WorldWideScience

Sample records for ahmed tube insertion

  1. Graft-free Ahmed tube insertion: a modified method at 5 mm from limbus

    Directory of Open Access Journals (Sweden)

    Juan Carlos Mesa-Gutiérrez

    2010-04-01

    Full Text Available Juan Carlos Mesa-Gutiérrez, Juan Lillo-Sopena, Anna Monés-Llivina, Silvia Sanz-Moreno, Jorge Arruga-GinebredaDepartment of Ophthalmology, Hospital Universitari de Bellvitge, L’Hospitalet de Llobregat, Barcelona, SpainObjective: To determine the medium-term outcome of Ahmed implants inserted through a needle tract at 5 mm from limbus that eliminates the need for a donor scleral graft.Methods: A retrospective case series of 19 patients undergoing Ahmed implant surgery for refractory glaucoma with a mean follow-up of 12 months. Primary outcome measures included control of intraocular pressure after surgery. Secondary outcome measure included the frequency of intraoperative and postoperative complications.Results: Intraocular pressure was maintained between 6 and 21 mmHg throughout the study. There was no postoperative hypotony. There were no complications related to this modified technique.Conclusion: Needle tract at 5 mm from limbus maintains implant’s ability to control intraocular pressure and eliminates the need for a donor scleral graft or heterologous material.Keywords: surgical technique, Ahmed implant, refractory glaucoma, donor scleral graft, tube shunt device

  2. Ahmed glaucoma valve implantation with tube insertion through the ciliary sulcus in pseudophakic/aphakic eyes.

    Science.gov (United States)

    Eslami, Yadolla; Mohammadi, Massood; Fakhraie, Ghasem; Zarei, Reza; Moghimi, Sasan

    2014-02-01

    To report the efficacy and safety of Ahmed glaucoma valve (AGV) insertion into the ciliary sulcus in pseudophakic/aphakic patients. A chart review was done on patients with uncontrolled glaucoma, who underwent AGV implantation with tube inserted into the ciliary sulcus. Baseline intraocular pressure (IOP) and number of medications were compared with that of postoperative follow-up visits. Surgical success was defined as last IOP glaucoma control, and without loss of light perception. Postoperative complications were recorded. Twenty-three eyes of 23 patients were recruited with the mean follow-up of 9 months (range, 3 to 24 mo). The mean (SD) age of patients was 49.9 (16.9) years (range, 22 to 80 years). The mean (SD) IOP (mm Hg) was reduced from 37.9 (12.4) before surgery to 16.2 (3.6) at the last follow-up visit (P<0.001). The mean (SD) number of medications was reduced from 3.3 (0.9) preoperatively to 1 (1.1) at the last follow-up (P<0.001). Success rate was 18/23 (78.6%). Complications included endophthalmitis in 1 eye, tube exposure in 1 diabetic patient, and vitreous tube occlusion in 1 eye. No case of corneal decompensation or graft failure was seen during follow-up. Ciliary sulcus placement of the tube of AGV effectively reduces IOP and medication use in short term. It has the potential to lower corneal complications of anterior chamber tube insertion and avoids the need for pars plana vitrectomy and tube insertion in patients at higher risk of corneal decompensation.

  3. Chest tube insertion

    Science.gov (United States)

    Chest drainage tube insertion; Insertion of tube into chest; Tube thoracostomy; Pericardial drain ... Be careful there are no kinks in your tube. The drainage system should always sit upright and be placed ...

  4. Feeding tube insertion - gastrostomy

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002937.htm Feeding tube insertion - gastrostomy To use the sharing features on this page, please enable JavaScript. A gastrostomy feeding tube insertion is the placement of a feeding ...

  5. Chest tube insertion - series (image)

    Science.gov (United States)

    Chest tubes are inserted to drain blood, fluid, or air and allow full expansion of the lungs. The tube is placed in the pleural space. The area where the tube will be inserted is numbed (local anesthesia). The patient may also be sedated. The chest ...

  6. Combined Glaucoma Tube Shunt (Ahmed) and Fluocinolone Acetonide (Retisert™) Implantation Compared to Ahmed Alone in Uveitic Glaucoma.

