostic criteria and efficacy evaluation were various, only four studies described long-term efficacy, most of the literature didn't describe the adverse event and fall off,all studies did not use the blind method. The Meta analysis outcome showed overall efficiency of needle-knife therapy was better than acupuncture and traction. Needle-knife therapy compared with Acupuncture, the total RR = 0.19, 95% confidence interval was (0.15, 0.24), P knife therapy is higher;compared with traction therapy, although,needle-knife therapy has a high overall effectiveness, but because of the loss of total sample size, the outcome RCT researches to confirm.

Dry needling in lateral epicondylitis: a prospective controlled study.

Science.gov (United States)

Uygur, Esat; Aktaş, Birol; Özkut, Afşar; Erinç, Samet; Yilmazoglu, Emime Gül

2017-11-01

Lateral epicondylitis (LE), a common disease, especially in middle age, causes decreased productivity and economic losses. The first-line treatment for LE is conservative and consists of topical and oral anti-inflammatory drugs, ice application, and brace use. If the first-line treatment fails, second-line treatment modalities, which are generally invasive, are offered. Second-line therapeutic regimens include saline, corticosteroid, or platelet-rich plasma injections. Dry needling is relatively new. We hypothesized that dry needling would be at least as effective as first-line treatment for LE. We compared the outcomes of first-line treatment and dry needling. The study allocated 110 patients into groups using online randomization software. After completing the Patient-rated Tennis Elbow Evaluation (PRTEE), patients in group I received dry needling, whereas those in group II received first-line treatment, consisting of ibuprofen 100 mg twice a day and a proximal forearm brace. The patients were evaluated after three weeks and six months. The study ultimately analyzed 92 patients. Although both treatment methods were effective at three weeks, dry needling was significantly more effective than the first-line treatment at six months. Because of the low complication rate, dry needling is a safe method, and it might be an effective treatment option for LE.

King Injo's Disease and Burnt Needle Therapy

Directory of Open Access Journals (Sweden)

KIM In-Sook

2004-12-01

Full Text Available This paper investigates an interrelationship between burnt needle therapy(번침 and King Injo'sdisease. From 1633 (Year 11 in King Injo's reign to May 5, 1649 (Year 27 King in Injo's reign, right before his death, King Injo(인조 was treated with burnt needles by Yi Hyeongik(이형익, an acupuncturist when the king had health problems. This study arises from two questions: why was King Injo often treated with burnt needles? and what effect did burnt needles have? Burnt needle therapy is a combined form of acupuncture and moxibustion. Yi Hyeongik was famous for eradicating pathogenic factors. He was appointed as a doctor in the Royal Hospital. The medical definition for pathogenic factors is that they are disease-causing factors. Understanding the pathogenic factor for King Injo's disease could make it possible to find the interrelationship between burnt needles and the king's disease. In the Joseon era, the prevalent belief about diseases was that diseases could be caused by homeopathic magic. Some people thought homeopathic magic caused King Injo's disease.　 The actual reasons for King Injo's disease were the participation in the excessive rites of Queen Mother Inmok's funeral and the constant oppression from the Ching Dynasty after disgraceful defeat in the war. When King Injo started to be sick, homeopathic magic cases were found in the royal palace. The king's incurable disease was believed to have happened as a result of homeopathic magic. King Injo's suspicion toward Princess Jeongmyeong(정명공주 derived from her mother, Queen Mother Inmok(인목대비. Moral justification for King Injo's coup was Gwanghaegun(광해군 or Prince Gwanghae's immoral conduct toward Queen Mother Inmok. After he was installed, King Injo obeyed the Queen Mother and showed her every attention. Meanwhile, he treated Princess Jeongmyeong with respect, maximized the moral justification for the coup, and solidified the royal authority. However, constant

Are needle-free injections a useful alternative for growth hormone therapy in children? Safety and pharmacokinetics of growth hormone delivered by a new needle-free injection device compared to a fine gauge needle.

NARCIS (Netherlands)

Dorr, H.G.; Zabransky, S.; Keller, E.; Otten, B.J.; Partsch, C.J.; Nyman, L.; Gillespie, B.K.; Lester, N.R.; Wilson, A.M.; Hyren, C.; Kuijck, M.A. van; Schuld, P.; Schoenfeld, S.L.

2003-01-01

The clinical safety, use and pharmacokinetics of a new needle-free device for delivery of growth hormone (GH) were compared with those of conventional needle injection devices. In an open-label, randomized, 4-period crossover study, 18 healthy adults received single subcutaneous injections of

Electrode-electrolyte interface model of tripolar concentric ring electrode and electrode paste.

Science.gov (United States)

Nasrollaholhosseini, Seyed Hadi; Steele, Preston; Besio, Walter G

2016-08-01

Electrodes are used to transform ionic currents to electrical currents in biological systems. Modeling the electrode-electrolyte interface could help to optimize the performance of the electrode interface to achieve higher signal to noise ratios. There are previous reports of accurate models for single-element biomedical electrodes. In this paper we develop a model for the electrode-electrolyte interface for tripolar concentric ring electrodes (TCRE) that are used to record brain signals.

Fine-needle versus core-needle biopsy – which one to choose in preoperative assessment of focal lesions in the breasts? Literature review

Directory of Open Access Journals (Sweden)

Ewa Łukasiewicz

2017-12-01

Full Text Available Aim: The aim of the study was to review two techniques that can be used to verify focal lesions in the breasts: fine-needle aspiration biopsy and core-needle biopsy. Material and methods: Fifty-five articles (original papers and reviews, half of them published within the past 5 years, were included in the analysis. The authors also took their own experience into account. Results: Pre-operative assessment of focal lesions in the breasts is crucial in the planning of further therapeutic management. The role of fine-needle aspiration biopsy has been reduced lately due to its low sensitivity and specificity as well as a high rate of non-diagnostic, suspicious and false negative results. This method does not enable one to differentiate between in situ and invasive disease. Currently, fine-needle biopsy is recommended for cystic lesions, suspected of being recurrences in the chest wall, and lymph node metastases. Core-needle biopsy is the basic diagnostic method of breast lesions. According to the recommendations of the Polish Ultrasound Society and American College of Radiology, BIRADS 4 and 5 lesions should be evaluated histopathologically. Core-needle biopsy makes it possible to establish a final diagnosis more frequently than fine-needle biopsy, both in the case of benign and malignant lesions. It delivers more information about the nature of a tumor (mutation of HER-2, estrogen and progesterone receptors and Ki-67 index. Its limitations include: underestimation of invasion and failure to recognize the components of ductal carcinoma in situ in papillary and atypical lesions. Single fine-needle aspiration biopsy is inexpensive, but when considering the cost of further diagnosis due to non-diagnostic, suspicious and atypical results, this method generates high additional costs. Conclusions: Microscopic verification of focal breast lesions is crucial for further therapeutic decisions. It has been proven that histopathological verification is more

Modified microdissection electrocautery needle

OpenAIRE

Singh, Virendra; Kumar, Pramod

2014-01-01

Electrocautery is routinely used in surgical procedures. The commercially available microdissection electrocautery needles are costly. To overcome this disadvantage, we have modified monopolar electrocautery tip to function as well as commercially available systems.

Measurement of tritium in tissue free water of pine needles

International Nuclear Information System (INIS)

Zheng Xiaomin; Wu Zongmei

1993-01-01

Tissue Free Water (TFW) of pine needles is separated out through azeotropic distillation of pine needles and toluene. Recovery ratio of TFW is 90%. Tritium activity in the needles is 1.8 Bq/L(H 2 O), which is of the same level with tritiated water vapour (HTO) in atmosphere during the corresponding period

Comparison of Histologic Core Portions Acquired from a Core Biopsy Needle and a Conventional Needle in Solid Mass Lesions: A Prospective Randomized Trial.

Science.gov (United States)

Lee, Ban Seok; Cho, Chang-Min; Jung, Min Kyu; Jang, Jung Sik; Bae, Han Ik

2017-07-15

The superiority of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) over EUS-guided fine needle aspiration (EUS-FNA) remains controversial. Given the lack of studies analyzing histologic specimens acquired from EUS-FNB or EUS-FNA, we compared the proportion of the histologic core obtained from both techniques. A total of 58 consecutive patients with solid mass lesions were enrolled and randomly assigned to the EUS-FNA or EUS-FNB groups. The opposite needle was used after the failure of core tissue acquisition using the initial needle with up to three passes. Using computerized analyses of the scanned histologic slide, the overall area and the area of the histologic core portion in specimens obtained by the two techniques were compared. No significant differences were identified between the two groups with respect to demographic and clinical characteristics. Fewer needle passes were required to obtain core specimens in the FNB group (pcore (11.8%±19.5% vs 8.0%±11.1%, p=0.376) or in the diagnostic accuracy (80.6% vs 81.5%, p=0.935) between two groups. The proportion of histologic core and the diagnostic accuracy were comparable between the FNB and FNA groups. However, fewer needle passes were required to establish an accurate diagnosis in EUS-FNB.

Methodology for Knowledge Synthesis of the Management of Vaccination Pain and Needle Fear.

Science.gov (United States)

Taddio, Anna; McMurtry, C Meghan; Shah, Vibhuti; Yoon, Eugene W; Uleryk, Elizabeth; Pillai Riddell, Rebecca; Lang, Eddy; Chambers, Christine T; Noel, Melanie; MacDonald, Noni E

2015-10-01

A knowledge synthesis was undertaken to inform the development of a revised and expanded clinical practice guideline about managing vaccination pain in children to include the management of pain across the lifespan and the management of fear in individuals with high levels of needle fear. This manuscript describes the methodological details of the knowledge synthesis and presents the list of included clinical questions, critical and important outcomes, search strategy, and search strategy results. The Grading of Assessments, Recommendations, Development and Evaluation (GRADE) and Cochrane methodologies provided the general framework. The project team voted on clinical questions for inclusion and critically important and important outcomes. A broad search strategy was used to identify relevant randomized-controlled trials and quasi-randomized-controlled trials. Quality of research evidence was assessed using the Cochrane risk of bias tool and quality across studies was assessed using GRADE. Multiple measures of the same construct within studies (eg, observer-rated and parent-rated infant distress) were combined before pooling. The standardized mean difference and 95% confidence intervals (CI) or relative risk and 95% CI was used to express the effects of an intervention. Altogether, 55 clinical questions were selected for inclusion in the knowledge synthesis; 49 pertained to pain management during vaccine injections and 6 pertained to fear management in individuals with high levels of needle fear. Pain, fear, and distress were typically prioritized as critically important outcomes across clinical questions. The search strategy identified 136 relevant studies. This manuscript describes the methodological details of a knowledge synthesis about pain management during vaccination and fear management in individuals with high levels of needle fear. Subsequent manuscripts in this series will present the results for the included questions.

Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

International Nuclear Information System (INIS)

Thompson, S.A.; Fung, A.Y.C.; Zaider, M.

2002-01-01

One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results. (author)

Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

Energy Technology Data Exchange (ETDEWEB)

Thompson, S.A. [Department of Medical Physics, North Shore-Long Island Jewish Health System, Manhassett, NY (United States); Fung, A.Y.C.; Zaider, M. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2002-08-21

One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results. (author)

The Hydrodynamics of Needle-Free Intradermal Jet Injection

Science.gov (United States)

Simmons, Jonathan; Marston, Jeremy; Fisher, Paul; Broderick, Kate

2017-11-01

Needle-free methods of drug delivery circumvent the drawbacks associated with the use of hypodermic needles such as needle-stick injuries, needle-phobia, cross contamination and disposal. Furthermore, pioneering DNA-based vaccines that aim to treat cancer and fight infectious diseases, such as HIV, Ebola and Zika, require precise deposition into the skin to target the immune response producing cells found only in the epidermis and dermis. Intradermal (ID) delivery can be achieved using a needle and the Mantoux technique but this requires a highly skilled technician and so extensive use of DNA vaccines calls for an alternative method of delivery. One option is jet injection which has been employed in mass vaccination programs for intramuscular or subcutaneous delivery and is used by some diabetic patients to inject insulin. In this talk I will present results from our ongoing ex-vivo experimental study into ID jet injection. Ultra-high-speed imaging is used to visualize the process of the jet exiting the nozzle and striking excised skin. A skin bleb grows as liquid is deposited within the skin. I will discuss how the control parameters, such as the rheological profile of the liquid and the stand-off distance, influence the volume of liquid successfully delivered intradermally.

Improving needle tip identification during ultrasound-guided procedures in anaesthetic practice

NARCIS (Netherlands)

Scholten, H.J.; Pourtaherian, A.; Mihajlovic, N.; Korsten, H.; Bouwman, R.A.

2017-01-01

Ultrasound guidance is becoming standard practice for needle-based interventions in anaesthetic practice, such as vascular access and peripheral nerve blocks. However, difficulties in aligning the needle and the transducer can lead to incorrect identification of the needle tip, possibly damaging

Single-incision laparoscopic cholecystectomy with needle graspers.

Science.gov (United States)

Sumiyoshi, Kinjiro; Sato, Norihiro; Akagawa, Shin; Hirano, Tatsuya; Koikawa, Kazuhiro; Horioka, Kohei; Ozono, Keigo; Fujiwara, Kenji; Tanaka, Masao; Sada, Masayuki

2012-01-01

Single-incision laparoscopic cholecystectomy (SILC) is a promising alternative to standard multi-incision laparoscopic cholecystectomy (LC). However, generalization of SILC is still hampered by technical difficulties mainly associated with the lack of trocars used for retraction of the gallbladder. We therefore developed a modified method of SILC with the use of needle graspers (SILC-N) for optimal retraction and exposure. In addition to two trocars inserted through a single transumbilical incision, two needle ports were placed on the right subcostal and lateral abdominal wall, through which needle graspers were used for retraction of the gallbladder. Since December, 2009, 12 patients with symptomatic cholelithiasis were treated by SILC-N. SILC-N was successfully performed in all but one patient requiring a conversion to the 4-port LC with a mean operative time of 71.5 (48-107) minutes. None of the patients experienced intraoperative or postoperative complications. The transumbilical incision and pinholes for needle graspers were almost invisible on discharge. Our preliminary results suggest that SILC-N is a simple, safe and feasible technique of cholecystectomy offering similar postoperative recovery and better cosmetic outcome as compared to conventional LC.

Needle-shaped and platelet growth of borax crystals

International Nuclear Information System (INIS)

Takoo, R.K.; Patel, B.R.; Joshi, M.S.

1983-01-01

Needle-shaped and platelet growth of borax crystals from solutions is reported. Results of microtopographical studies on both the varieties are discussed. It is suggested that a slow rate of evaporation favours needle growth and a faster rate is conducive to the growth of platelets. (author)

Discordance Rate between Thyroid Fine Needle Aspiration Cytology ...

African Journals Online (AJOL)

Discordance Rate between Thyroid Fine Needle Aspiration Cytology and Histopathologic Diagnosis. Wondwossen Ergete, Daniel Abebe. Abstract. Fine Needle Aspiration (FNA) of the thyroid is a low cost procedure, which can give an accurate diagnosis promptly. The objective of this study was to assess the diagnostic ...

Biopsy Needle Localization and Tracking Using ROI-RK Method

Directory of Open Access Journals (Sweden)

Yue Zhao

2014-01-01

Full Text Available ROI-RK method is a biopsy needle localization and tracking method. Previous research work has proved that it has a robust performance on different series of simulated 3D US volumes. Unfortunately, in real situations, because of the strong speckle noise of the ultrasound image and the different echogenic properties of the tissues, the real 3D US volumes have more complex background than the simulated images used previously. In this paper, to adapt the ROI-RK method in real 3D US volumes, a line-filter enhancement calculation only in the ROI is added to increase the contrast between the needle and background tissue, decreasing the phenomenon of expansion of the biopsy needle due to reverberation of ultrasound in the needle. To make the ROI-RK method more stable, a self-correction system is also implemented. Real data have been acquired on an ex vivo heart of lamb. The result of the ROI-RK method shows that it is capable to localize and track the biopsy needle in real situations, and it satisfies the demand of real-time application.

Determination of rare earth elements in the biological reference materials Pine Needles and Spruce Needles by neutron activation analysis

International Nuclear Information System (INIS)

Machado, C.N.; Maria, S.P.; Saiki, M.; Figueiredo, A.M.G.

1998-01-01

Instrumental neutron activation analysis was applied to determine La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and Sc in two biological reference materials: NIST 1575 Pine Needles and BCR-CRM 101 Spruce Needles. The purpose was to contribute to the reference data for these two reference materials. The results were obtained with a good precision (relative standard deviations less than 15%). For the Pine Needles reference material there are already some proposed values and our results showed, in general, a good agreement with the data published. The contribution of uranium fission products to La, Ce, Nd and Sm was evaluated and considered in the determination of these elements. Interferences in the determination of rare earth elements in biological materials are also discussed. (author)

Novel design of honeybee-inspired needles for percutaneous procedure.

Science.gov (United States)

Sahlabadi, Mohammad; Hutapea, Parsaoran

2018-04-18

The focus of this paper is to present new designs of innovative bioinspired needles to be used during percutaneous procedures. Insect stingers have been known to easily penetrate soft tissues. Bioinspired needles mimicking the barbs in a honeybee stinger were developed for a smaller insertion force, which can provide a less invasive procedure. Decreasing the insertion force will decrease the tissue deformation, which is essential for more accurate targeting. In this study, some design parameters, in particular, barb shape and geometry (i.e. front angle, back angle, and height) were defined, and their effects on the insertion force were investigated. Three-dimensional printing technology was used to manufacture bioinspired needles. A specially-designed insertion test setup using tissue mimicking polyvinyl chloride (PVC) gels was developed to measure the insertion and extraction forces. The barb design parameters were then experimentally modified through detailed experimental procedures to further reduce the insertion force. Different scales of the barbed needles were designed and used to explore the size-scale effect on the insertion force. To further investigate the efficacy of the proposed needle design in real surgeries, preliminary ex vivo insertion tests into bovine liver tissue were performed. Our results show that the insertion force of the needles in different scales decreased by 21-35% in PVC gel insertion tests, and by 46% in bovine liver tissue insertion tests.

Skin Blood Perfusion and Cellular Response to Insertion of Insulin Pen Needles With Different Diameters

DEFF Research Database (Denmark)

Præstmark, Kezia Ann; Stallknecht, Bente Merete; Bo Jensen, Casper

2014-01-01

skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after...... blood perfusion recording and grouped according to needle type, skin blood perfusion response relates to needle diameter. The response was significantly higher after insertions with 28G and hooked 32G needles than with 30G (P ..., but there was a trend of an increased response with increasing needle diameter. Skin blood perfusion response to pen needle insertions rank according to needle diameter, and the tissue response caused by hooked 32G needles corresponds to that of 28G needles. The relation between needle diameter and trauma when...

The influence of Lampblack on capacity retention in Pb/PbSO/sub 4/ electrodes with forced flow of electrolyte

Energy Technology Data Exchange (ETDEWEB)

Borger, W.; Hullmeine, U.

1984-10-01

High active material utilization of Pb/PbSO/sub 4/ electrodes after formation in the range of 170 - 120 Ah/kg is obtained when these electrodes are discharged at 50-200 A/kg current density with forced flow of electrolyte. Decline of capacity was observed on further cycling at high current density and forced flow of electrolyte. The extent of capacity decline in these electrodes is largely influenced by the amount of additives in the active material, e.g. lampblack and expander.

Fine needle diagnosis in lumbar osteomyelitis

International Nuclear Information System (INIS)

Joshi, K.B.; Brinker, R.A.

1983-01-01

Lumbar vertebral body and disk infection, presenting as low back pain, is a relatively uncommon disease but is seen more often in drug addicts. Radiographs show typical changes of infection of the lumbar vertebrae and adjacent disc. Under local anesthesia a fine needle is placed, saline injected, and aspirated. The entire needle-syringe unit is submitted to the bacteriology department. Pseudomonas infection is usually found. This method of diagnosis is simple, cost effective, well accepted by the patients, and can be done on outpatients. (orig.)

Radiofrequency ablation of small hepatocellular carcinoma : early experience of efficacy and safety

International Nuclear Information System (INIS)

Choi, Dongil; Lim, Hyo Keun; Kim, Seung Hoon; And Others

2000-01-01

To evaluate the efficacy and safety of radiofrequency (RF) ablation for the treatment of small hepatocellular carcinoma (HCC). Forty-four patients with 51 HCCs underwent ultrasound guided RF ablation using expandable needle electrodes and monopolar RF generator. The patients were not considered suitable candidates for surgery or declined this option, and had no history of previous treatment. Mean tumor diameter was 2.5 cm (range, 1.0-4.0 cm). Therapeutic efficacy was evaluated by means of three-phase helical computed tomography (CT) performed at least one month after the completion of ablation. The recurrence rate was also evaluated by follow-up CT at least four months after treatment. Using RF ablation, complete necrosis was achieved in 48 of 51 tumors (94%). Among 20 patients in whom follow-up CT was performed at least four months after ablation, one (5%) showed marginal recurrence and in another (5%) there was recurrence in remote liver parenchyma. We experienced neither procedure-related mortality nor major complications which required specific treatment. Three minor complications (one small pneumothorax and two cases of intraperitoneal bleeding) occurred, but these disappeared without specific treatment. RF ablation using an expandable needle electrode showed a high rate of complete necrosis and a low rate of complications. The technique is therefore considered effective and safe for the local control of small HCCs. (author)

Kalman filter-based EM-optical sensor fusion for needle deflection estimation.

Science.gov (United States)

Jiang, Baichuan; Gao, Wenpeng; Kacher, Daniel; Nevo, Erez; Fetics, Barry; Lee, Thomas C; Jayender, Jagadeesan

2018-04-01

In many clinical procedures such as cryoablation that involves needle insertion, accurate placement of the needle's tip at the desired target is the major issue for optimizing the treatment and minimizing damage to the neighboring anatomy. However, due to the interaction force between the needle and tissue, considerable error in intraoperative tracking of the needle tip can be observed as needle deflects. In this paper, measurements data from an optical sensor at the needle base and a magnetic resonance (MR) gradient field-driven electromagnetic (EM) sensor placed 10 cm from the needle tip are used within a model-integrated Kalman filter-based sensor fusion scheme. Bending model-based estimations and EM-based direct estimation are used as the measurement vectors in the Kalman filter, thus establishing an online estimation approach. Static tip bending experiments show that the fusion method can reduce the mean error of the tip position estimation from 29.23 mm of the optical sensor-based approach to 3.15 mm of the fusion-based approach and from 39.96 to 6.90 mm, at the MRI isocenter and the MRI entrance, respectively. This work established a novel sensor fusion scheme that incorporates model information, which enables real-time tracking of needle deflection with MRI compatibility, in a free-hand operating setup.

Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid

Science.gov (United States)

... Physician Resources Professions Site Index A-Z Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid An ... Aspiration Biopsy of the Thyroid? What is Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid? During ...

Oblique needle segmentation and tracking for 3D TRUS guided prostate brachytherapy

International Nuclear Information System (INIS)

Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

2005-01-01

An algorithm was developed in order to segment and track brachytherapy needles inserted along oblique trajectories. Three-dimensional (3D) transrectal ultrasound (TRUS) images of the rigid rod simulating the needle inserted into the tissue-mimicking agar and chicken breast phantoms were obtained to test the accuracy of the algorithm under ideal conditions. Because the robot possesses high positioning and angulation accuracies, we used the robot as a ''gold standard,'' and compared the results of algorithm segmentation to the values measured by the robot. Our testing results showed that the accuracy of the needle segmentation algorithm depends on the needle insertion distance into the 3D TRUS image and the angulations with respect to the TRUS transducer, e.g., at a 10 deg. insertion anglulation in agar phantoms, the error of the algorithm in determining the needle tip position was less than 1 mm when the insertion distance was greater than 15 mm. Near real-time needle tracking was achieved by scanning a small volume containing the needle. Our tests also showed that, the segmentation time was less than 60 ms, and the scanning time was less than 1.2 s, when the insertion distance into the 3D TRUS image was less than 55 mm. In our needle tracking tests in chicken breast phantoms, the errors in determining the needle orientation were less than 2 deg. in robot yaw and 0.7 deg. in robot pitch orientations, for up to 20 deg. needle insertion angles with the TRUS transducer in the horizontal plane when the needle insertion distance was greater than 15 mm

Transcription through the eye of a needle: daily and annual cyclic gene expression variation in Douglas-fir needles

OpenAIRE

Cronn, Richard; Dolan, Peter C.; Jogdeo, Sanjuro; Wegrzyn, Jill L.; Neale, David B.; St. Clair, J. Bradley; Denver, Dee R.

2017-01-01

Background Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal cycles and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii) n...

Performance and applications of the ORNL local electrode atom probe

International Nuclear Information System (INIS)

Miller, M.K.; Russell, K.F.

2004-01-01

Full text: The commercial introduction in 2003 of the local electrode atom probe (LEAP) developed by Imago Scientific Instruments has made dramatic, orders of magnitude improvements in the data acquisition rate and the size of the analyzed volume compared to previous types of three-dimensional atom probes and other scanning atom probes. This state-of-the-art instrument may be used for the analysis of traditional needle-shaped specimens and specimens fabricated from 'flat' specimens with focused ion beam (FIB) techniques. The advantage of this local electrode configuration is that significantly lower (∼50 %) standing and pulse voltages are required to produce the field strength required to field evaporate ions from the specimen. New high speed (200 kHz) pulse generators coupled with crossed delay line detectors and faster timing systems also enable significantly faster (up to 300 times) data acquisition rates to be achieved. This new design also permits a significantly larger field of view to be analyzed and results in data sets containing up to 10 8 atoms. In the local electrode atom probe, a ∼10-50 μm diameter aperture is typically positioned approximately one aperture diameter in front of the specimen. In order to accurately align the specimen to the aperture in the funnel-shaped electrode, the specimen is mounted on a three axis nanopositioning stage. An approximate alignment is performed while viewing the relative positions of the specimen and the local electrode with a pair of low magnification video cameras and then a pair of higher magnification video cameras attached to long range microscopes. The final alignment is performed with the use of the field evaporated ions from the specimen. A discussion on the alignment of the specimen with the local electrode, the effects of the fields on the specimen, and the effects of aperture size on aperture lifetime will be presented. The performance of the ORNL local electrode atom probe will be described. The

[Professor Feng Run-Shen's essential experience in penetration needling method].

Science.gov (United States)

Feng, Mu-Lan

2009-04-01

Professor Feng Run-Shen is engaged in medicine for more than 60 years. He pays attention to medical ethics and has perfect medical skill. He energetically advocates combination of acupuncture with medication and stresses the concept of viewing the situation as a whole in selection of acupoints and treatment, particularly, clinical application of point properties. Clinically, he is accomplished in penetration needling, for which one needle acts on two or more points, enlarging the range of needling sensation, so it has very good therapeutic effects on many diseases. In the paper, the case samples about penetration needling in his clinical practice are summarized and introduced.

Fine Needle Aspiration Cytology In Tumour Diagnosis | Obaseki ...

African Journals Online (AJOL)

Fine needle aspiration cytology (FNAC), a technique for obtaining cellular material for cytological examination and diagnosis using a 21- gauge or smaller needle, is performed using a 5, 10, or 20ml syringe either freehand or using special syringe holders. It allows a minimally invasive, rapid diagnosis of tissue samples but

Improved radionuclide bone imaging agent injection needle withdrawal method can improve image quality

International Nuclear Information System (INIS)

Qin Yongmei; Wang Laihao; Zhao Lihua; Guo Xiaogang; Kong Qingfeng

2009-01-01

Objective: To investigate the improvement of radionuclide bone imaging agent injection needle withdrawal method on whole body bone scan image quality. Methods: Elbow vein injection syringe needle directly into the bone imaging agent in the routine group of 117 cases, with a cotton swab needle injection method for the rapid pull out the needle puncture point pressing, pressing moment. Improvement of 117 cases of needle injection method to put two needles into the skin swabs and blood vessels, pull out the needle while pressing two or more entry point 5min. After 2 hours underwent whole body bone SPECT imaging plane. Results: The conventional group at the injection site imaging agents uptake rate was 16.24%, improved group was 2.56%. Conclusion: The modified bone imaging agent injection needle withdrawal method, injection-site imaging agent uptake were significantly decreased whole body bone imaging can improve image quality. (authors)

Needle-free influenza vaccination

NARCIS (Netherlands)

Amorij, Jean-Pierre; Hinrichs, Wouter L.J.; Frijlink, Henderik W.; Wilschut, Jan C.; Huckriede, Anke

2010-01-01

Vaccination is the cornerstone of influenza control in epidemic and pandemic situations. Influenza vaccines are typically given by intramuscular injection. However, needle-free vaccinations could offer several distinct advantages over intramuscular injections: they are pain-free, easier to

Improvement of Depth Profiling into Biotissues Using Micro Electrical Impedance Spectroscopy on a Needle with Selective Passivation.

Science.gov (United States)

Yun, Joho; Kim, Hyeon Woo; Lee, Jong-Hyun

2016-12-21

A micro electrical impedance spectroscopy (EIS)-on-a-needle for depth profiling (μEoN-DP) with a selective passivation layer (SPL) on a hypodermic needle was recently fabricated to measure the electrical impedance of biotissues along with the penetration depths. The SPL of the μEoN-DP enabled the sensing interdigitated electrodes (IDEs) to contribute predominantly to the measurement by reducing the relative influence of the connection lines on the sensor output. The discrimination capability of the μEoN-DP was verified using phosphate-buffered saline (PBS) at various concentration levels. The resistance and capacitance extracted through curve fitting were similar to those theoretically estimated based on the mixing ratio of PBS and deionized water; the maximum discrepancies were 8.02% and 1.85%, respectively. Depth profiling was conducted using four-layered porcine tissue to verify the effectiveness of the discrimination capability of the μEoN-DP. The magnitude and phase between dissimilar porcine tissues (fat and muscle) were clearly discriminated at the optimal frequency of 1 MHz. Two kinds of simulations, one with SPL and the other with complete passivation layer (CPL), were performed, and it was verified that the SPL was advantageous over CPL in the discrimination of biotissues in terms of sensor output.

Improvement of Depth Profiling into Biotissues Using Micro Electrical Impedance Spectroscopy on a Needle with Selective Passivation

Directory of Open Access Journals (Sweden)

Joho Yun

2016-12-01

Full Text Available A micro electrical impedance spectroscopy (EIS-on-a-needle for depth profiling (μEoN-DP with a selective passivation layer (SPL on a hypodermic needle was recently fabricated to measure the electrical impedance of biotissues along with the penetration depths. The SPL of the μEoN-DP enabled the sensing interdigitated electrodes (IDEs to contribute predominantly to the measurement by reducing the relative influence of the connection lines on the sensor output. The discrimination capability of the μEoN-DP was verified using phosphate-buffered saline (PBS at various concentration levels. The resistance and capacitance extracted through curve fitting were similar to those theoretically estimated based on the mixing ratio of PBS and deionized water; the maximum discrepancies were 8.02% and 1.85%, respectively. Depth profiling was conducted using four-layered porcine tissue to verify the effectiveness of the discrimination capability of the μEoN-DP. The magnitude and phase between dissimilar porcine tissues (fat and muscle were clearly discriminated at the optimal frequency of 1 MHz. Two kinds of simulations, one with SPL and the other with complete passivation layer (CPL, were performed, and it was verified that the SPL was advantageous over CPL in the discrimination of biotissues in terms of sensor output.

