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Sample records for scanning fiber endoscope

  1. Near-infrared dental imaging using scanning fiber endoscope

    Science.gov (United States)

    Zhou, Yaxuan; Lee, Robert; Sadr, Alireza; Seibel, Eric J.

    2018-02-01

    Near-infrared (NIR) wavelength range of 1300-1500nm has the potential to outperform or augment other dental imaging modalities such as fluorescence imaging, owing to its lower scattering coefficient in enamel and trans- parency on stains and non-cariogenic plaque. However, cameras in this wavelength range are bulky and expensive, which lead to difficulties for in-vivo use and commercialization. Thus, we have proposed a new imaging device combining the scanning fiber endoscopy (SFE) and NIR imaging technology. The NIR SFE system has the advantage of miniature size (1.6 mm), flexible shaft, video frame rate (7Hz) and expandable wide field-of-view (60 degrees). Eleven extracted human teeth with or without occlusal caries were scanned by micro-computed X-ray tomography (micro-CT) to obtain 3D micro-CT images, which serve as the standard for comparison. NIR images in reflection mode were then taken on all the occlusal surfaces, using 1310nm super luminescent diode and 1460nm laser diode respectively. Qualitative comparison was performed between near-infrared im- ages and micro-CT images. Enamel demineralization in NIR appeared as areas of increased reflectivity, and distinguished from non-carious staining at the base of occlusal fissures or developmental defects on cusps. This preliminary work presented proof for practicability of combining NIR imaging technology with SFE for reliable and noninvasive dental imaging with miniaturization and low cost.

  2. Laser scanning endoscope via an imaging fiber bundle for fluorescence imaging

    Science.gov (United States)

    Yeboah, Lorenz D.; Nestler, Dirk; Steiner, Rudolf W.

    1994-12-01

    Based on a laser scanning endoscope via an imaging fiber bundle, a new approach for a tumor diagnostic system has been developed to assist physicians in the diagnosis before the actual PDT is carried out. Laser induced, spatially resolved fluorescence images of diseased tissue can be compared with images received by video endoscopy using a white light source. The set- up is required to produce a better contrast between infected and healthy tissue and might serve as a constructive diagnostic help for surgeons. The fundamental idea is to scan a low-power laser beam on an imaging fiber bundle and to achieve a spatially resolved projection on the tissue surface. A sufficiently high laser intensity from the diode laser is concentrated on each single spot of the tissue exciting fluorescence when a dye has previously been accumulated. Subsequently, video image of the tissue is recorded and stored. With an image processing unit, video and fluorescence images are overlaid producing a picture of the fluorescence intensity in the environment of the observed tissue.

  3. Spectrally enhanced imaging of occlusal surfaces and artificial shallow enamel erosions with a scanning fiber endoscope

    Science.gov (United States)

    Zhang, Liang; Nelson, Leonard Y.; Seibel, Eric J.

    2012-07-01

    An ultrathin scanning fiber endoscope, originally developed for cancer diagnosis, was used to image dental occlusal surfaces as well as shallow artificially induced enamel erosions from human extracted teeth (n=40). Enhanced image resolution of occlusal surfaces was obtained using a short-wavelength 405-nm illumination laser. In addition, artificial erosions of varying depths were also imaged with 405-, 404-, 532-, and 635-nm illumination lasers. Laser-induced autofluorescence images of the teeth using 405-nm illumination were also obtained. Contrast between sound and eroded enamel was quantitatively computed for each imaging modality. For shallow erosions, the image contrast with respect to sound enamel was greatest for the 405-nm reflected image. It was also determined that the increased contrast was in large part due to volume scattering with a smaller component from surface scattering. Furthermore, images obtained with a shallow penetration depth illumination laser (405 nm) provided the greatest detail of surface enamel topography since the reflected light does not contain contributions from light reflected from greater depths within the enamel tissue. Multilayered Monte Carlo simulations were also performed to confirm the experimental results.

  4. Toward endoscopes with no distal optics: video-rate scanning microscopy through a fiber bundle.

    Science.gov (United States)

    Andresen, Esben Ravn; Bouwmans, Géraud; Monneret, Serge; Rigneault, Hervé

    2013-03-01

    We report a step toward scanning endomicroscopy without distal optics. The focusing of the beam at the distal end of a fiber bundle is achieved by imposing a parabolic phase profile across the exit face with the aid of a spatial light modulator. We achieve video-rate images by galvanometric scanning of the phase tilt at the proximal end. The approach is made possible by the bundle, designed to have very low coupling between cores.

  5. A 3D scanning laser endoscope architecture utilizing a circular piezoelectric membrane

    Science.gov (United States)

    Khayatzadeh, Ramin; Çivitci, Fehmi; Ferhanoğlu, Onur

    2017-12-01

    A piezo-scanning fiber endoscopic device architecture is proposed for 3D imaging or ablation. The endoscopic device consists of a piezoelectric membrane that is placed perpendicular to the optical axis, a fiber optic cable that extends out from and actuated by the piezoelectric membrane, and one or multiple lenses for beam delivery and collection. Unlike its counterparts that utilize piezoelectric cylinders for fiber actuation, the proposed architecture offers quasi-static actuation in the axial direction along with resonant actuation in the lateral directions forming a 3D scanning pattern, allowing adjustment of the focus plane. The actuation of the four-quadrant piezoelectric membrane involves driving of two orthogonal electrodes with AC signals for lateral scanning, while simultaneously driving all electrodes for axial scanning and focus adjustment. We have characterized piezoelectric membranes (5 -15mm diameter) with varying sizes to monitor axial displacement behavior with respect to applied DC voltage. We also demonstrate simultaneous lateral and axial actuation on a resolution target, and observe the change of lateral resolution on a selected plane through performing 1D cross-sectional images, as an indicator of focal shift through axial actuation. Based on experimental results, we identify the optical and geometrical parameters for optimal 3D imaging of tissue samples. Our findings reveal that a simple piezoelectric membrane, having comparable dimensions and drive voltage requirement with off-the-shelf MEMS scanner chips, offers tissue epithelial imaging with sub-cellular resolution.

  6. Targeted detection of murine colonic dysplasia in vivo with flexible multispectral scanning fiber endoscopy

    Science.gov (United States)

    Joshi, Bishnu P.; Miller, Sharon J.; Lee, Cameron; Gustad, Adam; Seibel, Eric J.; Wang, Thomas D.

    2012-02-01

    We demonstrate a multi-spectral scanning fiber endoscope (SFE) that collects fluorescence images in vivo from three target peptides that bind specifically to murine colonic adenomas. This ultrathin endoscope was demonstrated in a genetically engineered mouse model of spontaneous colorectal adenomas based on somatic Apc (adenomatous polyposis coli) gene inactivation. The SFE delivers excitation at 440, 532, 635 nm with human patients by simultaneously visualizing multiple over expressed molecular targets unique to dysplasia.

  7. Fiber coupled ultrafast scanning tunneling microscope

    DEFF Research Database (Denmark)

    Keil, Ulrich Dieter Felix; Jensen, Jacob Riis; Hvam, Jørn Märcher

    1997-01-01

    We report on a scanning tunneling microscope with a photoconductive gate in the tunneling current circuit. The tunneling tip is attached to a coplanar transmission line with an integrated photoconductive switch. The switch is illuminated through a fiber which is rigidly attached to the switch...... waveguide. The measurements show that the probe works as a transient voltage detector in contact and a capacitively coupled transient field detector in tunneling mode. We do not measure the transient voltage change in the ohmic tunneling current. In this sense, the spatial resolution for propagating...... substrate. By using a firmly attached fiber we achieve an excellent reproducibility and unconstrained positioning of the tip. We observe a transient signal with 2.9 ps pulse width in tunneling mode and 5 ps in contact mode. The instrument is applied to investigating the mode structure on a coplanar...

  8. Ultrathin endoscopes based on multicore fibers and adaptive optics: a status review and perspectives.

    Science.gov (United States)

    Andresen, Esben Ravn; Sivankutty, Siddharth; Tsvirkun, Viktor; Bouwmans, Géraud; Rigneault, Hervé

    2016-12-01

    We take stock of the progress that has been made into developing ultrathin endoscopes assisted by wave front shaping. We focus our review on multicore fiber-based lensless endoscopes intended for multiphoton imaging applications. We put the work into perspective by comparing with alternative approaches and by outlining the challenges that lie ahead.

  9. MEMS-based non-rotatory circumferential scanning optical probe for endoscopic optical coherence tomography

    Science.gov (United States)

    Xu, Yingshun; Singh, Janak; Siang, Teo Hui; Ramakrishna, Kotlanka; Premchandran, C. S.; Sheng, Chen Wei; Kuan, Chuah Tong; Chen, Nanguang; Olivo, Malini C.; Sheppard, Colin J. R.

    2007-07-01

    In this paper, we present a non-rotatory circumferential scanning optical probe integrated with a MEMS scanner for in vivo endoscopic optical coherence tomography (OCT). OCT is an emerging optical imaging technique that allows high resolution cross-sectional imaging of tissue microstructure. To extend its usage to endoscopic applications, a miniaturized optical probe based on Microelectromechanical Systems (MEMS) fabrication techniques is currently desired. A 3D electrothermally actuated micromirror realized using micromachining single crystal silicon (SCS) process highlights its very large angular deflection, about 45 degree, with low driving voltage for safety consideration. The micromirror is integrated with a GRIN lens into a waterproof package which is compatible with requirements for minimally invasive endoscopic procedures. To implement circumferential scanning substantially for diagnosis on certain pathological conditions, such as Barret's esophagus, the micromirror is mounted on 90 degree to optical axis of GRIN lens. 4 Bimorph actuators that are connected to the mirror on one end via supporting beams and springs are selected in this micromirror design. When actuators of the micromirror are driven by 4 channels of sinusoidal waveforms with 90 degree phase differences, beam focused by a GRIN is redirected out of the endoscope by 45 degree tilting mirror plate and achieve circumferential scanning pattern. This novel driving method making full use of very large angular deflection capability of our micromirror is totally different from previously developed or developing micromotor-like rotatory MEMS device for circumferential scanning.

  10. Interferometric microstructured polymer optical fiber ultrasound sensor for optoacoustic endoscopic imaging in biomedical applications

    DEFF Research Database (Denmark)

    Gallego, Daniel; Sáez-Rodríguez, David; Webb, David

    2014-01-01

    to conventional piezoelectric transducers. These kind of sensors, made of biocompatible polymers, are good candidates for the sensing element in an optoacoustic endoscope because of its high sensitivity, its shape and its non-brittle and non-electric nature. The acoustic sensitivity of the intrinsic fiber optic......We report a characterization of the acoustic sensitivity of microstructured polymer optical fiber interferometric sensors at ultrasonic frequencies from 100kHz to 10MHz. The use of wide-band ultrasonic fiber optic sensors in biomedical ultrasonic and optoacoustic applications is an open alternative...... interferometric sensors depends strongly of the material which is composed of. In this work we compare experimentally the intrinsic ultrasonic sensitivities of a PMMA mPOF with other three optical fibers: a singlemode silica optical fiber, a single-mode polymer optical fiber and a multimode graded...

  11. Demonstration of full 4×4 Mueller polarimetry through an optical fiber for endoscopic applications.

    Science.gov (United States)

    Manhas, Sandeep; Vizet, Jérémy; Deby, Stanislas; Vanel, Jean-Charles; Boito, Paola; Verdier, Mireille; De Martino, Antonello; Pagnoux, Dominique

    2015-02-09

    A novel technique to measure the full 4 × 4 Mueller matrix of a sample through an optical fiber is proposed, opening the way for endoscopic applications of Mueller polarimetry for biomedical diagnosis. The technique is based on two subsequent Mueller matrices measurements: one for characterizing the fiber only, and another for the assembly of fiber and sample. From this differential measurement, we proved theoretically that the polarimetric properties of the sample can be deduced. The proof of principle was experimentally validated by measuring various polarimetric parameters of known optical components. Images of manufactured and biological samples acquired by using this approach are also presented.

  12. Eyewear-style three-dimensional endoscope derived from microstructured polymer fiber with the function of image transmission

    International Nuclear Information System (INIS)

    Kong De-Peng; Wang Li-Li; He Zheng-Quan; Ma Tian; Chu Jiu-Rong

    2013-01-01

    A method of fabricating multi-core polymer image fiber is proposed. Image fiber preform is fabricated by stacking thousands of polymer fibers each with a 0.25-mm diameter orderly in a die by only one step. The preform is heated and stretched into image fiber with an outer diameter of 2 mm. Then a portable eyewear-style three-dimensional (3D) endoscope system is designed, fabricated, and characterized. This endoscopic system is composed of two graded index lenses, two pieces of 0.35-m length image guide fibers, and a pair of oculars. It shows good flexibility and portability, and can provide the depth information accordingly. (general)

  13. Scanning fiber microdisplay: design, implementation, and comparison to MEMS mirror-based scanning displays.

    Science.gov (United States)

    Khayatzadeh, Ramin; Civitci, Fehmi; Ferhanoglu, Onur; Urey, Hakan

    2018-03-05

    In this study, we propose a compact, lightweight scanning fiber microdisplay towards virtual and augmented reality applications. Our design that is tailored as a head-worn-display simply consists of a four-quadrant piezoelectric tube actuator through which a fiber optics cable is extended and actuated, and a reflective (or semi-reflective) ellipsoidal surface that relays the moving tip of the fiber onto the viewer's retina. The proposed display, offers significant advantages in terms of architectural simplicity, form-factor, fabrication complexity and cost over other fiber scanner and MEMS mirror counterparts towards practical realization. We demonstrate the display of various patterns with ∼VGA resolution and further provide analytical formulas for mechanical and optical constraints to compare the performance of the proposed scanning fiber microdisplay with that of MEMS mirror-based microdisplays. Also we discuss the road steps towards improving the performance of the proposed scanning fiber microdisplay to high-definition video formats (such as HD1440), which is beyond what has been achieved by MEMS mirror based laser scanning displays.

  14. Optimizing pulse compressibility in completely all-fibered Ytterbium chirped pulse amplifiers for in vivo two photon laser scanning microscopy.

    Science.gov (United States)

    Fernández, A; Grüner-Nielsen, L; Andreana, M; Stadler, M; Kirchberger, S; Sturtzel, C; Distel, M; Zhu, L; Kautek, W; Leitgeb, R; Baltuska, A; Jespersen, K; Verhoef, A

    2017-08-01

    A simple and completely all-fiber Yb chirped pulse amplifier that uses a dispersion matched fiber stretcher and a spliced-on hollow core photonic bandgap fiber compressor is applied in nonlinear optical microscopy. This stretching-compression approach improves compressibility and helps to maximize the fluorescence signal in two-photon laser scanning microscopy as compared with approaches that use standard single mode fibers as stretcher. We also show that in femtosecond all-fiber systems, compensation of higher order dispersion terms is relevant even for pulses with relatively narrow bandwidths for applications relying on nonlinear optical effects. The completely all-fiber system was applied to image green fluorescent beads, a stained lily-of-the-valley root and rat-tail tendon. We also demonstrated in vivo imaging in zebrafish larvae, where we simultaneously measure second harmonic and fluorescence from two-photon excited red-fluorescent protein. Since the pulses are compressed in a fiber, this source is especially suited for upgrading existing laser scanning (confocal) microscopes with multiphoton imaging capabilities in space restricted settings or for incorporation in endoscope-based microscopy.

  15. Utility and safety of the flexible-fiber CO2 laser in endoscopic endonasal transsphenoidal surgery.

    Science.gov (United States)

    Jayarao, Mayur; Devaiah, Anand K; Chin, Lawrence S

    2011-01-01

    This study sought to report on the utility and safety of the flexible-fiber CO2 laser in endoscopic endonasal transsphenoidal surgery. A retrospective chart review identified 16 patients who underwent laser-assisted transsphenoidal surgery. All tumor pathology types were considered. Results were assessed based on hormone status, tumor size, pathology, complications, and resection rates. Sixteen pituitary lesions (pituitary adenomas, 12; Rathke cleft cyst, 2; pituitary cyst and craniopharyngioma, 1 each) with an average size of 22.7 mm were identified by radiographic and pathologic criteria. All patients underwent flexible-fiber CO2 laser-assisted endoscopic endonasal transsphenoidal surgery. Of the adenomas, 8 were nonsecreting and 4 were secreting (3 prolactinomas and 1 ACTH secreting). Gross total resection was achieved in 7 of 16 patients (43.75%) with hormone remission in all patients (100%) after a mean follow-up of 19.3 months. Postoperative complications occurred in 3 patients (18.75%): 2 patients developed transient diabetes insipidus (DI) and 1 developed a CSF leak requiring surgical repair. Five patients (31.25%) underwent postoperative radiation to the residual lesions. We found that CO2-laser-assisted endoscopic endonasal transsphenoidal surgery for sellar tumors is a minimally invasive approach using a tool that is quick and effective at cutting and coagulation. The surgery has a low rate of complication, and no laser-related complications were encountered. The laser fiber allows the surgeon to safely cut and coagulate without the line-of-sight problems encountered with conventional CO2 lasers. Further studies are recommended to further define its role in endoscopic endonasal sellar surgery. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Three dimensional phase imaging using a scanning optical fiber interferometer

    International Nuclear Information System (INIS)

    Walford, J.N.; Nugent, K.A.; Roberts, A.; Scholten, R.E.

    1998-01-01

    A quantitative method for measuring phase in three dimensions using a scanning optical fiber interferometer is described. By exploiting phase modulation in the reference arm, this technique is insensitive to large variations in the intensity of the field being studied, and is therefore highly suitable for measurement of phase within spatially confined optical beams. It uses only a single detector, and is not reliant on lock-in electronics. The technique is applied to the measurement of the near field of a cleaved optical fiber and shown to produce results in good agreement with theory. (authors)

  17. Excitation-scanning hyperspectral imaging system for microscopic and endoscopic applications

    Science.gov (United States)

    Mayes, Sam A.; Leavesley, Silas J.; Rich, Thomas C.

    2016-04-01

    Current microscopic and endoscopic technologies for cancer screening utilize white-light illumination sources. Hyper-spectral imaging has been shown to improve sensitivity while retaining specificity when compared to white-light imaging in both microscopy and in vivo imaging. However, hyperspectral imaging methods have historically suffered from slow acquisition times due to the narrow bandwidth of spectral filters. Often minutes are required to gather a full image stack. We have developed a novel approach called excitation-scanning hyperspectral imaging that provides 2-3 orders of magnitude increased signal strength. This reduces acquisition times significantly, allowing for live video acquisition. Here, we describe a preliminary prototype excitation-scanning hyperspectral imaging system that can be coupled with endoscopes or microscopes for hyperspectral imaging of tissues and cells. Our system is comprised of three subsystems: illumination, transmission, and imaging. The illumination subsystem employs light-emitting diode arrays to illuminate at different wavelengths. The transmission subsystem utilizes a unique geometry of optics and a liquid light guide. Software controls allow us to interface with and control the subsystems and components. Digital and analog signals are used to coordinate wavelength intensity, cycling and camera triggering. Testing of the system shows it can cycle 16 wavelengths at as fast as 1 ms per cycle. Additionally, more than 18% of the light transmits through the system. Our setup should allow for hyperspectral imaging of tissue and cells in real time.

  18. Endoscopic ultrasonography and computed tomography scanning for preoperative staging of colonic cancer

    DEFF Research Database (Denmark)

    Malmstrøm, M L; Gögenur, I; Riis, L B

    2017-01-01

    PURPOSE: With an increasing demand for more accurate preoperative staging methods for colon cancer, we aimed to compare preoperative tumour (T)- and nodal (N)-stage in patients with left-sided colon cancer by endoscopic ultrasonography (EUS) and computed tomography (CT) with post......-operative histology as gold standard. METHODS: A total of 44 patients were prospectively recruited at Herlev and Roskilde University Hospitals during November 2014-January 2016. Thirty-five patients were included in the final analysis and underwent EUS, CT and surgery within 2 weeks. Diagnostic values were evaluated...... difficult to evaluate due to small patient numbers. EUS could be considered as a supplement to CT scans in selecting patients for neoadjuvant therapies, or local transmural treatment, in the future. TRIAL REGISTRATION: NCT02324023....

  19. Focus scanning with feedback control for fiber-optic nonlinear endomicroscopy (Conference Presentation)

    Science.gov (United States)

    Li, Ang; Liang, Wenxuan; Li, Xingde

    2017-02-01

    Fiber-optic nonlinear endomicroscopy represents a strong promise to enable translation of nonlinear microscopy technologies to in vivo applications, particularly imaging of internal organs. Two-dimensional imaging beam scanning has been accomplished by using fiber-optic scanners or MEMS scanners. Yet nonlinear endomicroscopy still cannot perform rapid and reliable depth or focus scanning while maintaining a small form factor. Shape memory alloy (SMA) wire had shown promise in extending 2D endoscopic imaging to the third dimension. By Joule heating, the SMA wire would contract and move the endomicroscope optics to change beam focus. However, this method suffered from hysteresis, and was susceptible to change in ambient temperature, making it difficult to achieve accurate and reliable depth scanning. Here we present a feedback-controlled SMA actuator which addressed these challenges. The core of the feedback loop was a Hall effect sensor. By measuring the magnetic flux density from a tiny magnet attached to the SMA wire, contraction distance of the SMA wire could be tracked in real time. The distance was then fed to the PID algorithm running in a microprocessor, which computed the error between the command position and the current position of the actuator. The current running through the SMA wire was adjusted accordingly. Our feedback-controlled SMA actuator had a tube-like shape with outer diameter of 5.5 mm and length of 25 mm, and was designed to house the endomicroscope inside. Initial test showed that it allowed more than 300 microns of travel distance, with an average positioning error of less than 2 microns. 3D imaging experiments with the endomicroscope is underway, and its imaging performance will be assessed and discussed.

  20. Novel Technique for Quantitative Fast Scanning Calorimetry on Electrospun Fibers

    Science.gov (United States)

    Thomas, David; Govinna, Nelaka; Schick, Christoph; Cebe, Peggy

    Fast scanning chip calorimetry allows for the study of polymers which have rapid nucleation and/or crystallization kinetics, or degrade within their melting range. Heating rates used, up to 4000 K/s, allow studies of hetero and homogeneous nucleation at time scales inaccessible with conventional calorimeters, whose rates are typically alcohol (PVA) were chosen in the development of a new methodology to obtain quantitative fast scanning thermal data from electrospun nanofibers using a Flash DSC1. The structure of nanofibers requires special methods to load nanogram-sized samples onto a UFSC1 sensor. Fibers were directly spun onto TEM grids which provide a durable substrate to support bundles of nanofibers and possess excellent thermal conductivity allowing for a strong, repeatable signal and ensure good sample to sensor contact. As spun samples were held isothermally at temperatures ranging from Tg to Tm then heated at 2,000 K/s to assess as-spun crystallinity and cold crystallization behaviors. Above Tm the fibers break up into micro- and nano-droplets. On these samples, melt crystallization experiments were performed to study nucleation and crystallization of polymer confined to nanodroplet morphology. NSF DMR-1608125.

  1. Quantitative evaluation of catheter radiopacity by fiber optic scanning densitometry

    International Nuclear Information System (INIS)

    Solomon, D.D.; Byron, M.P.; Lipton, M.J.

    1989-01-01

    A rapid accurate method has been developed utilizing fiber optic scanning densitometry to quantify the radiopacity of vascular catheters. The technique provides for computerized calculation of relative catheter radiopacity and an appropriate control standard. A densitometer with a 180 degree collection angle for diffuse transmission density measurements was selected based on the diffusing nature of X-ray film (Q-factor 1.80). A benchmark catheter and 2 mil thick brass shim stock were selected as control standards for evaluation of mono-and multilumen tubing using standard X-ray conditions and an aluminum block attenuator. The authors present results from reproducibility studies which show scan-to-scan repeatability is within ±1%, and day-to-day variability is less than 5%. Application studies demonstrate a linear relationship between percent barium sulfate loading and the radiopaqueness of 16 gauge monolumen tubing. Results were also obtained from a clinical chest X-ray film showing good in-vivo/in-vitro correlation

  2. Retinal nerve fiber layer assessment by scanning laser polarimetry and standardized photography

    NARCIS (Netherlands)

    Niessen, A. G.; van den Berg, T. J.; Langerhorst, C. T.; Greve, E. L.

    1996-01-01

    To determine whether, in a clinical setting, scanning laser polarimetry and retinal nerve fiber layer photography provide equivalent information on the retinal nerve fiber layer. We prospectively studied 60 patients with glaucoma or ocular hypertension and 24 healthy subjects. With scanning laser

  3. Fabrication of Shatter-Proof Metal Hollow-Core Optical Fibers for Endoscopic Mid-Infrared Laser Applications

    Directory of Open Access Journals (Sweden)

    Katsumasa Iwai

    2018-04-01

    Full Text Available A method for fabricating robust and thin hollow-core optical fibers that carry mid-infrared light is proposed for use in endoscopic laser applications. The fiber is made of stainless steel tubing, eliminating the risk of scattering small glass fragments inside the body if the fiber breaks. To reduce the inner surface roughness of the tubing, a polymer base layer is formed prior to depositing silver and optical-polymer layers that confine light inside the hollow core. The surface roughness is greatly decreased by re-coating thin polymer base layers. Because of this smooth base layer surface, a uniform optical-polymer film can be formed around the core. As a result, clear interference peaks are observed in both the visible and mid-infrared regions. Transmission losses were also low for the carbon dioxide laser used for medical treatments as well as the visible laser diode used for an aiming beam. Measurements of bending losses for these lasers demonstrate the feasibility of the designed fiber for endoscopic applications.

  4. Optical fiber-based full Mueller polarimeter for endoscopic imaging using a two-wavelength simultaneous measurement method.

    Science.gov (United States)

    Vizet, Jérémy; Manhas, Sandeep; Tran, Jacqueline; Validire, Pierre; Benali, Abdelali; Garcia-Caurel, Enric; Pierangelo, Angelo; De Martino, Antonello; Pagnoux, Dominique

    2016-07-01

    This paper reports a technique based on spectrally differential measurement for determining the full Mueller matrix of a biological sample through an optical fiber. In this technique, two close wavelengths were used simultaneously, one for characterizing the fiber and the other for characterizing the assembly of fiber and sample. The characteristics of the fiber measured at one wavelength were used to decouple its contribution from the measurement on the assembly of fiber and sample and then to extract sample Mueller matrix at the second wavelength. The proof of concept was experimentally validated by measuring polarimetric parameters of various calibrated optical components through the optical fiber. Then, polarimetric images of histological cuts of human colon tissues were measured, and retardance, diattenuation, and orientation of the main axes of fibrillar regions were displayed. Finally, these images were successfully compared with images obtained by a free space Mueller microscope. As the reported method does not use any moving component, it offers attractive integration possibilities with an endoscopic probe.

  5. Characterization of metal-coated fiber tip for NSOM lithography by tip-to-tip scan

    International Nuclear Information System (INIS)

    Kubicova, I.; Pudis, D.; Suslik, L.; Skriniarova, J.

    2011-01-01

    For the optical field characterization, a tip-to-tip scan of two metal-coated fiber tips with circular aperture at the apex was performed. The optical field irradiated from the fiber probe in illumination mode was analyzed by NSOM represented by fiber probe in collection mode. The near-field intensity profile of the source fiber tip in the plane perpendicular to the axis of the tip was taken. Experimental stage requires high resolution 3D motion system controlled by computer (Fig. 1). The source and the detector fiber tip were placed on the moving and static part of the 3D nanoposition system, respectively. As a light source, a modulated 473 nm DPSS laser was used. After the source fiber tip characterization, the NSOM lithography was performed. In the experimental setup from Fig. 1, the detector fiber tip was replaced by a sample fixed in a vacuum holder. As a sample, a 600 nm positive photoresist AZ 5214E was spin-coated on a GaAs substrate. Exposure was carried out by irradiation of the sample at desired positions through the fiber tip aperture. The sample was developed in AZ 400K developer for 30 s and rinsed in DI water. A promising tip-to-tip scanning technique for characterization of metal-coated fiber tips with aperture at the apex was presented. Nearly-circular aperture shapes were documented from NSOM measurements with diameter estimated to be less than 460 nm. By knowing the source-detector distance and the FWHM of the near-field intensity profile, the tip-to-tip scan proves an easy and fast method to analyze the fiber tip aperture properties. The fiber tip resolution was confirmed by preparation of 2D planar structures in thin photoresist layer, where the NSOM lithography uses the metal-coated fiber tip characterized in previous section. (authors)

  6. Near-field scanning optical microscopy using polymethylmethacrylate optical fiber probes

    International Nuclear Information System (INIS)

    Chibani, H.; Dukenbayev, K.; Mensi, M.; Sekatskii, S.K.; Dietler, G.

    2010-01-01

    We report the first use of polymethylmethacrylate (PMMA) optical fiber-made probes for scanning near-field optical microscopy (SNOM). The sharp tips were prepared by chemical etching of the fibers in ethyl acetate, and the probes were prepared by proper gluing of sharpened fibers onto the tuning fork in the conditions of the double resonance (working frequency of a tuning fork coincides with the resonance frequency of dithering of the free-standing part of the fiber) reported earlier for the case of glass fibers. Quality factors of the probes in the range 2000-6000 were obtained, which enables the realization of an excellent topographical resolution including state-of-art imaging of single DNA molecules. Near-field optical performance of the microscope is illustrated by the Photon Scanning Tunneling Microscope images of fluorescent beads with a diameter of 100 nm. The preparation of these plastic fiber probes proved to be easy, needs no hazardous material and/or procedures, and typical lifetime of a probe essentially exceeds that characteristic for the glass fiber probe.

  7. Carbon-fiber tips for scanning probe microscopes and molecular electronics experiments

    NARCIS (Netherlands)

    Rubio-Bollinger, G.; Castellanos-Gomez, A.; Bilan, S.; Zotti, L.A.; Arroyo, C.R.; Agraït, N.; Cuevas, J.

    2012-01-01

    We fabricate and characterize carbon-fiber tips for their use in combined scanning tunneling and force microscopy based on piezoelectric quartz tuning fork force sensors. An electrochemical fabrication procedure to etch the tips is used to yield reproducible sub-100-nm apex. We also study electron

  8. Retinal Nerve Fiber Layer Segmentation on FD-OCT Scans of Normal Subjects and Glaucoma Patients.

    Science.gov (United States)

    Mayer, Markus A; Hornegger, Joachim; Mardin, Christian Y; Tornow, Ralf P

    2010-11-08

    Automated measurements of the retinal nerve fiber layer thickness on circular OCT B-Scans provide physicians additional parameters for glaucoma diagnosis. We propose a novel retinal nerve fiber layer segmentation algorithm for frequency domain data that can be applied on scans from both normal healthy subjects, as well as glaucoma patients, using the same set of parameters. In addition, the algorithm remains almost unaffected by image quality. The main part of the segmentation process is based on the minimization of an energy function consisting of gradient and local smoothing terms. A quantitative evaluation comparing the automated segmentation results to manually corrected segmentations from three reviewers is performed. A total of 72 scans from glaucoma patients and 132 scans from normal subjects, all from different persons, composed the database for the evaluation of the segmentation algorithm. A mean absolute error per A-Scan of 2.9 µm was achieved on glaucomatous eyes, and 3.6 µm on healthy eyes. The mean absolute segmentation error over all A-Scans lies below 10 µm on 95.1% of the images. Thus our approach provides a reliable tool for extracting diagnostic relevant parameters from OCT B-Scans for glaucoma diagnosis.

  9. Optical coherence tomography, scanning laser polarimetry and confocal scanning laser ophthalmoscopy in retinal nerve fiber layer measurements of glaucoma patients.

    Science.gov (United States)

    Fanihagh, Farsad; Kremmer, Stephan; Anastassiou, Gerasimos; Schallenberg, Maurice

    2015-01-01

    To determine the correlations and strength of association between different imaging systems in analyzing the retinal nerve fiber layer (RNFL) of glaucoma patients: optical coherence tomography (OCT), scanning laser polarimetry (SLP) and confocal scanning laser ophthalmoscopy (CSLO). 114 eyes of patients with moderate open angle glaucoma underwent spectral domain OCT (Topcon SD-OCT 2000 and Zeiss Cirrus HD-OCT), SLP (GDx VCC and GDx Pro) and CSLO (Heidelberg Retina Tomograph, HRT 3). Correlation coefficients were calculated between the structural parameters yielded by these examinations. The quantitative relationship between the measured RNFL thickness globally and for the four regions (superior, inferior, nasal, temporal) were evaluated with different regression models for all used imaging systems. The strongest correlation of RNFL measurements was found between devices using the same technology like GDx VCC and GDx Pro as well as Topcon OCT and Cirrus OCT. In glaucoma patients, the strongest associations (R²) were found between RNFL measurements of the two optical coherence tomography devices Topcon OCT and Cirrus OCT (R² = 0.513) and between GDx VCC and GDx Pro (R² = 0.451). The results of the OCTs and GDX Pro also had a strong quantitative relationship (Topcon OCT R² = 0.339 and Cirrus OCT R² = 0.347). GDx VCC and the OCTs showed a mild to moderate association (Topcon OCT R² = 0.207 and Cirrus OCT R² = 0.258). The confocal scanning laser ophthalmoscopy (HRT 3) had the lowest association to all other devices (Topcon OCT R² = 0.254, Cirrus OCT R² = 0.158, GDx Pro R² = 0.086 and GDx VCC R² = 0.1). The measurements of the RNFL in glaucoma patients reveal a high correlation of OCT and GDx devices because OCTs can measure all major retinal layers and SLP can detect nerve fibers allowing a comparison between the results of this devices. However, CSLO by means of HRT topography can only measure height values of the retinal surface but it cannot distinguish

  10. Heat accumulation between scans during multi-pass cutting of carbon fiber reinforced plastics

    Science.gov (United States)

    Kononenko, T. V.; Freitag, C.; Komlenok, M. S.; Weber, R.; Graf, T.; Konov, V. I.

    2018-02-01

    Matrix evaporation caused by heat accumulation between scans (HAS) was studied in the case of multi-pass scanning of a laser beam over the surface of carbon fiber reinforced plastic (CFRP). The experiments were performed in two regimes, namely, in the process of CFRP cutting and in the regime of low-fluence irradiation avoiding ablation of carbon fibers. The feature of the ablation-free regime is that all absorbed energy remains in the material as heat, while in the cutting regime the fraction of residual heat is unknown. An analytical model based on two-dimensional (2D) heat flow was applied to predict the critical number of scans, after which the HAS effect causes a distinct growth of the matrix evaporation zone (MEZ). According to the model, the critical number of scans decreases exponentially with increasing laser power, while no dependence on the feed rate is expected. It was found that the model fits well to the experimental data obtained in the ablation-free regime where the heat input is well defined and known. In the cutting regime the measured significant reduction of the critical number of scans observed in deep grooves may be attributed to transformation of the heat flow geometry and to an expected increase of the residual heat fraction.

  11. Industrial site particulate pollution monitoring with an eye-safe and scanning industrial fiber lidar

    Science.gov (United States)

    Belanger, Brigitte; Fougeres, Andre; Talbot, Mario

    2001-02-01

    12 Over the past few years, INO has developed an Industrial Fiber Lidar (IFL). It enables the particulate pollution monitoring on industrial sites. More particularly, it has been used to take measurements of particulate concentration at Port Facilities of an aluminum plant during boat unloading. It is an eye-safe and portable lidar. It uses a fiber laser also developed at INO emitting 1.7 microJoules at 1534 nm with a pulse repetition frequency of 5 kHz. Given the harsh environment of an industrial site, all the sensitive equipment like the laser source, detector, computer and acquisition electronics are located in a building and connected to the optical module, placed outside, via optical fibers up to 500 m long. The fiber link also offers all the flexibility for placing the optical module at a proper location. The optical module is mounted on a two axis scanning platform, able to perform an azimuth scan of 0 to 355 deg and an elevation scan of +/- 90 deg, which enables the scanning of zones defined by the user. On this industrial site, materials like bauxite, alumina, spathfluor and calcined coke having mass extinction coefficients ranging from 0.53 to 2.7 m2/g can be detected. Data for different measurement configurations have been obtained. Concentration values have been calculated for measurements in a hopper, along a wharf and over the urban area close to the port facilities. The lidar measurements have been compared to high volume samplers. Based on these comparisons, it has been established that the IFL is able to monitor the relative fluctuations of dust concentrations. It can be integrated to the process control of the industrial site for alarm generation when concentrations are above threshold.

  12. True Tapping Mode Scanning Near-Field Optical Microscopy with Bent Glass Fiber Probes.

    Science.gov (United States)

    Smirnov, A; Yasinskii, V M; Filimonenko, D S; Rostova, E; Dietler, G; Sekatskii, S K

    2018-01-01

    In scanning near-field optical microscopy, the most popular probes are made of sharpened glass fiber attached to a quartz tuning fork (TF) and exploiting the shear force-based feedback. The use of tapping mode feedback could be preferable. Such an approach can be realized, for example, using bent fiber probes. Detailed analysis of fiber vibration modes shows that realization of truly tapping mode of the probe dithering requires an extreme caution. In case of using the second resonance mode, probes vibrate mostly in shear force mode unless the bending radius is rather small (ca. 0.3 mm) and the probe's tip is short. Otherwise, the shear force character of the dithering persists. Probes having these characteristics were prepared by irradiation of a tapered etched glass fiber with a CW CO 2 laser. These probes were attached to the TF in double resonance conditions which enables achieving significant quality factor (4000-6000) of the TF + probe system (Cherkun et al., 2006). We also show that, to achieve a truly tapping character, dithering, short, and not exceeding 3 mm lengths of a freestanding part of bent fiber probe beam should also be used in the case of nonresonant excitation.

  13. True Tapping Mode Scanning Near-Field Optical Microscopy with Bent Glass Fiber Probes

    Directory of Open Access Journals (Sweden)

    A. Smirnov

    2018-01-01

    Full Text Available In scanning near-field optical microscopy, the most popular probes are made of sharpened glass fiber attached to a quartz tuning fork (TF and exploiting the shear force-based feedback. The use of tapping mode feedback could be preferable. Such an approach can be realized, for example, using bent fiber probes. Detailed analysis of fiber vibration modes shows that realization of truly tapping mode of the probe dithering requires an extreme caution. In case of using the second resonance mode, probes vibrate mostly in shear force mode unless the bending radius is rather small (ca. 0.3 mm and the probe’s tip is short. Otherwise, the shear force character of the dithering persists. Probes having these characteristics were prepared by irradiation of a tapered etched glass fiber with a CW CO2 laser. These probes were attached to the TF in double resonance conditions which enables achieving significant quality factor (4000–6000 of the TF + probe system (Cherkun et al., 2006. We also show that, to achieve a truly tapping character, dithering, short, and not exceeding 3 mm lengths of a freestanding part of bent fiber probe beam should also be used in the case of nonresonant excitation.

  14. Composite cavity based fiber optic Fabry–Perot strain sensors demodulated by an unbalanced fiber optic Michelson interferometer with an electrical scanning mirror

    International Nuclear Information System (INIS)

    Zhang, Jianzhong; Yang, Jun; Sun, Weimin; Yuan, Libo; Jin, Wencai; Peng, G D

    2008-01-01

    A composite cavity based fiber optic Fabry–Perot strain sensor system, interrogated by a white light source and demodulated by an unbalanced fiber optic Michelson interferometer with an electrical scanning mirror, is proposed and demonstrated. Comparing with the traditional extrinsic fiber optic Fabry–Perot strain sensor, the potential multiplexing capability and the dynamic measurement range are improved simultaneously. At the same time, the measurement stability of the electrical scanning mirror system is improved by the self-referenced signal of the sensor structure

  15. Fabrication and characterization of optical-fiber nanoprobes for scanning near-field optical microscopy.

    Science.gov (United States)

    Essaidi, N; Chen, Y; Kottler, V; Cambril, E; Mayeux, C; Ronarch, N; Vieu, C

    1998-02-01

    The current scanning near-field optical microscopy has been developed with optical-fiber probes obtained by use of either laser-heated pulling or chemical etching. For high-resolution near-field imaging, the detected signal is rapidly attenuated as the aperture size of the probe decreases. It is thus important to fabricate probes optimized for both spot size and optical transmission. We present a two-step fabrication that allowed us to achieve an improved performance of the optical-fiber probes. Initially, a CO(2) laser-heated pulling was used to produce a parabolic transitional taper ending with a top thin filament. Then, a rapid chemical etching with 50% buffered hydrofluoric acid was used to remove the thin filament and to result in a final conical tip on the top of the parabolic transitional taper. Systematically, we obtained optical-fiber nanoprobes with the apex size as small as 10 nm and the final cone angle varying from 15 degrees to 80 degrees . It was found that the optical transmission efficiency increases rapidly as the taper angle increases from 15 degrees to 50 degrees , but a further increase in the taper angle gives rise to important broadening of the spot size. Finally, the fabricated nanoprobes were used in photon-scanning tunneling microscopy, which allowed observation of etched double lines and grating structures with periods as small as 200 nm.

  16. Scanning laser polarimetry retinal nerve fiber layer thickness measurements after LASIK.

    Science.gov (United States)

    Zangwill, Linda M; Abunto, Teresa; Bowd, Christopher; Angeles, Raymund; Schanzlin, David J; Weinreb, Robert N

    2005-02-01

    To compare retinal nerve fiber layer (RNFL) thickness measurements before and after LASIK. Cohort study. Twenty participants undergoing LASIK and 14 normal controls. Retinal nerve fiber layer thickness was measured before LASIK and approximately 3 months after surgery in one eye each of 20 patients using a scanning laser polarimeter (GDx Nerve Fiber Analyzer) with fixed corneal compensation (FCC), one with variable corneal compensation (GDx VCC), and optical coherence tomography (OCT). Fourteen normal controls also were tested at baseline and approximately 3 months later. Retinal nerve fiber layer thicknesses measured with the GDx FCC, GDx VCC, and OCT. At baseline, mean (95% confidence interval [CI]) RNFL thicknesses for the GDx FCC, GDx VCC, and OCT were 78.1 microm (72.2-83.9), 54.3 microm (52.7-56.0), and 96.8 microm (93.2-100.5), respectively. In both LASIK and control groups, there were no significant changes between baseline and follow-up examinations in GDx VCC and OCT RNFL thickness measurements globally or in the superior and inferior quadrants (mean change, FCC measurements between baseline and follow-up. In LASIK patients, significant reductions were observed in GDx FCC RNFL measurements. Average absolute values of the mean (95% CI) change in thickness were 12.4 microm (7.7-17.2), 15.3 microm (9.6-20.9), and 12.9 microm (7.6-18.1) for GDx FCC RNFL measurements superiorly, inferiorly, and globally, respectively (all Ps FCC RNFL thickness measurements after LASIK is a measurement artifact and is most likely due to erroneous compensation for corneal birefringence. With scanning laser polarimetry, it is mandatory to compensate individually for change in corneal birefringence after LASIK to ensure accurate RNFL assessment.

  17. Retinal nerve fiber layer measurements by scanning laser polarimetry with enhanced corneal compensation in healthy subjects.

    Science.gov (United States)

    Rao, Harsha L; Venkatesh, Chirravuri R; Vidyasagar, Kelli; Yadav, Ravi K; Addepalli, Uday K; Jude, Aarthi; Senthil, Sirisha; Garudadri, Chandra S

    2014-12-01

    To evaluate the (i) effects of biological (age and axial length) and instrument-related [typical scan score (TSS) and corneal birefringence] parameters on the retinal nerve fiber layer (RNFL) measurements and (ii) repeatability of RNFL measurements with the enhanced corneal compensation (ECC) protocol of scanning laser polarimetry (SLP) in healthy subjects. In a cross-sectional study, 140 eyes of 73 healthy subjects underwent RNFL imaging with the ECC protocol of SLP. Linear mixed modeling methods were used to evaluate the effects of age, axial length, TSS, and corneal birefringence on RNFL measurements. One randomly selected eye of 48 subjects from the cohort underwent 3 serial scans during the same session to determine the repeatability. Age significantly influenced all RNFL measurements. RNFL measurements decreased by 1 µm for every decade increase in age. TSS affected the overall average RNFL measurement (β=-0.62, P=0.003), whereas residual anterior segment retardance affected the superior quadrant measurement (β=1.14, P=0.01). Axial length and corneal birefringence measurements did not influence RNFL measurements. Repeatability, as assessed by the coefficient of variation, ranged between 1.7% for the overall average RNFL measurement and 11.4% for th nerve fiber indicator. Age significantly affected all RNFL measurements with the ECC protocol of SLP, whereas TSS and residual anterior segment retardance affected the overall average and the superior average RNFL measurements, respectively. Axial length and corneal birefringence measurements did not influence any RNFL measurements. RNFL measurements had good intrasession repeatability. These results are important while evaluating the change in structural measurements over time in glaucoma patients.

  18. High-resolution imaging of retinal nerve fiber bundles in glaucoma using adaptive optics scanning laser ophthalmoscopy.

    Science.gov (United States)

    Takayama, Kohei; Ooto, Sotaro; Hangai, Masanori; Ueda-Arakawa, Naoko; Yoshida, Sachiko; Akagi, Tadamichi; Ikeda, Hanako Ohashi; Nonaka, Atsushi; Hanebuchi, Masaaki; Inoue, Takashi; Yoshimura, Nagahisa

    2013-05-01

    To detect pathologic changes in retinal nerve fiber bundles in glaucomatous eyes seen on images obtained by adaptive optics (AO) scanning laser ophthalmoscopy (AO SLO). Prospective cross-sectional study. Twenty-eight eyes of 28 patients with open-angle glaucoma and 21 normal eyes of 21 volunteer subjects underwent a full ophthalmologic examination, visual field testing using a Humphrey Field Analyzer, fundus photography, red-free SLO imaging, spectral-domain optical coherence tomography, and imaging with an original prototype AO SLO system. The AO SLO images showed many hyperreflective bundles suggesting nerve fiber bundles. In glaucomatous eyes, the nerve fiber bundles were narrower than in normal eyes, and the nerve fiber layer thickness was correlated with the nerve fiber bundle widths on AO SLO (P fiber layer defect area on fundus photography, the nerve fiber bundles on AO SLO were narrower compared with those in normal eyes (P optic disc, the nerve fiber bundle width was significantly lower, even in areas without nerve fiber layer defect, in eyes with glaucomatous eyes compared with normal eyes (P = .026). The mean deviations of each cluster in visual field testing were correlated with the corresponding nerve fiber bundle widths (P = .017). AO SLO images showed reduced nerve fiber bundle widths both in clinically normal and abnormal areas of glaucomatous eyes, and these abnormalities were associated with visual field defects, suggesting that AO SLO may be useful for detecting early nerve fiber bundle abnormalities associated with loss of visual function. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. MICROSTRUCTURING OF SILICON SINGLE CRYSTALS BY FIBER LASER IN HIGH-SPEED SCANNING MODE

    Directory of Open Access Journals (Sweden)

    T. A. Trifonova

    2015-11-01

    Full Text Available Subject of Study. The surface structure of the silicon wafers (substrate with a thermally grown silicon dioxide on the surface (of SiO2/Si is studied after irradiation by pulse fiber laser of ILI-1-20 type. The main requirements for exposure modes of the system are: the preservation of the integrity of the film of silicon dioxide in the process of microstructuring and the absence of interference of surrounding irradiated areas of the substrate. Method. Studies were carried out on silicon wafers KEF-4,5 oriented in the crystallographic plane (111 with the source (natural silicon dioxide (SiO2 with thickness of about 4 nm, and SiO2 with 40 nm and 150 nm thickness, grown by thermal oxidation in moist oxygen. Also, wafers KHB-10 oriented in the plane (100 with 500 nm thickness of thermal oxide were investigated. Irradiation of SiO2/Si system was produced by laser complex based on ytterbium fiber pulse laser ILI-1-20. Nominal output power of the laser was 20 W, and the laser wavelength was λ = 1062 nm. Irradiation was carried out by a focused beam spot with a diameter of 25 microns and a pulse repetition rate of 99 kHz. The samples with 150 nm and 40 nm thickness of SiO2 were irradiated at a power density equal to 1,2·102 W/cm2, and the samples of SiO2 with 500 nm thickness were irradiated at a power density equal to 2,0·102 W/cm2. Scanning was performed using a two-axis Coordinate Scanning Device based on VM2500+ drives with control via a PC with the software package "SinMarkTM." Only one scan line was used at the maximum speed of the beam equal to 8750 mm/s. Morphology control of the irradiated samples was conducted by an optical microscope ZeissA1M with high-resolution CCD array. A scanning probe microscope Nanoedicator of the NT-MDT company was used for structural measurements. Main Results. It has been shown that at a single exposure of high-frequency pulsed laser radiation on SiO2/Si system, with maintaining the integrity of the SiO2 film

  20. The tensile testing of individual wood fibers using environmental scanning electron microscopy and video image analysis

    Science.gov (United States)

    Laurence Mott; Stephen M. Shaler; Leslie H. Groom; Bei-Hong Liang

    1995-01-01

    Relationships between virgin fiber types, fiber production techniques and mechanical properties are well understood and documented. For recycled fibers, however, these same relationships are confounded by unquantified degrees of further mechanical and chemical damage. To gain a more comprehensive understanding of the impact of recycling on secondary fibers, the...

  1. Application of carbon nanotubes to topographical resolution enhancement of tapered fiber scanning near field optical microscopy probes

    Science.gov (United States)

    Huntington, S. T.; Jarvis, S. P.

    2003-05-01

    Scanning near field optical microscopy (SNOM) probes are typically tapered optical fibers with metallic coatings. The tip diameters are generally in excess of 300 nm and thus provide poor topographical resolution. Here we report on the attachment multiwalled carbon nanotubes to the probes in order to substantially enhance the topographical resolution, without adversely affecting the optical resolution.

  2. Scanning Laser Polarimetry and Optical Coherence Tomography for Detection of Retinal Nerve Fiber Layer Defects

    Science.gov (United States)

    Oh, Jong-Hyun

    2009-01-01

    Purpose To compare the ability of scanning laser polarimetry with variable corneal compensation (GDx-VCC) and Stratus optical coherence tomography (OCT) to detect photographic retinal nerve fiber layer (RNFL) defects. Methods This retrospective cross-sectional study included 45 eyes of 45 consecutive glaucoma patients with RNFL defects in red-free fundus photographs. The superior and inferior temporal quadrants in each eye were included for data analysis separately. The location and presence of RNFL defects seen in red-free fundus photographs were compared with those seen in GDx-VCC deviation maps and OCT RNFL analysis maps for each quadrant. Results Of the 90 quadrants (45 eyes), 31 (34%) had no apparent RNFL defects, 29 (32%) had focal RNFL defects, and 30 (33%) had diffuse RNFL defects in red-free fundus photographs. The highest agreement between GDx-VCC and red-free photography was 73% when we defined GDx-VCC RNFL defects as a cluster of three or more color-coded squares (p<5%) along the traveling line of the retinal nerve fiber in the GDx-VCC deviation map (kappa value, 0.388; 95% confidence interval (CI), 0.195 to 0.582). The highest agreement between OCT and red-free photography was 85% (kappa value, 0.666; 95% CI, 0.506 to 0.825) when a value of 5% outside the normal limit for the OCT analysis map was used as a cut-off value for OCT RNFL defects. Conclusions According to the kappa values, the agreement between GDx-VCC deviation maps and red-free photography was poor, whereas the agreement between OCT analysis maps and red-free photography was good. PMID:19794943

  3. Development and Characterization of Carbon-Fiber Microbiosensors for Fast-Scan Cyclic Voltammetry

    Science.gov (United States)

    Lugo-Morales, Leyda Zoraida

    Electrochemistry has been shown to be a robust tool in neuroscience. The use of carbon-fiber microelectrodes coupled with background-subtracted fast-scan cyclic voltammetry (FSCV) offers high sensitivity, selectivity, as well as the spatial and temporal resolution necessary for monitoring rapid fluctuations of electroactive molecules in live brain tissue. Dopamine (DA) is a neurotransmitter playing a key role in the regulation of reward and motivated behavior. FSCV has been used to understand DA dynamics and how these underlie discrete aspects of brain function. The methodological aspects of real-time DA detection at carbon-fiber microelectrodes using FSCV in anesthetized and awake animals are presented. Furthermore, the combination of FSCV with other neuroanalytical techniques is also explained. The advantages of FSCV and carbon-fiber microelectrodes can be expanded to the detection of non-electroactive analytes. This broadens the scope of FSCV such that it can be used to investigate how changes in non-electroactive chemicals underlie disease, cognition, and behavior. Carbon-fiber microelectrodes can be modified with an enzyme to monitor non-electroactive molecules, generating an electroactive product (usually hydrogen peroxide, H2O2). The first voltammetric detection of H2O 2 at bare carbon-fiber microelectrodes using FSCV has recently been reported. Thus, an avenue exists to utilize FSCV at enzyme-modified microelectrodes to voltammetrically identify and quantify non-electroactive analytes in real-time. Such an approach will overcome many limitations associated with the traditional amperometric detection scheme, which lacks electrochemical selectivity. Electrodeposition of the biopolymer chitosan with glucose oxidase (GOx) at the carbon surface yields a stable, sensitive, and selective glucose microbiosensor that has been utilized to detect glucose fluctuations in vivo with unprecedented speed. This new method has revealed the first rapid glucose fluctuations in

  4. Fiber-optic endoscopic evaluation of swallowing (FEES): predictor of swallowing-related complications in the head and neck cancer population.

    Science.gov (United States)

    Deutschmann, Michael W; McDonough, Alanna; Dort, Joseph C; Dort, Erika; Nakoneshny, Steve; Matthews, T Wayne

    2013-07-01

    The treatment of head and neck cancer is associated with significant dysphagia and morbidity. Prescribing a safe oral diet in this population is challenging. Data from 116 consecutive patients having 189 fiber-optic endoscopic evaluation of swallowing (FEES) examinations over a 3-year period were analyzed. All patients had been treated for head and neck cancer and subsequently were assessed by FEES. The primary outcome was the incidence of swallowing-related adverse events resulting from the FEES-based dietary recommendations. There were 10 episodes of aspiration pneumonia, 4 episodes of airway obstruction, 3 unanticipated insertions of gastrostomy tubes, and 2 unexplained deaths within the study period. The overall rate of adverse events was 10.1%. The only statistically significant predictor of adverse events was the Rosenbek score (p = .03). Our experience is that FEES guides appropriate and safe diet recommendations in this population. Copyright © 2012 Wiley Periodicals, Inc.

  5. Comparative study of the endoscope-based bevelled and volume fiber-optic Raman probes for optical diagnosis of gastric dysplasia in vivo at endoscopy.

    Science.gov (United States)

    Wang, Jianfeng; Lin, Kan; Zheng, Wei; Ho, Khek Yu; Teh, Ming; Yeoh, Khay Guan; Huang, Zhiwei

    2015-11-01

    This study aims to compare the diagnostic performance of the two different endoscope-based fiber-optic Raman probe designs (i.e., bevelled and volume Raman probes) for real-time, in vivo detection of gastric dysplasia at endoscopy. To conduct the clinical comparison, a total of 1,050 in vivo tissue Raman spectra (normal: n = 864; dysplasia: n = 186) were acquired from 66 gastric patients (normal: n = 48; dysplasia: n = 18) by using bevelled Raman probe, while a total of 1,913 in vivo tissue Raman spectra (normal: n = 1,786; dysplasia: n = 127) were acquired from 98 gastric patients (normal: n = 87; dysplasia: n = 11) by using volume Raman probe. The bevelled Raman probe provides approximately twofold improvements in tissue Raman-to-autofluorescence intensity ratios as compared to the use of volume Raman probe. Partial least squares discriminant analysis together with leave-one patient-out cross-validation on in vivo tissue Raman spectra acquired yields a diagnostic accuracy of 93.0 % (sensitivity of 92.5 %; specificity of 93.1 %) for differentiating gastric dysplasia from normal gastric tissue by using the bevelled fiber-optic Raman probe, which is superior to the diagnostic performance (accuracy of 88.4 %; sensitivity of 85.8 %; specificity of 88.6 %) by using the volume Raman probe. This work demonstrates that the Raman spectroscopic technique coupled with bevelled fiber-optic Raman probe has great potential to enhance in vivo diagnosis of gastric precancer and early cancer at endoscopy. Graphical Abstract Comparison of in vivo gastric tissue Raman spectra acquired by using bevelled and volume fiber-optic Raman probes.

  6. Endoscopic ultrasound duplex scanning for measurement of portal venous flow. Validation against transit time ultrasound flowmetry in pigs

    DEFF Research Database (Denmark)

    Hansen, E F; Strandberg, C; Bendtsen, F

    1999-01-01

    with that of transit time ultrasound (TTU) in healthy pigs. The ability of EUS to detect changes in the portal venous flow after pharmacologic intervention was also investigated. METHODS: Six anaesthetized pigs were studied. Portal venous flow was measured simultaneously by EUS duplex scanning, using a Pentax FG-32UA...... echoendoscope connected to a Hitachi EUB 515-A ultrasound scanner, and by TTU with a Cardiomed CM 4000 flowmeter probe placed on the portal vein. Terlipressin, 1 mg, and placebo were administered in a blind, randomized, crossover design. Measurements were taken at base line and 30 min after each drug...

  7. Rotational scanning and multiple-spot focusing through a multimode fiber based on digital optical phase conjugation

    Science.gov (United States)

    Ma, Chaojie; Di, Jianglei; Li, Ying; Xiao, Fajun; Zhang, Jiwei; Liu, Kaihui; Bai, Xuedong; Zhao, Jianlin

    2018-06-01

    We demonstrate, for the first time, the rotational memory effect of a multimode fiber (MMF) based on digital optical phase conjugation (DOPC) to achieve multiple-spot focusing. An implementation interferometer is used to address the challenging alignments in DOPC. By rotating the acquired phase conjugate pattern, rotational scanning through a MMF could be achieved by recording a single off-axis hologram. The generation of two focal spots through a MMF is also demonstrated by combining the rotational memory effect with the superposition principle. The results may be useful for ultrafast scanning imaging and optical manipulation of multiple objects through a MMF.

  8. Thulium fiber laser for the use in low-invasive endoscopic and robotic surgery of soft biological tissues

    Science.gov (United States)

    Michalska, M.; Brojek, W.; Rybak, Z.; Sznelewski, P.; Mamajek, M.; Gogler, S.; Swiderski, J.

    2016-12-01

    An all-fiber, diode-pumped, continuous-wave Tm3+-doped fiber laser operated at a wavelength of 1.94 μm was developed. 37.4 W of output power with a slope efficiency as high as 57% with respect to absorbed pump power at 790 nm was demonstrated. The laser output beam quality factor M2 was measured to be 1.2. The output beam was very stable with power fluctuations surgery of soft biological tissues.

  9. Assessment of cumulative damage by using ultrasonic C-scan on carbon fiber/epoxy composites under thermal cycling

    Directory of Open Access Journals (Sweden)

    Marcos Yutaka Shiino

    2012-08-01

    Full Text Available In recent years, structural composites manufactured by carbon fiber/epoxy laminates have been employed in large scale in aircraft industries. These structures require high strength under severe temperature changes of -56° until 80 °C. Regarding this scenario, the aim of this research was to reproduce thermal stress in the laminate plate developed by temperature changes and tracking possible cumulative damages on the laminate using ultrasonic C-scan inspection. The evaluation was based on attenuation signals and the C-scan map of the composite plate. The carbon fiber/epoxy plain weave laminate underwent temperatures of -60° to 80 °C, kept during 10 minutes and repeated for 1000, 2000, 3000 and 4000 times. After 1000 cycles, the specimens were inspected by C-scanning. A few changes in the laminate were observed using the inspection methodology only in specimens cycled 3000 times, or so. According to the found results, the used temperature range did not present enough conditions to cumulative damage in this type of laminate, which is in agreement with the macro - and micromechanical theory.

  10. Oxidation of hydrogen-passivated silicon surfaces by scanning near-field optical lithography using uncoated and aluminum-coated fiber probes

    DEFF Research Database (Denmark)

    Madsen, Steen; Bozhevolnyi, Sergey I.; Birkelund, Karen

    1997-01-01

    Optically induced oxidation of hydrogen-passivated silicon surfaces using a scanning near-field optical microscope was achieved with both uncoated and aluminum-coated fiber probes. Line scans on amorphous silicon using uncoated fiber probes display a three-peak profile after etching in potassium...... hydroxide. Numerical simulations of the electromagnetic field around the probe-sample interaction region are used to explain the experimental observations. With an aluminum-coated fiber probe, lines of 35 nm in width were transferred into the amorphous silicon layer. (C) 1997 American Institute of Physics....

  11. Evaluation of retinal nerve fiber layer thickness parameters in myopic population using scanning laser polarimetry (GDxVCC).

    Science.gov (United States)

    Dada, Tanuj; Aggarwal, A; Bali, S J; Sharma, A; Shah, B M; Angmo, D; Panda, A

    2013-01-01

    Myopia presents a significant challenge to the ophthalmologist as myopic discs are often large, tilted, with deep cups and have a thinner neuroretinal rim all of which may mimic glaucomatous optic nerve head changes causing an error in diagnosis. To evaluate the retinal fiber layer (RNFL) thickness in low, moderate and high myopia using scanning laser polarimetry with variable corneal compensation (GDxVCC). One hundred eyes of 100 emmetropes, 30 eyes of low myopes (0 to - 4 D spherical equivalent(SE), 45 eyes with moderate myopia (- 4 to - 8D SE), and 30 eyes with high myopia (- 8 to - 15D SE) were subjected to retinal nerve fiber layer assessment using the scanning laser polarimetry (GDxVCC) in all subjects using the standard protocol. Subjects with IOP > 21 mm Hg, optic nerve head or visual field changes suggestive of glaucoma were excluded from the study. The major outcome parameters were temporal-superior-nasal-inferiortemporal (TSNIT) average, the superior and inferior average and the nerve fibre indicator (NFI). The TSNIT average (p = 0.009), superior (p = 0.001) and inferior average (p = 0.008) were significantly lower; the NFI was higher (P less than 0.001) in moderate myopes as compared to that in emmetropes. In high myopia the RNFL showed supranormal values; the TSNIT average, superior and inferior average was significantly higher(p less than 0.001) as compared to that in emmetropes. The RNFL measurements on scanning laser polarimetry are affected by the myopic refractive error. Moderate myopes show a significant thinning of the RNFL. In high myopia due to peripapillary chorioretinal atrophy and contribution of scleral birefringence, the RNFL values are abnormally high. These findings need to be taken into account while assessing and monitoring glaucoma damage in moderate to high myopes on GDxVCC. © NEPjOPH.

  12. Hypodense regions (holes) in the retinal nerve fiber layer in frequency-domain OCT scans of glaucoma patients and suspects.