    Science.gov (United States)

    Zivney, Mark; Lin, Phoebe; Edmunds, Beth; Parikh, Mansi; Takusagawa, Hana; Tehrani, Shandiz

    2016-12-01

    Glaucoma is a known complication of uveitis, and may require glaucoma tube shunt implantation for intraocular pressure (IOP) control. The success of glaucoma tube shunt implantation in the setting of a local ocular steroid depot in uveitic glaucoma remains unknown. The purpose of this study was to determine whether patients who underwent combined glaucoma tube shunt (Ahmed) and fluocinolone acetonide (Retisert™, Bausch + Lomb, Bridgewater, NJ, USA) implantation have superior outcomes compared to patients with Ahmed implants only in the setting of uveitic glaucoma. All participants were studied retrospectively and underwent Ahmed implantation alone or with existing/concurrent Retisert implantation (combined group) at a single academic institution. The main outcome measures were IOP, visual acuity (VA), number of IOP-lowering medications, and adverse events at 6 months after Ahmed implantation. Secondary outcome measures included adverse events and surgical success at 6 months after Ahmed implantation. Mean IOP at 6 months after Ahmed implantation was 15.3 ± 4.8 and 15.1 ± 4.9 mm Hg in the Ahmed only group (n = 17) and the combined group (n = 17), respectively (p = 0.89). The mean number of IOP-lowering medications at 6 months after Ahmed implantation was 1.7 ± 1.0 and 1.8 ± 1.0 in the Ahmed only group and the combined group, respectively (p = 0.86). Mean VA at 6 months after Ahmed implantation was 0.35 ± 0.29 and 0.42 ± 0.33 log mean angle of resolution in the Ahmed only group and the combined group, respectively (p = 0.50). No significant differences in surgical success or adverse events were noted between the two groups. At 6 months, no significant differences in mean IOP, mean number of IOP-lowering medications, VA, surgical success, or adverse events were noted between Ahmed implantation alone or combined Ahmed and Retisert implantation in patients with uveitic glaucoma.

  7. Effect of glaucoma tube shunt parameters on cornea endothelial cells in patients with Ahmed valve implants.

    Science.gov (United States)

    Koo, Euna B; Hou, Jing; Han, Ying; Keenan, Jeremy D; Stamper, Robert L; Jeng, Bennie H

    2015-01-01

    The aim of this study was to assess the effect of various tube parameters on corneal endothelial cell density (ECD) after insertion of Ahmed valves. Thirty-nine eyes of 33 patients with previous superotemporal (ST) Ahmed valve implantation and 20 eyes of 13 participants with previous uncomplicated phacoemulsification and intraocular lens implantation but no history of glaucoma surgery were evaluated. Various tube parameters were measured with anterior segment optical coherence tomography. ST, central, and inferonasal (IN) ECD and pachymetry were measured. Endothelial cell loss and corneal thickness in the ST cornea was compared with those in the IN cornea. The mean age of the operated patients was 58 ± 22 years, and the mean time since glaucoma surgery was 2.5 ± 2.6 years. Thirty-two of the 39 study eyes were pseudophakic. The ECD was significantly lower in the ST endothelium than in the IN endothelium in eyes with glaucoma tube surgery (P < 0.001), although this relative reduction in ST ECD was not greater than that seen in pseudophakic control eyes (P = 0.16). In univariate analysis, tube angle relative to the cornea and distance from the tip of the tube to the cornea were significant risk factors for decreased ST endothelial cell loss when assessed relative to the IN ECD (P = 0.01 and P = 0.02, respectively). In multivariate analysis, only the distance of the tube tip to the cornea remained significantly associated with ST endothelial cell loss. Although this was a retrospective study with inherent limitations, tubes that are closer to the cornea seem to lead to increased loss of adjacent endothelial cells.

  8. Surgical Outcomes of Ahmed or Baerveldt Tube Shunt Implantation for medically Uncontrolled Traumatic Glaucoma.

    Science.gov (United States)

    Yadgarov, Arkadiy; Liu, Dan; Crane, Elliot S; Khouri, Albert S

    2017-01-01

    To describe postoperative surgical success of either Ahmed or Baerveldt tube shunt implantation for eyes with medically uncontrolled traumatic glaucoma. A review was carried out to identify patients with traumatic glaucoma that required tube shunt implantation between 2009 and 2015 at Rutgers University in Newark, New Jersey, USA. Seventeen eyes from 17 patients met inclusion criteria, including at least 3-month postoperative follow-up. The main outcome measure was surgical success at 1-year follow-up after tube implantation. Mean preoperative intraocular pressure (IOP) was 34.1 ± 8.2 mm Hg on 3.1 ± 1.6 ocular hypotensive medications. Nine eyes (53%) sustained closed globe injury. Ten eyes (59%) received an Ahmed valve shunt and seven eyes (41%) received a Baerveldt tube shunt. Surgical success rate at 1 year postoperatively was 83%. Compared to preoperative, the mean postoperative IOP was significantly lower (16.1 ± 3.5 mm Hg, p Ahmed or Baerveldt tube shunt provided successful control of IOP in patients with medically uncontrollable traumatic glaucoma. Yadgarov A, Liu D, Crane ES, Khouri AS. Surgical Outcomes of Ahmed or Baerveldt Tube Shunt Implantation for medically Uncontrolled Traumatic Glaucoma. J Curr Glaucoma Pract 2017;11(1):16-21.