Helical-Tip Needle for Transthoracic Percutaneous Image-Guided Biopsy of Lung Tumors: Results of a Pilot Prospective Comparative Study with a Standard Tru-Cut Needle

Energy Technology Data Exchange (ETDEWEB)

Veltri, Andrea, E-mail: andrea.veltri@unito.it; Busso, Marco; Sardo, Diego; Angelino, Valeria; Priola, Adriano M. [University of Torino, Department of Radiology, San Luigi Gonzaga Hospital (Italy); Novello, Silvia [University of Torino, Department of Oncology, San Luigi Gonzaga Hospital (Italy); Barba, Matteo [University of Torino, Department of Radiology, San Luigi Gonzaga Hospital (Italy); Gatti, Gaia; Righi, Luisella [University of Torino, Department of Pathology, San Luigi Gonzaga Hospital (Italy)

2017-06-15

PurposeTo prospectively evaluate feasibility and diagnostic performance of the 14-gauge helical-tip (Spirotome™, Cook{sup ®} Medical, Bloomington, USA) needle in transthoracic needle biopsy (TTNB) of lung lesions, compared to a conventional 18-gauge Tru-Cut needle.Materials and MethodsStudy was institutional review board approved, with informed consent obtained. Data from synchronous Spirotome and Tru-Cut image-guided TTNB of 20 consecutive patients with malignant peripheral lung tumors larger than 3 cm were enrolled for pathologic characterization and mutational analysis. Samples obtained with Spirotome and Tru-Cut needle were compared for fragmentation, length, weight, morphologic and immunohistochemistry typifying, tumor cellularity (TC) and DNA concentration.ResultsThe technical success rate for TTNB with Spirotome was 100%, and no major complications occurred. Less fragmentation (mean 2 vs. 3 fragments, P = .418), greater weight (mean 13 vs. 8.5 mg, P = .027) and lower length (mean 10.2 vs. 12.6 mm, P = .174) were observed with Spirotome compared to Tru-Cut needle. Accuracy of Spirotome and Tru-Cut needle in defining cancer histotype was similar (90%). Absolute and relative TC (mean 42 vs. 38, 124 vs. 108/10HPF), and DNA concentration (mean 49.6 vs. 39.0 ng/μl) were higher with Spirotome compared to Tru-Cut needle, with no statistical significance (P = .787 and P = .140, respectively).Conclusions Percutaneous 14-gauge Spirotome TTNB of selected lesions is feasible and accurate. It provides adequate samples for diagnosis, comparable to 18-gauge Tru-Cut needle, with a higher amount of tumor tissue (weight, TC, DNA concentration) even in shorter samples.

A variable stiffness mechanism for steerable percutaneous instruments: integration in a needle.

Science.gov (United States)

De Falco, Iris; Culmone, Costanza; Menciassi, Arianna; Dankelman, Jenny; van den Dobbelsteen, John J

2018-06-04

Needles are advanced tools commonly used in minimally invasive medical procedures. The accurate manoeuvrability of flexible needles through soft tissues is strongly determined by variations in tissue stiffness, which affects the needle-tissue interaction and thus causes needle deflection. This work presents a variable stiffness mechanism for percutaneous needles capable of compensating for variations in tissue stiffness and undesirable trajectory changes. It is composed of compliant segments and rigid plates alternately connected in series and longitudinally crossed by four cables. The tensioning of the cables allows the omnidirectional steering of the tip and the stiffness tuning of the needle. The mechanism was tested separately under different working conditions, demonstrating a capability to exert up to 3.6 N. Afterwards, the mechanism was integrated into a needle, and the overall device was tested in gelatine phantoms simulating the stiffness of biological tissues. The needle demonstrated the capability to vary deflection (from 11.6 to 4.4 mm) and adapt to the inhomogeneity of the phantoms (from 21 to 80 kPa) depending on the activation of the variable stiffness mechanism. Graphical abstract ᅟ.

Surface Area Expansion of Electrodes with Grass-like Nanostructures to Enhance Electricity Generation in Microbial Fuel Cells

DEFF Research Database (Denmark)

Al Atraktchi, Fatima Al-Zahraa; Zhang, Yifeng; Noori, Jafar Safaa

2012-01-01

Microbial fuel cells (MFCs) have applications possibilities for wastewater treatment, biotransformation, and biosensor, but the development of highly efficient electrode materials is critical for enhancing the power generation. Two types of electrodes modified with nanoparticles or grass-like nan......Microbial fuel cells (MFCs) have applications possibilities for wastewater treatment, biotransformation, and biosensor, but the development of highly efficient electrode materials is critical for enhancing the power generation. Two types of electrodes modified with nanoparticles or grass...... of plain silicium showed a maximum power density of 86.0 mW/m2. Further expanding the surface area of carbon paper electrodes with gold nanoparticles resulted in a maximum stable power density of 346.9 mW/m2 which is 2.9 times higher than that achieved with conventional carbon paper. These results show...

A study on applying Ra needle interstitial brachytherapy for oral cancer

International Nuclear Information System (INIS)

Yoshida, Shunichi; Komiya, Yoshiaki; Uchida, Ikuhiro; Tashiro, Kazuyoshi

1999-01-01

To investigate applicability of Ra needle interstitial brachytherapy, 93 cases of oral squamous carcinoma were examined. The patients underwent Ra needle interstitial brachytherapy as thorough therapy in our hospital. The criteria of applying Ra needle interstitial brachytherapy was diameter of within 5 cm and depth within 2 cm of tumor size. Ra needle interstitial brachytherapy was applied to 82 cases of tongue, 10 cases of oral floor and one case of lower lip carcinomas. The local control rate was 92.5%, and secondary neck metastasis was 32.3% in all cases applied Ra needle interstitial brachytherapy. The results were not bad compared with surgical treatment. However, the 5-year cumulative survival rate was 64.9%, which was not good enough at the result to obtain a good local control rate and secondary neck metastasis rate. The result was relative to low treatment result of local recurrence cases with Ra needle interstitial brachytherapy. To improve the result, it is important to distinguish local recurrence from radioinduced ulcer, and to start early secondary treatment. The cases in which cervical lymph node metastasis was found as the first examination underwent neck dessection after Ra needle interstitial brachytherapy. The 5-year cumulative survival rate was 83.3% in N1 cases and 40.6% in N2 cases, and the result of N2 cases was poorer than N1 cases with a significant difference. The results indicate that a needle having a diameter of within 5 cm, depth of within 2 cm and less than N1 can be applied during Ra needle interstitial brachytherapy for complete cure of cancer. (author)

SU-D-213AB-06: Surface Texture and Insertion Speed Effect on Needle Friction.

Science.gov (United States)

Abdullah, A; Golecki, C; Barnett, A; Moore, J

2012-06-01

High frictional forces between the needle surface and tissue cause tissue deflection which hinders accurate needle placement for procedures such as brachytherapy and needle biopsy. Accurate needle placement isimportant to maximize procedure efficacy. This work investigates how needle surface roughness and insertion speed affect the frictional forcebetween a needle and tissue. A friction experiment was conducted to measure the force of friction between bovine liver and three 11 gauge needles having Ra surface roughness of 3.43, 1.33, and 0.2 μm. Each of the three needles were mounted on a linear slide and were advanced and retracted through bovine liver at speeds of 50, 100, 150, and 200 mm/s for a total of 12 trials. In each trial the needle was advanced and retracted in 10 cycles producing a steady state insertion force and a steady state retraction force for each cycle. A force sensor connecting the needle to the linear slide recorded the resistance force of the needle sliding through the liver. The liver was mounted in a box with a pneumatic cylinder which compressed the liver sample by 11.65 kPa. The roughest needle (Ra = 3.43 μm) on average produced 68, 73, 74, and 73% lower friction force than the smoothest needle (Ra = 0.2 μm) for the speeds of 50, 100, 150, and 200mm/s, respectively. The second roughest needle (Ra = 1.33 μm) on average produced 25, 45, 60 and 64% lower friction force than the smoothest needle (Ra = 0.2 μm) for the speeds of 50, 100, 150, and 200 mm/s, respectively. Rougher needle surface texture and higher insertion speed reduced frictional forces between the tissue and the needle. Future studies will examine how frictional forces can be modeled and predicted given surface texture and insertion speed. © 2012 American Association of Physicists in Medicine.

Virtual electrodes for high-density electrode arrays

Science.gov (United States)

Cela, Carlos J.; Lazzi, Gianluca

2015-10-13

The present embodiments are directed to implantable electrode arrays having virtual electrodes. The virtual electrodes may improve the resolution of the implantable electrode array without the burden of corresponding complexity of electronic circuitry and wiring. In a particular embodiment, a virtual electrode may include one or more passive elements to help steer current to a specific location between the active electrodes. For example, a passive element may be a metalized layer on a substrate that is adjacent to, but not directly connected to an active electrode. In certain embodiments, an active electrode may be directly coupled to a power source via a conductive connection. Beneficially, the passive elements may help to increase the overall resolution of the implantable array by providing additional stimulation points without requiring additional wiring or driver circuitry for the passive elements.

Students as effective harm reductionists and needle exchange organizers.

Science.gov (United States)

Barbour, Kyle; McQuade, Miriam; Brown, Brandon

2017-03-17

Needle exchange programs are safe, highly effective programs for promoting health among people who inject drugs. However, they remain poorly funded, and often illegal, in many places worldwide due to fear and stigma surrounding drug use. Continued advocacy, education, and implementation of new needle exchanges are thus essential to improve public health and reduce structural inequality. We argue that students, and especially professional and graduate students, have the potential to play an important role in advancing harm reduction. Students benefit from the respect given to the professions they are training to enter, which gives them leverage to navigate the political hurdles often faced by needle exchange organizers, especially in areas that presently lack services. In addition, due to their relative simplicity, needle exchanges do not require much of the licensing, clinical knowledge, and infrastructure associated with more traditional student programs, such as student-run free medical clinics. Students are capable of learning harm reduction cultural approaches and techniques if they remain humble, open-minded, and seek the help of the harm reduction community. Consequently, students can generate tremendous benefits to their community without performing beyond their appropriate clinical limitations. Students benefit from organizing needle exchanges by gaining applied experience in advocacy, organization-building, and political finesse. Working in a needle exchange significantly helps erode stigma against multiple marginalized populations. Students in health-related professions additionally learn clinically-relevant knowledge that is often lacking from their formal training, such as an understanding of structural violence and inequality, root causes of substance use, client-centered approaches to health services, and interacting with clients as peers, rather than through the standard hierarchical medical interaction. We therefore encourage students to learn about

Smartphone-Guided Needle Angle Selection During CT-Guided Procedures.

Science.gov (United States)

Xu, Sheng; Krishnasamy, Venkatesh; Levy, Elliot; Li, Ming; Tse, Zion Tsz Ho; Wood, Bradford John

2018-01-01

In CT-guided intervention, translation from a planned needle insertion angle to the actual insertion angle is estimated only with the physician's visuospatial abilities. An iPhone app was developed to reduce reliance on operator ability to estimate and reproduce angles. The iPhone app overlays the planned angle on the smartphone's camera display in real-time based on the smartphone's orientation. The needle's angle is selected by visually comparing the actual needle with the guideline in the display. If the smartphone's screen is perpendicular to the planned path, the smartphone shows the Bull's-Eye View mode, in which the angle is selected after the needle's hub overlaps the tip in the camera. In phantom studies, we evaluated the accuracies of the hardware, the Guideline mode, and the Bull's-Eye View mode and showed the app's clinical efficacy. A proof-of-concept clinical case was also performed. The hardware accuracy was 0.37° ± 0.27° (mean ± SD). The mean error and navigation time were 1.0° ± 0.9° and 8.7 ± 2.3 seconds for a senior radiologist with 25 years' experience and 1.5° ± 1.3° and 8.0 ± 1.6 seconds for a junior radiologist with 4 years' experience. The accuracy of the Bull's-Eye View mode was 2.9° ± 1.1°. Combined CT and smart-phone guidance was significantly more accurate than CT-only guidance for the first needle pass (p = 0.046), which led to a smaller final targeting error (mean distance from needle tip to target, 2.5 vs 7.9 mm). Mobile devices can be useful for guiding needle-based interventions. The hardware is low cost and widely available. The method is accurate, effective, and easy to implement.

Detection of Membrane Puncture with Haptic Feedback using a Tip-Force Sensing Needle.

Science.gov (United States)

Elayaperumal, Santhi; Bae, Jung Hwa; Daniel, Bruce L; Cutkosky, Mark R

2014-09-01

This paper presents calibration and user test results of a 3-D tip-force sensing needle with haptic feedback. The needle is a modified MRI-compatible biopsy needle with embedded fiber Bragg grating (FBG) sensors for strain detection. After calibration, the needle is interrogated at 2 kHz, and dynamic forces are displayed remotely with a voice coil actuator. The needle is tested in a single-axis master/slave system, with the voice coil haptic display at the master, and the needle at the slave end. Tissue phantoms with embedded membranes were used to determine the ability of the tip-force sensors to provide real-time haptic feedback as compared to external sensors at the needle base during needle insertion via the master/slave system. Subjects were able to determine the position of the embedded membranes with significantly better accuracy using FBG tip feedback than with base feedback using a commercial force/torque sensor (p = 0.045) or with no added haptic feedback (p = 0.0024).

A needle guidance system for biopsy and therapy using two-dimensional ultrasound

International Nuclear Information System (INIS)

Bluvol, Nathan; Sheikh, Allison; Kornecki, Anat; Del Rey Fernandez, David; Downey, Donal; Fenster, Aaron

2008-01-01

Image-guided needle biopsies are currently used to provide a definitive diagnosis of breast cancer; however, difficulties in tumor targeting exist as the ultrasound (United States) scan plane and biopsy needle must remain coplanar throughout the procedure to display the actual needle tip position. The additional time associated with aligning and maintaining this coplanar relationship results in increased patient discomfort. Biopsy procedural efficiency is further hindered since needle pathway interpretation is often difficult, especially for needle insertions at large depths that usually require multiple reinsertions. The authors developed a system that would increase the speed and accuracy of current breast biopsy procedures using readily available two-dimensional (2D) US technology. This system is composed of a passive articulated mechanical arm that attaches to a 2D US transducer. The arm is connected to a computer through custom electronics and software, which were developed as an interface for tracking the positioning of the mechanical components in real time. The arm couples to the biopsy needle and provides visual guidance for the physician performing the procedure in the form of a real-time projected needle pathway overlay on an US image of the breast. An agar test phantom, with stainless steel targets interspersed randomly throughout, was used to validate needle trajectory positioning accuracy. The biopsy needle was guided by both the software and hardware components to the targets. The phantom, with the needle inserted and device decoupled, was placed in an x-ray stereotactic mammography (SM) machine. The needle trajectory and bead target locations were determined in three dimensions from the SM images. Results indicated a mean needle trajectory accuracy error of 0.75±0.42 mm. This is adequate to sample lesions that are <2 mm in diameter. Chicken tissue test phantoms were used to compare core needle biopsy procedure times between experienced radiologists

In vivo motion and force measurement of surgical needle intervention during prostate brachytherapy

International Nuclear Information System (INIS)

Podder, Tarun; Clark, Douglas; Sherman, Jason; Fuller, Dave; Messing, Edward; Rubens, Deborah; Strang, John; Brasacchio, Ralph; Liao, Lydia; Ng, W.-S.; Yu Yan

2006-01-01

In this paper, we present needle insertion forces and motion trajectories measured during actual brachytherapy needle insertion while implanting radioactive seeds in the prostate glands of 20 different patients. The needle motion was captured using ultrasound images and a 6 degree-of-freedom electromagnetic-based position sensor. Needle velocity was computed from the position information and the corresponding time stamps. From in vivo data we found the maximum needle insertion forces to be about 15.6 and 8.9 N for 17 gauge (1.47 mm) and 18 gauge (1.27 mm) needles, respectively. Part of this difference in insertion forces is due to the needle size difference (17G and 18G) and the other part is due to the difference in tissue properties that are specific to the individual patient. Some transverse forces were observed, which are attributed to several factors such as tissue heterogeneity, organ movement, human factors in surgery, and the interaction between the template and the needle. However, theses insertion forces are significantly responsible for needle deviation from the desired trajectory and target movement. Therefore, a proper selection of needle and modulated velocity (translational and rotational) may reduce the tissue deformation and target movement by reducing insertion forces and thereby improve the seed delivery accuracy. The knowledge gleaned from this study promises to be useful for not only designing mechanical/robotic systems but also developing a predictive deformation model of the prostate and real-time adaptive controlling of the needle

[Treatment of Persistent Somatoform Pain Disorder by Floating Needle Therapy and Duloxetine].

Science.gov (United States)

Ren, Wan-wen; Zhou, Zhi-ying; Xu, Mi-mi; Long, Sen; Tang, Guang-zheng; Mao, Hong-jing; Chen, Shu-lin

2016-02-01

To evaluate clinical effect and safety of floating needle therapy and duloxetine in treating patients with persistent somatoform pain disorder (PSPD). Totally 108 PSPD patients were randomly assigned to the floating needle treatment group, the duloxetine treatment group, and the placebo treatment group, 36 in each group. Patients in the floating needle treatment group received floating needle therapy and placebo. Those in the duloxetine treatment group received duloxetine and simulated floating needle therapy. Those in the placebo treatment group received the placebo and simulated floating needle therapy. All treatment lasted for six weeks. Efficacy and adverse reactions were evaluated using Simple McGill pain scale (SF-MPQ) and Treatment Emergent Symptom Scale (TESS) before treatment and immediately after treatment, as well as at the end of 1st, 2nd, 4th, and 6th week of treatment, respectively. Hamilton Depression Scale (HAMD, 17 items), Hamilton Anxiety Scale (HAMA) were assessed before treatment and at the end of 1st, 2nd, 4th, and 6th week of treatment, respectively. Patients in the floating needle treatment group and the duloxetine treatment group with the total reducing score rate of SF-MPQ in Pain Rating index (PRI) ≥ 50% after 6 weeks' treatment were involved in the follow-up study. (1) Compared with the same group before treatment, SF-MPQ score, HAMD score and HAMA total scores all decreased in all the three groups at the end of 1st, 2nd, 4th, and 6th week of treatment (P floating needle treatment group (P floating needle treatment group significantly decreased after 1, 2, 4, and 6 weeks of treatment (P floating needle treatment group, 17 (50.0%) in the duloxetine treatment group, and 7 (21.2%) in the placebo treatment group. Compared with the placebo treatment group, the incidence of adverse reaction increased in the duloxetine treatment group (χ² = 6.04, P floating needle treatment group (χ² = 14.9, P floating needle treatment group and 17

NEEDLE KNIFE SPHINCTEROTOMY - THE CHRIS HANI BARAGWANATH ACADEMIC HOSPITAL EXPERIENCE.

Science.gov (United States)

Thomson, J T; Smith, M D; Omoshoro-Jones, J A O; Devar, J D; Khan, Z K; Jugmohan, B J

2017-06-01

Deep biliary cannulation is essential in performing a therapeutic ERCP. Cannulation can be enhanced through the utilization of a pre-cut by means of a needle knife sphincterotomy. Retrospective analysis of the Chris Hani Baragwanath Academic Hospital's ERCP database was performed. All ERCPs performed with the aid of a needle knife were identified and analysed for successful and unsuccessful deep biliary cannulation. 2830 ERCPs were performed during the study period. 369 (13%) required needle knife sphincterotomies and successful deep biliary cannulation was achieved in 229 (62%) of these patients. Repeat ERCPs were performed on 125 (34%) patients. 61 (49%) of the repeat ERCPs were performed because of previously failed cannulation. 34 (56%) of these repeat ERCPs resulted in successful deep biliary cannulation at re-attempt. 99% of successful cannulations at repeat ERCP had had a needle knife sphincterotomy at the first ERCP. Needle knife sphincterotomy improves deep biliary cannulation at initial ERCP and subsequent ERCPs with low incidences of complications.

Acupuncture sensation during ultrasound guided acupuncture needling

Science.gov (United States)

Park, Jongbae J.; Akazawa, Margeaux; Ahn, Jaeki; Beckman-Harned, Selena; Lin, Feng-Chang; Lee, Kwangjae; Fine, Jason; Davis, Robert T; Langevin, Helene

2014-01-01

Background Although acupuncture sensation (also known as de qi) is a cornerstone of traditional acupuncture therapy, most research has accepted the traditional method of defining acupuncture sensation only through subjective patient reports rather than on any quantifiable physiological basis. Purpose To preliminarily investigate the frequency of key sensations experienced while needling to specific, quantifiable tissue levels (TLs) guided by ultrasound (US) imaging. Methods Five participants received needling at two acupuncture points and two control points at four TLs. US scans were used to determine when each TL was reached. Each volunteer completed 32 sets of modified Southampton Needle Sensation Questionnaires. Part one of the study tested sensations experienced at each TL and part two compared the effect of oscillation alone versus oscillation + rotation. Results In all volunteers, the frequency of pricking, sharp sensations was significantly greater in shallower TLs than deeper (p=0.007); the frequency of sensations described as deep, dull and heavy, as spreading, and as electric shocks was significantly greater in deeper TLs than shallower (p=0.002). Sensations experienced did not significantly differ between real and control points within each of three TLs (p>0.05) except TL 4 (p=0.006). The introduction of needle rotation significantly increased deep, dull, heavy sensations, but not pricking and sharp sensations; within each level, the spectrum of sensation experienced during both oscillation + rotation and oscillation alone did not significantly differ between acupuncture and control points. Conclusion The preliminary study indicates a strong connection between acupuncture sensation and both tissue depth and needle rotation. Furthermore, the new methodology has been proven feasible. A further study with an objective measurement is warranted. PMID:21642648

Transcription Through The Eye Of A Needle: Daily And Annual Cycles Of Gene Expression Variation In Douglas-Fir Needles

OpenAIRE

Dolan, Peter; Cronn, Richard; Denver, Dee; Clair, J.; Neale, David; Wegrzyn, Jill; Jogdeo, Sanjuro

2017-01-01

Background: Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal rhythms and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii)...

Breakdown characteristics of electro-negative gases under needle-plane gap. Hari-hiraita gap ni okeru denkiteki fusei gas no zetsuen hakai tokusei

Energy Technology Data Exchange (ETDEWEB)

Nakayama, H.; Onoda, M.; Amakawa, K. (Himeji Institute of Technology, Hyogo (Japan)); Kuroda, S. (Nitto Denko Corp., Tokyo (Japan))

1990-07-20

The voltage-time (V-t) characteristics of corona onset and breakdown were examined in electro-negative gases as SF {sub 6} and CCl {sub 2} F {sub 2}, using a needle-plane electrode with small gap and {mu} s square pulse voltage with various wave fronts. The V-t characteristics in electro-neutral gas as N {sub 2} ordinarily descended rightwards, but those in SF {sub 6} descended rightwards only in smaller gaps and lower gas pressures. In the pulse voltage with shorter wave fronts, those in SF {sub 6} also offered a particular shape descending leftwards. The particular shape was dependent on the steepness of the pulse wave front, being strongly affected by shorter wave fronts, and also strongly related to the onset and development length of corona. The particular phenomenon of V-t characteristics was observed more obviously at a positive needle than negative one without any extremely long corona lengths at negative one, indicating a polarity effect. The phenomenon was also observed in CCl {sub 2} F {sub 2} as particular one in electro-negative gases. 21 refs., 12 figs.

Biocompatible 3D printed magnetic micro needles

KAUST Repository

Kavaldzhiev, Mincho

2017-01-30

Biocompatible functional materials play a significant role in drug delivery, tissue engineering and single cell analysis. We utilized 3D printing to produce high aspect ratio polymer resist microneedles on a silicon substrate and functionalized them by iron coating. Two-photon polymerization lithography has been used for printing cylindrical, pyramidal, and conical needles from a drop cast IP-DIP resist. Experiments with cells were conducted with cylindrical microneedles with 630 ± 15 nm in diameter with an aspect ratio of 1:10 and pitch of 12 μm. The needles have been arranged in square shaped arrays with various dimensions. The iron coating of the needles was 120 ± 15 nm thick and has isotropic magnetic behavior. The chemical composition and oxidation state were determined using energy electron loss spectroscopy, revealing a mixture of iron and Fe3O4 clusters. A biocompatibility assessment was performed through fluorescence microscopy using calcein/EthD-1 live/dead assay. The results show a very high biocompatibility of the iron coated needle arrays. This study provides a strategy to obtain electromagnetically functional microneedles that benefit from the flexibility in terms of geometry and shape of 3D printing. Potential applications are in areas like tissue engineering, single cell analysis or drug delivery.

Biocompatible 3D printed magnetic micro needles

KAUST Repository

Kavaldzhiev, Mincho; Perez, Jose E.; Ivanov, Yurii; Bertoncini, Andrea; Liberale, Carlo; Kosel, Jü rgen

2017-01-01

Biocompatible functional materials play a significant role in drug delivery, tissue engineering and single cell analysis. We utilized 3D printing to produce high aspect ratio polymer resist microneedles on a silicon substrate and functionalized them by iron coating. Two-photon polymerization lithography has been used for printing cylindrical, pyramidal, and conical needles from a drop cast IP-DIP resist. Experiments with cells were conducted with cylindrical microneedles with 630 ± 15 nm in diameter with an aspect ratio of 1:10 and pitch of 12 μm. The needles have been arranged in square shaped arrays with various dimensions. The iron coating of the needles was 120 ± 15 nm thick and has isotropic magnetic behavior. The chemical composition and oxidation state were determined using energy electron loss spectroscopy, revealing a mixture of iron and Fe3O4 clusters. A biocompatibility assessment was performed through fluorescence microscopy using calcein/EthD-1 live/dead assay. The results show a very high biocompatibility of the iron coated needle arrays. This study provides a strategy to obtain electromagnetically functional microneedles that benefit from the flexibility in terms of geometry and shape of 3D printing. Potential applications are in areas like tissue engineering, single cell analysis or drug delivery.

[Closed needle-biopsy in the diagnosis of neoplasms].

Science.gov (United States)

Sforza, M; Perelli Ercolini, M; Beani, G

1979-04-01

The AA. demonstrate with this communication the validity of the needle biopsie for the diagnosis of neoplasms. They had used it for the breast, thyroid, flg and some other superficial tumefactions. In the mass-screening for the feminine neoplasms the clinical examination and the needle biopsy are very good method for a careful diagnosis.

Options for reducing HIV transmission related to the dead space in needles and syringes.

Science.gov (United States)

Zule, William A; Pande, Poonam G; Otiashvili, David; Bobashev, Georgiy V; Friedman, Samuel R; Gyarmathy, V Anna; Des Jarlais, Don C

2018-01-15

When shared by people who inject drugs, needles and syringes with different dead space may affect the probability of HIV and hepatitis C virus (HCV) transmission differently. We measured dead space in 56 needle and syringe combinations obtained from needle and syringe programs across 17 countries in Europe and Asia. We also calculated the amounts of blood and HIV that would remain in different combinations following injection and rinsing. Syringe barrel capacities ranged from 0.5 to 20 mL. Needles ranged in length from 8 to 38 mm. The average dead space was 3 μL in low dead space syringes with permanently attached needles, 13 μL in high dead space syringes with low dead space needles, 45 μL in low dead space syringes with high dead space needles, and 99 μL in high dead space syringes with high dead space needles. Among low dead space designs, calculated volumes of blood and HIV viral burden were lowest for low dead space syringes with permanently attached needles and highest for low dead space syringes with high dead space needles. The dead space in different low dead space needle and syringe combinations varied substantially. To reduce HIV transmission related to syringe sharing, needle and syringe programs need to combine this knowledge with the needs of their clients.

High-cycle electromechanical aging of dielectric elastomer actuators with carbon-based electrodes

Science.gov (United States)

de Saint-Aubin, C. A.; Rosset, S.; Schlatter, S.; Shea, H.

2018-07-01

We present high-cycle aging tests of dielectric elastomer actuators (DEAs) based on silicone elastomers, reporting on the time-evolution of actuation strain and of electrode resistance over millions of cycles. We compare several types of carbon-based electrodes, and for the first time show how the choice of electrode has a dramatic influence on DEA aging. An expanding circle DEA configuration is used, consisting of a commercial silicone membrane with the following electrodes: commercial carbon grease applied manually, solvent-diluted carbon grease applied by stamping (pad printing), loose carbon black powder applied manually, carbon black powder suspension applied by inkjet-printing, and conductive silicone-carbon composite applied by stamping. The silicone-based DEAs with manually applied carbon grease electrodes show the shortest lifetime of less than 105 cycles at 5% strain, while the inkjet-printed carbon powder and the stamped silicone-carbon composite make for the most reliable devices, with lifetimes greater than 107 cycles at 5% strain. These results are valid for the specific dielectric and electrode configurations that were tested: using other dielectrics or electrode formulations would lead to different lifetimes and failure modes. We find that aging (as seen in the change in resistance and in actuation strain versus cycle number) is independent of the actuation frequency from 10 Hz to 200 Hz, and depends on the total accumulated time the DEA spends in an actuated state.

NOTE: Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

Science.gov (United States)

Thompson, S. A.; Fung, A. Y. C.; Zaider, M.

2002-08-01

One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results.

Ultrasonography-Guided Fine Needle Aspiration Cytology of Cervical Lymphadenopathy: Comparative Study of the Cytological Adequacy Using of 21- and 23- Gauge Needles

International Nuclear Information System (INIS)

Beak, Jin Wook; KIm, Dong Wook; Kim, Bo Mi

2011-01-01

To assess the difference in the cytological adequacy of ultrasonography (US)-guided fine needle aspiration cytology (US-FNAC) for cervical lymphadenopathy using 21 and 23 gauge needles. US-FNACs were separately performed on two cervical lymph nodes and in each patient using 21 gauge (group A) and 23 gauge (group B) needles, respectively. We used 4 grade classifications for the cytological analysis of each slide and compared the cytological adequacy of US-FNAC for cervical lymphadenopathy in the two groups. We performed US-FNACs on 58 cervical lymph nodes from 29 patients, with a cytological adequacy of 69.0%. The number of adequate cytological results was 19 (65.5%) in group A and 21 (72.4%) in group B, and the diagnostic adequacy did not differ significantly between the two groups (Mann-Whitney test, p = 0.574). There was no statistically significant difference in the cytological adequacy of US-FNAC for cervical lymphadenopathy according using of 21 and 23 gauge needles.