    Science.gov (United States)

    Xin, Daiyan; Talamini, Christine L; Raza, Ali S; de Moraes, Carlos Gustavo V; Greenstein, Vivienne C; Liebmann, Jeffrey M; Ritch, Robert; Hood, Donald C

    2011-09-09

    To better understand hypodense regions (holes) that appear in the retinal nerve fiber layer (RNFL) of frequency-domain optical coherence tomography (fdOCT) scans of patients with glaucoma and glaucoma suspects. Peripapillary circle (1.7-mm radius) and cube optic disc fdOCT scans were obtained on 208 eyes from 110 patients (57.4 ± 13.2 years) with glaucomatous optic neuropathy (GON) and 45 eyes of 45 controls (48.0 ± 12.6 years) with normal results of fundus examination. Holes in the RNFL were identified independently by two observers on the circle scans. Holes were found in 33 (16%) eyes of 28 (25%) patients; they were not found in any of the control eyes. Twenty-four eyes had more than one hole. Although some holes were relatively large, others were small. In general, the holes were located adjacent to blood vessels; only three eyes had isolated holes that were not adjacent to a vessel. The holes tended to be in the regions that are thickest in healthy controls and were associated with arcuate defects in patients. Holes were not seen in the center of the temporal disc region. They were more common in the superior (25 eyes) than in the inferior (15 eyes) disc. Of the 30 eyes with holes with reliable visual fields, seven were glaucoma suspect eyes with normal visual fields. The holes in the RNFL seen in patients with GON were probably due to a local loss of RNFL fibers and can occur in the eyes of glaucoma suspects with normal visual fields.

  13. Confocal Adaptive Optics Imaging of Peripapillary Nerve Fiber Bundles: Implications for Glaucomatous Damage Seen on Circumpapillary OCT Scans.

    Science.gov (United States)

    Hood, Donald C; Chen, Monica F; Lee, Dongwon; Epstein, Benjamin; Alhadeff, Paula; Rosen, Richard B; Ritch, Robert; Dubra, Alfredo; Chui, Toco Y P

    2015-04-01

    To improve our understanding of glaucomatous damage as seen on circumpapillary disc scans obtained with frequency-domain optical coherence tomography (fdOCT), fdOCT scans were compared to images of the peripapillary retinal nerve fiber (RNF) bundles obtained with an adaptive optics-scanning light ophthalmoscope (AO-SLO). The AO-SLO images and fdOCT scans were obtained on 6 eyes of 6 patients with deep arcuate defects (5 points ≤-15 db) on 10-2 visual fields. The AO-SLO images were montaged and aligned with the fdOCT images to compare the RNF bundles seen with AO-SLO to the RNF layer thickness measured with fdOCT. All 6 eyes had an abnormally thin (1% confidence limit) RNF layer (RNFL) on fdOCT and abnormal (hyporeflective) regions of RNF bundles on AO-SLO in corresponding regions. However, regions of abnormal, but equal, RNFL thickness on fdOCT scans varied in appearance on AO-SLO images. These regions could be largely devoid of RNF bundles (5 eyes), have abnormal-appearing bundles of lower contrast (6 eyes), or have isolated areas with a few relatively normal-appearing bundles (2 eyes). There also were local variations in reflectivity of the fdOCT RNFL that corresponded to the variations in AO-SLO RNF bundle appearance. Relatively similar 10-2 defects with similar fdOCT RNFL thickness profiles can have very different degrees of RNF bundle damage as seen on fdOCT and AO-SLO. While the results point to limitations of fdOCT RNFL thickness as typically analyzed, they also illustrate the potential for improving fdOCT by attending to variations in local intensity.

  14. Full optical model of micro-endoscope with optical coherence microscopy, multiphoton microscopy and visible capabilities

    Science.gov (United States)

    Vega, David; Kiekens, Kelli C.; Syson, Nikolas C.; Romano, Gabriella; Baker, Tressa; Barton, Jennifer K.

    2018-02-01

    While Optical Coherence Microscopy (OCM), Multiphoton Microscopy (MPM), and narrowband imaging are powerful imaging techniques that can be used to detect cancer, each imaging technique has limitations when used by itself. Combining them into an endoscope to work in synergy can help achieve high sensitivity and specificity for diagnosis at the point of care. Such complex endoscopes have an elevated risk of failure, and performing proper modelling ensures functionality and minimizes risk. We present full 2D and 3D models of a multimodality optical micro-endoscope to provide real-time detection of carcinomas, called a salpingoscope. The models evaluate the endoscope illumination and light collection capabilities of various modalities. The design features two optical paths with different numerical apertures (NA) through a single lens system with a scanning optical fiber. The dual path is achieved using dichroic coatings embedded in a triplet. A high NA optical path is designed to perform OCM and MPM while a low NA optical path is designed for the visible spectrum to navigate the endoscope to areas of interest and narrowband imaging. Different tests such as the reflectance profile of homogeneous epithelial tissue were performed to adjust the models properly. Light collection models for the different modalities were created and tested for efficiency. While it is challenging to evaluate the efficiency of multimodality endoscopes, the models ensure that the system is design for the expected light collection levels to provide detectable signal to work for the intended imaging.

  15. Endoscopic retrograde cholangiopancreatography and endoscopic ...

    African Journals Online (AJOL)

    An approach to suspected gallstone pancreatitis'based on endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (ES) was adopted in 1976 and was followed in 29 patients. ERCp became the routine method of early biliary tract assessment when gallstone pancreatitis was suspected on ...

  16. Improved image quality of cone beam CT scans for radiotherapy image guidance using fiber-interspaced antiscatter grid.

    Science.gov (United States)

    Stankovic, Uros; van Herk, Marcel; Ploeger, Lennert S; Sonke, Jan-Jakob

    2014-06-01

    Medical linear accelerator mounted cone beam CT (CBCT) scanner provides useful soft tissue contrast for purposes of image guidance in radiotherapy. The presence of extensive scattered radiation has a negative effect on soft tissue visibility and uniformity of CBCT scans. Antiscatter grids (ASG) are used in the field of diagnostic radiography to mitigate the scatter. They usually do increase the contrast of the scan, but simultaneously increase the noise. Therefore, and considering other scatter mitigation mechanisms present in a CBCT scanner, the applicability of ASGs with aluminum interspacing for a wide range of imaging conditions has been inconclusive in previous studies. In recent years, grids using fiber interspacers have appeared, providing grids with higher scatter rejection while maintaining reasonable transmission of primary radiation. The purpose of this study was to evaluate the impact of one such grid on CBCT image quality. The grid used (Philips Medical Systems) had ratio of 21:1, frequency 36 lp/cm, and nominal selectivity of 11.9. It was mounted on the kV flat panel detector of an Elekta Synergy linear accelerator and tested in a phantom and a clinical study. Due to the flex of the linac and presence of gridline artifacts an angle dependent gain correction algorithm was devised to mitigate resulting artifacts. Scan reconstruction was performed using XVI4.5 augmented with inhouse developed image lag correction and Hounsfield unit calibration. To determine the necessary parameters for Hounsfield unit calibration and software scatter correction parameters, the Catphan 600 (The Phantom Laboratory) phantom was used. Image quality parameters were evaluated using CIRS CBCT Image Quality and Electron Density Phantom (CIRS) in two different geometries: one modeling head and neck and other pelvic region. Phantoms were acquired with and without the grid and reconstructed with and without software correction which was adapted for the different acquisition

  17. Improved image quality of cone beam CT scans for radiotherapy image guidance using fiber-interspaced antiscatter grid

    International Nuclear Information System (INIS)

    Stankovic, Uros; Herk, Marcel van; Ploeger, Lennert S.; Sonke, Jan-Jakob

    2014-01-01

    Purpose: Medical linear accelerator mounted cone beam CT (CBCT) scanner provides useful soft tissue contrast for purposes of image guidance in radiotherapy. The presence of extensive scattered radiation has a negative effect on soft tissue visibility and uniformity of CBCT scans. Antiscatter grids (ASG) are used in the field of diagnostic radiography to mitigate the scatter. They usually do increase the contrast of the scan, but simultaneously increase the noise. Therefore, and considering other scatter mitigation mechanisms present in a CBCT scanner, the applicability of ASGs with aluminum interspacing for a wide range of imaging conditions has been inconclusive in previous studies. In recent years, grids using fiber interspacers have appeared, providing grids with higher scatter rejection while maintaining reasonable transmission of primary radiation. The purpose of this study was to evaluate the impact of one such grid on CBCT image quality. Methods: The grid used (Philips Medical Systems) had ratio of 21:1, frequency 36 lp/cm, and nominal selectivity of 11.9. It was mounted on the kV flat panel detector of an Elekta Synergy linear accelerator and tested in a phantom and a clinical study. Due to the flex of the linac and presence of gridline artifacts an angle dependent gain correction algorithm was devised to mitigate resulting artifacts. Scan reconstruction was performed using XVI4.5 augmented with inhouse developed image lag correction and Hounsfield unit calibration. To determine the necessary parameters for Hounsfield unit calibration and software scatter correction parameters, the Catphan 600 (The Phantom Laboratory) phantom was used. Image quality parameters were evaluated using CIRS CBCT Image Quality and Electron Density Phantom (CIRS) in two different geometries: one modeling head and neck and other pelvic region. Phantoms were acquired with and without the grid and reconstructed with and without software correction which was adapted for the different

  18. Effect of cataract surgery on retinal nerve fiber layer thickness parameters using scanning laser polarimetry (GDxVCC).

    Science.gov (United States)

    Dada, Tanuj; Behera, Geeta; Agarwal, Anand; Kumar, Sanjeev; Sihota, Ramanjit; Panda, Anita

    2010-01-01

    To study the effect of cataract extraction on the retinal nerve fiber layer (RNFL) thickness, and assessment by scanning laser polarimetry (SLP), with variable corneal compensation (GDx VCC), at the glaucoma service of a tertiary care center in North India. Thirty-two eyes of 32 subjects were enrolled in the study. The subjects underwent RNFL analysis by SLP (GDx VCC) before undergoing phacoemulsification cataract extraction with intraocular lens (IOL) implantation (Acrysof SA 60 AT) four weeks following cataract surgery. The RNFL thickness parameters evaluated both before and after surgery included temporal, superior, nasal, inferior, temporal (TSNIT) average, superior average, inferior average, and nerve fiber index (NFI). The mean age of subjects was 57.6 +/- 11.7 years (18 males, 14 females). Mean TSNIT average thickness (microm) pre- and post-cataract surgery was 49.2 +/- 14.1 and 56.5 +/- 7.6 ( P = 0.001). There was a statistically significant increase in RNFL thickness parameters (TSNIT average, superior average, and inferior average) and decrease in NFI post-cataract surgery as compared to the baseline values. Mean NFI pre- and post-cataract surgery was 41.3 +/- 15.3 and 21.6 +/- 11.8 ( P = 0.001). Measurement of RNFL thickness parameters by scanning laser polarimetry is significantly altered following cataract surgery. Post the cataract surgery, a new baseline needs to be established for assessing the longitudinal follow-up of a glaucoma patient. The presence of cataract may lead to an underestimation of the RNFL thickness, and this should be taken into account when analyzing progression in a glaucoma patient.

  19. Non-scanning fiber-optic near-infrared beam led to two-photon optogenetic stimulation in-vivo.

    Directory of Open Access Journals (Sweden)

    Kamal R Dhakal

    Full Text Available Stimulation of specific neurons expressing opsins in a targeted region to manipulate brain function has proved to be a powerful tool in neuroscience. However, the use of visible light for optogenetic stimulation is invasive due to low penetration depth and tissue damage owing to larger absorption and scattering. Here, we report, for the first time, in-depth non-scanning fiber-optic two-photon optogenetic stimulation (FO-TPOS of neurons in-vivo in transgenic mouse models. In order to optimize the deep-brain stimulation strategy, we characterized two-photon activation efficacy at different near-infrared laser parameters. The significantly-enhanced in-depth stimulation efficiency of FO-TPOS as compared to conventional single-photon beam was demonstrated both by experiments and Monte Carlo simulation. The non-scanning FO-TPOS technology will lead to better understanding of the in-vivo neural circuitry because this technology permits more precise and less invasive anatomical delivery of stimulation.

  20. Detection of Progressive Retinal Nerve Fiber Layer Loss in Glaucoma Using Scanning Laser Polarimetry with Variable Corneal Compensation

    Science.gov (United States)

    Medeiros, Felipe A.; Alencar, Luciana M.; Zangwill, Linda M.; Bowd, Christopher; Vizzeri, Gianmarco; Sample, Pamela A.; Weinreb, Robert N.

    2010-01-01

    Purpose To evaluate the ability of scanning laser polarimetry with variable corneal compensation to detect progressive retinal nerve fiber layer (RNFL) loss in glaucoma patients and patients suspected of having the disease. Methods This was an observational cohort study that included 335 eyes of 195 patients. Images were obtained annually with the GDx VCC scanning laser polarimeter, along with optic disc stereophotographs and standard automated perimetry (SAP) visual fields. The median follow-up time was 3.94 years. Progression was determined using commercial software for SAP and by masked assessment of optic disc stereophotographs performed by expert graders. Random coefficient models were used to evaluate the relationship between RNFL thickness measurements over time and progression as determined by SAP and/or stereophotographs. Results From the 335 eyes, 34 (10%) showed progression over time by stereophotographs and/or SAP. Average GDx VCC measurements decreased significantly over time for both progressors as well as non-progressors. However, the rate of decline was significantly higher in the progressing group (−0.70 μm/year) compared to the non-progressing group (−0.14 μm/year; P = 0.001). Black race and male sex were significantly associated with higher rates of RNFL loss during follow-up. Conclusions The GDx VCC scanning laser polarimeter was able to identify longitudinal RNFL loss in eyes that showed progression in optic disc stereophotographs and/or visual fields. These findings suggest that this technology could be useful to detect and monitor progressive disease in patients with established diagnosis of glaucoma or suspected of having the disease. PMID:19029038

  1. Improved path imbalance measurement of a fiber-optic interferometer based on frequency scanning interferometry

    International Nuclear Information System (INIS)

    Hou, C B; Wang, J G; Yang, J; Li, H Y; Peng, F; Yuan, L B; Yuan, Y G

    2017-01-01

    We developed a path imbalance measuring system using a reference interferometer with alterable optical path difference (OPD), aiming to eliminate the uncertainties due to synthetic wavelength measurement and remove the requirement of a known and stable reference OPD in frequency scanning interferometry. The path imbalance can be solved by using the phase ratios between the two interferometers produced before and after altering the OPD in the reference interferometer. The results have shown that the measurement uncertainty and the path imbalance are linearly related and a combined relative uncertainty of 4.9  ×  10 −6 (1 σ ) in path imbalance measurement over a range from 0.5 m to 50 m is achieved. Besides, we analyzed the contributions to the uncertainty that limit the performance of the system, and we discussed how to obtain a better measurement uncertainty. (paper)

  2. High-resolution imaging of the retinal nerve fiber layer in normal eyes using adaptive optics scanning laser ophthalmoscopy.

    Science.gov (United States)

    Takayama, Kohei; Ooto, Sotaro; Hangai, Masanori; Arakawa, Naoko; Oshima, Susumu; Shibata, Naohisa; Hanebuchi, Masaaki; Inoue, Takashi; Yoshimura, Nagahisa

    2012-01-01

    To conduct high-resolution imaging of the retinal nerve fiber layer (RNFL) in normal eyes using adaptive optics scanning laser ophthalmoscopy (AO-SLO). AO-SLO images were obtained in 20 normal eyes at multiple locations in the posterior polar area and a circular path with a 3-4-mm diameter around the optic disc. For each eye, images focused on the RNFL were recorded and a montage of AO-SLO images was created. AO-SLO images for all eyes showed many hyperreflective bundles in the RNFL. Hyperreflective bundles above or below the fovea were seen in an arch from the temporal periphery on either side of a horizontal dividing line to the optic disc. The dark lines among the hyperreflective bundles were narrower around the optic disc compared with those in the temporal raphe. The hyperreflective bundles corresponded with the direction of the striations on SLO red-free images. The resolution and contrast of the bundles were much higher in AO-SLO images than in red-free fundus photography or SLO red-free images. The mean hyperreflective bundle width around the optic disc had a double-humped shape; the bundles at the temporal and nasal sides of the optic disc were narrower than those above and below the optic disc (Poptical coherence tomography correlated with the hyperreflective bundle widths on AO-SLO (Pfiber bundles and Müller cell septa. The widths of the nerve fiber bundles appear to be proportional to the RNFL thickness at equivalent distances from the optic disc.

  3. Scanning electron microscopy of real and artificial kidney stones before and after Thulium fiber laser ablation in air and water

    Science.gov (United States)

    Hardy, Luke A.; Irby, Pierce B.; Fried, Nathaniel M.

    2018-02-01

    We investigated proposed mechanisms of laser lithotripsy, specifically for the novel, experimental Thulium fiber laser (TFL). Previous lithotripsy studies with the conventional Holmium:YAG laser noted a primary photothermal mechanism (vaporization). Our hypothesis is that an additional mechanical effect (fragmentation) occurs due to vaporization of water in stone material from high absorption of energy, called micro-explosions. The TFL irradiated calcium oxalate monohydrate (COM) and uric acid (UA) stones, as well as artificial stones (Ultracal30 and BegoStone), in air and water environments. TFL energy was varied to determine the relative effect on the ablation mechanism. Scanning electron microscopy (SEM) was used to study qualitative and characteristic changes in surface topography with correlation to presumed ablation mechanisms. Laser irradiation of stones in air produced charring and melting of the stone surface consistent with a photothermal effect and minimal fragmentation, suggesting no mechanical effect from micro-explosions. For COM stones ablated in water, there was prominent fragmentation in addition to recognized photothermal effects, supporting dual mechanisms during TFL lithotripsy. For UA stones, there were minimal photothermal effects, and dominant effects were mechanical. By increasing TFL pulse energy, a greater mechanical effect was demonstrated for both stone types. For artificial stones, there was no significant evidence of mechanical effects. TFL laser lithotripsy relies on two prominent mechanisms for stone ablation, photothermal and mechanical. Water is necessary for the mechanical effect which can be augmented by increasing pulse energy. Artificial stones may not provide a predictive model for mechanical effects during laser lithotripsy.

  4. Run-to-Run Optimization Control Within Exact Inverse Framework for Scan Tracking.

    Science.gov (United States)

    Yeoh, Ivan L; Reinhall, Per G; Berg, Martin C; Chizeck, Howard J; Seibel, Eric J

    2017-09-01

    A run-to-run optimization controller uses a reduced set of measurement parameters, in comparison to more general feedback controllers, to converge to the best control point for a repetitive process. A new run-to-run optimization controller is presented for the scanning fiber device used for image acquisition and display. This controller utilizes very sparse measurements to estimate a system energy measure and updates the input parameterizations iteratively within a feedforward with exact-inversion framework. Analysis, simulation, and experimental investigations on the scanning fiber device demonstrate improved scan accuracy over previous methods and automatic controller adaptation to changing operating temperature. A specific application example and quantitative error analyses are provided of a scanning fiber endoscope that maintains high image quality continuously across a 20 °C temperature rise without interruption of the 56 Hz video.

  5. Fiber

    Science.gov (United States)

    ... meals instead of white rice. Add beans (kidney, black, navy, and pinto) to rice dishes for even more fiber. Spice up salads with berries and almonds, chickpeas, cooked artichokes, and beans (kidney, black, navy, or pinto). Use whole-grain (corn or ...

  6. Relevance Vector Machine and Support Vector Machine Classifier Analysis of Scanning Laser Polarimetry Retinal Nerve Fiber Layer Measurements

    Science.gov (United States)

    Bowd, Christopher; Medeiros, Felipe A.; Zhang, Zuohua; Zangwill, Linda M.; Hao, Jiucang; Lee, Te-Won; Sejnowski, Terrence J.; Weinreb, Robert N.; Goldbaum, Michael H.

    2010-01-01

    Purpose To classify healthy and glaucomatous eyes using relevance vector machine (RVM) and support vector machine (SVM) learning classifiers trained on retinal nerve fiber layer (RNFL) thickness measurements obtained by scanning laser polarimetry (SLP). Methods Seventy-two eyes of 72 healthy control subjects (average age = 64.3 ± 8.8 years, visual field mean deviation =−0.71 ± 1.2 dB) and 92 eyes of 92 patients with glaucoma (average age = 66.9 ± 8.9 years, visual field mean deviation =−5.32 ± 4.0 dB) were imaged with SLP with variable corneal compensation (GDx VCC; Laser Diagnostic Technologies, San Diego, CA). RVM and SVM learning classifiers were trained and tested on SLP-determined RNFL thickness measurements from 14 standard parameters and 64 sectors (approximately 5.6° each) obtained in the circumpapillary area under the instrument-defined measurement ellipse (total 78 parameters). Tenfold cross-validation was used to train and test RVM and SVM classifiers on unique subsets of the full 164-eye data set and areas under the receiver operating characteristic (AUROC) curve for the classification of eyes in the test set were generated. AUROC curve results from RVM and SVM were compared to those for 14 SLP software-generated global and regional RNFL thickness parameters. Also reported was the AUROC curve for the GDx VCC software-generated nerve fiber indicator (NFI). Results The AUROC curves for RVM and SVM were 0.90 and 0.91, respectively, and increased to 0.93 and 0.94 when the training sets were optimized with sequential forward and backward selection (resulting in reduced dimensional data sets). AUROC curves for optimized RVM and SVM were significantly larger than those for all individual SLP parameters. The AUROC curve for the NFI was 0.87. Conclusions Results from RVM and SVM trained on SLP RNFL thickness measurements are similar and provide accurate classification of glaucomatous and healthy eyes. RVM may be preferable to SVM, because it provides a

  7. Retinal nerve fiber layer analysis with scanning laser polarimetry and RTVue-OCT in patients of retinitis pigmentosa.

    Science.gov (United States)

    Xue, Kang; Wang, Min; Chen, Junyi; Huang, Xin; Xu, Gezhi

    2013-01-01

    To measure the thickness of the retinal nerve fiber layer (RNFL) of patients with retinitis pigmentosa (RP) and that of normal controls by scanning laser polarimetry with enhanced corneal compensation (GDxECC) and RTVue-optical coherence tomography (OCT). Fifty-two eyes of 26 patients were included. All patients underwent complete ophthalmological examinations and testing with GDxECC. Twenty-eight of 52 eyes of RP patients underwent RTVue-OCT measurements. A group of 50 eyes of 25 normal subjects (controls) was also included. GDxECC measured RNFL thickness in the peripapillary area in all subjects as well as temporal-superior-nasal-inferior-temporal (TSNIT) parameters, including TSNIT means, superior and inferior region means, TSNIT standard deviation (SD), inter-eye symmetry and nerve fiber indicator (NFI). RTVue-OCT measured the mean, superior, inferior, temporal and nasal quadrant RNFL thickness. In RP patients and controls, TSNIT means by GDxECC were, respectively, 65.00 ± 7.35 and 55.32 ± 5.20. Mean superior quadrant thicknesses were 80.56 ± 10.93 and 69.54 ± 7.45. Mean inferior thicknesses were 80.58 ± 9.34 and 69.12 ± 7.78. SDs were 27.92 ± 5.21 and 28.23 ± 4.01. Inter-eye symmetries were 0.82 ± 0.17 and 0.87 ± 0.09. NFIs were 9.74 ± 8.73 and 16.81 ± 8.13. The differences between mean TSNIT, mean superior and mean inferior quadrant thicknesses and NFIs were statistically significant (p < 0.001). In RTVue-OCT measurements, the differences between mean, superior, inferior and temporal quadrant RNFL thicknesses were statistically significant (p = 0.0322, 0.0213, 0.0387, 0.0005). The RNFL measured by GDxECC was significantly thicker in RP patients than in controls. RNFL thickness measured by RTVue-OCT was significantly greater in RP patients than in controls in the superior, inferior and temporal regions. This contribution provides information on RNFL thickness and discusses the mechanism underlying this phenomenon. Copyright © 2012 S. Karger AG

  8. Current Status of Peroral Endoscopic Myotomy

    OpenAIRE

    Cho, Young Kwan; Kim, Seong Hwan

    2018-01-01

    Peroral endoscopic myotomy (POEM) has been established as an optional treatment for achalasia. POEM is an endoluminal procedure that involves dissection of esophageal muscle fibers followed by submucosal tunneling. Inoue first attempted to use POEM for the treatment of achalasia in humans. Expanded indications of POEM include classic indications such as type I, type II, type III achalasia, failed prior treatments, including Botulinum toxin injection, endoscopic balloon dilation, laparoscopic ...

  9. Glaucoma progression detection by retinal nerve fiber layer measurement using scanning laser polarimetry: event and trend analysis.

    Science.gov (United States)

    Moon, Byung Gil; Sung, Kyung Rim; Cho, Jung Woo; Kang, Sung Yong; Yun, Sung-Cheol; Na, Jung Hwa; Lee, Youngrok; Kook, Michael S

    2012-06-01

    To evaluate the use of scanning laser polarimetry (SLP, GDx VCC) to measure the retinal nerve fiber layer (RNFL) thickness in order to evaluate the progression of glaucoma. Test-retest measurement variability was determined in 47 glaucomatous eyes. One eye each from 152 glaucomatous patients with at least 4 years of follow-up was enrolled. Visual field (VF) loss progression was determined by both event analysis (EA, Humphrey guided progression analysis) and trend analysis (TA, linear regression analysis of the visual field index). SLP progression was defined as a reduction of RNFL exceeding the predetermined repeatability coefficient in three consecutive exams, as compared to the baseline measure (EA). The slope of RNFL thickness change over time was determined by linear regression analysis (TA). Twenty-two eyes (14.5%) progressed according to the VF EA, 16 (10.5%) by VF TA, 37 (24.3%) by SLP EA and 19 (12.5%) by SLP TA. Agreement between VF and SLP progression was poor in both EA and TA (VF EA vs. SLP EA, k = 0.110; VF TA vs. SLP TA, k = 0.129). The mean (±standard deviation) progression rate of RNFL thickness as measured by SLP TA did not significantly differ between VF EA progressors and non-progressors (-0.224 ± 0.148 µm/yr vs. -0.218 ± 0.151 µm/yr, p = 0.874). SLP TA and EA showed similar levels of sensitivity when VF progression was considered as the reference standard. RNFL thickness as measurement by SLP was shown to be capable of detecting glaucoma progression. Both EA and TA of SLP showed poor agreement with VF outcomes in detecting glaucoma progression.

  10. Characterization of power induced heating and damage in fiber optic probes for near-field scanning optical microscopy

    Science.gov (United States)

    Dickenson, Nicholas E.; Erickson, Elizabeth S.; Mooren, Olivia L.; Dunn, Robert C.

    2007-05-01

    Tip-induced sample heating in near-field scanning optical microscopy (NSOM) is studied for fiber optic probes fabricated using the chemical etching technique. To characterize sample heating from etched NSOM probes, the spectra of a thermochromic polymer sample are measured as a function of probe output power, as was previously reported for pulled NSOM probes. The results reveal that sample heating increases rapidly to ˜55-60°C as output powers reach ˜50nW. At higher output powers, the sample heating remains approximately constant up to the maximum power studied of ˜450nW. The sample heating profiles measured for etched NSOM probes are consistent with those previously measured for NSOM probes fabricated using the pulling method. At high powers, both pulled and etched NSOM probes fail as the aluminum coating is damaged. For probes fabricated in our laboratory we find failure occurring at input powers of 3.4±1.7 and 20.7±6.9mW for pulled and etched probes, respectively. The larger half-cone angle for etched probes (˜15° for etched and ˜6° for pulled probes) enables more light delivery and also apparently leads to a different failure mechanism. For pulled NSOM probes, high resolution images of NSOM probes as power is increased reveal the development of stress fractures in the coating at a taper diameter of ˜6μm. These stress fractures, arising from the differential heating expansion of the dielectric and the metal coating, eventually lead to coating removal and probe failure. For etched tips, the absence of clear stress fractures and the pooled morphology of the damaged aluminum coating following failure suggest that thermal damage may cause coating failure, although other mechanisms cannot be ruled out.

  11. Miniaturized Fourier-plane fiber scanner for OCT endoscopy

    International Nuclear Information System (INIS)

    Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans

    2017-01-01

    A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool. (paper)

  12. Miniaturized Fourier-plane fiber scanner for OCT endoscopy

    Science.gov (United States)

    Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans

    2017-10-01

    A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool.

  13. Endoscopic laser-urethroplasty

    Science.gov (United States)

    Gilbert, Peter

    2006-02-01

    The objective was to prove the advantage of endoscopic laser-urethroplasty over internal urethrotomy in acquired urethral strictures. Patients and Method: From January, 1996 to June, 2005, 35 patients with a mean age of 66 years were submitted to endoscopic laser-urethroplasty for strictures of either the bulbar (30) or membranous (5) urethra. The operations were carried out under general anesthesia. First of all, the strictures were incised at the 4, 8 and 12 o'clock position by means of a Sachse-urethrotom. Then the scar flap between the 4 and 8 o'clock position was vaporized using a Nd:YAG laser, wavelength 1060 nm and a 600 pm bare fiber, the latter always being in contact with the tissue. The laser worked at 40W power in continuous mode. The total energy averaged 2574 J. An indwelling catheter was kept in place overnight and the patients were discharged the following day. Urinalysis, uroflowmetry and clinical examination were performed at two months after surgery and from then on every six months. Results: No serious complications were encountered. Considering a mean follow-up of 18 months, the average peak flow improved from 7.3 ml/s preoperatively to 18.7 mVs postoperatively. The treatment faded in 5 patients ( 14.3% ) who finally underwent open urethroplasty. Conclusions: Endoscopic laser-urethroplasty yields better short-term results than internal visual urethrotomy. Long-term follow-up has yet to confirm its superiority in the treatment of acquired urethral strictures.

  14. Repeatability and Reproducibility of Retinal Nerve Fiber Layer Parameters Measured by Scanning Laser Polarimetry with Enhanced Corneal Compensation in Normal and Glaucomatous Eyes.

    Science.gov (United States)

    Ara, Mirian; Ferreras, Antonio; Pajarin, Ana B; Calvo, Pilar; Figus, Michele; Frezzotti, Paolo

    2015-01-01

    To assess the intrasession repeatability and intersession reproducibility of peripapillary retinal nerve fiber layer (RNFL) thickness parameters measured by scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) in healthy and glaucomatous eyes. One randomly selected eye of 82 healthy individuals and 60 glaucoma subjects was evaluated. Three scans were acquired during the first visit to evaluate intravisit repeatability. A different operator obtained two additional scans within 2 months after the first session to determine intervisit reproducibility. The intraclass correlation coefficient (ICC), coefficient of variation (COV), and test-retest variability (TRT) were calculated for all SLP parameters in both groups. ICCs ranged from 0.920 to 0.982 for intravisit measurements and from 0.910 to 0.978 for intervisit measurements. The temporal-superior-nasal-inferior-temporal (TSNIT) average was the highest (0.967 and 0.946) in normal eyes, while nerve fiber indicator (NFI; 0.982) and inferior average (0.978) yielded the best ICC in glaucomatous eyes for intravisit and intervisit measurements, respectively. All COVs were under 10% in both groups, except NFI. TSNIT average had the lowest COV (2.43%) in either type of measurement. Intervisit TRT ranged from 6.48 to 12.84. The reproducibility of peripapillary RNFL measurements obtained with SLP-ECC was excellent, indicating that SLP-ECC is sufficiently accurate for monitoring glaucoma progression.

  15. The influence of glass fibers on the morphology of β-nucleated isotactic polypropylene evaluated by differential scanning calorimetry

    Directory of Open Access Journals (Sweden)

    Janevski Aco

    2015-01-01

    Full Text Available The presence of fillers/fibers can significantly affect the polymorphic behavior of semi-crystalline polymers. The influence of glass fibers on morphology of β-nucleated iPP during isothermal and nonisothermal crystallization was analyzed in detail by DSC, and the kinetics and thermodynamic parameters were determined for the systems containing 10-60 % glass fibers. The presence of glass fibers in model composites with β-iPP has insignificant effect on the morphology of the polymer. Thermodynamic and kinetics parameters of crystallization of iPP in model composites are close to those obtained for the nucleated polymer. The relative content of β-crystalline phase is slightly affected by increasing glass fiber’s content from 10 % mas to 60 % mas, due to appearance of α-crystallites. However, the stability of β-crystalline phase is decreased by the increasing glass fibers content and there appeared certain amount of β1 and β2 phases which are known as disposed to recrystallization.

  16. Fabrication and characterization of a nanometer-sized optical fiber electrode based on selective chemical etching for scanning electrochemical/optical microscopy.

    Science.gov (United States)

    Maruyama, Kenichi; Ohkawa, Hiroyuki; Ogawa, Sho; Ueda, Akio; Niwa, Osamu; Suzuki, Koji

    2006-03-15

    We have already reported a method for fabricating ultramicroelectrodes (Suzuki, K. JP Patent, 2004-45394, 2004). This method is based on the selective chemical etching of optical fibers. In this work, we undertake a detailed investigation involving a combination of etched optical fibers with various types of tapered tip (protruding-shape, double- (or pencil-) shape and triple-tapered electrode) and insulation with electrophoretic paint. Our goal is to establish a method for fabricating nanometer-sized optical fiber electrodes with high reproducibility. As a result, we realized pencil-shaped and triple-tapered electrodes that had radii in the nanometer range with high reproducibility. These nanometer-sized electrodes showed well-defined sigmoidal curves and stable diffusion-limited responses with cyclic voltammetry. The pencil-shaped optical fiber, which has a conical tip with a cone angle of 20 degrees , was effective for controlling the electrode radius. The pencil-shaped electrodes had higher reproducibility and smaller electrode radii (r(app) etched optical fiber electrodes. By using a pencil-shaped electrode with a 105-nm radius as a probe, we obtained simultaneous electrochemical and optical images of an implantable interdigitated array electrode. We achieved nanometer-scale resolution with a combination of scanning electrochemical microscopy SECM and optical microscopy. The resolution of the electrochemical and optical images indicated sizes of 300 and 930 nm, respectively. The neurites of living PC12 cells were also successfully imaged on a 1.6-microm scale by using the negative feedback mode of an SECM.

  17. Endoscopic case

    Directory of Open Access Journals (Sweden)

    Fernando Pereira

    2017-01-01

    Full Text Available We present the case of a ten-year-old female patient referred to Gastroenterolgy consultation for abdominal pain and cramping, usually worse after eating, recurring diarrhoea, hypochromic and microcytic anaemia with low serum iron and ferritin levels. Moderate to severe Crohn’s disease of the terminal ileum e right colon (L3 was diagnosed, based on endoscopic image and biopsy. The patient was treated with prednisone and azathioprine, but after one year of treatment she was steroids dependent and treatment was switched to infliximab. One year after beginning this treatment, the patient achieved remission (clinical and laboratorial parameters. A control colonoscopy showed mucosal healing with scars and deformation with stenosis of ileocecal valve (Figures 1-2. Surgical intervention will be probably necessary in near future.

  18. Endoscopic ampullectomy

    Directory of Open Access Journals (Sweden)

    Michael Bourke

    2012-01-01

    Full Text Available Endoscopic ampullectomy offers a minimally invasive method of effectively treating non-invasive neoplasms of the ampulla of Vater and surrounding peri-ampullary region with high success and relative safety. These lesions would otherwise require surgical intervention, including pancreatico-duodenectomy. However, major complications may occur and a careful assessment of the patients comorbidities and their ability to tolerate adverse events needs to be factored into the treatment decision. Careful staging, often multi-modality is required, particularly for extensive lesions. Complete en-bloc excision of the entire neoplasm should be the goal with conventional papillary adenomas. Large lesions with extra-papillary extension currently require extended piecemeal excision, however with meticulous technique, recurrence is uncommon in longterm follow up.

  19. Shear force distance control in a scanning near-field optical microscope: in resonance excitation of the fiber probe versus out of resonance excitation

    International Nuclear Information System (INIS)

    Lapshin, D.A.; Letokhov, V.S.; Shubeita, G.T.; Sekatskii, S.K.; Dietler, G.

    2004-01-01

    The experimental results of the direct measurement of the absolute value of interaction force between the fiber probe of a scanning near-field optical microscope (SNOM) operated in shear force mode and a sample, which were performed using combined SNOM-atomic force microscope setup, are discussed for the out-of-resonance fiber probe excitation mode. We demonstrate that the value of the tapping component of the total force for this mode at typical dither amplitudes is of the order of 10 nN and thus is quite comparable with the value of this force for in resonance fiber probe excitation mode. It is also shown that for all modes this force component is essentially smaller than the usually neglected static attraction force, which is of the order of 200 nN. The true contact nature of the tip-sample interaction during the out of resonance mode is proven. From this, we conclude that such a detection mode is very promising for operation in liquids, where other modes encounter great difficulties

  20. Endoscopic root canal treatment.

    Science.gov (United States)

    Moshonov, Joshua; Michaeli, Eli; Nahlieli, Oded

    2009-10-01

    To describe an innovative endoscopic technique for root canal treatment. Root canal treatment was performed on 12 patients (15 teeth), using a newly developed endoscope (Sialotechnology), which combines an endoscope, irrigation, and a surgical microinstrument channel. Endoscopic root canal treatment of all 15 teeth was successful with complete resolution of all symptoms (6-month follow-up). The novel endoscope used in this study accurately identified all microstructures and simplified root canal treatment. The endoscope may be considered for use not only for preoperative observation and diagnosis but also for active endodontic treatment.

  1. Identification of nodal tissue in the living heart using rapid scanning fiber-optics confocal microscopy and extracellular fluorophores.

    Science.gov (United States)

    Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

    2013-09-01

    Risks associated with pediatric reconstructive heart surgery include injury of the sinoatrial node (SAN) and atrioventricular node (AVN), requiring cardiac rhythm management using implantable pacemakers. These injuries are the result of difficulties in identifying nodal tissues intraoperatively. Here we describe an approach based on confocal microscopy and extracellular fluorophores to quantify tissue microstructure and identify nodal tissue. Using conventional 3-dimensional confocal microscopy we investigated the microstructural arrangement of SAN, AVN, and atrial working myocardium (AWM) in fixed rat heart. AWM exhibited a regular striated arrangement of the extracellular space. In contrast, SAN and AVN had an irregular, reticulated arrangement. AWM, SAN, and AVN tissues were beneath a thin surface layer of tissue that did not obstruct confocal microscopic imaging. Subsequently, we imaged tissues in living rat hearts with real-time fiber-optics confocal microscopy. Fiber-optics confocal microscopy images resembled images acquired with conventional confocal microscopy. We investigated spatial regularity of tissue microstructure from Fourier analysis and second-order image moments. Fourier analysis of fiber-optics confocal microscopy images showed that the spatial regularity of AWM was greater than that of nodal tissues (37.5 ± 5.0% versus 24.3 ± 3.9% for SAN and 23.8 ± 3.7% for AVN; Pfiber-optics confocal microscopy. Application of the approach in pediatric reconstructive heart surgery may reduce risks of injuring nodal tissues.

  2. Equivalente esférico e valores da espessura da camada de fibras nervosas obtidas com o GDX TM Scanning Laser System® Spherical equivalent and nerve fiber layer thickness assessed with GDX TM Scanning Laser System®

    Directory of Open Access Journals (Sweden)

    Lênio Souza Alvarenga

    1999-12-01

    Full Text Available Objetivo: Estudar a influência do equivalente esférico nos valores obtidos pelo GDX TM Scanning Laser System®. Métodos: Foram avaliados 41 olhos de 41 voluntários sem doenças oculares e com campo visual sem alterações. Foi realizada a polarimetria de varredura a laser com o GDX TM Scanning Laser System® de acordo com as instruções contidas no manual do aparelho. Foram comparados os valores obtidos nesse exame em um grupo de pacientes com equivalente esférico positivo e em um outro com este valor nulo ou negativo, pelo teste de Mann-Whitney. Resultados: Não se verificou diferença estatística entre os valores obtidos nos olhos de pacientes do grupo I e os do grupo II. Não foi encontrada correlação entre o equivalente esférico e os valores obtidos com o GDX TM Scanning Laser System®. Conclusões: Na amostra estudada não houve diferença estatística entre os valores obtidos em um grupo de olhos com equivalente esférico positivo e outro com este valor negativo ou nulo, usando-se o GDX TM Scanning Laser System®.Purpose: To evaluate the effect of spherical equivalent on the acquisition of nerve fiber layer (NFL thickness with GDX TM Scanning Laser System®. Methods: Forty-one eyes of 41 volunteers were enrolled in this study. All of them presented with no ocular disease and no visual field defect. The NFL thickness was measured with GDX TM Scanning Laser System® as described in its manual. The values obtained in a group of volunteers with negative spherical equivalent (group I were compared to those from a group with a positive spherical equivalent (group II by the Mann-Whitney test. Results: There was no statistical difference between mea-surements in eyes of group I and those in group II. The NFL thickness measurements were not correlated with the sphe-rical equivalent. Conclusions: In the studied group there was no statistical difference in the GDX TM Scanning Laser System® parameters related to spherical equivalent.

  3. Cycloid scanning for wide field optical coherence tomography endomicroscopy and angiography in vivo

    Science.gov (United States)

    Liang, Kaicheng; Wang, Zhao; Ahsen, Osman O.; Lee, Hsiang-Chieh; Potsaid, Benjamin M.; Jayaraman, Vijaysekhar; Cable, Alex; Mashimo, Hiroshi; Li, Xingde; Fujimoto, James G.

    2018-01-01

    Devices that perform wide field-of-view (FOV) precision optical scanning are important for endoscopic assessment and diagnosis of luminal organ disease such as in gastroenterology. Optical scanning for in vivo endoscopic imaging has traditionally relied on one or more proximal mechanical actuators, limiting scan accuracy and imaging speed. There is a need for rapid and precise two-dimensional (2D) microscanning technologies to enable the translation of benchtop scanning microscopies to in vivo endoscopic imaging. We demonstrate a new cycloid scanner in a tethered capsule for ultrahigh speed, side-viewing optical coherence tomography (OCT) endomicroscopy in vivo. The cycloid capsule incorporates two scanners: a piezoelectrically actuated resonant fiber scanner to perform a precision, small FOV, fast scan and a micromotor scanner to perform a wide FOV, slow scan. Together these scanners distally scan the beam circumferentially in a 2D cycloid pattern, generating an unwrapped 1 mm × 38 mm strip FOV. Sequential strip volumes can be acquired with proximal pullback to image centimeter-long regions. Using ultrahigh speed 1.3 μm wavelength swept-source OCT at a 1.17 MHz axial scan rate, we imaged the human rectum at 3 volumes/s. Each OCT strip volume had 166 × 2322 axial scans with 8.5 μm axial and 30 μm transverse resolution. We further demonstrate OCT angiography at 0.5 volumes/s, producing volumetric images of vasculature. In addition to OCT applications, cycloid scanning promises to enable precision 2D optical scanning for other imaging modalities, including fluorescence confocal and nonlinear microscopy. PMID:29682598

  4. Current Status of Peroral Endoscopic Myotomy.

    Science.gov (United States)

    Cho, Young Kwan; Kim, Seong Hwan

    2018-01-01

    Peroral endoscopic myotomy (POEM) has been established as an optional treatment for achalasia. POEM is an endoluminal procedure that involves dissection of esophageal muscle fibers followed by submucosal tunneling. Inoue first attempted to use POEM for the treatment of achalasia in humans. Expanded indications of POEM include classic indications such as type I, type II, type III achalasia, failed prior treatments, including Botulinum toxin injection, endoscopic balloon dilation, laparoscopic Heller myotomy, and hypertensive motor disorders such as diffuse esophageal spasm, jackhammer esophagus. Contraindications include prior radiation therapy to the esophagus and prior extensive esophageal mucosal resection/ablation involving the POEM field. Most of the complications are minor and self-limited and can be managed conservatively. As POEM emerged as the main treatment for achalasia, various adaptations to tunnel endoscopic surgery have been attempted. Tunnel endoscopic surgery includes POEM, peroral endoscopic tumor resection, gastric peroral endoscopic pyloromyotomy. POEM has been widely accepted as a treatment for all types of achalasia, even for specific cases such as achalasia with failed prior treatments, and hypertensive motor disorders.

  5. Current Status of Peroral Endoscopic Myotomy

    Science.gov (United States)

    Cho, Young Kwan; Kim, Seong Hwan

    2018-01-01

    Peroral endoscopic myotomy (POEM) has been established as an optional treatment for achalasia. POEM is an endoluminal procedure that involves dissection of esophageal muscle fibers followed by submucosal tunneling. Inoue first attempted to use POEM for the treatment of achalasia in humans. Expanded indications of POEM include classic indications such as type I, type II, type III achalasia, failed prior treatments, including Botulinum toxin injection, endoscopic balloon dilation, laparoscopic Heller myotomy, and hypertensive motor disorders such as diffuse esophageal spasm, jackhammer esophagus. Contraindications include prior radiation therapy to the esophagus and prior extensive esophageal mucosal resection/ablation involving the POEM field. Most of the complications are minor and self-limited and can be managed conservatively. As POEM emerged as the main treatment for achalasia, various adaptations to tunnel endoscopic surgery have been attempted. Tunnel endoscopic surgery includes POEM, peroral endoscopic tumor resection, gastric peroral endoscopic pyloromyotomy. POEM has been widely accepted as a treatment for all types of achalasia, even for specific cases such as achalasia with failed prior treatments, and hypertensive motor disorders. PMID:29397656

  6. Current Status of Peroral Endoscopic Myotomy

    Directory of Open Access Journals (Sweden)

    Young Kwan Cho

    2018-01-01

    Full Text Available Peroral endoscopic myotomy (POEM has been established as an optional treatment for achalasia. POEM is an endoluminal procedure that involves dissection of esophageal muscle fibers followed by submucosal tunneling. Inoue first attempted to use POEM for the treatment of achalasia in humans. Expanded indications of POEM include classic indications such as type I, type II, type III achalasia, failed prior treatments, including Botulinum toxin injection, endoscopic balloon dilation, laparoscopic Heller myotomy, and hypertensive motor disorders such as diffuse esophageal spasm, jackhammer esophagus. Contraindications include prior radiation therapy to the esophagus and prior extensive esophageal mucosal resection/ablation involving the POEM field. Most of the complications are minor and self-limited and can be managed conservatively. As POEM emerged as the main treatment for achalasia, various adaptations to tunnel endoscopic surgery have been attempted. Tunnel endoscopic surgery includes POEM, peroral endoscopic tumor resection, gastric peroral endoscopic pyloromyotomy. POEM has been widely accepted as a treatment for all types of achalasia, even for specific cases such as achalasia with failed prior treatments, and hypertensive motor disorders.

  7. Micromotor endoscope catheter for in vivo, ultrahigh-resolution optical coherence tomography

    Science.gov (United States)

    Herz, P. R.; Chen, Y.; Aguirre, A. D.; Schneider, K.; Hsiung, P.; Fujimoto, J. G.; Madden, K.; Schmitt, J.; Goodnow, J.; Petersen, C.

    2004-10-01

    A distally actuated, rotational-scanning micromotor endoscope catheter probe is demonstrated for ultrahigh-resolution in vivo endoscopic optical coherence tomography (OCT) imaging. The probe permits focus adjustment for visualization of tissue morphology at varying depths with improved transverse resolution compared with standard OCT imaging probes. The distal actuation avoids nonuniform scanning motion artifacts that are present with other probe designs and can permit a wider range of imaging speeds. Ultrahigh-resolution endoscopic imaging is demonstrated in a rabbit with micromotor endoscope catheter probe promises to improve OCT imaging performance in future endoscopic imaging applications.

  8. Growth and decay dynamics of a stable microbubble produced at the end of a near-field scanning optical microscopy fiber probe

    International Nuclear Information System (INIS)

    Taylor, R.S.; Hnatovsky, C.

    2004-01-01

    Low power cw laser radiation coupled into a near-field scanning optical microscopy fiber probe has been used to generate a stable microbubble in water. A probe tip which was selectively chemically etched and metallized served as a microheater for the generation of the stable bubble. Bubble diameters in the range of 40-400 μm and lifetimes of over an hour have been obtained. The microbubble exhibited a linear growth phase over a period of a few seconds before reaching a maximum diameter which depended on the laser power. When the laser beam was blocked the microbubble decayed with a rate which was inversely proportional to the bubble diameter. The bubble lifetime depended on the square of the initial bubble diameter. Instabilities which transform a large stable bubble into a microjet stream of micron sized bubbles as the laser power was increased is also described

  9. Mechanisms of biliary stent clogging: confocal laser scanning and scanning electron microscopy.

    Science.gov (United States)

    van Berkel, A M; van Marle, J; Groen, A K; Bruno, M J

    2005-08-01

    Endoscopic insertion of plastic biliary endoprostheses is a well-established treatment for obstructive jaundice. The major limitation of this technique is late stent occlusion. In order to compare events involved in biliary stent clogging and identify the distribution of bacteria in unblocked stents, confocal laser scanning (CLS) and scanning electron microscopy (SEM) were carried out on two different stent materials - polyethylene (PE) and hydrophilic polymer-coated polyurethane (HCPC). Ten consecutive patients with postoperative benign biliary strictures were included in the study. Two 10-Fr stents 9 cm in length, one made of PE and the other of HCPC, were inserted. The stents were electively exchanged after 3 months and examined using CLS and SEM. No differences were seen between the two types of stent. The inner stent surface was covered with a uniform amorphous layer. On top of this layer, a biofilm of living and dead bacteria was found, which in most cases was unstructured. The lumen was filled with free-floating colonies of bacteria and crystals, surrounded by mobile laminar structures of mucus. An open network of large dietary fibers was seen in all of the stents. The same clogging events occurred in both PE and HCPC stents. The most remarkable observation was the identification of networks of large dietary fibers, resulting from duodenal reflux, acting as a filter. The build-up of this intraluminal framework of dietary fibers appears to be a major factor contributing to the multifactorial process of stent clogging.

  10. 10-channel fiber array fabrication technique for parallel optical coherence tomography system

    Science.gov (United States)

    Arauz, Lina J.; Luo, Yuan; Castillo, Jose E.; Kostuk, Raymond K.; Barton, Jennifer

    2007-02-01

    Optical Coherence Tomography (OCT) shows great promise for low intrusive biomedical imaging applications. A parallel OCT system is a novel technique that replaces mechanical transverse scanning with electronic scanning. This will reduce the time required to acquire image data. In this system an array of small diameter fibers is required to obtain an image in the transverse direction. Each fiber in the array is configured in an interferometer and is used to image one pixel in the transverse direction. In this paper we describe a technique to package 15μm diameter fibers on a siliconsilica substrate to be used in a 2mm endoscopic probe tip. Single mode fibers are etched to reduce the cladding diameter from 125μm to 15μm. Etched fibers are placed into a 4mm by 150μm trench in a silicon-silica substrate and secured with UV glue. Active alignment was used to simplify the lay out of the fibers and minimize unwanted horizontal displacement of the fibers. A 10-channel fiber array was built, tested and later incorporated into a parallel optical coherence system. This paper describes the packaging, testing, and operation of the array in a parallel OCT system.

  11. Endoscopic submucosal dissection

    DEFF Research Database (Denmark)

    Pimentel-Nunes, Pedro; Dinis-Ribeiro, Mário; Ponchon, Thierry

    2015-01-01

    evidence). 2 ESGE recommends endoscopic resection with a curative intent for visible lesions in Barrett's esophagus (strong recommendation, moderate quality evidence). ESD has not been shown to be superior to EMR for excision of mucosal cancer, and for that reason EMR should be preferred. ESD may...... RECOMMENDATIONS: 1 ESGE recommends endoscopic en bloc resection for superficial esophageal squamous cell cancers (SCCs), excluding those with obvious submucosal involvement (strong recommendation, moderate quality evidence). Endoscopic mucosal resection (EMR) may be considered in such lesions when...

  12. Retinal nerve fiber layer in primary open-angle glaucoma with high myopia determined by optical coherence tomography and scanning laser polarimetry.

    Science.gov (United States)

    Wang, Xiao-en; Wang, Xiao-yu; Gu, Yang-shun; Huang, Zhu

    2013-01-01

    Fundus changes associated with high myopia (HM) may mask those associated with primary open-angle glaucoma (POAG). This study aim to determine the characteristics of RNFL thickness changes in patients with both POAG and HM and compare these to changes in patients with only HM. The diagnostic capabilities of both OCT and GDxVCC in this subset of patients are also evaluated. Twenty-two eyes with POAG and HM (spherical equivalent (SE) between -6.0 and -12.0 D) were evaluated, and 22 eyes with HM were used for comparison. Characteristic retinal nerve fiber layer (RNFL) thickness profiles in patients with POAG and HM were examined using optical coherence tomography (OCT) and scanning laser polarimetry with variable corneal compensation (GDxVCC), and the diagnostic capabilities of these imaging modalities were compared. RNFL parameters evaluated included superior average (Savg-GDx), inferior average (Iavg-GDx), temporal-superior-nasal- inferior-temporal (TSNIT) average, and nerve fiber indicator (NFI) on GDxVCC and superior average (Savg-OCT), inferior average (Iavg-OCT), nasal average (Navg-OCT), temporal average (Tavg-OCT), and average thickness (AvgThick-OCT) on OCT (fast RNFL scan). Visual field testing was performed and defects were evaluated using mean defect (MD) and pattern standard deviation (PSD). The RNFL parameters (P < 0.05) significantly different between groups included Savg-GDx, Iavg-GDx, TSNIT average, NFI, Savg-OCT, Iavg-OCT, Tavg-OCT, and AvgThick-OCT. Significant correlations existed between TSNIT average and AvgThick-OCT (r = 0.778), TSNIT average and MD (r = 0.749), AvgThick-OCT and MD (r = 0.647), TSNIT average and PSD (r = -0.756), and AvgThick-OCT and PSD (r = -0.784). The area under the receiver operating characteristic curve (AUROC) values of TSNIT average, Savg-GDx, Iavg-GDx, NFI, Savg-OCT, Iavg-OCT, Navg-OCT, Tavg-OCT, and AvgThick-OCT were 0.947, 0.962, 0.973, 0.994, 0.909, 0.917, 0.511, 0.906, and 0.913, respectively. The NFI AUROC was the

  13. Changes in Macular Retinal Layers and Peripapillary Nerve Fiber Layer Thickness after 577-nm Pattern Scanning Laser in Patients with Diabetic Retinopathy.

    Science.gov (United States)

    Shin, Ji Soo; Lee, Young Hoon

    2017-12-01

    The aim of this study was to evaluate the changes in thickness of each macular retinal layer, the peripapillary retinal nerve fiber layer (RNFL), and central macular thickness (CMT) after 577-nm pattern scanning laser (PASCAL) photocoagulation in patients with diabetic retinopathy. This retrospective study included 33 eyes with diabetic retinopathy that underwent 577-nm PASCAL photocoagulation. Each retinal layer thickness, peripapillary RNFL thickness, and CMT were measured by spectral-domain optical coherence tomography before 577-nm PASCAL photocoagulation, as well as at 1, 6, and 12 months after 577-nm PASCAL photocoagulation. Computerized intraretinal segmentation of optical coherence tomography was performed to identify the thickness of each retinal layer. The average thickness of the RNFL, ganglion cell layer, inner plexiform layer, inner nuclear layer, inner retinal layer, and CMT at each follow-up increased significantly from baseline (p 0.05). Each macular retinal layer and CMT had a tendency to increase for one year after 577-nm PASCAL photocoagulation, whereas the average thickness of retinal pigment epithelium decreased at one-year follow-up compared to the baseline. Although an increase in peripapillary RNFL thickness was observed one month after 577-nm PASCAL photocoagulation, there were no significant changes at the one-year follow-up compared to the baseline. © 2017 The Korean Ophthalmological Society

  14. Endoscopic Devices for Obesity.

    Science.gov (United States)

    Sampath, Kartik; Dinani, Amreen M; Rothstein, Richard I

    2016-06-01

    The obesity epidemic, recognized by the World Health Organization in 1997, refers to the rising incidence of obesity worldwide. Lifestyle modification and pharmacotherapy are often ineffective long-term solutions; bariatric surgery remains the gold standard for long-term obesity weight loss. Despite the reported benefits, it has been estimated that only 1% of obese patients will undergo surgery. Endoscopic treatment for obesity represents a potential cost-effective, accessible, minimally invasive procedure that can function as a bridge or alternative intervention to bariatric surgery. We review the current endoscopic bariatric devices including space occupying devices, endoscopic gastroplasty, aspiration technology, post-bariatric surgery endoscopic revision, and obesity-related NOTES procedures. Given the diverse devices already FDA approved and in development, we discuss the future directions of endoscopic therapies for obesity.

  15. Measurement of retinal nerve fiber layer thickness in eyes with optic disc swelling by using scanning laser polarimetry and optical coherence tomography.

    Science.gov (United States)

    Hata, Masayuki; Miyamoto, Kazuaki; Oishi, Akio; Kimura, Yugo; Nakagawa, Satoko; Horii, Takahiro; Yoshimura, Nagahisa

    2014-01-01

    The retinal nerve fiber layer thickness (RNFLT) in patients with optic disc swelling of different etiologies was compared using scanning laser polarimetry (SLP) and spectral-domain optical coherence tomography (OCT). Forty-seven patients with optic disc swelling participated in the cross-sectional study. Both GDx SLP (enhanced corneal compensation) and Spectralis spectral-domain OCT measurements of RNFLT were made in 19 eyes with papilledema (PE), ten eyes with optic neuritis (ON), and 18 eyes with nonarteritic anterior ischemic optic neuropathy (NAION) at the neuro-ophthalmology clinic at Kyoto University Hospital. Differences in SLP (SLP-RNFLT) and OCT (OCT-RNFLT) measurements among different etiologies were investigated. No statistical differences in average OCT-RNFLT among PE, ON, and NAION patients were noted. Average SLP-RNFLT in NAION patients was smaller than in PE (P<0.01) or ON (P=0.02) patients. When RNFLT in each retinal quadrant was compared, no difference among etiologies was noted on OCT, but on SLP, the superior quadrant was thinner in NAION than in PE (P<0.001) or ON (P=0.001) patients. Compared with age-adjusted normative data of SLP-RNFLT, average SLP-RNFLT in PE (P<0.01) and ON (P<0.01) patients was greater. Superior SLP-RNFLT in NAION patients was smaller (P=0.026). The ratio of average SLP-RNFLT to average OCT-RNFLT was smaller in NAION than in PE (P=0.001) patients. In the setting of RNFL thickening, despite increased light retardance in PE and ON eyes, SLP revealed that NAION eyes have less retardance, possibly associated with ischemic axonal loss.

  16. Endoscopic sensing of alveolar pH.

    Science.gov (United States)

    Choudhury, D; Tanner, M G; McAughtrie, S; Yu, F; Mills, B; Choudhary, T R; Seth, S; Craven, T H; Stone, J M; Mati, I K; Campbell, C J; Bradley, M; Williams, C K I; Dhaliwal, K; Birks, T A; Thomson, R R

    2017-01-01

    Previously unobtainable measurements of alveolar pH were obtained using an endoscope-deployable optrode. The pH sensing was achieved using functionalized gold nanoshell sensors and surface enhanced Raman spectroscopy (SERS). The optrode consisted of an asymmetric dual-core optical fiber designed for spatially separating the optical pump delivery and signal collection, in order to circumvent the unwanted Raman signal generated within the fiber. Using this approach, we demonstrate a ~100-fold increase in SERS signal-to-fiber background ratio, and demonstrate multiple site pH sensing with a measurement accuracy of ± 0.07 pH units in the respiratory acini of an ex vivo ovine lung model. We also demonstrate that alveolar pH changes in response to ventilation.

  17. Endoscopic Treatment of Intrasheath Peroneal Tendon Subluxation

    Directory of Open Access Journals (Sweden)

    Frederick Michels

    2013-01-01

    Full Text Available Intrasheath subluxation of the peroneal tendons within the peroneal groove is an uncommon problem. Open exploration combined with a peroneal groove-deepening procedure and retinacular reefing is the recommended treatment. This extensive lateral approach needs incision of the intact superior peroneal retinaculum and repair afterwards. We treated three patients with a painful intrasheath subluxation using an endoscopic approach. During this tendoscopy both tendons were inspected. The distal muscle fibers of the peroneus brevis tendon were resected in two patients. A partial tear was debrided in the third patient. All patients had a good result. No wound-healing problems or other complications occurred. Early return to work and sports was possible. An endoscopic approach was successful in treatment of an intrasheath subluxation of the peroneal tendons.

  18. Learning endoscopic resection in the esophagus

    NARCIS (Netherlands)

    van Vilsteren, Frederike G. I.; Pouw, Roos E.; Herrero, Lorenza Alvarez; Bisschops, Raf; Houben, Martin; Peters, Frans T. M.; Schenk, B. E.; Weusten, Bas L. A. M.; Schoon, Erik J.; Bergman, Jacques J. G. H. M.

    Background: Endoscopic resection is the cornerstone of endoscopic management of esophageal early neoplasia. However, endoscopic resection is a complex technique requiring knowledge and expertise. Our aims were to identify the most important learning points in performing endoscopic resection in a

  19. High numerical aperture imaging by using multimode fibers with micro-fabricated optics

    KAUST Repository

    Bianchi, Silvio; Rajamanickam, V.; Ferrara, Lorenzo; Di Fabrizio, Enzo M.; Di Leonardo, Roberto; Liberale, Carlo

    2014-01-01

    Controlling light propagation into multimode optical fibers through spatial light modulators provides highly miniaturized endoscopes and optical micromanipulation probes. We increase the numerical aperture up to nearly 1 by micro-optics fabricated on the fiber-end.

  20. Endoscopic Surgery for Traumatic Acute Subdural Hematoma

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kon

    2014-01-01

    Full Text Available Traumatic acute subdural hematoma (ASDH is generally addressed by craniotomy under general anesthesia. We report a patient whose traumatic ASDH was treated under local anesthesia by one-burr-hole endoscopic surgery. This 87-year-old woman had undergone coil embolization for a ruptured right middle-cerebral artery aneurysm and placement of a ventriculoperitoneal shunt for normal pressure hydrocephalus 5 years earlier. Upon admission, she manifested consciousness disturbance after suffering head trauma and right hemiplegia. Her Glasgow Coma Scale score was 8 (E2V2M4. Computed tomography (CT demonstrated a thick, left-frontotemporal ASDH. Due to her advanced age and poor condition, we performed endoscopic surgery rather than craniotomy to evacuate the ASDH. Under local anesthesia, we made a burr hole in her left forehead and increased its size to 15 mm in diameter. After introducing a transparent sheath into the hematoma cavity with a rigid endoscope, the clot was evacuated with a suction tube. The arterial bleeding point was electrically coagulated. A postoperative CT scan confirmed the reduction of the hematoma. There was neither brain compression nor brain swelling. Her consciousness disturbance and right hemiplegia improved immediately. Endoscopic surgery may represent a viable method to address traumatic intracranial hematomas in some patients.

  1. Mitigating fluorescence spectral overlap in wide-field endoscopic imaging

    Science.gov (United States)

    Hou, Vivian; Nelson, Leonard Y.; Seibel, Eric J.

    2013-01-01

    Abstract. The number of molecular species suitable for multispectral fluorescence imaging is limited due to the overlap of the emission spectra of indicator fluorophores, e.g., dyes and nanoparticles. To remove fluorophore emission cross-talk in wide-field multispectral fluorescence molecular imaging, we evaluate three different solutions: (1) image stitching, (2) concurrent imaging with cross-talk ratio subtraction algorithm, and (3) frame-sequential imaging. A phantom with fluorophore emission cross-talk is fabricated, and a 1.2-mm ultrathin scanning fiber endoscope (SFE) is used to test and compare these approaches. Results show that fluorophore emission cross-talk could be successfully avoided or significantly reduced. Near term, the concurrent imaging method of wide-field multispectral fluorescence SFE is viable for early stage cancer detection and localization in vivo. Furthermore, a means to enhance exogenous fluorescence target-to-background ratio by the reduction of tissue autofluorescence background is demonstrated. PMID:23966226

  2. New endoscope shaft for endoscopic transsphenoidal pituitary surgery.

    NARCIS (Netherlands)

    Lindert, E.J. van; Grotenhuis, J.A.

    2005-01-01

    OBJECTIVE: To describe a new endoscope shaft developed for suction-aspiration during endoscopic transsphenoidal pituitary surgery. METHODS: A custom-made shaft for a Wolf endoscope (Richard Wolf GmbH, Knittlingen, Germany) was developed with a height of 10 mm and a width of 5 mm, allowing an

  3. [Endoscopic extraction of gallbladder calculi].

    Science.gov (United States)

    Kühner, W; Frimberger, E; Ottenjann, R

    1984-06-29

    Endoscopic extraction of gallbladder stones were performed, as far as we know for the first time, in three patients with combined choledochocystolithiasis. Following endoscopic papillotomy (EPT) and subsequent mechanical lithotripsy of multiple choledochal concrements measuring up to 3 cm the gallbladder stones were successfully extracted with a Dormia basket through the cystic duct. The patients have remained free of complications after the endoscopic intervention.

  4. New flexible endoscope for otologic application

    Science.gov (United States)

    Marchan, Mark L.

    1993-07-01

    Endoscopy has become an important procedure in many medical specialties. For the Otologist, however, space limitations within the ear have restricted development of endoscopic procedures. The desire for minimally invasive techniques in Otology has demonstrated itself through the work of numerous physicians who have performed procedures ranging from diagnostic inspection of the middle ear to viewing the interior of the cochlea. To assist in performing such endoscopic procedures, Xomed-Treace has developed a line of flexible fiberoptic endoscopes for use by the Otologist. These scopes combine illumination and imaging fiber bundles within a small diameter unit ranging in size from 0.8 mm to 1.2 mm. The 1.2 mm scope is produced with an angled, rigid stainless steel sheath. The 0.8 mm scope is flexible with the ability to articulate 120 degree(s) in one direction. The fiberscopes have been designed for the Otologist to produce a good resolution image while allowing ease of operation through ergonomics and consideration of the surgical anatomy.

  5. Endoscopic management of colorectal adenomas.

    Science.gov (United States)

    Meier, Benjamin; Caca, Karel; Fischer, Andreas; Schmidt, Arthur

    2017-01-01

    Colorectal adenomas are well known precursors of invasive adenocarcinoma. Colonoscopy is the gold standard for adenoma detection. Colonoscopy is far more than a diagnostic tool, as it allows effective treatment of colorectal adenomas. Endoscopic resection of colorectal adenomas has been shown to reduce the incidence and mortality of colorectal cancer. Difficult resection techniques are available, such as endoscopic mucosal resection, endoscopic submucosal dissection and endoscopic full-thickness resection. This review aims to provide an overview of the different endoscopic resection techniques and their indications, and summarizes the current recommendations in the recently published guideline of the European Society of Gastrointestinal Endoscopy.

  6. Endoscope-guided pneumatic dilation for treatment of esophageal achalasia

    Science.gov (United States)

    Chuah, Seng-Kee; Wu, Keng-Liang; Hu, Tsung-Hui; Tai, Wei-Chen; Changchien, Chi-Sin

    2010-01-01

    Pneumatic dilation (PD) is considered to be the first line nonsurgical therapy for achalasia. The principle of the procedure is to weaken the lower esophageal sphincter by tearing its muscle fibers by generating radial force. The endoscope-guided procedure is done without fluoroscopic control. Clinicians usually use a low-compliance balloon such as Rigiflex dilator to perform endoscope-guided PD for the treatment of esophageal achalasia. It has the advantage of determining mucosal injury during the dilation process, so that a repeat endoscopy is not needed to assess the mucosal tearing. Previous studies have shown that endoscope-guided PD is an efficient and safe nonsurgical therapy with results that compare well with other treatment modalities. Although the results may be promising, long-term follow-up is required in the near future. PMID:20101764

  7. Bilateral endoscopic endonasal marsupialization of nasopalatine duct cyst

    Directory of Open Access Journals (Sweden)

    Yohei Honkura

    2015-02-01

    Full Text Available Nasopalatine duct cysts are the most common non-odontogenic cysts in the maxilla, and are conventionally treated through a sublabial or palatine approach. Recently, the endoscopic approach has been used, but experience is extremely limited. We treated a 29-year-old male with nasopalatine duct cyst by endoscopic marsupialization, but paresthesia of the incisor region occurred after surgery. This paresthesia gradually remitted within 6 months. The nasopalatine nerve, which innervates the upper incisor region, enters two lateral canals separately at the nasal floor and exits the central main canal at the palate. Damage to the bilateral nasopalatine nerves might lead to paresthesia, so we recommend careful examination for nerve fibers during endoscopic surgery, especially if fenestration is performed on both sides.

  8. Outcomes following Purely Endoscopic Endonasal Resection of Pituitary adenomas

    Directory of Open Access Journals (Sweden)

    Rezaul Amin

    2013-01-01

    Full Text Available Background: The use of endoscope for the management of pituitary adenoma is not new. The better magnification and illumination provided by the endoscope gives better outcome than microscopic pituitary surgery. Objective: To find out the benefits of endoscope in relation to microscopic surgery. Materials and Methods: We performed 45 cases of pituitary adenoma surgery by endoscopic endonasal approach from July 2008 to July 2010. Results: Forty five cases underwent endoscopic transsphenoidal approach. Gross total removal was done in 35 cases and subtotal removal was done in 10 cases. Residual tumours were seen in 10 cases (22% in postoperative follow-up MRI scan. Visual improvement was satisfactory, and hormonal improvement of functional adenoma was nice. Postoperative visual acuity and visual field were improved in 75% cases. There were 37% cases of temporary diabetes insipidus and about 4.5% cases of permanent diabetes insipidus. The average duration of follow-up was 20 months. One patient required reexploration to correct visual deterioration in the immediate postoperative period. There were 4.5% cases of CSF leak and 6.6% mortality. Mortality was due to electrolyte imbalance and improper management of infection and hydrocephalus. Conclusion: Endoscopic endonasal pituitary surgery now has become a gold standard surgery for most of the pituitary adenomas because of its better advantages in relation to microscopic surgery and less complications and less hospital stay.

  9. Endoscopic anatomy of the orbital floor and maxillary sinus.

    Science.gov (United States)

    Moore, Corey C; Bromwich, Matthew; Roth, Kathy; Matic, Damir B

    2008-01-01

    Endoscopic repair of orbital blow-out fractures could become a predictable and efficient treatment alternative to traditional methods. However, maxillary sinus endoscopy provides a complex and disorienting view of the orbital floor. To be a useful and consistent technique for providing access to the orbital floor, specific knowledge of maxillary endoscopic anatomy is required. The purpose of the study was to provide an anatomic description of the orbital floor via the endoscopic approach. Objectives include defining consistent landmarks for use in endoscopic repair of orbital floor fractures. Using 0- and 30-degree rigid endoscopes, 6 fresh cadavers (12 maxillary sinuses) were examined via a standard Caldwell-Luc approach. Computed tomographic scans, plastic molds, and digital images were used to compare observable averages within bony anatomy. Potential bony landmarks were correlated with soft-tissue anatomy in fresh specimens. The maxillary ostium, orbital floor, and lateral ethmoid air cells were visualized, and their structures were described. Observations were made in relation to the anatomy of the orbital floor and maxillary sinus, including fracture pattern and force transmission pathways. An "orbitomaxillary" sinus bony thickening was identified and described for the first time. This study provides the basis for further refinement of surgical technique and opens the door for future clinical trials using endoscopic repair.

  10. [Endoscopic sclerotherapy in the combined treatment of portal hypertension in children].

    Science.gov (United States)

    Ul'rikh, E V; Korolev, M P; Kupatadze, F D; Sevriugov, B L; Nabokov, V V

    1992-01-01

    The authors have performed 28 sessions of endoscopic sclerotherapy of dilated esophagus veins in children. The 70% ethyl alcohol was used. Six sessions were carried out in patients with gastroesophageal hemorrhage. In 22 patients the sclerotherapy was carried on according to plan. The fiber gastroscope with a standard injector was used. A conclusion is made of expediency of using endoscopic sclerotherapy in complex treatment of portal hypertension in children.

  11. Transaxillary Endoscopic Breast Augmentation

    Directory of Open Access Journals (Sweden)

    Hyung-Bo Sim

    2014-09-01

    Full Text Available The axillary technique is the most popular approach to breast augmentation among Korean women. Transaxillary breast augmentation is now conducted with sharp electrocautery dissection under direct endoscopic vision throughout the entire process. The aims of this method are clear: both a bloodless pocket and a sharp non-traumatic dissection. Round textured or anatomical cohesive gel implants have been used to make predictable well-defined inframammary creases because textured surface implants demonstrated a better stability attributable to tissue adherence compared with smooth surface implants. The axillary endoscopic technique has greatly evolved, and now the surgical results are comparable to those with the inframammary approach. The author feels that this technique is an excellent choice for young patients with an indistinct or absent inframammary fold, who do not want a scar in the aesthetic unit of their chest.

  12. Transanal endoscopic microsurgery.

    Science.gov (United States)

    Smart, Christopher J; Cunningham, Chris; Bach, Simon P

    2014-02-01

    Transanal endoscopic microsurgery (TEMS) is a well established method of accurate resection of specimens from the rectum under binocular vision. This review examines its role in the treatment of benign conditions of the rectum and the evidence to support its use and compliment existing endoscopic treatments. The evolution of TEMS in early rectal cancer and the concepts and outcomes of how it has been utilised to treat patients so far are presented. The bespoke nature of early rectal cancer treatment is changing the standard algorithms of rectal cancer care. The future of TEMS in the organ preserving treatment of early rectal cancer is discussed and how as clinicians we are able to select the correct patients for neoadjuvant or radical treatments accurately. The role of radiotherapy and outcomes from combination treatment using TEMS are presented with suggestions for areas of future research. Copyright © 2014. Published by Elsevier Ltd.

  13. [GERD: endoscopic antireflux therapies].

    Science.gov (United States)

    Caca, K

    2006-08-02

    A couple of minimally-invasive, endoscopic antireflux procedures have been developed during the last years. Beside endoscopic suturing these included injection/implantation technique of biopolymers and application of radiofrequency. Radiofrequency (Stretta) has proved only a very modest effect, while implantation techniques have been abandoned due to lack of long-term efficacy (Gatekeeper) or serious side effects (Enteryx). While first generation endoluminal suturing techniques (EndoCinch, ESD) demonstrated a proof of principle their lack of durability, due to suture loss, led to the development of a potentially durable transmural plication technique (Plicator). In a prospective-randomized, sham-controlled trial the Plicator procedure proved superiority concerning reflux symptoms, medication use and esophageal acid exposure (24-h-pH-metry). While long-term data have to be awaited to draw final conclusions, technical improvements will drive innovation in this field.

  14. Endoscopic Treatment of Studer's Orthotopic Neobladder Lithiasis

    Directory of Open Access Journals (Sweden)

    Diogo Gil-Sousa

    2015-05-01

    Full Text Available Studer's neobladder lithiasis is a rare but important long term complication of this orthotopic bladder substitute technique. We report a case of a 45 year-old male patient, submitted to a radical cystoprostatectomy with a Studer's orthotopic neobladder 4 years before, presenting bad compliance to recommended urinary habits, increased production of mucus and high post voiding residue. CT scan and urethrocystography showed a distended pouch with 2 major sacculations with narrow communication and a stone in each sacculation. A minimally invasive endoscopic technique was successfully used in the treatment of the 2 small calculus.

  15. Endoscopic tissue diagnosis of cholangiocarcinoma.

    LENUS (Irish Health Repository)

    Harewood, Gavin C

    2008-09-01

    The extremely poor outcome in patients with cholangiocarcinoma, in large part, reflects the late presentation of these tumors and the challenging nature of establishing a tissue diagnosis. Establishing a diagnosis of cholangiocarcinoma requires obtaining evidence of malignancy from sampling of the epithelium of the biliary tract, which has proven to be challenging. Although endoscopic ultrasound-guided fine needle aspiration performs slightly better than endoscopic retrograde cholangiopancreatography in diagnosing cholangiocarcinoma, both endoscopic approaches demonstrate disappointing performance characteristics.

  16. Novel methods for endoscopic training.

    Science.gov (United States)

    Gessner, C E; Jowell, P S; Baillie, J

    1995-04-01

    The development of past, present, and future endoscopic training methods is described. A historical perspective of endoscopy training guidelines and devices is used to demonstrate support for the use of novel endoscopic training techniques. Computer simulation of endoscopy, interactive learning, and virtual reality applications in endoscopy and surgery are reviewed. The goals of endoscopic simulation and challenges facing investigators in this field are discussed, with an emphasis on current and future research.

  17. Mirizzi Syndrome with Endoscopic Ultrasound Image

    Directory of Open Access Journals (Sweden)

    K. Rayapudi

    2013-05-01

    Full Text Available We describe a 66-year-old Caucasian man with type 1 Mirizzi syndrome diagnosed on endoscopic ultrasound. He presented with acute onset of jaundice, malaise, dark urine over 3-4 days, and was found to have obstructive jaundice on lab testing. CT scan of the abdomen showed intrahepatic biliary ductal dilation, a 1.5 cm common bile duct (CBD above the pancreas, and possible stones in the CBD, but no masses. Endoscopic retrograde cholangiopancreatography (ERCP by a community gastroenterologist failed to cannulate the CBD. At the University Center, type 1 Mirizzi syndrome was noted on endoscopic ultrasound with narrowing of the CBD with extrinsic compression from cystic duct stone. During repeat ERCP, the CBD could be cannulated over the pancreatic duct wire. A mid CBD narrowing, distal CBD stones, proximal CBD and extrahepatic duct dilation were noted, and biliary sphincterotomy was performed. A small stone in the distal CBD was removed with an extraction balloon. The cystic duct stone was moved with the biliary balloon into the CBD, mechanical basket lithotripsy was performed and stone fragments were delivered out with an extraction balloon. The patient was seen 7 weeks later in the clinic. Skin and scleral icterus had cleared up and he is scheduled for an elective cholecystectomy. Mirizzi syndrome refers to biliary obstruction resulting from impacted stone in the cystic duct or neck of the gallbladder and commonly presents with obstructive jaundice. Type 1 does not have cholecystocholedochal fistulas, but they present in types 2, 3 and 4. Surgery is the mainstay of therapy. Endoscopic treatment is effective and can also be used as a temporizing measure or definitive treatment in poor surgical risk candidates.

  18. Large Scale Scanning Probe Microscope "Making Shear Force Scanning visible."

    NARCIS (Netherlands)

    Bosma, E.; Offerhaus, Herman L.; van der Veen, Jan T.; van der Veen, J.T.; Segerink, Franciscus B.; Wessel, I.M.

    2010-01-01

    We describe a demonstration of a scanning probe microscope with shear-force tuning fork feedback. The tuning fork is several centimeters long, and the rigid fiber is replaced by a toothpick. By scaling this demonstration to visible dimensions the accessibility of shear-force scanning and tuning fork

  19. Esophageal Perforation due to Transesophageal Echocardiogram: New Endoscopic Clip Treatment

    Directory of Open Access Journals (Sweden)

    John Robotis

    2014-07-01

    Full Text Available Esophageal perforation due to transesophageal echocardiogram (TEE during cardiac surgery is rare. A 72-year-old female underwent TEE during an operation for aortic valve replacement. Further, the patient presented hematemesis. Gastroscopy revealed an esophageal bleeding ulcer. Endoscopic therapy was successful. Although a CT scan excluded perforation, the patient became febrile, and a second gastroscopy revealed a big perforation at the site of ulcer. The patient's clinical condition required endoscopic intervention with a new OTSC® clip (Ovesco Endoscopy, Tübingen, Germany. The perforation was successfully sealed. The patient remained on intravenous antibiotics, proton pump inhibitors and parenteral nutrition for few days, followed by enteral feeding. She was discharged fully recovered 3 months later. We clearly demonstrate an effective, less invasive treatment of an esophageal perforation with a new endoscopic clip.

  20. Endoscopic transmission of Helicobacter pylori

    NARCIS (Netherlands)

    Tytgat, G. N.

    1995-01-01

    The contamination of endoscopes and biopsy forceps with Helicobacter pylori occurs readily after endoscopic examination of H. pylori-positive patients. Unequivocal proof of iatrogenic transmission of the organism has been provided. Estimates for transmission frequency approximate to 4 per 1000

  1. Ultrafast supercontinuum fiber-laser based pump-probe scanning magneto-optical Kerr effect microscope for the investigation of electron spin dynamics in semiconductors at cryogenic temperatures with picosecond time and micrometer spatial resolution.

    Science.gov (United States)

    Henn, T; Kiessling, T; Ossau, W; Molenkamp, L W; Biermann, K; Santos, P V

    2013-12-01

    We describe a two-color pump-probe scanning magneto-optical Kerr effect microscope which we have developed to investigate electron spin phenomena in semiconductors at cryogenic temperatures with picosecond time and micrometer spatial resolution. The key innovation of our microscope is the usage of an ultrafast "white light" supercontinuum fiber-laser source which provides access to the whole visible and near-infrared spectral range. Our Kerr microscope allows for the independent selection of the excitation and detection energy while avoiding the necessity to synchronize the pulse trains of two separate picosecond laser systems. The ability to independently tune the pump and probe wavelength enables the investigation of the influence of excitation energy on the optically induced electron spin dynamics in semiconductors. We demonstrate picosecond real-space imaging of the diffusive expansion of optically excited electron spin packets in a (110) GaAs quantum well sample to illustrate the capabilities of the instrument.

  2. Dosimetry in endoscopic examinations

    International Nuclear Information System (INIS)

    Aldred, Martha Aurelia; Paes, Walter Siqueira; Fausto, Agnes M.F.; Nucci, Jose Roberto; Yoshimura, Elisabeth Mateus; Okuno, Emico; Maruta, Luis Massuo

    1996-01-01

    Equivalent and effective doses in occupational exposures are evaluated considering that some specific endoscopic examinations, radiographic and fluoroscopic images of patients are taken with the medical staff near to the radiation field. Examinations are simulated using an anthropomorphic phantom as a member of the medical staff. Thermoluminescent dosemeters are attached in several positions of the phantom in order to determine some organ doses. From the comparison between the doses experimentally determined and the International and the Brazilian recommended occupational dose limits, the maximum number of examination that any member of the staff can perform was calculated

  3. Craniopharyngioma - Transnasal Endoscopic Approach

    Directory of Open Access Journals (Sweden)

    Sanjeev Bhagat,

    2011-01-01

    Full Text Available Craniopharyngiomas are slow growing tumours arising from remnants of the craniopharyngeal duct and occupy the sellar region. The patients may remain asymptomatic for long duration or present with headache or visual disturbances. Surgery is the mainstay of the treatment. Traditionally these tumours have been removed by neurosurgeons through the cranial approach but the advent of nasal endoscopes has opened new avenues for ENT surgeons to treat such patients. We hereby present a case of craniopharyngioma who was successfully treated by Trans-nasal Hypophysectomy.

  4. Endoscopic resection of subepithelial tumors.

    Science.gov (United States)

    Schmidt, Arthur; Bauder, Markus; Riecken, Bettina; Caca, Karel

    2014-12-16

    Management of subepithelial tumors (SETs) remains challenging. Endoscopic ultrasound (EUS) has improved differential diagnosis of these tumors but a definitive diagnosis on EUS findings alone can be achieved in the minority of cases. Complete endoscopic resection may provide a reasonable approach for tissue acquisition and may also be therapeutic in case of malignant lesions. Small SET restricted to the submucosa can be removed with established basic resection techniques. However, resection of SET arising from deeper layers of the gastrointestinal wall requires advanced endoscopic methods and harbours the risk of perforation. Innovative techniques such as submucosal tunneling and full thickness resection have expanded the frontiers of endoscopic therapy in the past years. This review will give an overview about endoscopic resection techniques of SET with a focus on novel methods.

  5. Ultrahigh speed en face OCT capsule for endoscopic imaging.

    Science.gov (United States)

    Liang, Kaicheng; Traverso, Giovanni; Lee, Hsiang-Chieh; Ahsen, Osman Oguz; Wang, Zhao; Potsaid, Benjamin; Giacomelli, Michael; Jayaraman, Vijaysekhar; Barman, Ross; Cable, Alex; Mashimo, Hiroshi; Langer, Robert; Fujimoto, James G

    2015-04-01

    Depth resolved and en face OCT visualization in vivo may have important clinical applications in endoscopy. We demonstrate a high speed, two-dimensional (2D) distal scanning capsule with a micromotor for fast rotary scanning and a pneumatic actuator for precision longitudinal scanning. Longitudinal position measurement and image registration were performed by optical tracking of the pneumatic scanner. The 2D scanning device enables high resolution imaging over a small field of view and is suitable for OCT as well as other scanning microscopies. Large field of view imaging for screening or surveillance applications can also be achieved by proximally pulling back or advancing the capsule while scanning the distal high-speed micromotor. Circumferential en face OCT was demonstrated in living swine at 250 Hz frame rate and 1 MHz A-scan rate using a MEMS tunable VCSEL light source at 1300 nm. Cross-sectional and en face OCT views of the upper and lower gastrointestinal tract were generated with precision distal pneumatic longitudinal actuation as well as proximal manual longitudinal actuation. These devices could enable clinical studies either as an adjunct to endoscopy, attached to an endoscope, or as a swallowed tethered capsule for non-endoscopic imaging without sedation. The combination of ultrahigh speed imaging and distal scanning capsule technology could enable both screening and surveillance applications.

  6. Nuclear Scans

    Science.gov (United States)

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  7. Non-endoscopic Mechanical Endonasal Dacryocystorhinostomy

    Directory of Open Access Journals (Sweden)

    Mohammad Etezad Razavi

    2011-01-01

    Full Text Available To circumvent the disadvantages of endoscopic dacryocystorhinostomy such as small rhinostomy size, high failure rate and expensive equipment, we hereby introduce a modified technique of non-endoscopic mechanical endonasal dacryocystorhinostomy (NE-MEDCR. Surgery is performed under general anesthesia with local decongestion of the nasal mucosa. A 20-gauge vitrectomy light probe is introduced through the upper canaliculus until it touches the bony medial wall of the lacrimal sac. While directly viewing the transilluminated target area, a nasal speculum with a fiber optic light carrier is inserted. An incision is made vertically or in a curvilinear fashion on the nasal mucosa in the lacrimal sac down to the bone using a Freer periosteum elevator. Approximately 1 to 1.5 cm of nasal mucosa is removed with Blakesley forceps. Using a lacrimal punch, the thick bone of the frontal process of the maxilla is removed and the inferior half of the sac is uncovered. The lacrimal sac is tented into the surgical site with the light probe and its medial wall is incised using a 3.2 mm keratome and then excised using the Blakesley forceps. The procedure is completed by silicone intubation. The NE-MEDCR technique does not require expensive instrumentation and is feasible in any standard ophthalmic surgical setting.

  8. Endoscopic approach to achalasia

    Science.gov (United States)

    Müller, Michaela; Eckardt, Alexander J; Wehrmann, Till

    2013-01-01

    Achalasia is a primary esophageal motor disorder. The etiology is still unknown and therefore all treatment options are strictly palliative with the intention to weaken the lower esophageal sphincter (LES). Current established endoscopic therapeutic options include pneumatic dilation (PD) or botulinum toxin injection. Both treatment approaches have an excellent symptomatic short term effect, and lead to a reduction of LES pressure. However, the long term success of botulinum toxin (BT) injection is poor with symptom recurrence in more than 50% of the patients after 12 mo and in nearly 100% of the patients after 24 mo, which commonly requires repeat injections. In contrast, after a single PD 40%-60% of the patients remain asymptomatic for ≥ 10 years. Repeated on demand PD might become necessary and long term remission can be achieved with this approach in up to 90% of these patients. The main positive predictors for a symptomatic response to PD are an age > 40 years, a LES-pressure reduction to 40 years, was nearly equivalent to surgery. A new promising technique might be peroral endoscopic myotomy, although long term results are needed and practicability as well as safety issues must be considered. Treatment with a temporary self expanding stent has been reported with favorable outcomes, but the data are all from one study group and must be confirmed by others before definite recommendations can be made. In addition to its use as a therapeutic tool, endoscopy also plays an important role in the diagnosis and surveillance of patients with achalasia. PMID:23951393

  9. Peroral endoscopic myotomy

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Peroral endoscopic myotomy (POEM) incorporatesconcepts of natural orifice translumenal endoscopicsurgery and achieves endoscopic myotomy by utilizinga submucosal tunnel as an operating space.Although intended for the palliation of symptoms ofachalasia, there is mounting data to suggest it is alsoefficacious in the management of spastic esophagealdisorders. The technique requires an understanding ofthe pathophysiology of esophageal motility disorders aswell as knowledge of surgical anatomy of the foregut.POEM achieves short term response in 82% to 100% ofpatients with minimal risk of adverse events. In addition,it appears to be effective and safe even at the extremesof age and regardless of prior therapy undertaken.Although infrequent, the ability of the endoscopist tomanage an intraprocedural adverse event is critical asfailure to do so could result in significant morbidity. Themajor late adverse event is gastroesophageal refluxwhich appears to occur in 20% to 46% of patients.Research is being conducted to clarify the optimaltechnique for POEM and a personalized approach bymeasuring intraprocedural esophagogastric junctiondistensibility appears promising. In addition toesophageal disorders,POEM is being studied in themanagement of gastroparesis (gastric pyloromyotomy)with initial reports demonstrating technical feasibility.Although POEM represents a paradigm shift themanagement of esophageal motility disorders, theresults of prospective randomized controlled trials withlong-term follow up are eagerly awaited.

  10. High-quality endoscope reprocessing decreases endoscope contamination.

    Science.gov (United States)

    Decristoforo, P; Kaltseis, J; Fritz, A; Edlinger, M; Posch, W; Wilflingseder, D; Lass-Flörl, C; Orth-Höller, D

    2018-02-24

    Several outbreaks of severe infections due to contamination of gastrointestinal (GI) endoscopes, mainly duodenoscopes, have been described. The rate of microbial endoscope contamination varies dramatically in literature. The aim of this multicentre prospective study was to evaluate the hygiene quality of endoscopes and automated endoscope reprocessors (AERs) in Tyrol/Austria. In 2015 and 2016, a total of 463 GI endoscopes and 105 AERs from 29 endoscopy centres were analysed by a routine (R) and a combined routine and advanced (CRA) sampling procedure and investigated for microbial contamination by culture-based and molecular-based analyses. The contamination rate of GI endoscopes was 1.3%-4.6% according to the national guideline, suggesting that 1.3-4.6 patients out of 100 could have had contacts with hygiene-relevant microorganisms through an endoscopic intervention. Comparison of R and CRA sampling showed 1.8% of R versus 4.6% of CRA failing the acceptance criteria in phase I and 1.3% of R versus 3.0% of CRA samples failing in phase II. The most commonly identified indicator organism was Pseudomonas spp., mainly Pseudomonas oleovorans. None of the tested viruses were detected in 40 samples. While AERs in phase I failed (n = 9, 17.6%) mainly due to technical faults, phase II revealed lapses (n = 6, 11.5%) only on account of microbial contamination of the last rinsing water, mainly with Pseudomonas spp. In the present study the contamination rate of endoscopes was low compared with results from other European countries, possibly due to the high quality of endoscope reprocessing, drying and storage. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  11. Optical transfection using an endoscope-like system.

    Science.gov (United States)

    Ma, Nan; Gunn-Moore, Frank; Dholakia, Kishan

    2011-02-01

    Optical transfection is a powerful method for targeted delivery of therapeutic agents to biological cells. A tightly focused pulsed laser beam may transiently change the permeability of a cell membrane to facilitate the delivery of foreign genetic material into cells. We report the first realization of an endoscope-like integrated system for optical transfection. An imaging fiber (coherent optical fiber bundle) with ∼ 6000 cores (pixels) embedded in a fiber cladding of ∼ 300 μm in diameter, produces an image circle (area) of ∼ 270 μm diam. This imaging fiber, with an ordered axicon lens array chemically etched at its exit face, is used for the delivery of a femtosecond laser to the cell membrane for optical transfection along with subcellular resolution imaging. A microcapillary-based microfluidic system for localized drug delivery was also combined in this miniature, flexible system. Using this novel system, a plasmid transfection efficiency up to ∼ 72% was obtained for CHO-K1 cells. This endoscope-like system opens a range of exciting applications, in particular, in the targeted in vivo optical microsurgery area.

  12. Successful endoscopic treatment of gastric phytobezoar: A case report.

    Science.gov (United States)

    Ugenti, Ippazio; Travaglio, Elisabetta; Lagouvardou, Elpiniki; Caputi Iambrenghi, Onofrio; Martines, Gennaro

    2017-01-01

    Gastric bezoars are a rare condition associated with situations of gastric dysmotility and prior gastric surgery, though sometimes they can present without any risk factor. We describe the first successful treatment in medical literature of a large gastric bezoar in the outpatient setting through endoscopic fragmentation. A 76-year-old man was referred to our outpatient endoscopy clinic because of dyspepsia and epigastric pain. Upper GI endoscopy with a standard endoscope revealed a 10-cm-diameter gastric phytobezoar with necrotic pressure ulcer of the angulus. We fragmentized the bezoar into smaller pieces, with complete dissolution and without any complication. The patient was then promptly discharged home with a medical therapy. Follow-up endoscopy at 6 months showed the total disappearance of any residual fibers. Different types of bezoars are described in literature, of which phyto- and trychobezoars are the most frequent. They can be absolutely asymptomatic or can arise with epigastric pain, pressure ulcer bleeding, gastrointestinal perforation or small bowel obstruction. The treatment is debated though endoscopic removal or fragmentation with the help of Coca-Cola lavages has showed the best success rate. The main experiences in literature concern hospitalized patients or describe treatment techniques which require overnight stays. An effective and rapid treatment in the outpatient setting is described in our experience, without short- or long-term complications. The endoscopic fragmentation of large gastric bezoars in the outpatient setting is safe with a good clinical course. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  13. Huge biloma after endoscopic retrograde cholangiopancreatography and endoscopic biliary sphincterotomy

    Directory of Open Access Journals (Sweden)

    Harith M. Alkhateeb

    2015-01-01

    Conclusions: (1 Following endoscopic retrograde cholangiopancreatography, a patient’s complaints should not be ignored. (2 A massive biloma can occur due to such procedures. (3 Conservative treatment with minimal invasive technique can prove to be effective.

  14. Endoscopic retrograde cholanglopancreatography

    International Nuclear Information System (INIS)

    Horii, S.C.; Garra, B.S.; Zeman, R.K.; Krasner, B.H.; Lo, S.C.B.; Davros, W.J.; Silverman, P.M.; Cattau, E.L.; Fleischer, D.E.; Benjamin, S.B.S.B.

    1989-01-01

    As part of the clinical evaluation of image management and communications system (IMACS), the authors undertook a prospective study to compare conventional film versus digitized film viewed on a workstation. Twenty-five each of normal and abnormal endoscopic retrograde cholangiopancreatographic (ERCP) studies were digitized with a 1,684 x 2,048-pixel matrix and evaluated in a single-blind fashion on the workstation. The resulting interpretations were then compared with those resulting from interpretation of film (spot film and 100-mm photospot) images. They report that no significant differences were found in ability to see anatomic detail or pathology. A second study involved performing 10 ERCP studies in a lithotripsy suite equipped with biplane digital fluoroscopy. The digital video displays were comparable in quality to that of film. Progress is being made in using the IMACS for archiving and retrieval of all current ERCP images

  15. Percutaneous endoscopic gastrostomy.

    Science.gov (United States)

    Gay, F; el Nawar, A; Van Gossum, A

    1992-01-01

    From March 87 to March 92, fifty eight patients were referred to our department for percutaneous endoscopic gastrostomy (PEG). The modality of the feeding tube insertion is described. The most common indications for placement were neurologic disorders in 62% of the cases (n = 36) and malignant diseases in 32% (n = 19). The success rate of the technique was 98.3% (n = 57). No procedure-related mortality was observed. A low rate of major complication (1.7%) and minor complication (10.5%) was noted. Feeding tubes were removed in 21% of patients (n = 12); none of them with malignant disease. Survival curve analysis demonstrated that 50% of patients died within 3 months of PEG placement. Such results raise questions about the selection of patients undergoing PEG. Our experience of patients undergoing PEG. Our experience suggests that PEG is easy and safe, even in debilitated patients, having an acceptable life expectancy.

  16. Endoscopic third ventriculostomy

    Directory of Open Access Journals (Sweden)

    Yad Ram Yadav

    2012-01-01

    Full Text Available Endoscopic third ventriculostomy (ETV is considered as a treatment of choice for obstructive hydrocephalus. It is indicated in hydrocephalus secondary to congenital aqueductal stenosis, posterior third ventricle tumor, cerebellar infarct, Dandy-Walker malformation, vein of Galen aneurism, syringomyelia with or without Chiari malformation type I, intraventricular hematoma, post infective, normal pressure hydrocephalus, myelomeningocele, multiloculated hydrocephalus, encephalocele, posterior fossa tumor and craniosynostosis. It is also indicated in block shunt or slit ventricle syndrome. Proper Pre-operative imaging for detailed assessment of the posterior communicating arteries distance from mid line, presence or absence of Liliequist membrane or other membranes, located in the prepontine cistern is useful. Measurement of lumbar elastance and resistance can predict patency of cranial subarachnoid space and complex hydrocephalus, which decides an ultimate outcome. Water jet dissection is an effective technique of ETV in thick floor. Ultrasonic contact probe can be useful in selected patients. Intra-operative ventriculo-stomography could help in confirming the adequacy of endoscopic procedure, thereby facilitating the need for shunt. Intraoperative observations of the patent aqueduct and prepontine cistern scarring are predictors of the risk of ETV failure. Such patients may be considered for shunt surgery. Magnetic resonance ventriculography and cine phase contrast magnetic resonance imaging are effective in assessing subarachnoid space and stoma patency after ETV. Proper case selection, post-operative care including monitoring of ICP and need for external ventricular drain, repeated lumbar puncture and CSF drainage, Ommaya reservoir in selected patients could help to increase success rate and reduce complications. Most of the complications develop in an early post-operative, but fatal complications can develop late which indicate an importance of

  17. Fiber webs

    Science.gov (United States)

    Roger M. Rowell; James S. Han; Von L. Byrd

    2005-01-01

    Wood fibers can be used to produce a wide variety of low-density three-dimensional webs, mats, and fiber-molded products. Short wood fibers blended with long fibers can be formed into flexible fiber mats, which can be made by physical entanglement, nonwoven needling, or thermoplastic fiber melt matrix technologies. The most common types of flexible mats are carded, air...

  18. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncica, Ana Maria; Saftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...

  19. Renal scan

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003790.htm Renal scan To use the sharing features on this ... anaphylaxis . Alternative Names Renogram; Kidney scan Images Kidney anatomy Kidney - blood and urine flow References Chernecky CC, ...

  20. CT Scan

    Science.gov (United States)

    ... disease, lung nodules and liver masses Monitor the effectiveness of certain treatments, such as cancer treatment Detect ... scan done in a hospital or an outpatient facility. CT scans are painless and, with newer machines, ...

  1. Ophthalmic comlications of functional endoscopic sinus surgery

    Directory of Open Access Journals (Sweden)

    Sergey A. Karpishchenko

    2017-03-01

    Full Text Available Functional endoscopic sinus surgery (FESS is an effective and safe surgical technique, which revolutionized the surgical management of nasal cavity and paranasal sinus diseases. The intimate connection between paranasal sinuses and the orbit places the orbital content at a risk of injury during sinus surgery, especially that of ethmoid sinuses. The orbit, the optic nerve, extraocular muscles and the lacrimal drainage system could be damaged during FESS. The risk of injury correlates to anatomical variations, degree and severity of disease, previous procedure results, and surgical experience. Ophthalmic complications can vary in severity from minor ones, such as localized hematomas, to extremely dangerous, such as optic nerve injury, that could lead to complete blindness. In order to minimize the risk of such complications, it is necessary to consider probable anatomic variations of paranasal sinuses and orbit, which are to be detected by CT scan before surgery.

  2. Endoscopic-assisted electrohydraulic shockwave lithotripsy in standing sedated horses.

    Science.gov (United States)

    Röcken, Michael; Fürst, Anton; Kummer, Martin; Mosel, Gesine; Tschanz, Theo; Lischer, Christoph J

    2012-07-01

    To report use of transendoscopic electrohydraulic shockwave lithotripsy for fragmentation of urinary calculi in horses. Case series. Male horses (n = 21). Fragmentation of cystic calculi (median, 6 cm diameter; range, 4-11 cm diameter) was achieved by transurethral endoscopy in standing sedated horses using an electrohydraulic shockwave fiber introduced through the biopsy channel of an endoscope. The fiber was advanced until it contacted the calculus. Repeated activation of the fiber was used to disrupt the calculus into fragments calculus removal was achieved in 20 horses (95%) with mean total surgical time of 168.6 minutes (range, 45-450). In the 20 horses with single calculi, 1-6 sessions were required to completely fragment the calculus. Except for 1 horse, in which perineal urethrotomy was eventually performed for complete fragment removal, fragments calculi were excreted via the urethra. Postoperative complications included hematuria because of severe mucosal erosion (n = 2), dysuria because of a trapped urethral fragment (2), small amount of urinary debris (1). One horse was euthanatized because of bladder rupture. Complete clearance of calculi and urinary debris was confirmed endoscopically 20 (3-45) days after the last session. Telephone follow-up (mean, 18.8 months; range, 7-24 months) revealed that horses had returned to previous activity levels without recurrence of clinical signs. Transendoscopic electrohydraulic lithotripsy appears to be an effective method for fragmentation of low-density calcium carbonate cystic calculi in male horses. Copyright 2012 by The American College of Veterinary Surgeons.

  3. The feasibility of endoscopy-CT image registration in the head and neck without prospective endoscope tracking.

    Directory of Open Access Journals (Sweden)

    W Scott Ingram

    Full Text Available Endoscopic examinations are frequently-used procedures for patients with head and neck cancer undergoing radiotherapy, but radiation treatment plans are created on computed tomography (CT scans. Image registration between endoscopic video and CT could be used to improve treatment planning and analysis of radiation-related normal tissue toxicity. The purpose of this study was to explore the feasibility of endoscopy-CT image registration without prospective physical tracking of the endoscope during the examination.A novel registration technique called Location Search was developed. This technique uses physical constraints on the endoscope's view direction to search for the virtual endoscope coordinates that maximize the similarity between the endoscopic video frame and the virtual endoscopic image. Its performance was tested on phantom and patient images and compared to an established registration technique, Frame-To-Frame Tracking.In phantoms, Location Search had average registration errors of 0.55 ± 0.60 cm for point measurements and 0.29 ± 0.15 cm for object surface measurements. Frame-To-Frame Tracking achieved similar results on some frames, but it failed on others due to the virtual endoscope becoming lost. This weakness was more pronounced in patients, where Frame-To-Frame tracking could not make it through the nasal cavity. On successful patient video frames, Location Search was able to find endoscope positions with an average distance of 0.98 ± 0.53 cm away from the ground truth positions. However, it failed on many frames due to false similarity matches caused by anatomical structural differences between the endoscopic video and the virtual endoscopic images.Endoscopy-CT image registration without prospective physical tracking of the endoscope is possible, but more development is required to achieve an accuracy suitable for clinical translation.

  4. Endoscope disinfection and its pitfalls--requirement for retrograde surveillance cultures.

    Science.gov (United States)

    Buss, A J; Been, M H; Borgers, R P; Stokroos, I; Melchers, W J; Peters, F T; Limburg, A J; Degener, J E

    2008-04-01

    Several endoscopy-related outbreaks of infection have been reported in recent years. For early recognition of inadequate disinfection of endoscopes we designed a microbiological surveillance system to evaluate the efficacy of the cleaning and disinfection procedure, and to trace disinfection problems to individual endoscopes or washer-disinfectors. Our surveillance protocol included anterograde and retrograde sampling, a decision algorithm, genetic fingerprinting, and scanning electron microscopy. Over a period of 29 months we found an increasing number of patient-ready endoscopes testing positive for Candida species other than albicans, especially C. parapsilosis. These yeasts were also isolated from the washer-disinfectors. The number of positive tests for Candida species varied from 1 out of 21 to 14 out of 27 samples from nine frequently used endoscopes. The number of colony-forming units per milliliter ranged from 1 - 10 to 3000 for endoscopes and 0.002 to 0.06 for the washer disinfectors. DNA fingerprinting was not able to discriminate different strains within C. parapsilosis. Our protocol was able to detect a structural problem in the endoscope disinfection process. Retrograde sampling was crucial for this purpose, because it has much higher sensitivity than anterograde sampling. Endoscopes with damaged working channels are probably the source of the contamination problem with Candida species.

  5. Structure-function relationship between the octopus perimeter cluster mean sensitivity and sector retinal nerve fiber layer thickness measured with the RTVue optical coherence tomography and scanning laser polarimetry.

    Science.gov (United States)

    Naghizadeh, Farzaneh; Garas, Anita; Vargha, Péter; Holló, Gábor

    2014-01-01

    To determine structure-function relationship between each of 16 Octopus perimeter G2 program clusters and the corresponding 16 peripapillary sector retinal nerve fiber layer thickness (RNFLT) values measured with the RTVue-100 Fourier-domain optical coherence tomography (RTVue OCT) and scanning laser polarimetry with variable corneal compensation (GDx-VCC) and enhanced corneal compensation (GDx-ECC) corneal compensation. One eye of 110 white patients (15 healthy, 20 ocular hypertensive, and 75 glaucoma eyes) were investigated. The Akaike information criterion and the F test were used to identify the best fitting model. Parabolic relationship with logarithmic cluster mean sensitivity and linear sector RNFLT values provided the best fit. For RTVue OCT, significant (P0.05) was found for the control eyes. Mean sensitivity of the Octopus visual field clusters showed significant parabolic relationship with the corresponding peripapillary RNFLT sectors. The relationship was more general with the RTVue OCT than GDx-VCC or GDx-ECC. The results show that visual field clusters of the Octopus G program can be applied for detailed structure-function research.

  6. Sphincter of Oddi stenosis: diagnosis using hepatobiliary scintigraphy and endoscopic manometry

    International Nuclear Information System (INIS)

    Lee, R.G.L.; Gregg, J.A.; Koroshetz, A.M.; Hill, T.C.; Clouse, M.E.

    1985-01-01

    To determine the role of radionuclide imaging in diagnosing sphincter of Oddi stenosis, 21 patients with symptoms suggesting this disorder underwent endoscopic retrograde cholangiopancreatography, cholescintigraphy, and, when possible, endoscopic manometry. Those patients with abnormal hepatobiliary scintigraphy results had a mean basal sphincter pressure of 38.5 mm Hg. Sphincter pressures could not be measured in six patients with sphincters too tight to cannulate. Ten patients who underwent hepatobiliary scanning both before and after sphincter surgery had normal scan results of the repeat study. Hepatobiliary imaging appears useful for diagnosis of sphincter of Oddi stenosis in selected patients in whom manometry cannot be performed and for objective assessment of response to therapy

  7. [Endoscopic full-thickness resection].

    Science.gov (United States)

    Meier, B; Schmidt, A; Caca, K

    2016-08-01

    Conventional endoscopic resection techniques such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are powerful tools for the treatment of gastrointestinal (GI) neoplasms. However, those techniques are limited to the superficial layers of the GI wall (mucosa and submucosa). Lesions without lifting sign (usually arising from deeper layers) or lesions in difficult anatomic positions (appendix, diverticulum) are difficult - if not impossible - to resect using conventional techniques, due to the increased risk of complications. For larger lesions (>2 cm), ESD appears to be superior to the conventional techniques because of the en bloc resection, but the procedure is technically challenging, time consuming, and associated with complications even in experienced hands. Since the development of the over-the-scope clips (OTSC), complications like bleeding or perforation can be endoscopically better managed. In recent years, different endoscopic full-thickness resection techniques came to the focus of interventional endoscopy. Since September 2014, the full-thickness resection device (FTRD) has the CE marking in Europe for full-thickness resection in the lower GI tract. Technically the device is based on the OTSC system and combines OTSC application and snare polypectomy in one step. This study shows all full-thickness resection techniques currently available, but clearly focuses on the experience with the FTRD in the lower GI tract.

  8. Antibiotic prophylaxis for patients undergoing elective endoscopic ...

    African Journals Online (AJOL)

    Antibiotic prophylaxis for patients undergoing elective endoscopic retrograde cholangiopancreatography. M Brand, D Bisoz. Abstract. Background. Antibiotic prophylaxis for endoscopic retrograde cholangiopancreatography (ERCP) is controversial. We set out to assess the current antibiotic prescribing practice among ...

  9. Endoscopic management of bile leaks after laparoscopic ...

    African Journals Online (AJOL)

    Endoscopic management of bile leaks after laparoscopic cholecystectomy. ... endoscopic management at a median of 12 days (range 2 - 104 days) after surgery. Presenting features included intra-abdominal collections with pain in 58 cases ...

  10. Evaluation of robotically controlled advanced endoscopic instruments

    NARCIS (Netherlands)

    Reilink, Rob; Kappers, Astrid M.L.; Stramigioli, Stefano; Misra, Sarthak

    Background Advanced flexible endoscopes and instruments with multiple degrees of freedom enable physicians to perform challenging procedures such as the removal of large sections of mucosal tissue. However, these advanced endoscopes are difficult to control and require several physicians to

  11. Triple Pancreatic Walled-off Fluid Collections Treated Simultaneously with Endoscopic Transmural Drainage.

    Science.gov (United States)

    Khalid, Sameen; Abbass, Aamer; Nellis, Eric; Shah, Shashin; Shah, Hiral

    2018-01-09

    Pancreatic pseudocysts and walled-off pancreatic necrosis arise as a complication of pancreatitis. Multiple fluid collections are seen in 5-20% of the patients who have walled-off peripancreatic fluid collections. There is a paucity of data regarding the role of endoscopic transmural drainage in the management of multiple pancreatic fluid collections. In this case report, we present the case of a 72-year-old male with three walled-off pancreatic fluid collections in the setting of acute necrotizing pancreatitis. The patient underwent simultaneous endoscopic ultrasound-assisted cyst gastrostomy and cyst duodenostomy and aggressive irrigation without index endoscopic necrosectomy of the three peripancreatic fluid collections. Significant improvement in the size of the fluid collections was seen on the computed tomography scan, as well as a remarkable immediate clinical improvement after 24 hours of the endoscopic intervention.

  12. Transoral endoscopic esophageal myotomy based on esophageal function testing in a survival porcine model.

    Science.gov (United States)

    Perretta, Silvana; Dallemagne, Bernard; Donatelli, Gianfranco; Diemunsch, Pierre; Marescaux, Jacques

    2011-01-01

    The most effective treatment of achalasia is Heller myotomy. To explore a submucosal endoscopic myotomy technique tailored on esophageal physiology testing and to compare it with the open technique. Prospective acute and survival comparative study in pigs (n = 12; 35 kg). University animal research center. Eight acute-4 open and 4 endoscopic-myotomies followed by 4 survival endoscopic procedures. Preoperative and postoperative manometry; esophagogastric junction (EGJ) distensibility before and after selective division of muscular fibers at the EGJ and after the myotomy was prolonged to a standard length by using the EndoFLIP Functional Lumen Imaging Probe (Crospon, Galway, Ireland). All procedures were successful, with no intraoperative and postoperative complications. In the survival group, the animals recovered promptly from surgery. Postoperative manometry demonstrated a 50% drop in mean lower esophageal sphincter pressure (LESp) in the endoscopic group (mean preoperative LESp, 22.2 ± 3.3 mm Hg; mean postoperative LESp, 11.34 ± 2.7 mm Hg; P open procedure group (mean preoperative LESp, 24.2 ± 3.2 mm Hg; mean postoperative LESp, 7.4 ± 4 mm Hg; P myotomy is feasible and safe. The lack of a significant difference in EGJ distensibility between the open and endoscopic procedure is very appealing. Were it to be perfected in a human population, this endoscopic approach could suggest a new strategy in the treatment of selected achalasia patients. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  13. Endoscopic Palliation for Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Mihir Bakhru

    2011-04-01

    Full Text Available Pancreatic cancer is devastating due to its poor prognosis. Patients require a multidisciplinary approach to guide available options, mostly palliative because of advanced disease at presentation. Palliation including relief of biliary obstruction, gastric outlet obstruction, and cancer-related pain has become the focus in patients whose cancer is determined to be unresectable. Endoscopic stenting for biliary obstruction is an option for drainage to avoid the complications including jaundice, pruritus, infection, liver dysfunction and eventually failure. Enteral stents can relieve gastric obstruction and allow patients to resume oral intake. Pain is difficult to treat in cancer patients and endoscopic procedures such as pancreatic stenting and celiac plexus neurolysis can provide relief. The objective of endoscopic palliation is to primarily address symptoms as well improve quality of life.

  14. Endoscopic inspection of steam turbines

    International Nuclear Information System (INIS)

    Maliniemi, H.; Muukka, E.

    1990-01-01

    For over ten years, Imatran Voima Oy (IVO) has developed, complementary inspection methods for steam turbine condition monitoring, which can be applied both during operation and shutdown. One important method used periodically during outages is endoscopic inspection. The inspection is based on the method where the internal parts of the turbine is inspected through access borings with endoscope and where the magnified figures of the internal parts is seen on video screen. To improve inspection assurance, an image-processing based pattern recognition method for cracks has been developed for the endoscopic inspection of turbine blades. It is based on the deduction conditions derived from the crack shape. The computer gives an alarm of a crack detection and prints a simulated image of the crack, which is then checked manually

  15. Fiber-integrated Brillouin microspectroscopy: Towards Brillouin endoscopy

    Directory of Open Access Journals (Sweden)

    Irina V. Kabakova

    2017-11-01

    Full Text Available Brillouin imaging (BI for micromechanical characterization of tissues and biomaterials is a fast-developing field of research with a strong potential for medical diagnosis of disease-modified tissues and cells. Although the principles of BI imply its compatibility with in vivo and in situ measurements, the integration of BI with a flexible catheter, capable of reaching the region of interest within the body, is yet to be reported. Here, for the first time, we experimentally investigate integration of the Brillouin spectroscope with standard optical fiber components to achieve a Brillouin endoscope. The performance of single-fiber and dual-fiber endoscopes are demonstrated and analyzed. We show that a major challenge in construction of Brillouin endoscopes is the strong backward Brillouin scattering in the optical fiber and we present a dual-fiber geometry as a possible solution. Measurements of Brillouin spectra in test liquids (water, ethanol and glycerol are demonstrated using the dual-fiber endoscope and its performance is analyzed numerically with the help of a beam propagation model.

  16. Coherent anti-Stokes Raman scattering rigid endoscope toward robot-assisted surgery.

    Science.gov (United States)

    Hirose, K; Aoki, T; Furukawa, T; Fukushima, S; Niioka, H; Deguchi, S; Hashimoto, M

    2018-02-01

    Label-free visualization of nerves and nervous plexuses will improve the preservation of neurological functions in nerve-sparing robot-assisted surgery. We have developed a coherent anti-Stokes Raman scattering (CARS) rigid endoscope to distinguish nerves from other tissues during surgery. The developed endoscope, which has a tube with a diameter of 12 mm and a length of 270 mm, achieved 0.91% image distortion and 8.6% non-uniformity of CARS intensity in the whole field of view (650 μm diameter). We demonstrated CARS imaging of a rat sciatic nerve and visualization of the fine structure of nerve fibers.

  17. Photorefractive Fibers

    National Research Council Canada - National Science Library

    Kuzyk, Mark G

    2003-01-01

    ... scope of the project. In addition to our work in optical limiting fibers, spillover results included making fiber-based light-sources, writing holograms in fibers, and developing the theory of the limits of the nonlinear...

  18. Endoscopic brow lifts uber alles.

    Science.gov (United States)

    Patel, Bhupendra C K

    2006-12-01

    Innumerable approaches to the ptotic brow and forehead have been described in the past. Over the last twenty-five years, we have used all these techniques in cosmetic and reconstructive patients. We have used the endoscopic brow lift technique since 1995. While no one technique is applicable to all patients, the endoscopic brow lift, with appropriate modifications for individual patients, can be used effectively for most patients with brow ptosis. We present the nuances of this technique and show several different fixation methods we have found useful.

  19. Cooperative scans

    NARCIS (Netherlands)

    M. Zukowski (Marcin); P.A. Boncz (Peter); M.L. Kersten (Martin)

    2004-01-01

    textabstractData mining, information retrieval and other application areas exhibit a query load with multiple concurrent queries touching a large fraction of a relation. This leads to individual query plans based on a table scan or large index scan. The implementation of this access path in most

  20. [Observing effect of treatment of the second branchial fistula with endoscopic resection].

    Science.gov (United States)

    Jiang, Jiping; Wang, Shuyun; Tong, Kang

    2014-03-01

    To explore synergic effect of treatment of the second branchial fistula with endoscopic resection. All patients of the second branchial fistula were scanned in neck with CT (computed tomography), we injected ioversol-320 from the entrance of the second branchial fistula in front of sternocleidomastiod into the second branchial fistula, then scanned the neck with CT (computed tomography), and rebuilding the picture of the second branchial fistula, to prepare for the operation. 9 patients of the second branchial fistula were operated under general anesthesia with endoscopic resection. All of 9 patients were cured. no one recurred after follow-up of 6 months. It is minimally invasive and complete to resect the second branchial with endoscopic resection, the operation is simply and easy to promote.

  1. Radionuclide scanning

    International Nuclear Information System (INIS)

    Shapiro, B.

    1986-01-01

    Radionuclide scanning is the production of images of normal and diseased tissues and organs by means of the gamma-ray emissions from radiopharmaceutical agents having specific distributions in the body. The gamma rays are detected at the body surface by a variety of instruments that convert the invisible rays into visible patterns representing the distribution of the radionuclide in the body. The patterns, or images, obtained can be interpreted to provide or to aid diagnoses, to follow the course of disease, and to monitor the management of various illnesses. Scanning is a sensitive technique, but its specificity may be low when interpreted alone. To be used most successfully, radionuclide scanning must be interpreted in conjunction with other techniques, such as bone radiographs with bone scans, chest radiographs with lung scans, and ultrasonic studies with thyroid scans. Interpretation is also enhanced by providing pertinent clinical information because the distribution of radiopharmaceutical agents can be altered by drugs and by various procedures besides physiologic and pathologic conditions. Discussion of the patient with the radionuclide scanning specialist prior to the study and review of the results with that specialist after the study are beneficial

  2. Peroral endoscopic myotomy for achalasia

    NARCIS (Netherlands)

    Bredenoord, A. J.; Rösch, T.; Fockens, P.

    2014-01-01

    Treatment of achalasia is complicated by symptom recurrence and a significant risk for severe complications. Endoscopic myotomy was developed in the search for a highly efficacious treatment with lower risks. Since its introduction in 2010, several centers have adopted the technique and published

  3. Colonic perforation following endoscopic retrograde ...

    African Journals Online (AJOL)

    We highlight a potentially lethal complication of acute severe pancreatitis that may not be suspected in severely ill patients. A 41-year-old woman developed acute severe pancreatitis following endoscopic retrograde cholangiopancreatography (ERCP) for suspected choledocholithiasis. When her condition deteriorated ...

  4. Proximal design for a multimodality endoscope with multiphoton microscopy, optical coherence microscopy and visual modalities

    Science.gov (United States)

    Kiekens, Kelli C.; Talarico, Olivia; Barton, Jennifer K.

    2018-02-01

    A multimodality endoscope system has been designed for early detection of ovarian cancer. Multiple illumination and detection systems must be integrated in a compact, stable, transportable configuration to meet the requirements of a clinical setting. The proximal configuration presented here supports visible light navigation with a large field of view and low resolution, high resolution multiphoton microscopy (MPM), and high resolution optical coherence microscopy (OCM). All modalities are integrated into a single optical system in the endoscope. The system requires two light sources: a green laser for visible light navigation and a compact fiber based femtosecond laser for MPM and OCM. Using an inline wavelength division multiplexer, the two sources are combined into a single mode fiber. To accomplish OCM, a fiber coupler is used to separate the femtosecond laser into a reference arm and signal arm. The reflected reference arm and the signal from the sample are interfered and wavelength separated by a reflection grating and detected using a linear array. The MPM signal is collimated and goes through a series of filters to separate the 2nd and 3rd harmonics as well as twophoton excitation florescence (2PEF) and 3PEF. Each signal is independently detected on a photo multiplier tube and amplified. The visible light is collected by multiple high numerical aperture fibers at the endoscope tip which are bundled into one SMA adapter at the proximal end and connected to a photodetector. This integrated system design is compact, efficient and meets both optical and mechanical requirements for clinical applications.

  5. Intraluminal irrigation with fibers improves mucosal inflammation and atrophy in diversion colitis.

    Science.gov (United States)

    de Oliveira-Neto, Joaquim P; de Aguilar-Nascimento, José E

    2004-02-01

    We investigated the effect of irrigating the colorectal mucosa of patients with a colostomy using a solution of fibers. Eleven patients (10 male and 1 female; mean age, 34 y; age range, 16-49 y) with loop colostomy due to trauma underwent endoscopic evaluation of the rectum and the proximal and distal mucosa from the colostomy. An endoscopic score (range, 0-10) was used to quantify the intensity of the inflammation at the mucosa. Biopsies were taken from the colostomy border and from the rectum. The mean crypt depth of the five best-oriented glands was registered. Then the diverted colorectal segment was irrigated with a solution containing 5% fibers (10 g/d) for 7 d. The patients underwent repeated endoscopic and biopsy procedures, and then the colostomy was closed. The endoscopic score was higher (P Irrigation with fibers improves inflammation at the defunctionalized colon.

  6. Advanced esophageal cancer and esophageal stenosis endoscopic treatment

    International Nuclear Information System (INIS)

    Piazze, A. E mail: apiazze@hc.edu.uy

    2005-01-01

    Advanced esophageal cancer (AEC) is diagnosed during those stages in which surgery is possible, it is palliative for disphagia, with high morbimortality.In inoperable or irresectable cases, resorting to alternative treatment such as radiotherapy or endoscopy may palliate dsphagia.Endoscopically it is possible to place a transtumoral nasogastric catheter (NGC) for preoperative nutrition or branchial therapy (intratumoral iridium).It is possible to dilate the tumor and place and indwelling plastic or auto expandable prosthesis or to inject absolute intratumoral alcohol.There is and evaluation of results and morbimortality of personal case material through the retrospective study of 54 patients in whom 120 procedures such as those referred to above were carried out.The series includes 41 men and 13 women (3-1), 79.5% of which were of ages between 61 and 90.Optic fiber endoscopes or video endoscopes, coaxial dilators, hydro-pneumatic balloons, metallic guides and non industrial and autoexpandable plastic prosthesis were used; 34.1% of procedures were performed under used; 34.1% of procedures were performed under radioscopy.Eleven patient (8 for nutritional purposes and 3 for brachiotherapy)form part of Groups 1 and 2 of NGC.Group 3 consist of:dilations of radicular stenosis with or without neopasic recurrence, or neoplasic infiltration of esophagus, 6 patient; Group 4: 14 patients for the purpose of dilation of esophageal neoplasm; Group 5:prosthesis, 12 patients; Group 6: 11 patients with anastomotic stenosis.In patients in Group 1-2-3 solution was achieved.In Group 3 there was 1 perforation.In Group 4, out of 14 patient 13 were dilated.In Group 5 it proved impossible to place prosthesis in 2 patient, (3.7%).The conclusion arrived at is that various endoscopic techniques may palliate disphagia in patient with AEC, collaborate with preoperative nutrition through enteral path, with brachioterapy or by treating post surgical stenosis, with low mortality

  7. Accuracy of endoscopic intraoperative assessment of urologic stone size.

    Science.gov (United States)

    Patel, Nishant; Chew, Ben; Knudsen, Bodo; Lipkin, Michael; Wenzler, David; Sur, Roger L

    2014-05-01

    Endoscopic treatment of renal calculi relies on surgeon assessment of residual stone fragment size for either basket removal or for the passage of fragments postoperatively. We therefore sought to determine the accuracy of endoscopic assessment of renal calculi size. Between January and May 2013, five board-certified endourologists participated in an ex vivo artificial endoscopic simulation. A total of 10 stones (pebbles) were measured (mm) by nonparticipating urologist (N.D.P.) with electronic calibers and placed into separate labeled opaque test tubes to prevent visualization of the stones through the side of the tube. Endourologists were blinded to the actual size of the stones. A flexible digital ureteroscope with a 200-μm core sized laser fiber in the working channel as a size reference was placed through the ureteroscope into the test tube to estimate the stone size (mm). Accuracy was determined by obtaining the correlation coefficient (r) and constructing an Altman-Bland plot. Endourologists tended to overestimate actual stone size by a margin of 0.05 mm. The Pearson correlation coefficient was r=0.924, with a p-valuestones (stones (≥4 mm), r=0.911 vs r=0.666. Altman-bland plot analysis suggests that surgeons are able to accurately estimate stone size within a range of -1.8 to +1.9 mm. This ex vivo simulation study demonstrates that endoscopic assessment is reliable when assessing stone size. On average, there was a slight tendency to overestimate stone size by 0.05 mm. Most endourologists could visually estimate stone size within 2 mm of the actual size. These findings could be generalized to state that endourologists are accurately able to intraoperatively assess residual stone fragment size to guide decision making.

  8. Fiber dielectrophoresis

    International Nuclear Information System (INIS)

    Lipowicz, P.J.; Yeh, H.C.

    1988-01-01

    Dielectrophoresis is the motion of uncharged particles in nonuniform electric fields. We find that the theoretical dielectrophoretic velocity of a conducting fiber in an insulating medium is proportional to the square of the fiber length, and is virtually independent of fiber diameter. This prediction has been verified experimentally. The results point to the development of a fiber length classifier based on dielectrophoresis. (author)

  9. Alternative Treatment of Osteoma Using an Endoscopic Holmium-YAG Laser

    Directory of Open Access Journals (Sweden)

    Ba Leun Han

    2012-07-01

    Full Text Available Osteoma is one of the most common tumors of the cranial vault and the facial skeleton. For osteoma in the facial region, endoscopic resection is widely used to prevent surgical scarring. Tumors in a total of 14 patients were resected using an endoscopic holmium-doped yttrium aluminium garnet (Ho:YAG laser with a long flexible fiber. Aside from having the advantage of not leaving a scar due to the use of endoscopy, this procedure allowed resection at any position, was minimally invasive, and caused less postoperative pain. This method yielded excellent cosmetic results, so the endoscopic Ho:YAG laser is expected to emerge as a good treatment option for osteoma.