Efficacy of Tuohy Needle in Oocytes Collection from Excised Mare Ovaries

Directory of Open Access Journals (Sweden)

F. Cremonesi

2010-01-01

Full Text Available Two methods have been described to recover oocytes from equine follicles in excised ovaries: aspiration and scraping. Aim of this work was to develop an effective method for collecting equine oocytes using Tuohy needle and comparing this technique to aspiration and scraping, with or without tunica albuginea removal. This hollow hypodermic needle, usually employed for inserting epidural catheters, is designed with a slightly curved tip, shaped similar to a small curette. In unpeeled ovaries, the recovery rates of Tuohy needle group was higher (<.05 than in the 16 g needle aspiration and in the scraped ovaries (57% versus 36% and 47% while the rate of cumulus-intact oocytes was higher than aspiration (46.9% versus 39.36% but lower than scraping (46.97% (<.001. In unpeeled ovaries there was significant difference in maturation rate of oocytes recovered by Tuohy needle in respect to peeled ovaries (58.54% versus 50.17%, resp.. Combination of aspiration and scraping by Tuohy needle allows a faster and reliable collection of oocytes suitable for horse IVM.

MLESAC Based Localization of Needle Insertion Using 2D Ultrasound Images

Science.gov (United States)

Xu, Fei; Gao, Dedong; Wang, Shan; Zhanwen, A.

2018-04-01

In the 2D ultrasound image of ultrasound-guided percutaneous needle insertions, it is difficult to determine the positions of needle axis and tip because of the existence of artifacts and other noises. In this work the speckle is regarded as the noise of an ultrasound image, and a novel algorithm is presented to detect the needle in a 2D ultrasound image. Firstly, the wavelet soft thresholding technique based on BayesShrink rule is used to denoise the speckle of ultrasound image. Secondly, we add Otsu’s thresholding method and morphologic operations to pre-process the ultrasound image. Finally, the localization of the needle is identified and positioned in the 2D ultrasound image based on the maximum likelihood estimation sample consensus (MLESAC) algorithm. The experimental results show that it is valid for estimating the position of needle axis and tip in the ultrasound images with the proposed algorithm. The research work is hopeful to be used in the path planning and robot-assisted needle insertion procedures.

Growth of highly mesoporous CuCo2O4@C core-shell arrays as advanced electrodes for high-performance supercapacitors

Science.gov (United States)

Yan, Hailong; Lu, Yang; Zhu, Kejia; Peng, Tao; Liu, Xianming; Liu, Yunxin; Luo, Yongsong

2018-05-01

A series of CuCo2O4 nanostructures with different morphologies were prepared by a hydrothermal method in combination with thermal treatment. The morphology, structure and composition were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. As the electrode materials for supercapacitors, CuCo2O4 nanoneedles delivered the highest specific capacitance compared with other CuCo2O4 nanostructures. Electrochemical performance measurements demonstrate that the carbon layer can improve the electrochemical stability of CuCo2O4 nanoneedles. The CuCo2O4@C electrode exhibits a high specific capacitance of 1432.4 F g-1 at a current density of 1 A g-1, with capacitance retention of 98.2% after 3000 circles. These characteristics of CuCo2O4@C composite are mainly due to the unique one dimensional needle-liked architecture and the conducting carbon, which provide a faster ion/electron transfer rate. These excellent performances of the CuCo2O4@C electrode confirmed the material as a positive electrode for hybrid supercapacitor application.

[Therapeutic effect observation of chronic knee joint pain assisted with the central-square needling technique of the thumb-tack needles].

Science.gov (United States)

Yang, Yang; Qi, Si; Liu, Mengyue; Zhao, Yu; Li, Ning

2017-10-12

To compare the differences in the clinical therapeutic effects on chronic knee joint pain between the combination of the central-square needling technique of thumb-tack needles with the routine therapy of acupuncture, moxibustion and tuina and the routine therapy of acupuncture, moxibustion and tuina . One hundred and twenty patients of chronic knee joint pain were randomized into an observation group and a control group, 60 cases in each one. In the control group, the routine therapy of acupuncture, moxibustion and tuina was adopted. In the observation group, at the end of treatment with the routine therapy of acupuncture, moxibustion and tuina , the subcutaneous embedding therapy was followed with four thumb-tack needles at the sites 1 to 1.5 cm above, below and bilateral to the main point ( ashi point) separately, and the needles were retained for 24 h to 48 h. The treatment was given once every two days, three times a week, totally 6 times in two weeks; and the follow-up visit was done for 3 months in patients of the two groups. The visual analogue scale (VAS) score before and after each treatment, Lequesne index score before treatment and at the end of follow-up and the case numbers of proactive use of painkillers or receiving acupuncture treatment in the follow-up stage were compared and observed in the patients of the two groups. The VAS score was reduced gradually after treatment in the patients of the two groups. The differences were significant statistically after the second treatment as compared with those before the treatment in the two groups (all P 0.05). In the follow-up stage, there were 0 case in the observation group and 9 cases in the control group in terms of proactive use of painkillers ( P 0.05). The acupuncture scheme in assistance with the central-square needling technique of thumb-tack needles obviously relieves chronic knee joint pain, much better sustains the analgesic effects of acupuncture and improves patient compliance.

Textiles: Some technocal information and data IV: sewability, sewing needles, threads and seams.

CSIR Research Space (South Africa)

Hunter, L

1979-09-01

Full Text Available half in about four c~ro"dd5 - - - - . . - - . Reducing the needle \\docity during its contact with the fabric can reduce needle temocratures bv about 50°C although other workers found the differences ;o be only 5 to IPC14. ~adiation plays a minor..., may have led to the confusion concerning the relative merits of different needle point30. Needle point shape does not appear to significantly affect maximum penetration force or energy~ expended while bulged-eye needles reduce heat build...

Initial experience with new dedicated needles for laparoscopic ultrasound-guided fine-needle aspiration and histological biopsies

DEFF Research Database (Denmark)

Mortensen, M B; Durup, J; Pless, T

2001-01-01

BACKGROUND AND STUDY AIMS: Laparoscopic ultrasonography (LUS) is an important imaging modality during laparoscopic staging of intra-abdominal malignancies, but LUS-assisted biopsy is often difficult or impossible. We report a newly developed inbuilt biopsy system for direct LUS-guided fine......-needle aspiration (FNA) and Tru-cut biopsies. PATIENTS AND METHODS: LUS-guided biopsy was performed in 20 patients with upper gastrointestinal tract tumors. The biopsied lesions had either not been previously detected by other imaging modalities or had been inaccessible, or the biopsy sample had been inadequate...... were good or acceptable in 18 patients (90%). Slight needle deviation (material was obtained, but pathological examination was impossible owing...

[Sleep disorder of schizophrenia treated with shallow needling: a randomized controlled trial].

Science.gov (United States)

Huang, Yanxi; Zheng, Ying

2015-09-01

To compare the clinical effective differences between shallow needling and medication for the sleep disorder of schizophrenia. Ninety-six patients with the sleep disorder of schizophrenia were randomly divided into a shallow needling group and a medication group, 48 cases in each one (one case dropping in the shallow needling group and two cases dropping in the medication group). The same dose paliperidone tablets were adopted in the two groups. In the shallow needling group, the main acupoints were Baihui (GV 20), Shangenxue (Extra) and Ezhongxian (MS 1), and the acupoints based on syndrome differentiation were selected. The shallow needling manipulation was used once a day, 5 times a week. In the medication group, 3 mg eszopiclone tablets were prescribed orally before sleep once every night. The patients were treated for 6 weeks in the two groups. Sleep condition was evaluated by Pittsburgh sleep quality index (PSQI) before and after treatment, and the clinical efficacy and the adverse reaction were assessed by positive and negative symptoms scale (PANSS) and treatment emergent symptom scale (TESS) before and after 2-week, 4-week and 6-week treatment. The clinical effects between the two groups were compared. After treatment in the two groups, both the total scores and the each factor score of the PSQI and the PANSS were apparently decreased (Pshallow needling group was reduced more obviously than that of the medication group (Pshallow needling group (Pshallow needling group was better than that in the medication group after treatment (Pshallow needling group after treatment (P0. 05). At the end of the 6th week, the curative and effective rate was 63. 9% (30/47) and the total effective rate was 95. 8% (45/47) in the shallow needling group;the curative and effective rate was 58. 7% (27/46) and the total effective rate was 91. 3% (42/46) in the medication group. The difference of the effect was not statistically significant between the two groups (P>0. 05). The

A comparison of epicuticular wax of Pinus sylvestris needles from three sites in Ireland

International Nuclear Information System (INIS)

Donnelly, A.; Dowding, P.

1994-01-01

Three forest stands of Pinus sylvestris were chosen for comparison in Ireland. Needles from three year classes were collected. Cuticular transpiration curves showed that the rate of water loss from 1-year-old needles was faster than either 2-year-old or current-year needles at all sites. The amount of epicuticular wax extracted was similar to that reported in the literature. Needle wettability increased with needle age. Amorphous wax coverage was estimated using scanning electron microscopy (SEM) and was found to increase with needle age. Algal cells were noted on needles of all ages at one site and appeared to affect transpiration and microroughness. The presence of fungal hyphae was also noted. (orig.)

EUS-Guided Needle-Based Confocal Laser Endomicroscopy

DEFF Research Database (Denmark)

Bhutani, Manoop S; Koduru, Pramoda; Joshi, Virendra

2015-01-01

Endoscopic ultrasound (EUS) has emerged as an excellent tool for imaging the gastrointestinal tract, as well as surrounding structures. EUS-guided fine-needle aspiration (EUS-FNA) has become the standard of care for the tissue sampling of a variety of masses and lymph nodes within and around...... the gut, providing further diagnostic and staging information. Confocal laser endomicroscopy (CLE) is a novel endoscopic method that enables imaging at a subcellular level of resolution during endoscopy, allowing up to 1000-fold magnification of tissue and providing an optical biopsy. A new procedure...... that has been developed in the past few years is needle-based confocal laser endomicroscopy (nCLE), which involves a mini-CLE probe that can be passed through a 1 9-gauge needle during EUS-FNA. This enables the real-time visualization of tissue at a microscopic level, with the potential to further improve...

Achievement of needle-like focus by engineering radial-variant vector fields.

Science.gov (United States)

Gu, Bing; Wu, Jia-Lu; Pan, Yang; Cui, Yiping

2013-12-16

We present and demonstrate a novel method for engineering the radial-variant polarization on the incident field to achieve a needle of transversally polarized field without any pupil filters. We generate a new kind of localized linearly-polarized vector fields with distributions of states of polarization (SoPs) describing by the radius to the power p and explore its tight focusing, nonparaxial focusing, and paraxial focusing properties. By tuning the power p, we obtain the needle-like focal field with hybrid SoPs and give the formula for describing the length of the needle. Experimentally, we systematically investigate both the intensity distributions and the polarization evolution of the optical needle by paraxial focusing the generated vector field. Such an optical needle, which enhances the light-matter interaction, has intriguing applications in optical microma-chining and nonlinear optics.

Knowledge, attitude and practices about needle stick injuries in health care workers

International Nuclear Information System (INIS)

Waqar, S.H.; Siraj, M.U.; Razzaq, Z.; Malik, Z.I.; Zahid, M.A.

2011-01-01

Objectives: To assess knowledge, attitude and practices about needle stick Injuries in health care workers. Study type, settings and duration: Hospital based study carried out at Pakistan Institute of Medical Sciences, Islamabad, from August 2010 to November 2010. Subjects and Methods: A self administered 19 items questionnaire was prepared which contained information about needle stick injuries, its awareness, frequency of injury and the protocols that were followed after an injury had occurred. These questionnaires were given to 500 health care workers working in different wards and theaters of the hospital after obtaining their informed written consent. The health care workers included doctors, nurses and paramedical staff of Pakistan Institute of Medical Sciences, Islamabad. The data was entered and analyzed using SPSS version 15. Results: A total of 500 health care workers filled the questionnaire and returned it. Out of these 416(83.2%) reported ever experiencing needle stick injuries in their professional life. Health care workers working in Emergency department were most frequently affected (65%) followed by those working in different wards (27%) and operation theatre (8%). Most (93.6%) workers had knowledge about needle stick injuries and only 6.4% were not aware of it. Needle stick injury occurred from a brand new (unused) syringe in 51.2% cases, while in 32.8% cases, the needle caused an injury after it had been used for an injection. In 5% cases, injury occurred with blood stained needles. The commonest reasons for needle injury in stick injuries were heavy work load (36.8%) followed by hasty work (33.6%) and needle recapping (18.6%). About 66% health care workers were already vaccinated against hepatitis B. Only 13% workers followed universal guidelines of needle stick injuries and no case was reported to hospital authorities. Conclusions: Health care workers had inadequate knowledge about the risk associated with needle stick injuries and do not

Evaluating the advances and use of hypodermic needles in dentistry.

Science.gov (United States)

Boynes, Sean G

2014-10-01

Different injection techniques and patient management methodologies have been proposed to decrease the fear patients may have concerning dental needles. Dental providers should have an understanding of the technological advances, changes in techniques, and patient perceptions associated with the hypodermic needle. This article provides an overview of the pain perception process associated with dental injections. It reviews the two main sensory nerve fibers associated with injection pain and discusses needle properties as well as complications and adverse occurrences.

Development of Needle Insertion Manipulator for Central Venous Catheterization

Science.gov (United States)

Kobayashi, Yo; Hong, Jaesung; Hamano, Ryutaro; Hashizume, Makoto; Okada, Kaoru; Fujie, Masakatsu G.

Central venous catheterization is a procedure, which a doctor insert a catheter into the patient’s vein for transfusion. Since there are risks of bleeding from arterial puncture or pneumothorax from pleural puncture. Physicians are strictly required to make needle reach up into the vein and to stop the needle in the middle of vein. We proposed a robot system for assisting the venous puncture, which can relieve the difficulties in conventional procedure, and the risks of complication. This paper reports the design structuring and experimental results of needle insertion manipulator. First, we investigated the relationship between insertion force and angle into the vein. The results indicated that the judgment of perforation using the reaction force is possible in case where the needling angle is from 10 to 20 degree. The experiment to evaluate accuracy of the robot also revealed that it has beyond 0.5 mm accuracy. We also evaluated the positioning accuracy in the ultrasound images. The results displays that the accuracy is beyond 1.0 mm and it has enough for venous puncture. We also carried out the venous puncture experiment to the phantom and confirm our manipulator realized to make needle reach up into the vein.

Patients’ Knowledge of and Practices Relating to the Disposal of Used Insulin Needles

Directory of Open Access Journals (Sweden)

Kerri T. Musselman, PharmD

2010-01-01

Full Text Available Objective: To determine (1 how patients currently dispose of used insulin needles, (2 whether patients were educated about disposal of their used insulin needles, and (3 who educated patients about the disposal of their used insulin needles.Methods: A self-administered questionnaire was designed for this study. The survey assessed patient knowledge about disposal of used insulin needles and the patient-reported source and location of education about disposal techniques. The questionnaire was administered to a convenience sample of patients from four locations in Richmond, Virginia. Any patient who used insulin, was at least 18 years old, and was willing to complete the survey was eligible for inclusion.Results: Fifty responses were received with 40% indicating that education had been received on the disposal of used needles. From that 40%, nurses were identified as the source of education 60% of the time and pharmacists 25% of the time. Approximately 50% of the respondents reported disposing of used needles directly in the trash when at home. While away from home, 22% reported placing used needles in the trash, and 38% took them home for disposal.Conclusion: Patients are not consistently educated regarding the proper disposal of used needles. Health care practitioners should play a larger role in educating patients about the potential risks of inappropriate needle disposal and appropriate disposal methods. Future research is still needed to understand fully the magnitude of the problems associated with inappropriate needle disposal by patients.

Teleoperation of steerable flexible needles by combining kinesthetic and vibratory feedback.

Science.gov (United States)

Pacchierotti, Claudio; Abayazid, Momen; Misra, Sarthak; Prattichizzo, Domenico

2014-01-01

Needle insertion in soft-tissue is a minimally invasive surgical procedure that demands high accuracy. In this respect, robotic systems with autonomous control algorithms have been exploited as the main tool to achieve high accuracy and reliability. However, for reasons of safety and responsibility, autonomous robotic control is often not desirable. Therefore, it is necessary to focus also on techniques enabling clinicians to directly control the motion of the surgical tools. In this work, we address that challenge and present a novel teleoperated robotic system able to steer flexible needles. The proposed system tracks the position of the needle using an ultrasound imaging system and computes needle's ideal position and orientation to reach a given target. The master haptic interface then provides the clinician with mixed kinesthetic-vibratory navigation cues to guide the needle toward the computed ideal position and orientation. Twenty participants carried out an experiment of teleoperated needle insertion into a soft-tissue phantom, considering four different experimental conditions. Participants were provided with either mixed kinesthetic-vibratory feedback or mixed kinesthetic-visual feedback. Moreover, we considered two different ways of computing ideal position and orientation of the needle: with or without set-points. Vibratory feedback was found more effective than visual feedback in conveying navigation cues, with a mean targeting error of 0.72 mm when using set-points, and of 1.10 mm without set-points.

Electrospun fibrous electrodes with tunable microstructure made of polyaniline/multi-walled carbon nanotube suspension for all-solid-state supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Liang, Junsheng; Su, Shijie; Fang, Xu [Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116023 (China); Wang, Dazhi, E-mail: d.wang@dlut.edu.cn [Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116023 (China); Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116023 (China); Xu, Shuangchao [Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116023 (China)

2016-09-15

Highlights: • Electrospun PANI/MWCNT fibrous electrodes for supercapacitor were prepared. • Microstructure of electrodes is tunable by changing the electrospin parameters. • Fiber-diameter dependence of the electrode performance was observed. • High performance and good stability of electrospun electrodes were obtained. - Abstract: Electrospinning technique was used to prepare high performance fibrous electrodes with tunable microstructure for all-solid-state electrochemical supercapacitor. Symmetrically sandwiched supercapacitors consisting of flexible electrospun polyaniline (PANI)/multi-walled carbon nanotube (MWCNT) electrodes and polyvinyl alcohol (PVA)/sulfuric acid (H{sub 2}SO{sub 4}) gel electrolyte were assembled. Tunable microstructure of the fibrous electrode was obtained by changing the electrospinning parameters including the collector–needle distance (CND) and the suspension flow rate (SFR). Results show that, higher CND combining with lower SFR can result in a smaller average diameter of the electrospun fibers and hence improve the electrode performance. When the CND changes from 80 to 140 mm, the average fiber diameter will decrease from 2.89 to 1.21 μm, and the specific surface area of the electrode can increase from 57 to 83 m{sup 2}·g{sup −1}. The corresponding specific capacitance of the electrospun electrode will therefore increase from 129.5 to 180 F·g{sup −1}, leading to a synchronous improvement of the energy density of the supercapacitor from 18 to 25 Wh·kg{sup −1}. On the other hand, the supercapacitors using fibrous electrodes in this work also show good rate capability and cycling stability. Using the electrode with an average fiber diameter of 1.21 μm, the specific capacitances can maintain 131 F·g{sup −1} at a current density of 4 A·g{sup −1}, which is 73% of the specific capacitance of the same sample at a current density of 0.5 A·g{sup −1}. And the specific capacitance of the electrode can retain 89

Electrospun fibrous electrodes with tunable microstructure made of polyaniline/multi-walled carbon nanotube suspension for all-solid-state supercapacitors

International Nuclear Information System (INIS)

Liang, Junsheng; Su, Shijie; Fang, Xu; Wang, Dazhi; Xu, Shuangchao

2016-01-01

Highlights: • Electrospun PANI/MWCNT fibrous electrodes for supercapacitor were prepared. • Microstructure of electrodes is tunable by changing the electrospin parameters. • Fiber-diameter dependence of the electrode performance was observed. • High performance and good stability of electrospun electrodes were obtained. - Abstract: Electrospinning technique was used to prepare high performance fibrous electrodes with tunable microstructure for all-solid-state electrochemical supercapacitor. Symmetrically sandwiched supercapacitors consisting of flexible electrospun polyaniline (PANI)/multi-walled carbon nanotube (MWCNT) electrodes and polyvinyl alcohol (PVA)/sulfuric acid (H_2SO_4) gel electrolyte were assembled. Tunable microstructure of the fibrous electrode was obtained by changing the electrospinning parameters including the collector–needle distance (CND) and the suspension flow rate (SFR). Results show that, higher CND combining with lower SFR can result in a smaller average diameter of the electrospun fibers and hence improve the electrode performance. When the CND changes from 80 to 140 mm, the average fiber diameter will decrease from 2.89 to 1.21 μm, and the specific surface area of the electrode can increase from 57 to 83 m"2·g"−"1. The corresponding specific capacitance of the electrospun electrode will therefore increase from 129.5 to 180 F·g"−"1, leading to a synchronous improvement of the energy density of the supercapacitor from 18 to 25 Wh·kg"−"1. On the other hand, the supercapacitors using fibrous electrodes in this work also show good rate capability and cycling stability. Using the electrode with an average fiber diameter of 1.21 μm, the specific capacitances can maintain 131 F·g"−"1 at a current density of 4 A·g"−"1, which is 73% of the specific capacitance of the same sample at a current density of 0.5 A·g"−"1. And the specific capacitance of the electrode can retain 89% after 1500 charge/discharge cycles.

Robotic Needle Guide for Prostate Brachytherapy: Clinical Testing of Feasibility and Performance

Science.gov (United States)

Song, Danny Y; Burdette, Everette C; Fiene, Jonathan; Armour, Elwood; Kronreif, Gernot; Deguet, Anton; Zhang, Zhe; Iordachita, Iulian; Fichtinger, Gabor; Kazanzides, Peter

2010-01-01

Purpose Optimization of prostate brachytherapy is constrained by tissue deflection of needles and fixed spacing of template holes. We developed and clinically tested a robotic guide towards the goal of allowing greater freedom of needle placement. Methods and Materials The robot consists of a small tubular needle guide attached to a robotically controlled arm. The apparatus is mounted and calibrated to operate in the same coordinate frame as a standard template. Translation in x and y directions over the perineum ±40mm are possible. Needle insertion is performed manually. Results Five patients were treated in an IRB-approved study. Confirmatory measurements of robotic movements for initial 3 patients using infrared tracking showed mean error of 0.489 mm (SD 0.328 mm). Fine adjustments in needle positioning were possible when tissue deflection was encountered; adjustments were performed in 54/179 (30.2%) needles placed, with 36/179 (20.1%) adjustments of > 2mm. Twenty-seven insertions were intentionally altered to positions between the standard template grid to improve the dosimetric plan or avoid structures such as pubic bone and blood vessels. Conclusions Robotic needle positioning provided a means of compensating for needle deflections as well as the ability to intentionally place needles into areas between the standard template holes. To our knowledge, these results represent the first clinical testing of such a system. Future work will be incorporation of direct control of the robot by the physician, adding software algorithms to help avoid robot collisions with the ultrasound, and testing the angulation capability in the clinical setting. PMID:20729152

Study on design and cutting parameters of rotating needles for core biopsy.

Science.gov (United States)

Giovannini, Marco; Ren, Huaqing; Cao, Jian; Ehmann, Kornel

2018-06-15

Core needle biopsies are widely adopted medical procedures that consist in the removal of biological tissue to better identify a lesion or an abnormality observed through a physical exam or a radiology scan. These procedures can provide significantly more information than most medical tests and they are usually performed on bone lesions, breast masses, lymph nodes and the prostate. The quality of the samples mainly depends on the forces exerted by the needle during the cutting process. The reduction of these forces is critical to extract high-quality tissue samples. The most critical factors that affect the cutting forces are the geometry of the needle tip and its motion while it is penetrating the tissue. However, optimal needle tip configurations and cutting parameters are not well established for rotating insertions. In this paper, the geometry and cutting forces of hollow needles are investigated. The fundamental goal of this study is to provide a series of guidelines for clinicians and surgeons to properly select the optimal tip geometries and speeds. Analytical models related to the cutting angles of several needle tip designs are presented and compared. Several needle tip geometries were manufactured from a 14-gauge cannula, commonly adopted during breast biopsies. The needles were then tested at different speeds and on different phantom tissues. According to these experimental measurements recommendations were formulated for rotating needle insertions. The findings of this study can be applied and extended to several biopsy procedures in which a cannula is used to extract tissue samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

Spinal anaesthesia in young patients: evaluation of needle gauge ...

African Journals Online (AJOL)

Background:The well-known complication of spinal anaesthesia, postdural puncture headache (PDPH), is especially troublesome in young patients. The needle gauge and configuration of needle tip appear to be the important factors in reducing the incidence of PDPH; however it may increase the incidence of technical ...

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.

A novel fabrication method of silicon nano-needles using MEMS TMAH etching techniques

International Nuclear Information System (INIS)

Yan Sheping; Xu Yang; Yang Junyi; Wang Huiquan; Jin Zhonghe; Wang Yuelin

2011-01-01

Nano-needles play important roles in nanoscale operations. However, current nano-needle fabrication is usually expensive and controling the sizes and angles is complicated. We have developed a simple and low cost silicon nano-needle fabrication method using traditional microelectromechanical system (MEMS) tetramethyl ammonium hydroxide (TMAH) etching techniques. We take advantage of the fact that the decrease of the silicon etch rate in TMAH solutions exhibits an inverse fourth power dependence on the boron doping concentration in our nano-needle fabrication. Silicon nano-needles, with high aspect ratio and sharp angles θ as small as 2.9 deg., are obtained, which could be used for bio-sensors and nano-handling procedures, such as penetrating living cells. An analytic model is proposed to explain the etching evolution of the experimental results, which is used to predict the needle angle, length, and etching time. Based on our method, nano-needles with small acute angle θ can be obtained.

Lumbar punction: comparison between an atraumatic and a traumatic punction needle

Directory of Open Access Journals (Sweden)

Tina Bregant

2017-03-01

Full Text Available Background: Lumbar puncture is a standardized, routine diagnostic procedure in the diagnosis of neurological diseases. Post-duarl puncture headache (PDPH is a common complication which occurs in 10 to 30 % of patients. Although the incidence of PDPH is much lower with the use of small, non-cutting needles, neurologists in Slovenia routinely use the classical traumatic spinal needles.Methods: In the article we provide an overview of a research concerned with the use of traumatic and atraumatic needles in the procedure with the emphasis on complications of the lumbar puncture. We present American and European recommendations for lumbar puncture procedure.Conclusions: International recommendations for neurologists advise the use of atraumatic spinal needles for lumbar puncture. We recommend to Slovenian neurologists to start using the atraumatic needles for elective lumbar punctures and hence provide neurological patients with better quality and cheaper long-term care.

Prevalence of Needle Stick Injuries among Healthcare Workers in ...

African Journals Online (AJOL)

Background: Needle stick injuries represent one of the most important occupational hazards to which health workers are exposed. These injuries result from accidental piercing of the skin and or mucous membranes by sharp objects. Needle stick injuries carry the risk of exposure to blood-borne pathogens, especially ...

Diagnosis Of Thyroid Enlargement: Use Of Fine Needle Aspiration ...

African Journals Online (AJOL)

One hundred and ten Fine Needle Aspiration Biopsies (FNAC) obtained from 87 patients with thyroid enlargement or nodules were retrospectively reviewed. Aspiration biopsy was accomplished using 21-gauge needle attached with 20-ml plastic syringe. There were 14 males and 73 females involved in the study. Sixty- four ...

Automatic Multiple-Needle Surgical Planning of Robotic-Assisted Microwave Coagulation in Large Liver Tumor Therapy.

Directory of Open Access Journals (Sweden)

Shaoli Liu

Full Text Available The "robotic-assisted liver tumor coagulation therapy" (RALTCT system is a promising candidate for large liver tumor treatment in terms of accuracy and speed. A prerequisite for effective therapy is accurate surgical planning. However, it is difficult for the surgeon to perform surgical planning manually due to the difficulties associated with robot-assisted large liver tumor therapy. These main difficulties include the following aspects: (1 multiple needles are needed to destroy the entire tumor, (2 the insertion trajectories of the needles should avoid the ribs, blood vessels, and other tissues and organs in the abdominal cavity, (3 the placement of multiple needles should avoid interference with each other, (4 an inserted needle will cause some deformation of liver, which will result in changes in subsequently inserted needles' operating environment, and (5 the multiple needle-insertion trajectories should be consistent with the needle-driven robot's movement characteristics. Thus, an effective multiple-needle surgical planning procedure is needed. To overcome these problems, we present an automatic multiple-needle surgical planning of optimal insertion trajectories to the targets, based on a mathematical description of all relevant structure surfaces. The method determines the analytical expression of boundaries of every needle "collision-free reachable workspace" (CFRW, which are the feasible insertion zones based on several constraints. Then, the optimal needle insertion trajectory within the optimization criteria will be chosen in the needle CFRW automatically. Also, the results can be visualized with our navigation system. In the simulation experiment, three needle-insertion trajectories were obtained successfully. In the in vitro experiment, the robot successfully achieved insertion of multiple needles. The proposed automatic multiple-needle surgical planning can improve the efficiency and safety of robot-assisted large liver tumor

Automatic Multiple-Needle Surgical Planning of Robotic-Assisted Microwave Coagulation in Large Liver Tumor Therapy.

Science.gov (United States)

Liu, Shaoli; Xia, Zeyang; Liu, Jianhua; Xu, Jing; Ren, He; Lu, Tong; Yang, Xiangdong

2016-01-01

The "robotic-assisted liver tumor coagulation therapy" (RALTCT) system is a promising candidate for large liver tumor treatment in terms of accuracy and speed. A prerequisite for effective therapy is accurate surgical planning. However, it is difficult for the surgeon to perform surgical planning manually due to the difficulties associated with robot-assisted large liver tumor therapy. These main difficulties include the following aspects: (1) multiple needles are needed to destroy the entire tumor, (2) the insertion trajectories of the needles should avoid the ribs, blood vessels, and other tissues and organs in the abdominal cavity, (3) the placement of multiple needles should avoid interference with each other, (4) an inserted needle will cause some deformation of liver, which will result in changes in subsequently inserted needles' operating environment, and (5) the multiple needle-insertion trajectories should be consistent with the needle-driven robot's movement characteristics. Thus, an effective multiple-needle surgical planning procedure is needed. To overcome these problems, we present an automatic multiple-needle surgical planning of optimal insertion trajectories to the targets, based on a mathematical description of all relevant structure surfaces. The method determines the analytical expression of boundaries of every needle "collision-free reachable workspace" (CFRW), which are the feasible insertion zones based on several constraints. Then, the optimal needle insertion trajectory within the optimization criteria will be chosen in the needle CFRW automatically. Also, the results can be visualized with our navigation system. In the simulation experiment, three needle-insertion trajectories were obtained successfully. In the in vitro experiment, the robot successfully achieved insertion of multiple needles. The proposed automatic multiple-needle surgical planning can improve the efficiency and safety of robot-assisted large liver tumor therapy

Needle Biopsy of the Lung

Science.gov (United States)

... clip. The needle is hollow so it can capture the tissue specimen. There are several types of ... breath, difficulty in catching your breath, rapid pulse (heart rate), sharp chest or shoulder pain with breathing, ...