  10. Fluorescence-Raman Dual Modal Endoscopic System for Multiplexed Molecular Diagnostics

    Science.gov (United States)

    Jeong, Sinyoung; Kim, Yong-Il; Kang, Homan; Kim, Gunsung; Cha, Myeong Geun; Chang, Hyejin; Jung, Kyung Oh; Kim, Young-Hwa; Jun, Bong-Hyun; Hwang, Do Won; Lee, Yun-Sang; Youn, Hyewon; Lee, Yoon-Sik; Kang, Keon Wook; Lee, Dong Soo; Jeong, Dae Hong

    2015-03-01

    Optical endoscopic imaging, which was recently equipped with bioluminescence, fluorescence, and Raman scattering, allows minimally invasive real-time detection of pathologies on the surface of hollow organs. To characterize pathologic lesions in a multiplexed way, we developed a dual modal fluorescence-Raman endomicroscopic system (FRES), which used fluorescence and surface-enhanced Raman scattering nanoprobes (F-SERS dots). Real-time, in vivo, and multiple target detection of a specific cancer was successful, based on the fast imaging capability of fluorescence signals and the multiplex capability of simultaneously detected SERS signals using an optical fiber bundle for intraoperative endoscopic system. Human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR) on the breast cancer xenografts in a mouse orthotopic model were successfully detected in a multiplexed way, illustrating the potential of FRES as a molecular diagnostic instrument that enables real-time tumor characterization of receptors during routine endoscopic procedures.

  11. Endoscopic OCT for in-vivo imaging of precancer and cancer states of human mucosa

    Science.gov (United States)

    Sergeev, Alexander M.; Gelikonov, Valentin M.; Gelikonov, Grigory V.; Feldchtein, Felix I.; Kuranov, Roman V.; Gladkova, Natalia D.; Shakhova, Natalia M.; Kuznetzova, Irina N.; Snopova, Ludmila; Denisenko, Arkady; Almasov, Valentin

    1998-01-01

    First results of endoscopic applications of optical coherence tomography for in vivo studies of human mucosa in gastrointestinal and genital tracts are presented. A novel endoscopic OCT system has ben created that is based on the integration of a sampling arm of an all-optical-fiber interferometer into standard endoscopic devices using their biopsy channel to transmit low-coherence radiation to investigated tissue. We have studied mucous membranes of esophagus, stomach and uterine cervix as typical localization for carcinomatous processes. Images of tumor tissues versus healthy tissues have been recorded and analyzed. Violations of well-defined stratified healthy mucosa structure in cancerous tissue is distinctly seen by EOCT, thus making this technique promising for early diagnosis of tumors and precise guiding of excisional biopsy.

  12. Integrated endoscopic OCT system and in-vivo images of human internal organs

    Science.gov (United States)

    Sergeev, Alexander M.; Gelikonov, Valentin M.; Gelikonov, Grigory V.; Feldchtein, Felix I.; Kuranov, Roman V.; Gladkova, Natalia D.; Shakhova, Natalia M.; Snopova, Ludmila; Shakhov, Andrei; Kuznetzova, Irina N.; Denisenko, Arkady; Pochinko, Vitaly; Chumakov, Yuri; Almasov, Valentin

    1998-04-01

    First results of endoscopic applications of optical coherence tomography (OCT) for in vivo studies of human mucosa in respiratory, gastrointestinal, urinary and genital tracts are presented. A novel endoscopic OCT (EOCT) system has been created that is based on the integration of a sampling arm of an all-optical-fiber interferometer into standard endoscopic devices using their biopsy channel to transmit low-coherence radiation to investigated tissue. We have studied mucous membranes of esophagus, larynx, stomach, urinary bladder, uterine cervix and endometrium as typical localization for carcinomatous processes. Images of tumor tissues versus healthy tissues have been recorded and analyzed. Violations of well-defined stratified healthy mucosa structure in cancered tissue is distinctly seen by EOCT, thus making this technique promising for early diagnosis of tumors and precise guiding of excisional biopsy.

  13. In vivo endoscopic OCT imaging of precancer and cancer states of human mucosa

    Science.gov (United States)

    Sergeev, Alexander M.; Gelikonov, V. M.; Gelikonov, G. V.; Feldchtein, Felix I.; Kuranov, R. V.; Gladkova, N. D.; Shakhova, N. M.; Snopova, L. B.; Shakhov, A. V.; Kuznetzova, I. A.; Denisenko, A. N.; Pochinko, V. V.; Chumakov, Yu P.; Streltzova, O. S.

    1997-12-01

    First results of endoscopic applications of optical coherence tomography for in vivo studies of human mucosa in respiratory, gastrointestinal, urinary and genital tracts are presented. A novel endoscopic OCT (EOCT) system has been created that is based on the integration of a sampling arm of an all-optical-fiber interferometer into standard endoscopic devices using their biopsy channel to transmit low-coherence radiation to investigated tissue. We have studied mucous membranes of esophagus, larynx, stomach, urinary bladder, uterine cervix and body as typical localization for carcinomatous processes. Images of tumor tissues versus healthy tissues have been recorded and analyzed. Violations of well-defined stratified healthy mucosa structure in cancered tissue are distinctly seen by EOCT, thus making this technique promising for early diagnosis of tumors and precise guiding of excisional biopsy.

  14. Fiber Amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten

    2017-01-01

    The chapter provides a discussion of optical fiber amplifiers and through three sections provides a detailed treatment of three types of optical fiber amplifiers, erbium doped fiber amplifiers (EDFA), Raman amplifiers, and parametric amplifiers. Each section comprises the fundamentals including...... the basic physics and relevant in-depth theoretical modeling, amplifiers characteristics and performance data as a function of specific operation parameters. Typical applications in fiber optic communication systems and the improvement achievable through the use of fiber amplifiers are illustrated....

  15. Textile composites based on natural fibers

    CSIR Research Space (South Africa)

    Li, Yan

    2009-04-01

    Full Text Available . The two kinds of fiber surface treatment methods were permanganate treatment and silane treatment. Vinyl ester was used as the matrix. The permeability values of sisal textile before and after fiber surface treatments are listed in Table 3. Comparisons... and more liquid resin flow through inter-bundles. Figure 4. Intra-bundle and inter-bundle flows As reported, permanganate, as an oxidant, can etch sisal fiber surface [20]. Scanning electronic micrograph of a permanganate treated sisal fiber...

  16. Endoscopic vs. Microscopic Resection of Sellar Lesions—A Matched Analysis of Clinical and Socioeconomic Outcomes

    Directory of Open Access Journals (Sweden)

    Tej D. Azad

    2017-06-01

    Full Text Available BackgroundDirect comparisons of microscopic and endoscopic resection of sellar lesions are scarce, with conflicting reports of cost and clinical outcome advantages.ObjectiveTo determine if the proposed benefits of endoscopic resection are realized on a population level.MethodsWe performed a matched cohort study of 9,670 adult patients in the MarketScan database who underwent either endoscopic or microscopic surgery for sellar lesions. Coarsened matching was applied to estimate the effects of surgical approach on complication rates, length of stay (LOS, costs, and likelihood of postoperative radiation.ResultsWe found that LOS, readmission, and revision rates did not differ significantly between approaches. The overall complication rate was higher for endoscopy (47% compared to 39%, OR 1.37, 95% CI 1.22–1.53. Endoscopic approach was associated with greater risk of neurological complications (OR 1.32, 95% CI 1.11–1.55, diabetes insipidus (OR 1.65, 95% CI 1.37–2.00, and cerebrospinal fluid rhinorrhea (OR 1.83, 95% CI 1.07–3.13 compared to the microscopic approach. Although the total index payment was higher for patients receiving endoscopic resection ($32,959 compared to $29,977 for microscopic resection, there was no difference in long-term payments. Endoscopic surgery was associated with decreased likelihood of receiving post-resection stereotactic radiosurgery (OR 0.67, 95% CI 0.49–0.90 and intensity-modulated radiation therapy (OR 0.78, 95% CI 0.65–0.93.ConclusionOur results suggest that the transition from a microscopic to endoscopic approach to sellar lesions must be subject to careful evaluation. Although there are evident advantages to transsphenoidal endoscopy, our analysis suggests that the benefits of the endoscopic approach are yet to be materialized.

  17. Method for Surface Scanning in Medical Imaging and Related Apparatus

    DEFF Research Database (Denmark)

    2015-01-01

    A method and apparatus for surface scanning in medical imaging is provided. The surface scanning apparatus comprises an image source, a first optical fiber bundle comprising first optical fibers having proximal ends and distal ends, and a first optical coupler for coupling an image from the image...

  18. Scoping the scope: endoscopic evaluation of endoscope working channels with a new high-resolution inspection endoscope (with video).

    Science.gov (United States)

    Barakat, Monique T; Girotra, Mohit; Huang, Robert J; Banerjee, Subhas

    2018-02-06

    Outbreaks of transmission of infection related to endoscopy despite reported adherence to reprocessing guidelines warrant scrutiny of all potential contributing factors. Recent reports from ambulatory surgery centers indicated widespread significant occult damage within endoscope working channels, raising concerns regarding the potential detrimental impact of this damage on the adequacy of endoscope reprocessing. We inspected working channels of all 68 endoscopes at our academic institution using a novel flexible inspection endoscope. Inspections were recorded and videos reviewed by 3 investigators to evaluate and rate channel damage and/or debris. Working channel rinsates were obtained from all endoscopes, and adenosine triphosphate (ATP) bioluminescence was measured. Overall endoscope working channel damage was rated as minimal and/or mild and was consistent with expected wear and tear (median 1.59 on our 5-point scale). Our predominant findings included superficial scratches (98.5%) and scratches with adherent peel (76.5%). No channel perforations, stains, or burns were detected. The extent of damage was not predicted by endoscope age. Minor punctate debris was common, and a few small drops of fluid were noted in 42.6% of endoscopes after reprocessing and drying. The presence of residual fluid predicted higher ATP bioluminescence values. The presence of visualized working channel damage or debris was not associated with elevated ATP bioluminescence values. The flexible inspection endoscope enables high-resolution imaging of endoscope working channels and offers endoscopy units an additional modality for endoscope surveillance, potentially complementing bacterial cultures and ATP values. Our study, conducted in a busy academic endoscopy unit, indicated predominately mild damage to endoscope working channels, which did not correlate with elevated ATP values. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights

  19. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncică, Ana Maria; Săftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...... cancers and visualization of the portal venous system and esophageal varices. In addition, contrast agents can be used to differentiate pancreatic lesions. The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies. The sensitivity of power Doppler...

  20. Advances in endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    WANG Xiangping

    2018-03-01

    Full Text Available Endoscopic retrograde cholangiopancreatography (ERCP is a well-established advanced endoscopic technique for the diagnosis and treatment of pancreatobiliary diseases. New advances have been made in the treatment concept and techniques of ERCP in recent years. This article elaborates on the recent advances in ERCP, including the application of pancreatic duct stent, non-steroidal anti-inflammatory drugs, and aggressive hydration to prevent postoperative pancreatitis, covered metal stent for the treatment of benign bile duct stenosis, intraluminal radiofrequency ablation for malignant bile duct stenosis, extracorporeal shockwave lithotripsy and covered metal stent for the treatment of chronic pancreatitis, peroral choledochoscopy for qualitative diagnosis of bile duct stenosis and huge refractory stones, definition of difficult intubation, timing of pre-cut technique, and ERCP after gastrointestinal reconstruction.

  1. Endoscopic ultrasound and pancreas divisum

    DEFF Research Database (Denmark)

    Rana, Surinder S; Gonen, Can; Vilmann, Peter

    2012-01-01

    Pancreas divisum is the most common congenital anatomic variation of the pancreatic ductal anatomy and in most of the individuals it is asymptomatic. However, in minority of individuals it is presumed to cause recurrent acute pancreatitis and chronic pancreatitis. Endoscopic retrograde cholangiop......Pancreas divisum is the most common congenital anatomic variation of the pancreatic ductal anatomy and in most of the individuals it is asymptomatic. However, in minority of individuals it is presumed to cause recurrent acute pancreatitis and chronic pancreatitis. Endoscopic retrograde...... of the parenchyma also. Therefore EUS, both radial and linear, has potential for being a minimally invasive diagnostic modality for pancreas divisum. A number of EUS criteria have been suggested for the diagnosis of pancreas divisum. These criteria have varying sensitivity and specificity and hence there is a need...

  2. Non-equilibrium atmospheric pressure microplasma jet: An approach to endoscopic therapies

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Xiao; Wei, Yu; Wei Chen, Long; Dong Meng, Yue [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Collaboration: Plasma Medicine Team

    2013-08-15

    Atmospheric pressure microplasma jet generated in a long hollow core optical fiber is studied to verify the potential feasibility of endoscopic therapies. Thermal damage and electric shock to the human body were suppressed by two technical methods, i.e., the high-voltage resistant flexible tube wrapped on the optical fiber and a power resistor of 100 kΩ connected between the power supply and the copper foil electrode. Optical emission spectra analysis indicated that many kinds of active radicals like excited atomic O and OH, were generated in the microplasma jet. In addition, the applications of the microplasma jet on sterilization and lung cancer cell apoptosis were presented. After 5 min of exposures to the microplasma jet, the cell viability and the bacillus subtilis replication decreased to about 3% and zero, respectively. More investigations are needed to improve the plasma-aided endoscopic therapies.

  3. Pancreas imaging by computed tomography after endoscopic retrograde pancreatography

    International Nuclear Information System (INIS)

    Frick, M.P.; O'Leary, J.F.; Salomonowitz, E.; Stoltenberg, E.; Hutton, S.; Gedgaudas, E.

    1984-01-01

    A method using CT after endoscopic retrograde pancreatography (CT-ERP) is described for pancreatic imaging. When using an ERP technique in the canine model comparable to that used in humans, small amounts of contrast material in peripheral pancreatic radicles resulted in enhancement of the pancreas on CT scans. Nine patients were also studied by CT-ERP images. The main pancreatic duct was seen on delayed images. In cases of chronic pancreatitis (n = 2), pancreatic opacification was patchy and heterogeneous. There was no contrast-material enhancement in areas of pancreatic carcimomas (n = 2). CT-ERP showed the true extent of carcinoma better than ERP alone

  4. Endoscopic Endonasal Management of Craniopharyngioma.

    Science.gov (United States)

    Zacharia, Brad E; Amine, Muhamad; Anand, Vijay; Schwartz, Theodore H

    2016-02-01

    Craniopharyngioma is a rare clinical entity that poses a significant management challenge given their location and propensity to recur. As part of a minimally disruptive treatment paradigm, the expanded endonasal approach has the potential to improve rates of resection, improve postoperative visual recovery, and minimize surgical morbidity. This article updates the otolaryngologic community on the basic principles and techniques regarding the incorporation of the endoscopic, endonasal approach in the management paradigm of craniopharyngioma. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Systems workplace for endoscopic surgery.

    Science.gov (United States)

    Irion, K M; Novak, P

    2000-01-01

    With the advent of minimally invasive surgery (MIS) a decade ago, the requirements for operating rooms (OR) and their equipment have been increased. Compared with conventional open surgery, the new endoscopic techniques require additional tools. Television systems, for video-assisted image acquisition and visualisation, including cameras, monitors and light systems, as well as insufflators, pumps, high-frequency units, lasers and motorised therapy units, are nowadays usually made available on carts during endoscopic surgery. In conjunction with a set of endoscopic instruments, these high-tech units allow new operating techniques to be performed. The benefit for patients has become clear in recent years; however, the technical complexity of OR has also increased considerably. To minimise this problem for the OR personnel, the MIS concept 'OR1' (Operating Room 1) was developed and implemented. OR1 is a fully functional and integrated multi-speciality surgical suite for MIS. The centrepieces of the OR1 are the Storz Communication Bus (SCB) and the advanced image and data archiving system (Aida) from Karl Storz, Tuttlingen, Germany. Both components allow monitoring, access and networking of the MIS equipment and other OR facilities, as well as the acquisition, storage and display of image, patient and equipment data during the endoscopic procedure. A central user interface allows efficient, simplified operation and online clinical images. Due to the system integration, the handling of complex equipment is considerably simplified, logistical procedures in the OR are improved, procedure times are shorter and, particularly noteworthy, operative risk can be reduced through simplified device operation.

  6. Endoscopic Management of Posterior Epistaxis

    OpenAIRE

    Paul, J.; Kanotra, Sohit Paul; Kanotra, Sonika

    2011-01-01

    The traditional method of management of posterior epistaxis has been with anteroposterior nasal packing. Apart from the high failure rate of 26–50% reported in various series, nasal packing is associated with marked discomfort and several complications. In order to avoid nasal packing, we started doing endoscopic cauterization in cases of posterior epistaxis. A total of 23 patients with posterior epistaxis were subjected to nasal endoscopy with the intent to stop bleeding by cauterization of ...

  7. Endoscopic treatment of esophageal achalasia.

    Science.gov (United States)

    Esposito, Dario; Maione, Francesco; D'Alessandro, Alessandra; Sarnelli, Giovanni; De Palma, Giovanni D

    2016-01-25

    Achalasia is a motility disorder of the esophagus characterized by dysphagia, regurgitation of undigested food, chest pain, weight loss and respiratory symptoms. The most common form of achalasia is the idiopathic one. Diagnosis largely relies upon endoscopy, barium swallow study, and high resolution esophageal manometry (HRM). Barium swallow and manometry after treatment are also good predictors of success of treatment as it is the residue symptomatology. Short term improvement in the symptomatology of achalasia can be achieved with medical therapy with calcium channel blockers or endoscopic botulin toxin injection. Even though few patients can be cured with only one treatment and repeat procedure might be needed, long term relief from dysphagia can be obtained in about 90% of cases with either surgical interventions such as laparoscopic Heller myotomy or with endoscopic techniques such pneumatic dilatation or, more recently, with per-oral endoscopic myotomy. Age, sex, and manometric type by HRM are also predictors of responsiveness to treatment. Older patients, females and type II achalasia are better after treatment compared to younger patients, males and type III achalasia. Self-expandable metallic stents are an alternative in patients non responding to conventional therapies.

  8. [Risk management for endoscopic surgery].

    Science.gov (United States)

    Kimura, Taizo

    2010-05-01

    The number of medical accidents in endoscopic surgery has recently increased. Surgical complications caused by inadequate preparation or immature technique or those resulting in serious adverse outcomes may be referred to as medical accidents. The Nationwide Survey of Endoscopic Surgery showed that bile duct injury and uncontrollable bleeding were seen in 0.68% and in 0.58%, respectively, of cholecystectomy patients; interoperative and postoperative complications in 0.84% and in 3.8%, respectively, of gastric cancer surgery patients; and operative complications in 6.74% of bowel surgery patients. Some required open repair, and 49 patients died. The characteristic causes of complications in endoscopic surgery are a misunderstanding of anatomy, handling of organs outside the visual field, burn by electrocautery, and injuries caused by forceps. Bleeding that requires a laparotomy for hemostasis is also a complication. Furthermore, since the surgery is usually videorecorded, immature techniques resulting in complications are easily discovered. To decrease the frequency of accidents, education through textbooks and seminars, training using training boxes, simulators, or animals, proper selection of the surgeon depending on the difficulty of the procedure, a low threshold for conversion to laparotomy, and use of the best optical equipment and surgical instruments are important. To avoid malpractice lawsuits, informed consent obtained before surgery and proper communication after accidents are necessary.

  9. Endoscopic treatment of esophageal achalasia

    Science.gov (United States)

    Esposito, Dario; Maione, Francesco; D’Alessandro, Alessandra; Sarnelli, Giovanni; De Palma, Giovanni D

    2016-01-01

    Achalasia is a motility disorder of the esophagus characterized by dysphagia, regurgitation of undigested food, chest pain, weight loss and respiratory symptoms. The most common form of achalasia is the idiopathic one. Diagnosis largely relies upon endoscopy, barium swallow study, and high resolution esophageal manometry (HRM). Barium swallow and manometry after treatment are also good predictors of success of treatment as it is the residue symptomatology. Short term improvement in the symptomatology of achalasia can be achieved with medical therapy with calcium channel blockers or endoscopic botulin toxin injection. Even though few patients can be cured with only one treatment and repeat procedure might be needed, long term relief from dysphagia can be obtained in about 90% of cases with either surgical interventions such as laparoscopic Heller myotomy or with endoscopic techniques such pneumatic dilatation or, more recently, with per-oral endoscopic myotomy. Age, sex, and manometric type by HRM are also predictors of responsiveness to treatment. Older patients, females and type II achalasia are better after treatment compared to younger patients, males and type III achalasia. Self-expandable metallic stents are an alternative in patients non responding to conventional therapies. PMID:26839644

  10. Endoscopic management of posterior epistaxis.

    Science.gov (United States)

    Paul, J; Kanotra, Sohit Paul; Kanotra, Sonika

    2011-04-01

    The traditional method of management of posterior epistaxis has been with anteroposterior nasal packing. Apart from the high failure rate of 26-50% reported in various series, nasal packing is associated with marked discomfort and several complications. In order to avoid nasal packing, we started doing endoscopic cauterization in cases of posterior epistaxis. A total of 23 patients with posterior epistaxis were subjected to nasal endoscopy with the intent to stop bleeding by cauterization of the bleeding vessel. Of these, in four cases unsuspected diagnosis was made. Of the remaining 19, in three patients, the bleeding point could not be localized accurately and these patients were managed by anteroposterior packing. The rest of the 16 patients were managed by endoscopic cauterization. In four patients, there was recurrence of bleeding within 24 h. In one of these, cauterization controlled the bleeding while in the rest nasal packing had to be resorted to. Thus, of the 23 patients of posterior epistaxis subjected to nasal endoscopy, we could avoid nasal packing in 17 (74%). To conclude, endoscopic nasal cauterization is recommended as the first line to treatment in all cases of posterior epistaxis. This will not only prevent the uncomfortable and potentially dangerous nasal packing but also help in finding the underlying pathology.

  11. Endoscopically removed giant submucosal lipoma

    Directory of Open Access Journals (Sweden)

    Jovanović Ivan

    2007-01-01

    Full Text Available Background. Although uncommon, giant submucosal colon lipomas merit attention as they are often presented with dramatic clinical features such as bleeding, acute bowel obstruction, perforation and sometimes may be mistaken for malignancy. There is a great debate in the literature as to how to treat them. Case report. A patient, 67-year old, was admitted to the Clinic due to a constipation over the last several months, increasing abdominal pain mainly localized in the left lower quadrant accompanied by nausea, vomiting and abdominal distension. Physical examination was unremarkable and the results of the detailed laboratory tests and carcinoembryonic antigen remained within normal limits. Colonoscopy revealed a large 10 cm long, and 4 to 5 cm in diameter, mobile lesion in his sigmoid colon. Conventional endoscopic ultrasound revealed 5 cm hyperechoic lesion of the colonic wall. Twenty MHz mini-probe examination showed that lesion was limited to the submucosa. Since polyp appeared too large for a single transaction, it was removed piecemeal. Once the largest portion of the polyp has been resected, it was relatively easy to place the opened snare loop around portions of the residual polyp. Endoscopic resection was carried out safely without complications. Histological examination revealed the common typical histological features of lipoma elsewhere. The patient remained stable and eventually discharged home. Four weeks later he suffered no recurrent symptoms. Conclusion. Colonic lipomas can be endoscopically removed safely eliminating unnecessary surgery.

  12. [Endoscopic ultrasound guided rendezvous for biliary drainage].

    Science.gov (United States)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem; Karstensen, John Gésdal

    2015-04-27

    Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from the stomach or duodenum to the common bile duct and from there on to the duodenum enabling ERCP. With a relatively high rate of success EUS-RV should be considered as an alternative to biliary drainage and surgical intervention.

  13. Endoscopic Medial Maxillectomy Breaking New Frontiers

    OpenAIRE

    Mohanty, Sanjeev; Gopinath, M.

    2011-01-01

    Endoscopy has changed the perspective of rhinologist towards the nose. It has revolutionised the surgical management of sinonasal disorders. Sinus surgeries were the first to get the benefit of endoscope. Gradually the domain of endoscopic surgery extended to the management of sino nasal tumours. Traditionally medial maxillectomy was performed through lateral rhinotomy or mid facial degloving approach. Endoscopic medial maxillectomy has been advocated by a number of authors in the management ...

  14. New techniques in gastrointestinal endoscopic surgery

    Directory of Open Access Journals (Sweden)

    Rafael Antonio Luengas Tello

    2012-09-01

    Full Text Available Gastrointestinal endoscopic surgery has been making great progress since the seventies in the management paradigms of conditions such as gastrointestinal bleeding, polyp resection and diagnostic and therapeutic management of the biliary tract. The current challenge is the development of techniques that allow endoscopic treatment of emerging diseases such as cancer, morbid obesity, gastro-esophageal reflux and achalasia. This article reports on new techniques and expectations for the future in the endoscopic management of these diseases.

  15. Scanning table

    CERN Multimedia

    1960-01-01

    Before the invention of wire chambers, particles tracks were analysed on scanning tables like this one. Today, the process is electronic and much faster. Bubble chamber film - currently available - (links can be found below) was used for this analysis of the particle tracks.

  16. Scan Statistics

    CERN Document Server

    Glaz, Joseph

    2009-01-01

    Suitable for graduate students and researchers in applied probability and statistics, as well as for scientists in biology, computer science, pharmaceutical science and medicine, this title brings together a collection of chapters illustrating the depth and diversity of theory, methods and applications in the area of scan statistics.

  17. Endoscopic medial maxillectomy breaking new frontiers.

    Science.gov (United States)

    Mohanty, Sanjeev; Gopinath, M

    2013-07-01

    Endoscopy has changed the perspective of rhinologist towards the nose. It has revolutionised the surgical management of sinonasal disorders. Sinus surgeries were the first to get the benefit of endoscope. Gradually the domain of endoscopic surgery extended to the management of sino nasal tumours. Traditionally medial maxillectomy was performed through lateral rhinotomy or mid facial degloving approach. Endoscopic medial maxillectomy has been advocated by a number of authors in the management of benign sino-nasal tumours. We present our experience of endoscopic medial maxillectomy in the management of sinonasal pathologies.

  18. Asymptomatic Esophageal Varices Should Be Endoscopically Treated

    Directory of Open Access Journals (Sweden)

    Nib Soehendra

    1998-01-01

    Full Text Available Endoscopic treatment has generally been accepted in the management of bleeding esophageal varices. Both the control of acute variceal bleeding and elective variceal eradication to prevent recurrent bleeding can be achieved via endoscopic methods. In contrast to acute and elective treatment, the role of endoscopic therapy in asymptomatic patients who have never had variceal bleeding remains controversial because of the rather disappointing results obtained from prophylactic sclerotherapy. Most published randomized controlled trials showed that prophylactic sclerotherapy had no effect on survival. In some studies, neither survival rate nor bleeding risk was improved. In this article, the author champions the view that asymptomatic esophageal varices should be endoscopically treated.

  19. Endoscopic full-thickness resection: Current status.

    Science.gov (United States)

    Schmidt, Arthur; Meier, Benjamin; Caca, Karel

    2015-08-21

    Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices.

  20. Image segmentation of pyramid style identifier based on Support Vector Machine for colorectal endoscopic images.

    Science.gov (United States)

    Okamoto, Takumi; Koide, Tetsushi; Sugi, Koki; Shimizu, Tatsuya; Anh-Tuan Hoang; Tamaki, Toru; Raytchev, Bisser; Kaneda, Kazufumi; Kominami, Yoko; Yoshida, Shigeto; Mieno, Hiroshi; Tanaka, Shinji

    2015-08-01

    With the increase of colorectal cancer patients in recent years, the needs of quantitative evaluation of colorectal cancer are increased, and the computer-aided diagnosis (CAD) system which supports doctor's diagnosis is essential. In this paper, a hardware design of type identification module in CAD system for colorectal endoscopic images with narrow band imaging (NBI) magnification is proposed for real-time processing of full high definition image (1920 × 1080 pixel). A pyramid style image segmentation with SVMs for multi-size scan windows, which can be implemented on an FPGA with small circuit area and achieve high accuracy, is proposed for actual complex colorectal endoscopic images.

  1. Endoscopic ultrasound-guided transmural drainage of postoperative pancreatic collections.

    Science.gov (United States)

    Tilara, Amy; Gerdes, Hans; Allen, Peter; Jarnagin, William; Kingham, Peter; Fong, Yuman; DeMatteo, Ronald; D'Angelica, Michael; Schattner, Mark

    2014-01-01

    Pancreatic leak is a major cause of morbidity after pancreatectomy. Traditionally, peripancreatic fluid collections have been managed by percutaneous or operative drainage. Data for endoscopic ultrasound (EUS)-guided drainage of postoperative fluid collections are limited. Here we report on the safety, efficacy, and timing of EUS-guided drainage of postoperative peripancreatic collections. This is a retrospective review of 31 patients who underwent EUS-guided drainage of fluid collections after pancreatic resection. Technical success was defined as successful transgastric deployment of at least one double pigtail plastic stent. Clinical success was defined as resolution of the fluid collection on follow-up CT scan and resolution of symptoms. Early drainage was defined as initial transmural stent placement within 30 days after surgery. Endoscopic ultrasound-guided drainage was performed effectively with a technical success rate of 100%. Clinical success was achieved in 29 of 31 patients (93%). Nineteen of the 29 patients (65%) had complete resolution of their symptoms and collection with the first endoscopic procedure. Repeat drainage procedures, including some with necrosectomy, were required in the remaining 10 patients, with eventual resolution of collection and symptoms. Two patients who did not achieve durable clinical success required percutaneous drainage by interventional radiology. Seventeen (55%) of 31 patients had successful early drainage completed within 30 days of their operation. Endoscopic ultrasound-guided drainage of fluid collections after pancreatic resection is safe and effective. Early drainage (collections was not associated with increased complications in this series. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Endoscopic endonasal trans-sphenoid surgery of pituitary adenoma

    Directory of Open Access Journals (Sweden)

    Y R Yadav

    2012-01-01

    Full Text Available Endoscopic endonasal trans-sphenoid surgery (EETS is increasingly used for pituitary lesions. Pre-operative CT and MRI scans and peroperative endoscopic visualization can provide useful anatomical information. EETS is indicated in sellar, suprasellar, intraventricular, retro-infundibular, and invasive tumors. Recurrent and residual lesions, pituitary apoplexy and empty sella syndrome can be managed by EETS. Modern neuronavigation techniques, ultrasonic aspirators, ultrasonic bone curette can add to the safety. The binostril approach provides a wider working area. High definition camera is much superior to three-chip camera. Most of the recent reports favor EETS in terms of safety, quality of life and tumor resection, hospital stay, better endocrinological, and visual outcome as compared to the microscopic technique. Nasal symptoms, blood loss, operating time are less in EETS. Various naso-septal flaps and other techniques of CSF leak repair could help reduce complications. Complications can be further reduced after achieving the learning curve, good understanding of limitations with proper patient selection. Use of neuronavigation, proper post-operative care of endocrine function, establishing pituitary center of excellence and more focused residency and endoscopic fellowship training could improve results. The faster and safe transition from microscopic to EETS can be done by the team concept of neurosurgeon/otolaryngologist, attending hands on cadaveric dissection, practice on models, and observation of live surgeries. Conversion to a microscopic or endoscopic-assisted approach may be required in selected patients. Multi-modality treatment could be required in giant and invasive tumors. EETS appears to be a better surgical option in most pituitary adenoma.

  3. Experimental research on continuous basalt fiber and basalt-fibers-reinforced polymers

    Science.gov (United States)

    Zhang, Xueyi; Zou, Guangping; Shen, Zhiqiang

    2008-11-01

    The interest for continuous basalt fibers and reinforced polymers has recently grown because of its low price and rich natural resource. Basalt fiber was one type of high performance inorganic fibers which were made from natural basalt by the method of melt extraction. This paper discusses basic mechanical properties of basalt fiber. The other work in this paper was to conduct tensile testing of continuous basalt fiber-reinforced polymer rod. Tensile strength and stress-strain curve were obtained in this testing. The strength of rod was fairly equal to rod of E-glass fibers and weaker than rod of carbon fibers. Surface of crack of rod was studied. An investigation of fracture mechanism between matrix and fiber was analyzed by SEM (Scanning electron microscopy) method. A poor adhesion between the matrix and fibers was also shown for composites analyzing SEM photos. The promising tensile properties of the presented basalt fibers composites have shown their great potential as alternative classical composites.

  4. Reprodutibilidade do exame de medida da camada de fibras nervosas da retina por meio da polarimetria de varredura a laser Reproducibility of retinal nerve fiber layer measurement by scanning laser polarimetry

    Directory of Open Access Journals (Sweden)

    Fernanda Bon Duarte

    1999-10-01

    ,02, nferior/temporal (p = 0,03 e temporal/nasal (p = 0,007 e superior/inferior (p = 0,037 e para as médias de espessura nos quadrantes inferior (p = 0,04 e temporal (p = 0,003. Conclusões: A análise dos dados indica ótima reprodutibilidade do exame intra-observador, e na avaliação inter-observador os melhores resultados de reprodutibilidade são obtidos quando a média das imagens fornecida pelo programa do equipamento é empregada.Purpose: To analyze the intra- and inter-observer reprodu-cibility of retinal fiber layer measurements. Methods: Twenty-six normal eyes underwent retinal nerve fiber layer thickness measurements with the GDx scanning system. Three images of each eye were taken by three different observers. For each case, each observer was asked to choose the best image and also to use the mean of the three images for each case. Comparisons were made using the best image and also the mean image provided by the software. The mean thickness values in each quadrant and their ratios were compared using Friedman rank analysis of variance. Results: The comparison of results obtained from the three images taken by the same observer (intraobserver reprodu-tibility did not show any statistically significant difference. The analysis of the data by the R (resident, T (technician and G (ophthalmologist specialized in glaucoma observers revealed respective-ly: pR( S = 0.89; I = 0.24; T = 0.89; N = 0.30, pT( S = 0.76; I = 0.70; T = 0.22; N = 0.63, and pG( S = 0.48; I = 0.89; T = 0.30; N = 0.89. Regarding the isolated values (superior, inferior, temporal and nasal, the analysis of the results considering the values obtained from the mean image did not reveal a statistically significant difference between the three investigators. But when relationships were considered a statistically significant difference was observed regarding the superior/inferior ratio (p S/I = 0.037. Statistically significant differences were detected when considering the best image. Inferior and

  5. Scanning holograms

    International Nuclear Information System (INIS)

    Natali, S.

    1984-01-01

    This chapter reports on the scanning of 1000 holograms taken in HOBC at CERN. Each hologram is triggered by an interaction in the chamber, the primary particles being pions at 340 GeV/c. The aim of the experiment is the study of charm production. The holograms, recorded on 50 mm film with the ''in line'' technique, can be analyzed by shining a parallel expanded laser beam through the film, obtaining immediately above it the real image of the chamber which can then be scanned and measured with a technique half way between emulsions and bubble chambers. The results indicate that holograms can be analyzed as quickly and reliably as in other visual techniques and that to them is open the same order of magnitude of large scale experiments

  6. Bone scans

    International Nuclear Information System (INIS)

    Hetherington, V.J.

    1989-01-01

    Oftentimes, in managing podiatric complaints, clinical and conventional radiographic techniques are insufficient in determining a patient's problem. This is especially true in the early stages of bone infection. Bone scanning or imaging can provide additional information in the diagnosis of the disorder. However, bone scans are not specific and must be correlated with clinical, radiographic, and laboratory evaluation. In other words, bone scanning does not provide the diagnosis but is an important bit of information aiding in the process of diagnosis. The more useful radionuclides in skeletal imaging are technetium phosphate complexes and gallium citrate. These compounds are administered intravenously and are detected at specific time intervals postinjection by a rectilinear scanner with minification is used and the entire skeleton can be imaged from head to toe. Minification allows visualization of the entire skeleton in a single image. A gamma camera can concentrate on an isolated area. However, it requires multiple views to complete the whole skeletal image. Recent advances have allowed computer augmentation of the data received from radionucleotide imaging. The purpose of this chapter is to present the current radionuclides clinically useful in podiatric patients

  7. Single-Blinded Prospective Implementation of a Preoperative Imaging Checklist for Endoscopic Sinus Surgery.

    Science.gov (United States)

    Error, Marc; Ashby, Shaelene; Orlandi, Richard R; Alt, Jeremiah A

    2018-01-01

    Objective To determine if the introduction of a systematic preoperative sinus computed tomography (CT) checklist improves identification of critical anatomic variations in sinus anatomy among patients undergoing endoscopic sinus surgery. Study Design Single-blinded prospective cohort study. Setting Tertiary care hospital. Subjects and Methods Otolaryngology residents were asked to identify critical surgical sinus anatomy on preoperative CT scans before and after introduction of a systematic approach to reviewing sinus CT scans. The percentage of correctly identified structures was documented and compared with a 2-sample t test. Results A total of 57 scans were reviewed: 28 preimplementation and 29 postimplementation. Implementation of the sinus CT checklist improved identification of critical sinus anatomy from 24% to 84% correct ( P identification of sinus anatomic variants, including those not directly included in the systematic review implemented. Conclusion The implementation of a preoperative endoscopic sinus surgery radiographic checklist improves identification of critical anatomic sinus variations in a training population.

  8. Robot-assisted endoscope guidance versus manual endoscope guidance in functional endonasal sinus surgery (FESS).

    Science.gov (United States)

    Eichhorn, Klaus Wolfgang; Westphal, Ralf; Rilk, Markus; Last, Carsten; Bootz, Friedrich; Wahl, Friedrich; Jakob, Mark; Send, Thorsten

    2017-10-01

    Having one hand occupied with the endoscope is the major disadvantage for the surgeon when it comes to functional endoscopic sinus surgery (FESS). Only the other hand is free to use the surgical instruments. Tiredness or frequent instrument changes can thus lead to shaky endoscopic images. We collected the pose data (position and orientation) of the rigid 0° endoscope and all the instruments used in 16 FESS procedures with manual endoscope guidance as well as robot-assisted endoscope guidance. In combination with the DICOM CT data, we tracked the endoscope poses and workspaces using self-developed tracking markers. All surgeries were performed once with the robot and once with the surgeon holding the endoscope. Looking at the durations required, we observed a decrease in the operating time because one surgeon doing all the procedures and so a learning curve occurred what we expected. The visual inspection of the specimens showed no damages to any of the structures outside the paranasal sinuses. Robot-assisted endoscope guidance in sinus surgery is possible. Further CT data, however, are desirable for the surgical analysis of a tracker-based navigation within the anatomic borders. Our marker-based tracking of the endoscope as well as the instruments makes an automated endoscope guidance feasible. On the subjective side, we see that RASS brings a relief for the surgeon.

  9. Diagnosis of recurrent gastric cancer at the surgical anastomosis with endoscopic US

    International Nuclear Information System (INIS)

    Lightdale, C.J.; Botet, J.F.; Brennan, M.F.; Coit, D.G.; Knapper, W.H.; Bains, M.S.

    1988-01-01

    Endoscopic US was used to examine 40 patients following resection of gastric cancer, all with CT scans negative for recurrence in the area of the surgical anastomosis. Endoscopic US was performed with the Olympus GF-UM2/EU-M2 7.5-MHz system. There were 24 patients proved by endoscopy (n = 18) or surgery (n = six) to have anastomotic recurrence and 16 without recurrence (follow-up, 6-11 months). Endoscopic US correctly identified 23 of 24 patients with anastomotic recurrence, with one false-negative study, and absence of recurrence in 13 of 16, with three false-positive studies. The sensitivity was 95%, the specificity 80%, the positive accuracy 88%, and the negative predictive accuracy 92%

  10. Endoscopic approach to the infratemporal fossa

    Directory of Open Access Journals (Sweden)

    Ahmed Youssef

    2014-06-01

    Conclusions: Endoscopic endonasal transpterygoid approach is considered one of the most useful surgical solutions to manage selected tumors that involve the infratemporal fossa. A good understanding of the endoscopic anatomy of infratemporal fossa allows safe and complete resection of lesions arising or extending to infratemporal fossa.

  11. Duodenal diverticular bleeding: an endoscopic challenge

    Directory of Open Access Journals (Sweden)

    Eduardo Valdivielso-Cortázar

    Full Text Available Duodenal diverticula are an uncommon cause of upper gastrointestinal bleeding. Until recently, it was primarily managed with surgery, but advances in the field of endoscopy have made management increasingly less invasive. We report a case of duodenal diverticular bleeding that was endoscopically managed, and review the literature about the various endoscopic therapies thus far described.

  12. Endoscopic palliation in gastric cancer

    International Nuclear Information System (INIS)

    Valdivieso, Eduardo

    2010-01-01

    The integral search for improved living conditions for those patients with gastric cancer who have not received curative surgical treatment continues to challenge the knowledge, dexterity and ethical foundations of medical teams. The justification for palliative treatment must be based on a thorough consideration of the available options and the particular situation in each case. This article reviews endoscopic therapy with auto expandable prosthetics for palliative treatment of gastric cancer, as well as the scientific evidence that supports its use and the factors that determine its indication.

  13. Integrated biophotonics in endoscopic oncology

    Science.gov (United States)

    Muguruma, Naoki; DaCosta, Ralph S.; Wilson, Brian C.; Marcon, Norman E.

    2009-02-01

    Gastrointestinal endoscopy has made great progress during last decade. Diagnostic accuracy can be enhanced by better training, improved dye-contrast techniques method, and the development of new image processing technologies. However, diagnosis using conventional endoscopy with white-light optical imaging is essentially limited by being based on morphological changes and/or visual attribution: hue, saturation and intensity, interpretation of which depends on the endoscopist's eye and brain. In microlesions in the gastrointestinal tract, we still rely ultimately on the histopathological diagnosis from biopsy specimens. Autofluorescence imaging system has been applied for lesions which have been difficult to morphologically recognize or are indistinct with conventional endoscope, and this approach has potential application for the diagnosis of dysplastic lesions and early cancers in the gastrointestinal tract, supplementing the information from white light endoscopy. This system has an advantage that it needs no administration of a photosensitive agent, making it suitable as a screening method for the early detection of neoplastic tissues. Narrow band imaging (NBI) is a novel endoscopic technique which can distinguish neoplastic and non-neoplastic lesions without chromoendoscopy. Magnifying endoscopy in combination with NBI has an obvious advantage, namely analysis of the epithelial pit pattern and the vascular network. This new technique allows a detailed visualization in early neoplastic lesions of esophagus, stomach and colon. However, problems remain; how to combine these technologies in an optimum diagnostic strategy, how to apply them into the algorithm for therapeutic decision-making, and how to standardize several classifications surrounding them. 'Molecular imaging' is a concept representing the most novel imaging methods in medicine, although the definition of the word is still controversial. In the field of gastrointestinal endoscopy, the future of

  14. Endoscopic optical coherence tomography with a focus-adjustable probe.

    Science.gov (United States)

    Liao, Wenchao; Chen, Tianyuan; Wang, Chengming; Zhang, Wenxin; Peng, Zhangkai; Zhang, Xiao; Ai, Shengnan; Fu, Deyong; Zhou, Tieying; Xue, Ping

    2017-10-15

    We present a focus-adjustable endoscopic probe for optical coherence tomography (OCT), which is able to acquire images with different focal planes and overcome depth-of-focus limitations by image fusing. The use of a two-way shape-memory-alloy spring enables the probe to adjust working distance over 1.5 mm, providing a large scanning range with high resolution and no sensitivity loss. Equipped with a homemade hollow-core ultrasonic motor, the probe is capable of performing an unobstructed 360 deg field-of-view distal scanning. Both the axial resolution and the best lateral resolution are ∼4  μm, with a sensitivity of 100.3 dB. Spectral-domain OCT imaging of phantom and biological tissues with the probe is also demonstrated.

  15. Endoscopic management of hilar biliary strictures

    Science.gov (United States)

    Singh, Rajiv Ranjan; Singh, Virendra

    2015-01-01

    Hilar biliary strictures are caused by various benign and malignant conditions. It is difficult to differentiate benign and malignant strictures. Postcholecystectomy benign biliary strictures are frequently encountered. Endoscopic management of these strictures is challenging. An endoscopic method has been advocated that involves placement of increasing number of stents at regular intervals to resolve the stricture. Malignant hilar strictures are mostly unresectable at the time of diagnosis and only palliation is possible.Endoscopic palliation is preferred over surgery or radiological intervention. Magnetic resonance cholangiopancreaticography is quite important in the management of these strictures. Metal stents are superior to plastic stents. The opinion is divided over the issue of unilateral or bilateral stenting.Minimal contrast or no contrast technique has been advocated during endoscopic retrograde cholangiopancreatography of these patients. The role of intraluminal brachytherapy, intraductal ablation devices, photodynamic therapy, and endoscopic ultrasound still remains to be defined. PMID:26191345

  16. Endoscopes with latest technology and concept.

    Science.gov (United States)

    Gotoh

    2003-09-01

    Endoscopic imaging systems that perform as the "eye" of the operator during endoscopic surgical procedures have developed rapidly due to various technological developments. In addition, since the most recent turn of the century robotic surgery has increased its scope through the utilization of systems such as Intuitive Surgical's da Vinci System. To optimize the imaging required for precise robotic surgery, a unique endoscope has been developed, consisting of both a two dimensional (2D) image optical system for wider observation of the entire surgical field, and a three dimensional (3D) image optical system for observation of the more precise details at the operative site. Additionally, a "near infrared radiation" endoscopic system is under development to detect the sentinel lymph node more readily. Such progress in the area of endoscopic imaging is expected to enhance the surgical procedure from both the patient's and the surgeon's point of view.

  17. Endoscopic findings following retroperitoneal pancreas transplantation.

    Science.gov (United States)

    Pinchuk, Alexey V; Dmitriev, Ilya V; Shmarina, Nonna V; Teterin, Yury S; Balkarov, Aslan G; Storozhev, Roman V; Anisimov, Yuri A; Gasanov, Ali M

    2017-07-01

    An evaluation of the efficacy of endoscopic methods for the diagnosis and correction of surgical and immunological complications after retroperitoneal pancreas transplantation. From October 2011 to March 2015, 27 patients underwent simultaneous retroperitoneal pancreas-kidney transplantation (SPKT). Diagnostic oesophagogastroduodenoscopy (EGD) with protocol biopsy of the donor and recipient duodenal mucosa and endoscopic retrograde pancreatography (ERP) were performed to detect possible complications. Endoscopic stenting of the main pancreatic duct with plastic stents and three-stage endoscopic hemostasis were conducted to correct the identified complications. Endoscopic methods showed high efficiency in the timely diagnosis and adequate correction of complications after retroperitoneal pancreas transplantation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Video: two novel endoscopic esophageal lengthening and reconstruction techniques.

    Science.gov (United States)

    Perretta, Silvana; Wall, James K; Dallemagne, Bernard; Harrison, Michael; Becmeur, François; Marescaux, Jacques

    2011-10-01

    Esophageal reconstruction presents a significant clinical challenge in patients ranging from neonates with long-gap esophageal atresia to adults after esophageal resection. Both gastric and colonic replacement conduits carry significant morbidity. As emerging organ-sparring techniques become established for early stage esophageal tumors, less morbid reconstruction techniques are warranted. We present two novel endoscopic approaches for esophageal lengthening and reconstruction in a porcine model. Two models of esophageal defects were created in pigs (30-35 kg) under general anesthesia and subsequently reconstructed with the novel techniques. The first model was a segmental defect of the esophagus created by thoracoscopically transecting the esophagus above the gastroesophageal (GE) junction. The first reconstruction technique involved bilateral submucosal endoscopic lengthening myotomies (BSELM) with a magnetic compression anastomosis (MAGNAMOSIS™). The second model was a wedge defect in the anterior esophagus created above the GE junction through a laparotomy. The second reconstruction technique involved an inverted mucosal-submucosal sleeve transposition graft (IMSTG) that crossed the esophageal gap and was secured in place with a self-expandable covered esophageal stent. Both techniques were feasible in the pig model. The BSELM approach lengthened the esophagus 1 cm for every 2 cm length of myotomy. The myotomy targeted only the inner circular fibers of the esophagus, with preservation of the longitudinal layer to protect against long-term dilation and pouching. The IMSTG approach generated a vascularized mucosal graft almost as long as the esophagus itself. Emerging endoscopic capabilities are enabling complex endoluminal esophageal procedures. BSELM and IMSTG are two novel and technically feasible approaches to esophageal lengthening and reconstruction. Further survival studies are needed to establish the safety and efficacy of these techniques.

  19. Fiber optic neutron imaging system: calibration

    International Nuclear Information System (INIS)

    Malone, R.M.; Gow, C.E.; Thayer, D.R.

    1981-01-01

    Two neutron imaging experiments using fiber optics have been performed at the Nevada Test Site. In each experiment, an array of scintillator fluor tubes is exposed to neutrons. Light is coupled out through radiation resistant PCS fibers (8-m long) into high-bandwidth, graded index fibers. For image reconstruction to be accurate, common timing differences and transmission variations between fiber optic channels are needed. The calibration system featured a scanning pulsed dye laser, a specially designed fiber optic star coupler, a tektronix 7912AD transient digitizer, and a DEC PDP 11/34 computing system

  20. Surgical Reimplantation for the Correction of Vesicoureteral Reflux following Failed Endoscopic Injection

    Directory of Open Access Journals (Sweden)

    Boris Chertin

    2011-01-01

    Full Text Available Purpose. In recent years, endoscopic injection became the procedure of choice for the correction of vesicoureteral reflux in the majority of the centers. Unfortunately, endoscopic treatment is not always successful and sometimes requires more than one trial to achieve similar results to that of an open reimplantation surgery. Our aim of this study is to evaluate the feasibility and success rate of open ureteral reimplantation following failed endoscopic procedure. Patients and Methods. During 2004–2010, we evaluated 16 patients with persistent vesicoureteral reflux (grades II–IV following failed endoscopic treatment. All patients underwent open ureteral reimplantation. All patients were followed with an ultrasound 6 weeks following surgery and every 6 months thereafter for an average of 22 months. Voiding cystography was performed at 3 months after surgery. Results. During unilateral open ureteral reimplantation, the implanted deposit from previous procedures was either excised, drained, or incorporated into the neotunnel with the ureter. Vesicoureteral reflux was resolved in all patients with 100% success rate. No new hydronephrosis or signs of obstruction developed in any of the patients. qDMSA renal scan was available in 8 patients showing improvement of function in 5 and stable function in 3, and no new scars were identified. Conclusions. Open ureteral reimplantation is an excellent choice for the correction of failed endoscopic treatment in children with vesicoureteral reflux.

  1. Successful Emergency Endoscopic Treatment of Gastric Outlet Obstruction due to Gastric Bezoar with Gastric Pneumatosis

    Directory of Open Access Journals (Sweden)

    Hirokazu Honda

    2017-11-01

    Full Text Available Gastric bezoars are rare and are usually found incidentally. They can sometimes cause severe complications, including gastric outlet obstruction (GOO or gastric pneumatosis (GP. In cases of bezoars with GP, the optimal treatment strategy has not yet been defined. We report the case of an 89-year-old man with a history of type 2 diabetes mellitus and hypertension who presented to our emergency room with a 2-day history of upper abdominal pain, nausea, and vomiting. Physical examination revealed no rebound tenderness or guarding, and laboratory values revealed no elevation of the serum lactate level. A computed tomography scan of the abdomen showed a dilated stomach with significant fluid collection, GOO, and GP due to a 42 × 40 mm mass composed of fat and air densities. Emergency esophagogastroduodenoscopy revealed two gastric bezoars, one of which was incarcerated in the pyloric region. We used various endoscopic devices to successfully break and remove the bezoars. We used endoscopic forceps and a water jet followed by an endoscopic snare to cut the bezoars into several pieces and remove them with an endoscopic net. Follow-up endoscopy confirmed that the gastric bezoar had been completely removed. As seen in this case, endoscopic treatment may be a safe and viable option for the extraction of gastric bezoars presenting with GOO and GP.

  2. Successful Emergency Endoscopic Treatment of Gastric Outlet Obstruction due to Gastric Bezoar with Gastric Pneumatosis.

    Science.gov (United States)

    Honda, Hirokazu; Ikeya, Takashi; Kashiwagi, Erika; Okada, Shuichi; Fukuda, Katsuyuki

    2017-01-01

    Gastric bezoars are rare and are usually found incidentally. They can sometimes cause severe complications, including gastric outlet obstruction (GOO) or gastric pneumatosis (GP). In cases of bezoars with GP, the optimal treatment strategy has not yet been defined. We report the case of an 89-year-old man with a history of type 2 diabetes mellitus and hypertension who presented to our emergency room with a 2-day history of upper abdominal pain, nausea, and vomiting. Physical examination revealed no rebound tenderness or guarding, and laboratory values revealed no elevation of the serum lactate level. A computed tomography scan of the abdomen showed a dilated stomach with significant fluid collection, GOO, and GP due to a 42 × 40 mm mass composed of fat and air densities. Emergency esophagogastroduodenoscopy revealed two gastric bezoars, one of which was incarcerated in the pyloric region. We used various endoscopic devices to successfully break and remove the bezoars. We used endoscopic forceps and a water jet followed by an endoscopic snare to cut the bezoars into several pieces and remove them with an endoscopic net. Follow-up endoscopy confirmed that the gastric bezoar had been completely removed. As seen in this case, endoscopic treatment may be a safe and viable option for the extraction of gastric bezoars presenting with GOO and GP.

  3. Successful Gastric Volvulus Reduction and Gastropexy Using a Dual Endoscope Technique

    Directory of Open Access Journals (Sweden)

    Laith H. Jamil

    2014-01-01

    Full Text Available Gastric volvulus is a life threatening condition characterized by an abnormal rotation of the stomach around an axis. Although the first line treatment of this disorder is surgical, we report here a case of gastric volvulus that was endoscopically managed using a novel strategy. An 83-year-old female with a history of pancreatic cancer status postpylorus-preserving Whipple procedure presented with a cecal volvulus requiring right hemicolectomy. Postoperative imaging included a CT scan and upper GI series that showed a gastric volvulus with the antrum located above the diaphragm. An upper endoscopy was advanced through the pylorus into the duodenum and left in this position to keep the stomach under the diaphragm. A second pediatric endoscope was advanced alongside and used to complete percutaneous endoscopic gastrostomy (PEG placement for anterior gastropexy. The patient’s volvulus resolved and there were no complications. From our review of the literature, the dual endoscopic technique employed here has not been previously described. Patients who are poor surgical candidates or those who do not require emergent surgery can possibly benefit the most from similar minimally invasive endoscopic procedures as described here.

  4. Conjugation of fiber-coupled wide-band light sources and acousto-optical spectral elements

    Science.gov (United States)

    Machikhin, Alexander; Batshev, Vladislav; Polschikova, Olga; Khokhlov, Demid; Pozhar, Vitold; Gorevoy, Alexey

    2017-12-01

    Endoscopic instrumentation is widely used for diagnostics and surgery. The imaging systems, which provide the hyperspectral information of the tissues accessible by endoscopes, are particularly interesting and promising for in vivo photoluminescence diagnostics and therapy of tumour and inflammatory diseases. To add the spectral imaging feature to standard video endoscopes, we propose to implement acousto-optical (AO) filtration of wide-band illumination of incandescent-lamp-based light sources. To collect maximum light and direct it to the fiber-optic light guide inside the endoscopic probe, we have developed and tested the optical system for coupling the light source, the acousto-optical tunable filter (AOTF) and the light guide. The system is compact and compatible with the standard endoscopic components.

  5. Development of an integrated filing system for endoscopic images.

    Science.gov (United States)

    Fujino, M A; Ikeda, M; Yamamoto, Y; Kinose, T; Tachikawa, H; Morozumi, A; Sano, S; Kojima, Y; Nakamura, T; Kawai, T

    1991-01-01

    A new integrated filing system for endoscopic images has been developed, comprising a main image filing system and subsystems located at different stations. A hybrid filing system made up of both digital and analog filing devices was introduced to construct this system that combines the merits of the two filing methods. Each subsystem provided with a video processor, is equipped with a digital filing device, and routine images were recorded in the analog image filing device of the main system. The use of a multi-input adapter enabled simultaneous input of analog images from up to 8 video processors. Recorded magneto-optical disks make it possible to recall the digital images at any station in the hospital; the disks are copied without image degradation and also utilised for image processing. This system promises reliable storage and integrated, efficient management of endoscopic information. It also costs less to install than the so-called PACS (picture archiving and communication system), which connects all the stations of the hospital using optical fiber cables.

  6. Endoscopic diode laser therapy for chronic radiation proctitis.

    Science.gov (United States)

    Polese, Lino; Marini, Lucia; Rizzato, Roberto; Picardi, Edgardo; Merigliano, Stefano

    2018-01-01

    The purpose of this study is to determine the effectiveness of endoscopic diode laser therapy in patients presenting rectal bleeding due to chronic radiation proctitis (CRP). A retrospective analysis of CRP patients who underwent diode laser therapy in a single institution between 2010 and 2016 was carried out. The patients were treated by non-contact fibers without sedation in an outpatient setting. Fourteen patients (median age 77, range 73-87 years) diagnosed with CRP who had undergone high-dose radiotherapy for prostatic cancer and who presented with rectal bleeding were included. Six required blood transfusions. Antiplatelet (three patients) and anticoagulant (two patients) therapy was not suspended during the treatments. The patients underwent a median of two sessions; overall, a mean of 1684 J of laser energy per session was used. Bleeding was resolved in 10/14 (71%) patients, and other two patients showed improvement (93%). Only one patient, who did not complete the treatment, required blood transfusions after laser therapy; no complications were noted during or after the procedures. Study findings demonstrated that endoscopic non-contact diode laser treatment is safe and effective in CRP patients, even in those receiving antiplatelet and/or anticoagulant therapy.

  7. Therapeutic aspects of endoscopic ultrasound

    Science.gov (United States)

    Woodward, Timothy A.

    1999-06-01

    Endoscopic ultrasound (EUS) is a technology that had been used primarily as a passive imaging modality. Recent advances have enabled us to move beyond the use of EUS solely as a staging tool to an interventional device. Current studies suggest that interventional applications of EUS will allow for minimally invasive assessment and therapies in a cost-effective manner. Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has been demonstrated to be a technically feasible, relatively safe method of obtaining cytologic specimens. The clinical utility of EUS- FNA appears to be greatest in the diagnosis and staging of pancreatic cancer and in the nodal staging of gastrointestinal and pulmonary malignancies. In addition, EUS-FNA has demonstrated utility in the sampling pleural and ascitic fluid not generally appreciated or assessable to standard interventions. Interventional applications of EUS include EUS-guided pseudocyst drainage, EUS-guided injection of botulinum toxin in the treatment of achalasia, and EUS- guided celiac plexus neurolysis in the treatment of pancreatic cancer pain. Finally, EUS-guided fine-needle installation is being evaluated, in conjunction with recent bimolecular treatment modalities, as a delivery system in the treatment of certain gastrointestinal tumors.

  8. Endoscopic Transsphenoidal Resection of Craniopharyngioma.

    Science.gov (United States)

    Liew, Kong Yew; Narayanan, Prepageran; Waran, Vicknes

    2018-02-01

    Objectives  To demonstrate, step-by-step, the technique and efficacy of endoscopic transsphenoidal approach in resection of a suprasellar craniopharyngioma. Design  The video shows a step-by-step approach to the resection, covering the exposure, access, resection, and confirmation of resection and reconstruction. Setting  The surgery was performed in the University of Malaya Medical Centre, a tertiary referral center in the capital of Malaysia. Participants  Surgery was performed jointly by Professor Prepageran from the department of otorhinolaryngology and Professor Vicknes Waran from the division of neurosurgery. Both surgeons are from the University of Malaya. Video compilation, editing, and voice narration was done by Dr. Kong Yew Liew. Main Outcome Measures  Completeness of resection and avoidance of intra- and postoperative complications. Results  Based on intraoperative views and MRI findings, the tumor was completely resected with the patient suffering only transient diabetes insipidus. Conclusion  Central suprasellar tumors can be removed completely via an endoscopic transsphenoidal approach with minimal morbidity to the patient. The link to the video can be found at: https://youtu.be/ZNIHfk12cYg .

  9. 21 CFR 884.4100 - Endoscopic electrocautery and accessories.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Endoscopic electrocautery and accessories. 884... Surgical Devices § 884.4100 Endoscopic electrocautery and accessories. (a) Identification. An endoscopic electrocautery is a device used to perform female sterilization under endoscopic observation. It is designed to...

  10. Fiber tracking for brain tumor

    International Nuclear Information System (INIS)

    Yamada, Kei; Nakamura, Hisao; Ito, Hirotoshi; Tanaka, Osamu; Kubota, Takao; Yuen, Sachiko; Kizu, Osamu; Nishimura, Tsunehiko

    2003-01-01

    The purpose of this study was to validate an innovative scanning method for patients diagnosed with brain tumors. Using a 1.5 Tesla whole body magnetic resonance (MR) imager, 23 patients with brain tumors were scanned. The recorded data points of the diffusion-tensor imaging (DTI) sequences were 128 x 37 with the parallel imaging technique. The parallel imaging technique was equivalent to a true resolution of 128 x 74. The scan parameters were repetition time (TR)=6000, echo time (TE)=88, 6 averaging with a b-value of 800 s/mm 2 . The total scan time for DTI was 4 minutes and 24 seconds. DTI scans and subsequent fiber tracking were successfully applied in all cases. All fiber tracts on the contralesional side were visualized in the expected locations. Fiber tracts on the lesional side had varying degrees of displacement, disruption, or a combination of displacement and disruption due to the tumor. Tract disruption resulted from direct tumor involvement, compression upon the tract, and vasogenic edema surrounding the tumor. This DTI method using a parallel imaging technique allows for clinically feasible fiber tracking that can be incorporated into a routine MR examination. (author)

  11. Endoscopic approaches to treatment of achalasia

    Science.gov (United States)

    Friedel, David; Modayil, Rani; Iqbal, Shahzad; Grendell, James H.

    2013-01-01

    Endoscopic therapy for achalasia is directed at disrupting or weakening the lower esophageal sphincter (LES). The two most commonly utilized endoscopic interventions are large balloon pneumatic dilation (PD) and botulinum toxin injection (BTI). These interventions have been extensively scrutinized and compared with each other as well as with surgical disruption (myotomy) of the LES. PD is generally more effective in improving dysphagia in achalasia than BTI, with the latter reserved for infirm older people, and PD may approach treatment results attained with myotomy. However, PD may need to be repeated. Small balloon dilation and endoscopic stent placement for achalasia have only been used in select centers. Per oral endoscopic myotomy is a newer endoscopic modality that will likely change the treatment paradigm for achalasia. It arose from the field of natural orifice transluminal endoscopic surgery and represents a scarless endoscopic approach to Heller myotomy. This is a technique that requires extensive training and preparation and thus there should be rigorous accreditation and monitoring of outcomes to ensure safety and efficacy. PMID:23503707

  12. Endoscopic management of bleeding peptic ulcers

    International Nuclear Information System (INIS)

    Farooqi, J.I.; Farooqi, R.J.