Assessment of bone biopsy needles for sample size, specimen quality and ease of use

International Nuclear Information System (INIS)

Roberts, C.C.; Liu, P.T.; Morrison, W.B.; Leslie, K.O.; Carrino, J.A.; Lozevski, J.L.

2005-01-01

To assess whether there are significant differences in ease of use and quality of samples among several bone biopsy needles currently available. Eight commonly used, commercially available bone biopsy needles of different gauges were evaluated. Each needle was used to obtain five consecutive samples from a lamb lumbar pedicle. Subjective assessment of ease of needle use, ease of sample removal from the needle and sample quality, before and after fixation, was graded on a 5-point scale. The number of attempts necessary to reach a 1 cm depth was recorded. Each biopsy specimen was measured in the gross state and after fixation. The RADI Bonopty 15 g and Kendall Monoject J-type 11 g needles were rated the easiest to use, while the Parallax Core-Assure 11 g and the Bard Ostycut 16 g were rated the most difficult. Parallax Core-Assure and Kendall Monoject needles had the highest quality specimen in the gross state; Cook Elson/Ackerman 14 g and Bard Ostycut 16 g needles yielded the lowest. The MD Tech without Trap-Lok 11 g needle had the highest quality core after fixation, while the Bard Ostycut 16 g had the lowest. There was a significant difference in pre-fixation sample length between needles (P<0.0001), despite acquiring all cores to a standard 1 cm depth. Core length and width decrease in size by an average of 28% and 42% after fixation. Bone biopsy needles vary significantly in performance. Detailed knowledge of the strengths and weaknesses of different needles is important to make an appropriate selection for each individual's practice. (orig.)

Percutaneous image-guided needle biopsy in children - summary of our experience with 57 children

International Nuclear Information System (INIS)

Sklair-Levy, M.; Lebensart, P.D.; Applbaum, Y.H.; Bar-Ziv, J.; Libson, E.; Ramu, N.; Freeman, A.; Gozal, D.; Gross, E.; Sherman, Y.

2001-01-01

Background: Percutaneous image-guided needle biopsy in children has been slower to gain acceptance than in adults where it is regarded as the standard clinical practice in screening suspicious masses. Objectives: To report our experience with percutaneous image-guided needle biopsy in the pediatric population and assess its clinical use, efficacy and limitations. Material and methods: Sixty-nine percutaneous image-guided needle biopsies were performed in 57 children. The age of the children ranged from 4 days to 14 years (mean 5.6 years). We used 16- to-20-gauge cutting-edge needles. Sixty-two biopsies were core-needle biopsies and 7 fine-needle aspiration biopsies. Results: There were 50 malignant lesions, 10 benign lesions and 2 infectious lesions. In 55 (88.7 %) lesions the needle biopsy was diagnostic. In 7 (11.3 %) the biopsy was non-diagnostic and the diagnosis was made by surgery. Core-needle biopsy was diagnostic in 47 of 50 (94 %) of the malignant solid tumors. In 3 out of 5 children with lymphoma, an accurate diagnosis was obtained with needle aspiration. Seven children underwent a repeated core-needle biopsy, (5 for Wilms' tumor and 2 for neuroblastoma) that was diagnostic in all cases. All the biopsies were performed without complications. Conclusion: Percutaneous image-guided needle biopsy is a simple, minimally invasive, safe and accurate method for the evaluation of children with suspicious masses. These data suggest that image-guided needle biopsy is an excellent tool for diagnosing solid tumors in the pediatric population. Negative studies should be considered nondiagnostic and followed by excisional surgical biopsies when clinical suspicion of malignancy is high. (orig.)

Fiber Bragg gratings-based sensing for real-time needle tracking during MR-guided brachytherapy

Energy Technology Data Exchange (ETDEWEB)

Borot de Battisti, Maxence, E-mail: M.E.P.Borot@umcutrecht.nl; Maenhout, Metha; Lagendijk, Jan J. W.; Vulpen, Marco van; Moerland, Marinus A. [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584 CX (Netherlands); Denis de Senneville, Baudouin [Imaging Division, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584 CX, The Netherlands and IMB, UMR 5251 CNRS/University of Bordeaux, Talence 33400 (France); Hautvast, Gilion; Binnekamp, Dirk [Philips Group Innovation Biomedical Systems, Eindhoven 5656 AE (Netherlands)

2016-10-15

Purpose: The development of MR-guided high dose rate (HDR) brachytherapy is under investigation due to the excellent tumor and organs at risk visualization of MRI. However, MR-based localization of needles (including catheters or tubes) has inherently a low update rate and the required image interpretation can be hampered by signal voids arising from blood vessels or calcifications limiting the precision of the needle guidance and reconstruction. In this paper, a new needle tracking prototype is investigated using fiber Bragg gratings (FBG)-based sensing: this prototype involves a MR-compatible stylet composed of three optic fibers with nine sets of embedded FBG sensors each. This stylet can be inserted into brachytherapy needles and allows a fast measurement of the needle deflection. This study aims to assess the potential of FBG-based sensing for real-time needle (including catheter or tube) tracking during MR-guided intervention. Methods: First, the MR compatibility of FBG-based sensing and its accuracy was evaluated. Different known needle deflections were measured using FBG-based sensing during simultaneous MR-imaging. Then, a needle tracking procedure using FBG-based sensing was proposed. This procedure involved a MR-based calibration of the FBG-based system performed prior to the interventional procedure. The needle tracking system was assessed in an experiment with a moving phantom during MR imaging. The FBG-based system was quantified by comparing the gold-standard shapes, the shape manually segmented on MRI and the FBG-based measurements. Results: The evaluation of the MR compatibility of FBG-based sensing and its accuracy shows that the needle deflection could be measured with an accuracy of 0.27 mm on average. Besides, the FBG-based measurements were comparable to the uncertainty of MR-based measurements estimated at half the voxel size in the MR image. Finally, the mean(standard deviation) Euclidean distance between MR- and FBG-based needle position

Accumulation of Cs 137 by needles of pinus silvestris in various types of forest

International Nuclear Information System (INIS)

Golushko, R.M.

2002-01-01

It is researched accumulation of Cs 137 by needles of pine trees during growing old. It is shown, that needles of the one year old have more high radioactivity than needles of the two or three years old. Needles of pine trees accumulated more Cs 137 on good wet soils

Fertilization Changes Chemical Defense in Needles of Mature Norway Spruce (Picea abies

Directory of Open Access Journals (Sweden)

Line Nybakken

2018-06-01

Full Text Available Nitrogen availability limits growth in most boreal forests. However, parts of the boreal zone receive significant levels of nitrogen deposition. At the same time, forests are fertilized to increase volume growth and carbon sequestration. No matter the source, increasing nitrogen in the boreal forest ecosystem will influence the resource situation for its primary producers, the plants, with possible implications for their defensive chemistry. In general, fertilization reduces phenolic compound concentrations in trees, but existing evidence mainly comes from studies on young plants. Given the role of the phenolic compounds in protection against herbivores and other forest pests, it is important to know if phenolics are reduced with fertilization also in mature trees. The evergreen Norway spruce is long-lived, and it is reasonable that defensive strategies could change from the juvenile to the reproductive and mature phases. In addition, as the needles are kept for several years, defense could also change with needle age. We sampled current and previous year needles from an N fertilization experiment in a Norway spruce forest landscape in south-central Norway to which N had been added annually for 13 years. We analyzed total nitrogen (N and carbon (C, as well as low-molecular phenolics and condensed tannins. Needles from fertilized trees had higher N than those from controls plots, and fertilization decreased concentrations of many flavonoids, as well as condensed tannins in current year needles. In previous year needles, some stilbenes and condensed tannins were higher in fertilized trees. In control trees, the total phenolic concentration was almost five times as high in previous year needles compared with those from the current year, and there were great compositional differences. Previous year needles contained highest concentrations of acetophenone and stilbenes, while in the current year needles the flavonoids, and especially coumaroyl

Comparison of Fine Needle Aspiration and Fine Needle Nonaspiration Cytology of Thyroid Nodules: A Meta-Analysis

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Hongming Song

2015-01-01

Full Text Available 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, Web of Science, Google Scholar, EBSCO, OALib, and the Cochrane Library databases. The following search terms were used: fine needle, aspiration, capillary, nonaspiration, sampling without aspiration, thyroid, and cytology. The last search was performed on February 1, 2015. Results. Sixteen studies comprising 1,842 patients and 2,221 samples were included in this study. No statistically significant difference was observed between FNAC and FNNAC groups with respect to diagnostically inadequate smears, diagnostically superior smears, diagnostic performance (accuracy, sensitivity, specificity, negative predictive value, and positive predictive value, area under the summary receiver operating characteristic curve, average score of each parameter (background blood or clot, amount of cellular material, degree of cellular degeneration, degree of cellular trauma, and retention of appropriate architecture, and total score of five parameters. Conclusion. FNAC and FNNAC are equally useful in assessing thyroid nodules.

Fabrication and optical characterization of cadmium sulfide needles using nuclear track membrane

International Nuclear Information System (INIS)

Peng, L.Q.; Wang, S.C.; Ju, X.; Xiao, H.; Chen, H.; He, Y.J.

1999-01-01

Cadmium sulfide needles with a diameter of 0.2 μm have been fabricated in nuclear track polyethylene-terephthalate (PET) membrane by electrochemically depositing from organic solvent dimethylsulfoxide (DMSO) containing CdCl 2 and elemental sulfur at the temperature 110 deg. C. The characterization of the sample of CdS needles was studied by scanning electron microscope, X-ray diffraction, absorption and photoluminescence spectra. The optical experiments show that in the sample of CdS needles there is an absorption peak that could be assigned to the interface states of the CdS needles

Fabrication and optical characterization of cadmium sulfide needles using nuclear track membrane

Energy Technology Data Exchange (ETDEWEB)

Peng, L.Q.; Wang, S.C.; Ju, X.; Xiao, H.; Chen, H.; He, Y.J

1999-06-01

Cadmium sulfide needles with a diameter of 0.2 {mu}m have been fabricated in nuclear track polyethylene-terephthalate (PET) membrane by electrochemically depositing from organic solvent dimethylsulfoxide (DMSO) containing CdCl{sub 2} and elemental sulfur at the temperature 110 deg. C. The characterization of the sample of CdS needles was studied by scanning electron microscope, X-ray diffraction, absorption and photoluminescence spectra. The optical experiments show that in the sample of CdS needles there is an absorption peak that could be assigned to the interface states of the CdS needles.

Diagnostic study of multiple double layer formation in expanding RF plasma

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Chakraborty, Shamik; Paul, Manash Kumar; Roy, Jitendra Nath; Nath, Aparna

2018-03-01

Intensely luminous double layers develop and then expand in size in a visibly glowing RF discharge produced using a plasma source consisting of a semi-transparent cylindrical mesh with a central electrode, in a linear plasma chamber. Although RF discharge is known to be independent of device geometry in the absence of magnetic field, the initiation of RF discharge using such a plasma source results in electron drift and further expansion of the plasma in the vessel. The dynamics of complex plasma structures are studied through electric probe diagnostics in the expanding RF plasma. The measurements made to study the parametric dependence of evolution of double layer structures are analyzed and presented here. The plasma parameter measurements suggest that the complex potential structures initially form with low potential difference between the layers and then gradually expand producing burst oscillations. The present study provides interesting information about the stability of plasma sheath and charge particle dynamics in it that are important to understand the underlying basic sheath physics along with applications in plasma acceleration and propulsion.

An ultrasound needle insertion guide in a porcine phantom model.

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Whittaker, S; Lethbridge, G; Kim, C; Keon Cohen, Z; Ng, I

2013-08-01

We compared nerve blockade with and without the Infiniti(TM) needle guide in an ultrasound in-plane porcine simulation. We recruited 30 anaesthetists with varying blockade experience. Using the guide, the needle tip was more visible (for a median (IQR [range]) of 67 (56-100]) % of the time; and invisible for 2 (1-4 [0-19]) s) than when the guide was not used (respectively 23 (13-43 [0-80]) % and 25 (9-52 [1-198]) s; both p < 0.001). The corresponding block times were 8 (6-10 [3-28]) s and 32 (15-67 [5-225]) s, respectively; p < 0.001. The needle guide reduced the block time and the time that the needle was invisible, irrespective of anaesthetist experience. Anaesthesia © 2013 The Association of Anaesthetists of Great Britain and Ireland.

Should fine needle aspiration cytology in breast assessment be abandoned?

International Nuclear Information System (INIS)

Litherland, Janet C.

2002-01-01

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)

Measurement of bio-impedance with a smart needle to confirm percutaneous kidney access.

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Hernandez, D J; Sinkov, V A; Roberts, W W; Allaf, M E; Patriciu, A; Jarrett, T W; Kavoussi, L R; Stoianovici, D

2001-10-01

The traditional method of percutaneous renal access requires freehand needle placement guided by C-arm fluoroscopy, ultrasonography, or computerized tomography. This approach provides limited objective means for verifying successful access. We developed an impedance based percutaneous Smart Needle system and successfully used it to confirm collecting system access in ex vivo porcine kidneys. The Smart Needle consists of a modified 18 gauge percutaneous access needle with the inner stylet electrically insulated from the outer sheath. Impedance is measured between the exposed stylet tip and sheath using Model 4275 LCR meter (Hewlett-Packard, Sunnyvale, California). An ex vivo porcine kidney was distended by continuous gravity infusion of 100 cm. water saline from a catheter passed through the parenchyma into the collecting system. The Smart Needle was gradually inserted into the kidney to measure depth precisely using a robotic needle placement system, while impedance was measured continuously. The Smart Needle was inserted 4 times in each of 4 kidneys. When the needle penetrated the distended collecting system in 11 of 16 attempts, a characteristic sharp drop in resistivity was noted from 1.9 to 1.1 ohm m. Entry into the collecting system was confirmed by removing the stylet and observing fluid flow from the sheath. This characteristic impedance change was observed only at successful entry into the collecting system. A characteristic sharp drop in impedance signifies successful entry into the collecting system. The Smart Needle system may prove useful for percutaneous kidney access.

Enhanced Visualization of Fine Needles Under Sonographic Guidance Using a MEMS Actuator

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Zhiyuan Shen

2015-01-01

Full Text Available Localization of a needle tip is important for biopsy examinations in clinics. However, the needle tip is sometimes difficult to discern under the guidance of sonography due to its poor visibility. A mini actuator that radiates a low-intensity ultrasound wave was manufactured using micro-electro-mechanical system (MEMS technology. Interference between the radiated and diagnostic ultrasound pulses was observed as bright lines in the B-mode ultrasound image, from which the mini actuator could be recognized with ease. Because the distance between the mini actuator and the needle tip is fixed, the needle tip can be determined despite its inconsistent appearance in the sonography. Both gel phantom and ex vivo tissue evaluation showed that the needle tip can be determined reliably utilizing the acoustic interference pattern.

Effect of ponderosa pine needle litter on grass seedling survival.

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Burt R. McConnell; Justin G. Smith

1971-01-01

Hard fescue survival rates were followed for 6 years on four different pine needle treatment plots. Needle litter had a significant effect on initial survival of fescue seedlings, but subsequent losses undoubtedly resulted from the interaction of many factors.

Vanadium oxide (VO) based low cost counter electrode in dye sensitized solar cell (DSSC) applications

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Vijayakumar, P.; Pandian, Muthu Senthil; Ramasamy, P., E-mail: ramasamyp@ssn.edu.in [SSN Research Centre, SSN College of Engineering, Kalavakkam-603 110, Chennai, Tamilnadu (India)

2015-06-24

Vanadium oxide nanostars were synthesized by chemical method. The prepared Vanadium oxide nanostars are introduced into dye sensitized solar cell (DSSC) as counter electrode (CE) catalyst to replace the expensive platinum (Pt). The products were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) method. The photovoltaic performance of the VO as counter electrode based DSSC was evaluated under simulated standard global AM 1.5G sunlight (100 mW/cm{sup 2}). The solar to electrical energy conversion efficiency (η) of the DSSC was found to be 0.38%.This work expands the Counter electrode catalyst, which can help to reduce the cost of DSSC and thereby encourage their fundamental research and commercial application.

Driven Around the Bend: Novel Use of a Curved Steerable Needle

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Murphy, Darra T., E-mail: darra.murphy@vch.ca; Korzan, Jeffrey R.; Ouellette, Hugue A.; Liu, David M. [Vancouver General Hospital, Department of Radiology (Canada); Clarkson, Paul W. [Vancouver General Hospital, Department of Orthopedic Surgery (Canada); Munk, Peter L. [Vancouver General Hospital, Department of Radiology (Canada)

2013-04-15

This technical note describes the novel use of a curved, steerable needle to access symptomatic osseous lesions in the pelvis and sacrum for palliative percutaneous treatment that would otherwise be difficult to treat using conventional straight needles. Seven patients with lytic bone lesions were treated. One patient had multiple myeloma; the remaining had metastatic disease: breast carcinoma (n = 2), colorectal carcinoma (n = 1), renal cell carcinoma (n = 1), squamous cell carcinoma (n = 1), and leiomyosarcoma (n = 1). Five of the seven patients had lesions in the posterior acetabulum, and the two other patients had lesions in the sacrum. Four of the seven patients received radiofrequency ablation followed by cementoplasty; three patients received cementation alone. We used a novel needle designed for vertebroplasty, which has an articulating tip allowing it to be guided into lytic bone lesions located in difficult-to-access regions of the pelvis and sacrum. All patients were successfully treated with cementoplasty either with or without thermal ablation. No serious adverse events were reported. The needle was difficult to withdraw in two patients. Steerable curved needles can be successfully used to treat lytic osseous metastases with cementoplasty when lesions are located in sites that may be difficult to reach using conventional straight needles.

Darning Needle Impacted in the Male Urethra | Singla | African ...

African Journals Online (AJOL)

Foreign bodies of varied nature have been introduced into the urethra to achieve sexual stimulation. We report the case of a long (9.5 cm) darning needle impacted in the urethra of a male patient following urethral masturbation. After a failed trial at endoscopic extraction the needle had to be removed via open surgery.

Ultrasound-guided core needle biopsy for breast cancer

International Nuclear Information System (INIS)

Naqvi, S.Q.H.; Solangi, R.A.; Memon, M.; Solangi, R.A.

2008-01-01

To evaluate the efficacy of ultrasound-guided core needle biopsy (US-CNB) as a preoperative diagnostic modality for breast cancer. Females with solid and/or intermediate breast lesions visualized on ultrasonography. Apart from clinical work-up, all the above mentioned patients underwent ultrasound-guided core needle biopsy and excisional biopsy of their breast lesions. The histopathological diagnosis on ultrasound-guided core needle biopsy was then compared with the findings of the excisional biopsy. Out of the total 93 cases, 47(50.5%) had benign lesions on ultrasound; US-CNB showed 24 as fibroadenomata, four with chronic non-specific mastitis, five chronic suppurative mastitis, one tuberculosis, four fat necrosis, two lactational adenoma and seven cases with benign ductal hyperplasia without atypia. Nine (9.7%) cases showed suspicious abnormality on ultrasound; US-CNB revealed five cases with atypical ductal hyperplasia, one ductal carcinoma in situ and three invasive ductal carcinoma. Thirty seven (39.8%) cases were highly suggestive of malignancy on ultrasound; US-CNB showed 34 as invasive ductal carcinoma, two invasive lobular and one medullary carcinoma. Excisional biopsy confirmed the diagnosis of ultrasound-guided core needle biopsy in all cases except four; one case of chronic suppurative mastitis was diagnosed as that of tuberculosis and three cases of atypial ductal hyperplasia as invasive ductal carcinoma. Hence there was no false positive case, but four (4.3%) false negative cases. The sensitivity of the US-CNB was thus 100% and specificity 91.1%. Ultrasound guided core needle biopsy is a satisfactory procedure for the histopathological diagnosis of breast lesions. Any unsatisfactory, suspicious or atypical change on US-CNB should be followed by an open biopsy. (author)

Needle displacement during HDR brachytherapy in the treatment of prostate cancer

International Nuclear Information System (INIS)

Damore, Steven J.; Syed, A.M. Nisar; Puthawala, Ajmel A.; Sharma, Anil

2000-01-01

Purpose: We used clinical patient data to examine implant displacement between high dose rate (HDR) brachytherapy fractions for prostate cancer to determine its impact on treatment delivery. Materials and Methods: We analyzed the verification films taken prior to each fraction for 96 consecutive patients treated with HDR brachytherapy boosts as part of their radiation therapy for definitive treatment of organ-confined prostate cancer at our institution. Patients were treated with 18-24 Gy in 4 fractions of HDR delivered in 40 hours followed by 36-39.6 Gy external beam radiation to the prostate. We determined the mean and maximum displacement distances of marker seeds placed in the prostate and of the implanted needles between HDR fractions. Results: Mean and maximum displacement distances between fractions were documented up to 7.6 mm and 28.5 mm, respectively, for the implant needles and 3.6 mm and 11.4 mm, respectively, for the gold marker seeds. All displacement of implant needles occurred in the caudal direction. At least 1 cm caudal displacement of needles occurred prior to 15.5% all fractions. Manual adjustment of needles was required prior to 15% of fractions, and adjustment of the CLP only was required in 24%. Most of the displacement for both the marker seeds and needles occurred between the first and second fractions. Conclusions: There is significant caudal displacement of interstitial implant needles between HDR fractions in our prostate cancer patients. Obtaining verification films and making adjustments in the treatment volume prior to each fraction is necessary to avoid significant inaccuracies in treatment delivery

Usefulness of sono-guided needle puncture for MR arthrography of the shoulder

International Nuclear Information System (INIS)

Choi, Jae Woong; Hong, Suk Ju; Suh, San Il; Yong, Hwan Suk; Kim, Jung Hyuk; Park, Cheol Min; Suh, Won Hyuck; Kim, Myung Gyu

2000-01-01

To evaluate the usefulness of sono-guided needle puncture for MR arthrography of the shoulder to locate the path of access and to control the correct placement of the needle into the shoulder. Fifteen patients with suspicion of shoulder pathology were included in this study. Patients were laid in supine positions with the arm extended and slightly abducted, the palm of the hand facing upward. A sonographic unit with a high resolution transducer with 7.5 MHz linear array was used. Axial images in the anterior aspect of the shoulder were obtained to localize the coracoid process and the anteromedical portion of the humerus. Using an aseptic technique, a 21-guage needle was advanced into the shoulder joint under ultrasonographic guidance. When the needle made contract with the articular cartilage of the humeral head, the needle was tiled to position is point in the articular cavity. Solution of 0.1 ml gadopentetate dimeglumine in 25 ml of normal saline was prepared and 12-16 ml was injected into the joint cavity. The intra-articular position of the needle and the compete distension of the shoulder joint were again confirmed by sonography. The needle was accurately placed in 14 out of 15 patients without damage to neighboring structures. It took 10 to 15 minutes to complete the procedure in 14 patients. No side effects attributable to gadopentetate dimeglumine were found. Sono-guided needle puncture for the shoulder MR arthrography can be a substitutable method for fluoroscopic guidance, with easy access, advantages of lacking radiation hazard and eliminating the need for iodized contrast agents.

Photosynthesis in Norway spruce seedlings infected by the needle rust Chrysomyxa rhododendri.

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Bauer, Helmut; Plattner, Karin; Volgger, Waltraud

2000-02-01

Chrysomyxa rhododendri (DC.) De Bary is a needle rust with a host shift between Rhododendron sp. and Norway spruce (Picea abies (L.) Karst.), penetrating only the new developing flushes of the conifer. Because little is known about its effects on trees, we investigated several parameters related to photosynthesis in artificially infected 3-year-old Norway spruce seedlings. The potential efficiency of photosystem II (PSII; derived from chlorophyll fluorescence measurements) was reduced in infected current-year needles as soon as disease symptoms were visible, about three weeks after inoculation. Two weeks later, photosynthetic O(2) evolution (P(max)) of infected needles was less than 20% of control needles, whereas respiratory O(2) uptake (R(D)) was about three times higher than that of control needles. Nonstructural carbohydrate concentrations were about 60% of control values in all parts of the shoots of infected trees. Photosynthetic inhibition was associated with marked decreases in chlorophyll concentration and chlorophyll a/b ratio but only a small reduction in carotenoid concentration. In infected trees, P(max) of noninfected 1-year-old and 2-year-old needles was 50 and 80% higher than in the corresponding age class of needles of control trees. Estimation of potential daily net dry mass production, based on P(max), R(D), specific leaf area, carbon content and needle biomass, indicated that seedlings infected once were able to produce 60%, and those infected twice only 25%, of the dry mass of controls. We conclude that afforestation and regeneration of Norway spruce is seriously impaired in regions where seedlings are frequently attacked by Chrysomyxa.

C-arm cone beam computed tomography needle path overlay for fluoroscopic guided vertebroplasty.

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Tam, Alda L; Mohamed, Ashraf; Pfister, Marcus; Chinndurai, Ponraj; Rohm, Esther; Hall, Andrew F; Wallace, Michael J

2010-05-01

Retrospective review. To report our early clinical experience using C-arm cone beam computed tomography (C-arm CBCT) with fluoroscopic overlay for needle guidance during vertebroplasty. C-arm CBCT is advanced three-dimensional (3-D) imaging technology that is currently available on state-of-the-art flat panel based angiography systems. The imaging information provided by C-arm CBCT allows for the acquisition and reconstruction of "CT-like" images in flat panel based angiography/interventional suites. As part of the evolution of this technology, enhancements allowing the overlay of cross-sectional imaging information can now be integrated with real time fluoroscopy. We report our early clinical experience with C-arm CBCT with fluoroscopic overlay for needle guidance during vertebroplasty. This is a retrospective review of 10 consecutive oncology patients who underwent vertebroplasty of 13 vertebral levels using C-arm CBCT with fluoroscopic overlay for needle guidance from November 2007 to December 2008. Procedural data including vertebral level, approach (transpedicular vs. extrapedicular), access (bilateral vs. unilateral) and complications were recorded. Technical success with the overlay technology was assessed based on accuracy which consisted of 4 measured parameters: distance from target to needle tip, distance from planned path to needle tip, distance from midline to needle tip, and distance from the anterior 1/3 of the vertebral body to needle tip. Success within each parameter required that the distance between the needle tip and parameter being evaluated be no more than 5 mm on multiplanar CBCT or fluoroscopy. Imaging data for 12 vertebral levels was available for review. All vertebral levels were treated using unilateral access and 9 levels were treated with an extrapedicular approach. Technical success rates were 92% for both distance from planned path and distance from midline to final needle tip, 100% when distance from needle tip to the anterior 1

Tattoo machines, needles and utilities.

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Rosenkilde, Frank

2015-01-01

Starting out as a professional tattooist back in 1977 in Copenhagen, Denmark, Frank Rosenkilde has personally experienced the remarkable development of tattoo machines, needles and utilities: all the way from home-made equipment to industrial products of substantially improved quality. Machines can be constructed like the traditional dual-coil and single-coil machines or can be e-coil, rotary and hybrid machines, with the more convenient and precise rotary machines being the recent trend. This development has resulted in disposable needles and utilities. Newer machines are more easily kept clean and protected with foil to prevent crosscontaminations and infections. The machines and the tattooists' knowledge and awareness about prevention of infection have developed hand-in-hand. For decades, Frank Rosenkilde has been collecting tattoo machines. Part of his collection is presented here, supplemented by his personal notes. © 2015 S. Karger AG, Basel.

Learning Ultrasound-Guided Needle Insertion Skills through an Edutainment Game

Science.gov (United States)

Chan, Wing-Yin; Ni, Dong; Pang, Wai-Man; Qin, Jing; Chui, Yim-Pan; Yu, Simon Chun-Ho; Heng, Pheng-Ann

Ultrasound-guided needle insertion is essential in many of minimally invasive surgeries or procedures, such as biopsy, drug delivery, spinal anaesthesia, etc. Accurate and safe needle insertion is a difficult task due to the high requirement of hand-eye coordination skills. Many proposed virtual reality (VR) based training systems put their emphasis on realistic simulation instead of pedagogical efficiency. The lack of schematic training scenario leads to boredom of repetitive operations. To solve this, we present our novel training system with the integration of game elements in order to retain the trainees' enthusiasm. Task-oriented scenarios, time attack scenarios and performance evaluation are introduced. Besides, some state-of-art technologies are also presented, including ultrasound simulation, needle haptic rendering as well as a mass-spring-based needle-tissue interaction simulation. These works are shown to be effective to keep the trainees up with learning.

Needle stick injury in a radiology department: a decade analysis

International Nuclear Information System (INIS)

Sayani, R.; Rajani, A.

2012-01-01

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)

Histopathologic quality of prostate core biopsy specimens: comparison of an MR-compatible biopsy needle and a ferromagnetic biopsy needle used for ultrasound-guided prostate biopsy

International Nuclear Information System (INIS)

Franiel, T.; Hamm, B.; Beyersdorff, D.; Fritzsche, F.; Staack, A.; Rost, J.

2006-01-01

Purpose: The histopathologic quality of core biopsy specimens obtained via MRI-guided prostate biopsy using a 16G MR-compatible needle was compared to that of biopsies obtained via ultrasound-guided biopsy using a conventional 18G stainless steel biopsy needle. Material and Methods: A retrospective analysis was performed for a total of 247 transrectal prostate biopsy specimens obtained from 32 patients. A total of 117 tissue cores were obtained from 15 patients (PSA of 10.8 ng/ml, age 64 years) who underwent an MRI-guided prostate biopsy using a 16G (1.7 mm) MR-compatible biopsy needle made of titanium alloy. The remaining 130 tissue cores were obtained from 17 patients (PSA of 6.7 ng/ml, age 68 years) who underwent a transrectal ultrasound-guided prostate biopsy using an 18G (1.3 mm) ferromagnetic stainless steel biopsy needle. The length and width of the histologic sections prepared from the tissue cores were measured to calculate the area. The histopathologic quality of the specimens was assessed microscopically using tissue fragmentation, the presence of crush artifacts, and the overall assessability as criteria. Each of these features was assigned a score from 0 to 3. All 3 features contributed equally to the overall score which ranged from 0 (no tissue) to 9 (optimal quality). Results: The overall quality scores assigned to the biopsies obtained with a 16G MR-compatible needle and an 18G ferromagnetic needle can be considered to be equivalent to a mean difference between patient related median scores of the specimens of -0.05 (95% confidence interval [-0.46; 0.36]) and a given equivalence limit of 1. The MRI biopsies showed more tissue fragmentation (p=0.001) but fewer crush artifacts (p=0.022) while the assessability did not differ significantly between the two needle types (p=0.064). There was also no significant difference in the calculated areas of the tissue cores (p=0.236). According to the different calibers of the biopsy needles, the lengths (p=0

Anomalous needle numbers on dwarf shoots of Pinus mugo and P. uncinata (Pinaceae

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Krystyna Boratyńska

2011-01-01

Full Text Available The frequency of occurrence of abnormal, three- (or more needle dwarf shoots of most southern and central European two-needle pine (Pinus species were studied. No specimens with more than two-needle dwarf shoots were found in a population of P. nigra Arnold subsp. salzmannii (Dunal Franco from the Iberian Peninsula and in two populations of P. uliginosa Neumann from the Sudeten Mountains in Central Europe. Single specimens were found within one population of P. pinaster Aiton from the Iberian Peninsula and among six populations of P. sylvestris L. from the Iberian Peninsula and Central Europe. Abnormal dwarf shoots mostly with three, but also four, five or six needles were found among 24 of 25 surveyed populations of P. mugo Turra and P. uncinata Ramond. The average frequency of specimens with at least one three-needle dwarf shoot was 24% for P. mugo and 20% for P. uncinata. The frequencies of occurrence varied significantly among studied populations and were highest in samples collected from the upper elevational range limits of the species in the mountains and near the northern limits of their ranges. The frequency of abnormal dwarf shoots in the same populations was significantly high in 2-3 consecutive years. Needles from three-needle dwarf shoots were not significantly shorter than those of two-needle shoots.

Aerosols on the surface of needles in the vicinity of Winterthur

International Nuclear Information System (INIS)

Wyttenbach, A.; Tobler, L.; Bajo, S.

1991-01-01

The composition and the mass of aerosols residing on the surface of one-year-old needles of Norway spruce are described. The composition of aerosols on spruce needles is compared with that of aerosols collected by air filters and the composition of the local soil. A comparison of the years 1982 and 1985 shows virtually identical conditions. Finally, possible connections between aerosol mass and inherent needle content are discussed. (author) 5 figs., 2 tabs., 13 refs

EFFICACY OF IMMUNOHISTOCHEMISTRY IN PROSTATE NEEDLE BIOPSIES

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Tameem Afroz

2016-10-01

Full Text Available BACKGROUND Prostate needle biopsies can pose a major diagnostic challenge when it comes to differentiating adenocarcinoma and its variants from its benign mimics. In needle biopsies, when the suspicious focus is small, morphological features may not suffice to differentiate it from its morphologic mimics like atrophy, basal cell hyperplasia, reactive inflammatory changes, seminal vesicles and adenosis. Immunohistochemical marker for basal cells, p63 and prostate cancer specific marker, Alpha-Methylacyl-CoA Racemase (AMACR help in overcoming such diagnostic dilemmas. MATERIALS AND METHODS We analysed 157 prostate core needle biopsies over a period of 2 years. Routine Hematoxylin and Eosin (H and E sections and immunohistochemical markers for basal cells (p63 and prostate cancer specific marker (AMACR were used. Prospective study was done on prostate needle core biopsies. Biopsy was done under ultrasound guidance with an 18-gauge needle. Biopsy was done in patients with raised serum PSA levels for exclusion of prostate carcinoma. RESULTS Over a period of two years, 157 prostate core needle biopsies were studied. 83 were benign lesions comprising 69 benign prostatic hyperplasias, five basal cell hyperplasias, four granulomatous lesions and three showed atrophic changes. Two biopsies morphologically resembled seminal vesicles. Prostate cancer specific marker, AMACR was negative in all, but two lesions. In these two lesions, it showed weak nonspecific staining. Basal cell marker p63 showed a continuous staining pattern highlighting the basal cells in all the 69 cases of benign prostatic hyperplasia, 5 cases of basal hyperplasia showed positivity in all the hyperplastic basal cells. In the two cases of seminal vesicles, it showed intense basal cell positivity. It showed a discontinuous pattern in two of the four granulomatous lesions and showed a weak, but a continuous staining pattern in the atrophic lesions. 74 were adenocarcinomas; the predominant

CT-guided core biopsy of malignant lung lesions: how many needle passes are needed?

International Nuclear Information System (INIS)

Lim, Chaehun; Han, Dae Hee; Lee, Kyo Young; Kim, Young Kyoon; Ko, Jeong Min

2013-01-01

The study aims to determine the number of needle pass in the CT-guided core needle biopsy (CNB) in making a diagnosis of pulmonary malignancy. A total of 434 CNB records were retrospectively reviewed. The specimen obtained from each needle pass was put in a formalin container and then labelled for separate histopathological reporting. The patients were divided into five groups according to the total number of needle passes (n=1, n=2, n=3, n=4 and n≥5). In each of the groups 2–4, it was analysed how many needle passes are required before a plateau in diagnostic yield is achieved. CNB produced 283 true-positive and 23 false-negative diagnosis of malignancy. Cumulative sensitivity significantly (P<0.05) increased between the first and second as well as the second and the third (if done) needle passes, but not between the third and fourth ones. Three coaxial needle passes might be optimal in the diagnosis of lung malignancy.

Synthesis and Characterization of Pine Needles Reinforced RF Matrix Based Biocomposites

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A. S. Singha

2008-01-01

Full Text Available Synthesis and characterization of pine needles reinforced thermosetting resin (Resorcinol-Formaldehyde which is most suitable as composite matrix has been reported. The polycondensation reaction between resorcinol and formaldehyde (RF in different molar ratios has been applied to the synthesis of RF polymer matrix. A thermosetting resin based composite, containing approximately 10, 20, 30 and 40% of natural fiber by weight, has been obtained by adding pine needles to the Resorcinol-Formaldehyde (RF resin. The mechanical properties of randomly oriented intimately mixed particle reinforced (Pine needles composites were determined. Effect of fiber loading in terms of weight % on mechanical properties such as tensile, compressive, and flexural and wear properties have also been evaluated. The reinforcing of the resin with Pine needles was accomplished in particle size of 200 micron by employing optimized resin. Present work reveals that mechanical properties of the RF resin increases to extensive extent when reinforced with Pine needles. Thermal (TGA/DTA and morphological studies (SEM of the resin, fiber and polymer composites thus synthesized have also been carried out.

[Acupuncture therapy for regaining consciousness in terms of acupoint location, needle insertion and needle manipulation].

Science.gov (United States)

Meng, Xianggang; Gu, Wenlong; Ma, Fen; Du, Yuzheng; Zhao, Qi

2015-03-01

Acupuncture therapy for regaining consciousness activates soreness, numbness, distention, heaviness, radiating and moving, electric shock and ant climbing sensations at the specific acupoints in the stroke patients. Radiating and moving sensations are the summary of needling sensations such as soreness, numbness and twitching presenting during lifting and thrusting manipulation. These sensations are the essential factors of the therapeutic effect of regaining consciousness. Radiating sensation refers to the conduction along meridians and radiation of soreness and numbness. Moving sensation refers to the local muscular twitching at acupoints and the involuntary movement of limbs, joints and the distal. Acupuncture at the specific acupoints achieves radiating and moving sensations for promoting the circulation in meridians, regulating qi and mind and balancing yin and yang in stroke patients. This therapy was introduced in the paper in view of acupoint location, needle insertion and manipulation.

Clarification of the characteristics of needle-tip movement during vacuum venipuncture to improve safety.

Science.gov (United States)

Fujii, Chieko

2013-01-01

Complications resulting from venipuncture include vein and nerve damage, hematoma, and neuropathic pain. Although the basic procedures are understood, few analyses of actual data exist. It is important to improve the safety standards of this technique during venipuncture. This study aimed to obtain data on actual needle movement during vacuum venipuncture in order to develop appropriate educational procedures. Six experienced nurses were recruited to collect blood samples from 64 subjects. These procedures were recorded using a digital camera. Software was then used to track and analyze motion without the use of a marker in order to maintain the sterility of the needle. Movement along the X- and Y-axes during blood sampling was examined. Approximately 2.5 cm of the needle was inserted into the body, of which 6 mm resulted from advancing or moving the needle following puncture. The mean calculated puncture angle was 15.2°. Given the hazards posed by attaching and removing the blood collection tube, as well as by manipulating the needle to fix its position, the needle became unstable whether it was fixed or not fixed. This study examined venipuncture procedures and showed that the method was influenced by increased needle movement. Focusing on skills for puncturing the skin, inserting the needle into the vein, and changing hands while being conscious of needle-tip stability may be essential for improving the safety of venipuncture.

Facile fabrication of super-hydrophobic nano-needle arrays via breath figures method.

Science.gov (United States)

Kim, Jiseok; Lew, Brian; Kim, Woo Soo

2011-12-06

Super-hydrophobic surfaces which have been fabricated by various methods such as photolithography, chemical treatment, self-assembly, and imprinting have gained enormous attention in recent years. Especially 2D arrays of nano-needles have been shown to have super-hydrophobicity due to their sharp surface roughness. These arrays can be easily generated by removing the top portion of the honeycomb films prepared by the breath figures method. The hydrophilic block of an amphiphilic polymer helps in the fabrication of the nano-needle arrays through the production of well-ordered honeycomb films and good adhesion of the film to a substrate. Anisotropic patterns with water wettability difference can be useful for patterning cells and other materials using their selective growth on the hydrophilic part of the pattern. However, there has not been a simple way to generate patterns with highly different wettability. Mechanical stamping of the nano-needle array with a polyurethane stamp might be the simplest way to fabricate patterns with wettability difference. In this study, super-hydrophobic nano-needle arrays were simply fabricated by removing the top portion of the honeycomb films. The maximum water contact angle obtained with the nano-needle array was 150°. By controlling the pore size and the density of the honeycomb films, the height, width, and density of nano-needle arrays were determined. Anisotropic patterns with different wettability were fabricated by simply pressing the nano-needle array at ambient temperature with polyurethane stamps which were flexible but tough. Mechanical stamping of nano-needle arrays with micron patterns produced hierarchical super-hydrophobic structures.PACS: 05.70.Np, 68.55.am, 68.55.jm.

Transcription through the eye of a needle: daily and annual cyclic gene expression variation in Douglas-fir needles.

Science.gov (United States)

Cronn, Richard; Dolan, Peter C; Jogdeo, Sanjuro; Wegrzyn, Jill L; Neale, David B; St Clair, J Bradley; Denver, Dee R

2017-07-24

Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal cycles and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii) needles at diurnal and circannual scales. Using mRNA sequencing, we sampled 6.1 × 10 9 reads from 19 trees and constructed a de novo pan-transcriptome reference that includes 173,882 tree-derived transcripts. Using this reference, we mapped RNA-Seq reads from 179 samples that capture daily and annual variation. We identified 12,042 diurnally-cyclic transcripts, 9299 of which showed homology to annotated genes from other plant genomes, including angiosperm core clock genes. Annual analysis revealed 21,225 circannual transcripts, 17,335 of which showed homology to annotated genes from other plant genomes. The timing of maximum gene expression is associated with light intensity at diurnal scales and photoperiod at annual scales, with approximately half of transcripts reaching maximum expression +/- 2 h from sunrise and sunset, and +/- 20 days from winter and summer solstices. Comparisons with published studies from other conifers shows congruent behavior in clock genes with Japanese cedar (Cryptomeria), and a significant preservation of gene expression patterns for 2278 putative orthologs from Douglas-fir during the summer growing season, and 760 putative orthologs from spruce (Picea) during the transition from fall to winter. Our study highlight the extensive diurnal and circannual transcriptome variability demonstrated in conifer needles. At these temporal scales, 29% of expressed transcripts show a significant diurnal cycle, and 58.7% show a significant circannual cycle. Remarkably

Arthropods and passerine birds in coniferous forest. The impact of acidification and needle-loss

Energy Technology Data Exchange (ETDEWEB)

Gunnarsson, B. [Goeteborg Univ., Dept. of Zoology, Sect. of Animal Ecology, Goeteborg (Sweden)

1995-12-31

The micro-habitat structure on coniferous trees changes as a result of needle-loss. This structural change in the vegetation may affect arthropods living in spruce Picea abies by indirect mechanisms, e.g. altered relations between prey and predators. The impact of acidification and needle-loss on some tree-living arthropods and passerine birds is reviewed. New information about the taxonomic composition of spiders in relation to needle density in a field experiments is reported. The main combined findings from the review and field experiments are: 1) Acid precipitation may be toxic because of high H{sup +} concentrations. However, simulated acid rain (pH 4.0) did not reduce the growth rate of a spruce-living spider. There is a present no evidence of toxic effect on arthropods at this level of pH. 2) Experiments in the field and laboratory and data from natural populations suggested that spruce-living arthropods are affected by the needle density of branches. These data showed a positive correlation between needle density and spider abundance. However, a large-scale field experiment could not confirm this relationship. 3) The interaction between bird predation and needle density was examined in a large-scale field experiment. There were strong negative effects of bird predation on arthropod abundance. Moreover, the taxonomic composition among spiders changed as a result of bird predation: raptorial spiders increased their relative abundance whereas sheetweb spiders decreased their relative abundance when bird predation was excluded. There were also some cases of bird predation/needle density interactions. In the absence of bird predation, the needle density affected the spider size distribution: large spiders were more common on needle-sparse branches than on needle-dens ones. The species composition was affected by similar interactions, e.g. bird predation effects on crab spiders (Thomisidae) were found on needle-sparse branches only. (Abstract Truncated)

Influence of needle position on lumbar segmental nerve root block selectivity.

Science.gov (United States)

Wolff, André P; Groen, Gerbrand J; Wilder-Smith, Oliver H

2006-01-01

In patients with chronic low back pain radiating to the leg, segmental nerve root blocks (SNRBs) are performed to predict surgical outcome and identify the putative symptomatic spinal nerve. Epidural spread may lead to false interpretation, affecting clinical decision making. Systematic fluoroscopic analysis of epidural local anesthetic spread and its relationship to needle tip location has not been published to date. Study aims include assessment of epidural local anesthetic spread and its relationship to needle position during fluoroscopy-assisted blocks. Patients scheduled for L4, L5, and S1 blocks were included in this prospective observational study. Under fluoroscopy and electrostimulation, they received 0.5 mL of a mixture containing lidocaine 5 mg and iohexol 75 mg. X-rays with needle tip and contrast were scored for no epidural spread (grade 0), local spread epidurally (grade 1), or to adjacent nerve roots (grade 2). Sixty-five patients were analyzed for epidural spread, 62 for needle position. Grade 1 epidural spread occurred in 47% of L4 and 28% of L5 blocks and grade 2 spread in 3 blocks (5%; L5 n = 1, S1 n = 2). For lumbar blocks, the needle was most frequently found in the lateral upper half of the intervertebral foramen. Epidural spread occurred more frequently with medial needle positions (P = .06). The findings suggest (P = .06) that the risk of grade 1 and 2 lumbar epidural spread, which results in decreased SNRB selectivity, is greater with medial needle positions in the intervertebral foramen. The variability in anatomic position of the dorsal root ganglion necessitates electrostimulation to guide SNRB in addition to fluoroscopy.

Study on Ballistic Absorbing Energy Character of High Performance Polyethylene Needle Felt

Science.gov (United States)

Kailiang, Zhu; Jianqiao, Fu

2017-11-01

The ballistic performance of polyethylene needle felt is tested and the failure morphology after test is also observed. The results showed that when the non-dimensionally non-stressed fibers in polyethylene needles are subjected to high-speed projectile, secondary movement such as stretching and twisting occurs first. This secondary movement is very full, it is the main way of ballistic absorbing energy of the polyethylene needle felt which can avoid the polyethylene fiber short-term rapid heating-up and destroyed. Analysis results show that under normal temperature and humidity conditions, the V50 of 6-layer forded polyethylene needle felt sample is 250m/s. At (450 ± 50) m/s speed range of the target missile, the mean value of the penetrative specific energy absorption for 3-layer forded polyethylene needle felt anti-1.1g simulated projectiles (tapered column) reaches 24.1J·m2/kg.

The intravenous injection of illicit drugs and needle sharing: an historical perspective.

Science.gov (United States)

Zule, W A; Vogtsberger, K N; Desmond, D P

1997-01-01

This study reviewed the literature on the history of needle sharing and intravenous drug abuse. Reports suggest that needle sharing was practiced by drug abusers as early as 1902 in China and 1914 in the United States. Intravenous drug abuse was first mentioned in the literature in 1925. However other references suggest that some opioid users were injecting intravenously prior to 1920. Outbreaks of malaria in Egypt, the United States, and China between 1929 and 1937 were attributed to needle sharing and intravenous injection of opioids. These reports suggest that both needle sharing and intravenous drug use were common by 1937. Factors such as medical use of intravenous injections, enactment and zealous enforcement of antinarcotic laws, and interactions among drug users in institutional settings such as regional hospitals and prisons may have contributed to the spread of both needle sharing and the intravenous technique among drug abusers.

A basic study on the development of deodorants using pine needle oil

Energy Technology Data Exchange (ETDEWEB)

Doh, K.S.; Lee, H.J. [Department of Chemical Engineering, Soongsil University, Seoul (Korea, Republic of); Kim, D.K. [Chemical Technology Division, Korea Research Institute of Chemical Technology, Taejon (Korea, Republic of)

1997-11-01

The basic study on the development of deodorant made from pine needle oil was performed. The pine needle oil(PNO) was analysed using GC, GC/MS and FT-1R analyzer for analysis of chemical concentration, chemical components and structure. The analysis results obtained from GC and GC/MS analyzer were composed to main components of {alpha},{beta}-Pinene(C{sub 10}H{sub 16}), 3-Carene (C{sub 10}H{sub 16}), {Upsilon}-terpinene(C{sub 10}H{sub 16}) and terpinolene(C{sub 10}H{sub 16}), etc. Also, the concentration of heavy metals analysed from AAS analyzer. The COD and BOD concentration of landfill leachate with pine needle oil were surveyed. As a results, the pine needle oil extracted from pine needles can be used to remove bad smells of wastes as a deodorant. (author). 13 refs., 3 figs., 3 tabs.

Comments on the variability of inherent bioelement contents of spruce needles

International Nuclear Information System (INIS)

Wyttenbach, A.; Tobler, L.; Bajo, S.

1991-01-01

Inherent needle contents are the relevant concentrations within the needle, excluding surface contaminations by aerosols. The error arising from the analysis of unwashed needles is quantified. For many elements it is the source of a large apparent variability. Spatial variability is discussed under the aspects of variability among trees within a plot and of variability among different plots. Both terms have implications as to the number of trees that should be sampled for the characterization of a plot. Variability with time is investigated by following the needle concentrations from an age of 1 to 23 months. The results give indications on favourable sampling dates and on the physiology of the different elements. All investigations refer to 20 elements, which have been determined by neutron activation analysis. (author) 6 figs., 5 tabs., 16 refs

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

Science.gov (United States)

... disorders, and psoriasis. Examples of sharps include: Needles – hollow needles used to inject drugs (medication) under the ... and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 1-888-INFO-FDA (1-888- ...

Clinical observation of needle revision and 5-fluorouracil subconjunctive injection for the dysfunctional filtering blebs

Directory of Open Access Journals (Sweden)

Yan-Hua Gao

2016-07-01

Full Text Available AIM:To investigate the efficacy and safety of needle revision with 5-fluorouracil(5-FUon the dysfunctional filtering blebs after trabeculectomy and to assess the factors that may impact the success. METHODS:Eighty-three eyes in 76 patients underwent the needle revision and 5-FU subconjunctive injection for the dysfunctional blebs after trabeculectomy and were followed up for 12mo. The intraocular pressure(IOP, the number of drugs, corneal endothclium, bleb morphology and complications were observed and recorded. RESULTS:IOP decreased significantly from 35.3±5.8mmHg(1kPa=7.5mmHgof pre-needling to 17.0±4.3mmHg of post-needling(PPCI: 10.3-11.6. Statistically, there were no significant difference on needling effect with reference to the types of glaucoma, the use of mitomycin C(MMCduring the previous filtration surgery, the ages of patients, the intervals of needling operation from previous trabeculectomy, while there were significant difference on needling effect with reference to bleb appearance before needling, and the mean number of needling in patients that had surgery within 3mo were less than those who had surgery for more than 3mo. CONCLUSION: The needle revision combined with 5-FU is a safe, effective and simple method. Dysfunctional blebs should be treated early after trabeculectomy.

Pelton turbine Needle erosion prediction based on 3D three- phase flow simulation

International Nuclear Information System (INIS)

Chongji, Z; Yexiang, X; Wei, Z; Yangyang, Y; Lei, C; Zhengwei, W

2014-01-01

Pelton turbine, which applied to the high water head and small flow rate, is widely used in the mountainous area. During the operation period the sediment contained in the water does not only induce the abrasion of the buckets, but also leads to the erosion at the nozzle which may damage the needle structure. The nozzle and needle structure are mainly used to form high quality cylindrical jet and increase the efficiency of energy exchange in the runner to the most. Thus the needle erosion will lead to the deformation of jet, and then may cause the efficiency loss and cavitation. The favourable prediction of abrasion characteristic of needle can effectively guide the optimization design and maintenance of needle structure. This paper simulated the unsteady three-dimensional multi-phase flow in the nozzle and injected jet flow. As the jet containing water and sediment is injected into the free atmosphere air with high velocity, the VOF model was adopted to predict the water and air flow. The sediment is simplified into round solid particle and the discrete particle model (DPM) was employed to predict the needle abrasion characteristic. The sand particle tracks were analyzed to interpret the mechanism of sand erosion on the needle surface. And the numerical result of needle abrasion was obtained and compared with the abrasion field observation. The similarity of abrasion pattern between the numerical results and field observation illustrated the validity of the 3D multi-phase flow simulation method

Pelton turbine Needle erosion prediction based on 3D three- phase flow simulation

Science.gov (United States)

Chongji, Z.; Yexiang, X.; Wei, Z.; Yangyang, Y.; Lei, C.; Zhengwei, W.

2014-03-01

Pelton turbine, which applied to the high water head and small flow rate, is widely used in the mountainous area. During the operation period the sediment contained in the water does not only induce the abrasion of the buckets, but also leads to the erosion at the nozzle which may damage the needle structure. The nozzle and needle structure are mainly used to form high quality cylindrical jet and increase the efficiency of energy exchange in the runner to the most. Thus the needle erosion will lead to the deformation of jet, and then may cause the efficiency loss and cavitation. The favourable prediction of abrasion characteristic of needle can effectively guide the optimization design and maintenance of needle structure. This paper simulated the unsteady three-dimensional multi-phase flow in the nozzle and injected jet flow. As the jet containing water and sediment is injected into the free atmosphere air with high velocity, the VOF model was adopted to predict the water and air flow. The sediment is simplified into round solid particle and the discrete particle model (DPM) was employed to predict the needle abrasion characteristic. The sand particle tracks were analyzed to interpret the mechanism of sand erosion on the needle surface. And the numerical result of needle abrasion was obtained and compared with the abrasion field observation. The similarity of abrasion pattern between the numerical results and field observation illustrated the validity of the 3D multi-phase flow simulation method.

Flexible electrode belt for EIT using nanofiber web dry electrodes.

Science.gov (United States)

Oh, Tong In; Kim, Tae Eui; Yoon, Sun; Kim, Kap Jin; Woo, Eung Je; Sadleir, Rosalind J

2012-10-01

Efficient connection of multiple electrodes to the body for impedance measurement and voltage monitoring applications is of critical importance to measurement quality and practicality. Electrical impedance tomography (EIT) experiments have generally required a cumbersome procedure to attach the multiple electrodes needed in EIT. Once placed, these electrodes must then maintain good contact with the skin during measurements that may last several hours. There is usually also the need to manage the wires that run between the electrodes and the EIT system. These problems become more severe as the number of electrodes increases, and may limit the practicality and portability of this imaging method. There have been several trials describing human-electrode interfaces using configurations such as electrode belts, helmets or rings. In this paper, we describe an electrode belt we developed for long-term EIT monitoring of human lung ventilation. The belt included 16 embossed electrodes that were designed to make good contact with the skin. The electrodes were fabricated using an Ag-plated PVDF nanofiber web and metallic threads. A large contact area and padding were used behind each electrode to improve subject comfort and reduce contact impedances. The electrodes were incorporated, equally spaced, into an elasticated fabric belt. We tested the electrode belt in conjunction with the KHU Mark1 multi-frequency EIT system, and demonstrate time-difference images of phantoms and human subjects during normal breathing and running. We found that the Ag-plated PVDF nanofiber web electrodes were suitable for long-term measurement because of their flexibility and durability. Moreover, the contact impedance and stability of the Ag-plated PVDF nanofiber web electrodes were found to be comparable to similarly tested Ag/AgCl electrodes.

Nitrogen-enriched carbon sheets derived from egg white by using expanded perlite template and its high-performance supercapacitors

Science.gov (United States)

Chen, Jiucun; Liu, Yinqin; Li, Wenjun; Xu, Liqun; Yang, Huan; Li, Chang Ming

2015-08-01

Nitrogen-enriched carbon sheets were synthesized using egg white as a unique carbon source and expanded perlite as a novel template. The as-prepared material was further used as an electrode material for supercapacitor applications, demonstrating excellent supercapacitance with a maximum gravimetric specific capacitance of 302 F g-1 at 0.5 A g-1 in a 3-electrode setup for a sample carbonized at 850 °C and activated for 6 h. Moreover, the carbon sheet-based capacitor with 2-symmetric electrodes showed an excellent cycle life (2% loss at 0.1 A g-1 after 10 000 cycles). The excellent performance may be attributed to the combination of the 3D carbon structure and the highly concentrated doped nitrogen component from the natural egg source for superior pseudocapacitance.

Needle localization using a moving stylet/catheter in ultrasound-guided regional anesthesia: a feasibility study

Science.gov (United States)

Beigi, Parmida; Rohling, Robert

2014-03-01

Despite the wide range and long history of ultrasound guided needle insertions, an unresolved issue in many cases is clear needle visibility. A well-known ad hoc technique to detect the needle is to move the stylet and look for changes in the needle appearance. We present a new method to automatically locate a moving stylet/catheter within a stationary cannula using motion detection. We then use this information to detect the needle trajectory and the tip. The differences between the current frame and the previous frame are detected and localized, to minimize the influence of tissue global motions. A polynomial fit based on the detected needle axis determines the estimated stylet shaft trajectory, and the extent of the differences along the needle axis represents the tip. Over a few periodic movements of the stylet including its full insertion into the cannula to the tip, a combination of polynomial fits determines the needle trajectory and the last detected point represents the needle tip. Experiments are conducted in water bath and bovine muscle tissue for several stylet/catheter materials. Results show that a plastic stylet has the best needle shaft and tip localization accuracy in the water bath with RMSE = 0:16 mm and RMSE = 0:51 mm, respectively. In the bovine tissue, the needle tip was best localized with the plastic catheter with RMSE = 0:33 mm. The stylet tip localization was most accurate with the steel stylet, with RMSE = 2:81 mm and the shaft was best localized with the plastic catheter, with RMSE = 0:32 mm.

Molecular Basis for Electron Flow Within Metal-and Electrode-Reducing Biofilms

Energy Technology Data Exchange (ETDEWEB)

Bond, Daniel R. [Univ. of Minnesota, Minneapolis, MN (United States)

2016-11-01

Electrochemical, spectral, genetic, and biochemical techniques were developed to reveal that a diverse suite of redox proteins and structural macromolecules outside the cell work together to move electrons long distances between Geobacter cells to metals and electrodes. In this project, we greatly expanded the known participants in the electron transfer pathway of Geobacter. For example, in addition to well-studied pili, polysaccharides contribute to anchoring, different cytochromes are required under different conditions, strategies change with redox potential, and the localization of these components can change depending on where cells are located in a biofilm. By inventing new electrodes compatible with real-time spectral measurements, we were able to visualize the redox status of biofilms in action, leading to a hypothesis that long-distance electron transfer is ultimately limiting in these systems and redox potentials change within biofilms. The goals of this project were met, as we were able to 1) identify new elements crucial to the expression, assembly and function of the extracellular electron transfer phenotype 2) expand spectral and electrochemical techniques to define the mechanism and route of electron transfer through the matrix, and 3) combine this knowledge to build the next generation of genetic tools for study of this complex process.

A data-driven soft sensor for needle deflection in heterogeneous tissue using just-in-time modelling.

Science.gov (United States)

Rossa, Carlos; Lehmann, Thomas; Sloboda, Ronald; Usmani, Nawaid; Tavakoli, Mahdi

2017-08-01

Global modelling has traditionally been the approach taken to estimate needle deflection in soft tissue. In this paper, we propose a new method based on local data-driven modelling of needle deflection. External measurement of needle-tissue interactions is collected from several insertions in ex vivo tissue to form a cloud of data. Inputs to the system are the needle insertion depth, axial rotations, and the forces and torques measured at the needle base by a force sensor. When a new insertion is performed, the just-in-time learning method estimates the model outputs given the current inputs to the needle-tissue system and the historical database. The query is compared to every observation in the database and is given weights according to some similarity criteria. Only a subset of historical data that is most relevant to the query is selected and a local linear model is fit to the selected points to estimate the query output. The model outputs the 3D deflection of the needle tip and the needle insertion force. The proposed approach is validated in ex vivo multilayered biological tissue in different needle insertion scenarios. Experimental results in five different case studies indicate an accuracy in predicting needle deflection of 0.81 and 1.24 mm in the horizontal and vertical lanes, respectively, and an accuracy of 0.5 N in predicting the needle insertion force over 216 needle insertions.

Imaging of implant needles for real-time HDR-brachytherapy prostate treatment using biplane ultrasound transducers.

Science.gov (United States)

Siebert, Frank-André; Hirt, Markus; Niehoff, Peter; Kovács, György

2009-08-01

Ultrasound imaging is becoming increasingly important in prostate brachytherapy. In high-dose-rate (HDR) real-time planning procedures the definition of the implant needles is often performed by transrectal ultrasound. This article describes absolute measurements of the visibility and accuracy of manual detection of implant needle tips and compares measurement results of different biplane ultrasound systems in transversal and longitudinal (i.e., sagittal) ultrasound modes. To obtain a fixed coordinate system and stable conditions the measurements were carried out in a water tank using a dedicated marker system. Needles were manually placed in the phantom until the observer decided by the real-time ultrasound image that the zero position was reached. A comparison of three different ultrasound systems yielded an offset between 0.8 and 3.1 mm for manual detection of the needle tip in ultrasound images by one observer. The direction of the offset was discovered to be in the proximal direction, i.e., the actual needle position was located more distally compared to the ultrasound-based definition. In the second part of the study, the ultrasound anisotropy of trocar implant needles is reported. It was shown that the integrated optical density in a region of interest around the needle tip changes with needle rotation. Three peaks were observed with a phase angle of 120 degrees. Peaks appear not only in transversal but also in longitudinal ultrasound images, with a phase shift of 60 degrees. The third section of this study shows results of observer dependent influences on needle tip detection in sagittal ultrasound images considering needle rotation. These experiments were carried out using the marker system in a water tank. The needle tip was placed exactly at the position z=0 mm. It was found that different users tend to differently interpret the same ultrasound images. The needle tip was manually detected five times in the ultrasound images by three experienced observers

Endoscopic treatment for pancreatic diseases: Needle-knife-guided cannulation via the minor papilla.