    2001-01-01

    Peptic ulcers account for more than half of the cases of non variceal upper gastrointestinal (GI) bleeding and therefore, are the focus of most of the methods of endoscopic hemostasis. Surgical intervention is now largely reserved for patients in whom endoscopic hemostasis has failed. A variety of endoscopic techniques have been employed to stop bleeding and reduce the risk of rebleeding, with no major differences in outcome between these methods. These include injection therapy, fibrin injection, heater probe, mono polar electrocautery, bipolar electrocautery, lasers and mechanical hemo clipping. The most important factor in determining outcome after gastrointestinal bleeding is rebleeding or persistent bleeding. The endoscopic appearance of an ulcer, however, provides the most useful prognostic information for bleeding. Recurrent bleeding after initial endoscopic hemostasis occurs in 15-20% of patients with a bleeding peptic ulcer. The best approach to these patients remains controversial; the current options are repeat endoscopic therapy with the same or a different technique, emergency surgery or semi elective surgery after repeat endoscopic hemostasis. The combination of epinephrine injection with thermal coagulation may be more effective than epinephrine injection alone. Newer modalities such as fibrin injection or the application of hemo clips appear promising and comparative studies are awaited. (author)

  13. [PACS-based endoscope image acquisition workstation].

    Science.gov (United States)

    Liu, J B; Zhuang, T G

    2001-01-01

    A practical PACS-based Endoscope Image Acquisition Workstation is here introduced. By a Multimedia Video Card, the endoscope video is digitized and captured dynamically or statically into computer. This workstation realizes a variety of functions such as the endoscope video's acquisition and display, as well as the editing, processing, managing, storage, printing, communication of related information. Together with other medical image workstation, it can make up the image sources of PACS for hospitals. In addition, it can also act as an independent endoscopy diagnostic system.

  14. Clinical endoscopic management and outcome of post-endoscopic sphincterotomy bleeding.

    Directory of Open Access Journals (Sweden)

    Wei-Chen Lin

    Full Text Available Post-endoscopic sphincterotomy bleeding is a common complication of biliary sphincterotomy, and the incidence varies from 1% to 48%. It can be challenging to localize the bleeder or to administer various interventions through a side-viewing endoscope. This study aimed to evaluate the risk factors of post-endoscopic sphincterotomy bleeding and the outcome of endoscopic intervention therapies. We retrospectively reviewed the records of 513 patients who underwent biliary sphincterotomy in Mackay Memorial Hospital between 2011 and 2016. The blood biochemistry, comorbidities, indication for sphincterotomy, severity of bleeding, endoscopic features of bleeder, and type of endoscopic therapy were analyzed. Post-endoscopic sphincterotomy bleeding occurred in 65 (12.6% patients. Forty-five patients had immediate bleeding and 20 patients had delayed bleeding. The multivariate analysis of risk factors associated with post-endoscopic sphincterotomy bleeding were liver cirrhosis (P = 0.029, end-stage renal disease (P = 0.038, previous antiplatelet drug use (P<0.001, and duodenal ulcer (P = 0.023. The complications of pancreatitis and cholangitis were higher in the bleeding group, with statistical significance. Delayed bleeding occurred within 1 to 7 days (mean, 2.5 days, and 60% (12/20 of the patients received endoscopic evaluation. In the delayed bleeding group, the successful hemostasis rate was 71.4% (5/7, and 65% (13/20 of the patients had ceased bleeding without endoscopic hemostasis therapy. Comparison of different therapeutic modalities showed that cholangitis was higher in patients who received epinephrine spray (P = 0.042 and pancreatitis was higher in patients who received epinephrine injection and electrocoagulation (P = 0.041 and P = 0.039 respectively. Clinically, post-endoscopic sphincterotomy bleeding and further endoscopic hemostasis therapy increase the complication rate of pancreatitis and cholangitis. Realizing the effectiveness of each

  15. An algorithm for improving the quality of structural images of turbid media in endoscopic optical coherence tomography

    Science.gov (United States)

    Potlov, A. Yu.; Frolov, S. V.; Proskurin, S. G.

    2018-04-01

    High-quality OCT structural images reconstruction algorithm for endoscopic optical coherence tomography of biological tissue is described. The key features of the presented algorithm are: (1) raster scanning and averaging of adjacent Ascans and pixels; (2) speckle level minimization. The described algorithm can be used in the gastroenterology, urology, gynecology, otorhinolaryngology for mucous membranes and skin diagnostics in vivo and in situ.

  16. [Prediction of the efficiency of endoscopic lung volume reduction by valves in severe emphysema].

    Science.gov (United States)

    Bocquillon, V; Briault, A; Reymond, E; Arbib, F; Jankowski, A; Ferretti, G; Pison, C

    2016-11-01

    In severe emphysema, endoscopic lung volume reduction with valves is an alternative to surgery with less morbidity and mortality. In 2015, selection of patients who will respond to this technique is based on emphysema heterogeneity, a complete fissure visible on the CT-scan and absence of collateral ventilation between lobes. Our case report highlights that individualized prediction is possible. A 58-year-old woman had severe, disabling pulmonary emphysema. A high resolution thoracic computed tomography scan showed that the emphysema was heterogeneous, predominantly in the upper lobes, integrity of the left greater fissure and no collateral ventilation with the left lower lobe. A valve was inserted in the left upper lobe bronchus. At one year, clinical and functional benefits were significant with complete atelectasis of the treated lobe. The success of endoscopic lung volume reduction with a valve can be predicted, an example of personalized medicine. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  17. Defining the Limits of Endoscopic Access to Internal Auditory Canal.

    Science.gov (United States)

    Master, Adam; Hamiter, Mickie; Cosetti, Maura

    2016-12-01

    To quantify surgical access to the internal auditory canal (IAC) using an exclusively endoscopic transcanal approach (EETA) and investigate surgically relevant relationships with neurovascular and osseous landmarks of the temporal bone. Anatomical dissection of two paired temporal bones and 15 unpaired temporal bones was performed using an exclusively endoscopic approach to IAC. The dissection proceeded until the cerebellopontine angle (CPA) could be accessed. Following dissection, all the specimens were subjected to computed tomography (CT) imaging. Anatomage InVivo5 software was used to analyze the CT scans and record measurements. CPA access and visualization of the labyrinthine segment of the facial nerve were achieved in all specimens. The mean distances from the carotid artery, jugular bulb, and middle fossa to the surgical opening (or fundostomy) of IAC were 4.1±1.5, 6.4±2.5, and 5.5±1.9 mm, respectively. The mean cross-sectional areas of the fundostomy and tympanic ring were 30.8±10.4 and 67.7±11.3 mm2. The mean distances from the osteo-cartilaginous junction and tympanic ring to the porus acusticus were 29±2.6 and 21±2.3 mm, respectively. Transcanal access to the entire IAC can be safely achieved using an exclusively endoscopic approach. Generous removal of the cochlear promontory can be accomplished while a safe distance is maintained from key neurovascular structures. EETA to IAC offers a minimally invasive alternative to patients without serviceable hearing for intrameatal and medial IAC tumors. Increased knowledge of crucial anatomical relationships involved in this approach will facilitate acceptance and utilization.

  18. Nanofibers extraction from palm mesocarp fiber for biodegradable polymers incorporation

    International Nuclear Information System (INIS)

    Kuana, Vanessa A.; Rodrigues, Vanessa B.; Takahashi, Marcio C.; Campos, Adriana de; Sena Neto, Alfredo R.; Mattoso, Luiz H.C.; Marconcini, Jose M.

    2015-01-01

    The palm mesocarp fibers are residues produced by the palm oil industries. The objective of this paper is to determine an efficient treatment to extract crystal cellulose nanofibers from the palm mesocarp fibers to be incorporated in biodegradable polymeric composites. The fibers were saponified, bleached and analyzed with thermal gravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. (author)

  19. Cholangiography and endoscopic sphincterotomy in the ...

    African Journals Online (AJOL)

    Cholangiography and endoscopic sphincterotomy in the management of severe acute gallstone pancreatitis discovered at diag~osticlaparotomy. ... in these cases Included cholecystectomy and Ttube drainage (2 patients) cholecystostomy drainage (3 patients), and closure of the abdomen without drainage (2 patients).

  20. Endoscopic appearance of irradiated gastric mucosa

    Energy Technology Data Exchange (ETDEWEB)

    De Sagher, L I; Van den Heule, B; Van Houtte, P; Engelholm, L; Balikdjan, D; Bleiberg, H

    1979-09-01

    Irradiation of the epigastric area for gastric cancer may induce actinic lesions of the stomach characterized on endoscopic examination by ulcerations, haemorrhagic gastritis, fragility of the mucosa, thickening and congestion of the gastric folds.

  1. Endoscopic third ventriculostomy versus ventriculoperitoneal shunt ...

    African Journals Online (AJOL)

    Patients' medical records, operative notes, and neural tube database records were used to complete a structured questionnaire. The difference in ... likely after 6 months. Keywords: obstructive hydrocephalus; endoscopic third ventriculostomy; ventriculoperitoneal shunt; children; paediatric surgery; neurosurgery; Ethiopia ...

  2. Endoscopic versus external approach dacryocystorhinostomy: A ...

    African Journals Online (AJOL)

    Endoscopic versus external approach dacryocystorhinostomy: A comparative analysis. Rinki Saha, Anuradha Sinha, Jyoti Prakash Phukan. Abstract. Background: Dacryocystorhinostomy (DCR) consists of creating a lacrimal drainage pathway to the nasal cavity to restore permanent drainage of previously obstructed ...

  3. Diagnosis and management of iatrogenic endoscopic perforations

    DEFF Research Database (Denmark)

    Paspatis, Gregorios A; Dumonceau, Jean-Marc; Barthet, Marc

    2014-01-01

    This Position Paper is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the diagnosis and management of iatrogenic perforation occurring during diagnostic or therapeutic digestive endoscopic procedures. Main recommendations 1 ESGE recommends that ea...

  4. PULMONARY HEMORRHAGE. ENDOSCOPIC DIAGNOSIS AND TREATMENT

    Directory of Open Access Journals (Sweden)

    A. M. Gasanov

    2016-01-01

    Full Text Available In the article, we report the incidence and etiology of pulmonary hemorrhage, and modern classifications according to the literature data. Methods of endoscopic diagnosis and treatment of pulmonary hemorrhage are analyzed.

  5. Head CT scan

    Science.gov (United States)

    ... scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... head size in children Changes in thinking or behavior Fainting Headache, when you have certain other signs ...

  6. 3D handheld endoscope for optical coherence tomography of the human oral mucosa in vivo

    Science.gov (United States)

    Walther, Julia; Schnabel, Christian; Ebert, Nadja; Baumann, Michael; Koch, Edmund

    2017-07-01

    The early non-invasive diagnosis of epithelial tissue alterations in daily clinical routine is still challenging. Since optical coherence tomography (OCT) shows the potential to differentiate between benign and malignant tissue of primal endothelium, OCT could be beneficial for the early diagnosis of malignancies in routine health checks. In this research, a new handheld endoscopic scanning unit was designed and connected to a spectral domain OCT system of our workgroup for the in vivo imaging of the human oral mucosa.

  7. An unusual experience with endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Mallikarjun Patil

    2013-01-01

    Full Text Available The endoscopic retrograde cholangiopancreatography (ERCP is known for its varied diagnostic and therapeutic utility for a variety of disorders. However it has greater likelihood of procedure related complications among the endoscopic procedures of gastrointestinal tract. The extraluminal hemorrhagic complications following ERCP are potentially life threatening though relatively rare. We present a 50 year patient with choledocholithiasis and cholelithiasis developing rare complication of subcapsular hepatic hematoma, following ERCP due to guide wire injury.

  8. Importance of radiographic monitoring of endoscopic sphincterotomy

    International Nuclear Information System (INIS)

    Greenberg, H.M.; Goldberg, H.I.; Shapiro, H.A.

    1981-01-01

    The radiographic features of endoscopic sphincterotomies performed in 44 patients were evaluated. Radiographic landmarks aided in proper sphincterotome placement and also disclosed conditions and anatomic variations that made catheter placement difficult. Fluoroscopic and radiographic monitoring not only assisted the performance of endoscopic sphincterotomy, but also confirmed successful results and revealed reasons for failure. Radiographic changes in the biliary tract after sphincterotomy, as well as potential complications of sphincterotomy, are discussed and illustrated

  9. Two Fiber Optical Fiber Thermometry

    Science.gov (United States)

    Jones, Mathew R.; Farmer, Jeffery T.; Breeding, Shawn P.

    2000-01-01

    An optical fiber thermometer consists of an optical fiber whose sensing tip is given a metallic coating. The sensing tip of the fiber is essentially an isothermal cavity, so the emission from this cavity will be approximately equal to the emission from a blackbody. Temperature readings are obtained by measuring the spectral radiative heat flux at the end of the fiber at two wavelengths. The ratio of these measurements and Planck's Law are used to infer the temperature at the sensing tip. Optical fiber thermometers have high accuracy, excellent long-term stability and are immune to electromagnetic interference. In addition, they can be operated for extended periods without requiring re-calibration. For these reasons. it is desirable to use optical fiber thermometers in environments such as the International Space Station. However, it has recently been shown that temperature readings are corrupted by emission from the fiber when extended portions of the probe are exposed to elevated temperatures. This paper will describe several ways in which the reading from a second fiber can be used to correct the corrupted temperature measurements. The accuracy and sensitivity to measurement uncertainty will be presented for each method.

  10. Using external magnet guidance and endoscopically placed magnets to create suture-free gastro-enteral anastomoses.

    Science.gov (United States)

    Myers, Christopher; Yellen, Benjamin; Evans, John; DeMaria, Eric; Pryor, Aurora

    2010-05-01

    To facilitate endolumenal and natural orifice procedures, this study evaluated a novel technique using external and endoscopically placed magnets to create suture-free gastroenteral anastomoses. Seven anesthetized adult swine underwent endoscopic placement of magnets into the small bowel and stomach. Using external magnets, the endoscopically placed internal magnets were brought into opposition under endoscopic view. After 1-2 weeks, the pigs were killed and analyzed. At laparotomy and under sterile conditions, peritoneal cultures were obtained. The anastomoses were evaluated endoscopically and tested using an air insufflation test. Finally, the anastomoses were resected and evaluated microscopically. The average operative time for endoscopic placement of the magnets was 34.3 +/- 14.8 min. Successful placement and creation of anastomoses occurred in six of the pigs. One pig did not form an anastomosis because the magnets were too large to pass through the pylorus at the time of attempted magnet placement. Six swine experienced uncomplicated postoperative courses. One pig's postoperative course involved constipation for several days, requiring additional fluids and fiber supplementation. The findings at endoscopy showed that the magnets were adhered to the anastomosis, which were easily freed, or within the stomach. The air insufflation test results were negative for all the pigs. At laparotomy, there was no evidence of infection, abscess, or leak, but two peritoneal culture results were positive with scant growth of Staphylococcus aureus and coagulase-negative staphylococcus, presumably contaminants. Microscopically, the anastomoses illustrated granulation and fibrous connective tissue without evidence of infection or leak. Endoscopically placed magnets with external magnet guidance is a feasible and novel approach to creating patent gastroenteral anastomoses without abdominal incisions or sutures.

  11. Transanal endoscopic microsurgery versus endoscopic mucosal resection for large rectal adenomas (TREND-study)

    NARCIS (Netherlands)

    F.J.C. van den Broek (Frank); E.J.R. de Graaf (Eelco); M.G.W. Dijkgraaf (Marcel); J.B. Reitsma (Johannes); J. Haringsma (Jelle); R. Timmer (Robin); B.L. Weusten (Bas); M.F. Gerhards (Michael); E.C. Consten (Esther); M.P. Schwartz (Matthijs); M.J. Boom (Maarten); E.J. Derksen (Erik); A.B. Bijnen (Bart); P.H.P. Davids (Paul); C. Hoff (Christiaan); H.M. van Dullemen (Hendrik); G.D.N. Heine (Dimitri); K. van der Linde (Klaas); J.M. Jansen (Jeroen); R.C.H. Mallant-Hent (Rosalie); R. Breumelhof (Ronald); H. Geldof (Han); J.C. Hardwick (James); P. Doornebosch (Pascal); A.C.T.M. Depla (Annekatrien); M.F. Ernst (Miranda); I.P. van Munster (Ivo); I.H.J.T. de Hingh (Ignace); E.J. Schoon (Erik); W.A. Bemelman (Willem); P. Fockens (Paul); E. Dekker (Evelien)

    2009-01-01

    textabstractBackground: Recent non-randomized studies suggest that extended endoscopic mucosal resection (EMR) is equally effective in removing large rectal adenomas as transanal endoscopic microsurgery (TEM). If equally effective, EMR might be a more cost-effective approach as this strategy does

  12. Transanal endoscopic microsurgery versus endoscopic mucosal resection for large rectal adenomas (TREND-study)

    NARCIS (Netherlands)

    van den Broek, Frank J. C.; de Graaf, Eelco J. R.; Dijkgraaf, Marcel G. W.; Haringsma, Jelle; Timmer, Robin; Weusten, Bas L. A. M.; Gerhards, Michael F.; Consten, Esther C. J.; Schwartz, Matthijs P.; Boom, Maarten J.; Derksen, Erik J.; Bijnen, A. Bart; Davids, Paul H. P.; Hoff, Christiaan; van Dullemen, Hendrik M.; Heine, G. Dimitri N.; van der Linde, Klaas; Jansen, Jeroen M.; Mallant-Hent, Rosalie C. H.; Breumelhof, Ronald; Geldof, Han; Hardwick, James C. H.; Doornebosch, Pascal G.; Depla, Annekatrien C. T. M.; Ernst, Miranda F.; van Munster, Ivo P.; de Hingh, Ignace H. J. T.; Schoon, Erik J.; Bemelman, Willem A.; Fockens, Paul; Dekker, Evelien; Reitsma, J.

    2009-01-01

    Background: Recent non-randomized studies suggest that extended endoscopic mucosal resection (EMR) is equally effective in removing large rectal adenomas as transanal endoscopic microsurgery (TEM). If equally effective, EMR might be a more cost-effective approach as this strategy does not require

  13. Foot-controlled robotic-enabled endoscope holder for endoscopic sinus surgery: A cadaveric feasibility study.

    Science.gov (United States)

    Chan, Jason Y K; Leung, Iris; Navarro-Alarcon, David; Lin, Weiyang; Li, Peng; Lee, Dennis L Y; Liu, Yun-hui; Tong, Michael C F

    2016-03-01

    To evaluate the feasibility of a unique prototype foot-controlled robotic-enabled endoscope holder (FREE) in functional endoscopic sinus surgery. Cadaveric study. Using human cadavers, we investigated the feasibility, advantages, and disadvantages of the robotic endoscope holder in performing endoscopic sinus surgery with two hands in five cadaver heads, mimicking a single nostril three-handed technique. The FREE robot is relatively easy to use. Setup was quick, taking less than 3 minutes from docking the robot at the head of the bed to visualizing the middle meatus. The unit is also relatively small, takes up little space, and currently has four degrees of freedom. The learning curve for using the foot control was short. The use of both hands was not hindered by the presence of the endoscope in the nasal cavity. The tremor filtration also aided in the smooth movement of the endoscope, with minimal collisions. The FREE endoscope holder in an ex-vivo cadaver test corroborated the feasibility of the robotic prototype, which allows for a two-handed approach to surgery equal to a single nostril three-handed technique without the holder that may reduce operating time. Further studies will be needed to evaluate its safety profile and use in other areas of endoscopic surgery. NA. Laryngoscope, 126:566-569, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  14. Electron emission mechanism of carbon fiber cathode

    International Nuclear Information System (INIS)

    Liu Lie; Li Limin; Wen Jianchun; Wan Hong

    2005-01-01

    Models of electron emission mechanism are established concerning metal and carbon fiber cathodes. Correctness of the electron emission mechanism was proved according to micro-photos and electron scanning photos of cathodes respectively. The experimental results and analysis show that the surface flashover induces the electron emission of carbon fiber cathode and there are electron emission phenomena from the top of the carbon and also from its side surface. In addition, compared with the case of the stainless steel cathode, the plasma expansion velocity for the carbon fiber cathode is slower and the pulse duration of output microwave can be widened by using the carbon fiber cathode. (authors)

  15. Carbon Fiber Damage in Accelerator Beam

    CERN Document Server

    Sapinski, M; Guerrero, A; Koopman, J; Métral, E

    2009-01-01

    Carbon fibers are commonly used as moving targets in Beam Wire Scanners. Because of their thermomechanical properties they are very resistant to particle beams. Their strength deteriorates with time due to radiation damage and low-cycle thermal fatigue. In case of high intensity beams this process can accelerate and in extreme cases the fiber is damaged during a single scan. In this work a model describing the fiber temperature, thermionic emission and sublimation is discussed. Results are compared with fiber damage test performed on SPS beam in November 2008. In conclusions the limits of Wire Scanner operation on high intensity beams are drawn.

  16. Deposition of carbon nanotubes onto aramid fibers using as-received and chemically modified fibers

    International Nuclear Information System (INIS)

    Rodríguez-Uicab, O.; Avilés, F.; Gonzalez-Chi, P.I; Canché-Escamilla, G.; Duarte-Aranda, S.; Yazdani-Pedram, M.; Toro, P.; Gamboa, F.; Mazo, M.A.; Nistal, A.; Rubio, J.

    2016-01-01

    Highlights: • The surface of aramid fibers was functionalized by two acid treatments. • The treatment based on HNO_3/H_2SO_4 reduced the mechanical properties of the fibers. • CNTs were deposited on the aramid fibers, reaching electrical conductivity. • Homogeneous CNT distribution was achieved by using pristine fibers or chlorosulfonic acid. - Abstract: Multiwall carbon nanotubes (MWCNTs) oxidized by an acid treatment were deposited on the surface of as-received commercial aramid fibers containing a surface coating (“sizing”), and fibers modified by either a chlorosulfonic treatment or a mixture of nitric and sulfuric acids. The surface of the aramid fiber activated by the chemical treatments presents increasing density of CO, COOH and OH functional groups. However, these chemical treatments reduced the tensile mechanical properties of the fibers, especially when the nitric and sulfuric acid mixture was used. Characterization of the MWCNTs deposited on the fiber surface was conducted by scanning electron microscopy, Raman spectroscopy mapping and X-ray photoelectron spectroscopy. These characterizations showed higher areal concentration and more homogeneous distribution of MWCNTs over the aramid fibers for as-received fibers and for those modified with chlorosulfonic acid, suggesting the existence of interaction between the oxidized MWCNTs and the fiber coating. The electrical resistance of the MWCNT-modified aramid yarns comprising ∼1000 individual fibers was in the order of MΩ/cm, which renders multifunctional properties.

  17. Deposition of carbon nanotubes onto aramid fibers using as-received and chemically modified fibers

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez-Uicab, O. [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburna de Hidalgo, C.P. 97200 Mérida, Yucatán (Mexico); Avilés, F., E-mail: faviles@cicy.mx [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburna de Hidalgo, C.P. 97200 Mérida, Yucatán (Mexico); Gonzalez-Chi, P.I; Canché-Escamilla, G.; Duarte-Aranda, S. [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburna de Hidalgo, C.P. 97200 Mérida, Yucatán (Mexico); Yazdani-Pedram, M. [Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, S. Livingstone 1007, Independencia, Santiago (Chile); Toro, P. [Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Beauchef 850, Santiago (Chile); Gamboa, F. [Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Mérida, Depto. de Física Aplicada, Km. 6 Antigua Carretera a Progreso, 97310 Mérida, Yucatán (Mexico); Mazo, M.A.; Nistal, A.; Rubio, J. [Instituto de Cerámica y Vidrio (ICV-CSIC), Kelsen 5, 28049 Madrid (Spain)

    2016-11-01

    Highlights: • The surface of aramid fibers was functionalized by two acid treatments. • The treatment based on HNO{sub 3}/H{sub 2}SO{sub 4} reduced the mechanical properties of the fibers. • CNTs were deposited on the aramid fibers, reaching electrical conductivity. • Homogeneous CNT distribution was achieved by using pristine fibers or chlorosulfonic acid. - Abstract: Multiwall carbon nanotubes (MWCNTs) oxidized by an acid treatment were deposited on the surface of as-received commercial aramid fibers containing a surface coating (“sizing”), and fibers modified by either a chlorosulfonic treatment or a mixture of nitric and sulfuric acids. The surface of the aramid fiber activated by the chemical treatments presents increasing density of CO, COOH and OH functional groups. However, these chemical treatments reduced the tensile mechanical properties of the fibers, especially when the nitric and sulfuric acid mixture was used. Characterization of the MWCNTs deposited on the fiber surface was conducted by scanning electron microscopy, Raman spectroscopy mapping and X-ray photoelectron spectroscopy. These characterizations showed higher areal concentration and more homogeneous distribution of MWCNTs over the aramid fibers for as-received fibers and for those modified with chlorosulfonic acid, suggesting the existence of interaction between the oxidized MWCNTs and the fiber coating. The electrical resistance of the MWCNT-modified aramid yarns comprising ∼1000 individual fibers was in the order of MΩ/cm, which renders multifunctional properties.

  18. Characterization of palm fibers modified with alkaline solution

    International Nuclear Information System (INIS)

    Sipiao, Bryan L.S.; Goulart, Shane A.G.; Mulinari, Daniella R.; Souza Junior, Fernando G. de

    2011-01-01

    This work had the objective of to study one inexpensive and effective technique that enables the application of natural fibers from the Australian Royal Palm as reinforcement in polymer composites. The fibers treated with alkaline solution were characterized by infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) and had their data compared with the fiber in nature. Data showed that the treatment made on fibers surface was effective. (author)

  19. Towards automated visual flexible endoscope navigation.

    Science.gov (United States)

    van der Stap, Nanda; van der Heijden, Ferdinand; Broeders, Ivo A M J

    2013-10-01

    The design of flexible endoscopes has not changed significantly in the past 50 years. A trend is observed towards a wider application of flexible endoscopes with an increasing role in complex intraluminal therapeutic procedures. The nonintuitive and nonergonomical steering mechanism now forms a barrier in the extension of flexible endoscope applications. Automating the navigation of endoscopes could be a solution for this problem. This paper summarizes the current state of the art in image-based navigation algorithms. The objectives are to find the most promising navigation system(s) to date and to indicate fields for further research. A systematic literature search was performed using three general search terms in two medical-technological literature databases. Papers were included according to the inclusion criteria. A total of 135 papers were analyzed. Ultimately, 26 were included. Navigation often is based on visual information, which means steering the endoscope using the images that the endoscope produces. Two main techniques are described: lumen centralization and visual odometry. Although the research results are promising, no successful, commercially available automated flexible endoscopy system exists to date. Automated systems that employ conventional flexible endoscopes show the most promising prospects in terms of cost and applicability. To produce such a system, the research focus should lie on finding low-cost mechatronics and technologically robust steering algorithms. Additional functionality and increased efficiency can be obtained through software development. The first priority is to find real-time, robust steering algorithms. These algorithms need to handle bubbles, motion blur, and other image artifacts without disrupting the steering process.

  20. Training in Endoscopy: Endoscopic Ultrasound

    Directory of Open Access Journals (Sweden)

    Chang Min Cho

    2017-07-01

    Full Text Available Endoscopic ultrasound (EUS has been recently established as an indispensable modality for the diagnosis and management of pancreatobiliary and gastrointestinal (GI disorders. EUS proficiency requires both cognitive and technical abilities, including an understanding of the appropriate indications, the performance of appropriate evaluations before and after the procedure, and the management of procedure-related complications. An increasing demand for skills to handle a growing range of interventional EUS procedures and a continual shortage of EUS training programs are two major obstacles for EUS training. Acquiring the skills necessary to comprehend and conduct EUS often requires training beyond the scope of a standard GI fellowship program. In addition to traditional formal EUS training and preceptorships, regular short-term intensive EUS training programs that provide training at various levels may help EUS practitioners improve and maintain EUS-related knowledges and skills. Theoretical knowledge can be acquired from lectures, textbooks, atlases, slides, videotapes, digital video discs, interactive compact discs, and websites. Informal EUS training is generally based on 1- or 2-day intensive seminars, including didactic lectures, skills demonstrated by expert practitioners through live video-streaming of procedures, and hands-on learning using animal or phantom models.

  1. Endoscopic treatment of prepatellar bursitis.

    Science.gov (United States)

    Huang, Yu-Chih; Yeh, Wen-Lin

    2011-03-01

    Operative treatment of prepatellar bursitis is indicated in intractable bursitis. The most common complication of surgical treatment for prepatellar bursitis is skin problems. For traumatic prepatellar bursitis, we propose a protocol of outpatient endoscopic surgery under local anaesthesia. From September 1996 to February 2001, 60 cases of failed nonoperative treatment for prepatellar bursitis were included. The average age was 33.5 ± 11.1 years (range 21-55). The average operation duration was 18 minutes. Two to three mini-arthroscopic portals were used in our series. No sutures or a simple suture was needed for the portals after operation. After follow-up for an average of 36.3 months, all patients are were symptom-free and had regained knee function. None of the population had local tenderness or hypo-aesthesia around their wound. Their radiographic and sonographic examinations showed no recurrence of bursitis. Outpatient arthroscopic bursectomy under local anaesthesia is an effective procedure for the treatment of post-traumatic prepatellar bursitis after failed conservative treatments. Both the cosmetic results and functional results were satisfactory.

  2. Endoscopic surgery of nasopharyngeal angiofibroma

    Directory of Open Access Journals (Sweden)

    Machado, Silvio

    2010-06-01

    Full Text Available Introduction: Juvenile nasopharyngeal angiofibroma (NAJ is a tumor with vascular component, slow growing, benign but very aggressive because of its local invasiveness. The NAJ is rare, accounting for 0.05% of all head and neck cancers. The classic triad of epistaxis, unilateral nasal obstruction and a mass in the nasopharynx suggests the diagnosis of NAJ and is then supplemented by imaging. Over the past 10 years the treatment of this disease has been discussed with the aim of designing a management protocol. Currently, surgery appears to be the best treatment of the NAJ. Other methods such as hormone therapy, radiotherapy and chemotherapy treatment modalities are now used occasionally as complementary treatments. Objective: To present the cases of this disease in the Hospital Infantil between October 2007 and August 2008. Methods: A retrospective case study of five cases of NAJ underwent surgery solely with endoscopic technique of two surgeons. Classifieds between IIA and IIIA. All patients underwent angiography with embolization of the tumor 3-4 days before surgery. Follow-up after surgery to detect recurrence. Results: There were two relapses in the following two years after surgery. Conclusion: Given the short period of patient follow-up, there were only two relapses in one year. So there is need for further action to claim that this technique has a low recurrence rate, since the recurrence is probably related to incomplete resection the initial tumor.

  3. Modification of endoscopic medial maxillectomy: a novel approach for inverted papilloma of the maxillary sinus.

    Science.gov (United States)

    Ghosh, A; Pal, S; Srivastava, A; Saha, S

    2015-02-01

    To describe modification to endoscopic medial maxillectomy for treating extensive Krouse stage II or III inverted papilloma of the nasal and maxillary sinus. Ten patients with inverted papilloma arising from the nasoantral area underwent diagnostic nasal endoscopy, contrast-enhanced computed tomography scanning of the paranasal sinus and pre-operative biopsy of the nasal mass. They were all managed using endoscopic medial maxillectomy and followed up for seven months to three years without recurrence. Most patients were aged 41-60 years at presentation, and most were male. Presenting symptoms were nasal obstruction, mass in the nasal cavity and epistaxis. In each case, computed tomography imaging showed a mass involving the nasal cavity and maxillary sinus, with bony remodelling. The endoscopic medial maxillectomy approach was modified by making an incision in the pyriform aperture and removing part of the anterolateral wall of the maxilla bone en bloc. Modified endoscopic medial maxillectomy providing full access to the maxillary and ethmoid sinuses is described in detail. This effective, reproducible technique is associated with reduced operative time and morbidity.

  4. Meckel's cave access: anatomic study comparing the endoscopic transantral and endonasal approaches.

    Science.gov (United States)

    Van Rompaey, Jason; Suruliraj, Anand; Carrau, Ricardo; Panizza, Benedict; Solares, C Arturo

    2014-04-01

    Recent advances in endonasal endoscopy have facilitated the surgical access to the lateral skull base including areas such as Meckel's cave. This approach has been well documented, however, few studies have outlined transantral specific access to Meckel's. A transantral approach provides a direct pathway to this region obviating the need for extensive endonasal and transsphenoidal resection. Our aim in this study is to compare the anatomical perspectives obtained in endonasal and transantral approaches. We prepared 14 cadaveric specimens with intravascular injections of colored latex. Eight cadavers underwent endoscopic endonasal transpterygoid approaches to Meckel's cave. Six additional specimens underwent an endoscopic transantral approach to the same region. Photographic evidence was obtained for review. 30 CT scans were analyzed to measure comparative distances to Meckel's cave for both approaches. The endoscopic approaches provided a direct access to the anterior and inferior portions of Meckel's cave. However, the transantral approach required shorter instrumentation, and did not require clearing of the endonasal corridor. This approach gave an anterior view of Meckel's cave making posterior dissection more difficult. A transantral approach to Meckel's cave provides access similar to the endonasal approach with minimal invasiveness. Some of the morbidity associated with extensive endonasal resection could possibly be avoided. Better understanding of the complex skull base anatomy, from different perspectives, helps to improve current endoscopic skull base surgery and to develop new alternatives, consequently, leading to improvements in safety and efficacy.

  5. Multiport Combined Endoscopic Approach to Nonembolized Juvenile Nasopharyngeal Angiofibroma with Parapharyngeal Extension: An Emerging Concept

    Directory of Open Access Journals (Sweden)

    Tiruchy Narayanan Janakiram

    2016-01-01

    Full Text Available Background. Surgical approaches to the parapharyngeal space (PPS are challenging by virtue of deep location and neurovascular content. Juvenile Nasopharyngeal Angiofibroma (JNA is a formidable hypervascular tumor that involves multiple compartments with increase in size. In tumors with extension to parapharyngeal space, the endonasal approach was observed to be inadequate. Combined Endoscopic Endonasal Approaches and Endoscopic Transoral Surgery (EEA-ETOS approach has provided a customized alternative of multicorridor approach to access JNA for its safe and efficient resection. Methods. The study demonstrates a case series of patients of JNA with prestyloid parapharyngeal space extension operated by endoscopic endonasal and endoscopic transoral approach for tumor excision. Results. The multiport EEA-ETOS approach was used to provide wide exposure to access JNA in parapharyngeal space. No major complications were observed. No conversion to external approach was required. Postoperative morbidity was low and postoperative scans showed no residual tumor. A one-year follow-up was maintained and there was no evidence of disease recurrence. Conclusion. Although preliminary, our experience demonstrates safety and efficacy of multiport approach in providing access to multiple compartments, facilitating total excision of JNA in selected cases.

  6. Retrograde gastroesophageal intussusception after peroral endoscopic myotomy in a patient with achalasia cardia: A case report.

    Science.gov (United States)

    Khan, Samiullah; Su, Shuai; Jiang, Kui; Wang, Bang-Mao

    2018-01-01

    Retrograde gastroesophageal intussusception (RGEI) is a relatively rare gastrointestinal (GI) disorder in which a portion of the stomach wall invaginates into the esophagus. More recently, peroral endoscopic myotomy (POEM) has emerged as an endoscopic alternative to surgical myotomy for achalasia, and, to the best of our knowledge, our case is the first RGEI after POEM to be reported. A 22-year-old male was presented with a history of vomiting, intractable retching and hematemesis for 3 days. He had a history of achalasia and underwent POEM 3 years ago caused by symptoms of severe dysphagia to solid and liquid. Initially, the patient was diagnosed with a blood-filled esophagus, and the mid esophagus was occluded with a ball-like mass, however, the final diagnosis of RGEI was made by thoracotomy. A therapeutic strategy of conservative treatment and left transthoracic surgery were applied. The surgery and post operative course were uneventful, and he remained asymptomatic 1 year after operation. POEM is a reliable and minimally invasive endoscopic method for esophageal achalasia. Early recognition and severity of RGEI are essential to decrease the unwanted complications. Upper GI series, esophagogastroduodenoscopy and computed tomography scan are helpful for diagnostic purposes of RGEI. Conservative treatment, endoscopic intervention, and surgery are the mainstay of treatments for RGEI. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  7. Interfacial Studies of Sized Carbon Fiber

    International Nuclear Information System (INIS)

    Shahrul, S. N.; Hartini, M. N.; Hilmi, E. A.; Nizam, A.

    2010-01-01

    This study was performed to investigate the influence of sizing treatment on carbon fiber in respect of interfacial adhesion in composite materials, Epolam registered 2025. Fortafil unsized carbon fiber was used to performed the experiment. The fiber was commercially surface treated and it was a polyacrylonitrile based carbon fiber with 3000 filament per strand. Epicure registered 3370 was used as basic sizing chemical and dissolved in two types of solvent, ethanol and acetone for the comparison purpose. The single pull out test has been used to determine the influence of sizing on carbon fiber. The morphology of carbon fiber was observed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The apparent interfacial strength IFSS values determined by pull out test for the Epicure registered 3370/ethanol sized carbon fiber pointed to a good interfacial behaviour compared to the Epicure registered 3370/acetone sized carbon fiber. The Epicure registered 3370/ethanol sizing agent was found to be effective in promoting adhesion because of the chemical reactions between the sizing and Epolam registered 2025 during the curing process. From this work, it showed that sized carbon fiber using Epicure registered 3370 with addition of ethanol give higher mechanical properties of carbon fiber in terms of shear strength and also provided a good adhesion between fiber and matrix compared to the sizing chemical that contain acetone as a solvent.

  8. Nasal encephalocele: endoscopic excision with anesthetic consideration.

    Science.gov (United States)

    Abdel-Aziz, Mosaad; El-Bosraty, Hussam; Qotb, Mohamed; El-Hamamsy, Mostafa; El-Sonbaty, Mohamed; Abdel-Badie, Hazem; Zynabdeen, Mustapha

    2010-08-01

    Nasal encephalocele may presents as a nasal mass, its treatment is surgical and it should be done early in life. When removal is indicated, there are multiple surgical approaches; including lateral rhinotomy, a transnasal approach and a coronal flap approach. However, the treatment of a basal intranasal encephalocele using transnasal endoscopic approach could obviates the possible morbidity associated with other approaches. The aim of this study was to evaluate the efficacy of endoscopic removal of intranasal encephalocele, also to document the role of anesthetist in the operative and postoperative periods. Nine cases with nasal encephalocele were included in this study; CT and/or MRI were used in their examination. The lesions were removed via transnasal endoscopic approach. Preoperative evaluation, intervention and postoperative follow-up were presented with discussion of anesthesia used for those children. The lesions of all patients were removed successfully with no recurrence through the follow-up period of at least 21 months. No cases showed morbidity or mortality intra- or post-operatively. Endoscopic excision of intranasal encephalocele is an effective method with high success rate. Anesthetist plays an important role in the operative and postoperative period, even during the endoscopic follow up; sedation of the children is usually needed. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  9. Endoscopic and laparoscopic treatment of gastroesophageal reflux.

    Science.gov (United States)

    Watson, David I; Immanuel, Arul

    2010-04-01

    Gastroesophageal reflux is extremely common in Western countries. For selected patients, there is an established role for the surgical treatment of reflux, and possibly an emerging role for endoscopic antireflux procedures. Randomized trials have compared medical versus surgical management, laparoscopic versus open surgery and partial versus total fundoplications. However, the evidence base for endoscopic procedures is limited to some small sham-controlled studies, and cohort studies with short-term follow-up. Laparoscopic fundoplication has been shown to be an effective antireflux operation. It facilitates quicker convalescence and is associated with fewer complications, but has a similar longer term outcome compared with open antireflux surgery. In most randomized trials, antireflux surgery achieves at least as good control of reflux as medical therapy, and these studies support a wider application of surgery for the treatment of moderate-to-severe reflux. Laparoscopic partial fundoplication is an effective surgical procedure with fewer side effects, and it may achieve high rates of patient satisfaction at late follow-up. Many of the early endoscopic antireflux procedures have failed to achieve effective reflux control, and they have been withdrawn from the market. Newer procedures have the potential to fashion a surgical fundoplication. However, at present there is insufficient evidence to establish the safety and efficacy of endoscopic procedures for the treatment of gastroesophageal reflux, and no endoscopic procedure has achieved equivalent reflux control to that achieved by surgical fundoplication.

  10. [Natural Orifice Transluminal Endoscopic Surgery (NOTES)].

    Science.gov (United States)

    Kim, Yong Sik; Kim, Chul Young; Chun, Hoon Jai

    2008-03-01

    Recently, the field of gastrointestinal endoscopy is developing rapidly. Once limited to the gastroinstestinal lumen, the endoscopic technology is now breaking the barriers and extending its boundary to peritoneal and pleural space. In 2004, Dr. Kalloo, a gastroenterologist, observed intraperitoneal organs of a pig using a conventional endoscope through the stomach wall. Since then, new endoscopic technique of intraperitoneal intervention with transluminal approach named the Natural Orifice Transluminal Endoscopic Surgery or NOTES has been introduced. NOTES reaches the target organ by inserting the endoscope through a natural orifice (e.g. mouth, anus, vagina, urethra) and entering the peritoneal lumen by means of making an incision on the luminal wall. After a series of successful experiences in animal studies, NOTES are now being tried on human subjects. There are still many obstacles to overcome, but bright future for this new technology is expected because of its proposed advantages of less pain, lower complication rate, short recovery time, and scarless access. In this review, we plan to learn about NOTES.

  11. Limits of the endoscopic transnasal transtubercular approach.

    Science.gov (United States)

    Gellner, Verena; Tomazic, Peter V

    2018-06-01

    The endoscopic transnasal trans-sphenoidal transtubercular approach has become a standard alternative approach to neurosurgical transcranial routes for lesions of the anterior skull base in particular pathologies of the anterior tubercle, sphenoid plane, and midline lesions up to the interpeduncular cistern. For both the endoscopic and the transcranial approach indications must strictly be evaluated and tailored to the patients' morphology and condition. The purpose of this review was to evaluate the evidence in literature of the limitations of the endoscopic transtubercular approach. A PubMed/Medline search was conducted in January 2018 entering following keywords. Upon initial screening 7 papers were included in this review. There are several other papers describing the endoscopic transtubercular approach (ETTA). We tried to list the limitation factors according to the actual existing literature as cited. The main limiting factors are laterally extending lesions in relation to the optic canal and vascular encasement and/or unfavorable tumor tissue consistency. The ETTA is considered as a high level transnasal endoscopic extended skull base approach and requires excellent training, skills and experience.

  12. Transanal endoscopic microsurgery: a New Zealand experience.

    Science.gov (United States)

    Bloomfield, Ian; Van Dalen, Roelof; Lolohea, Simione; Wu, Linus

    2017-12-03

    Transanal endoscopic microsurgery (TEMS) is a proven alternative therapy to either radical surgery or endoscopic mucosal resection for rectal neoplasms. It has proven benefits with lower morbidity and mortality compared with total mesorectal excision, and a lower local recurrence rate when compared to endoscopic mucosal techniques. A retrospective data collection of TEMS procedures performed through Waikato District Health Board, New Zealand, from 2010 to 2015 was conducted. Supportive follow-up data were sourced from patient records and from local centres around New Zealand. A total of 137 procedures were performed over the study period, with five being repeat procedures. Procedures were mostly performed for benign lesions (66.4%) with an overall complication rate of 15.3%, only five of which were Clavien-Dindo grade III (3.6%). Our local recurrence rate after resection of benign lesions was 5.1%. Our data set demonstrates the TEMS procedure to be safe compared to radical resection (total mesorectal excision) for sessile rectal lesions. Close endoscopic follow-up is recommended, especially for close or incomplete margins. Good therapeutic results can be obtained for appropriately selected early malignant lesions. TEMS provides better oncological results than endoscopic mucosal resection or transanal excision. © 2017 Royal Australasian College of Surgeons.

  13. 21 CFR 876.4300 - Endoscopic electrosurgical unit and accessories.

    Science.gov (United States)

    2010-04-01

    ... Endoscopic electrosurgical unit and accessories. (a) Identification. An endoscopic electrosurgical unit and... device includes the electrosurgical generator, patient plate, electric biopsy forceps, electrode, flexible snare, electrosurgical alarm system, electrosurgical power supply unit, electrical clamp, self...

  14. Endoscopic Radial Artery Harvest for Coronary Artery Bypass Surgery

    Directory of Open Access Journals (Sweden)

    Kuan-Ming Chiu

    2006-01-01

    Conclusion: Endoscopic harvest of the radial artery is technically demanding, but excellent results can be achieved. The endoscopic approach can provide suitable conduits in a less invasive way than the open harvest technique.

  15. Sequelae of Endoscopic Inguinal Hernia Repair : Incidence, evaluation and management

    NARCIS (Netherlands)

    Burgmans, J.P.J.

    2015-01-01

    The endoscopic preperitoneal technique (TEP) is an appealing inguinal hernia repair technique, theoretically superior to other approaches. In practice some problems remain unsolved. Real incidences of chronic postoperative inguinal pain (CPIP) and other important sequelae of endoscopic hernia repair

  16. Training course on optical telecommunication and multimedia technologies for specialists in endoscopic video surgery

    Science.gov (United States)

    Agliullin, Arthur F.; Gusev, Valery F.; Morozov, Oleg G.; Samigullin, Rustem R.; Akul'shin, Alexander, Iv.; Bagapov, Nail N.

    2011-04-01

    The program of courses is recommended for the experts working in endoscopy area, surgery, diagnostics, to developers of optical, optoelectronic and electronic equipment, and also for students and the post-graduate students of telecommunication high schools in addition trained on specializations of biomedical engineering. It urged to help the future researcher, engineer and doctor to understand mechanisms of images formation and display, to understand more deeply procedures of their processing and transfer on telecommunication channels of the various natures, to master modern reports of record and video and audio information reproduction. The separate section is devoted to questions of designing of surgical toolkit compatible with fiber-optical endoscopes.

  17. Percutaneous endoscopic gastrostomy in children

    Directory of Open Access Journals (Sweden)

    Jye Hae Park

    2011-01-01

    Full Text Available Purpose: Percutaneous endoscopic gastrostomy (PEG can improve nutritional status and reduce the amount of time needed to feed neurologically impaired children. We evaluated the characteristics, complications, and outcomes of neurologically impaired children treated with PEG. Methods: We retrospectively reviewed the records of 32 neurologically impaired children who underwent PEG between March 2002 and August 2008 at our medical center. Forty-two PEG procedures comprising 32 PEG insertions and 10 PEG exchanges, were performed. The mean follow-up time was 12.2 (6.6 months. Results: Mean patient age was 9.4 (4.5 years. The main indications for PEG insertion were swallowing difficulty with GI bleeding due to nasogastric tube placement and/or the presence of gastroesophageal reflux disease (GERD. The overall rate of complications was 47%, with early complications evident in 25% of patients and late complications in 22%. The late complications included one gastro-colic fistula, two cases of aggravated GERD, and four instances of wound infection. Among the 15 patients with histological evidence of GERD before PEG, 13 (87% had less severe GERD, experienced no new aspiration events, and showed increased body weight after PEG treatment. Conclusion: PEG is a safe, effective, and relatively simple technique affording long-term enteral nutritional support in neurologically impaired children. Following PEG treatment, the body weight of most patients increased and the levels of vomiting, GI bleeding, and aspiration fell. We suggest that PEG with post-procedural observation be considered for enteral nutritional support of neurologically impaired children.

  18. Cost-effectiveness of endoscopic ultrasonography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography in patients suspected of pancreaticobiliary disease

    DEFF Research Database (Denmark)

    Ainsworth, A P; Rafaelsen, S R; Wamberg, P A

    2004-01-01

    BACKGROUND: It is not known whether initial endoscopic ultrasonography (EUS) or magnetic resonance cholangiopancreatography (MRCP) is more cost effective than endoscopic retrograde cholangiopancreatography (ERCP). METHODS: A cost-effectiveness analysis of EUS, MRCP and ERCP was performed on 163...

  19. Endoscopic management of peripancreatic fluid collections.

    Science.gov (United States)

    Goyal, Jatinder; Ramesh, Jayapal

    2015-07-01

    Peripancreatic fluid collections are a well-known complication of pancreatitis and can vary from fluid-filled collections to entirely necrotic collections. Although most of the fluid-filled pseudocysts tend to resolve spontaneously with conservative management, intervention is necessary in symptomatic patients. Open surgery has been the traditional treatment modality of choice though endoscopic, laparoscopic and transcutaneous techniques offer alternative drainage approaches. During the last decade, improvement in endoscopic ultrasound technology has enabled real-time access and drainage of fluid collections that were previously not amenable to blind transmural drainage. This has initiated a trend towards use of this modality for treatment of pseudocysts. In this review, we have summarised the existing evidence for endoscopic drainage of peripancreatic fluid collections from published studies.

  20. Diagnosis and treatment with endoscopic retrograde cholangiopancreatography

    International Nuclear Information System (INIS)

    Soendenaa, K.; Horn, A.; Viste, A.

    1994-01-01

    Endoscopic retrograde cholangiopancreatography (ERCP) was carried out for the first time in 1968. Five years later endoscopic sphincterotomy was performed. Since then both modalities have become established as necessary adjuncts in the diagnosis and treatment of patients with pathology in the bile duct or pancreas. The main indication is common bile duct stone, and as a consequence of this treatment fewer patients are now treated surgically. Patients with malignant bile duct obstruction can be given reasonable palliation of both jaundice and pruritus and therefore improved quality of life. Some reports indicate that endoscopic drainage may be useful for pancreatic stenosis. Complications are few, but vigilance and prompt treatment is necessary to keep morbidity at a minimum. Follow-up after several years shows that sphincterotomy is successful also in the long term. The authors discuss the present diagnostic and therapeutic situation. 31 refs., 2 tabs

  1. Endoscopic facial skeletal surgery using a neuronavigator.

    Science.gov (United States)

    Sakai, Y; Kobayashi, S; Watanabe, E; Sekiya, S; Ohmori, K

    1996-09-01

    In the reconstruction of asymmetrical deformities of the facial skeleton, both an endoscope and a neuronavigator have been used. The endoscope allows the surgeon a wide view of the object on a television monitor, reduces the scarring, minimizes the undermined field, and reduces the need to work blind. The neuronavigator is a frameless computed tomographic stereotactic device that has been mainly used in neurosurgery. The device is easy to use and can offer the surgeon three-dimensional coordinates of the status during the operation. We have used this new technique in three clinical cases, two involving augmentation of the zygomatic bone on one side and one involving reduction of the frontal bone on one side. The surgical techniques we used and the versatility of both the endoscope and the neuronavigator are discussed herein based on our own experience.

  2. Endoscopic and Photodynamic Therapy of Cholangiocarcinoma.

    Science.gov (United States)

    Meier, Benjamin; Caca, Karel

    2016-12-01

    Most patients with cholangiocarcinoma (CCA) have unresectable disease. Endoscopic bile duct drainage is one of the major objectives of palliation of obstructive jaundice. Stent implantation using endoscopic retrograde cholangiography is considered to be the standard technique. Unilateral versus bilateral stenting is associated with different advantages and disadvantages; however, a standard approach is still not defined. As there are various kinds of stents, there is an ongoing discussion on which stent to use in which situation. Palliation of obstructive jaundice can be augmented through the use of photodynamic therapy (PDT). Studies have shown a prolonged survival for the combinations of PDT and different stent applications as well as combinations of PDT and additional systemic chemotherapy. More well-designed studies are needed to better evaluate and standardize endoscopic treatment of unresectable CCA.

  3. Post-endoscopic biliary sphincterotomy bleeding: an interventional radiology approach.

    LENUS (Irish Health Repository)

    Dunne, Ruth

    2013-12-01

    Endoscopic sphincterotomy is an integral component of endoscopic retrograde cholangiopancreatography. Post-sphincterotomy hemorrhage is a recognized complication. First line treatment involves a variety of endoscopic techniques performed at the time of sphincterotomy. If these are not successful, transcatheter arterial embolization or open surgical vessel ligation are therapeutic considerations.

  4. Brain PET scan

    Science.gov (United States)

    ... results on a PET scan. Blood sugar or insulin levels may affect the test results in people with diabetes . PET scans may be done along with a CT scan. This combination scan is called a PET/CT. Alternative Names Brain positron emission tomography; PET scan - brain References Chernecky ...

  5. Design of signal reception and processing system of embedded ultrasonic endoscope

    Science.gov (United States)

    Li, Ming; Yu, Feng; Zhang, Ruiqiang; Li, Yan; Chen, Xiaodong; Yu, Daoyin

    2009-11-01

    Embedded Ultrasonic Endoscope, based on embedded microprocessor and embedded real-time operating system, sends a micro ultrasonic probe into coelom through the biopsy channel of the Electronic Endoscope to get the fault histology features of digestive organs by rotary scanning, and acquires the pictures of the alimentary canal mucosal surface. At the same time, ultrasonic signals are processed by signal reception and processing system, forming images of the full histology of the digestive organs. Signal Reception and Processing System is an important component of Embedded Ultrasonic Endoscope. However, the traditional design, using multi-level amplifiers and special digital processing circuits to implement signal reception and processing, is no longer satisfying the standards of high-performance, miniaturization and low power requirements that embedded system requires, and as a result of the high noise that multi-level amplifier brought, the extraction of small signal becomes hard. Therefore, this paper presents a method of signal reception and processing based on double variable gain amplifier and FPGA, increasing the flexibility and dynamic range of the Signal Reception and Processing System, improving system noise level, and reducing power consumption. Finally, we set up the embedded experiment system, using a transducer with the center frequency of 8MHz to scan membrane samples, and display the image of ultrasonic echo reflected by each layer of membrane, with a frame rate of 5Hz, verifying the correctness of the system.

  6. ENDOSCOPIC TECHNOLOGIES IN EARLY RECTAL CANCER TREATMENT

    Directory of Open Access Journals (Sweden)

    D. V. Samsonov

    2015-01-01

    Full Text Available Total mesorectal excision is the “golden standard” of surgical treatment for rectal cancer. Development of endoscopic technologies allowed to implement the benefits of minimally invasive surgery in early rectal cancer treatment, decrease morbidity and mortality, improve functional outcome and quality of life. Oncological safety of this method is still a subject for discussion due to lack of lymph node harvest. Endoscopic operations for early rectal cancer are being actively implemented in daily practice, but lack of experience does not allow to include this method in national clinical prac-tice guidelines.

  7. Endoscopic management of acute peptic ulcer bleeding.

    Science.gov (United States)

    Lu, Yidan; Chen, Yen-I; Barkun, Alan

    2014-12-01

    This review discusses the indications, technical aspects, and comparative effectiveness of the endoscopic treatment of upper gastrointestinal bleeding caused by peptic ulcer. Pre-endoscopic considerations, such as the use of prokinetics and timing of endoscopy, are reviewed. In addition, this article examines aspects of postendoscopic care such as the effectiveness, dosing, and duration of postendoscopic proton-pump inhibitors, Helicobacter pylori testing, and benefits of treatment in terms of preventing rebleeding; and the use of nonsteroidal anti-inflammatory drugs, antiplatelet agents, and oral anticoagulants, including direct thrombin and Xa inhibitors, following acute peptic ulcer bleeding. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Low-fiber diet

    Science.gov (United States)

    ... residue; Low-fiber diet; Fiber restricted diet; Crohn disease - low fiber diet; Ulcerative colitis - low fiber diet; ... them if they do not contain seeds or pulp: Yellow squash (without seeds) Spinach Pumpkin Eggplant Potatoes, ...

  9. Photovoltaic fibers

    Science.gov (United States)

    Gaudiana, Russell; Eckert, Robert; Cardone, John; Ryan, James; Montello, Alan

    2006-08-01

    It was realized early in the history of Konarka that the ability to produce fibers that generate power from solar energy could be applied to a wide variety of applications where fabrics are utilized currently. These applications include personal items such as jackets, shirts and hats, to architectural uses such as awnings, tents, large covers for cars, trucks and even doomed stadiums, to indoor furnishings such as window blinds, shades and drapes. They may also be used as small fabric patches or fiber bundles for powering or recharging batteries in small sensors. Power generating fabrics for clothing is of particular interest to the military where they would be used in uniforms and body armor where portable power is vital to field operations. In strong sunlight these power generating fabrics could be used as a primary source of energy, or they can be used in either direct sunlight or low light conditions to recharge batteries. Early in 2002, Konarka performed a series of proof-of-concept experiments to demonstrate the feasibility of building a photovoltaic cell using dye-sensitized titania and electrolyte on a metal wire core. The approach taken was based on the sequential coating processes used in making fiber optics, namely, a fiber core, e.g., a metal wire serving as the primary electrode, is passed through a series of vertically aligned coating cups. Each of the cups contains a coating fluid that has a specific function in the photocell. A second wire, used as the counter electrode, is brought into the process prior to entering the final coating cup. The latter contains a photopolymerizable, transparent cladding which hardens when passed through a UV chamber. Upon exiting the UV chamber, the finished PV fiber is spooled. Two hundred of foot lengths of PV fiber have been made using this process. When the fiber is exposed to visible radiation, it generates electrical power. The best efficiency exhibited by these fibers is 6% with an average value in the 4

  10. Endoscopic monitoring the estrous phase of Arabian mares with assaying its biopsy

    Directory of Open Access Journals (Sweden)

    Mohamed Fathi

    2017-01-01

    Full Text Available Objective: To evaluate the changes occur in the vagina, cervix and endometrium during the pre- ovulatory period in Arabian mares by using endoscope as a diagnostic tool as well as the availability of taking an endoscopic biopsy during this stage.Methods: Ten cyclic and healthy arabian mares were subjected to ultrasound scanning of their ovaries to estimate the diameter of the preovulatory follicles, collection of blood samples for estimating the hormonal levels (Estradiol-17 β and progestrone for confirming the estrous phase, endoscopic monitoring their vagina, cervix and endometrium, the availability of taking biopsical samples and histological examination of the obtained samples.Results: The obtained data revealed that, the mean diameter of the preovulatory follicles was (3.95±0.34 cm, the plasma estradiol and progestrone levels were (85.98±5.26 pg/mL and (0.73±0.23 ng/mL, respectively, endoscopic monitoring the vagina, cervix and endometrium revealed hyperemic vaginal mucous membrane, soft and opened cervical ostium with abundant estrous mucous and folding, hyperemic and edematous appearance of the endometrium, respectively and the histological features of the biopsical endometrial samples revealed that, The lamina propria-sub mucosa was packed with simple or branched tubular glands lined with simple columnar epithelium showing oval or rounded dark nuclei with different degrees of secretory activities of the glands.Conclusions: The endoscope proved to be a reliable tool for confirming the estrous phase in mares and monitoring the gross features of the vagina, the cervix and the endometrium, in addition to the availability of taking biopsical smears.

  11. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  12. All-plastic fiber-based pressure sensor

    DEFF Research Database (Denmark)

    Bundalo, Ivan-Lazar; Lwin, Richard; Leon-Saval, Sergio

    2016-01-01

    We present a feasibility study and a prototype of an all-plastic fiber-based pressure sensor. The sensor is based on long period gratings inscribed for the first time to the best of our knowledge by a CO2 laser in polymethyl methacrylate (PMMA) microstructured fibers and coupled to a pod......-like transducer that converts pressure to strain. The sensor prototype was characterized for pressures up to 150 mbars, and various parameters related to its construction were also characterized in order to enhance sensitivity. We consider this sensor in the context of future applications in endoscopic pressure...... sensors....

  13. Per-oral endoscopic myotomy: Major advance in achalasia treatment and in endoscopic surgery

    Science.gov (United States)

    Friedel, David; Modayil, Rani; Stavropoulos, Stavros N

    2014-01-01

    Per-oral endoscopic myotomy (POEM) represents a natural orifice endoscopic surgery (NOTES) approach to laparoscopy Heller myotomy (LHM). POEM is arguably the most successful clinical application of NOTES. The growth of POEM from a single center in 2008 to approximately 60 centers worldwide in 2014 with several thousand procedures having been performed attests to the success of POEM. Initial efficacy, safety and acid reflux data suggest at least equivalence of POEM to LHM, the previous gold standard for achalasia therapy. Adjunctive techniques used in the West include impedance planimetry for real-time intraprocedural luminal assessment and endoscopic suturing for challenging mucosal defect closures during POEM. The impact of POEM extends beyond the realm of esophageal motility disorders as it is rapidly popularizing endoscopic submucosal dissection in the West and spawning offshoots that use the submucosal tunnel technique for a host of new indications ranging from resection of tumors to pyloromyotomy for gastroparesis. PMID:25548473

  14. Endoscope-Assisted Transoral Fixation of Mandibular Condyle Fractures: Submandibular Versus Transoral Endoscopic Approach.

    Science.gov (United States)

    Hwang, Na-Hyun; Lee, Yoon-Hwan; You, Hi-Jin; Yoon, Eul-Sik; Kim, Deok-Woo

    2016-07-01

    In recent years, endoscope-assisted transoral approach for condylar fracture treatment has attracted much attention. However, the surgical approach is technically challenging: the procedure requires specialized instruments and the surgeons experience a steep learning curve. During the transoral endoscopic (TE) approach several instruments are positioned through a narrow oral incision making endoscope maneuvering very difficult. For this reason, the authors changed the entry port of the endoscope from transoral to submandibular area through a small stab incision. The aim of this study is to assess the advantage of using the submandibular endoscopic intraoral approach (SEI).The SEI approach requires intraoral incision for fracture reduction and fixation, and 4 mm size submandibular stab incision for endoscope and traction wires. Fifteen patients with condyle neck and subcondyle fractures were operated under the submandibular approach and 15 patients with the same diagnosis were operated under the standard TE approach.The SEI approach allowed clear visualization of the posterior margin of the ramus and condyle, and the visual axis was parallel to the condyle ramus unit. The TE approach clearly shows the anterior margin of the condyle and the sigmoid notch. The surgical time of the SEI group was 128 minutes and the TE group was 120 minutes (P >0.05). All patients in the TE endoscope group were fixated with the trocar system, but only 2 lower neck fracture patients in the SEI group required a trocar. The other 13 subcondyle fractures were fixated with an angulated screw driver (P <0.05). There were no differences in complication and surgical outcomes.The submandibular endoscopic approach has an advantage of having more space with good visualization, and facilitated the use of an angulated screw driver.

  15. Endoscopic submucosal dissection for locally recurrent colorectal lesions after previous endoscopic mucosal resection.