Science.gov (United States)

Wang, Wei; Gong, Biao; Jiang, Wei-Song; Liu, Lei; Bielike, Kouken; Xv, Bin; Wu, Yun-Lin

2015-05-21

To determine the efficacy and safety of meticulous cannulation by needle-knife. Three needle-knife procedures were used to facilitate cannulation in cases when standard cannulation techniques failed. A total of 104 cannulations via the minor papilla attempted in 74 patients at our center between January 2008 and June 2014 were retrospectively reviewed. Standard methods were successful in 79 cannulations. Of the 25 cannulations that could not be performed by standard methods, 19 were performed by needle-knife, while 17 (89.5%) were successful. Needle-knife use improved the success rate of cannulation [76.0%, 79/104 vs 92.3%, (79 + 17)/104; P = 0.001]. When the 6 cases not appropriate for needle-knife cannulation were excluded, the success rate was improved further (80.6%, 79/98 vs 98.0%, 96/98; P = 0.000). There were no significant differences in the rates of post-endoscopic retrograde cholangiopancreatography adverse events between the group using standard methods alone and the group using needle-knife after failure of standard methods (4.7% vs 10.5%, P = 0.301). The needle-knife procedure may be an alternative method for improving the success rate of cannulation via the minor papilla, particularly when standard cannulation has failed.

Injecting drug use in prison: prevalence and implications for needle exchange policy.

Science.gov (United States)

Wright, Nat M J; Tompkins, Charlotte N E; Farragher, Tracey M

2015-01-01

The purpose of this paper is to explore prison drug injecting prevalence, identify any changes in injecting prevalence and practice during imprisonment and explore views on prison needle exchange. An empirical prospective cohort survey conducted between 2006 and 2008. The study involved a random sample of 267 remand and sentenced prisoners from a large male category B prison in England where no prison needle exchange operates. Questionnaires were administered with prisoners on reception and, where possible, at one, three and six months during their sentence. In total, 64 per cent were injecting until admission into prison. The majority intended to stop injecting in prison (93 per cent), almost a quarter due to the lack of needle exchange (23 per cent). Yet when hypothetically asked if they would continue injecting in prison if needle exchange was freely available, a third of participants (33 per cent) believed that they would. Injecting cessation happened on prison entry and appeared to be maintained during the sentence. Not providing sterile needles may increase risks associated with injecting for prisoners who continue to inject. However, providing such equipment may prolong injecting for other prisoners who currently cease injecting on account of needle exchange programmes (NEPs) not being provided in the UK prison setting. Practical implications - Not providing sterile needles may increase risks associated with injecting for prisoners who continue to inject. However, providing such equipment may prolong injecting for other prisoners who currently cease injecting on account of NEPs not being provided in the UK prison setting. This survey is the first to question specifically regarding the timing of injecting cessation amongst male prisoners and explore alongside intention to inject should needle exchange facilities be provided in prison.

Dry needling and exercise for chronic whiplash - a randomised controlled trial

Directory of Open Access Journals (Sweden)

Souvlis Tina

2009-12-01

Full Text Available Abstract Background Chronic whiplash is a common and costly problem. Sensory hypersensitivity is a feature of chronic whiplash that is associated with poor responsiveness to physical treatments such as exercise. Modalities such as dry-needling have shown some capacity to modulate sensory hypersensitivity, suggesting that when combined with advice and exercise, such an approach may be more effective in the management of chronic whiplash. The primary aim of this project is to investigate the effectiveness of dry-needling, advice and exercise for chronic whiplash. Method/Design A double-blind randomised controlled trial will be conducted. 120 participants with chronic whiplash, grade II will be randomised to receive either 1 dry-needling, advice and exercise or 2 sham dry-needling, advice and exercise. All participants will receive an educational booklet on whiplash. Participants who are randomised to Group 1 will receive 6 treatments of combined dry-needling and exercise delivered in the first 3 weeks of the 6 week program, and 4 treatments of exercise only in the last 3 weeks of the program. Participants randomised to Group 2 will receive an identical protocol, except that a sham dry-needling technique will be used instead of dry-needling. The primary outcome measures are the Neck Disability Index (NDI and participants' perceived recovery. Outcomes will be measured at 6, 12, 24 and 52 weeks after randomization by an assessor who is blind to the group allocation of the participants. In parallel, an economic analysis will be conducted. Discussion This trial will utilise high quality trial methodologies in accordance with CONSORT guidelines. The successful completion of this trial will provide evidence of the effectiveness and cost-effectiveness of a combined treatment approach for the management of chronic whiplash. Trial registration ACTRN12609000470291

MAINTENANCE PLANNING OF THE SEWING NEEDLES OF SIMPLE SEWING MACHINES

Directory of Open Access Journals (Sweden)

ŞUTEU Marius Darius

2017-05-01

Full Text Available The effectiveness of simple sewing machines can be increased through the planning of predictive maintenance activities. The monitoring of the technical condition of the sewing needles of simple sewing machines was based on the measurement of their noise level. For this purpose a Center 322 sonometer was used, while the data obtained during the monitoring process was analyzed through the E322 software. The working speed of the simple sewing machine that was used for obtaining the experimental results varied from 200 stitches/minute to 4000 stitches/minute. The noise levels of a new needle at the working speed of 200 stitches/minute and 4000 stitches/minute were measured. The noise levels for a fault needle at the same working speed of 200 stitches/minute, respectively 4000 stitches/minute were also measured. Using Fuzzy Logic Toolbox ™ module of Matlab®, a decision-making system for determining when replacement of the sewing needles of simple sewing machines should be performed was developed. A case study illustrates the employment of the decision-making system based on fuzzy logic for a simple sewing machine. By replacing the sewing needles of simple sewing machines at the time specified through the decision-making system based on fuzzy logic, the occurrence of the failure can be prevented and the quality of textile products can be improved.

Percutaneous Emergency Needle Caecostomy for Prevention of Caecal Perforation.

Science.gov (United States)

Limmer, Alexandra M; Clement, Zackariah

2017-01-01

Caecal perforation is a life-threatening complication of large bowel obstruction with a reported mortality of 34% to 72%. This case describes the novel use of percutaneous needle caecostomy as a life-saving measure to prevent imminent caecal perforation in a 68-year-old lady with large bowel obstruction secondary to an incarcerated incisional hernia. After careful review of computed tomography images and measurement of distances from the abdominal wall to the caecum, the patient's caecum was decompressed in the emergency department using a needle under local anaesthetic. The patient subsequently underwent laparoscopic hernia repair and had an uncomplicated recovery. When conducted safely and with precision in an appropriate patient, percutaneous needle caecostomy can provide immediate symptom relief, reduce risk of caecal perforation, and allow a laparoscopic surgical approach.

Percutaneous Emergency Needle Caecostomy for Prevention of Caecal Perforation

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Alexandra M. Limmer

2017-01-01

Full Text Available Caecal perforation is a life-threatening complication of large bowel obstruction with a reported mortality of 34% to 72%. This case describes the novel use of percutaneous needle caecostomy as a life-saving measure to prevent imminent caecal perforation in a 68-year-old lady with large bowel obstruction secondary to an incarcerated incisional hernia. After careful review of computed tomography images and measurement of distances from the abdominal wall to the caecum, the patient’s caecum was decompressed in the emergency department using a needle under local anaesthetic. The patient subsequently underwent laparoscopic hernia repair and had an uncomplicated recovery. When conducted safely and with precision in an appropriate patient, percutaneous needle caecostomy can provide immediate symptom relief, reduce risk of caecal perforation, and allow a laparoscopic surgical approach.

Pharmacies as providers of expanded health services for people who inject drugs: a review of laws, policies, and barriers in six countries.

Science.gov (United States)

Hammett, Theodore M; Phan, Son; Gaggin, Julia; Case, Patricia; Zaller, Nicholas; Lutnick, Alexandra; Kral, Alex H; Fedorova, Ekaterina V; Heimer, Robert; Small, Will; Pollini, Robin; Beletsky, Leo; Latkin, Carl; Des Jarlais, Don C

2014-06-17

People who inject drugs (PWID) are underserved by health providers but pharmacies may be their most accessible care settings. Studies in the U.S., Russia, Vietnam, China, Canada and Mexico employed a three-level (macro-, meso-, and micro-) model to assess feasibility of expanded pharmacy services for PWID. Studies employed qualitative and quantitative interviews, review of legal and policy documents, and information on the knowledge, attitudes, and practices of key stakeholders. Studies produced a mixed assessment of feasibility. Provision of information and referrals by pharmacies is permissible in all study sites and sale and safe disposal of needles/syringes by pharmacies is legal in almost all sites, although needle/syringe sales face challenges related to attitudes and practices of pharmacists, police, and other actors. Pharmacy provision of HIV testing, hepatitis vaccination, opioid substitution treatment, provision of naloxone for drug overdose, and abscess treatment, face more serious legal and policy barriers. Challenges to expanded services for drug users in pharmacies exist at all three levels, especially the macro-level characterized by legal barriers and persistent stigmatization of PWID. Where deficiencies in laws, policies, and community attitudes block implementation, stakeholders should advocate for needed legal and policy changes and work to address community stigma and resistance. Laws and policies are only as good as their implementation, so attention is also needed to meso- and micro- levels. Policies, attitudes, and practices of police departments and pharmacy chains as well as knowledge, attitudes, and practices of individual PWID, individual pharmacies, and police officers should support rather than undermine positive laws and expanded services. Despite the challenges, pharmacies remain potentially important venues for delivering health services to PWID.

Clinical application of percutaneous needling lung abscess drairnage under CT guidance

International Nuclear Information System (INIS)

Hu Xiaokun; Wang Mingyou; Li Chenjun; Lv Dongfang; Li Xiaodong; Yu Zhaocun

2004-01-01

Objective: To discuss the clinical application of drainage for lung abscess by needle puncture under CT guidance. Methods: 18 cases of lung abscess were drainaged by needle puncture under CT guidance, including direct aspiration by puncture needle 1-3 times (n=8) and retaining drainage tube continuously (n=10). Results: 17 cases with this procedure were succeeded possessing success rate of 94.7%(17/18). The patients were followed up for 11-35 days with symptom relieving better obviously and the focus shrinkage or disappeared (n=16), the curative rate reached 88.9%(16/18). The main complication was pneumothorax with capacities of 30%(n=1). Conclusions: The curative course of lung abscess can be shortened greatly by percutaneous needling drainage under CT guidance with mild trauma. The procedure is simple with high successful rate and less complication. (authors)

Dynamics of Pinus sylvestris L. needles activity in Predbaikal’ye forests

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I.M. Romanova

2013-11-01

Full Text Available The study was aimed to analyse changes in peroxidase activity of common pine needles throughout the year. The needles of the 1-st, 2-nd and 3-d years were collected. Total activity of guaiacol-dependent peroxidase was determined. Minimum peroxidase activity is observed in January and February. In March intense overall activation of peroxidase is observed in the needles of all ages, which might be related to spring enhancement of physiological processes and activation of metabolism. Autumn period is characterized by more or less high activities of guaiacol peroxidase from September till November, which is related to its participation in stress-adaptation to low temperatures in winter. Peroxidase activity changes depending on the season of the year. Needles of different age are characterized by their own peroxidase activity level in various time periods.

A novel technique of rotator cuff repair using spinal needle and suture loop

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Muzaffar Nasir

2010-11-01

Full Text Available Abstract Background We present a simple technique of arthroscopic rotator cuff repair using a spinal needle and suture loop. Methods With the arthroscope laterally, a spinal needle looped with PDS is inserted percutaneously into the shoulder posteriorly and penetrated through the healthy posterior cuff tear margin. Anteriorly, another spinal needle loaded with PDS is inserted percutaneously to engage the healthy tissue at the anterior tear margin. The suture in the anterior needle is then delivered into the suture loop of the posterior needle using a suture retriever. The posterior needle and loop are then pulled out carrying the anterior suture with it. The two limbs of this suture are then retrieved through a cannula for knotting. The same procedure is then repeated for additional suturing. Suture anchors placed over the greater tuberosity are used to complete the repair. Conclusion This is an easy method of rotator cuff repair using simple instruments and lesser time, hence can be employed at centers with less equipment and at reduced cost to the patient.

Pen needle design influences ease of insertion, pain, and skin trauma in subjects with type 2 diabetes.

Science.gov (United States)

Præstmark, Kezia A; Jensen, Morten L; Madsen, Nils B; Kildegaard, Jonas; Stallknecht, Bente M

2016-01-01

Pen needles used for subcutaneous injections have gradually become shorter, thinner and more thin walled, and thereby less robust to patient reuse. Thus, different needle sizes, alternative tip designs and needles resembling reuse were tested to explore how needle design influences ease of insertion, pain and skin trauma. 30 subjects with injection-treated type 2 diabetes and body mass index 25-35 kg/m 2 were included in the single-blinded study. Each subject received abdominal insertions with 18 different types of needles. All needles were tested twice per subject and in random order. Penetration force (PF) through the skin, pain perception on 100 mm visual analog scale, and change in skin blood perfusion (SBP) were quantified after the insertions. Needle diameter was positively related to PF and SBP (ptrend relation. Lack of needle lubrication and small 'needle hooks' increased PF and SBP (pskin and in polyurethane rubber were linearly related, and pain outcome was dependent of SBP increase. The shape and design of a needle and the needle tip affect ease of insertion, pain and skin trauma. Relations are seen across different data acquisition methods and across species, enabling needle performance testing outside of clinical trials. NCT02531776; results.

Target motion predictions for pre-operative planning during needle-based interventions

NARCIS (Netherlands)

op den Buijs, J.; Abayazid, Momen; de Korte, Chris L.; Misra, Sarthak

During biopsies, breast tissue is subjected to displacement upon needle indentation, puncture, and penetration. Thus, accurate needle placement requires pre-operative predictions of the target motions. In this paper, we used ultrasound elastography measurements to non-invasively predict elastic

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

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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

Decadal strain along creeping faults in the Needles District, Paradox Basin Utah determined with InSAR Time Series Analysis

Science.gov (United States)

Kravitz, K.; Furuya, M.; Mueller, K. J.

2013-12-01

The Needles District, in Canyonlands National Park in Utah exposes an array of actively creeping normal faults that accommodate gravity-driven extension above a plastically deforming substrate of evaporite deposits. Previous interferogram stacking and InSAR analysis of faults in the Needles District using 35 ERS satellite scenes from 1992 to 2002 showed line-of-sight deformation rates of ~1-2 mm/yr along active normal faults, with a wide strain gradient along the eastern margin of the deforming region. More rapid subsidence of ~2-2.5 mm/yr was also evident south of the main fault array across a broad platform bounded by the Colorado River and a single fault scarp to the south. In this study, time series analysis was performed on SAR scenes from Envisat, PALSAR, and ERS satellites ranging from 1992 to 2010 to expand upon previous results. Both persistent scatterer and small baseline methods were implemented using StaMPS. Preliminary results from Envisat data indicate equally distributed slip rates along the length of faults within the Needles District and very little subsidence in the broad region further southwest identified in previous work. A phase ramp that appears to be present within the initial interferograms creates uncertainty in the current analysis and future work is aimed at removing this artifact. Our new results suggest, however that a clear deformation signal is present along a number of large grabens in the northern part of the region at higher rates of up to 3-4 mm/yr. Little to no creep is evident along the single fault zone that bounds the southern Needles, in spite of the presence of a large and apparently active fault. This includes a segment of this fault that is instrumented by a creepmeter that yields slip rates on the order of ~1mm/yr. Further work using time series analysis and a larger sampling of SAR scenes will be used in an effort to determine why differences exist between previous and current work and to test mechanics-based modeling

WE-G-204-08: Optimized Digital Radiographic Technique for Lost Surgical Devices/Needle Identification

International Nuclear Information System (INIS)

Gorman, A; Seabrook, G; Brakken, A; Dubois, M; Marn, C; Wilson, C; Jacobson, D; Liu, Y

2015-01-01

Purpose: Small surgical devices and needles are used in many surgical procedures. Conventionally, an x-ray film is taken to identify missing devices/needles if post procedure count is incorrect. There is no data to indicate smallest surgical devices/needles that can be identified with digital radiography (DR), and its optimized acquisition technique. Methods: In this study, the DR equipment used is a Canon RadPro mobile with CXDI-70c wireless DR plate, and the same DR plate on a fixed Siemens Multix unit. Small surgical devices and needles tested include Rubber Shod, Bulldog, Fogarty Hydrogrip, and needles with sizes 3-0 C-T1 through 8-0 BV175-6. They are imaged with PMMA block phantoms with thickness of 2–8 inch, and an abdomen phantom. Various DR techniques are used. Images are reviewed on the portable x-ray acquisition display, a clinical workstation, and a diagnostic workstation. Results: all small surgical devices and needles are visible in portable DR images with 2–8 inch of PMMA. However, when they are imaged with the abdomen phantom plus 2 inch of PMMA, needles smaller than 9.3 mm length can not be visualized at the optimized technique of 81 kV and 16 mAs. There is no significant difference in visualization with various techniques, or between mobile and fixed radiography unit. However, there is noticeable difference in visualizing the smallest needle on a diagnostic reading workstation compared to the acquisition display on a portable x-ray unit. Conclusion: DR images should be reviewed on a diagnostic reading workstation. Using optimized DR techniques, the smallest needle that can be identified on all phantom studies is 9.3 mm. Sample DR images of various small surgical devices/needles available on diagnostic workstation for comparison may improve their identification. Further in vivo study is needed to confirm the optimized digital radiography technique for identification of lost small surgical devices and needles

Determining the Optimal Number of Core Needle Biopsy Passes for Molecular Diagnostics.

Science.gov (United States)

Hoang, Nam S; Ge, Benjamin H; Pan, Lorraine Y; Ozawa, Michael G; Kong, Christina S; Louie, John D; Shah, Rajesh P

2018-03-01

The number of core biopsy passes required for adequate next-generation sequencing is impacted by needle cut, needle gauge, and the type of tissue involved. This study evaluates diagnostic adequacy of core needle lung biopsies based on number of passes and provides guidelines for other tissues based on simulated biopsies in ex vivo porcine organ tissues. The rate of diagnostic adequacy for pathology and molecular testing from lung biopsy procedures was measured for eight operators pre-implementation (September 2012-October 2013) and post-implementation (December 2013-April 2014) of a standard protocol using 20-gauge side-cut needles for ten core biopsy passes at a single academic hospital. Biopsy pass volume was then estimated in ex vivo porcine muscle, liver, and kidney using side-cut devices at 16, 18, and 20 gauge and end-cut devices at 16 and 18 gauge to estimate minimum number of passes required for adequate molecular testing. Molecular diagnostic adequacy increased from 69% (pre-implementation period) to 92% (post-implementation period) (p < 0.001) for lung biopsies. In porcine models, both 16-gauge end-cut and side-cut devices require one pass to reach the validated volume threshold to ensure 99% adequacy for molecular characterization, while 18- and 20-gauge devices require 2-5 passes depending on needle cut and tissue type. Use of 20-gauge side-cut core biopsy needles requires a significant number of passes to ensure diagnostic adequacy for molecular testing across all tissue types. To ensure diagnostic adequacy for molecular testing, 16- and 18-gauge needles require markedly fewer passes.

Use of a Puncture Needle for Recanalization of an Occluded Right Subclavian Vein

International Nuclear Information System (INIS)

Gupta, Himanshu; Murphy, Timothy P.; Soares, Gregory M.

1998-01-01

We report a patient in whom we used a puncture needle to initiate percutaneous recanalization of a chronic occlusion of the junction between the right subclavian vein and the right brachiocephalic vein. Under fluoroscopic guidance, an 18-gauge needle was used to puncture the right subclavian vein. When contrast material injected through the needle confirmed intravascular location, the needle was advanced until it deflected and perforated an occlusion balloon target positioned within the right brachiocephalic vein. This technique may be useful in patients with central venous occlusions that are refractory to traversal using traditional catheter and guidewire techniques

Clarification of the characteristics of needle-tip movement during vacuum venipuncture to improve safety

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Fujii C

2013-07-01

Full Text Available Chieko FujiiFaculty of Nursing and Medical Care, Keio University, Kanagawa, JapanBackground: Complications resulting from venipuncture include vein and nerve damage, hematoma, and neuropathic pain. Although the basic procedures are understood, few analyses of actual data exist. It is important to improve the safety standards of this technique during venipuncture. This study aimed to obtain data on actual needle movement during vacuum venipuncture in order to develop appropriate educational procedures.Methods: Six experienced nurses were recruited to collect blood samples from 64 subjects. These procedures were recorded using a digital camera. Software was then used to track and analyze motion without the use of a marker in order to maintain the sterility of the needle. Movement along the X- and Y-axes during blood sampling was examined.Results: Approximately 2.5 cm of the needle was inserted into the body, of which 6 mm resulted from advancing or moving the needle following puncture. The mean calculated puncture angle was 15.2°. Given the hazards posed by attaching and removing the blood collection tube, as well as by manipulating the needle to fix its position, the needle became unstable whether it was fixed or not fixed.Conclusion: This study examined venipuncture procedures and showed that the method was influenced by increased needle movement. Focusing on skills for puncturing the skin, inserting the needle into the vein, and changing hands while being conscious of needle-tip stability may be essential for improving the safety of venipuncture.Keywords: blood collection, nerve damage, motion analysis, patient safety, puncture angle, clinical education

Non-activated high surface area expanded graphite oxide for supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Vermisoglou, E.C.; Giannakopoulou, T.; Romanos, G.E.; Boukos, N.; Giannouri, M. [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece); Lei, C.; Lekakou, C. [Division of Mechanical, Medical, and Aerospace Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); Trapalis, C., E-mail: c.trapalis@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece)

2015-12-15

Graphical abstract: - Highlights: • One-step exfoliation and reduction of graphite oxide via microwave irradiation. • Effect of pristine graphite (type, flake size) on the microwave expanded material. • Effect of pretreatment and oxidation cycles on the produced expanded material. • Expanded graphene materials with high BET surface areas (940 m{sup 2}/g–2490 m{sup 2}/g). • Non-activated graphene based materials suitable for supercapacitors. - Abstract: Microwave irradiation of graphite oxide constitutes a facile route toward production of reduced graphene oxide, since during this treatment both exfoliation and reduction of graphite oxide occurs. In this work, the effect of pristine graphite (type, size of flakes), pretreatment and oxidation cycles on the finally produced expanded material was examined. All the types of graphite that were tested afforded materials with high BET surface areas ranging from 940 m{sup 2}/g to 2490 m{sup 2}/g, without intervening an activation stage at elevated temperature. SEM and TEM images displayed exfoliated structures, where the flakes were significantly detached and curved. The quality of the reduced graphene oxide sheets was evidenced both by X-ray photoelectron spectroscopy and Raman spectroscopy. The electrode material capacitance was determined via electrochemical impedance spectroscopy and cyclic voltammetry. The materials with PEDOT binder had better performance (∼97 F/g) at low operation rates while those with PVDF binder performed better (∼20 F/g) at higher rates, opening up perspectives for their application in supercapacitors.

Detection of needle to nerve contact based on electric bioimpedance and machine learning methods.

Science.gov (United States)

Kalvoy, Havard; Tronstad, Christian; Ullensvang, Kyrre; Steinfeldt, Thorsten; Sauter, Axel R

2017-07-01

In an ongoing project for electrical impedance-based needle guidance we have previously showed in an animal model that intraneural needle positions can be detected with bioimpedance measurement. To enhance the power of this method we in this study have investigated whether an early detection of the needle only touching the nerve also is feasible. Measurement of complex impedance during needle to nerve contact was compared with needle positions in surrounding tissues in a volunteer study on 32 subjects. Classification analysis using Support-Vector Machines demonstrated that discrimination is possible, but that the sensitivity and specificity for the nerve touch algorithm not is at the same level of performance as for intra-neuralintraneural detection.

Effect of dietary mugwort ( Artemisia vulgaris L.) and pine needle ...

African Journals Online (AJOL)

The effects of dietary mugwort and pine needle powder supplementation on growth performance, serum cholesterol, and meat quality of broilers were evaluated in a 35 days feed trial. 200 one day old broilers were randomly allocated to five dietary treatments (0, 1 and 2% mugwort or 1 and 2% pine needle powder) with ...

Carbon fibre and nitinol needles for MRI-guided interventions: First in vitro and in vivo application

Energy Technology Data Exchange (ETDEWEB)

Thomas, Christoph, E-mail: Christoph.thomas@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Wojtczyk, Hanne [Section of Experimental Radiology, University of Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Rempp, Hansjoerg; Clasen, Stephan; Horger, Marius [Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Lassberg, Christoph von [Department of Sports Medicine, University of Tuebingen, Silcherstrasse 5, 72076 Tuebingen (Germany); Fritz, Jan [Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287 (United States); Claussen, Claus D. [Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Pereira, Philippe L. [Department of Radiology, Minimally Invasive Therapies and Nuclearmedicine, SLK-Kliniken Heilbronn GmbH, Am Gesundbrunnen 20-26, 74078 Heilbronn (Germany)

2011-09-15

Objective: To assess the artefact properties of a MR-compatible carbon fibre needle with a nitinol mandrin in vitro and to report first clinical experiences. Materials and methods: In vitro, the carbon fibre/nitinol needle was imaged at different angles against the main magnetic field (1.5 T open bore magnet). A gradient echo MR fluoroscopy sequence (GRE: TR 9.3 ms, TE 3.12 ms, bandwidth 200 Hz/pixel, flip-angle 12{sup o}) and a fast turbo spin echo sequence (FSE: TR 412 ms, TE 9.7 ms, bandwidth 200 Hz/pixel, flip-angle 150{sup o}) were used. Artefact width, needle intensity contrast and needle tip location errors were assessed. In vivo, lumbar periradicular corticosteroid injections and one sclerotherapy were performed with carbon fibre needles (10 procedures) and with titanium alloy needles (2 procedures). The artefact sizes and contrasts were measured. Results: In vitro, artefact diameters of the carbon fibre needle ranged from 3.3 to 4.6 mm, contrasts from 0.11 to 0.52, with larger artefact contrasts and widths with the GRE sequence. Needle tip location errors of -2.1 to -2.8 mm were observed. Decreasing angles to the main field lead to smaller artefacts. In vivo, the carbon fibre/nitinol needle produced smaller artefacts (mean width FSE/GRE: 2.8 mm/4.6 mm) with lower contrast (0.30-0.42) than the titanium alloy needle (mean width FSE/GRE: 4.1 mm/7.5 mm, contrast 0.60-0.73). Conclusions: The carbon fibre/nitinol needle is useful for performing MR-guided interventions at 1.5 T, producing more subtle artefacts than a titanium alloy needle, but with an incomplete depiction and thus inaccurate localization of the needle tip.

ExpandED Options: Learning beyond High School Walls

Science.gov (United States)

ExpandED Schools, 2014

2014-01-01

Through ExpandED Options by TASC, New York City high school students get academic credit for learning career-related skills that lead to paid summer jobs. Too many high school students--including those most likely to drop out--are bored or see classroom learning as irrelevant. ExpandED Options students live the connection between mastering new…

Force-Sensor-Based Estimation of Needle Tip Deflection in Brachytherapy

Directory of Open Access Journals (Sweden)

Thomas Lehmann

2013-01-01

in real time during needle insertion is the main contribution of this paper. The proposed approach solely relies on the measured forces and torques without a need for any other invasive/noninvasive sensing devices. A few mechanical models have been introduced previously regarding the way the forces are composed along the needle during insertion; we will compare our model to those approaches in terms of accuracy. In order to conduct experiments to verify the deflection model, a custom-built, 2-DOF robotic system for needle insertion is developed and discussed. This system is a prototype of an intelligent, hand-held surgical assistant tool that incorporates the virtual sensor proposed in this paper.

A plasma needle generates nitric oxide

International Nuclear Information System (INIS)

Stoffels, E; Gonzalvo, Y Aranda; Whitmore, T D; Seymour, D L; Rees, J A

2006-01-01

Generation of nitric oxide (NO) by a plasma needle is studied by means of mass spectrometry. The plasma needle is an atmospheric glow generated by a radio-frequency excitation in a mixture of helium and air. This source is used for the treatment of living tissues, and nitric oxide may be one of the most important active agents in plasma therapy. Efficient NO generation is of particular importance in the treatment of cardiovascular diseases. Mass spectrometric measurements have been performed under various plasma conditions; gas composition in the plasma and conversion of feed gases (nitrogen and oxygen) into other species has been studied. Up to 30% of the N 2 and O 2 input is consumed in the discharge, and NO has been identified as the main conversion product

Real-time image-based B-mode ultrasound image simulation of needles using tensor-product interpolation.

Science.gov (United States)

Zhu, Mengchen; Salcudean, Septimiu E

2011-07-01

In this paper, we propose an interpolation-based method for simulating rigid needles in B-mode ultrasound images in real time. We parameterize the needle B-mode image as a function of needle position and orientation. We collect needle images under various spatial configurations in a water-tank using a needle guidance robot. Then we use multidimensional tensor-product interpolation to simulate images of needles with arbitrary poses and positions using collected images. After further processing, the interpolated needle and seed images are superimposed on top of phantom or tissue image backgrounds. The similarity between the simulated and the real images is measured using a correlation metric. A comparison is also performed with in vivo images obtained during prostate brachytherapy. Our results, carried out for both the convex (transverse plane) and linear (sagittal/para-sagittal plane) arrays of a trans-rectal transducer indicate that our interpolation method produces good results while requiring modest computing resources. The needle simulation method we present can be extended to the simulation of ultrasound images of other wire-like objects. In particular, we have shown that the proposed approach can be used to simulate brachytherapy seeds.

Ultrasound-guided percutaneous core needle biopsy of splenic lesions

Energy Technology Data Exchange (ETDEWEB)

Park, SangIk; Shin, Yong Moon; Won, Hyung Jin; Kim, Pyo Nyun; Lee, Moon Gyu [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

2017-05-15

To evaluate the safety and efficacy of ultrasound-guided percutaneous core needle biopsy of splenic lesions. This retrospective study included 30 patients who underwent percutaneous core needle biopsy of their splenic lesions using 18- or 20-gauge needles between January 2001 and July 2016 in a single tertiary care center. The characteristics of the splenic lesions were determined by reviewing the ultrasound and computed tomography examinations. Acquisition rate and diagnostic accuracy were calculated, using pathologic results of the splenectomy specimen, clinical course and/or imaging follow-up as a reference standard. Post-procedure complications were identified from electronic medical records, laboratory findings and computed tomography images. Seventy-three specimens were obtained from the 30 patients and splenectomy was performed in 2 patients. Twenty-nine of the 30 patients had focal splenic lesions, while the remaining patient had homogeneous splenomegaly. Acquisition rate and diagnostic accuracy were 80.0% (24/30) and 76.7% (23/30), respectively. Perisplenic hemorrhage without hemodynamic instability developed in one patient. Ultrasound-guided percutaneous core needle biopsy of splenic lesions is a safe method for achieving a histopathologic diagnosis and can be considered as an alternative to splenectomy in patients with a high risk of splenectomy-related complications.

Ultrasound-guided percutaneous core needle biopsy of splenic lesions

International Nuclear Information System (INIS)

Park, SangIk; Shin, Yong Moon; Won, Hyung Jin; Kim, Pyo Nyun; Lee, Moon Gyu

2017-01-01

To evaluate the safety and efficacy of ultrasound-guided percutaneous core needle biopsy of splenic lesions. This retrospective study included 30 patients who underwent percutaneous core needle biopsy of their splenic lesions using 18- or 20-gauge needles between January 2001 and July 2016 in a single tertiary care center. The characteristics of the splenic lesions were determined by reviewing the ultrasound and computed tomography examinations. Acquisition rate and diagnostic accuracy were calculated, using pathologic results of the splenectomy specimen, clinical course and/or imaging follow-up as a reference standard. Post-procedure complications were identified from electronic medical records, laboratory findings and computed tomography images. Seventy-three specimens were obtained from the 30 patients and splenectomy was performed in 2 patients. Twenty-nine of the 30 patients had focal splenic lesions, while the remaining patient had homogeneous splenomegaly. Acquisition rate and diagnostic accuracy were 80.0% (24/30) and 76.7% (23/30), respectively. Perisplenic hemorrhage without hemodynamic instability developed in one patient. Ultrasound-guided percutaneous core needle biopsy of splenic lesions is a safe method for achieving a histopathologic diagnosis and can be considered as an alternative to splenectomy in patients with a high risk of splenectomy-related complications

Catoptric electrodes: transparent metal electrodes using shaped surfaces.

Science.gov (United States)

Kik, Pieter G

2014-09-01

An optical electrode design is presented that theoretically allows 100% optical transmission through an interdigitated metallic electrode at 50% metal areal coverage. This is achieved by redirection of light incident on embedded metal electrode lines to an angle beyond that required for total internal reflection. Full-field electromagnetic simulations using realistic material parameters demonstrate 84% frequency-averaged transmission for unpolarized illumination across the entire visible spectral range using a silver interdigitated electrode at 50% areal coverage. The redirection is achieved through specular reflection, making it nonresonant and arbitrarily broadband, provided the electrode width exceeds the optical wavelength. These findings could significantly improve the performance of photovoltaic devices and optical detectors that require high-conductivity top contacts.

[Effects of warm needling moxibustion on knee cartilage and morphology in rats with knee osteoarthritis].

Science.gov (United States)

Zhang, Yongliang; Mi, Yiqun; Gang, Jiahong; Wang, Huamin

2016-02-01

To observe the effects of warm needling moxibustion on body mass, knee cartilage andmorphology in rats with knee osteoarthritis (KOA). Forty SD rats were randomly divided into a normalgroup, a model group, a medication group and a warm needling group, 10 rats in each one. Except the normalgroup, the rats in the remaining three groups were injected with papain to establish the model of KOA. After themodeling, rats in the model group did not receive any treatment; rats in the warm needling group were treated withwarm needling moxibustion at bilateral "Xiqian"; rats in the medication group were treated with intragastric administration of meloxicam; rats in the normal group were treated with 0. 9% NaCl solution (identical dose as medication group) and immobilized as the warm needling group. The treatment was given once a day for consecutive20 days. The body mass, scale of knee cartilage and morphological changes were observed in each group after'treatment. The increasing of body mass in the medication group and warm needling group was faster than!that in the model group, but slower than that in the normal group (all Pwarm needling group was not statistically significant (P>0. 05). The scale of knee cartilage in thewarm needling group and medication group was significantly lower than that in the model group (both Pwarm needling group was lower than that in the medication group (Pwarm needlinggroup were superior to those in the medication group. The warm needling moxibustion could effectively reduce the knee pain, improve the recovery of knee cartilage, which is a safe and effective treatment.

Molecular model of a type III secretion system needle: Implications for host-cell sensing.

Science.gov (United States)

Deane, Janet E; Roversi, Pietro; Cordes, Frank S; Johnson, Steven; Kenjale, Roma; Daniell, Sarah; Booy, Frank; Picking, William D; Picking, Wendy L; Blocker, Ariel J; Lea, Susan M

2006-08-15

Type III secretion systems are essential virulence determinants for many Gram-negative bacterial pathogens. The type III secretion system consists of cytoplasmic, transmembrane, and extracellular domains. The extracellular domain is a hollow needle protruding above the bacterial surface and is held within a basal body that traverses both bacterial membranes. Effector proteins are translocated, via this external needle, directly into host cells, where they subvert normal cell functions to aid infection. Physical contact with host cells initiates secretion and leads to formation of a pore, thought to be contiguous with the needle channel, in the host-cell membrane. Here, we report the crystal structure of the Shigella flexneri needle subunit MxiH and a complete model for the needle assembly built into our three-dimensional EM reconstruction. The model, combined with mutagenesis data, reveals that signaling of host-cell contact is relayed through the needle via intersubunit contacts and suggests a mode of binding for a tip complex.

Needle segmentation using 3D Hough transform in 3D TRUS guided prostate transperineal therapy

Energy Technology Data Exchange (ETDEWEB)

Qiu Wu [Department of Biomedical Engineering, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario N6A 5K8 (Canada); Yuchi Ming; Ding Mingyue [Department of Biomedical Engineering, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Tessier, David; Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada)

2013-04-15

Purpose: Prostate adenocarcinoma is the most common noncutaneous malignancy in American men with over 200 000 new cases diagnosed each year. Prostate interventional therapy, such as cryotherapy and brachytherapy, is an effective treatment for prostate cancer. Its success relies on the correct needle implant position. This paper proposes a robust and efficient needle segmentation method, which acts as an aid to localize the needle in three-dimensional (3D) transrectal ultrasound (TRUS) guided prostate therapy. Methods: The procedure of locating the needle in a 3D TRUS image is a three-step process. First, the original 3D ultrasound image containing a needle is cropped; the cropped image is then converted to a binary format based on its histogram. Second, a 3D Hough transform based needle segmentation method is applied to the 3D binary image in order to locate the needle axis. The position of the needle endpoint is finally determined by an optimal threshold based analysis of the intensity probability distribution. The overall efficiency is improved through implementing a coarse-fine searching strategy. The proposed method was validated in tissue-mimicking agar phantoms, chicken breast phantoms, and 3D TRUS patient images from prostate brachytherapy and cryotherapy procedures by comparison to the manual segmentation. The robustness of the proposed approach was tested by means of varying parameters such as needle insertion angle, needle insertion length, binarization threshold level, and cropping size. Results: The validation results indicate that the proposed Hough transform based method is accurate and robust, with an achieved endpoint localization accuracy of 0.5 mm for agar phantom images, 0.7 mm for chicken breast phantom images, and 1 mm for in vivo patient cryotherapy and brachytherapy images. The mean execution time of needle segmentation algorithm was 2 s for a 3D TRUS image with size of 264 Multiplication-Sign 376 Multiplication-Sign 630 voxels. Conclusions

Comparison of cutting and pencil-point spinal needle in spinal anesthesia regarding postdural puncture headache

Science.gov (United States)

Xu, Hong; Liu, Yang; Song, WenYe; Kan, ShunLi; Liu, FeiFei; Zhang, Di; Ning, GuangZhi; Feng, ShiQing

2017-01-01

Abstract Background: Postdural puncture headache (PDPH), mainly resulting from the loss of cerebral spinal fluid (CSF), is a well-known iatrogenic complication of spinal anesthesia and diagnostic lumbar puncture. Spinal needles have been modified to minimize complications. Modifiable risk factors of PDPH mainly included needle size and needle shape. However, whether the incidence of PDPH is significantly different between cutting-point and pencil-point needles was controversial. Then we did a meta-analysis to assess the incidence of PDPH of cutting spinal needle and pencil-point spinal needle. Methods: We included all randomly designed trials, assessing the clinical outcomes in patients given elective spinal anesthesia or diagnostic lumbar puncture with either cutting or pencil-point spinal needle as eligible studies. All selected studies and the risk of bias of them were assessed by 2 investigators. Clinical outcomes including success rates, frequency of PDPH, reported severe PDPH, and the use of epidural blood patch (EBP) were recorded as primary results. Results were evaluated using risk ratio (RR) with 95% confidence interval (CI) for dichotomous variables. Rev Man software (version 5.3) was used to analyze all appropriate data. Results: Twenty-five randomized controlled trials (RCTs) were included in our study. The analysis result revealed that pencil-point spinal needle would result in lower rate of PDPH (RR 2.50; 95% CI [1.96, 3.19]; P < 0.00001) and severe PDPH (RR 3.27; 95% CI [2.15, 4.96]; P < 0.00001). Furthermore, EBP was less used in pencil-point spine needle group (RR 3.69; 95% CI [1.96, 6.95]; P < 0.0001). Conclusions: Current evidences suggest that pencil-point spinal needle was significantly superior compared with cutting spinal needle regarding the frequency of PDPH, PDPH severity, and the use of EBP. In view of this, we recommend the use of pencil-point spinal needle in spinal anesthesia and lumbar puncture. PMID:28383416

Needle segmentation using 3D Hough transform in 3D TRUS guided prostate transperineal therapy

International Nuclear Information System (INIS)

Qiu Wu; Yuchi Ming; Ding Mingyue; Tessier, David; Fenster, Aaron

2013-01-01

Purpose: Prostate adenocarcinoma is the most common noncutaneous malignancy in American men with over 200 000 new cases diagnosed each year. Prostate interventional therapy, such as cryotherapy and brachytherapy, is an effective treatment for prostate cancer. Its success relies on the correct needle implant position. This paper proposes a robust and efficient needle segmentation method, which acts as an aid to localize the needle in three-dimensional (3D) transrectal ultrasound (TRUS) guided prostate therapy. Methods: The procedure of locating the needle in a 3D TRUS image is a three-step process. First, the original 3D ultrasound image containing a needle is cropped; the cropped image is then converted to a binary format based on its histogram. Second, a 3D Hough transform based needle segmentation method is applied to the 3D binary image in order to locate the needle axis. The position of the needle endpoint is finally determined by an optimal threshold based analysis of the intensity probability distribution. The overall efficiency is improved through implementing a coarse-fine searching strategy. The proposed method was validated in tissue-mimicking agar phantoms, chicken breast phantoms, and 3D TRUS patient images from prostate brachytherapy and cryotherapy procedures by comparison to the manual segmentation. The robustness of the proposed approach was tested by means of varying parameters such as needle insertion angle, needle insertion length, binarization threshold level, and cropping size. Results: The validation results indicate that the proposed Hough transform based method is accurate and robust, with an achieved endpoint localization accuracy of 0.5 mm for agar phantom images, 0.7 mm for chicken breast phantom images, and 1 mm for in vivo patient cryotherapy and brachytherapy images. The mean execution time of needle segmentation algorithm was 2 s for a 3D TRUS image with size of 264 × 376 × 630 voxels. Conclusions: The proposed needle segmentation

Needle based sensors for the continuous Ischemia-Hypoxia monitoring

Energy Technology Data Exchange (ETDEWEB)

Dulay, S.; Bogachan Tahirbegi, I.; Mir, M.; Samitier, J.

2016-07-01

The development of miniaturized, implantable chemical sensors that can be employed for real-time monitoring of clinically important species, such as pH, O2, and CO2, Na+, K+ and Ca2+; glucose; lactate among other biochemical molecules remain as one of the great challenges in analytical and biomedical science. Ischemia-Hypoxia (IH) is a condition of reduced oxygen and nutrient supply to the tissue. This lack of perfusion could damage the tissue and if this tissue conditions are prolonged it could led to tissue necrosis. Therefore, IH monitoring is very valuable during surgical procedures. When the tissue is under IH conditions, there is a decrease in the oxygen and glucose available to the tissue as well as a decrease in the removal of CO2 due to inadequate blood flow. In this conditions, there is a ATP cell energy reduction and as a consequence the ions are not pumped properly and intracellular and extracellular concentrations of certain ions such as sodium (Na+), potassium (K+) and chloride (Cl-) shift, leading to abnormal ion concentration within the cells. The array sensor that our group is developing will be harmless, inexpensive, portable, and short response time using needle based electrodes. The prototype array with a total 10 mm diameter when housed was designed for being introduced by gastroendoscopy inside the stomach. (Author)

Image Analytical Approach for Needle-Shaped Crystal Counting and Length Estimation

DEFF Research Database (Denmark)

Wu, Jian X.; Kucheryavskiy, Sergey V.; Jensen, Linda G.

2015-01-01

Estimation of nucleation and crystal growth rates from microscopic information is of critical importance. This can be an especially challenging task if needle growth of crystals is observed. To address this challenge, an image analytical method for counting of needle-shaped crystals and estimating...

Pinus nigra and Pinus pinaster needles as passive samplers of polycyclic aromatic hydrocarbons

International Nuclear Information System (INIS)

Piccardo, Maria Teresa; Pala, Mauro; Bonaccurso, Bruna; Stella, Anna; Redaelli, Anna; Paola, Gaudenzio; Valerio, Federico

2005-01-01

Nine polycyclic aromatic hydrocarbons (PAHs) were analysed in pine needles of different ages (from 6 to 30 months) collected from two species, Pinus nigra and Pinus pinaster, in seven sites located along a transect from a suburban to a rural area of Genoa (Italy). In all sites and for both species, concentrations of more volatile PAHs (phenanthrene, anthracene, fluoranthene, pyrene) were higher than those for other less volatile PAHs, which are preferentially sorbed to airborne particulates (benzo[a]anthracene, chrysene, benzofluoranthenes, benzo[a]pyrene). Concentrations of total PAHs found in P. nigra in the rural sites were, on the average, 2.3 times higher than those in P. pinaster growing nearby. In both pine species, concentrations of volatile PAHs increased according to needle age. Annual trends of other PAHs were more variable, with a general decrease in older needles. P. pinaster needles are shown to be more reliable passive samplers, since they are more resistant to plant diseases, and considerable variation in PAH concentration was observed in P. nigra needles with moulds and fungi. - The suitability of the pine needles as passive air samplers for persistent trace organics is demonstrated

Pinus nigra and Pinus pinaster needles as passive samplers of polycyclic aromatic hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Piccardo, Maria Teresa [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy)]. E-mail: chimamb@istge.it; Pala, Mauro [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Bonaccurso, Bruna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Stella, Anna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Redaelli, Anna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Paola, Gaudenzio [Botany Department, Genoa University, C.so Dogali 1 canc., 16136 Genova (Italy); Valerio, Federico [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy)

2005-01-01

Nine polycyclic aromatic hydrocarbons (PAHs) were analysed in pine needles of different ages (from 6 to 30 months) collected from two species, Pinus nigra and Pinus pinaster, in seven sites located along a transect from a suburban to a rural area of Genoa (Italy). In all sites and for both species, concentrations of more volatile PAHs (phenanthrene, anthracene, fluoranthene, pyrene) were higher than those for other less volatile PAHs, which are preferentially sorbed to airborne particulates (benzo[a]anthracene, chrysene, benzofluoranthenes, benzo[a]pyrene). Concentrations of total PAHs found in P. nigra in the rural sites were, on the average, 2.3 times higher than those in P. pinaster growing nearby. In both pine species, concentrations of volatile PAHs increased according to needle age. Annual trends of other PAHs were more variable, with a general decrease in older needles. P. pinaster needles are shown to be more reliable passive samplers, since they are more resistant to plant diseases, and considerable variation in PAH concentration was observed in P. nigra needles with moulds and fungi. - The suitability of the pine needles as passive air samplers for persistent trace organics is demonstrated.

Diagnostic accuracy of lymphoma established by fine-needle aspiration cytological biopsy

Science.gov (United States)

Delyuzar; Amir, Z.; Suryadi, D.

2018-03-01

Based on Globocan data in 2012, it is estimated that about 14,495 Indonesians suffer from lymphoma, both Hodgkin’s lymphoma, and non-Hodgkin’s lymphoma. Some areas of specialization still doubt the accuracy of cytology diagnosis of fine needle aspiration biopsy.This study is a diagnostic test with a cross sectional analytic design to see how the cytology diagnostic accuracy of fine needle aspiration aspirate in lymphoma. It was in Department of Anatomical Pathology Faculty of Medicine USU, Haji Adam Malik Hospital, Dr.Pirngadi hospital, or private clinic in Medan. Peripheral cytology technique biopsy of fine needle aspiration on lymph node subsequently stained with Giemsa, when the cytology of lymphoma is obtained and confirmed by histopathologic examination. Cytology and histopathologic examination will be tested by Diagnostic Test and assessed for its sensitivity and specificity. The diagnostic of lymphoma cytology provides 93.33% sensitivity and 92.31% specificity when confirmed by histopathological examination. Positive predictive value and negative predictive value of 96.55% and 85.71% respectively. In conclusion, the cytology of fine needle aspiration biopsy is accurate enough to be used as a diagnostic tool, so it is advisable to establish a lymphoma diagnosis to perform a needle aspiration biopsy examination.

Characterization of ultrasound elevation beamwidth artifacts for prostate brachytherapy needle insertion

International Nuclear Information System (INIS)

Peikari, Mohammad; Chen, Thomas Kuriran; Lasso, Anras; Heffter, Tamas; Fichtinger, Gabor; Burdette, Everette C.

2012-01-01

Purpose: Ultrasound elevation beamwidth leads to image artifacts and uncertainties in localizing objects (such as a surgical needle) in ultrasound images. The authors examined the clinical significance of errors caused by elevation beamwidth artifacts and imaging parameters in needle insertion procedures. Methods: Beveled prostate brachytherapy needles were inserted through all holes of a grid template under real-time transrectal ultrasound (TRUS) guidance. The needle tip position as indicated by the TRUS image was compared to their observed physical location. A new device was developed to measure the ultrasound elevation beamwidth. Results: Imaging parameters of the TRUS scanner have direct impact on the localization error ranging from 0.5 up to 4 mm. The smallest localization error was observed laterally close to the center of the grid template and axially within the beam's focal zone. Largest localization error occurs laterally around both sides of the grid template and axially within the beam's far field. The authors also found that the localization errors vary with both lateral and elevation offsets. Conclusions: The authors found properly adjusting the TRUS imaging settings to lower the ultrasound gain and power effectively minimized the appearance of elevation beamwidth artifacts and in turn reduced the localization errors of the needle tip.

Electrostatic Assembly of Nanomaterials for Hybrid Electrodes and Supercapacitors

Science.gov (United States)

Hammond, Paula

2015-03-01

Electrostatic assembly methods have been used to generate a range of new materials systems of interest for electrochemical energy and storage applications. Over the past several years, it has been demonstrated that carbon nanotubes, metals, metal oxides, polymeric nanomaterials, and biotemplated materials systems can be incorporated into ultrathin films to generate supercapacitors and battery electrodes that illustrate significant energy density and power. The unique ability to control the incorporation of such a broad range of materials at the nanometer length scale allows tailoring of the final properties of these unique composite systems, as well as the capability of creating complex micron-scale to nanoporous morphologies based on the scale of the nanomaterial that is absorbed within the structure, or the conditions of self-assembly. Recently we have expanded these capabilities to achieve new electrodes that are templated atop electrospun polmer fiber scaffolds, in which the polymer can be selectively removed to achieve highly porous materials. Spray-layer-by-layer and filtration methods of functionalized multiwall carbon nanotubes and polyaniline nanofibers enable the generation of electrode systems with unusually high surface. Incorporation of psuedocapacitive nanoparticles can enhance capacitive properties, and other catalytic or metallic nanoparticles can be implemented to enhance electrochemical or catalytic function.

Serum Chrome levels sampled with steel needle vs. plastic IV cannula

DEFF Research Database (Denmark)

Penny, Jeannette Østergaard; Overgaard, Søren

2010-01-01

. This study aimed to test that theory. Method: We compared serum chromium values for two sampling methods, steel needle and IV plastic cannula, as well as sampling sequence in 16 healthy volunteers. Results: We found statistically significant chromium contamination from the steel needle with mean differences......  Modern Metal-on-metal (MoM) joint articulations releases metal ions to the body. Research tries to establish how much this elevates metal ion levels and whether it causes adverse effects. The steel needle that samples the blood may introduce additional chromium to the sample thereby causing bias...... between the two methods of 0.073 ng/mL, for the first sample, and 0.033 ng/mL for the second. No difference was found between the first and second plastic sample. The first steel needle sample contained an average of 0.047 ng/mL more than the second. This difference was only borderline significant...

Cobalt phthalocyanine modified electrodes utilised in electroanalysis: nano-structured modified electrodes vs. bulk modified screen-printed electrodes.

Science.gov (United States)

Foster, Christopher W; Pillay, Jeseelan; Metters, Jonathan P; Banks, Craig E

2014-11-19

Cobalt phthalocyanine (CoPC) compounds have been reported to provide electrocatalytic performances towards a substantial number of analytes. In these configurations, electrodes are typically constructed via drop casting the CoPC onto a supporting electrode substrate, while in other cases the CoPC complex is incorporated within the ink of a screen-printed sensor, providing a one-shot economical and disposable electrode configuration. In this paper we critically compare CoPC modified electrodes prepared by drop casting CoPC nanoparticles (nano-CoPC) onto a range of carbon based electrode substrates with that of CoPC bulk modified screen-printed electrodes in the sensing of the model analytes L-ascorbic acid, oxygen and hydrazine. It is found that no "electrocatalysis" is observed towards L-ascorbic acid using either of these CoPC modified electrode configurations and that the bare underlying carbon electrode is the origin of the obtained voltammetric signal, which gives rise to useful electroanalytical signatures, providing new insights into literature reports where "electrocatalysis" has been reported with no clear control experiments undertaken. On the other hand true electrocatalysis is observed towards hydrazine, where no such voltammetric features are witnessed on the bare underlying electrode substrate.

Development of a high frequency single-element ultrasound needle transducer for anesthesia delivery

Science.gov (United States)

Ameri, Golafsoun; Son, Jungik; Liang, Jingwei; Foster, F. Stuart; Ganapathy, Sugantha; Peters, Terry M.

2017-03-01

Epidural anesthesia is one of the most commonly used and yet challenging techniques employed for pain management and anesthesia delivery. The major complications of this procedure are due to accidental dural puncture, with an incidence of 1-3%, which could lead to both temporary and irreversible permanent neurological complications. Needle placement under ultrasound (US) guidance has received increasing interest for improving needle placement accuracy. However, poor needle visibility in US, difficulties in displaying relevant anatomical structure such as dura mater due to attenuation and bone shadowing, and image interpretation variability among users pose significant hurdles for any US guidance system. As a result, US guidance for epidural injections has not been widely adopted for everyday use for the performance of neuraxial blocks. The difficulties in localizing the ligamentum flavum and dura with respect to the needle tip can be addressed by integrating A-mode US, provided by a single-element transducer at the needle tip, into the B-mode US guidance system. We have taken the first steps towards providing such a guidance system. Our goal is to improve the safety of this procedure with minimal changes to the clinical workflow. This work presents the design and development of a 20 MHz single-element US transducer housed at the tip of a 19 G needle hypodermic tube, which can fit inside an epidural introducer needle. In addition, the results from initial transducer characterization tests and performance evaluation of the transducer in a euthanized porcine model are provided.

Improvements to the Processing and Characterization of Needled Composite Laminates

Science.gov (United States)

2014-01-01

the automated processing equipment are shown and discussed. The modifications allow better spatial control at the penetration sites and the ability... automated processing equipment are shown and discussed. The modifications allow better spatial control at the penetration sites and the ability to...semi- automated processing equipment, commercial off-the-shelf (COTS) needles and COTS aramid mat designed for other applications. Needled material

Ex Vivo Experiment of Saline-Enhanced Hepatic Bipolar Radiofrequency Ablation with a Perfused Needle Electrode: Comparison with Conventional Monopolar and Simultaneous Monopolar Modes

International Nuclear Information System (INIS)

Lee, Jeong Min; Kim, Se Hyung; Han, Joon Koo; Sohn, Kyu Li; Choi, Byung Ihn

2005-01-01

The purpose of this study was to validate the saline-enhanced bipolar radiofrequency ablation (RFA) technique using a perfused electrode to increase RF-created coagulation necrosis, to compare that technique with monopolar RFAs and to find appropriate concentrations and volumes of perfused NaCl solution for the bipolar RFA. A total of 90 ablations were performed in explanted bovine livers. In the initial experiments to determine appropriate conditions for bipolar RFA, we created five thermal ablation zones in each condition, with instillations of varied concentrations (0.9-36%) or injection rates (30 mL/hr-120 mL/hr) of NaCl solution. After placement of one or two 16-gauge open-perfused electrodes into bovine livers, the NaCl solution was instilled into the tissue through the electrode. In the second part of the study, 10 ablation zones were created using one or two perfused electrodes for each of five groups under different conditions: a conventional monopolar mode with 0.9% NaCl solution (group A) or with 6% NaCl solution (group B), a simultaneous monopolar mode with 6% NaCl solution (group C) and a bipolar mode with 6% NaCl solution (groups D and E). RF was applied to each electrode for 20 min in groups A, B, C, and E, or for 10 min in group D. During RFA, we measured the tissue temperature 15 mm from the electrode. The temperature changes during the RFA and the dimensions of the ablation zones were compared among the groups. Bipolar RFA created larger short-axis diameters of coagulation necrosis with 6% NaCl solution (35.8 ± 15 mm) than with 0.9% NaCl solution (17 ± 9.7 mm) (P 0.05): 31.0 ± 5.4 mm (group A); 28.8 ± 3.8 mm (group B); 25.5 ± 6.4 mm (group C); 32.6 ± 4.2 mm (group D); 49.4 ± 5.0 mm (group E). Bipolar RFA with instillation of 6% NaCl solution through an open perfusion system demonstrates better efficacy in creating a larger ablation zone than does conventional or simultaneous monopolar modes at the various times examined. Therefore

Painful percutaneous transthoracic needle biopsy of Schwannoma: a case report

International Nuclear Information System (INIS)

Kim, Sung Hoon; Chun, Kyung Ah; Kim, Young Joo; Park, Seog Hee; Shin, Kyung Sub; Lee, Eun Jung

1995-01-01

Percutaneous aspiration needle biopsy of the intrathoracic disease is a safe, easy, and accurate diagnostic method. It usually causes mild pain or discomfort during the procedure. We had a patient who complained of severe sharp pain, well localized at the biopsy site of the target mass during CT-guided transthoracic aspiration biopsy. It was pathologically confirmed as an intrathoracic schwannoma after special staining. To our knowledge, there has been no published report of such a painful percutaneous needle biopsy in a patient with schwannoma in Korea. Two cases were reported in other radiologic journals. The severe sharp pain developed during the transthoracic aspiration needle biopsy is a reliable sign of neurogenic tumor, therefore the participating radiologist should recommend specific immumochemical stain for neurogenic tumor to pathologist

Two-dimensional mapping of needle visibility with linear and curved array for ultrasound-guided interventional procedure

Science.gov (United States)

Susanti, Hesty; Suprijanto, Kurniadi, Deddy

2018-02-01

Needle visibility in ultrasound-guided technique has been a crucial factor for successful interventional procedure. It has been affected by several factors, i.e. puncture depth, insertion angle, needle size and material, and imaging technology. The influences of those factors made the needle not always well visible. 20 G needles of 15 cm length (Nano Line, facet) were inserted into water bath with variation of insertion angles and depths. Ultrasound measurements are performed with BK-Medical Flex Focus 800 using 12 MHz linear array and 5 MHz curved array in Ultrasound Guided Regional Anesthesia mode. We propose 3 criteria to evaluate needle visibility, i.e. maximum intensity, mean intensity, and the ratio between minimum and maximum intensity. Those criteria were then depicted into representative maps for practical purpose. The best criterion candidate for representing the needle visibility was criterion 1. Generally, the appearance pattern of the needle from this criterion was relatively consistent, i.e. for linear array, it was relatively poor visibility in the middle part of the shaft, while for curved array, it is relatively better visible toward the end of the shaft. With further investigations, for example with the use of tissue-mimicking phantom, the representative maps can be built for future practical purpose, i.e. as a tool for clinicians to ensure better needle placement in clinical application. It will help them to avoid the "dead" area where the needle is not well visible, so it can reduce the risks of vital structures traversing and the number of required insertion, resulting in less patient morbidity. Those simple criteria and representative maps can be utilized to evaluate general visibility patterns of the needle in vast range of needle types and sizes in different insertion media. This information is also important as an early investigation for future research of needle visibility improvement, i.e. the development of beamforming strategies and

Needle path planning and steering in a three-dimensional non-static environment using two-dimensional ultrasound images

Science.gov (United States)

Vrooijink, Gustaaf J.; Abayazid, Momen; Patil, Sachin; Alterovitz, Ron; Misra, Sarthak

2015-01-01

Needle insertion is commonly performed in minimally invasive medical procedures such as biopsy and radiation cancer treatment. During such procedures, accurate needle tip placement is critical for correct diagnosis or successful treatment. Accurate placement of the needle tip inside tissue is challenging, especially when the target moves and anatomical obstacles must be avoided. We develop a needle steering system capable of autonomously and accurately guiding a steerable needle using two-dimensional (2D) ultrasound images. The needle is steered to a moving target while avoiding moving obstacles in a three-dimensional (3D) non-static environment. Using a 2D ultrasound imaging device, our system accurately tracks the needle tip motion in 3D space in order to estimate the tip pose. The needle tip pose is used by a rapidly exploring random tree-based motion planner to compute a feasible needle path to the target. The motion planner is sufficiently fast such that replanning can be performed repeatedly in a closed-loop manner. This enables the system to correct for perturbations in needle motion, and movement in obstacle and target locations. Our needle steering experiments in a soft-tissue phantom achieves maximum targeting errors of 0.86 ± 0.35 mm (without obstacles) and 2.16 ± 0.88 mm (with a moving obstacle). PMID:26279600

Chondromalacia patellae treated by warming needle and rehabilitation training.

Science.gov (United States)

Qiu, Ling; Zhang, Min; Zhang, Ji; Gao, Le-Nv; Chen, Da-wei; Liu, Jun; She, Jia-yi; Wang, Ling; Yu, Jin-yan; Huang, Le-ping; Bai, Yang

2009-06-01

To observe the effect of warming needle combined with rehabilitation training on chondromalacia patellae in a randomized controlled trial. The 92 cases were randomly divided into a treatment group treated by warming needle plus rehabilitation training (47 cases) and a control group treated by medication plus rehabilitation training (45 cases), and the therapeutic effect was compared after 20 sessions. The pain was relieved more obviously in the treatment group than in the control group (P chondromalacia patellae.

Indentation and needle insertion properties of the human eye.