    Science.gov (United States)

    Zhou, Pinghong; Yao, Liqing; Qin, Xinyu; Xu, Meidong; Zhong, Yunshi; Chen, Weifeng

    2009-02-01

    The objective of this study was to determine the efficacy and safety of endoscopic submucosal dissection for locally recurrent colorectal cancer after previous endoscopic mucosal resection. A total of 16 patients with locally recurrent colorectal lesions were enrolled. A needle knife, an insulated-tip knife and a hook knife were used to resect the lesion along the submucosa. The rate of the curative resection, procedure time, and incidence of complications were evaluated. Of 16 lesions, 15 were completely resected with endoscopic submucosal dissection, yielding an en bloc resection rate of 93.8 percent. Histologic examination confirmed that lateral and basal margins were cancer-free in 14 patients (87.5 percent). The average procedure time was 87.2 +/- 60.7 minutes. None of the patients had immediate or delayed bleeding during or after endoscopic submucosal dissection. Perforation in one patient (6.3 percent) was the only complication and was managed conservatively. The mean follow-up period was 15.5 +/- 6.8 months; none of the patients experienced lesion residue or recurrence. Endoscopic submucosal dissection appears to be effective for locally recurrent colorectal cancer after previous endoscopic mucosal resection, making it possible to resect whole lesions and provide precise histologic information.

  16. Endoscopic therapy of neoplasia related to Barrett's esophagus and endoscopic palliation of esophageal cancer.

    Science.gov (United States)

    Vignesh, Shivakumar; Hoffe, Sarah E; Meredith, Kenneth L; Shridhar, Ravi; Almhanna, Khaldoun; Gupta, Akshay K

    2013-04-01

    Barrett's esophagus (BE) is the most important identifiable risk factor for the progression to esophageal adenocarcinoma. This article reviews the current endoscopic therapies for BE with high-grade dysplasia and intramucosal cancer and briefly discusses the endoscopic palliation of advanced esophageal cancer. The diagnosis of low-grade or high-grade dysplasia (HGD) is based on several cytologic criteria that suggest neoplastic transformation of the columnar epithelium. HGD and carcinoma in situ are regarded as equivalent. The presence of dysplasia, particularly HGD, is also a risk factor for synchronous and metachronous adenocarcinoma. Dysplasia is a marker of adenocarcinoma and also has been shown to be the preinvasive lesion. Esophagectomy has been the conventional treatment for T1 esophageal cancer and, although debated, is an appropriate option in some patients with HGD due to the presence of occult cancer in over one-third of patients. Endoscopic ablative modalities (eg, photodynamic therapy and cryoablation) and endoscopic resection techniques (eg, endoscopic mucosal resection) have demonstrated promising results. The significant morbidity and mortality of esophagectomy makes endoscopic treatment an attractive potential option.

  17. Rendezvous endoscopic recanalization for complete esophageal obstruction.

    Science.gov (United States)

    Fusco, Stefano; Kratt, Thomas; Gani, Cihan; Stueker, Dietmar; Zips, Daniel; Malek, Nisar P; Goetz, Martin

    2018-03-30

    Complete esophageal obstruction after (chemo)radiation for head and neck cancers is rare. However, inability to swallow one's own saliva strongly inflicts upon quality of life. Techniques for endoscopic recanalization in complete obstruction are not well established. We assessed the efficacy and safety of rendezvous recanalization. We performed a retrospective review of all patients who underwent endoscopic recanalization of complete proximal esophageal obstruction after radiotherapy between January 2009 and June 2016. Technical success was defined as an ability to pass an endoscope across the recanalized lumen, clinical success by changes in the dysphagia score. Adverse events were recorded prospectively. 19 patients with complete obstruction (dysphagia IV°), all of whom had failed at least one trial of conventional dilatation, underwent recanalization by endoscopic rendezvous, a combined approach through a gastrostomy and perorally under fluoroscopic control. Conscious sedation was used in all patients. In 18/19 patients (94.7%), recanalization was technically successful. In 14/18 patients (77.8%), the post-intervention dysphagia score changed to ≤ II. Three patients had their PEG removed. Factors negatively associated with success were obstruction length of 50 mm; and tumor recurrence for long-term success. No severe complications were recorded. Rendezvous recanalization for complete esophageal obstruction is a reliable and safe method to re-establish luminal patency. Differences between technical and clinical success rates highlight the importance of additional functional factors associated with dysphagia. Given the lack of therapeutic alternatives, rendezvous recanalization is a valid option to improve dysphagia.

  18. Outcome of Endoscopic Transsphenoidal Surgery for Acromegaly.

    Science.gov (United States)

    Kim, Jung Hee; Hur, Kyu Yeon; Lee, Jung Hyun; Lee, Ji Hyun; Se, Young-Bem; Kim, Hey In; Lee, Seung Hoon; Nam, Do-Hyun; Kim, Seong Yeon; Kim, Kwang-Won; Kong, Doo-Sik; Kim, Yong Hwy

    2017-08-01

    Endoscopic transsphenoidal surgery has recently been introduced in pituitary surgery. We investigated outcomes and complications of endoscopic surgery in 2 referral centers in Korea. We enrolled 134 patients with acromegaly (microadenomas, n = 15; macroadenomas, n = 119) who underwent endoscopic transsphenoidal surgery at Seoul National University Hospital (n = 74) and Samsung Medical Center (n = 60) between January 2009 and March 2016. Remission was defined as having a normal insulin-like growth factor-1 and a suppressed growth hormone (GH) surgery, normal pituitary function was maintained in 34 patients (25.4%). Sixty-four patients (47.7%) presented complete (n = 59, 44.0%) or incomplete (n = 5, 3.7%) recovery of pituitary function. Hypopituitarism persisted in 20 patients (14.9%) and worsened in 16 patients (11.9%). Postoperatively, transient diabetes insipidus was reported in 52 patients (38.8%) but only persisted in 2 patients (1.5%). Other postoperative complications were epistaxis (n = 2), cerebral fluid leakage (n = 4), infection (n = 1), and intracerebral hemorrhage (n = 1). Endoscopic transsphenoidal surgery for acromegaly presented high remission rates and a low incidence of endocrine deficits and complications. Regardless of surgical techniques, invasive pituitary tumors were associated with poor outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Upper gastrointestinal endoscopic findings and prevalence of ...

    African Journals Online (AJOL)

    Upper gastrointestinal endoscopic findings and prevalence of Helicobacter pylori infection among adult patients with dyspepsia in northern Tanzania. ... Endoscopy (EGD) for initial work up. Study on antimicrobial susceptibility pattern of H. pylori is recommended to guide choices for evidence based treatment option.

  20. Update on the endoscopic treatments for achalasia

    Science.gov (United States)

    Uppal, Dushant S; Wang, Andrew Y

    2016-01-01

    Achalasia is the most common primary motility disorder of the esophagus and presents as dysphagia to solids and liquids. It is characterized by impaired deglutitive relaxation of the lower esophageal sphincter. High-resolution manometry allows for definitive diagnosis and classification of achalasia, with type II being the most responsive to therapy. Since no cure for achalasia exists, early diagnosis and treatment of the disease is critical to prevent end-stage disease. The central tenant of diagnosis is to first rule out mechanical obstruction due to stricture or malignancy, which is often accomplished by endoscopic and fluoroscopic examination. Therapeutic options include pneumatic dilation (PD), surgical myotomy, and endoscopic injection of botulinum toxin injection. Heller myotomy and PD are more efficacious than pharmacologic therapies and should be considered first-line treatment options. Per oral endoscopic myotomy (POEM) is a minimally-invasive endoscopic therapy that might be as effective as surgical myotomy when performed by a trained and experienced endoscopist, although long-term data are lacking. Overall, therapy should be individualized to each patient’s clinical situation and based upon his or her risk tolerance, operative candidacy, and life expectancy. In instances of therapeutic failure or symptom recurrence re-treatment is possible and can include PD or POEM of the wall opposite the site of prior myotomy. Patients undergoing therapy for achalasia require counseling, as the goal of therapy is to improve swallowing and prevent late manifestations of the disease rather than to restore normal swallowing, which is unfortunately impossible. PMID:27818585

  1. Successful Endoscopic Therapy of Traumatic Bile Leaks

    Directory of Open Access Journals (Sweden)

    Matthew P. Spinn

    2013-02-01

    Full Text Available Traumatic bile leaks often result in high morbidity and prolonged hospital stay that requires multimodality management. Data on endoscopic management of traumatic bile leaks are scarce. Our study objective was to evaluate the efficacy of the endoscopic management of a traumatic bile leak. We performed a retrospective case review of patients who were referred for endoscopic retrograde cholangiopancreatography (ERCP after traumatic bile duct injury secondary to blunt (motor vehicle accident or penetrating (gunshot trauma for management of bile leaks at our tertiary academic referral center. Fourteen patients underwent ERCP for the management of a traumatic bile leak over a 5-year period. The etiology included blunt trauma from motor vehicle accident in 8 patients, motorcycle accident in 3 patients and penetrating injury from a gunshot wound in 3 patients. Liver injuries were grade III in 1 patient, grade IV in 10 patients, and grade V in 3 patients. All patients were treated by biliary stent placement, and the outcome was successful in 14 of 14 cases (100%. The mean duration of follow-up was 85.6 days (range 54-175 days. There were no ERCP-related complications. In our case review, endoscopic management with endobiliary stent placement was found to be successful and resulted in resolution of the bile leak in all 14 patients. Based on our study results, ERCP should be considered as first-line therapy in the management of traumatic bile leaks.

  2. An observational study on oesophageal variceal endoscopic ...

    African Journals Online (AJOL)

    An observational study on oesophageal variceal endoscopic injection sclerotherapy in patients with portal hypertension seen at the Centre for Clinical Research, ... The report concludes that variceal injection sclerotherapy is a useful method of treating oesophageal varices and can be performed on an out patient basis.

  3. ENDOSCOPIC TREATMENT OF THE HYPOPHARYNGEAL (ZENKERS) DIVERTICULUM

    NARCIS (Netherlands)

    WOUTERS, B; VANOVERBEEK, JJM

    Over the years the techniques for endoscopic treatment of Zenker's diverticulum have been improved. Initially, in 1964, we used the electrocoagulation technique as described by Dohlman, but currently we prefer to sever the tissue bridge between the diverticulum and esophagus with the CO2 laser under

  4. Liver parenchumography following endoscopic retrograde cholangiopancreatography (ERCP)

    International Nuclear Information System (INIS)

    Revert, A.; Arana, E.; Pertejo, V.; Berenguer, M.; Masip, M.J.

    1998-01-01

    Focal liver opacification during endoscopic retrograde cholangiography (ERCP) is an uncommon complication caused by excessive pressure during contrast injection. In this situation, ERCP must be interrupted and the position of the cannula checked. We recommend that these images be excluded from the diagnosis of tumor or cystic cavities. 4 refs

  5. Subcutaneous endoscopically assisted ligation using miniport for ...

    African Journals Online (AJOL)

    miniport for the treatment of girls with inguinal hernia. Akinari Hinoki*, Ikeda ... method using subcutaneous endoscopically assisted ligation (SEAL) for the ... the open technique and an additional 2 mm miniport). A ... (unilateral, n = 9) or 42 ± 8 min (bilateral, n = 5). The mean .... Methods of laparoscopic repair have recently ...

  6. Early endoscopic realignment in posterior urethral injuries.

    Science.gov (United States)

    Shrestha, B; Baidya, J L

    2013-01-01

    Posterior urethral injury requires meticulous tertiary care and optimum expertise to manage successfully. The aim of our study is to describe our experiences with pelvic injuries involving posterior urethra and their outcome after early endoscopic realignment. A prospective study was carried out in 20 patients with complete posterior urethral rupture, from November 2007 till October 2010. They presented with blunt traumatic pelvic fracture and underwent primary realignment of posterior urethra in our institute. The definitive diagnosis of urethral rupture was made after retrograde urethrography and antegrade urethrography where applicable. The initial management was suprapubic catheter insertion after primary trauma management in casualty. After a week of conservative management with intravenous antibiotics and pain management, patients were subjected to the endoscopic realignment. The follow up period was at least six months. The results were analyzed with SPSS software. After endoscopic realignment, all patients were advised CISC for the initial 3 months. All patients voided well after three months of CISC. However, 12 patients were lost to follow up by the end of 6 postoperative months. Out of eight remaining patients, two had features of restricture and were managed with DVU followed by CISC again. One patient with restricture had some degree of erectile dysfunction who improved significantly after phospodiesterase inhibitors. None of the patients had features of incontinence. Early endoscopic realignment of posterior urethra is a minimally invasive modality in the management of complete posterior urethral injury with low rates of incontinence and impotency.

  7. Endoscopic Third Ventriculostomy: Success and Failure.

    Science.gov (United States)

    Deopujari, Chandrashekhar E; Karmarkar, Vikram S; Shaikh, Salman T

    2017-05-01

    Endoscopic third ventriculostomy (ETV) has now become an accepted mode of hydrocephalus treatment in children. Varying degrees of success for the procedure have been reported depending on the type and etiology of hydrocephalus, age of the patient and certain technical parameters. Review of these factors for predictability of success, complications and validation of success score is presented.

  8. Anaesthetic management of endoscopic resection of juvenile ...

    African Journals Online (AJOL)

    P Khanna, BR Ray, R Sinha, R Kumar, K Sikka, AC Singh ... We present the anaesthetic management of endoscopic resection of 14 JNAs, together with a review. ... Mean duration of surgery was 197.14 ± 77 minutes, and median blood loss ...

  9. An illumination system for endoscopic applications

    DEFF Research Database (Denmark)

    2013-01-01

    The present disclosure relates to an illumination system for endoscopic applications comprising at least one substantially monochromatic light source having a predefined central wavelength between 400 and 500 nm or between 500 and 550 nm, an optical transmission path adapted to guide light emanat...... for photodynamic diagnosis and/or therapy of bladder cancer is further disclosed herein....

  10. Subcutaneous endoscopically assisted ligation using miniport for ...

    African Journals Online (AJOL)

    Background This report describes the first miniport method using subcutaneous endoscopically assisted ligation (SEAL) for the treatment of girls with inguinal hernia. To validate its safety and efficacy, the authors evaluated their early experiences. Methods Between April 2014 and December 2014, 19 SEALs using miniport ...

  11. Endoscopic management of bile leaks after laparoscopic ...

    African Journals Online (AJOL)

    2013-11-04

    Nov 4, 2013 ... operative treatment is necessary, repair by a surgeon with expertise in biliary ... vascular injuries or other endoscopic findings requiring surgical or radiological intervention. Of 84 patients ..... necrosis and unrecognised distal CD injury. ... placement of multiple simultaneous stents, an alternative option.

  12. Optimization of portal placement for endoscopic calcaneoplasty

    NARCIS (Netherlands)

    van Sterkenburg, Maayke N.; Groot, Minke; Sierevelt, Inger N.; Spennacchio, Pietro A.; Kerkhoffs, Gino M. M. J.; van Dijk, C. Niek

    2011-01-01

    The purpose of our study was to determine an anatomic landmark to help locate portals in endoscopic calcaneoplasty. The device for optimal portal placement (DOPP) was developed to measure the distance from the distal fibula tip to the calcaneus (DFC) in 28 volunteers to determine the location of the

  13. Influence of cellulose fibers on structure and properties of fiber reinforced foam concrete

    Directory of Open Access Journals (Sweden)

    Fedorov Valeriy

    2018-01-01

    Full Text Available One of the promising means of foamed concrete quality improvement is micro-reinforcement by adding synthetic and mineral fibers to the base mix. This research is the first to investigate peculiarities of using recycled cellulose fiber extracted from waste paper for obtaining fiber reinforced foam concrete. The paper presents results of experimental research on the influence of cellulose fibers on structure and properties of fiber reinforced foam concrete by using methods of chemical analysis and scanning electron microscopy. The research determines peculiarities of new formations appearance and densification of binder hydration products in the contact zone between fiber and cement matrix, which boost mechanical strength of fiber reinforced foam concrete. Physico-mechanical properties of fiber reinforced foam concrete were defined depending on the amount of recycled cellulose fiber added to the base mix. It was found that the use of recycled cellulose fibers allows obtaining structural thermal insulating fiber reinforced foam concretes of non-autoclaved hardening of brand D600 with regard to mean density with the following improved properties: compressive strength increased by 35% compared to basic samples, higher stability of foamed concrete mix and decreased shrinkage deformation.

  14. Chemical Modification Effect on the Mechanical Properties of Coir Fiber

    Directory of Open Access Journals (Sweden)

    Samia Sultana Mir

    2012-04-01

    Full Text Available Natural fiber has a vital role as a reinforcing agent due to its renewable, low cost, biodegradable, less abrasive and eco-friendly nature. Whereas synthetic fibers like glass, boron, carbon, metallic, ceramic and inorganic fibers are expensive and not eco-friendly. Coir is one of the natural fibers easily available in Bangladesh and cheap. It is derived from the husk of the coconut (Cocos nucifera. Coir has one of the highest concentrations of lignin, which makes it stronger. In recent years, wide range of research has been carried out on fiber reinforced polymer composites [4-13].The aim of the present research is to characterize brown single coir fiber for manufacturing polymer composites reinforced with characterized fibers. Adhesion between the fiber and polymer is one of factors affecting the strength of manufactured composites. In order to increase the adhesion, the coir fiber was chemically treated separately in single stage (with Cr2(SO43•12(H2O and double stages (with CrSO4 and NaHCO3. Both the raw and treated fibers were characterized by tensile testing, Fourier transform infrared (FTIR spectroscopic analysis, scanning electron microscopic analysis. The result showed that the Young’s modulus increased, while tensile strength and strain to failure decreased with increase in span length. Tensile properties of chemically treated coir fiber was found higher than raw coir fiber, while the double stage treated coir fiber had better mechanical properties compared to the single stage treated coir fiber. Scanning electron micrographs showed rougher surface in case of the raw coir fiber. The surface was found clean and smooth in case of the treated coir fiber. Thus the performance of coir fiber composites in industrial application can be improved by chemical treatment.

  15. Ultrahigh speed endoscopic optical coherence tomography for gastroenterology.

    Science.gov (United States)

    Tsai, Tsung-Han; Lee, Hsiang-Chieh; Ahsen, Osman O; Liang, Kaicheng; Giacomelli, Michael G; Potsaid, Benjamin M; Tao, Yuankai K; Jayaraman, Vijaysekhar; Figueiredo, Marisa; Huang, Qin; Cable, Alex E; Fujimoto, James; Mashimo, Hiroshi

    2014-12-01

    We describe an ultrahigh speed endoscopic swept source optical coherence tomography (OCT) system for clinical gastroenterology using a vertical-cavity surface-emitting laser (VCSEL) and micromotor imaging catheter. The system had a 600 kHz axial scan rate and 8 µm axial resolution in tissue. Imaging was performed with a 3.2 mm diameter imaging catheter at 400 frames per second with a 12 µm spot size. Three-dimensional OCT (3D-OCT) imaging was performed in patients with a cross section of pathologies undergoing upper and lower endoscopy. The use of distally actuated imaging catheters enabled OCT imaging with more flexibility, such as volumetric imaging in the small intestine and the assessment of hiatal hernia using retroflex imaging. The high rotational scanning stability of the micromotor enabled 3D volumetric imaging with micron scale volumetric accuracy for both en face OCT and cross-sectional imaging, as well as OCT angiography (OCTA) for 3D visualization of subsurface microvasculature. The ability to perform both structural and functional 3D OCT imaging in the GI tract with microscopic accuracy should enable a wide range of studies and enhance the sensitivity and specificity of OCT for detecting pathology.

  16. Contrast-enhanced endoscopic ultrasonography in digestive diseases.

    Science.gov (United States)

    Hirooka, Yoshiki; Itoh, Akihiro; Kawashima, Hiroki; Ohno, Eizaburo; Itoh, Yuya; Nakamura, Yosuke; Hiramatsu, Takeshi; Sugimoto, Hiroyuki; Sumi, Hajime; Hayashi, Daijiro; Ohmiya, Naoki; Miyahara, Ryoji; Nakamura, Masanao; Funasaka, Kohei; Ishigami, Masatoshi; Katano, Yoshiaki; Goto, Hidemi

    2012-10-01

    Contrast-enhanced endoscopic ultrasonography (CE-EUS) was introduced in the early 1990s. The concept of the injection of carbon dioxide microbubbles into the hepatic artery as a contrast material (enhanced ultrasonography) led to "endoscopic ultrasonographic angiography". After the arrival of the first-generation contrast agent, high-frequency (12 MHz) EUS brought about the enhancement of EUS images in the diagnosis of pancreatico-biliary diseases, upper gastrointestinal (GI) cancer, and submucosal tumors. The electronic scanning endosonoscope with both radial and linear probes enabled the use of high-end ultrasound machines and depicted the enhancement of both color/power Doppler flow-based imaging and harmonic-based imaging using second-generation contrast agents. Many reports have described the usefulness of the differential diagnosis of pancreatic diseases and other abdominal lesions. Quantitative evaluation of CE-EUS images was an objective method of diagnosis using the time-intensity curve (TIC), but it was limited to the region of interest. Recently developed Inflow Time Mapping™ can be generated from stored clips and used to display the pattern of signal enhancement with time after injection, offering temporal difference of contrast agents and improved tumor characterization. On the other hand, three-dimensional CE-EUS images added new information to the literature, but lacked positional information. Three-dimensional CE-EUS with accurate positional information is awaited. To date, most reports have been related to pancreatic lesions or lymph nodes. Hemodynamic analysis might be of use for diseases in other organs: upper GI cancer diagnosis, submucosal tumors, and biliary disorders, and it might also provide functional information. Studies of CE-EUS in diseases in many other organs will increase in the near future.

  17. Performance and safety of holmium: YAG laser optical fibers.

    Science.gov (United States)

    Knudsen, Bodo E; Glickman, Randolph D; Stallman, Kenneth J; Maswadi, Saher; Chew, Ben H; Beiko, Darren T; Denstedt, John D; Teichman, Joel M H

    2005-11-01

    Lower-pole ureteronephroscopy requires transmission of holmium:YAG energy along a deflected fiber. Current ureteroscopes are capable of high degrees of deflection, which may stress laser fibers beyond safe limits during lower-pole use. We hypothesized that optical fiber and safety measures differ among manufacturers. Small (200-273-microm) and medium-diameter (300-400-microm) Ho:YAG fibers were tested in a straight and 180 degrees bent configuration. Energy transmission was measured by an energy detector. Fiber durability was assessed by firing the laser in sequentially tighter bending diameters. The fibers were bent to 180 degrees with a diameter of 6 cm and run at 200- to 4000-mJ pulse energy to determine the minimum energy required to fracture the fiber. The bending diameter was decreased by 1-cm increments and testing repeated until a bending diameter of 1 cm was reached. The maximum deflection of the ACMI DUR-8E ureteroscope with each fiber in the working channel was recorded. The flow rate through the working channel of the DUR-8E was measured for each fiber. The mean energy transmission differed among fibers (P < 0.001). The Lumenis SL 200 and the InnovaQuartz 400 were the best small and medium-diameter fibers, respectively, in resisting thermal breakdown (P < 0.01). The Dornier Lightguide Super 200 fractured repeatedly at a bend diameter of 2 cm and with the lowest energy (200 mJ). The other small fibers fractured only at a bend diameter of 1 cm. The Sharplan 200 and InnovaQuartz Sureflex 273T were the most flexible fibers, the Lumenis SL 365 the least. The flow rate was inversely proportional to four times the power of the diameter of the fiber. Optical performance and safety differ among fibers. Fibers transmit various amounts of energy to their cladding when bent. During lower-pole nephroscopy with the fiber deflected, there is a risk of fiber fracture from thermal breakdown and laser-energy transmission to the endoscope. Some available laser fibers

  18. Endoscopic management of biliary injuries and leaks

    Directory of Open Access Journals (Sweden)

    T S Chandrasekar

    2012-01-01

    Full Text Available Bile duct injuries and subsequent leaks can occur following laparoscopic and open cholecystectomies and also during other hepatobiliary surgeries. Various patient related and technical factors are implicated in the causation of biliary injuries. Over a period of twenty five years managing such patients of biliary injuries our team has found a practical approach to assess the cause of biliary injuries based on the symptoms, clinical examination and imaging. Bismuth classification is helpful in most of the cases. Immediate referral to a centre experienced in the management of bile duct injury and timely intervention is associated with improved outcomes. Resuscitation, correcting dyselectrolytemia, aspiration of undrained biloma and antibiotics take the priority in the management. The goal is to restore the bile conduit, and to prevent short and longterm complications such as biliary fistula, intra-abdominal abscess, biliary stricture, recurrent cholangitis and secondary biliary cirrhosis. Endoscopic therapy by reducing the transpapillary pressure gradient helps in reducing the leak. Endoscopic therapy with biliary sphincterotomy alone or with additional placement of a biliary stent/ nasobiliary drainage is advocated. In our tertiary care referral unit, we found endoscopic interventions are useful in situations where there is leak with associated CBD calculus or a foreign body, peripheral bile duct injury, cystic duct stump leak and partial bile duct injury with leak/ narrowing of the lumen. Endotherapy is not useful in case of complete transection (total cut off and complete stricture involving common hepatic or common bile ducts. In conclusion, endoscopic treatment can be considered a highly effective therapy and should be the first-line therapy in such patients. Though less successful, an endoscopic attempt is warranted in patients suffering from central bile duct leakages failing which surgical management is recommended.

  19. Endoscopic sleeve gastroplasty: the learning curve.

    Science.gov (United States)

    Hill, Christine; El Zein, Mohamad; Agnihotri, Abhishek; Dunlap, Margo; Chang, Angela; Agrawal, Alison; Barola, Sindhu; Ngamruengphong, Saowanee; Chen, Yen-I; Kalloo, Anthony N; Khashab, Mouen A; Kumbhari, Vivek

    2017-09-01

    Endoscopic sleeve gastroplasty (ESG) is gaining traction as a minimally invasive bariatric treatment. Concern that the learning curve may be slow, even among those proficient in endoscopic suturing, is a barrier to widespread implementation of the procedure. Therefore, we aimed to define the learning curve for ESG in a single endoscopist experienced in endoscopic suturing who participated in a 1-day ESG training program.  Consecutive patients who underwent ESG between February 2016 and November 2016 were included. The performing endoscopist, who is proficient in endoscopic suturing for non-ESG procedures, participated in a 1-day ESG training session before offering ESG to patients. The outcome measurements were length of procedure (LOP) and number of plications per procedure. Nonlinear regression was used to determine the learning plateau and calculate the learning rate.  Twenty-one consecutive patients (8 males), with mean age 47.7 ± 11.2 years and mean body mass index 41.8 ± 8.5 kg/m 2 underwent ESG. LOP decreased significantly across consecutive procedures, with a learning plateau at 101.5 minutes and a learning rate of 7 cases ( P  = 0.04). The number of plications per procedure also decreased significantly across consecutive procedures, with a plateau at 8 sutures and a learning rate of 9 cases ( P  < 0.001). Further, the average time per plication decreased significantly with consecutive procedures, reaching a plateau at 9 procedures ( P  < 0.001).  Endoscopists experienced in endoscopic suturing are expected to achieve a reduction in LOP and number of plications per procedure in successive cases, with progress plateauing at 7 and 9 cases, respectively.

  20. Update on endoscopic pancreatic function testing

    Institute of Scientific and Technical Information of China (English)

    Tyler Stevens; Mansour A Parsi

    2011-01-01

    Hormone-stimulated pancreatic function tests (PFTs) are considered the gold standard for measuring pancreatic exocrine function. PFTs involve the administration of intravenous secretin or cholecystokinin, followed by collection and analysis of pancreatic secretions. Because exocrine function may decline in the earliest phase of pancreatic fibrosis, PFTs are considered accurate for diagnosing chronic pancreatitis. Unfortunately, these potentially valuable tests are infrequently performed except at specialized centers, because they are time consuming and complicated. To overcome these limitations, endoscopic PFT methods have been developed which include aspiration of pancreatic secretions through the suction channel of the endoscope. The secretin endoscopic pancreatic function test (ePFT) involves collection of duodenal aspirates at 15, 30, 45 and 60 min after secretin stimulation. A bicarbonate concentration greater than 80 mmol/L in any of the samples is considered a normal result. The secretin ePFT has demonstrated good sensitivity and specificity compared with various reference standards, including the "Dreiling tube" secretin PFT, endoscopic ultrasound, and surgical histology. Furthermore, a standard autoanalyzer can be used for bicarbonate analysis, which allows the secretin ePFT to be performed at any hospital. The secretin ePFT may complement imaging tests like endoscopic ultrasound (EUS) in the diagnosis of early chronic pancreatitis.This paper will review the literature validating the use of ePFT in the diagnosis of exocrine insufficiency and chronic pancreatitis. Newer developments will also be discussed, including the feasibility of combined EUS/ePFT, the use of cholecystokinin alone or in combination with secretin, and the discovery of new protein and lipid pancreatic juice biomarkers which may complement traditionalfluid analysis.

  1. Radiological findings after endoscopic incision of ureterocele

    International Nuclear Information System (INIS)

    Cheon, Jung Eun; Kim, In One; Seok, Eul Hye; Cha, Joo Hee; Choi, Gook Myung; Kim, Woo Sun; Yeon, Kyung Mo; Kim, Kwang Myung; Choi, Hwang; Cheon, Jung Eun; Seok, Eul Hye; Cha, Joo Hee; Choi, Guk Myung

    2001-01-01

    Endoscopic incision of ureterocele is considered a simple and safe method for decompression of urinary tract obstruction above ureterocele. The purpose of this study was to evaluate the radiological findings after endoscopic incision of ureterocele. We retrospectively reviewed the radiological findings (ultrasonography (US), intravenous urography, and voiding cystourethrography(VCU)) in 16 patients with ureterocele who underwent endoscopic incision (mean age at surgery, 15 months; M:F 3:13; 18 ureteroceles). According to the postoperative results, treatment was classified as successful when medical treatment was still required, and second operation when additional surgical treatment was required. Postoperative US (n=10) showed that in all patients, urinary tract obstruction was relieved: the kidney parenchima was thicker and the ureterocele was smaller. Intravenous urography (n=8), demonstrated that in all patients, urinary tract obstruction and the excretory function of the kidney had improved. Postoperative VCU indicated that in 92% of patients (12 of 13), endoscopic incision of the ureterocele led to vesicoureteral reflux(VUR). Of these twelve, seven (58%) showed VUR of more than grade 3, while newly developed VUR was seen in five of eight patients (63%) who had preoperative VCU. Surgery was successful in four patients (25%), partially successful in three (19%), and a second operation-on account of recurrent urinary tract infection and VUR of more than grase 3 during the follow-up period-was required by nine (56%). Although endoscopic incision of a ureterocele is a useful way of relieving urinary tract obstruction, an ensuing complication may be VUR. Postoperative US and intravenous urography should be used to evaluate parenchymal change in the kidney and improvement of uronary tract obstructon, while to assess the extend of VUR during the follow-up period , postoperative VCU is required

  2. Carbon nanotube and graphene nanoribbon-coated conductive Kevlar fibers.

    Science.gov (United States)

    Xiang, Changsheng; Lu, Wei; Zhu, Yu; Sun, Zhengzong; Yan, Zheng; Hwang, Chi-Chau; Tour, James M

    2012-01-01

    Conductive carbon material-coated Kevlar fibers were fabricated through layer-by-layer spray coating. Polyurethane was used as the interlayer between the Kevlar fiber and carbon materials to bind the carbon materials to the Kevlar fiber. Strongly adhering single-walled carbon nanotube coatings yielded a durable conductivity of 65 S/cm without significant mechanical degradation. In addition, the properties remained stable after bending or water washing cycles. The coated fibers were analyzed using scanning electron microcopy and a knot test. The as-produced fiber had a knot efficiency of 23%, which is more than four times higher than that of carbon fibers. The spray-coating of graphene nanoribbons onto Kevlar fibers was also investigated. These flexible coated-Kevlar fibers have the potential to be used for conductive wires in wearable electronics and battery-heated armors. © 2011 American Chemical Society

  3. Biosoftening of coir fiber using selected microorganisms.

    Science.gov (United States)

    Rajan, Akhila; Senan, Resmi C; Pavithran, C; Abraham, T Emilia

    2005-12-01

    Coir fiber belongs to the group of hard structural fibers obtained from coconut husk. As lignin is the main constituent of coir responsible for its stiffness, microbes that selectively remove lignin without loss of appreciable amounts of cellulose are extremely attractive in biosoftening. Five isolated strains were compared with known strains of bacteria and fungi. The raw fiber treated with Pseudomonas putida and Phanerocheate chrysosporium produced better softened fiber at 30+/-2 degrees C and neutral pH. FeSO4 and humic acid were found to be the best inducers for P. chrysosporium and P. putida, respectively, while sucrose and dextrose were the best C-sources for both. Biosoftening of unretted coir fibers was more advantageous than the retted fibers. Unlike the weak chemically softened fiber, microbial treatment produced soft, whiter fibers having better tensile strength and elongation (44.6-44.8%) properties. Scanning electron microscopy photos showed the mycelia penetrating the pores of the fiber, removing the tylose plug and degrading lignin.

  4. Application Specific Optical Fibers

    OpenAIRE

    Pal, Bishnu P.

    2010-01-01

    In this chapter we have attempted to provide a unified summary description of the most important propagation characteristics of an optical fiber followed by discussion on several variety of special fibers for realizing fiber amplifiers, dispersion compensating fibers, microstructured optical fibers, and so on. Even though huge progress has been made on development of optical fibers for telecom application, a need for developing special fibers, not necessarily for telecom alone, has arisen. Th...

  5. Colloid-templated multisectional porous polymeric fibers.

    Science.gov (United States)

    Song, Jung Hun; Kretzschmar, Ilona

    2008-10-07

    A fabrication method for porous polymeric fibers (PPFs) is reported. We show that a multisectional colloidal crystal can be assembled within a microcapillary by alternating dipping into colloidal solutions of varying size. Subsequent infiltration with curable polymer and washing with suitable solvents results in porous fibers with a cylindrical cross section. Along the length of the fiber, alternating sections of controlled length, pore size, and pore size distribution exist. These fibers present interesting materials for neural scaffolding, catalysis, and possibly photonics if produced with a high degree of crystallinity. The surface pores and bulk porosity of the fibers are characterized by variable-pressure scanning electron microscopy (vp-SEM). Careful analysis shows that the surface pores vary with the colloidal template diameter and polymer infiltration time.

  6. Influence of fiber length on flexural and impact properties of Zalacca Midrib fiber/HDPE by compression molding

    Science.gov (United States)

    Pamungkas, Agil Fitri; Ariawan, Dody; Surojo, Eko; Triyono, Joko

    2018-02-01

    The aim of the research is to investigate the effect of fiber length on the flexural and impact properties of the composite of Zalacca Midrib Fiber (ZMF)/HDPE. The process of making composite was using compression molding method. The variation of fiber length were 1 mm, 3 mm, 5 mm, 7 mm and 9 mm, at 30% fiber volume fraction. The flexural and impact test according to ASTM D790 and ASTM D5941, respectively. Observing fracture surface was examained by using Scanning Electron Microscopy (SEM). The results showed that the flexural and impact strengths would be increase with the increase of fiber length.

  7. Análise de Fourier para detecção de defeitos localizados na camada de fibras nervosas da retina com a polarimetria a laser Fourier analysis for the detection of localized nerve fiber layer defects using scanning laser polarimetry

    Directory of Open Access Journals (Sweden)

    Felipe Andrade Medeiros

    2003-12-01

    this study, we performed Fourier analysis of retinal nerve fiber layer (RNFL thickness measurements obtained with scanning laser polarimetry and evaluated the ability of this method to detect localized nerve fiber layer defects in glaucomatous patients. METHODS: The study included 40 eyes of 40 glaucomatous patients with localized RNFL defects identified by slit-lamp biomicroscopy or RNFL photography and 43 eyes of 43 normal patients. The patients were submitted to RNFL thickness measurements using the GDx® - Nerve Fiber Analyzer. Fourier analysis was applied to the polarimetry data. Fourier coefficients and GDx parameters were compared between the two groups. A linear discriminant function was developed to identify and combine the most useful Fourier coefficients to separate the two groups. ROC curves were obtained for each measurement and sensitivity values (at fixed specificities were calculated. RESULTS: The combination of Fourier coefficients resulted in a sensitivity of 80% for a specificity set at higher than 90%. For the same specificity, the GDx parameters had sensitivities ranging from 15% to 48%. The area under the ROC curve (AUC for the combination of Fourier coefficients was 0.90, significantly higher than the AUC for the parameter The Number (0.76. CONCLUSION: Fourier analysis of RNFL polarimetry data had a better diagnostic performance than standard GDx parameters to identify localized retinal nerve fiber layer defects in glaucomatous patients.

  8. Scaffolds of polycaprolactone with hydroxyapatite fibers

    International Nuclear Information System (INIS)

    Cardoso, Guinea B.C.; Zavaglia, Cecilia A.C.; Arruda, Antonio Celso F.

    2009-01-01

    Scaffolds of poly (ε-caprolactone) has been studied in many researches in tissue engineering. The used of hydroxyapatite fibers, allowed increase its resistance mechanical, beside the character bioactive and osteoconductive. Improving, its role in tissue engineering. The aim in this study was developed polycaprolactone matrix with dispersed hydroxyapatite fibers. The characterizations were by scanning electron microscopy (SEM), X- Ray Diffractometer (XRD), X-Ray Fluorescence (XRF) and Energy dispersive X-Ray Detector (EDX). Was able reviewed its composition, morphology and possible contaminations. The results were scaffolds with porosity and distribution of the fibers in all its area. (author)

  9. Engineering aspects of a fully mirrored endoscope

    International Nuclear Information System (INIS)

    Terra, A.; Huber, A.; Schweer, B.; Mertens, Ph.; Arnoux, G.; Balshaw, N.; Brezinsek, S.; Egner, S.; Hartl, M.; Kampf, D.; Klammer, J.; Lambertz, H.T.; Morlock, C.; Murari, A.; Reindl, M.; Sanders, S.; Sergienko, G.; Spencer, G.

    2013-01-01

    Highlights: ► Replacement of JET diagnostics to match the new ITER-like Wall. ► The endoscope test ITER-like design with only mirror based optics. ► Withstanding and diagnostic capability during Plasma operation and disruptions. ► Engineering process from design to installation and procurement. -- Abstract: The development of optical diagnostics, like endoscopes, compatible with the ITER environment (metallic plasma facing components, neutron proof optics, etc.) is a challenge, but current tokamaks such as JET provide opportunities to test fully working concepts. This paper describes the engineering aspects of a fully mirrored endoscope that has recently been designed, procured and installed on JET. The system must operate in a very strict environment with high temperature, high magnetic fields up to B = 4 T and rapid field variations (∂B/∂t ∼ 100 T/s) that induce high stresses due to eddy currents in the front mirror assembly. It must be designed to withstand high mechanical loads especially during disruptions, which lead to acceleration of about 7 g at 14 Hz. For the JET endoscope, when the plasma thermal loading, direct and indirect, was added to the assumed disruption loads, the reserve factor, defined as a ratio of yield strength over summed up von Mises stresses, was close to 1 for the mirror components. To ensure reliable operation, several analyses were performed to evaluate the thermo-mechanical performance of the endoscope and a final validation was obtained from mechanical and thermal tests, before the system's final installation in May 2011. During the tests, stability of the field of view angle variation was kept below 1° despite the high thermal gradient on endoscope head (∂T/∂x ∼ 500 K/m). In parallel, to ensure long time operation and to prevent undesirable performance degradation, a shutter system was also implemented in order to reduce impurity deposition on in-vessel mirrors but also to allow in situ transmission calibration

  10. Physicochemical properties of surimi gels fortified with dietary fiber.

    Science.gov (United States)

    Debusca, Alicia; Tahergorabi, Reza; Beamer, Sarah K; Matak, Kristen E; Jaczynski, Jacek

    2014-04-01

    Although dietary fiber provides health benefits, most Western populations have insufficient intake. Surimi seafood is not currently fortified with dietary fiber, nor have the effects of fiber fortification on physicochemical properties of surimi been thoroughly studied. In the present study, Alaska pollock surimi was fortified with 0-8 g/100 g of long-chain powdered cellulose as a source of dietary fiber. The protein/water concentrations in surimi were kept constant by adding an inert filler, silicon dioxide in inverse concentrations to the fiber fortification. Fiber-fortified surimi gels were set at 90 °C. The objectives were to determine (1) textural and colour properties; (2) heat-induced gelation (dynamic rheology); and (3) protein endothermic transitions (differential scanning calorimetry) of surimi formulated with constant protein/water, but variable fiber content. Fiber fortification up to 6 g/100 g improved (Pfiber. Dynamic rheology correlated with texture and showed large increase in gel elasticity, indicating enhanced thermal gelation of surimi. Differential scanning calorimetry showed that fiber fortification did not interfere with thermal transitions of surimi myosin and actin. Long-chain fiber probably traps water physically, which is stabilized by chemical bonding with protein within surimi gel matrix. Based on the present study, it is suggested that the fiber-protein interaction is mediated by water and is physicochemical in nature. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. endoscope-i: an innovation in mobile endoscopic technology transforming the delivery of patient care in otolaryngology.

    Science.gov (United States)

    Mistry, N; Coulson, C; George, A

    2017-11-01

    Digital and mobile device technology in healthcare is a growing market. The introduction of the endoscope-i, the world's first endoscopic mobile imaging system, allows the acquisition of high definition images of the ear, nose and throat (ENT). The system combines the e-i Pro camera app with a bespoke engineered endoscope-i adaptor which fits securely onto the iPhone or iPod touch. Endoscopic examination forms a salient aspect of the ENT work-up. The endoscope-i therefore provides a mobile and compact alternative to the existing bulky endoscopic systems currently in use which often restrict the clinician to the clinic setting. Areas covered: This article gives a detailed overview of the endoscope-i system together with its applications. A review and comparison of alternative devices on the market offering smartphone adapted endoscopic viewing systems is also presented. Expert commentary: The endoscope-i fulfils unmet needs by providing a compact, highly portable, simple to use endoscopic viewing system which is cost-effective and which makes use of smartphone technology most clinicians have in their pocket. The system allows real-time feedback to the patient and has the potential to transform the way that healthcare is delivered in ENT as well as having applications further afield.

  12. Tensile responses of treated Cissus populnea fibers | Azeez ...

    African Journals Online (AJOL)

    acetic acid (EDTA), respectively, were used for fiber treatment and optimi zed with variable parameters (concentration and time) using response surface methodology (RSM) with central composite design. Scanning electron microscopy (SEM) with ...

  13. Gynaecological Endoscopic Surgical Education and Assessment. A diploma programme in gynaecological endoscopic surgery.

    Science.gov (United States)

    Campo, Rudi; Wattiez, Arnaud; Tanos, Vasilis; Di Spiezio Sardo, Attilio; Grimbizis, Grigoris; Wallwiener, Diethelm; Brucker, Sara; Puga, Marco; Molinas, Roger; O'Donovan, Peter; Deprest, Jan; Van Belle, Yves; Lissens, Ann; Herrmann, Anja; Tahir, Mahmood; Benedetto, Chiara; Siebert, Igno; Rabischong, Benoit; De Wilde, Rudy Leon

    2016-04-01

    In recent years, training and education in endoscopic surgery has been critically reviewed. Clinicians, both surgeons as gynaecologist who perform endoscopic surgery without proper training of the specific psychomotor skills are at higher risk to increased patient morbidity and mortality. Although the apprentice-tutor model has long been a successful approach for training of surgeons, recently, clinicians have recognised that endoscopic surgery requires an important training phase outside the operating theatre. The Gynaecological Endoscopic Surgical Education and Assessment programme (GESEA), recognises the necessity of this structured approach and implements two separated stages in its learning strategy. In the first stage, a skill certificate on theoretical knowledge and specific practical psychomotor skills is acquired through a high stake exam; in the second stage, a clinical programme is completed to achieve surgical competence and receive the corresponding diploma. Three diplomas can be awarded: (a) the Bachelor in Endoscopy; (b) the Minimally Invasive Gynaecological Surgeon (MIGS); and (c) the Master level. The Master level is sub-divided into two separate diplomas: the Master in Laparoscopic Pelvic Surgery and the Master in Hysteroscopy. The complexity of modern surgery has increased the demands and challenges to surgical education and the quality control. This programme is based on the best available scientific evidence and it counteracts the problem of the traditional surgical apprentice tutor model. It is seen as a major step toward standardization of endoscopic surgical training in general. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. Scanning laser polarimetry in glaucoma.

    Science.gov (United States)

    Dada, Tanuj; Sharma, Reetika; Angmo, Dewang; Sinha, Gautam; Bhartiya, Shibal; Mishra, Sanjay K; Panda, Anita; Sihota, Ramanjit

    2014-11-01

    Glaucoma is an acquired progressive optic neuropathy which is characterized by changes in the optic nerve head and retinal nerve fiber layer (RNFL). White-on-white perimetry is the gold standard for the diagnosis of glaucoma. However, it can detect defects in the visual field only after the loss of as many as 40% of the ganglion cells. Hence, the measurement of RNFL thickness has come up. Optical coherence tomography and scanning laser polarimetry (SLP) are the techniques that utilize the evaluation of RNFL for the evaluation of glaucoma. SLP provides RNFL thickness measurements based upon the birefringence of the retinal ganglion cell axons. We have reviewed the published literature on the use of SLP in glaucoma. This review elucidates the technological principles, recent developments and the role of SLP in the diagnosis and monitoring of glaucomatous optic neuropathy, in the light of scientific evidence so far.

  15. Characterization of ecofriendly polyethylene fiber from plastic bag waste

    Science.gov (United States)

    Soekoco, Asril S.; Noerati, Komalasari, Maya; Kurniawan, Hananto, Agus

    2017-08-01

    This paper presents the characterization of fiber morphology, fiber count and tenacity of polyethylene fiber which is made from plastic bag waste. Recycling plastic bag waste into textile fiber has not developed yet. Plastic bag waste was recycled into fiber by melt spinning using laboratory scale melt spinning equipment with single orifice nozzle and plunger system. The basic principle of melt spinning is by melting materials and then extruding it through small orifice of a spinning nozzle to form fibers. Diameter and cross section shape of Recycled polyethylene fiber were obtained by using scanning electron microscope (SEM) instrumentation. Linear density of the recycled fiber were analyzed by calculation using denier and dTex formulation and The mechanical strength of the fibers was measured in accordance with the ASTM D 3379-75 standard. The cross section of recycled fiber is circular taking the shape of orifice. Fiber count of 303.75 denier has 1.84 g/denier tenacity and fiber count of 32.52 has 3.44 g/denier tenacity. This conditions is affected by the growth of polymer chain alignment when take-up axial velocity become faster. Recycled polyethylene fiber has a great potential application in non-apparel textile.

  16. The effect of neutron irradiation on silicon carbide fibers

    International Nuclear Information System (INIS)

    Newsome, G.A.

    1997-01-01

    Nine types of SiC fiber have been exposed to neutron radiation in the Advanced Test Reactor at 250 C for various lengths of time ranging from 83 to 128 days. The effects of these exposures have been initially determined using scanning electron microscopy. The fibers tested were Nicalon trademark CG, Tyranno, Hi-Nicalon trademark, Dow Corning SiC, Carborundum SiC, Textron SCS-6, polymethysilane (PMS) derived SiC from the University of Michigan, and two types of MER SiC fiber. This covers a range of fibers from widely used commercial fibers to developmental fibers. Consistent with previous radiation experiments, Nicalon fiber was severely degraded by the neutron irradiation. Similarly, Tyranno suffered severe degradation. The more advanced fibers which approach the composition and properties of SiC performed well under irradiation. Of these, the Carborundum SiC fiber appeared to perform the best. The Hi-Nicalon and Dow Corning Fibers exhibited good general stability, but also appear to have some surface roughening. The MER fibers and the Textron SCS-6 fibers both had carbon cores which adversely influenced the overall stability of the fibers

  17. Devices and Endoscopic Bariatric Therapies for Obesity.

    Science.gov (United States)

    Saunders, Katherine H; Igel, Leon I; Saumoy, Monica; Sharaiha, Reem Z; Aronne, Louis J

    2018-04-17

    In this review, we describe the FDA-approved and investigational devices and endoscopic bariatric therapies for the treatment of obesity. We focus on literature published in the past few years and present mechanisms of action as well as efficacy and safety data. Devices and endoscopic procedures are emerging options to fill the significant treatment gap in the management of obesity. Not only are these devices and procedures minimally invasive and reversible, but they are potentially more effective than antiobesity medications, often safer for poor surgical candidates and possibly less expensive than bariatric surgery. As many patients require a variety of management strategies (medications, devices, procedures, and/or surgery) in addition to lifestyle modifications to achieve clinically significant weight loss, the future of obesity treatment involves a multidisciplinary approach. Combinations of advanced treatment strategies can lead to additive or synergistic weight loss. This is an area that requires further investigation.

  18. Fundus imaging with a nasal endoscope

    Directory of Open Access Journals (Sweden)

    P Mahesh Shanmugam

    2015-01-01

    Full Text Available Wide field fundus imaging is needed to diagnose, treat, and follow-up patients with retinal pathology. This is more applicable for pediatric patients as repeated evaluation is a challenge. The presently available imaging machines though provide high definition images, but carry the obvious disadvantages of either being costly or bulky or sometimes both, which limits its usage only to large centers. We hereby report a technique of fundus imaging using a nasal endoscope coupled with viscoelastic. A regular nasal endoscope with viscoelastic coupling was placed on the cornea to image the fundus of infants under general anesthesia. Wide angle fundus images of various fundus pathologies in infants could be obtained easily with readily available instruments and without the much financial investment for the institutes.

  19. Emerging indications of endoscopic radiofrequency ablation

    Science.gov (United States)

    Becq, Aymeric; Camus, Marine; Rahmi, Gabriel; de Parades, Vincent; Marteau, Philippe

    2015-01-01

    Introduction Radiofrequency ablation (RFA) is a well-validated treatment of dysplastic Barrett's esophagus. Other indications of endoscopic RFA are under evaluation. Results Four prospective studies (total 69 patients) have shown that RFA achieved complete remission of early esophageal squamous intra-epithelial neoplasia at a rate of 80%, but with a substantial risk of stricture. In the setting of gastric antral vascular ectasia, two prospective monocenter studies, and a retrospective multicenter study, (total 51 patients), suggest that RFA is efficacious in terms of reducing transfusion dependency. In the setting of chronic hemorrhagic radiation proctopathy, a prospective monocenter study and a retrospective multicenter study (total 56 patients) suggest that RFA is an efficient treatment. A retrospective comparative study (64 patients) suggests that RFA improves stents patency in malignant biliary strictures. Conclusions Endoscopic RFA is an upcoming treatment modality in early esophageal squamous intra-epithelial neoplasia, as well as in gastric, rectal, and biliary diseases. PMID:26279839

  20. Endoscopic treatment of large vesical calculi

    International Nuclear Information System (INIS)

    Rauf, A.; Ahmed, I.; Rauf, M.H.; Rauf, M.

    2015-01-01

    Objective: To determine the efficiency and safety of endoscopic treatment of large vesical calculi with the available modern endoscopic instruments. Methology: In case series, patients were collected randomly from 2007 to 2014. Patients were diagnosed with ultrasound and Nephroscope with Swiss pneumatic lithoclast, lithotrite and stone punch were used for treatment. Results: Majority of the patient could be managed with the method adopted. Stone size, hardness or softness, gender were the factors affecting treatment. Associated prostate pathology was seen in four patients. Postoperative complications included hemorrhage, perforation, residual stone and transurethral resection of prostate syndrome. Conclusion: Overall, it is a safe procedure except in patients with large enlarged prostate and large vesical calculi. Very hard vesical calculus may need vesicolithotomy. (author)

  1. Comprehensive review on endonasal endoscopic sinus surgery

    Science.gov (United States)

    Weber, Rainer K.; Hosemann, Werner

    2015-01-01

    Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3–4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment. PMID:26770282

  2. Counter traction makes endoscopic submucosal dissection easier.

    Science.gov (United States)

    Oyama, Tsuneo

    2012-11-01

    Poor counter traction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Good counter traction allows dissections to be performed more quickly and safely. Position change, which utilizes gravity, is the simplest method to create a clear field of vision. It is useful especially for esophageal and colon ESD. The second easiest method is clip with line method. Counter traction made by clip with line accomplishes the creation of a clear field of vision and suitable counter traction thereby making ESD more efficient and safe. The author published this method in 2002. The name ESD was not established in those days; the name cutting endoscopic mucosal resection (EMR) or EMR with hook knife was used. The other traction methods such as external grasping forceps, internal traction, double channel scope, and double scopes method are introduced in this paper. A good strategy for creating counter traction makes ESD easier.

  3. Endoscopic therapy for Barrett′s esophagus

    Directory of Open Access Journals (Sweden)

    Nicholas J Shaheen

    2012-01-01

    Full Text Available Barrett′s esophagus (BE is the precursor lesion to esophageal adenocarcinoma. This cancer has undergone a rapid increase in incidence in Western societies in the last 30 years. Current practices seek to lower the risk of death from this cancer by performing screening upper endoscopy on those with chronic reflux symptoms, and then surveillance upper endoscopy on those found to have BE at periodic intervals. While this approach is intuitively appealing, no data substantiate a decreased cancer risk with these practices, and substantial issues limit the effectiveness of this approach. This article outlines the current approaches to BE, their shortcomings, and presents data supporting the use of endoscopic therapy for subjects with BE and dysplasia. A significant and growing literature supports the use of endoscopic therapy in BE, and this approach, combined with improved risk stratification, may improve our care of subjects with BE.

  4. Endoscopic Sphincterotomy Using the Rendezvous Technique for Choledocholithiasis during Laparoscopic Cholecystectomy: A Case Report.

    Science.gov (United States)

    Tanaka, Takayuki; Haraguchi, Masashi; Tokai, Hirotaka; Ito, Shinichiro; Kitajima, Masachika; Ohno, Tsuyoshi; Onizuka, Shinya; Inoue, Keiji; Motoyoshi, Yasuhide; Kuroki, Tamotsu; Kanemastu, Takashi; Eguchi, Susumu

    2014-05-01

    A 50-year-old male was examined at another hospital for fever, general fatigue and slight abdominal pain. He was treated with antibiotics and observed. However, his symptoms did not lessen, and laboratory tests revealed liver dysfunction, jaundice and an increased inflammatory response. He was then admitted to our hospital and underwent an abdominal computed tomography scan and magnetic resonance cholangiopancreatography (MRCP), which revealed common bile duct (CBD) stones. He was diagnosed with mild acute cholangitis. As the same time, he was admitted to our hospital and an emergency endoscopic retrograde cholangiopancreatography was performed. Vater papilla opening in the third portion of the duodenum and presence of a peripapillary duodenal diverticulum made it difficult to perform cannulation of the CBD. In addition, MRCP revealed that the CBD was extremely narrow (diameter 5 mm). We therefore performed laparoscopic cholecystectomy and endoscopic sphincterotomy using the rendezvous technique for choledocholithiasis simultaneously rather than laparoscopic CBD exploration. After the operation, the patient was discharged with no complications. Although the rendezvous technique has not been very commonly used because several experts in the technique and a large operating room are required, this technique is a very attractive and effective approach for treating choledocholithiasis, for which endoscopic treatment is difficult.

  5. Endoscopic Sphincterotomy Using the Rendezvous Technique for Choledocholithiasis during Laparoscopic Cholecystectomy: A Case Report

    Directory of Open Access Journals (Sweden)

    Takayuki Tanaka

    2014-08-01

    Full Text Available A 50-year-old male was examined at another hospital for fever, general fatigue and slight abdominal pain. He was treated with antibiotics and observed. However, his symptoms did not lessen, and laboratory tests revealed liver dysfunction, jaundice and an increased inflammatory response. He was then admitted to our hospital and underwent an abdominal computed tomography scan and magnetic resonance cholangiopancreatography (MRCP, which revealed common bile duct (CBD stones. He was diagnosed with mild acute cholangitis. As the same time, he was admitted to our hospital and an emergency endoscopic retrograde cholangiopancreatography was performed. Vater papilla opening in the third portion of the duodenum and presence of a peripapillary duodenal diverticulum made it difficult to perform cannulation of the CBD. In addition, MRCP revealed that the CBD was extremely narrow (diameter 5 mm. We therefore performed laparoscopic cholecystectomy and endoscopic sphincterotomy using the rendezvous technique for choledocholithiasis simultaneously rather than laparoscopic CBD exploration. After the operation, the patient was discharged with no complications. Although the rendezvous technique has not been very commonly used because several experts in the technique and a large operating room are required, this technique is a very attractive and effective approach for treating choledocholithiasis, for which endoscopic treatment is difficult.

  6. Endoscopic surgical management of a large Morel-Lavallée lesion.

    Science.gov (United States)

    Walls, Andrew; McMahon, Samuel E; MacDonald, Jonathan; Bunn, Jonathan

    2017-09-23

    The Morel-Lavallée lesion is a closed degloving injury that usually occurs following high-energy trauma. We present a case demonstrating endoscopic management of this lesion. A 44-year-old man fell from scaffolding. Initial assessment demonstrated no significant injury. An ultrasound scan 2 days post injury revealed a large fluid collection along the lateral right thigh. This subsequently became infected and did not respond to antibiotic therapy.Due to the extent of the lesion, we were reluctant to perform a traditional open drainage. An endoscopic probe was inserted at the proximal and distal poles of the lesion and the wound debrided.This resulted in a rapid improvement in symptoms and a complete resolution of the lesion at 1 year postsurgery, with no wound-associated morbidity.This is only the second description of endoscopic debridement of a large, acute Morel-Lavallée lesion, with an excellent outcome. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Endoscopic treatment of vesicoureteral reflux in pediatric patients

    Directory of Open Access Journals (Sweden)

    Jong Wook Kim

    2013-04-01

    Full Text Available Endoscopic treatment is a minimally invasive treatment for managing patients with vesicoureteral reflux (VUR. Although several bulking agents have been used for endoscopic treatment, dextranomer/hyaluronic acid is the only bulking agent currently approved by the U.S. Food and Drug Administration for treating VUR. Endoscopic treatment of VUR has gained great popularity owing to several obvious benefits, including short operative time, short hospital stay, minimal invasiveness, high efficacy, low complication rate, and reduced cost. Initially, the success rates of endoscopic treatment have been lower than that of open antireflux surgery. However, because injection techniques have been developed, a recent study showed higher success rates of endoscopic treatment than open surgery in the treatment of patients with intermediate- and high-grade VUR. Despite the controversy surrounding its effectiveness, endoscopic treatment is considered a valuable treatment option and viable alternative to long-term antibiotic prophylaxis.

  8. Endoscopic Ultrasonography in the Diagnosis of Gastric Subepithelial Lesions

    Directory of Open Access Journals (Sweden)

    Eun Jeong Gong

    2016-09-01

    Full Text Available Subepithelial lesions occasionally found in the stomach of patients undergoing endoscopy may be either benign lesions or tumors with malignant potential. They may also appear due to extrinsic compression. Discrimination of gastric subepithelial lesions begins with meticulous endoscopic examination for size, shape, color, mobility, consistency, and appearance of the overlying mucosa. Accurate diagnosis can be achieved with endoscopic ultrasonography, which provides useful information on the exact size, layer-of-origin, and characteristic morphologic features to support a definitive diagnosis. Endoscopic ultrasonography also aids in the prediction of malignant potential, especially in gastrointestinal stromal tumors. Features of subepithelial lesions identified on endoscopic ultrasonography can be used to determine whether further diagnostic procedures such as endoscopic resection, fine needle aspiration, or core biopsy are required. Endoscopic ultrasonography is a valuable tool for diagnosis and clinical decision making during follow-up of gastric subepithelial lesions.

  9. Endoscopic versus open bursectomy of lateral malleolar bursitis.

    Science.gov (United States)

    Choi, Jae Hyuck; Lee, Kyung Tai; Lee, Young Koo; Kim, Dong Hyun; Kim, Jeong Ryoul; Chung, Woo Chull; Cha, Seung Do

    2012-06-01

    Compare the result of endoscopic versus open bursectomy in lateral malleolar bursitis. Prospective evaluation of 21 patients (22 ankles) undergoing either open or endoscopic excision of lateral malleolar bursitis. The median age was 64 (38-79) years old. The median postoperative follow-up was 15 (12-18) months. Those patients undergoing endoscopic excision showed a higher satisfaction rate (excellent 9, good 2) than open excision (excellent 4, good 3, fair 1). The wounds also healed earlier in the endoscopic group although the operation time was slightly longer. One patient in the endoscopic group had recurrence of symptoms but complications in the open group included one patient with skin necrosis, one patient with wound dehiscence, and two patients of with superficial peroneal nerve injury. Endoscopic resection of the lateral malleolar bursitis is a promising technique and shows favorable results compared to the open resection. Therapeutic studies-Investigating the result of treatment, Level II.

  10. Endoscopic Management of Tumor Bleeding from Inoperable Gastric Cancer

    Science.gov (United States)

    Kim, Young-Il

    2015-01-01

    Tumor bleeding is not a rare complication in patients with inoperable gastric cancer. Endoscopy has important roles in the diagnosis and primary treatment of tumor bleeding, similar to its roles in other non-variceal upper gastrointestinal bleeding cases. Although limited studies have been performed, endoscopic therapy has been highly successful in achieving initial hemostasis. One or a combination of endoscopic therapy modalities, such as injection therapy, mechanical therapy, or ablative therapy, can be used for hemostasis in patients with endoscopic stigmata of recent hemorrhage. However, rebleeding after successful hemostasis with endoscopic therapy frequently occurs. Endoscopic therapy may be a treatment option for successfully controlling this rebleeding. Transarterial embolization or palliative surgery should be considered when endoscopic therapy fails. For primary and secondary prevention of tumor bleeding, proton pump inhibitors can be prescribed, although their effectiveness to prevent bleeding remains to be investigated. PMID:25844339

  11. Influence of Polyaniline Coated Kenaf Fiber on Kenaf Paper Sheet

    OpenAIRE

    Abdullah Hisham Nur Syafiqah; Abd Razak Saiful Izwan; Mat Nayan Nadirul Hasraf; Wan Abdul Rahman Wan Aizan

    2015-01-01

    This paper reports the properties of newly developed electrically conductive natural fiber paper sheet made up of kenaf fiber (KF) incorporated with polyaniline coated kenaf fiber (KF-PANI). This study proposed on dispersion of conductive filler in different amount (wt %) into kenaf pulp for developing different electrical conductivity. The conductive sheet (KF/KF-PANI) revealed a percolation concentration at 25 wt% of KF-PANI. Its scanning electron micrograph showed good paper formation with...

  12. Influence of Polyaniline Coated Kenaf Fiber on Kenaf Paper Sheet

    Directory of Open Access Journals (Sweden)

    Abdullah Hisham Nur Syafiqah

    2015-01-01

    Full Text Available This paper reports the properties of newly developed electrically conductive natural fiber paper sheet made up of kenaf fiber (KF incorporated with polyaniline coated kenaf fiber (KF-PANI. This study proposed on dispersion of conductive filler in different amount (wt % into kenaf pulp for developing different electrical conductivity. The conductive sheet (KF/KF-PANI revealed a percolation concentration at 25 wt% of KF-PANI. Its scanning electron micrograph showed good paper formation with no significant damages.

  13. Endoscopic ultrasound guided injection of iron oxide magnetic nanoparticles for liver and pancreas

    DEFF Research Database (Denmark)

    Ungureanu, Bogdan Silviu; Pirici, Daniel; Margaritescu, Claudiu

    2016-01-01

    )-guidance, both systemically and locally in the liver and pancreas in order to study new potential therapies for liver and pancreatic tumors. MATERIAL AND METHODS: Six domestic pigs were used for our study design, and divided into three groups: two were injected in the portal vein, and other four were subjected...... to local exposure of IONs in the liver and pancreas, two each. The pigs were on a 7 days follow-up and necropsy was performed with their organs harvested. A 3T MRI scan was also performed. RESULTS: All animals underwent an endoscopic ultrasound fine needle injection (EUS-FNI) procedure without any...

  14. Counter Traction Makes Endoscopic Submucosal Dissection Easier

    OpenAIRE

    Oyama, Tsuneo

    2012-01-01

    Poor counter traction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Good counter traction allows dissections to be performed more quickly and safely. Position change, which utilizes gravity, is the simplest method to create a clear field of vision. It is useful especially for esophageal and colon ESD. The second easiest method is clip with line method. Counter traction made by clip with line accomplishes the creation of a clear field of vision and suitable co...

  15. Vagal withdrawal during endoscopic retrograde cholangiopancreatography

    DEFF Research Database (Denmark)

    Christensen, M; Rasmussen, Verner; Schulze, S

    2000-01-01

    BACKGROUND: Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) are at risk of developing cardiorespiratory complications, but the mechanism is still unknown. Treatment with metoprolol 2 h before the endoscopy has been shown to decrease the incidence of myocardial ischaemia......: The existence of a defence-like reaction ('vagal withdrawal') during ERCP has been shown. Metoprolol given 2 h before the procedure did not affect the occurrence of this phenomenon. The interaction of other periendoscopic factors is still unclear and should be studied further....

  16. Automated processing of endoscopic surgical instruments.

    Science.gov (United States)

    Roth, K; Sieber, J P; Schrimm, H; Heeg, P; Buess, G

    1994-10-01

    This paper deals with the requirements for automated processing of endoscopic surgical instruments. After a brief analysis of the current problems, solutions are discussed. Test-procedures have been developed to validate the automated processing, so that the cleaning results are guaranteed and reproducable. Also a device for testing and cleaning was designed together with Netzsch Newamatic and PCI, called TC-MIC, to automate processing and reduce manual work.

  17. A Primer on Endoscopic Electronic Medical Records

    OpenAIRE

    Atreja, Ashish; Rizk, Maged; Gurland, Brooke

    2010-01-01

    Endoscopic electronic medical record systems (EEMRs) are now increasingly utilized in many endoscopy centers. Modern EEMRs not only support endoscopy report generation, but often include features such as practice management tools, image and video clip management, inventory management, e-faxes to referring physicians, and database support to measure quality and patient outcomes. There are many existing software vendors offering EEMRs, and choosing a software vendor can be time consuming and co...

  18. Properties of ligno-cellulose ficus religiosa leaf fibers

    CSIR Research Space (South Africa)

    Reddy, KO

    2010-04-01

    Full Text Available by scanning electron microscopic method. The FTIR and chemical analyses indicated lowering of hemi-cellulose content by alkali treatment of the fibers. The X-ray diffraction revealed an increase in crystallinity of the fibers on alkali treatment. The thermal...

  19. Design of Endoscopic Capsule With Multiple Cameras.

    Science.gov (United States)

    Gu, Yingke; Xie, Xiang; Li, Guolin; Sun, Tianjia; Wang, Dan; Yin, Zheng; Zhang, Pengfei; Wang, Zhihua

    2015-08-01

    In order to reduce the miss rate of the wireless capsule endoscopy, in this paper, we propose a new system of the endoscopic capsule with multiple cameras. A master-slave architecture, including an efficient bus architecture and a four level clock management architecture, is applied for the Multiple Cameras Endoscopic Capsule (MCEC). For covering more area of the gastrointestinal tract wall with low power, multiple cameras with a smart image capture strategy, including movement sensitive control and camera selection, are used in the MCEC. To reduce the data transfer bandwidth and power consumption to prolong the MCEC's working life, a low complexity image compressor with PSNR 40.7 dB and compression rate 86% is implemented. A chipset is designed and implemented for the MCEC and a six cameras endoscopic capsule prototype is implemented by using the chipset. With the smart image capture strategy, the coverage rate of the MCEC prototype can achieve 98% and its power consumption is only about 7.1 mW.

  20. Endoscopic transnasal approach for removing pituitary tumors

    Directory of Open Access Journals (Sweden)

    Mirian Cabral Moreira de Castro

    2014-05-01

    Full Text Available To describe a series of 129 consecutive patients submitted to the resection of pituitary tumors using the endoscopic transsphenoidal approach in a public medical center. Method: Retrospective analysis based on the records of patients submitted to the resection of a pituitary tumor through the endoscopic transsphenoidal approach between 2004 and 2009. Results: One hundred and twenty-nine records were analyzed. The tumor was non-secreting in 96 (74.42% and secreting in 33 patients (22.58%. Out of the secretory tumors, the most prevalent was the growth hormone producer (7.65%, followed by the prolactinoma, (6.98%. Eleven patients developed cerebral spinal fluid (CSF fistulas, and four of them developed meningitis. One patient died due to intracerebral hemorrhage in the postoperative period. Conclusion: The endoscopic transsphenoidal approach to sellar tumors proved to be safe when the majority of the tumors were non-secreting. The most frequent complication was CSF. This technique can be done even in a public hospital with financial limits, since the health professionals are integrated.

  1. Esophageal Intramural Pseudodiverticulosis: A Rare Endoscopic Finding

    Directory of Open Access Journals (Sweden)

    Luciana Lopes de Oliveira

    2013-01-01

    Full Text Available A 76-year-old woman, presenting with a 4-year history of progressive dysphagia, was submitted to endoscopic examination. The upper endoscopy revealed a proximal esophageal stricture and inflammatory mucosa associated with multiples small orifices in the esophageal wall, some of them fulfilled with white spots suggestive of fungal infection. This was a typical endoscopic finding of esophageal intramural pseudodiverticulosis, a benign and rare condition, related to chronic esophagitis and others comorbid states, such as gastroesophageal reflux disease or infectious esophagitis, diabetes mellitus, alcohol consumption, and achalasia. Dysphagia is the predominant symptom and can be accompanied by esophageal stricture in 80% to 90% of patients. The pathogenesis is unknown, and as the pseudodiverticulosis is an intramural finding, endoscopy biopsies are inconclusive. The main histological finding is dilation of the submucosal glands excretory ducts, probably obstructed by inflammatory cells. The treatment consists in management of the underlying diseases and symptoms relief. In this particular case, the patient was submitted to antifungal drugs followed by endoscopic dilation with thermoplastic bougies, with satisfactory improvement of dysphagia.

  2. Solo-Surgeon Retroauricular Approach Endoscopic Thyroidectomy.

    Science.gov (United States)

    Lee, Doh Young; Baek, Seung-Kuk; Jung, Kwang-Yoon

    2017-01-01

    This study aimed to evaluate the feasibility and efficacy of solo-surgeon retroauricular thyroidectomy. For solo-surgery, we used an Endoeye Flex Laparo-Thoraco Videoscope (Olympus America, Inc.). A Vitom Karl Storz holding system (Karl Storz GmbH & Co.) composed of several bars connected by a ball-joint system was used for fixation of endoscope. A snake retractor and a brain-spoon retractor were used on the sternocleidomastoid. Endoscopic thyroidectomy using the solo-surgeon technique was performed in 10 patients having papillary thyroid carcinoma. The mean patient age was 36.0 ± 11.1 years, and all patients were female. There were no postoperative complications such as vocal cord paralysis and hematoma. When compared with the operating times and volume of drainage of a control group of 100 patients who underwent surgery through the conventional retroauricular approach between May 2013 and December 2015, the operating times and volume of drainage were not significantly different (P = .781 and .541, respectively). Solo-surgeon retroauricular thyroidectomy is safe and feasible when performed by a surgeon competent in endoscopic thyroidectomy.

  3. Expanded Endoscopic Endonasal Resection of Retrochiasmatic Craniopharyngioma.

    Science.gov (United States)

    Davanzo, Justin R; Goyal, Neerav; Zacharia, Brad E

    2018-02-01

    This video abstract demonstrates the use of the expanded endoscopic endonasal approach for the resection of a retrochiasmatic craniopharyngioma. These tumors are notoriously difficult to treat, and many approaches have been tried to facilitate safe and effective resection. The endoscopic endonasal approach has been increasingly utilized for selected sellar/suprasellar pathology. We present the case of a 39-year-old man who was found to have a cystic, partially calcified suprasellar mass consistent with a craniopharyngioma. To facilitate robust skull base repair, a vascularized nasoseptal flap was harvested. A wide sphenoidotomy was performed and the sella and tuberculum were exposed. After the dural opening and arachnoid dissection, the stalk was identified, merging seamlessly with the tumor capsule. The lesion was then internally debulked with the use of an ultrasonic aspirator. The capsule was then dissected off of the optic chiasm, thalamus, and hypothalamus. The cavity was inspected with an angled endoscope to ensure complete resection. A multilayered reconstruction was performed using autologous fascia lata, the previously harvested nasoseptal flap, and dural sealant. Postoperatively, the patient did have expected panhypopituitarism but remained neurologically intact and had improvement in his vision. In conclusion, this video demonstrates how an expanded endonasal approach can be used to safely resect a craniopharyngioma, even when in close proximity to delicate structures such as the optic chiasm. The link to the video can be found at: https://youtu.be/tahjHmrXhc4 .

  4. Novel computer-based endoscopic camera

    Science.gov (United States)

    Rabinovitz, R.; Hai, N.; Abraham, Martin D.; Adler, Doron; Nissani, M.; Fridental, Ron; Vitsnudel, Ilia

    1995-05-01

    We have introduced a computer-based endoscopic camera which includes (a) unique real-time digital image processing to optimize image visualization by reducing over exposed glared areas and brightening dark areas, and by accentuating sharpness and fine structures, and (b) patient data documentation and management. The image processing is based on i Sight's iSP1000TM digital video processor chip and Adaptive SensitivityTM patented scheme for capturing and displaying images with wide dynamic range of light, taking into account local neighborhood image conditions and global image statistics. It provides the medical user with the ability to view images under difficult lighting conditions, without losing details `in the dark' or in completely saturated areas. The patient data documentation and management allows storage of images (approximately 1 MB per image for a full 24 bit color image) to any storage device installed into the camera, or to an external host media via network. The patient data which is included with every image described essential information on the patient and procedure. The operator can assign custom data descriptors, and can search for the stored image/data by typing any image descriptor. The camera optics has extended zoom range of f equals 20 - 45 mm allowing control of the diameter of the field which is displayed on the monitor such that the complete field of view of the endoscope can be displayed on all the area of the screen. All these features provide versatile endoscopic camera with excellent image quality and documentation capabilities.

  5. Esophageal Stricture Prevention after Endoscopic Submucosal Dissection

    Directory of Open Access Journals (Sweden)

    Deepanshu Jain

    2016-05-01

    Full Text Available Advances in diagnostic modalities and improvement in surveillance programs for Barrett esophagus has resulted in an increase in the incidence of superficial esophageal cancers (SECs. SEC, due to their limited metastatic potential, are amenable to non-invasive treatment modalities. Endoscopic ultrasound, endoscopic mucosal resection, and endoscopic submucosal dissection (ESD are some of the new modalities that gastroenterologists have used over the last decade to diagnose and treat SEC. However, esophageal stricture (ES is a very common complication and a major cause of morbidity post-ESD. In the past few years, there has been a tremendous effort to reduce the incidence of ES among patients undergoing ESD. Steroids have shown the most consistent results over time with minimal complications although the preferred mode of delivery is debatable, with both systemic and local therapy having pros and cons for specific subgroups of patients. Newer modalities such as esophageal stents, autologous cell sheet transplantation, polyglycolic acid, and tranilast have shown promising results but the depth of experience with these methods is still limited. We have summarized case reports, prospective single center studies, and randomized controlled trials describing the various methods intended to reduce the incidence of ES after ESD. Indications, techniques, outcomes, limitations, and reported complications are discussed.

  6. Treatment of nonseptic bursitis with endoscopic surgery

    Directory of Open Access Journals (Sweden)

    Azad Yıldırım

    2015-09-01

    Full Text Available Objective: The aim of this study was to show that endoscopic surgery is a simple and acceptable method for various problems associated with wounds, range of motion and that such surgery ensures an early return to work after treatment of nonresponding nonseptic bursitis. Methods: Thirty-two patients with nonseptic bursitis caused by repeated minor trauma that did not respond to medical treatment from 2008 to 2012 were included in this study. Radiographic [anteroposterior and lateral], ultrasound, macro and microscopic analyses of drainage liquid and aerobic and anaerobic cultures were obtained from the patients for the diagnosis. Results: The mean age was 40.8 years. Fifteen patients had prepatellar bursitis, 13 had olecranon bursitis and 4 had ankle bursitis. Two patients had a history of falling on their knee. The other patients had a history of repetitive stimulation .The mean follow up period was 2.6 years [range. 2-5 years] and no medical complications occurred after the endoscopic surgery; such as scarring, loss of sensation and infection. One recurrence in response to medical treatment was observed. Conclusion: Endoscopic bursectomy is a short and acceptable procedure with excellent results in terms of returning to work early and minimal wound related problems. J Clin Exp Invest 2015; 6 (3: 220-223

  7. Radiopharmaceutical scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    This invention is directed to dispersions useful in preparing radiopharmaceutical scanning agents, to technetium labelled dispersions, to methods for preparing such dispersions and to their use as scanning agents

  8. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Scan and Uptake Thyroid scan and uptake uses small amounts of radioactive materials called radiotracers, a special ... is a branch of medical imaging that uses small amounts of radioactive material to diagnose and determine ...

  9. Nuclear Heart Scan

    Science.gov (United States)

    ... Home / Nuclear Heart Scan Nuclear Heart Scan Also known as Nuclear Stress Test , ... Learn More Connect With Us Contact Us Directly Policies Privacy Policy Freedom of Information Act (FOIA) Accessibility ...

  10. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of page What will I experience during and after the procedure? Most thyroid scan and thyroid uptake ... you otherwise, you may resume your normal activities after your nuclear medicine scan. If any special instructions ...

  11. RBC nuclear scan

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003835.htm RBC nuclear scan To use the sharing features on this page, please enable JavaScript. An RBC nuclear scan uses small amounts of radioactive material to ...

  12. Endoscopic Instruments and Electrosurgical Unit for Colonoscopic Polypectomy

    OpenAIRE

    Park, Hong Jun

    2016-01-01

    Colorectal polypectomy is an effective method for prevention of colorectal cancer. Many endoscopic instruments have been used for colorectal polypectomy, such as snares, forceps, endoscopic clips, a Coagrasper, retrieval net, injector, and electrosurgery generator unit (ESU). Understanding the characteristics of endoscopic instruments and their proper use according to morphology and size of the colorectal polyp will enable endoscopists to perform effective polypectomy. I reviewed the characte...

  13. Lab-on-fiber electrophoretic trace mixture separating and detecting an optofluidic device based on a microstructured optical fiber.

    Science.gov (United States)

    Yang, Xinghua; Guo, Xiaohui; Li, Song; Kong, Depeng; Liu, Zhihai; Yang, Jun; Yuan, Libo

    2016-04-15

    We report an in-fiber integrated electrophoretic trace mixture separating and detecting an optofluidic optical fiber sensor based on a specially designed optical fiber. In this design, rapid in situ separation and simultaneous detection of mixed analytes can be realized under electro-osmotic flow in the microstructured optical fiber. To visually display the in-fiber separating and detecting process, two common fluorescent indicators are adopted as the optofluidic analytes in the optical fiber. Results show that a trace amount of the mixture (0.15 μL) can be completely separated within 3.5 min under a high voltage of 5 kV. Simultaneously, the distributed information of the separated analytes in the optical fiber can be clearly obtained by scanning along the optical fiber using a 355 nm laser. The emission from the analytes can be efficiently coupled into the inner core and guides to the remote end of the optical fiber. In addition, the thin cladding around the inner core in the optical fiber can prevent the fluorescent cross talk between the analytes in this design. Compared to previous optical fiber optofluidic devices, this device first realizes simultaneously separating treatment and the detection of the mixed samples in an optical fiber. Significantly, such an in-fiber integrated separating and detecting optofluidic device can find wide applications in various analysis fields involves mixed samples, such as biology, chemistry, and environment.

  14. Effect of fiber loading on mechanical and morphological properties of cocoa pod husk fibers reinforced thermoplastic polyurethane composites

    International Nuclear Information System (INIS)

    El-Shekeil, Y.A.; Sapuan, S.M.; Algrafi, M.W.

    2014-01-01

    Highlights: • Increase in fiber loading increased tensile strength and modulus of the composites. • Tensile strain was decreasing with increase in fiber loading. • Flexural strength and modulus increased with increase in fiber content. • Impact strength was deteriorated with increasing fiber loading. • Morphology observations shown a good adhesion between fibers and matrix. - Abstract: In this study, cocoa (Theobroma cacao) pod husk (CPH) fiber reinforced thermoplastic polyurethane (TPU) was prepared by melt compounding method using Haake Polydrive R600 internal mixer. The composites were prepared with different fiber loading: 20%, 30% and 40% (by weight), with the optimum processing parameters: 190 °C, 11 min, and 40 rpm for temperature, time and speed, respectively. Five samples were cut from the composite sheet. Mean value was taken for each composite according to ASTM standards. Effect of fiber loading on mechanical (i.e. tensile, flexural properties and impact strength) and morphological properties was studied. TPU/CPH composites showed increase in tensile strength and modulus with increase in fiber loading, while tensile strain was decreasing with increase in fiber loading. The composite also showed increase in flexural strength and modulus with increase in fiber content. Impact strength was deteriorated with increase in fiber loading. Morphology observations using Scanning Electron Microscope (SEM) showed fiber/matrix good adhesion

  15. Experience with endoscopic holmium laser in the pediatric population

    Science.gov (United States)

    Merguerian, Paul A.; Reddy, Pramod P.; Barrieras, Diego; Bagli, Darius J.; McLorie, Gordon A.; Khoury, Antoine E.

    1999-06-01

    Introduction: Due to the unavailability of suitable endoscopic instruments, pediatric patients have not benefited fully from the technological advances in the endoscopic management of the upper urinary tract. This limitation may be overcome with the Holmuim:Yttrium-Aluminum-Garnet(Ho:YAG) laser delivered via small instruments. To date, there is no published report on the use of this modality in children. Purpose: We evaluated the indications, efficacy, and complications of endourological Ho:YAG laser surgery in the treatment of pediatric urolithiasis, posterior urethral valves, ureterocele and ureteropelvic junction obstruction. Methods: The patient population included 10 children with renal, ureteral and bladder calculi, 2 children with posterior urethral valves, 2 children with obstructing ureteroceles, 2 children with ureteropelvic junction obstruction and 1 child with a urethral stricture. Access to the lesions was either antegrade via a percutaneous nephrostomy tract or retrograde via the urethra. A solid state Ho:YAG laser with maximum output of 30 watts (New Star lasers, Auburn, CA) was utilized as the energy source. Results: A total of 10 patients underwent laser lithotripsy. The means age of the patients was 9 yrs (5-13 yrs). The average surface area of the calculi as 425.2 mm2 (92-1645 mm2). 8 of the patients required one procedure to render them stone free, one patient had a staghorn calculus filling every calyx of a solitary kidney requiring multiple treatments and one other patient with a staghorn calculus required 2 treatments. There were no complications related to the laser lithotripsy. Two newborn underwent successful ablation of po sterious urethral valves. Two infants underwent incision of obstructing ureteroceles with decompression of the ureterocele on postoperative ultrasound. Two children underwent endypyelotomy for ureteropelvic junction obstruction. One was successful an done required an open procedure to correct the obstruction. One child

  16. Durability of pulp fiber-cement composites

    Science.gov (United States)

    Mohr, Benjamin J.

    Wood pulp fibers are a unique reinforcing material as they are non-hazardous, renewable, and readily available at relatively low cost compared to other commercially available fibers. Today, pulp fiber-cement composites can be found in products such as extruded non-pressure pipes and non-structural building materials, mainly thin-sheet products. Although natural fibers have been used historically to reinforce various building materials, little scientific effort has been devoted to the examination of natural fibers to reinforce engineering materials until recently. The need for this type of fundamental research has been emphasized by widespread awareness of moisture-related failures of some engineered materials; these failures have led to the filing of national- and state-level class action lawsuits against several manufacturers. Thus, if pulp fiber-cement composites are to be used for exterior structural applications, the effects of cyclical wet/dry (rain/heat) exposure on performance must be known. Pulp fiber-cement composites have been tested in flexure to examine the progression of strength and toughness degradation. Based on scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), energy dispersive spectroscopy (EDS), a three-part model describing the mechanisms of progressive degradation has been proposed: (1) initial fiber-cement/fiber interlayer debonding, (2) reprecipitation of crystalline and amorphous ettringite within the void space at the former fiber-cement interface, and (3) fiber embrittlement due to reprecipitation of calcium hydroxide filling the spaces within the fiber cell wall structure. Finally, as a means to mitigate kraft pulp fiber-cement composite degradation, the effects of partial portland cement replacement with various supplementary cementitious materials (SCMs) has been investigated for their effect on mitigating kraft pulp fiber-cement composite mechanical property degradation (i.e., strength and toughness

  17. Scanning gamma camera

    International Nuclear Information System (INIS)

    Engdahl, L.W.; Batter, J.F. Jr.; Stout, K.J.

    1977-01-01

    A scanning system for a gamma camera providing for the overlapping of adjacent scan paths is described. A collimator mask having tapered edges provides for a graduated reduction in intensity of radiation received by a detector thereof, the reduction in intensity being graduated in a direction normal to the scanning path to provide a blending of images of adjacent scan paths. 31 claims, 15 figures

  18. Endoscopic removal of a dislocated tomour prothesis from the stomach

    International Nuclear Information System (INIS)

    Rueckauer, K.; Dinkel, E.

    1985-01-01

    Endoscopic pertubation of oesophagogustric neoplasms is an established method of palliative treatment. The dislocated plastic prosthesis may be removed with difficulties from the stomach endoscopically. A simple technique for endoscopic removal of the prosthesis is described. The tube can be precisely centred within the oesophageal lumen by use of an intestinal decompression tube and additional guidance by the endoscopic retraction forceps. Thus gross damge of the exophytic tumor tissue with bleeding or perforation sequelae can be avoided. Injury to the patient does not exceed that caused by an ordinary gastroscopy. (orig.) [de

  19. Submucosal tunnel endoscopy: Peroral endoscopic myotomy and peroral endoscopic tumor resection

    Science.gov (United States)

    Eleftheriadis, Nikolas; Inoue, Haruhiro; Ikeda, Haruo; Onimaru, Manabu; Maselli, Roberta; Santi, Grace

    2016-01-01

    Peroral endoscopic myotomy (POEM) is an innovative, minimally invasive, endoscopic treatment for esophageal achalasia and other esophageal motility disorders, emerged from the natural orifice transluminal endoscopic surgery procedures, and since the first human case performed by Inoue in 2008, showed exciting results in international level, with more than 4000 cases globally up to now. POEM showed superior characteristics than the standard 100-year-old surgical or laparoscopic Heller myotomy (LHM), not only for all types of esophageal achalasia [classical (I), vigorous (II), spastic (III), Chicago Classification], but also for advanced sigmoid type achalasia (S1 and S2), failed LHM, or other esophageal motility disorders (diffuse esophageal spasm, nutcracker esophagus or Jackhammer esophagus). POEM starts with a mucosal incision, followed by submucosal tunnel creation crossing the esophagogastric junction (EGJ) and myotomy. Finally the mucosal entry is closed with endoscopic clip placement. POEM permitted relatively free choice of myotomy length and localization. Although it is technically demanding procedure, POEM can be performed safely and achieves very good control of dysphagia and chest pain. Gastroesophageal reflux is the most common troublesome side effect, and is well controllable with proton pump inhibitors. Furthermore, POEM opened the era of submucosal tunnel endoscopy, with many other applications. Based on the same principles with POEM, in combination with new technological developments, such as endoscopic suturing, peroral endoscopic tumor resection (POET), is safely and effectively applied for challenging submucosal esophageal, EGJ and gastric cardia tumors (submucosal tumors), emerged from muscularis propria. POET showed up to know promising results, however, it is restricted to specialized centers. The present article reviews the recent data of POEM and POET and discussed controversial issues that need further study and future perspectives. PMID

  20. External Dacryocystorhinostomy; Success Rate and Causes of Failure in Endoscopic and Pathologic Evaluations.

    Science.gov (United States)

    Ghasemi, Hassan; Asghari Asl, Sajedeh; Yarmohammadi, Mohammad Ebrahim; Jafari, Farhad; Izadi, Pupak

    2017-01-01

    External dacryocystorhinostomy (DCR) is the method of choice to treat nasolacrimal duct (NLD) obstruction and the other approaches are compared with it, with a failure rate of 4% to 13%. The current study aimed to assess the causes of failure in external DCR by postoperative endoscopic and pathological evaluation. The current retrospective cross sectional study followed-up113 patients with external DCR and silicone intubation for three months. Silicone tubes were removed after the third months. Failure was confirmed based on the clinical findings and irrigation test. Paranasal sinus computed tomography (CT) scanning, and endoscopic and pathological evaluations were performed in the failed cases. Totally, 113 patients underwent external DCR. The patients included 71 females and 42 males. The mean age of the patients was 55.91 years; ranged from 18 to 86. Epiphora was the most common complaint before surgery (90.3%). Clinically, epiphora continued in 17 cases (15%), of which 94.11% had at least one sinus CT abnormality and 82.35% had at least one endoscopic abnormality. The most common endoscopic findings were deviated septum (70.6%), scar tissue (52.94%), concha bullosa (46.9%), septal adhesion (47.05%), enlarged middle turbinate (41.2%), and sump syndrome (11.7%). The failure was significantly associated with the chronicity of the initial symptoms (P-value=0.00). Pathologically, there were significant relationship amongst the failure rate, scar formation, and allergic rhinitis (P-values =0.00 and <0.05, respectively). Preoperative endonasal evaluation and consultation with an otolaryngologist can improve surgical outcomes and help to have a better conscious to intranasal abnormalities before external DCR surgery.

  1. Endoscopic retrograde cholangiopancreatography, endoscopic esphinterotomy and laparoscopic cholecystectomy in a patient with choledocolitiasis and cholelitiasis

    International Nuclear Information System (INIS)

    Riveron Quevedo, Kelly; Irsula Ballaga, Vladimir; Gonzalez Ulloa, Lianne; Deborah LLorca, Armando

    2012-01-01

    The case report of a 30 year-old presumably healthy patient, who attended the Gastroenterology Department from 'Dr Juan Bruno Zayas Alfonso' Teaching General Hospital in Santiago de Cuba, and suffering from biliary cholic, ictero, choluria, nausea, vomit and loss of appetite is presented. The complementary examinations confirmed the choledocolitiasis and cholelitiasis diagnosis, reason why it was necessary to carry out a endoscopic retrograde cholangiopancreatography, endoscopic esphinterotomy and ambulatory laparoscopic cholecystectomy, in a single anesthetic injection. The postoperative clinical course was favorable and she was discharged without complications 24 hours before the intervention

  2. Endoscopic Management of an Intramural Sinus Leak After Per- Oral Endoscopic Myotomy

    Science.gov (United States)

    Al Taii, Haider; Confer, Bradley; Gabbard, Scott; Kroh, Matthew; Jang, Sunguk; Rodriguez, John; Parsi, Mansour A.; Vargo, John J.; Ponsky, Jeffrey

    2016-01-01

    Per-oral endoscopic myotomy (POEM) was developed less than a decade ago for the treatment of achalasia. Its minimally invasive approach and the favorable short-term outcome have led to rapid adoption of the technique throughout the world. As with any new technique, there will be adverse events, and it is important that effective treatments for these adverse events be discussed. We present a case of successful endoscopic management of an intramural sinus leak after a POEM procedure using tandem fully covered esophageal stents. PMID:27921057

  3. The Influence of Chemical Surface Modification of Kenaf Fiber using Hydrogen Peroxide on the Mechanical Properties of Biodegradable Kenaf Fiber/Poly(Lactic Acid Composites

    Directory of Open Access Journals (Sweden)

    Nur Inani Abdul Razak

    2014-03-01

    Full Text Available Bleaching treatment of kenaf fiber was performed in alkaline medium containing hydrogen peroxide solution maintained at pH 11 and 80 °C for 60 min. The bleached kenaf fiber was analyzed using Fourier Transform Infrared (FTIR and X-ray Diffraction (XRD analysis. The bleached kenaf fiber was then compounded with poly-(lactic acid (PLA via a melt blending method. The mechanical (tensile, flexural and impact performance of the product was tested. The fiber treatment improved the mechanical properties of PLA/bleached kenaf fiber composites. Scanning electron micrograph (SEM morphological analysis showed improvement of the interfacial adhesion between the fiber surface and polymer matrix.

  4. Characterization of an alkali-treated grass fiber by thermogravimetric and X-ray crystallographic analysis

    NARCIS (Netherlands)

    De, D.; De, Debapriya

    2008-01-01

    The thermal behavior of grass fiber was characterized by means of thermogravimetric analysis and differential scanning calorimetry analysis. The results proved that the removal of water-soluble matter improved the thermal behavior of grass fiber over that of unleached fiber, and this was further

  5. Electrospinning of aligned fibers with adjustable orientation using auxiliary electrodes

    International Nuclear Information System (INIS)

    Arras, Matthias M L; Grasl, Christian; Schima, Heinrich; Bergmeister, Helga

    2012-01-01

    A conventional electrospinning setup was upgraded by two turnable plate-like auxiliary high-voltage electrodes that allowed aligned fiber deposition in adjustable directions. Fiber morphology was analyzed by scanning electron microscopy and attenuated total reflection Fourier transform infrared spectroscopy (FTIR-ATR). The auxiliary electric field constrained the jet bending instability and the fiber deposition became controllable. At target speeds of 0.9 m s −1 90% of the fibers had aligned within 2°, whereas the angular spread was 70° without the use of auxiliary electrodes. It was even possible to orient fibers perpendicular to the rotational direction of the target. The fiber diameter became smaller and its distribution narrower, while according to the FTIR-ATR measurement the molecular orientation of the polymer was unaltered. This study comprehensively documents the feasibility of directed fiber deposition and offers an easy upgrade to existing electrospinning setups. (paper)

  6. Mechanical property evaluation of natural fiber coir composite

    International Nuclear Information System (INIS)

    Harish, S.; Michael, D. Peter; Bensely, A.; Lal, D. Mohan; Rajadurai, A.

    2009-01-01

    The fiber which serves as a reinforcement in reinforced plastics may be synthetic or natural. Past studies show that only artificial fibers such as glass, carbon etc., have been used in fiber-reinforced plastics. Although glass and other synthetic fiber-reinforced plastics possess high specific strength, their fields of application are very limited because of their inherent higher cost of production. In this connection, an investigation has been carried out to make use of coir, a natural fiber abundantly available in India. Natural fibers are not only strong and lightweight but also relatively very cheap. In the present work, coir composites are developed and their mechanical properties are evaluated. Scanning electron micrographs obtained from fractured surfaces were used for a qualitative evaluation of the interfacial properties of coir/epoxy and compared with glass fiber/epoxy. These results indicate that coir can be used as a potential reinforcing material for making low load bearing thermoplastic composites

  7. Enhancing the Dyeability of Polypropylene Fibers by Melt Blending with Polyethylene Terephthalate

    Directory of Open Access Journals (Sweden)

    Fereshteh Mirjalili

    2013-01-01

    Full Text Available Attempts were made to modify polypropylene fibers by melt blending with polyethylene terephthalate in order to enhance the dyeability of the resultant fiber. Five blends of polypropylene/polyethylene terephthalate/compatibilizer were prepared and subsequently spun into fibers. Three disperse dyes were used to dye such modified fibers at boiling and 130°C. The dyeing performance of the blend fibers, as well as the morphological, chemical, thermal, and mechanical properties, of the corresponding blends was characterized by means of spectrophotometry, polarized optical microscopy, scanning electron microscopy (SEM, FT-IR spectroscopy, differential scanning calorimetry (DSC, and tensile testing.

  8. Scanning laser microscope for imaging nanostructured superconductors

    International Nuclear Information System (INIS)

    Ishida, Takekazu; Arai, Kohei; Akita, Yukio; Miyanari, Mitsunori; Minami, Yusuke; Yotsuya, Tsutomu; Kato, Masaru; Satoh, Kazuo; Uno, Mayumi; Shimakage, Hisashi; Miki, Shigehito; Wang, Zhen

    2010-01-01

    The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB 2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor.

  9. Scanning laser microscope for imaging nanostructured superconductors

    Science.gov (United States)

    Ishida, Takekazu; Arai, Kohei; Akita, Yukio; Miyanari, Mitsunori; Minami, Yusuke; Yotsuya, Tsutomu; Kato, Masaru; Satoh, Kazuo; Uno, Mayumi; Shimakage, Hisashi; Miki, Shigehito; Wang, Zhen

    2010-10-01

    The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB 2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor.

  10. Metal adsorption process in activated carbon fiber from textile PAN fiber aim electrode production

    International Nuclear Information System (INIS)

    Rodrigues, Aline Castilho; Goncalves, Emerson Sarmento; Silva, Elen Leal da; Marcuzzo, Jossano Saldanha; Baldan, Mauricio Ribeiro; Cuna, Andres

    2016-01-01

    Full text: Carbon fibers have a variety of applications in industry and have been increasingly studied to explore their various characteristics. Studies show that the activated carbon fiber has been effective in removing small contaminants as well as activated carbon, because of its characteristic porosity. Other studies relate carbonaceous materials to the electrical conductivity devices application. This work is based on the use of an activated carbon fiber from textile polyacrylonitrile (PAN) for metallic ion adsorption from aqueous solution. Consequently, it improves the electrical characteristics and this fact show the possibility to use this material as electrode. The work was performed by adsorption process in saline solution (NO 3 Ag and ClPd) and activated carbon fiber in felt form as adsorbent. The metal adsorption on activated carbon fiber was characterized by textural analysis, x-ray diffraction (XRD), scanning electron microscopy equipped with energy dispersive x-ray (SEM-EDX), Raman spectroscopy and x-ray photoelectron spectroscopy (XPS). It was observed that activated carbon fiber showed good adsorption capacity for the metals used. At the end of the process, the activated carbon fiber samples gained about 15% by weight, related to metallic fraction incorporated into the fiber and the process of adsorption does not changed the structural, morphological and chemistry inertness of the samples. The results indicate the feasibility of this metal incorporation techniques activated carbon fiber for the production of electrodes facing the electrochemical area. (author)

  11. Mechanical and thermal properties of polymer composite based on natural fibers: Moroccan hemp fibers/polypropylene

    International Nuclear Information System (INIS)

    Elkhaoulani, A.; Arrakhiz, F.Z.; Benmoussa, K.; Bouhfid, R.; Qaiss, A.

    2013-01-01

    Highlights: ► Moroccan hemp fibers are used as reinforcement in thermoplastic matrix. ► Moroccan hemp fiber was alkali treated to remove waxes and noncellulosic component. ► Fiber–matrix adhesion was assured by the use of a SEBS-g-MA as a compatibilizer. - Abstract: Moroccan hemp is a cellulosic fiber obtained from the north of Morocco. Their use as reinforcement in thermoplastic matrix composite requires a knowledge of their morphology and structure. In this paper the Moroccan hemp fiber was alkali treated to remove waxes and noncellulosic surface components. Fiber/matrix adhesion was assured by the use of a styrene-(ethylene-butene)-styrene three-block copolymer grafted with maleic anhydride (SEBS-g-MA) as a compatibilizer. Scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), tensile and torsional tests were carried out for hemp fibers polypropylene composite and the compatibilized composite at different fiber content. Thus, the binary composite PP/hemp fibers (Alk) and ternary system with maleic anhydride indicate clearly an improved adhesion of the fiber to the matrix as results of the good interaction at the interface. A gain of 50% on the Young’s modulus of PP/hemp 25 wt.% without coupling agent and 74% on the PP/hemp 20 wt.% composite with the coupling agent were found. Tensile strength curve shows a remarkable stabilization when the coupling agent was used

  12. Metal adsorption process in activated carbon fiber from textile PAN fiber aim electrode production

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Aline Castilho; Goncalves, Emerson Sarmento, E-mail: alinerodrigues_1@msn.com [Instituto Tecnologico Aeroespacial (ITA), Sao Jose dos Campos, SP (Brazil); Silva, Elen Leal da; Marcuzzo, Jossano Saldanha; Baldan, Mauricio Ribeiro [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil); Cuna, Andres [Faculdade de Quimica, Universidad de la Republica (Uruguay)

    2016-07-01

    Full text: Carbon fibers have a variety of applications in industry and have been increasingly studied to explore their various characteristics. Studies show that the activated carbon fiber has been effective in removing small contaminants as well as activated carbon, because of its characteristic porosity. Other studies relate carbonaceous materials to the electrical conductivity devices application. This work is based on the use of an activated carbon fiber from textile polyacrylonitrile (PAN) for metallic ion adsorption from aqueous solution. Consequently, it improves the electrical characteristics and this fact show the possibility to use this material as electrode. The work was performed by adsorption process in saline solution (NO{sub 3}Ag and ClPd) and activated carbon fiber in felt form as adsorbent. The metal adsorption on activated carbon fiber was characterized by textural analysis, x-ray diffraction (XRD), scanning electron microscopy equipped with energy dispersive x-ray (SEM-EDX), Raman spectroscopy and x-ray photoelectron spectroscopy (XPS). It was observed that activated carbon fiber showed good adsorption capacity for the metals used. At the end of the process, the activated carbon fiber samples gained about 15% by weight, related to metallic fraction incorporated into the fiber and the process of adsorption does not changed the structural, morphological and chemistry inertness of the samples. The results indicate the feasibility of this metal incorporation techniques activated carbon fiber for the production of electrodes facing the electrochemical area. (author)

  13. Efficacy of functional endoscopic sinus surgery in recurrent nasal polyposis

    International Nuclear Information System (INIS)

    Aslam, S.; Ali, M.; Ahmed, A.; Asghar, A.; Aslam, S.

    2014-01-01

    To analyze the efficacy of FESS in patients with recurrent nasal polyposis in terms of relief of nasal obstruction, improvement in sense of smell and to assess recurrence of disease. Study Design: Descriptive case series. Materials and Method: All patients who underwent FESS (Functional endoscopic sinus surgery) for recurrent nasal polyposis from June 2008 to June 2010 with an average follow up of 06 month were included. Clinical symptoms including nasal obstruction and olfactory disturbance were evaluated using VAS system pre and postoperatively. Preoperatively computed tomography scan was done in all cases to assess extent of disease and surgical anatomy. Results: Following FESS 96% of total patients demonstrated statistically significant improvement in relieving nasal obstruction after 6 months follow up, however improvement in sense of smell was seen in 44% of patients. Recurrence was seen in only 3 (6%) cases at 3rd and 6th month follow up. Conclusion: Functional endoscopy sinus surgery of recurrent nasal polyposis is an effective method of surgery with significant improvement of symptom of nasal obstruction and olfaction with minimal recurrence at 6 month in our centre. Our results were compatible with results attained internationally. (author)

  14. Early endoscopic treatment of blunt traumatic pancreatic injury.

    Science.gov (United States)

    Björnsson, Bergthor; Kullman, Eric; Gasslander, Thomas; Sandström, Per

    2015-01-01

    Blunt pancreatic trauma is a rare and challenging situation. In many cases, there are other associated injuries that mandate urgent operative treatment. Morbidity and mortality rates are high and complications after acute pancreatic resections are common. The diagnosis of pancreatic injuries can be difficult and often requires multimodal approach including Computed Tomography scans, Magnetic resonance imaging and Endoscopic retrograde cholangiopancreaticography (ERCP). The objective of this paper is to review the application of endoprothesis in the settings of pancreatic injury. A review of the English literature available was conducted and the experience of our centre described. While the classical recommended treatment of Grade III pancreatic injury (transection of the gland and the pancreatic duct in the body/tail) is surgical resection this approach carries high morbidity. ERCP was first reported as a diagnostic tool in the settings of pancreatic injury but has in recent years been used increasingly as a treatment option with promising results. This article reviews the literature on ERCP as treatment option for pancreatic injury and adds further to the limited number of cases reported that have been treated early after the trauma.

  15. MR imaging of colorectal carcinomas using an MR endoscopic coil

    International Nuclear Information System (INIS)

    Murano, Akihiko; Kido, Choichiro; Sasaki, Fumio; Nakamura, Tsuneya; Kobayashi, Semi; Katoh, Tomoyuki; Hirai, Takashi

    1994-01-01

    Diagnosis of the depth of wall invasion by rectal carcinoma using MR endoscopy was performed in ten resected specimens, including five rectal carcinomas, three colon carcinomas, two normal gastric wall. In addition, the gastric wall of a pig was examined. MR imaging was done with a 1.5-T Signa Advantage (GE Medical System) system, with the surface coil of the MR endoscope acting as the receiver coil. Five layers could be distinguished in the bowel wall: mucosa, submucosa and muscularis propria divided into circular muscle, longitudinal muscle and intervening connective tissue. Tumors had almost the same signal intensity as muscle. The MR images of colon carcinomas, rectal carcinomas, and extrinsically metastatic involvement of the sigmoid colon by rectal carcinoma all correlated well with the pathological findings. The normal structure of the gastric wall was similar to that of the colon. 3D-fast Spoiled Grass (SPGR) sequence has a fairly short scanning time. Thus, the possibility of precise clinical diagnosis by this method was suggested. (author)

  16. Effect of fiber orientation on tensile and impact properties of Zalacca Midrib fiber-HDPE composites by compression molding

    Science.gov (United States)

    Lasikun, Ariawan, Dody; Surojo, Eko; Triyono, Joko

    2018-02-01

    The research aims to investigate the fiber orientation effect on the tensile and impact properties of zalacca midrib fiber /HDPE composites. The composites were produced by compression molding with pressing temperature at 150°C, pressing pressure at 50 bar, and holding time of 25 minutes. The fiber orientations applied in composites were 0°, 15°, 30°, 45°, 60°, 75°, and 90°, at 10% fiber volume fraction. The samples were evaluated by using: Tensile test and Izod impact test according to ASTM D638 and ASTM D5941, respectively. The result of experiments indicate that the orientation of zalacca midrib fiber influences the characteristics of HDPE composite-zalacca midrib fiber. The composite mechanical strength decline with the increase of orientation fibers from 0° to 90°. The composite failure mode of composites are observed by Scanning Electron Microscope (SEM).

  17. Advanced stabilization of PAN fibers for fabrication of carbon fibers by e-beam irradiation

    International Nuclear Information System (INIS)

    Jeun, Joon Pyo; Kim, Du Young; Shin, Hye Kyoung; Kang, Phil Hyun; Park, Jung Ki

    2012-01-01

    In recent years, the carbon fiber industry has been growing rapidly to meet the demand from efferent industries such as aerospace, military, turbine blades, light weight cylinders and pressure vessels. Generally, carbon fibers are manufactured by a controlled pyrolysis of stabilized precursor fiber such as polyacrylonitrile (PAN). In the stabilization step, the linear PAN molecules are first converted to cyclic structure. However, cyclization is a very complicated process and there are still differences of opinion on the reaction mechanisms. Photo-induced crosslinking and stabilization of PAN via ion beam, X-ray, gamma ray and UV irradiation has been reported in the literature. However, the process required a long stabilization time. In this work, a new and highly effective method of pretreatment PAN precursor fiber was described. The effect of the e-beam on the stabilization process of the fibers was investigated using differential scanning calorimeter (DSC) and X-ray diffraction (XRD) measurement

  18. Transforming Pristine Carbon Fiber Tows into High Performance Solid-State Fiber Supercapacitors.

    Science.gov (United States)

    Yu, Dingshan; Zhai, Shengli; Jiang, Wenchao; Goh, Kunli; Wei, Li; Chen, Xudong; Jiang, Rongrong; Chen, Yuan

    2015-09-02

    A facile activation strategy can transform pristine carbon fiber tows into high-performance fiber electrodes with a specific capacitance of 14.2 F cm(-3) . The knottable fiber supercapacitor shows an energy density of 0.35 mW h cm(-3) , an ultrahigh power density of 3000 mW cm(-3) , and a remarkable capacitance retention of 68%, when the scan rate increases from 10 to 1000 mV s(-1) . © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Endoscopic ultrasound-guided hepaticogastrostomy for advanced cholangiocarcinoma after failed stenting by endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Sukij Panpimanmas

    2013-10-01

    Conclusion: Endoscopic-ultrasound-guided hepaticogastrostomy is safe and can be a good palliative option for advanced malignant biliary obstruction because it drains internally and is remote from the tumor site, promoting a long patency period of prosthesis and better quality of life.

  20. Endoscopic Radiofrequency Ablation-Assisted Resection of Juvenile Nasopharyngeal Angiofibroma: Comparison with Traditional Endoscopic Technique.

    Science.gov (United States)

    McLaughlin, Eamon J; Cunningham, Michael J; Kazahaya, Ken; Hsing, Julianna; Kawai, Kosuke; Adil, Eelam A

    2016-06-01

    To evaluate the feasibility of radiofrequency surgical instrumentation for endoscopic resection of juvenile nasopharyngeal angiofibroma (JNA) and to test the hypothesis that endoscopic radiofrequency ablation-assisted (RFA) resection will have superior intraoperative and/or postoperative outcomes as compared with traditional endoscopic (TE) resection techniques. Case series with chart review. Two tertiary care pediatric hospitals. Twenty-nine pediatric patients who underwent endoscopic transnasal resection of JNA from January 2000 to December 2014. Twenty-nine patients underwent RFA (n = 13) or TE (n = 16) JNA resection over the 15-year study period. Mean patient age was not statistically different between the 2 groups (P = .41); neither was their University of Pittsburgh Medical Center classification stage (P = .79). All patients underwent preoperative embolization. Mean operative times were not statistically different (P = .29). Mean intraoperative blood loss and the need for a transfusion were also not statistically different (P = .27 and .47, respectively). Length of hospital stay was not statistically different (P = .46). Recurrence rates did not differ between groups (P = .99) over a mean follow-up period of 2.3 years. There were no significant differences between RFA and TE resection in intraoperative or postoperative outcome parameters. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  1. Significance of endoscopic screening and endoscopic resection for esophageal cancer in patients with hypopharyngeal cancer

    International Nuclear Information System (INIS)

    Morimoto, Masahiro; Nishiyama, Kinji; Nakamura, Satoaki

    2010-01-01

    The efficacy of endoscopic screening for esophageal cancer in patients with hypopharyngeal cancer remains controversial and its impact on prognosis has not been adequately discussed. We studied the use of endoscopic screening to detect esophageal cancer in hypopharyngeal cancer patients by analyzing the incidence, stage and prognosis. We included 64 patients with hypopharyngeal cancer who received radical radiotherapy at our institute. Chromoendoscopic esophageal examinations with Lugol dye solution were routinely performed at and after treatment for hypopharyngeal cancer. Twenty-eight esophageal cancers were detected in 28 (41%) patients (18 synchronous and 10 metachronous cancers). Of the 28 cancers, 23 were stage 0 or I cancer and 15 of these were treated with endoscopic resection. Local control was achieved in all of these 23 stage 0 or I cancers. The 5-year overall survival rates with esophageal cancer were 83% in stage 0, 47% in stage I and 0% in stage IIA-IVB. This study showed a strikingly high incidence of esophageal cancer in hypopharyngeal cancer patients. We suppose that the combination of early detection by chromoendoscopic examination and endoscopic resection for associated esophageal cancer in hypopharyngeal cancer patients improve prognosis and maintain quality of life. (author)

  2. Interactions between the glass fiber coating and oxidized carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Ku-Herrera, J.J., E-mail: jesuskuh@live.com.mx [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Avilés, F., E-mail: faviles@cicy.mx [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Nistal, A. [Instituto de Cerámica y Vidrio (ICV-CSIC), Kelsen 5, 28049 Madrid (Spain); Cauich-Rodríguez, J.V. [Centro de Investigación Científica de Yucatán A.C., Unidad de Materiales, Calle 43 No.130, Col. Chuburná de Hidalgo. C.P., 97200 Mérida, Yucatán (Mexico); Rubio, F.; Rubio, J. [Instituto de Cerámica y Vidrio (ICV-CSIC), Kelsen 5, 28049 Madrid (Spain); Bartolo-Pérez, P. [Departamento de Física Aplicada, Cinvestav, Unidad Mérida, C.P., 97310 Mérida, Yucatán (Mexico)

    2015-03-01

    Graphical abstract: - Highlights: • Oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto E-glass fibers. • The role of the fiber coating on the deposition of MWCNTs on the fibers is studied. • A rather homogeneous deposition of MWCNTs is achieved if the coating is maintained. • Multiple oxygen-containing groups were found in the analysis of the fiber coating. • Evidence of chemical interaction between MWCNTs and the fiber coating was found. - Abstract: Chemically oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto commercial E-glass fibers using a dipping procedure assisted by ultrasonic dispersion. In order to investigate the role of the fiber coating (known as “sizing”), MWCNTs were deposited on the surface of as-received E-glass fibers preserving the proprietary coating as well as onto glass fibers which had the coating deliberately removed. Scanning electron microscopy and Raman spectroscopy were used to assess the distribution of MWCNTs onto the fibers. A rather homogeneous coverage with high density of MWCNTs onto the glass fibers is achieved when the fiber coating is maintained. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analyses of the chemical composition of the glass fiber coating suggest that such coating is a complex mixture with multiple oxygen-containing functional groups such as hydroxyl, carbonyl and epoxy. FTIR and XPS of MWCNTs over the glass fibers and of a mixture of MWCNTs and fiber coating provided evidence that the hydroxyl and carboxyl groups of the oxidized MWCNTs react with the oxygen-containing functional groups of the glass fiber coating, forming hydrogen bonding and through epoxy ring opening. Hydrogen bonding and ester formation between the functional groups of the MWCNTs and the silane contained in the coating are also possible.

  3. Interactions between the glass fiber coating and oxidized carbon nanotubes

    International Nuclear Information System (INIS)

    Ku-Herrera, J.J.; Avilés, F.; Nistal, A.; Cauich-Rodríguez, J.V.; Rubio, F.; Rubio, J.; Bartolo-Pérez, P.

    2015-01-01

    Graphical abstract: - Highlights: • Oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto E-glass fibers. • The role of the fiber coating on the deposition of MWCNTs on the fibers is studied. • A rather homogeneous deposition of MWCNTs is achieved if the coating is maintained. • Multiple oxygen-containing groups were found in the analysis of the fiber coating. • Evidence of chemical interaction between MWCNTs and the fiber coating was found. - Abstract: Chemically oxidized multiwall carbon nanotubes (MWCNTs) were deposited onto commercial E-glass fibers using a dipping procedure assisted by ultrasonic dispersion. In order to investigate the role of the fiber coating (known as “sizing”), MWCNTs were deposited on the surface of as-received E-glass fibers preserving the proprietary coating as well as onto glass fibers which had the coating deliberately removed. Scanning electron microscopy and Raman spectroscopy were used to assess the distribution of MWCNTs onto the fibers. A rather homogeneous coverage with high density of MWCNTs onto the glass fibers is achieved when the fiber coating is maintained. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analyses of the chemical composition of the glass fiber coating suggest that such coating is a complex mixture with multiple oxygen-containing functional groups such as hydroxyl, carbonyl and epoxy. FTIR and XPS of MWCNTs over the glass fibers and of a mixture of MWCNTs and fiber coating provided evidence that the hydroxyl and carboxyl groups of the oxidized MWCNTs react with the oxygen-containing functional groups of the glass fiber coating, forming hydrogen bonding and through epoxy ring opening. Hydrogen bonding and ester formation between the functional groups of the MWCNTs and the silane contained in the coating are also possible

  4. Endoscopic Lung Volume Reduction : An Expert Panel Recommendation - Update 2017

    NARCIS (Netherlands)

    Herth, Felix J. F.; Slebos, Dirk-Jan; Criner, Gerard J.; Shah, Pallav L.

    2017-01-01

    Interest in endoscopic lung volume reduction (ELVR) technologies for emphysema is consistently growing. In the last couple of months, several endoscopic options (e.g., endo-or intrabronchial valves, coil implants, and thermal vapor ablation) that have been evaluated in randomized controlled trials

  5. Endoscopic and histologic healing of Crohn's (ileo-) colitis with azathioprine

    NARCIS (Netherlands)

    D'Haens, G.; Geboes, K.; Rutgeerts, P.

    1999-01-01

    The correlation between disease activity and endoscopic findings in Crohn's disease is poor. Corticosteroids induce symptom relief without consistent improvement of endoscopic lesions. Our aim was to examine the effect of azathioprine therapy on healing of inflammatory lesions in patients with

  6. Is endoscopic nodular gastritis associated with premalignant lesions?

    Science.gov (United States)

    Niknam, R; Manafi, A; Maghbool, M; Kouhpayeh, A; Mahmoudi, L

    2015-06-01

    Nodularity on the gastric mucosa is occasionally seen in general practice. There is no consensus about the association of nodular gastritis and histological premalignant lesions. This study is designed to investigate the prevalence of histological premalignant lesions in dyspeptic patients with endoscopic nodular gastritis. Consecutive patients with endoscopic nodular gastritis were compared with an age- and sex-matched control group. Endoscopic nodular gastritis was defined as a miliary nodular appearance of the gastric mucosa on endoscopy. Biopsy samples of stomach tissue were examined for the presence of atrophic gastritis, intestinal metaplasia, and dysplasia. The presence of Helicobacter pylori infection was determined by histology. From 5366 evaluated patients, a total of 273 patients with endoscopic nodular gastritis and 1103 participants as control group were enrolled. H. pylori infection was detected in 87.5% of the patients with endoscopic nodular gastritis, whereas 73.8% of the control group were positive for H. pylori (p gastritis were significantly higher than in the control group. Prevalence of atrophic gastritis and complete intestinal metaplasia were also more frequent in patients with endoscopic nodular gastritis than in the control group. Dysplasia, incomplete intestinal metaplasia and H. pylori infection are significantly more frequent in patients with endoscopic nodular gastritis. Although further studies are needed before a clear conclusion can be reached, we suggest that endoscopic nodular gastritis might serve as a premalignant lesion and could be biopsied in all patients for the possibility of histological premalignancy, in addition to H. pylori infection.

  7. Endoscopic versus surgical drainage treatment of calcific chronic pancreatitis.

    Science.gov (United States)

    Jiang, Li; Ning, Deng; Cheng, Qi; Chen, Xiao-Ping

    2018-04-21

    Endoscopic therapy and surgery are both conventional treatments to remove pancreatic duct stones that developed during the natural course of chronic pancreatitis. However, few studies comparing the effect and safety between surgery drainage and endoscopic drainage (plus Extracorporeal Shock Wave Lithotripsy, ESWL).The aim of this study was to compare the benefits between endoscopic and surgical drainage of the pancreatic duct for patients with calcified chronic pancreatitis. A total of 86 patients were classified into endoscopic/ESWL (n = 40) or surgical (n = 46) treatment groups. The medical records of these patients were retrospectively analyzed. Pain recurrence and hospital stays were similar between the endoscopic/ESWL treatment and surgery group. However, endoscopic/ESWL treatment yielded significantly lower medical expense and less complications compared with the surgical treatment. In selective patients, endoscopic/ESWL treatment could achieve comparable efficacy to the surgical treatment. With lower medical expense and less complications, endoscopic/ESWL treatment would be much preferred to be the initial treatment of choice for patients with calcified chronic pancreatitis. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  8. Endoscopic lesions in Crohn's disease early after ileocecal resection

    NARCIS (Netherlands)

    Tytgat, G. N.; Mulder, C. J.; Brummelkamp, W. H.

    1988-01-01

    Fifty patients with Crohn's disease were studied endoscopically 6 weeks to 6 months (median 9 weeks) after ileocecal or ileocolonic resection for evidence of non-resected abnormality. Only 8 of the 50 patients were endoscopically free of abnormalities. Microscopic examination of the surgical

  9. The clinical and endoscopic spectrum of the watermelon stomach

    NARCIS (Netherlands)

    Gostout, C. J.; Viggiano, T. R.; Ahlquist, D. A.; Wang, K. K.; Larson, M. V.; Balm, R.

    1992-01-01

    The watermelon stomach is an uncommon but treatable cause of chronic gastrointestinal bleeding. We report our experience with the clinical and endoscopic features of 45 consecutive patients treated by endoscopic Nd:YAG laser coagulation. The prototypic patient was a woman (71%) with an average age

  10. Responsiveness of Endoscopic Indices of Disease Activity for Crohn's Disease

    NARCIS (Netherlands)

    Khanna, Reena; Zou, Guangyong; Stitt, Larry; Feagan, Brian G.; Sandborn, William J.; Rutgeerts, Paul; McDonald, John W. D.; Dubcenco, Elena; Fogel, Ronald; Panaccione, Remo; Jairath, Vipul; Nelson, Sigrid; Shackelton, Lisa M.; Huang, Bidan; Zhou, Qian; Robinson, Anne M.; Levesque, Barrett G.; D'Haens, Geert

    2017-01-01

    The Crohn's Disease Endoscopic Index of Severity (CDEIS) and the Simple Endoscopic Score for Crohn's Disease (SES-CD) are commonly used to assess Crohn's disease (CD) activity; however neither instrument is fully validated. We evaluated the responsiveness to change of the SES-CD and CDEIS using data

  11. Evaluation of flexible endoscope steering using haptic guidance

    NARCIS (Netherlands)

    Reilink, Rob; Stramigioli, Stefano; Kappers, Astrid M L; Misra, Sarthak

    Background: Steering the tip of a flexible endoscope relies on the physician's dexterity and experience. For complex flexible endoscopes, conventional controls may be inadequate. Methods: A steering method based on a multi-degree-of-freedom haptic device is presented. Haptic cues are generated based

  12. Endoscopic Camera Control by Head Movements for Thoracic Surgery

    NARCIS (Netherlands)

    Reilink, Rob; de Bruin, Gart; Franken, M.C.J.; Mariani, Massimo A.; Misra, Sarthak; Stramigioli, Stefano

    2010-01-01

    In current video-assisted thoracic surgery, the endoscopic camera is operated by an assistant of the surgeon, which has several disadvantages. This paper describes a system which enables the surgeon to control the endoscopic camera without the help of an assistant. The system is controlled using

  13. Evaluation of flexible endoscope steering using haptic guidance

    NARCIS (Netherlands)

    Reilink, Rob; Stramigioli, Stefano; Kappers, Astrid M.L.; Misra, Sarthak

    2011-01-01

    Background - Steering the tip of a flexible endoscope relies on the physician’s dexterity and experience. For complex flexible endoscopes, conventional controls may be inadequate. Methods - A steering method based on a multi-degree-of-freedom haptic device is presented. Haptic cues are generated

  14. In-line optical fiber metallic mirror reflector for monolithic common path optical coherence tomography probes.

    Science.gov (United States)

    Singh, Kanwarpal; Reddy, Rohith; Sharma, Gargi; Verma, Yogesh; Gardecki, Joseph A; Tearney, Guillermo

    2018-03-01

    Endoscopic optical coherence tomography probes suffer from various artifacts due to dispersion imbalance and polarization mismatch between reference and sample arm light. Such artifacts can be minimized using a common path approach. In this work, we demonstrate a miniaturized common path probe for optical coherence tomography using an inline fiber mirror. A common path optical fiber probe suitable for performing high-resolution endoscopic optical coherence tomography imaging was developed. To achieve common path functionality, an inline fiber mirror was fabricated using a thin gold layer. A commercially available swept source engine was used to test the designed probe in a cadaver human coronary artery ex vivo. We achieved a sensitivity of 104 dB for this probe using a swept source optical coherence tomography system. To test the probe, images of a cadaver human coronary artery were obtained, demonstrating the quality that is comparable to those obtained by OCT systems with separate reference arms. Additionally, we demonstrate recovery of ranging depth by use of a Michelson interferometer in the detection path. We developed a miniaturized monolithic inline fiber mirror-based common path probe for optical coherence tomography. Owing to its simplicity, our design will be helpful in endoscopic applications that require high-resolution probes in a compact form factor while reducing system complexity. Lasers Surg. Med. 50:230-235, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Fibered F-Algebra

    OpenAIRE

    Kleyn, Aleks

    2007-01-01

    The concept of F-algebra and its representation can be extended to an arbitrary bundle. We define operations of fibered F-algebra in fiber. The paper presents the representation theory of of fibered F-algebra as well as a comparison of representation of F-algebra and of representation of fibered F-algebra.

  16. Photonic crystal fibers

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper; Hansen, K P; Nielsen, M D

    2003-01-01

    Photonic crystal fibers having a complex microstructure in the transverse plane constitute a new and promising class of optical fibers. Such fibers can either guide light through total internal reflection or the photonic bandgap effect, In this paper, we review the different types and applications...... of photonic crystal fibers with particular emphasis on recent advances in the field....

  17. Photonic crystal fibers -

    DEFF Research Database (Denmark)

    Libori, Stig E. Barkou

    2002-01-01

    . Such micro-structured fibers are the ones most often trated in literature concerning micro-structured fibers. These micro-structured fibers offer a whole range of novel wave guiding characteristics, including the possibility of fibers that guide only one mode irrespective of the frequency of light...

  18. [Pull percutaneous endoscopic gastrostomy: personal experience].

    Science.gov (United States)

    Geraci, G; Sciumè, C; Pisello, F; Li Volsi, F; Facella, T; Tinaglia, D; Modica, G

    2007-04-01

    To review the indications, complications, and outcomes of percutaneous endoscopic gastrostomy (PEG), that are placed routinely in patients unable to obtain adequate nutrition from oral feeding for swallowing disorders (neurological diseases, head and neck cancer, oesophageal cancer, psychological disorders). Retrospective review of patients referred for PEG placement from 2003 to 2005. Endoscopic Surgery in Section of General and Thoracic Surgery, Faculty of Medicine and Surgery, Palermo, Italy. A total of 50 patients, 11 women and 39 men, referred our Section for PEG placement. Indications for PEG placement included various neurologic impairment (82%), oesophageal non-operable cancer (6%), cardia non-operable cancer (4%), cerebrovascular accident (2%), anorexia (2%), pharyngeal esophageal obstruction (2%), head and neck cancer (2%). All patients received preoperative antibiotics as short-term profilaxis. 51 PEGs were positioned in 50 patients. No major complications were registered; 45 patients (90%) were alive at 1 year follow-up and no mortality procedure-related was registered. Percutaneous endoscopic gastrotomy removal had been performed on 2 patients as end-point of treatment, and 43 patients continued to have PEGs in use at 2006. Outpatients PEG placement using conscious sedation is a safe and effective method for providing enteral nutrition. This technique constitutes the gold standard treatment for enteral nutrition in patients with neurologic impairment or as prophylactic in patients affected by head and neck cancer who needs demolitive surgery. Patients should be carefully assessed, and discussion with the patient and their families should be held to determine that the patient is an appropriate candidate. The Authors feel prophylactic antibiotics lessened the incidence of cutaneous perigastrostomy infection.