Science.gov (United States)

Matthews, A; Hutnik, C; Hill, K; Newson, T; Chan, T; Campbell, G

2014-07-01

Characterization of the biomechanical properties of the human eye has a number of potential utilities. One novel purpose is to provide the basis for development of suitable tissue-mimicking material. The purpose of this study was to determine the indentation and needle insertion characteristics on human eye globes and tissue strips. An indenter assessed the elastic response of human eye globes and tissue strips under increasing compressive loads. Needle insertion determined the force (N) needed to penetrate various areas of the eye wall. The results demonstrated that globes underwent slightly greater indentation at the midline than at the central cornea, and corneal strips indented twofold more than scleral strips, although neither difference was significant (P=0.400 and P=0.100, respectively). Significant differences were observed among various areas of needle insertion (Phuman eye construct with potential utility as a model for use in ophthalmology research and surgical teaching.

Presenting hydrothorax predicts failure of needle aspiration in primary spontaneous pneumothorax.

Science.gov (United States)

Wu, Kwok Kei; Lui, Chun Tat; Ho, Chik Leung; Tsui, Kwok Leung; Fung, Hin Tat

2016-06-01

The objective was to evaluate if existence of hydrothorax in initial chest radiograph predicts treatment outcome in patients with primary spontaneous pneumothorax who received needle thoracostomy. This is a retrospective cohort study carried out from January 2011 to August 2014 in 1 public hospital in Hong Kong. All consecutive adult patients aged 18years or above who attended the emergency department with the diagnosis of primary spontaneous pneumothorax with needle aspiration performed as primary treatment were included. Age, smoking status, size of pneumothorax, previous history of pneumothorax, aspirated gas volume and presence of hydropneumothorax in initial radiograph were included in the analysis. The outcome was success or failure of the needle aspiration. Logistic regression was used to identify the predicting factors of failure of needle aspiration. There were a total of 127 patients included. Seventy-three patients (57.5%) were successfully treated with no recurrence upon discharge. Among 54 failure cases, 13 patients (10.2%) failed immediately after procedure as evident by chest radiograph and required second treatment. Forty-one patients (32.3%) failed upon subsequent chest radiographs. Multivariate logistic regression showed factors independently associated with the failure of needle aspiration, which included hydropneumothorax in the initial radiograph (odds ratio [OR]=4.47 [1.56i12.83], P=.005), previous history of pneumothorax (OR=3.92 [1.57-9.79], P=.003), and large size of pneumothorax defined as apex-to-cupola distance ≥5cm (OR=2.75 [1.21-6.26], P=.016). Hydropneumothorax, previous history of pneumothorax, and large size were independent predictors of failure of needle aspiration in treatment of primary spontaneous pneumothorax. Copyright © 2016 Elsevier Inc. All rights reserved.

Multi hollow needle to plate plasmachemical reactor for pollutant decomposition

International Nuclear Information System (INIS)

Pekarek, S.; Kriha, V.; Viden, I.; Pospisil, M.

2001-01-01

Modification of the classical multipin to plate plasmachemical reactor for pollutant decomposition is proposed in this paper. In this modified reactor a mixture of air and pollutant flows through the needles, contrary to the classical reactor where a mixture of air and pollutant flows around the pins or through the channel plus through the hollow needles. We give the results of comparison of toluene decomposition efficiency for (a) a reactor with the main stream of a mixture through the channel around the needles and a small flow rate through the needles and (b) a modified reactor. It was found that for similar flow rates and similar energy deposition, the decomposition efficiency of toluene was increased more than six times in the modified reactor. This new modified reactor was also experimentally tested for the decomposition of volatile hydrocarbons from gasoline distillation range. An average efficiency of VOC decomposition of about 25% was reached. However, significant differences in the decomposition of various hydrocarbon types were observed. The best results were obtained for the decomposition of olefins (reaching 90%) and methyl-tert-butyl ether (about 50%). Moreover, the number of carbon atoms in the molecule affects the quality of VOC decomposition. (author)

Performance of combined clinical mammography and needle biopsy: a nationwide study from Denmark

DEFF Research Database (Denmark)

Jensen, Allan; Rank, Fritz; Dyreborg, Uffe

2006-01-01

Clinical mammography and needle biopsy are key tools for non-operative assessment of breast lesions. We evaluated the performance of all combined tests undertaken in Denmark in 2000. Clinical mammography and needle biopsy data were collected and linked to final cancer outcome, to determine sensit...... with a suspicious or malignant result indicated a high risk of cancer, and excisional diagnostic biopsy therefore still has an important role to play.......Clinical mammography and needle biopsy are key tools for non-operative assessment of breast lesions. We evaluated the performance of all combined tests undertaken in Denmark in 2000. Clinical mammography and needle biopsy data were collected and linked to final cancer outcome, to determine...

Mechanics of anesthetic needle penetration into human sciatic nerve.

Science.gov (United States)

Pichamuthu, Joseph E; Maiti, Spandan; Gan, Maria G; Verdecchia, Nicole M; Orebaugh, Steven L; Vorp, David A

2018-06-06

Nerve blocks are frequently performed by anesthesiologists to control pain. For sciatic nerve blocks, the optimal placement of the needle tip between its paraneural sheath and epineurial covering is challenging, even under ultrasound guidance, and frequently results in nerve puncture. We performed needle penetration tests on cadaveric isolated paraneural sheath (IPS), isolated nerve (IN), and the nerve with overlying paraneural sheath (NPS), and quantified puncture force requirement and fracture toughness of these specimens to assess their role in determining the clinical risk of nerve puncture. We found that puncture force (123 ± 17 mN) and fracture toughness (45.48 ± 9.72 J m -2 ) of IPS was significantly lower than those for NPS (1440 ± 161 mN and 1317.46 ± 212.45 Jm -2 , respectively), suggesting that it is not possible to push the tip of the block needle through the paraneural sheath only, without pushing it into the nerve directly, when the sheath is lying directly over the nerve. Results of this study provide a physical basis for tangential placement of the needle as the ideal situation for local anesthetic deposition, as it allows for the penetration of the sheath along the edge of the nerve without entering the epineurium. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparative study of decomposable and indecomposable biopsy needle in lung puncture biopsy

International Nuclear Information System (INIS)

Wang Bo; Sheng Zhanxin; Wen Yamin; Zhang Liping; Wen Zongqiu

2007-01-01

Objective: To contrast the clinical practice characteristics with decomposable and indecomposable biopsy needle in the CT-guided lung puncture biopsy. Methods: 50 patients with lung tumour carried on puncture biopsy under the CT guidance were divided in two groups randomly: Group A (25 examples): using the indecomposable BioPinceTM biopsy needle; Group B(25 examples): using the decomposable Precisa or Vitesse biopsy needle. The puncture biopsy organization quantity, the first time puncture success rate, the pathological diagnosis result and the incidence of puncture complication were compared in two groups. Results: More striped structures were gained obviously in group A than in group B: 24/25 and 11/25 respectively (P>0.05), The pathological diagnosis 'serious extrusion amoebocyte and nature undetermined' only occurred in group B. But the first time puncture success rate was lower in group A than in B: 52%(13/25) and 80%(20/25) respectively (P>0.05), The incidence of hemorrhage and pneumothorax in group A was higher slightly: 84% and 72%, 16% and 4% respectively (P>0.05). Conclusion: The indecomposable needle (BioPinceTM) was better in lung puncture biopsy, but the lower first time puncture success rate also increases the risk of operation and complication in some degree because of the structure of the needle. On the contrary, decomposable needle (the Precisa or the Vitesse) was not the best choice in lung puncture biopsy. But it had the original superiority, especially regarding the special patient such as patient with small tumour, thin thoracic wall, bad physique for its nimble operation. It is essential for us to use the two different types of biopsy needle rationally to enhance the level of CT-guided lung puncture biopsy. (authors)

Laparoscopic removal of a needle from the pancreas

Directory of Open Access Journals (Sweden)

Amit Jain

2013-01-01

Full Text Available Foreign bodies inside the pancreas are rare and usually occur after the ingestion of sharp objects like fish bone, sewing needle and toothpick. Most of the ingested foreign bodies pass spontaneously through the anus without being noticed but about 1% of them can perforate through the wall of stomach or duodenum to reach solid organs like pancreas or liver. Once inside the pancreas they can produce complications like abscess, pseudoaneurysm or pancreatits. Foreign bodies of pancreas should be removed by endoscopic or surgical methods. We hereby report our experience of successful removal one a sewing needle from pancreas.

Hematoma formation during breast core needle biopsy in women taking antithrombotic therapy.

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Chetlen, Alison L; Kasales, Claudia; Mack, Julie; Schetter, Susann; Zhu, Junjia

2013-07-01

The purpose of this study was to compare hematoma formation after breast core needle biopsy performed on patients undergoing and those not undergoing concurrent antithrombotic therapy. A prospective assessment of core needle biopsies (stereotactic, ultrasound guided, or MRI guided) performed on patients enrolled between September 2011 and July 2012 formed the basis of this study. Postprocedure mediolateral and craniocaudal mammograms were evaluated for the presence and size of hematomas. Patients were clinically evaluated for complications 24-48 hours after the procedure through telephone call or face-to-face consultation. Needle size, type of biopsy, and presence of hematoma and documented complications were correlated with use of antithrombotic agents (including aspirin, warfarin, clopidogrel, and daily nonsteroidal antiinflammatory medications). No clinically significant hematomas or bleeding complications were found. Eighty-nine of 617 (14.4%) non-clinically significant hematomas were detected on postprocedure mammograms. The probability of development of a non-clinically significant hematoma was 21.6% for patients taking antithrombotics and 13.0% for those not taking antithrombotics. Concurrent antithrombotic therapy and larger needle gauge were significant factors contributing to the probability of hematoma formation. The volume of the hematoma was not related to needle gauge or presence of antithrombotic therapy. No clinically significant hematomas were found. Because there are potential life-threatening risks to stopping antithrombotic therapy before breast biopsy, withholding antithrombotic therapy for core needle breast biopsy is not recommended because the incidence of non-clinically significant hematoma is low.

Reduction of Zygomatic Arch Isolated Fracture Using Ultra Sound and Needle Marking.

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Kim, Jun Sik; Park, Young Ji; Lee, Yoon Jung; Kim, Nam Gyun; Lee, Kyung Suk

2016-12-01

Zygomatic arch is a bony arch constituting the lateral midface, which consists of 25% of all midface fractures. There are a number of ways to evaluate the extent of zygomatic arch fracture. Some authors have reported successful treatment outcomes using ultrasound (U/S). To add to the previous methods, we have considered ways to accurately display the location of the fracture line while using U/S with 23 gauge needle marking. We introduce our method, which provided satisfactory results for reduction using a portable U/S, and it can evaluate the fracture line simultaneously when reduction of an isolated zygomatic arch fracture is necessary, and needle marking, which can easily point out the fracture line on U/S. We studied 21 patients with an isolated zygomatic arch fracture who underwent closed reduction using U/S and needle marking between 2013 and 2015. We achieved satisfactory results in all our cases with respect to reduction by using the Dingman elevator after performing a temporal approach incision, while confirming relative positioning between needle marking and zygomatic fracture at the same time, after insertion of a 23 gauge needle in the skin above the zygomatic arch fracture line parallel to it. We treated 21 patients with an isolated zygomatic arch fracture using U/S and the needle marking method, which provided satisfactory results because the extent of reduction of the fracture could be evaluated in real-time during the operation and exposure to radiation was reduced.

Cobalt Phthalocyanine Modified Electrodes Utilised in Electroanalysis: Nano-Structured Modified Electrodes vs. Bulk Modified Screen-Printed Electrodes

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Christopher W. Foster

2014-11-01

Full Text Available Cobalt phthalocyanine (CoPC compounds have been reported to provide electrocatalytic performances towards a substantial number of analytes. In these configurations, electrodes are typically constructed via drop casting the CoPC onto a supporting electrode substrate, while in other cases the CoPC complex is incorporated within the ink of a screen-printed sensor, providing a one-shot economical and disposable electrode configuration. In this paper we critically compare CoPC modified electrodes prepared by drop casting CoPC nanoparticles (nano-CoPC onto a range of carbon based electrode substrates with that of CoPC bulk modified screen-printed electrodes in the sensing of the model analytes L-ascorbic acid, oxygen and hydrazine. It is found that no “electrocatalysis” is observed towards L-ascorbic acid using either of these CoPC modified electrode configurations and that the bare underlying carbon electrode is the origin of the obtained voltammetric signal, which gives rise to useful electroanalytical signatures, providing new insights into literature reports where “electrocatalysis” has been reported with no clear control experiments undertaken. On the other hand true electrocatalysis is observed towards hydrazine, where no such voltammetric features are witnessed on the bare underlying electrode substrate.

Systematic review of long-term Xingnao Kaiqiao needling effcacy in ischemic stroke treatment

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Zhi-xin Yang

2015-01-01

CONCLUSION: The Xingnao Kaiqiao needling method has a better effect than control treatment in reducing disability rate. The long-term effect of Xingnao Kaiqiao needling against ischemic stroke is better than that of control treatment. However, the limitations of this study limit the strength of the conclusions. Randomized controlled trials with a strict, reasonable design, and multi-center, large-scale samples and follow-up are necessary to draw conclusions about Xingnao Kaiqiao needling.

Comparison of needles size in pediatric renal biopsy with sono-guided percutaneous-automated gun technique

International Nuclear Information System (INIS)

Kim, Jong Chul; Park, Jin Yong

1997-01-01

To compare the efficacy of a 20-gauge and an 18-gauge needle in sono-guided percutaneous automated gun biopsy for establishing the specific diagnosis of renal parenchymal disease in pediatric kidneys. In 60 pediatric patients with renal parenchymal diseases, percutaneous sono-guided gun biopsy was performed by an experienced radiologist. In two groups of 30 patients, regardless of their age, two needle passes were performed, using alternately an 18-gauge or a 20-gauge biopsy needle. The core of renal tissue thus obtained was examined with light, immunofluorescent or electron microscopy by the renal pathologist. The mean number of intact glomeruli of whole tissue core per biopsy, as seen on the light microscopy, and post-bioptic complications were compared between the two different needle size groups. The number (mean±1 standard deviation) of glomeruli obtained per biopsy was 17±8 in the 18-gauge needle group, and 14±5 in the 20-gauge group. Between two groups, there was no major post-bioptic complication requiring specific treatment, nor a statistically significant difference in the frequency of minor complications. Even though more glomeruli were obtained with an 18-gauge needle, the number obtained with a 20-gauge needle also permitted adequate pathologic examination. Both an 18-gauge and a 20-gauge needle may thus be suitable for renal biopsy in pediatric patients

Development of a nanowire based titanium needle probe sensor for glucose monitoring

Science.gov (United States)

Deshpande, Devesh C.

The need for continuous monitoring of various physiological functions such as blood glucose levels, neural functions and cholesterol levels has fostered the research and development of various schemes of biosensors to sense and help control the respective function. The needs of patients for sensors with minimal discomfort, longer life and better performance have necessitated the development towards smaller and more efficient sensors. In addition, the need for higher functionality from smaller sensors has led to the development of sensors with multiple electrodes, each electrode capable of sensing a different body function. Such multi-electrode sensors need to be fabricated using micro-fabrication processes in order to achieve precise control over the size, shape and placement of the electrodes. Multielectrode sensors fabricated using silicon and polymers have been demonstrated. One physiological function that attracts widespread interest is continuous glucose monitoring in our blood, since Diabetes affects millions of people all over the world. Significant deviations of blood glucose levels from the normal levels of 4-8 mM can cause fainting, coma and damage to the eyes, kidneys, nerves and blood vessels. For chronic patients, continuous monitoring of glucose levels is essential for accurate and timely treatment. A few continuous monitoring sensors are available in the market, but they have problems and cannot replace the strip type one-time glucose monitoring systems as yet. To address this need, large scale research efforts have been targeted towards continuous monitoring. The demand for higher accuracy and sensitivity has motivated researchers to evaluate the use of nanostructures in sensing. The large surface area-to-volume ratio of such structures could enable further miniaturization and push the detection limits, potentially enabling even single molecule detection. This research involved the development of a biocompatible titanium needle probe sensor for

Effect of body condition on consumption of pine needles (Pinus ponderosa) by beef cows.

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Pfister, J A; Panter, K E; Gardner, D R; Cook, D; Welch, K D

2008-12-01

We determined whether cows in low (LBC) or high body condition (HBC) would consume different amounts of green pine needles (Pinus ponderosa). Cows (mature; open Hereford and Hereford x Angus) were fed a maintenance basal diet (alfalfa pellets) for Exp. 1 and 2; during Exp. 3 and 4, cows were fed high-protein and high-energy diets, respectively. Experiment 5 was a grazing study on rangeland during winter in South Dakota; diets were determined by using bite counts. Mean BCS (1 = emaciated, 9 = obese) was 7.5 for HBC cows and <4.0 for LBC cows during the experiments. During Exp. 1, LBC cows consumed more (P = 0.001) pine needles than did HBC cows (5.5 +/- 0.25 vs. 1.0 +/- 0.14 g/kg of BW daily, respectively). During Exp. 2, there was a day x treatment interaction (P = 0.001) as LBC cows consumed variable, but greater, amounts of pine needles than did HBC cows (3.7 +/- 0.19 vs. 1.3 +/- 0.12 g/kg of BW daily, respectively). When fed a high-protein/low-energy diet, LBC cows ate more (P = 0.04) pine needles than did HBC cows. When fed a low-protein/high-energy diet, there was a day x treatment interaction (P = 0.001) because LBC cows consumed more pine needles than did HBC cows for the first 3 d of the study, and then consumption by LBC animals decreased during the last 4 d. These experiments suggest that the protein:energy ratio may be an important factor in the ability of cows to tolerate terpenes, and that cows were not able to sustain an increased quantity of needle consumption on a low-protein diet. During the 25-d grazing study, there was a day x treatment interaction (P = 0.001) as LBC animals selected more pine needles (up to 25% of daily bites) on some days compared with HBC cows. Weather influenced pine needle consumption because pine needle bites by LBC cows were related (r(2) = 0.60; P = 0.001) to days of greater snow depth and lower minimum daily temperatures. Both LBC and HBC cows increased selection of pine needles from trees during cold, snowy weather, but

Changes in the rumen bacterial microbiome of cattle exposed to ponderosa pine needles.

Science.gov (United States)

Welch, K D; Stonecipher, C A; Gardner, D R; Cook, D; Pfister, J A

2017-05-01

Consumption of ponderosa pine needles, as well as needles and bark from a number of other trees, can cause abortions in cattle. The abortifacient compounds in these trees are labdane resin acids, including isocupressic acid and agathic acid. Previous research has demonstrated that cattle conditioned to pine needles metabolize the labdane resin acids more quickly than naïve cattle. The results from that study indicated that changes had occurred in the rumen of conditioned cattle. Therefore, in this study, the changes that occurred in the rumen bacterial microflora of cattle during exposure to ponderosa pine needles were evaluated. Cattle were dosed with ground pine needles twice daily for 7 d. Rumen samples were collected on d 0, 3, 7, and 14 (7 d after treatment stopped) and ruminal bacterial microbiome analyses were performed. There were 372 different genera of bacteria identified in the rumen samples. Principal coordinate analysis indicated that there was a significant difference in the rumen bacterial composition between the time points. There were 18 genera that increased in abundance from d 0 to d 7. Twenty three genera decreased in abundance from d 0 to d 7. The results from this study demonstrated that exposure of cattle to pine needles caused a clear shift in the rumen microbiome composition. In general, this shift lasted less than 1 wk post exposure, which indicates that any prophylactic treatment to manipulate the ruminal metabolism of the abortifacient compounds in pine needles would need to be continuously administered to maintain the necessary microbial composition in the rumen.

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.

A major trade-off between structural and photosynthetic investments operative across plant and needle ages in three Mediterranean pines.

Science.gov (United States)

Kuusk, Vivian; Niinemets, Ülo; Valladares, Fernando

2018-04-01

Pine (Pinus) species exhibit extensive variation in needle shape and size between juvenile (primary) and adult (secondary) needles (heteroblasty), but few studies have quantified the changes in needle morphological, anatomical and chemical traits upon juvenile-to-adult transition. Mediterranean pines keep juvenile needles longer than most other pines, implying that juvenile needles play a particularly significant role in seedling and sapling establishment in this environment. We studied needle anatomical, morphological and chemical characteristics in juvenile and different-aged adult needles in Mediterranean pines Pinus halepensis Mill., Pinus pinea L. and Pinus nigra J. F. Arnold subsp. salzmannii (Dunal) Franco hypothesizing that needle anatomical modifications upon juvenile-to-adult transition lead to a trade-off between investments in support and photosynthetic tissues, and that analogous changes occur with needle aging albeit to a lower degree. Compared with adult needles, juvenile needles of all species were narrower with 1.6- to 2.4-fold lower leaf dry mass per unit area, and had ~1.4-fold thinner cell walls, but needle nitrogen content per dry mass was similar among plant ages. Juvenile needles also had ~1.5-fold greater mesophyll volume fraction, ~3-fold greater chloroplast volume fraction and ~1.7-fold greater chloroplast exposed to mesophyll exposed surface area ratio, suggesting overall greater photosynthetic activity. Changes in needle traits were similar in aging adult needles, but the magnitude was generally less than the changes upon juvenile to adult transition. In adult needles, the fraction in support tissues scaled positively with known ranking of species tolerance of drought (P. halepensis > P. pinea > P. nigra). Across all species, and needle and plant ages, a negative correlation between volume fractions of mesophyll and structural tissues was observed, manifesting a trade-off between biomass investments in different needle functions. These

[Exploration of acupoint combination and needling techniques in the reinforcing and reducing manipulation at different acupoints].

Science.gov (United States)

Dai, Qing; Sheng, Xiesun; Chen, Feng

2017-04-12

The reinforcing and reducing manipulation at different acupoints is a kind of acupuncture manipulations and has satisfactory clinical therapeutic effects, combined with a proper needling techniques. The reinforcing needling method is used in the upper and the reducing one in the lower, the distal acupoints are combined with the nearby acupoints. The local acupoints or adjcant acupoints of the affected area are regarded as the nearby acupoints, e.g. the acupoints in the upper. The distant acupoints and the acupoints on the hand and foot are named as distal acupoints, e.g. the acupoint in the lower. In the reinforcing manipulation, the needle is inserted shallowly along the running direction of meridian. In the reducing manipulation, the needle is inserted deeply and against the running direction of meridian. The yin - yang couple needling technique is used with the combination of the front- mu and back- shu points. In the first option, the reinforcing and reducing needling method with rotating technique is predominated at the front- mu points, while that with lifting and thrusting technique is at the back- shu points. In the second option, when needling the back- shu points, the needling sensation is transmitted along the transverse segment and far to the chest and abdomen. These two kinds of integration of acupoint combination and needling techniques display a certain clinical significance in improving the therapeutic effects of acupuncture.

Open magnetic resonance imaging using titanium-zirconium needles: improved accuracy for interstitial brachytherapy implants?

International Nuclear Information System (INIS)

Popowski, Youri; Hiltbrand, Emile; Joliat, Dominique; Rouzaud, Michel

2000-01-01

Purpose: To evaluate the benefit of using an open magnetic resonance (MR) machine and new MR-compatible needles to improve the accuracy of brachytherapy implants in pelvic tumors. Methods and Materials: The open MR machine, foreseen for interventional procedures, allows direct visualization of the pelvic structures that are to be implanted. For that purpose, we have developed MR- and CT-compatible titanium-zirconium (Ti-Zr) brachytherapy needles that allow implantations to be carried out under the magnetic field. In order to test the technical feasibility of this new approach, stainless steel (SS) and Ti-Zr needles were first compared in a tissue-equivalent phantom. In a second step, two patients implanted with Ti-Zr needles in the brachytherapy operating room were scanned in the open MR machine. In a third phase, four patients were implanted directly under open MR control. Results: The artifacts induced by both materials were significantly different, strongly favoring the Ti-Zr needles. The implantation in both first patients confirmed the excellent quality of the pictures obtained with the needles in vivo and showed suboptimal implant geometry in both patients. In the next 4 patients, the tumor could be punctured with excellent accuracy, and the adjacent structures could be easily avoided. Conclusion: We conclude that open MR using MR-compatible needles is a very promising tool in brachytherapy, especially for pelvic tumors

Fine-needle trucut biopsy versus fine-needle aspiration cytology with ultrasound guidance in the abdomen

International Nuclear Information System (INIS)

O'Connell, A.M.; Keeling, F.; Given, M.; Logan, M.; Lee, M.J.

2008-01-01

Historically, fine-needle aspiration cytology (FNAC) has varying sensitivity, specificity and accuracy in the diagnosis of abdominal lesions with a high insufficient sampling rate. We compared 20-G fine-needle trucut biopsy (FNTB) with FNAC results in the biopsy of solid abdominal tumours. A retrospective review of 171 (128x 20-G FNTB and 43x FNAC) ultrasound-guided biopsies of abdominal tumours on 157 patients (male : female 85:72, mean age 61.25 years) were carried out. One hundred and seventy-one biopsies were carried out: liver 109, pancreas 19, lumph node 10, omentum 5, right iliac fossa mass 6, adrenal 6 and others 16. An average of 2.06 and 1.97 passes (range 1-4) were carried out per FNTB and FNAC, respectively. A definitive diagnosis was made in 122/128 biopsies (95.3%) and 32/43 biopsies (74.4%) for FNTB and FNAC, respectively. Diagnoses consisted of metastatic liver disease (74/171), pancreatic adenocarcinoma (10/171), lymphoma (8/171) and others (33/171) and benign (29/171). No significant complications occurred in either group. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 100, 100, 50, 84.4 and 93.1, 100, 100, 60, 71.4 for FNTB and FNAC, respectively. A greater and more consistent positive diagnosis rate is yielded by 20-G FNTB (95.3%) that FNAC (74.4%). The diagnostic accuracy of FNTB is 84.4% cmopared with 69.8% for FNAC. A greater insufficient sampling rate occurs with FNAC (25.6%) than with FNTB (4.7%). For abdominal biopsy, 20-G FNTB needles have a much higher yield than FNAC with no increase in complications. FNTB is the preferred choice, particularly where cytological assistance at the time of biopsy is unavailable.

A spatial analysis of the physical and social environmental correlates of discarded needles.

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de Montigny, Luc; Moudon, Anne Vernez; Leigh, Barbara C; Kim, Sun-Young

2011-05-01

The role that the urban environment plays in influencing drug users' injection and needle disposal decisions is poorly understood. We identified potential attractors and deterrents of needle discarding, and then used a geographic information system (GIS) to quantify these factors for a neighborhood in Montréal, Canada. In multivariate logistic regression, discarded needles were found to have more associations with physical factors than with social factors. Visual exposure and proximity to a single-room occupancy hotel, a pay phone, an adult service or a pawnshop were important physical environmental predictors. These findings are discussed in relation to developing public health and urban design-based harm reduction approaches to needle discarding in public space. Copyright © 2011 Elsevier Ltd. All rights reserved.

MDCT-Guided Transthoracic Needle Aspiration Biopsy of the Lung Using the Transscapular Approach

International Nuclear Information System (INIS)

Rossi, Umberto G.; Seitun, Sara; Ferro, Carlo

2011-01-01

The purpose of this study is to report our preliminary experience using MDCT-guided percutaneous transthoracic needle aspiration biopsy using the transscapular approach in the upper posterolateral lung nodules, an area that it is difficult or hazardous to reach with the conventional approach. Five patients underwent CT-guided percutaneous transthoracic needle aspiration biopsy of the lung via the transscapular approach. A coaxial needle technique was used in all patients. Biopsy was successful in all patients. No major complications were encountered. One patient developed a minimal pneumothorax next to the lesion immediately after biopsy, which resolved spontaneously. MDCT-guided percutaneous transthoracic needle aspiration biopsy of the lung via the transscapular approach is an effective and safe procedure that reduces the risk of pneumothorax in selected patients.

[Percutaneous needle aponeurotomy for Dupuytren's disease].

Science.gov (United States)

Spies, C K; Müller, L P; Skouras, E; Bassemir, D; Hahn, P; Unglaub, F

2016-02-01

Percutaneous transverse aponeurotomy of the cord by using a hypodermic needle as a scalpel blade in order to improve function of the hand. Symptomatic flexion contracture with positive table top test caused by a single, palpable cord within the palm (primarily Tubiana stages I and II). Multiple, infiltrating or broad-based cords within the palm; irritated skin conditions; exclusive digital cord localization; recurrence after aponeurectomy; previous surgical intervention at the site of interest, digital nerve lesions; lack of patient compliance. Pinpoint surface anesthesia is obtained by injecting each portal area subdermally with 0.1 ml of local anesthetic. These applications start from distally to proximally within the palm while the most distal injection site is located proximal to the distal palm crease. Then the needle tip is introduced perpendicular to the cord. Sawing movements through the cord are performed transversely. While passively extending the contracted finger, the cord is held under tension which guarantees safe cutting. Patients are encouraged to report immediate pain sensation or numbness in order to prevent injuries to neurovascular structures and active finger flexion excludes tendon lesions during the procedure. Introducing the needle tip may be performed at several sites along the cord, if necessary, from distal to proximal at least 5 mm apart with prior pinpoint surface anesthesia. Finally, cautious passive stretching may be done after each release. Bandaging allowing immediate motion; application of a hand-based extension splint-glove during the night for 3-6 months. Recurrence rate was 53% in 15 retrospectively examined patients after a mean interval of 40 months postoperatively.

Cannula Versus Sharp Needle for Placement of Soft Tissue Fillers: An Observational Cadaver Study.

Science.gov (United States)

van Loghem, Jani A J; Humzah, Dalvi; Kerscher, Martina

2017-12-13

Soft-tissue fillers have become important products for facial rejuvenation. Deep fat compartments and facial bones lose volume during the natural aging process. For the most natural-looking results, deep volumetric injections at strategic sites are therefore preferred. Supraperiosteal placement is performed with a sharp needle or a non-traumatic cannula. The primary objective was to determine whether there is a difference in precision between supraperiosteal placement with a sharp needle compared with a non-traumatic cannula in cadaver specimens. A secondary objective was to analyze the safety profiles of both injection techniques. Cadaver heads were injected with dye material and soft-tissue fillers at multiple aesthetic facial sites on the supraperiosteum and subsequently dissected for observation of dye and filler placement. The non-traumatic cannula technique resulted in product being confined to the deep anatomic layers. In contrast, with the sharp needle technique, material was placed in multiple anatomic layers, from the periosteum to more superficial skin layers. For both techniques results were consistent for all facial sites. Although direct extrapolation from cadavers to the in vivo situation cannot be made, cannulae showed more precision in placement of product. With the sharp needle, the material was injected on the periosteum, and then migrated in a retrograde direction along the trajectory of the needle path, ending up in multiple anatomic layers. The sharp needle technique also showed a higher complication risk with intra-arterial injection occurring, even though the needle tip was positioned on the periosteum and the product was injected with the needle in constant contact with the periosteum. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com