  19. Endoscopic optical coherence tomography with a modified microelectromechanical systems mirror for detection of bladder cancers

    Science.gov (United States)

    Xie, Tuqiang; Xie, Huikai; Fedder, Gary K.; Pan, Yingtian

    2003-11-01

    Experimental results of a modified micromachined microelectromechanical systems (MEMS) mirror for substantial enhancement of the transverse laser scanning performance of endoscopic optical coherence tomography (EOCT) are presented. Image distortion due to buckling of MEMS mirror in our previous designs was analyzed and found to be attributed to excessive internal stress of the transverse bimorph meshes. The modified MEMS mirror completely eliminates bimorph stress and the resultant buckling effect, which increases the wobbling-free angular optical actuation to greater than 37°, exceeding the transverse laser scanning requirements for EOCT and confocal endoscopy. The new optical coherence tomography (OCT) endoscope allows for two-dimensional cross-sectional imaging that covers an area of 4.2 mm × 2.8 mm (limited by scope size) and at roughly 5 frames/s instead of the previous area size of 2.9 mm × 2.8 mm and is highly suitable for noninvasive and high-resolution imaging diagnosis of epithelial lesions in vivo. EOCT images of normal rat bladders and rat bladder cancers are compared with the same cross sections acquired with conventional bench-top OCT. The results clearly demonstrate the potential of EOCT for in vivo imaging diagnosis and precise guidance for excisional biopsy of early bladder cancers.

  20. Endoscopic treatment of Morel-Lavallee lesion.

    Science.gov (United States)

    Kim, Sunghoon

    2016-05-01

    Morel-Lavallee lesion is a closed degloving soft tissue injury in which subcutaneous tissue is torn from the underlying muscular fascia. The tear leads to venolymphatic leak, and concomitant adipose tissue necrosis from the force of the trauma causes swelling and possible infection at the site of injury. The traditional treatment for the lesion is surgical drainage and debridement. In this report, an endoscopic method is described, which achieves the goal of an open surgical debridement but minimizes surgical morbidity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. A primer on endoscopic electronic medical records.

    Science.gov (United States)

    Atreja, Ashish; Rizk, Maged; Gurland, Brooke

    2010-02-01

    Endoscopic electronic medical record systems (EEMRs) are now increasingly utilized in many endoscopy centers. Modern EEMRs not only support endoscopy report generation, but often include features such as practice management tools, image and video clip management, inventory management, e-faxes to referring physicians, and database support to measure quality and patient outcomes. There are many existing software vendors offering EEMRs, and choosing a software vendor can be time consuming and confusing. The goal of this article is inform the readers about current functionalities available in modern EEMR and provide them with a framework necessary to find an EEMR that is best fit for their practice.

  2. Image acquisition in laparoscopic and endoscopic surgery

    Science.gov (United States)

    Gill, Brijesh S.; Georgeson, Keith E.; Hardin, William D., Jr.

    1995-04-01

    Laparoscopic and endoscopic surgery rely uniquely on high quality display of acquired images, but a multitude of problems plague the researcher who attempts to reproduce such images for educational purposes. Some of these are intrinsic limitations of current laparoscopic/endoscopic visualization systems, while others are artifacts solely of the process used to acquire and reproduce such images. Whatever the genesis of these problems, a glance at current literature will reveal the extent to which endoscopy suffers from an inability to reproduce what the surgeon sees during a procedure. The major intrinsic limitation to the acquisition of high-quality still images from laparoscopic procedures lies in the inability to couple directly a camera to the laparoscope. While many systems have this capability, this is useful mostly for otolaryngologists, who do not maintain a sterile field around their scopes. For procedures in which a sterile field must be maintained, one trial method has been to use a beam splitter to send light both to the still camera and the digital video camera. This is no solution, however, since this results in low quality still images as well as a degradation of the image that the surgeon must use to operate, something no surgeon tolerates lightly. Researchers thus must currently rely on other methods for producing images from a laparoscopic procedure. Most manufacturers provide an optional slide or print maker that provides a hardcopy output from the processed composite video signal. The results achieved from such devices are marginal, to say the least. This leaves only one avenue for possible image production, the videotape record of an endoscopic or laparoscopic operation. Video frame grabbing is at least a problem to which industry has applied considerable time and effort to solving. Our own experience with computerized enhancement of videotape frames has been very promising. Computer enhancement allows the researcher to correct several of the

  3. Fiber optic connector

    Science.gov (United States)

    Rajic, Slobodan; Muhs, Jeffrey D.

    1996-01-01

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled.

  4. Endoscopic electrosurgical papillotomy and manometry in biliary tract disease.

    Science.gov (United States)

    Geenen, J E; Hogan, W J; Shaffer, R D; Stewart, E T; Dodds, W J; Arndorfer, R C

    1977-05-09

    Endoscopic papillotomy was performed in 13 patients after cholecystectomy for retained or recurrent common bile duct calculi (11 patients) and a clinical picture suggesting papillary stenosis (two patients). Following endoscopic papillotomy, ten of the 11 patients spontaneously passed common bile duct (CBD) stones verified on repeated endoscopic retrograde cholangiopancreatography (ERCP) study. One patient failed to pass a large CBD calculus; one patient experienced cholangitis three months after in inadequate papillotomy and required operative intervention. Endoscopic papillotomy substantially decreased the pressure gradient existing between the CBD and the duodenum in all five patients studied with ERCP manometry. Endoscopic papillotomy is a relatively safe and effective procedure for postcholecystectomy patients with retained or recurrent CBD stones. The majority of CBD stones will pass spontaneously if the papillotomy is adequate.

  5. Ultrasound-assisted endoscopic partial plantar fascia release.

    Science.gov (United States)

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure.

  6. Direct cost comparison of totally endoscopic versus open ear surgery.

    Science.gov (United States)

    Patel, N; Mohammadi, A; Jufas, N

    2018-02-01

    Totally endoscopic ear surgery is a relatively new method for managing chronic ear disease. This study aimed to test the null hypothesis that open and endoscopic approaches have similar direct costs for the management of attic cholesteatoma, from an Australian private hospital setting. A retrospective direct cost comparison of totally endoscopic ear surgery and traditional canal wall up mastoidectomy for the management of attic cholesteatoma in a private tertiary setting was undertaken. Indirect and future costs were excluded. A direct cost comparison of anaesthetic setup and resources, operative setup and resources, and surgical time was performed between the two techniques. Totally endoscopic ear surgery has a mean direct cost reduction of AUD$2978.89 per operation from the hospital perspective, when compared to canal wall up mastoidectomy. Totally endoscopic ear surgery is more cost-effective, from an Australian private hospital perspective, than canal wall up mastoidectomy for attic cholesteatoma.

  7. Surface structure and adsorption properties of ultrafine porous carbon fibers

    International Nuclear Information System (INIS)

    Song Xiaofeng; Wang Ce; Zhang Dejiang

    2009-01-01

    Ultrafine porous carbon fibers (UPCFs) were successfully synthesized by chemical activation of electrospun polyacrylonitrile fibers. In the current approach, potassium hydroxide was adopted as activation reagent. UPCFs were systematically evaluated by scanning electron microscope and nitrogen adsorption. The mass ratio of potassium hydroxide to preoxidized fibers, activation temperature and activation time are crucial for producing high quality UPCFs. The relationships between porous structure and process parameters are explored. UPCFs were applied as adsorbent for nitrogen monoxide to be compared with commercial porous carbon fibers.

  8. Lung PET scan

    Science.gov (United States)

    ... Chest PET scan; Lung positron emission tomography; PET - chest; PET - lung; PET - tumor imaging; ... Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging . 6th ed. Philadelphia, ...

  9. Scanning of bone metastases

    International Nuclear Information System (INIS)

    Robillard, J.

    1977-01-01

    The Centers against cancer of Caen, Angers, Montpellier, Strasbourg and 'the Curie Foundation' have confronted their experience in detection of bone metastases by total body scanning. From the investigation by this procedure, of 1,467 patients with cancer, it results: the confrontation between radio and scanning shows a rate of false positive and false negative identical to the literature ones; the countage scanning allows to reduce the number of false positive; scanning allows to direct bone biopsy and to improve efficiency of histological examination [fr

  10. Use of industrial wireless endoscope in intrauterine artificial insemination in sheep

    Directory of Open Access Journals (Sweden)

    Gutierrez EF

    2017-08-01

    Full Text Available The aim of this study was to evaluate the use of an industrial wireless endoscope on the pregnancy rate of Hampshire Down sheep with intrauterine insemination. The work was carried out in a farm of the community Sullkataca Baja of the municipality of Laja, department of La Paz, Bolivia. The conditioning of an endoscopy equipment (Wifi Endoscope®, Teslong which had a portable and multifunctional Wi-Fi camera with fiber optic 8.5mm diameter, LED light and real-time video transmission at 720P. Also, 2 metal trocars (used in cattle were adapted to facilitate the entrance of the endoscopy and the insemination pipette. The estrus synchronization was performed in 10 nulliparas and 10 multiparas by means of intravaginal sponges with 60 mg of medroxyprogesterone acetate (Progespon®, Lab. Syntex Argentina for 14 days. A dose of 500 IU of eCG (Sergon®, Lab. Bioveta Czech Republic is applied to the removal of the sponges. At 52.31 ± 0.31 hours post removal of the sponges, artificial insemination fixed time (FTAI was performed with frozen semen in straws of 0.25cc with 40 million spermatozoa. During insemination, the values of 80% and 100% of uterine horn turgor were determined for the group of pluriparas and nulliparas respectively. The pregnancy diagnosis was performed at 50 days post insemination using ultrasound transrectal (EMP 820 vet plus®, Emperor China. Gestation rates were 60% for lambs and 70% for ewes (P≥0.05. In conclusion, the industrial wireless endoscope is an economical, versatile equipment and can be used efficiently to perform intrauterine IATF with frozen semen in sheep.

  11. A technical review of flexible endoscopic multitasking platforms.

    Science.gov (United States)

    Yeung, Baldwin Po Man; Gourlay, Terence

    2012-01-01

    Further development of advanced therapeutic endoscopic techniques and natural orifice translumenal endoscopic surgery (NOTES) requires a powerful flexible endoscopic multitasking platform. Medline search was performed to identify literature relating to flexible endoscopic multitasking platform from year 2004-2011 using keywords: Flexible endoscopic multitasking platform, NOTES, Instrumentation, Endoscopic robotic surgery, and specific names of various endoscopic multitasking platforms. Key articles from articles references were reviewed. Flexible multitasking platforms can be classified as either mechanical or robotic. Purely mechanical systems include the dual channel endoscope (DCE) (Olympus), R-Scope (Olympus), the EndoSamurai (Olympus), the ANUBIScope (Karl-Storz), Incisionless Operating Platform (IOP) (USGI), and DDES system (Boston Scientific). Robotic systems include the MASTER system (Nanyang University, Singapore) and the Viacath (Hansen Medical). The DCE, the R-Scope, the EndoSamurai and the ANUBIScope have integrated visual function and instrument manipulation function. The IOP and DDES systems rely on the conventional flexible endoscope for visualization, and instrument manipulation is integrated through the use of a flexible, often lockable, multichannel access device. The advantage of the access device concept is that it allows optics and instrument dissociation. Due to the anatomical constrains of the pharynx, systems are designed to have a diameter of less than 20 mm. All systems are controlled by traction cable system actuated either by hand or by robotic machinery. In a flexible system, this method of actuation inevitably leads to significant hysteresis. This problem will be accentuated with a long endoscope such as that required in performing colonic procedures. Systems often require multiple operators. To date, the DCE, the R-Scope, the IOP, and the Viacath system have data published relating to their application in human. Alternative forms of

  12. Comparative Evaluation of Physical and Structural Properties of Water Retted and Non-retted Flax Fibers

    Directory of Open Access Journals (Sweden)

    Vijaya Raghavan

    2013-10-01

    Full Text Available Flax stems of Modran variety were subjected to water retting under laboratory conditions and its physical properties were compared with non-retted fibers. Physical properties including percentage of impurities, weighted average length, linear density, tenacity and elongation were analyzed and the results were compared. The analysis of retted and non-retted flax fibers showed that retting is the most important step in the processing of flax fibers and it directly affects quality attributes like strength, fineness, and homogeneity. Scanning Electron microscope images of fibers were also analyzed and the retted fibers showed much cleaner surface when compared to decorticated non-retted fibers.

  13. Multi-Stress Monitoring System with Fiber-Optic Mandrels and Fiber Bragg Grating Sensors in a Sagnac Loop.

    Science.gov (United States)

    Kim, Hyunjin; Sampath, Umesh; Song, Minho

    2015-07-29

    Fiber Bragg grating sensors are placed in a fiber-optic Sagnac loop to combine the grating temperature sensors and the fiber-optic mandrel acoustic emission sensors in single optical circuit. A wavelength-scanning fiber-optic laser is used as a common light source for both sensors. A fiber-optic attenuator is placed at a specific position in the Sagnac loop in order to separate buried Bragg wavelengths from the Sagnac interferometer output. The Bragg wavelength shifts are measured with scanning band-pass filter demodulation and the mandrel output is analyzed by applying a fast Fourier transform to the interference signal. This hybrid-scheme could greatly reduce the size and the complexity of optical circuitry and signal processing unit, making it suitable for low cost multi-stress monitoring of large scale power systems.

  14. Routine colonic endoscopic evaluation following resolution of acute diverticulitis: Is it necessary?

    Science.gov (United States)

    Agarwal, Amit K; Karanjawala, Burzeen E; Maykel, Justin A; Johnson, Eric K; Steele, Scott R

    2014-01-01

    Diverticular disease incidence is increasing up to 65% by age 85 in industrialized nations, low fiber diets, and in younger and obese patients. Twenty-five percent of patients with diverticulosis will develop acute diverticulitis. This imposes a significant burden on healthcare systems, resulting in greater than 300000 admissions per year with an estimated annual cost of $3 billion USD. Abdominal computed tomography (CT) is the diagnostic study of choice, with a sensitivity and specificity greater than 95%. Unfortunately, similar CT findings can be present in colonic neoplasia, especially when perforated or inflamed. This prompted professional societies such as the American Society of Colon Rectal Surgeons to recommend patients undergo routine colonoscopy after an episode of acute diverticulitis to rule out malignancy. Yet, the data supporting routine colonoscopy after acute diverticulitis is sparse and based small cohort studies utilizing outdated technology. While any patient with an indication for a colonoscopy should undergo appropriate endoscopic evaluation, in the era of widespread use of high-resolution computed tomography, routine colonic endoscopic evaluation following resolution of acute uncomplicated diverticulitis poses additional costs, comes with inherent risks, and may require further study. In this manuscript, we review the current data related to this recommendation. PMID:25253951

  15. Fluorescence Endoscopy in vivo based on Fiber-bundle Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Zufiria, B.; Gomez-Garcia, P.; Stamatakis, K.; Vaquero, J.J.; Fresno, M.; Desco, M.; Ripoll, J.; Arranz, A.

    2016-07-01

    High-resolution imaging techniques have become important for the determination of the cellular organization that is coupled to organ function. In many cases the organ can be viewed without the need of ionizing radiation techniques in an easier way. This is the case of the gastrointestinal tract, an organ that can be directly accessed with endoscopy avoiding any invasive procedure. Here we describe the design, assembly and testing of a fluorescence high-resolution endoscope intended for the study of the cellular organization of the colon in an experimental mouse model of colon carcinoma. Access to the colon of the mouse took place using a fiber-optic bundle that redirects the light coming from a LED to produce fluorescence and detect it back through the fiber bundle. Results from in vivo and ex-vivo test using our fluorescence fiber bundle endoscope show altered tissue structure and destruction of the intestinal crypts in tumor-bearing areas compared with healthy tissue. (Author)

  16. Synthetic holography based on scanning microcavity

    Directory of Open Access Journals (Sweden)

    A. Di Donato

    2015-11-01

    Full Text Available Synthetic optical holography (SOH is an imaging technique, introduced in scanning microscopy to record amplitude and phase of a scattered field from a sample. In this paper, it is described a novel implementation of SOH through a lens-free low-coherence system, based on a scanning optical microcavity. This technique combines the low-coherence properties of the source with the mutual interference of scattered waves and the resonant behavior of a micro-cavity, in order to realize a high sensitive imaging system. Micro-cavity is compact and realized by approaching a cleaved optical fiber to the sample. The scanning system works in an open-loop configuration without the need for a reference wave, usually required in interferometric systems. Measurements were performed over calibration samples and a lateral resolution of about 1 μm is achieved by means of an optical fiber with a Numerical Aperture (NA equal to 0.1 and a Mode Field Diameter (MDF of 5.6 μm.

  17. PREOPERATIVE ENDOSCOPIC MARKING OF UNPALPABLE COLONIC TUMORS

    Directory of Open Access Journals (Sweden)

    A. L. Goncharov

    2013-01-01

    Full Text Available The identification of small colon lesions is one of the major problems in laparoscopic colonic resection.Research objective: to develop a technique of visualization of small tumors of a colon by preoperative endoscopic marking of a tumor.Materials and methods. In one day prior to operation to the patient after bowel preparation the colonoscopy is carried out. In the planned point near tumor on antimesentery edge the submucous infiltration of marking solution (Micky Sharpz blue tattoo pigment, UK is made. The volume of entered solution of 1–3 ml. In only 5 months of use of a technique preoperative marking to 14 patients with small (the size of 1–3 cm malignant tumors of the left colon is performed.Results. The tattoo mark was well visualized by during operation at 13 of 14 patients. In all cases we recorded no complications. Time of operation with preoperative marking averaged 108 min, that is significantly less in comparison with average time of operation with an intra-operative colonoscopy – 155 min (р < 0.001.Conclusions. The first experience of preoperative endoscopic marking of non palpable small tumors of a colon is encouraging. Performance of a technique wasn't accompanied by complications and allowed to reduce significantly time of operation and to simplify conditions of performance of operation.

  18. Endoscopic vs. tactile evaluation of subgingival calculus.

    Science.gov (United States)

    Osborn, Joy B; Lenton, Patricia A; Lunos, Scott A; Blue, Christine M

    2014-08-01

    Endoscopic technology has been developed to facilitate imagery for use during diagnostic and therapeutic phases of periodontal care. The purpose of this study was to compare the level of subgingival calculus detection using a periodontal endoscope with that of conventional tactile explorer in periodontitis subjects. A convenience sample of 26 subjects with moderate periodontitis in at least 2 quadrants was recruited from the University of Minnesota School of Dentistry to undergo quadrant scaling and root planing. One quadrant from each subject was randomized for tactile calculus detection alone and the other quadrant for tactile detection plus the Perioscope ™ (Perioscopy Inc., Oakland, Cali). A calculus index on a 0 to 3 score was performed at baseline and at 2 post-scaling and root planing visits. Sites where calculus was detected at visit 1 were retreated. T-tests were used to determine within-subject differences between Perioscope™ and tactile measures, and changes in measures between visits. Significantly more calculus was detected using the Perioscope™ vs. tactile explorer for all 3 subject visits (pcalculus detection from baseline to visit 1 were statistically significant for both the Perioscope™ and tactile quadrants (pcalculus detection from visit 1 to visit 2 was only significant for the Perioscope™ quadrant (pcalculus at this visit. It was concluded that the addition of a visual component to calculus detection via the Perioscope™ was most helpful in the re-evaluation phase of periodontal therapy. Copyright © 2014 The American Dental Hygienists’ Association.

  19. [Digital imaging and robotics in endoscopic surgery].

    Science.gov (United States)

    Go, P M

    1998-05-23

    The introduction of endoscopical surgery has among other things influenced technical developments in surgery. Owing to digitalisation, major progress will be made in imaging and in the sophisticated technology sometimes called robotics. Digital storage makes the results of imaging diagnostics (e.g. the results of radiological examination) suitable for transmission via video conference systems for telediagnostic purposes. The availability of digital video technique renders possible the processing, storage and retrieval of moving images as well. During endoscopical operations use may be made of a robot arm which replaces the camera man. The arm does not grow tired and provides a stable image. The surgeon himself can operate or address the arm and it can remember fixed image positions to which it can return if ordered to do so. The next step is to carry out surgical manipulations via a robot arm. This may make operations more patient-friendly. A robot arm can also have remote control: telerobotics. At the Internet site of this journal a number of supplements to this article can be found, for instance three-dimensional (3D) illustrations (which is the purpose of the 3D spectacles enclosed with this issue) and a quiz (http:@appendix.niwi. knaw.nl).

  20. [Conversional and endoscopic procedures following bariatric surgery].

    Science.gov (United States)

    Zorron, R; Bothe, C; Junghans, T; Pratschke, J; Benzing, C; Krenzien, F

    2016-10-01

    The Roux-en-Y gastric bypass (RYGB) is the therapy of choice in bariatric surgery. Sleeve gastrectomy and gastric banding are showing higher rates of treatment failure, reducing obesity-associated morbidity and body weight insufficiently. Moreover, gastroesophageal reflux disease (GERD) can occur refractory to medication. Therefore, a laparoscopic conversion to RYGB can be reasonable as long as specific conditions are fulfilled.Endoscopic procedures are currently being applied to revise bariatric procedures. Therapy failure following RYGB occurs in up to 20 % of cases. Transoral outlet reduction is the minimally invasive method of choice to reduce gastrojejunal anastomosis of the alimentary limb. The diameter of a gastric sleeve can be unwantedly enlarged as well; that can be reduced by placement of a longitudinal full-thickness suture.Severe hypoglycemic episodes can be present in patients following RYGB. Hypoglycemic episodes have to be diagnosed first and can be treated conventionally. Alternatively, a laparoscopic approach according to Branco-Zorron can be used for non-responders. Hypoglycemic episodes can thus be prevented and body weight reduction can be assured.Conversional and endoscopic procedures can be used in patients with treatment failure following bariatric surgery. Note that non-invasive approaches should have been applied intensively before a revisional procedure is performed.

  1. Endoscopic Endonasal Approach for a Suprasellar Craniopharyngioma.

    Science.gov (United States)

    Zenonos, Georgios A; Snyderman, Carl H; Gardner, Paul A

    2018-04-01

    Objectives  The current video presents the nuances of an endoscopic endonasal approach to a suprasellar craniopharyngioma. Design  The video analyzes the presentation, preoperative workup and imaging, surgical steps and technical nuances of the surgery, the clinical outcome, and follow-up imaging. Setting  The patient was treated by a skull base team consisting of a neurosurgeon and an ENT surgeon, at a teaching academic institution. Participants  The case refers to a 67-year-old man who presented with vision loss and headaches, and was found to have a suprasellar mass, with imaging characteristics consistent with a craniopharyngioma. Main Outcome Measures  The main outcome measures consistent of the reversal of the patient symptoms (vision loss and headaches), the recurrence-free survival based on imaging, as well as the absence of any complications. Results  The patient's vision improved after the surgery; at his last follow-up there was no evidence of recurrence on imaging. Conclusions  The endoscopic endonasal approach is safe and effective in treating suprasellar craniopharyngiomas. The link to the video can be found at: https://youtu.be/p1VXbwnAWCo .

  2. Emphysema. Imaging for endoscopic lung volume reduction

    International Nuclear Information System (INIS)

    Storbeck, B.; Oldigs, M.; Rabe, K.F.; Weber, C.; University Medical Center Hamburg-Eppendorf

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is characterized by two entities, the more airway-predominant type (''bronchitis'') on the one hand, and emphysema-predominant type on the other. Imaging via high-resolution computed tomography plays an important role in phenotyping COPD. For patients with advanced lung emphysema, new endoscopic lung volume reduction therapies (ELVR) have been developed. Proper selection of suitable patients requires thin-section reconstruction of volumetric CT image data sets also in coronal and sagittal orientation are required. In the current manuscript we will describe emphysema subtypes (centrilobular, paraseptal, panlobular), options for quantifying emphysema and this importance of regional distribution (homogeneous or heterogeneous, target area) as this is crucial for patient selection. Analysis of the interlobular fissures is obligatory despite the lack of standardization, as incomplete fissures indicate collateral ventilation (CV) via parenchymal bridges, which is an important criterion in choosing endoscopic methods of LVR. Every radiologist should be familiar with modern LVR therapies such as valves and coils, and furthermore should know what a lung doctor expects from radiologic evaluation (before and after ELVR). Finally we present a checklist as a quick reference for all steps concerning imaging for ELVR.

  3. Endoscopic Third Ventriculostomy in Previously Shunted Children

    Directory of Open Access Journals (Sweden)

    Eva Brichtova

    2013-01-01

    Full Text Available Endoscopic third ventriculostomy (ETV is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%. There were two serious complications (4.7%—one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically.

  4. Endoscopic third ventriculostomy for obstructive hydrocephalus

    International Nuclear Information System (INIS)

    Ali, M.; Usman, M.; Khan, Z.; Khan, K.M.; Hussain, R.; Khanzada, K.

    2013-01-01

    To determine the success rate of endoscopic third ventriculostomy (ETV) for treating obstructive hydrocephalus. Study Design: Cross-sectional observational study. Place and Duration of Study: The Neurosurgery Department of PGMI, Lady Reading Hospital, Peshawar, from May 2010 to November 2011. Methodology: Patients with obstructive hydrocephalus due to aqueductal stenosis, tectal and non-tectal tumour and already shunted patients for obstructive hydrocephalus presented with blocked shunt were included in the study. Patients with congenital hydrocephalus and secondary to meningitis were excluded. Endoscopic third ventriculostomy was performed. Success, complications and mortality was noted. Data was analyzed by descriptive statistics using SPSS software version 17. Results: There were 155 patients including 72 males and 83 females with ratio of 1: 1.33. Success rate was 71%. Indication of surgery was obstructive hydrocephalus due to aqueductal stenosis, posterior fossa tumour, brain stem and CP angle tumour. Complications were seen in 18 patients including mortality in 3 patients. Conclusion: ETV is effective, safe and successful procedure in patients with obstructive hydrocephalus. It may be used as replacement procedure of ventriculo-peritoneal shunt as initial line of management in selected patients. (author)

  5. Model PET Scan Activity

    Science.gov (United States)

    Strunk, Amber; Gazdovich, Jennifer; Redouté, Oriane; Reverte, Juan Manuel; Shelley, Samantha; Todorova, Vesela

    2018-05-01

    This paper provides a brief introduction to antimatter and how it, along with other modern physics topics, is utilized in positron emission tomography (PET) scans. It further describes a hands-on activity for students to help them gain an understanding of how PET scans assist in detecting cancer. Modern physics topics provide an exciting way to introduce students to current applications of physics.

  6. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ...

  8. Harmonic Contrast-Enhanced Endoscopic Ultrasonography for the Guidance of Fine-Needle Aspiration in Solid Pancreatic Masses

    DEFF Research Database (Denmark)

    Seicean, A; Badea, R; Moldovan-Pop, A

    2015-01-01

    Purpose: The global accuracy of fine-needle aspiration guided by endoscopic ultrasound (EUS-FNA) for pancreatic adenocarcinoma is about 85 %. The use of contrast agents during EUS to highlight vessels and the necrotic parts of pancreatic masses may improve biopsy guidance. Our aim was to assess...... whether the guidance of FNA by harmonic contrast-enhanced endoscopic ultrasound (CH-EUS) would increase diagnostic accuracy relative to conventional EUS-FNA in the same pancreatic masses. Patients and Methods: In a prospective study, EUS-FNA was performed in patients with pancreatic masses on CT scan......, followed by harmonic CH-EUS using SonoVue. A second cluster of CH-EUS-FNA was performed on contrast-enhanced images. The final diagnosis was based on the results of EUS-FNA and surgery, or the findings after 12 months' follow-up. Results: The final diagnosis was adenocarcinoma (n = 35), chronic...

  9. Current Innovations in Endoscopic Therapy for the Management of Colorectal Cancer: From Endoscopic Submucosal Dissection to Endoscopic Full-Thickness Resection

    Directory of Open Access Journals (Sweden)

    Shintaro Fujihara

    2014-01-01

    Full Text Available Endoscopic submucosal dissection (ESD is accepted as a minimally invasive treatment for colorectal cancer. However, due to technical difficulties and an increased rate of complications, ESD is not widely used in the colorectum. In some cases, endoscopic treatment alone is insufficient for disease control, and laparoscopic surgery is required. The combination of laparoscopic surgery and endoscopic resection represents a new frontier in cancer treatment. Recent developments in advanced polypectomy and minimally invasive surgical techniques will enable surgeons and endoscopists to challenge current practice in colorectal cancer treatment. Endoscopic full-thickness resection (EFTR of the colon offers the potential to decrease the postoperative morbidity and mortality associated with segmental colectomy while enhancing the diagnostic yield compared to current endoscopic techniques. However, closure is necessary after EFTR and natural transluminal endoscopic surgery (NOTES. Innovative methods and new devices for EFTR and suturing are being developed and may potentially change traditional paradigms to achieve minimally invasive surgery for colorectal cancer. The present paper aims to discuss the complementary role of ESD and the future development of EFTR. We focus on the possibility of achieving EFTR using the ESD method and closing devices.

  10. Transverse section scanning mechanism

    International Nuclear Information System (INIS)

    Doherty, E.J.

    1978-01-01

    Apparatus is described for scanning a transverse, radionuclide scan-field using an array of focussed collimators. The collimators are movable tangentially on rails, driven by a single motor via a coupled screw. The collimators are also movable in a radial direction on rails driven by a step motor via coupled screws and bevel gears. Adjacent bevel gears rotate in opposite directions so adjacent collimators move in radially opposite directions. In use, the focal point of each collimator scans at least half of the scan-field, e.g. a human head located in the central aperture, and the electrical outputs of detectors associated with each collimator are used to determine the distribution of radioactive emission intensity at a number of points in the scan-field. (author)

  11. LIDAR COMBINED SCANNING UNIT

    Directory of Open Access Journals (Sweden)

    V. V. Elizarov

    2016-11-01

    Full Text Available Subject of Research. The results of lidar combined scanning unit development for locating leaks of hydrocarbons are presented The unit enables to perform high-speed scanning of the investigated space in wide and narrow angle fields. Method. Scanning in a wide angular field is produced by one-line scanning path by means of the movable aluminum mirror with a frequency of 20Hz and amplitude of 20 degrees of swing. Narrowband scanning is performed along a spiral path by the deflector. The deflection of the beam is done by rotation of the optical wedges forming part of the deflector at an angle of ±50. The control function of the scanning node is performed by a specialized software product written in C# programming language. Main Results. This scanning unit allows scanning the investigated area at a distance of 50-100 m with spatial resolution at the level of 3 cm. The positioning accuracy of the laser beam in space is 15'. The developed scanning unit gives the possibility to browse the entire investigated area for the time not more than 1 ms at a rotation frequency of each wedge from 50 to 200 Hz. The problem of unambiguous definition of the beam geographical coordinates in space is solved at the software level according to the rotation angles of the mirrors and optical wedges. Lidar system coordinates are determined by means of GPS. Practical Relevance. Development results open the possibility for increasing the spatial resolution of scanning systems of a wide range of lidars and can provide high positioning accuracy of the laser beam in space.

  12. Transfer functions in collection scanning near-field optical microscopy

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Vohnsen, Brian; Bozhevolnaya, Elena A.

    1999-01-01

    are considered with respect to the relation between near-field optical images and the corresponding intensity distributions. Our conclusions are supported with numerical simulations and experimental results obtained by using a photon scanning tunneling microscope with an uncoated fiber tip....

  13. Nonlinear Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Hansen, Kim Per

    2004-01-01

    Despite the general recession in the global economy and the collapse of the optical telecommunication market, research within specialty fibers is thriving. This is, more than anything else, due to the technology transition from standard all-glass fibers to photonic crystal fibers, which, instead....... The freedom to design the dispersion profile of the fibers is much larger and it is possible to create fibers, which support only a single spatial mode, regardless of wavelength. In comparison, the standard dispersion-shifted fibers are limited by a much lower index-contrast between the core and the cladding...... in 1996, and are today on their way to become the dominating technology within the specialty fiber field. Whether they will replace the standard fiber in the more traditional areas like telecommunication transmission, is not yet clear, but the nonlinear photonic crystal fibers are here to stay....

  14. Optical Fiber Fusion Splicing

    CERN Document Server

    Yablon, Andrew D

    2005-01-01

    This book is an up-to-date treatment of optical fiber fusion splicing incorporating all the recent innovations in the field. It provides a toolbox of general strategies and specific techniques that the reader can apply when optimizing fusion splices between novel fibers. It specifically addresses considerations important for fusion splicing of contemporary specialty fibers including dispersion compensating fiber, erbium-doped gain fiber, polarization maintaining fiber, and microstructured fiber. Finally, it discusses the future of optical fiber fusion splicing including silica and non-silica based optical fibers as well as the trend toward increasing automation. Whilst serving as a self-contained reference work, abundant citations from the technical literature will enable readers to readily locate primary sources.

  15. Identification of tensile strength properties of abaca fiber by weakest-linkage approach-statistic property of fiber diameter

    Science.gov (United States)

    Suardi; Homma, H.; Abubakar

    2018-02-01

    Fiber reinforced plastics or metals (FRPor FRM) are usually ecological materials, because their specific strength defined as the strengthperunit mass is much larger than metal, and weight ofmachines and structuresfor transport made ofFRP can be significantly reduced so that the consumption of fossil fuel scan be saved to result in tremendous reduction of CO2emissions. However, when we consider life cycle assessment (LCA) of synthetic fibers like carbon fiber and glass fiber, we can recognize much CO2 emission in production of these fibers. Therefore, more ecological reinforcement fibers must be developed. For this end, we should utilization cellulose fibers derived from plant tissue structure as an alternative fibers for synthetic fibers, which are considered as carbon neutral materials, and natural degraded material. This study selectsabaca fiber, which is a natural fiber and is abundant in Indonesia, but its usagehas not been optimized for engineering material. The purpose of this study is to identify the mechanical strength of a single abaca fiber by statistical approach. First, weakest link theory and Weibull theory are used to discuss experimental data. 90 specimens of almost identical geometry and biological aspects are tested under tension. These data are analyzed by Weibull theory or other statistical theory. Final target is to look into optimal method to reduce scatter ratio, ratio of standard deviation to mean value, of less than 0.1, which is the level of metallic materials. If we can reduce scatter ration to such level, we can design machines and structures using abaca fiber in the same way as carbon fibers or glass fibers. Summary of Diameter Measurement the all mean value is 0.1 and standardeviasi. The t-Test showed that mean value of each part is estimated as sampling from group with the same mean value, at confidence level of 99%.

  16. Surgical management of failed endoscopic treatment of pancreatic disease.

    Science.gov (United States)

    Evans, Kimberly A; Clark, Colby W; Vogel, Stephen B; Behrns, Kevin E

    2008-11-01

    Endoscopic therapy of acute and chronic pancreatitis has decreased the need for operative intervention. However, a significant proportion of patients treated endoscopically require definitive surgical management for persistent symptoms. Our aim was to determine which patients are likely to fail with endoscopic therapy, and to assess the clinical outcome of surgical management. Patients were identified using ICD-9 codes for pancreatic disease as well as CPT codes for endoscopic therapy followed by surgery. Patients with documented acute or chronic pancreatitis treated endoscopically prior to surgical therapy were included (N = 88). The majority of patients (65%) exhibited chronic pancreatitis due to alcohol abuse. Common indicators for surgery were: persistent symptoms, anatomy not amenable to endoscopic treatment and unresolved common bile duct or pancreatic duct strictures. Surgical salvage procedures included internal drainage of a pseudocyst or an obstructed pancreatic duct (46%), debridement of peripancreatic fluid collections (25%), and pancreatic resection (31%). Death occurred in 3% of patients. The most common complications were hemorrhage (16%), wound infection (13%), and pulmonary complications (11%). Chronic pancreatitis with persistent symptoms is the most common reason for pancreatic surgery following endoscopic therapy. Surgical salvage therapy can largely be accomplished by drainage procedures, but pancreatic resection is common. These complex procedures can be performed with acceptable mortality but also with significant risk for morbidity.

  17. Gastroesophageal reflux disease. Scintigraphic, endoscopic and histologic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Kault, B.; Halvorsen, T.; Petersen, H.; Grette, K.; Myrvold, H.E.

    1986-01-01

    Radionucleotide scintigraphy and esophagoscopy with biopsy were carried out in 101 patients with symptoms strongly suggestive of gastroesophageal reflux (GER) disease. GER was visualized by scintigraphy in 86.1% of the patients. Endoscopic and histologic esophagitis were found in 68.1% and 58.4% of the patients, respectively, whereas both examinations taken together showed evidence of esophagitis in 82%. Histologic evidence of esophagitis was found in nearly all patients with severe endoscopic changes, and in 43.7% of the patients with no endoscopic abnormality. Scintigraphic reflux was demonstrated more frequently in the patients with severe endoscopic esophagitis (97.5%) than in those with no or only mild endoscopic changes (78.6%). Scintigraphic reflux was found in 91.5% and 78.5% of the patients with and without histologic evidence of esophagitis. 15 of the 18 patients (83.3%) without endoscopic and histologic abnormalities in the esophagus had scintigraphic evidence of reflux. The present study strongly supports the clinical significance of scintigraphy in GER disease and confirms that esophageal biopsy specimens increase the sensitivity of endoscopic evaluation. 31 refs.

  18. A Haptic Guided Robotic System for Endoscope Positioning and Holding.

    Science.gov (United States)

    Cabuk, Burak; Ceylan, Savas; Anik, Ihsan; Tugasaygi, Mehtap; Kizir, Selcuk

    2015-01-01

    To determine the feasibility, advantages, and disadvantages of using a robot for holding and maneuvering the endoscope in transnasal transsphenoidal surgery. The system used in this study was a Stewart Platform based robotic system that was developed by Kocaeli University Department of Mechatronics Engineering for positioning and holding of endoscope. After the first use on an artificial head model, the system was used on six fresh postmortem bodies that were provided by the Morgue Specialization Department of the Forensic Medicine Institute (Istanbul, Turkey). The setup required for robotic system was easy, the time for registration procedure and setup of the robot takes 15 minutes. The resistance was felt on haptic arm in case of contact or friction with adjacent tissues. The adaptation process was shorter with the mouse to manipulate the endoscope. The endoscopic transsphenoidal approach was achieved with the robotic system. The endoscope was guided to the sphenoid ostium with the help of the robotic arm. This robotic system can be used in endoscopic transsphenoidal surgery as an endoscope positioner and holder. The robot is able to change the position easily with the help of an assistant and prevents tremor, and provides a better field of vision for work.

  19. Iron Fibers Arrays Prepared by Electrodepositing in Reverse Liquid Crystalline

    Institute of Scientific and Technical Information of China (English)

    ZHAO Suling; LIN Dong; GUAN Jianguo; ZHANG Lianmeng

    2006-01-01

    Ordered iron fiber arrays were electrodeposited on the surface of zinc foils using "FeSO4 solution-sodium caprylate-Decanol" 3-component reverse hexagonal liquid crystal as soft templates. The structure of the soft templates and the synthesized iron fibers were characterized by polarizing microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis etc. The experimental results show that the synthesized iron fibers with α crystal phase grew up in the form of fiber clusters of about 200 nm along the direction perpendicular to the cathode surface. Each cluster was composed of several tens of fibers. The fibers had almost the same length of more than 10 μm with a diameter of about 50 nm.

  20. Environmental resistance and mechanical performance of basalt and glass fibers

    International Nuclear Information System (INIS)

    Wei Bin; Cao Hailin; Song Shenhua

    2010-01-01

    The treated basalt and glass fibers with sodium hydroxide and hydrochloric acid solutions for different times were analyzed, respectively. This paper summarized the mass loss ratio and the strength maintenance ratios of the fibers after treatment. The fibers' surface corrosion morphologies were characterized using scanning electron microscopy and their compositions were detected using energy dispersive X-ray spectroscopy. The acid resistance was much better than the alkali resistance for the basalt fibers. Nevertheless, for the glass fibers the situation is different: the acid resistance was almost the same as the alkali resistance. Among the two types of aqueous environments evaluated, the alkali solution is the most aggressive to the fibers' surface. The possible corrosion mechanisms are revealed.

  1. Amplitude-modulated fiber-ring laser

    DEFF Research Database (Denmark)

    Caputo, J. G.; Clausen, Carl A. Balslev; Sørensen, Mads Peter

    2000-01-01

    Soliton pulses generated by a fiber-ring laser are investigated by numerical simulation and perturbation methods. The mathematical modeling is based on the nonlinear Schrödinger equation with perturbative terms. We show that active mode locking with an amplitude modulator leads to a self......-starting of stable solitonic pulses from small random noise, provided the modulation depth is small. The perturbative analysis leads to a nonlinear coupled return map for the amplitude, phase, and position of the soliton pulses circulating in the fiber-ring laser. We established the validity of this approach...

  2. Laser Scanning in Forests

    Directory of Open Access Journals (Sweden)

    Håkan Olsson

    2012-09-01

    Full Text Available The introduction of Airborne Laser Scanning (ALS to forests has been revolutionary during the last decade. This development was facilitated by combining earlier ranging lidar discoveries [1–5], with experience obtained from full-waveform ranging radar [6,7] to new airborne laser scanning systems which had components such as a GNSS receiver (Global Navigation Satellite System, IMU (Inertial Measurement Unit and a scanning mechanism. Since the first commercial ALS in 1994, new ALS-based forest inventory approaches have been reported feasible for operational activities [8–12]. ALS is currently operationally applied for stand level forest inventories, for example, in Nordic countries. In Finland alone, the adoption of ALS for forest data collection has led to an annual savings of around 20 M€/year, and the work is mainly done by companies instead of governmental organizations. In spite of the long implementation times and there being a limited tradition of making changes in the forest sector, laser scanning was commercially and operationally applied after about only one decade of research. When analyzing high-ranked journal papers from ISI Web of Science, the topic of laser scanning of forests has been the driving force for the whole laser scanning research society over the last decade. Thus, the topic “laser scanning in forests” has provided a significant industrial, societal and scientific impact. [...

  3. Bone scan in pediatrics

    International Nuclear Information System (INIS)

    Gordon, I.; Peters, A.M.

    1987-01-01

    In 1984, a survey carried out in 21 countries in Europe showed that bone scintigraphy comprised 16% of all paediatric radioisotope scans. Although the value of bone scans in paediatrics is potentially great, their quality varies greatly, and poor-quality images are giving this valuable technique a bad reputation. The handling of children requires a sensitive staff and the provision of a few simple inexpensive items of distraction. Attempting simply to scan a child between two adult patients in a busy general department is a recipe for an unhappy, uncooperative child with the probable result of poor images. The intravenous injection of isotope should be given adjacent to the gamma camera room, unless dynamic scans are required, so that the child does not associate the camera with the injection. This injection is best carried out by someone competent in paediatric venipunture; the entire procedure should be explained to the child and parent, who should remain with child throughout. It is naive to think that silence makes for a cooperative child. The sensitivity of bone-seeking radioisotope tracers and the marked improvement in gamma camera resolution has allowed the bone scanning to become an integrated technique in the assessment of children suspected of suffering from pathological bone conditions. The tracer most commonly used for routine bone scanning is 99m Tc diphosphonate (MDP); other isotopes used include 99m Tc colloid for bone marrow scans and 67 Ga citrate and 111 In white blood cells ( 111 In WBC) for investigation of inflammatory/infective lesions

  4. Biliary and pancreatic stenting: Devices and insertion techniques in therapeutic endoscopic retrograde cholangiopancreatography and endoscopic ultrasonography

    Science.gov (United States)

    Mangiavillano, Benedetto; Pagano, Nico; Baron, Todd H; Arena, Monica; Iabichino, Giuseppe; Consolo, Pierluigi; Opocher, Enrico; Luigiano, Carmelo

    2016-01-01

    Stents are tubular devices made of plastic or metal. Endoscopic stenting is the most common treatment for obstruction of the common bile duct or of the main pancreatic duct, but also employed for the treatment of bilio-pancreatic leakages, for preventing post- endoscopic retrograde cholangiopancreatography pancreatitis and to drain the gallbladder and pancreatic fluid collections. Recent progresses in techniques of stent insertion and metal stent design are represented by new, fully-covered lumen apposing metal stents. These stents are specifically designed for transmural drainage, with a saddle-shape design and bilateral flanges, to provide lumen-to-lumen anchoring, reducing the risk of migration and leakage. This review is an update of the technique of stent insertion and metal stent deployment, of the most recent data available on stent types and characteristics and the new applications for biliopancreatic stents. PMID:26862364

  5. Endoscopic submucosal dissection for early Barrett's neoplasia.

    Science.gov (United States)

    Barret, Maximilien; Cao, Dalhia Thao; Beuvon, Frédéric; Leblanc, Sarah; Terris, Benoit; Camus, Marine; Coriat, Romain; Chaussade, Stanislas; Prat, Frédéric

    2016-04-01

    The possible benefit of endoscopic submucosal dissection (ESD) for early neoplasia arising in Barrett's esophagus remains controversial. We aimed to assess the efficacy and safety of ESD for the treatment of early Barrett's neoplasia. All consecutive patients undergoing ESD for the resection of a visible lesion in a Barrett's esophagus, either suspicious of submucosal infiltration or exceeding 10 mm in size, between February 2012 and January 2015 were prospectively included. The primary endpoint was the rate of curative resection of carcinoma, defined as histologically complete resection of adenocarcinomas without poor histoprognostic factors. Thirty-five patients (36 lesions) with a mean age of 66.2 ± 12 years, a mean ASA score of 2.1 ± 0.7, and a mean C4M6 Barrett's segment were included. The mean procedure time was 191 ± 79 mn, and the mean size of the resected specimen was 51.3 ± 23 mm. En bloc resection rate was 89%. Lesions were 12 ± 15 mm in size, and 81% (29/36) were invasive adenocarcinomas, six of which with submucosal invasion. Although R0 resection of carcinoma was 72.4%, the curative resection rate was 66% (19/29). After a mean follow-up of 12.9 ± 9 months, 16 (45.7%) patients had required additional treatment, among whom nine underwent surgical resection, and seven further endoscopic treatments. Metachronous lesions or recurrence of cancer developed during the follow-up period in 17.2% of the patients. The overall complication rate was 16.7%, including 8.3% perforations, all conservatively managed, and no bleeding. The 30-day mortality was 0%. In this early experience, ESD yielded a moderate curative resection rate in Barrett's neoplasia. At present, improvements are needed if ESD is to replace piecemeal endoscopic mucosal resection in the management of Barrett's neoplasia.

  6. Endoscopic burr hole evacuation of an acute subdural hematoma.

    Science.gov (United States)

    Codd, Patrick J; Venteicher, Andrew S; Agarwalla, Pankaj K; Kahle, Kristopher T; Jho, David H

    2013-12-01

    Acute subdural hematoma evacuations frequently necessitate large craniotomies with extended operative times and high relative blood loss, which can lead to additional morbidity for the patient. While endoscopic minimally invasive approaches to chronic subdural collections have been successfully demonstrated, this technique has not previously been applied to acute subdural hematomas. The authors report their experience with an 87-year-old patient presenting with a large acute right-sided subdural hematoma successfully evacuated via an endoscopic minimally invasive technique. The operative approach is outlined, and the literature on endoscopic subdural collection evacuation reviewed. Copyright © 2013. Published by Elsevier Ltd.

  7. A Lethal Complication of Endoscopic Therapy: Duodenal Intramural Hematoma

    Directory of Open Access Journals (Sweden)

    Turan Calhan

    2015-01-01

    Full Text Available Duodenal intramural hematoma (DIH usually occurs in childhood and young adults following blunt abdominal trauma. It may also develop in the presence of coagulation disorders and may rarely be an iatrogenic outcome of endoscopic procedures. Management of DIH is usually a conservative approach. A case of intramural duodenal hematoma that developed following endoscopic epinephrine sclerotherapy and/or argon plasma coagulation and that was nonresponsive to conservative therapy in a patient with chronic renal failure who died from sepsis is being discussed in this report. Clinicians should be aware of such possible complications after endoscopic hemostasis in patients with coagulation disorders.

  8. Endoscopic surgery of the nose and paranasal sinus.

    Science.gov (United States)

    Palmer, Orville; Moche, Jason A; Matthews, Stanley

    2012-05-01

    Mucosal preservation is of paramount importance in the diagnosis and surgical management of the sinonasal tract. The endoscope revolutionized the practice of endoscopic nasal surgery. As a result, external sinus surgery is performed less frequently today, and more emphasis is placed on functional endoscopy and preservation of normal anatomy. Endoscopic surgery of the nose and paranasal sinus has provided improved surgical outcomes and has shortened the length of stay in hospital. It has also become a valuable teaching tool. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. [Endoscopic sphincterotomy in choledocholithiasis and an intact gallbladder].

    Science.gov (United States)

    Vladimirov, B; Petkov, R; Viiachki, I; Damianov, D; Iarŭmov, N

    1996-01-01

    Endoscopic sphincterotomy (ES) with extraction of calculi is a basic method of treating choledocholithiasis in post-cholecystectomy patients (8, 9). Endoscopic treatment contributes to a considerable reduction of the indications for reoperation. The existing views concerning ES done in patients with preserved gallbladder, especially in the era of laparoscopic surgery, are still conflicting (3, 6). There are several options: cholecystectomy with removal of calculi in the common bile duct by ES in a subsequent stage, or vice versa-primary ES with ensuring cholecystectomy. The undertaking of independent surgical or endoscopic treatment is likewise practicable (2, 6).

  10. Surgical stress response: does endoscopic surgery confer an advantage?

    DEFF Research Database (Denmark)

    Kehlet, H

    1999-01-01

    of postoperative pulmonary function and less hypoxemia with endoscopic operation. The slight modification of surgical stress responses by endoscopic surgery is in contrast to the common, though not universal, demonstration of less pain, shorter hospital stay, and less morbidity after endoscopic surgery...... operations where differences are more likely to be found. The clinical consequences of these findings in relation to all over surgical outcome remain to be defined, but effective pain treatment, stress reduction by other techniques, and provision of an active rehabilitation program with early mobilization...

  11. Preparation of TiO2 hollow fibers using poly(vinylidene fluoride) hollow fiber microfiltration membrane as a template

    International Nuclear Information System (INIS)

    Lu Haiqiang; Zhang Lixiong; Xing Weihong; Wang Huanting; Xu Nanping

    2005-01-01

    TiO 2 hollow fibers were successfully prepared by using poly(vinylidene fluoride) hollow fiber microfiltration membrane as a template. The preparation procedure includes repeated impregnation of the TiO 2 precursor in the pores of the polymeric membrane, and calcination to burn off the template, producing the TiO 2 hollow fibers. The TiO 2 hollow fibers were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). TiO 2 hollow fibers with other structures, such as honeycomb monolith and spring, were also prepared by preshaping the polymeric membranes into the honeycomb structure and spring, respectively. The phase structure of the TiO 2 hollow fibers could be readily adjusted by changing the calcination temperature

  12. A comparison of microdebrider assisted endoscopic sinus surgery and conventional endoscopic sinus surgery for nasal polypi.

    Science.gov (United States)

    Singh, Rohit; Hazarika, Produl; Nayak, Dipak Ranjan; Balakrishnan, R; Gangwar, Navneeta; Hazarika, Manali

    2013-07-01

    Nasal polyposis is often encountered in rhinology practice. Those who fail conservative management, a definitive surgery is essential to achieve sufficient ventilation and drainage of the affected sinuses by using either microdebrider or conventional instruments for functional endoscopic sinus surgery (FESS). A prospective study was conducted on 40 cases of nasal polypi in a tertiary care hospital. 20 cases were operated by conventional endoscopic instruments and 20 using the microdebrider. The study aimed at comparing the intra operative (blood loss, duration of surgery) and post operative results (crusting, scarring, discharge, symptoms, recurrence) between the two groups using Lund-Mackay scoring system and the data was statistically analysed. There was no statistically significant difference in surgical outcome for patients when either conventional endoscopic instruments or microdebrider was used. However, there was a significant symptomatic improvement in cases undergoing microdebrider FESS. Microdebrider assisted polypectomy is precise, relatively bloodless surgery though the precision depends on the surgeon's anatomical knowledge and operative skills. Study substantiates that these instruments are helpful but not a prerequisite for successful outcomes in FESS. The study re-emphasises the utility of the microdebrider to young learning FESS surgeons.

  13. Ceramic fiber reinforced filter

    Science.gov (United States)

    Stinton, David P.; McLaughlin, Jerry C.; Lowden, Richard A.

    1991-01-01

    A filter for removing particulate matter from high temperature flowing fluids, and in particular gases, that is reinforced with ceramic fibers. The filter has a ceramic base fiber material in the form of a fabric, felt, paper of the like, with the refractory fibers thereof coated with a thin layer of a protective and bonding refractory applied by chemical vapor deposition techniques. This coating causes each fiber to be physically joined to adjoining fibers so as to prevent movement of the fibers during use and to increase the strength and toughness of the composite filter. Further, the coating can be selected to minimize any reactions between the constituents of the fluids and the fibers. A description is given of the formation of a composite filter using a felt preform of commercial silicon carbide fibers together with the coating of these fibers with pure silicon carbide. Filter efficiency approaching 100% has been demonstrated with these filters. The fiber base material is alternately made from aluminosilicate fibers, zirconia fibers and alumina fibers. Coating with Al.sub.2 O.sub.3 is also described. Advanced configurations for the composite filter are suggested.

  14. Steel fiber reinforced concrete

    International Nuclear Information System (INIS)

    Baloch, S.U.

    2005-01-01

    Steel-Fiber Reinforced Concrete is constructed by adding short fibers of small cross-sectional size .to the fresh concrete. These fibers reinforce the concrete in all directions, as they are randomly oriented. The improved mechanical properties of concrete include ductility, impact-resistance, compressive, tensile and flexural strength and abrasion-resistance. These uniqlte properties of the fiber- reinforcement can be exploited to great advantage in concrete structural members containing both conventional bar-reinforcement and steel fibers. The improvements in mechanical properties of cementitious materials resulting from steel-fiber reinforcement depend on the type, geometry, volume fraction and material-properties of fibers, the matrix mix proportions and the fiber-matrix interfacial bond characteristics. Effects of steel fibers on the mechanical properties of concrete have been investigated in this paper through a comprehensive testing-programme, by varying the fiber volume fraction and the aspect-ratio (Lid) of fibers. Significant improvements are observed in compressive, tensile, flexural strength and impact-resistance of concrete, accompanied by marked improvement in ductility. optimum fiber-volume fraction and aspect-ratio of steel fibers is identified. Test results are analyzed in details and relevant conclusions drawn. The research is finally concluded with future research needs. (author)

  15. Ling classification describes endoscopic progressive process of achalasia and successful peroral endoscopy myotomy prevents endoscopic progression of achalasia.

    Science.gov (United States)

    Zhang, Wen-Gang; Linghu, En-Qiang; Chai, Ning-Li; Li, Hui-Kai

    2017-05-14

    To verify the hypothesis that the Ling classification describes the endoscopic progressive process of achalasia and determine the ability of successful peroral endoscopic myotomy (POEM) to prevent endoscopic progression of achalasia. We retrospectively reviewed the endoscopic findings, symptom duration, and manometric data in patients with achalasia. A total of 359 patients (197 women, 162 men) with a mean age of 42.1 years (range, 12-75 years) were evaluated. Symptom duration ranged from 2 to 360 mo, with a median of 36 mo. Patients were classified with Ling type I ( n = 119), IIa ( n = 106), IIb ( n = 60), IIc ( n = 60), or III ( n = 14), according to the Ling classification. Of the 359 patients, 349 underwent POEM, among whom 21 had an endoscopic follow-up for more than 2 years. Pre-treatment and post-treatment Ling classifications of these 21 patients were compared. Symptom duration increased significantly with increasing Ling classification (from I to III) ( P achalasia and may be able to serve as an endoscopic assessment criterion for achalasia. Successful POEM (Eckardt score ≤ 3) seems to have the ability to prevent endoscopic evolvement of achalasia. However, studies with larger populations are warranted to confirm our findings.

  16. Endoscopic management of intraoperative small bowel laceration during natural orifice translumenal endoscopic surgery: a blinded porcine study.

    Science.gov (United States)

    Fyock, Christopher J; Forsmark, Chris E; Wagh, Mihir S

    2011-01-01

    Natural orifice translumenal endoscopic surgery (NOTES) has recently gained great enthusiasm, but there is concern regarding the ability to endoscopically manage complications purely via natural orifices. To assess the feasibility of endoscopically managing enteral perforation during NOTES using currently available endoscopic accessories. Twelve pigs underwent transgastric or transcolonic endoscopic exploration. Full-thickness enterotomies were intentionally created to mimic accidental small bowel lacerations during NOTES. These lacerations were then closed with endoclips. In the blinded arm of the study, small bowel repair was performed by a second blinded endoscopist. Adequate closure of the laceration was confirmed with a leak test. Primary access sites were closed with endoclips or T-anchors. At necropsy, the peritoneal cavity was inspected for abscesses, bleeding, or damage to surrounding structures. The enterotomy site was examined for adequacy of closure, adhesions, or evidence of infection. Fifteen small bowel lacerations were performed in 12 animals. Successful closure was achieved in all 10 cases in the nonblinded arm. Survival animals had an uncomplicated postoperative course and all enterotomy sites were well healed without evidence of necrosis, adhesions, abscess, or bleeding at necropsy. Leak test was negative in all animals. In the blinded arm, both small intestinal lacerations could not be identified by the blinded endoscopist. Necropsy revealed open small bowel lacerations. Small intestinal injuries are difficult to localize with currently available flexible endoscopes and accessories. Endoscopic clips, however, may be adequate for closure of small bowel lacerations if the site of injury is known.

  17. Preparation and characterization of corn reinforced polymer sheet of fibers

    International Nuclear Information System (INIS)

    Moreira, Tatiana Martinez; Seo, Emilia Satoshi Miyamaru

    2016-01-01

    There is a global trend in seeking plant fibers to replace the synthetic fibers to obtain reinforced composites aimed at the use of renewable resources. In this context, this paper aims to develop the process of preparing maize leaf fibers, characterizing them and adapting them for applications in the construction industry and develop a reinforced polymer composite with these fibers. Corn leaves were dried in environmental temperature, treated by mercerizing, then neutralized with acid solution and washed in running water. The characterization of the corn leaf fibers was carried out by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, specific surface area, thermogravimetry and specific mass. The mercerizing treatment was effective, because the maize fibers have characteristics similar to synthetic fibers, leading to a possibility of new technological uses. The polymeric composite material was developed by extrusion processes and injection and tested for tensile testing, differential scanning calorimetry and scanning electron microscopy, thus reused an organic waste that would be disposed of by inserting it in a technological process, contributing to the research and development of new polymeric materials as well as to reduce waste discarded as scrap. (author)

  18. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... for a thyroid scan is 30 minutes or less. Thyroid Uptake You will be given radioactive iodine ( ... for each thyroid uptake is five minutes or less. top of page What will I experience during ...

  19. Thyroid Scan and Uptake

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    Full Text Available ... evaluate changes in the gland following medication use, surgery, radiotherapy or chemotherapy top of page How should ... such as an x-ray or CT scan, surgeries or treatments using iodinated contrast material within the ...

  20. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... abnormal was found, and should not be a cause of concern for you. If you had an ... abnormal was found, and should not be a cause of concern for you. Actual scanning time for ...

  1. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Details are given of a tomographic scanning apparatus, with particular reference to a multiplexer slip ring means for receiving output from the detectors and enabling interfeed to the image reconstruction station. (U.K.)

  2. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Details are presented of a tomographic scanning apparatus, its rotational assembly, and the control and circuit elements, with particular reference to the amplifier and multiplexing circuits enabling detector signal calibration. (U.K.)

  3. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    This patent specification relates to a tomographic scanning apparatus using a fan beam and digital output signal, and particularly to the design of the gas-pressurized ionization detection system. (U.K.)

  4. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  5. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... which are encased in metal and plastic and most often shaped like a box, attached to a ... will I experience during and after the procedure? Most thyroid scan and thyroid uptake procedures are painless. ...

  6. Heart CT scan

    Science.gov (United States)

    ... make to decrease the risk of heart disease. Risks Risks of CT scans include: Being exposed to ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... often unattainable using other imaging procedures. For many diseases, nuclear medicine scans yield the most useful information ...

  8. Thyroid Scan and Uptake

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    Full Text Available ... A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is ... thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that uses ...

  9. Thyroid Scan and Uptake

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    Full Text Available ... that help physicians diagnose and evaluate medical conditions. These imaging scans use radioactive materials called radiopharmaceuticals or ... or had thyroid cancer. A physician may perform these imaging tests to: determine if the gland is ...

  10. Thyroid Scan and Uptake

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    Full Text Available ... Because nuclear medicine procedures are able to pinpoint molecular activity within the body, they offer the potential ... or imaging device that produces pictures and provides molecular information. The thyroid scan and thyroid uptake provide ...

  11. Thyroid Scan and Uptake

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    Full Text Available ... Actual scanning time for each thyroid uptake is five minutes or less. top of page What will ... diagnostic procedures have been used for more than five decades, and there are no known long-term ...

  12. Thyroid Scan and Uptake

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    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top ... Scan and Uptake Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  13. Thyroid Scan and Uptake

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    Full Text Available ... often unattainable using other imaging procedures. For many diseases, nuclear medicine scans yield the most useful information needed to make a diagnosis or to determine appropriate treatment, if any. Nuclear medicine is less expensive and ...

  14. Thyroid Scan and Uptake

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    Full Text Available ... the gamma camera and single-photon emission-computed tomography (SPECT). The gamma camera, also called a scintillation ... high as with other imaging techniques, such as CT or MRI. However, nuclear medicine scans are more ...

  15. Scanning Auger Electron Microscope

    Data.gov (United States)

    Federal Laboratory Consortium — A JEOL model 7830F field emission source, scanning Auger microscope.Specifications / Capabilities:Ultra-high vacuum (UHV), electron gun range from 0.1 kV to 25 kV,...

  16. Thyroid Scan and Uptake

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    Full Text Available ... as an overactive thyroid gland, a condition called hyperthyroidism , cancer or other growths assess the nature of ... an x-ray or CT scan, surgeries or treatments using iodinated contrast material within the last two ...

  17. Thyroid Scan and Uptake

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    Full Text Available ... painless. However, during the thyroid scan, you may feel uncomfortable when lying completely still with your head ... When the radiotracer is given intravenously, you will feel a slight pin prick when the needle is ...

  18. Thyroid Scan and Uptake

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    Full Text Available ... energy. top of page What are some common uses of the procedure? The thyroid scan is used ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  19. Thyroid Scan and Uptake

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    Full Text Available ... scan and thyroid uptake provide information about the structure and function of the thyroid. The thyroid is ... computer, create pictures offering details on both the structure and function of organs and tissues in your ...

  20. Thyroid Scan and Uptake

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    Full Text Available ... found, and should not be a cause of concern for you. If you had an intravenous line ... found, and should not be a cause of concern for you. Actual scanning time for each thyroid ...