  9. Laparoscopic insertion of the Moss feeding tube.

    Science.gov (United States)

    Albrink, M H; Hagan, K; Rosemurgy, A S

    1993-12-01

    Placement of enteral feeding tubes is an important part of a surgeon's skill base. Surgical insertion of feeding tubes has been performed safely for many years with very few modifications. With the recent surge in interest and applicability of other laparoscopic procedures, it is well within the skills of the average laparoscopic surgeon to insert feeding tubes. We describe herein a simple technique for the insertion of the Moss feeding tube. The procedure described has a minimum of invasion, along with simplicity, safety, and accuracy.

  10. Evaluation of the tightness of contact between 
limbal sclera tunnel and tube following Ahmed 
glaucoma valve implantation.

    Science.gov (United States)

    Holló, Gábor; Naghizadeh, Farzaneh

    2013-01-01

    To investigate whether the tightness of contact between the tube and the limbal sclera tunnel can be evaluated with high-magnification anterior segment optical coherence tomography (OCT) imaging following Ahmed glaucoma valve implantation. Tightness between the tube and the limbal sclera tunnel was investigated with the CAM-L cornea lens adapter of the Optovue Fourier-domain OCT (RTVue-OCT) for 21 uncomplicated Ahmed glaucoma valves implanted in 20 eyes of 19 patients with glaucoma. Nineteen valves were implanted 4 to 124 months earlier (late postoperative cases) and 2 valves 1 day prior to the imaging (early postoperative cases). All valves were introduced into the anterior chamber via a limbal sclera tunnel. The limbal intratunnel part of the tube was successfully imaged in all but 2 cases where an additional full-thickness sclera patch was used. In 14 cases, the contact was tight without tube compression. In 
5 cases, the tube was partially compressed but remained open in the limbal sclera tunnel, and redilated behind the limbus. No case with loose contact or peritubular filtration was seen. The posterior run of the tube was successfully imaged in all 19 cases without a full-thickness sclera patch. High-magnification imaging with the CAM- L anterior segment adapter of the RTVue-OCT allows detailed examination of the limbal insertion area of tubes in both the early and late postoperative periods. Therefore this method may potentially be applied for detection of complications related to tube insertion after glaucoma drainage device surgery.

  11. Efficacy and safety of the pars plana clip in the Ahmed valve device inserted via the pars plana in patients with refractory glaucoma

    Directory of Open Access Journals (Sweden)

    Manuel Diaz-Llopis

    2010-05-01

    Full Text Available Manuel Diaz-Llopis1,2,3, David Salom1,3, Salvador García-Delpech1,2,3, Patricia Udaondo1,3, Jose Maria Millan3,5, J Fernando Arevalo61Department of Ophthalmology, La Fe University Hospital of Valencia, Valencia, Spain; 2Department of Ophthalmology of the Valencia University, Valencia, Spain; 3Biomedical Network Research Centre on Rare Diseases (CIBERER, Valencia, Spain; 4Catholic University San Vicente Martir, Valencia, Spain; 5Department of Genetics, La Fe University Hospital of Valencia, Valencia, Spain; 6Clinica Oftalmologica Centro Caracas, Retina and VItreous Service, Caracas, DC, VenezuelaPurpose: To evaluate the efficacy and safety of the pars plana clip (PPC in the Ahmed valve tube inserted via the pars plana in patients with secondary refractory glaucomas.Methods: Prospective and interventional case series that included 10 patients with secondary refractory glaucoma. The pars plana vitrectomy and the implant of the modified tube were performed during the same surgery. Control of intraocular pressure (IOP and the development of intra- and postoperative complications were evaluated during the follow-up.Results: Follow-up time was twelve months in all the patients. Control of IOP was achieved in 90% of patients, and 70% needed no antiglaucoma treatment. The complications that occurred were transient hypotony in three cases, choroidal detachment in two cases, and one case of intraocular hemorrhage. No case of tube extrusion or tube kink was observed.Conclusions: Our data suggests that implantation of the Ahmed tube modified with the PPC via the pars plana is safe and effective in patients with secondary refractory glaucomas. Keywords: pars plana clip, Ahmed valve, refractory glaucoma, pars plana vitrectomy

  12. Dynamic tube movement after reimplantation of Ahmed glaucoma valve in a child with glaucoma in aphakia

    Science.gov (United States)

    Senthil, Sirisha; Badakare, Akshay

    2014-01-01

    A 10-year-old girl underwent an Ahmed glaucoma valve (AGV) implantation as a primary procedure for glaucoma in aphakia due to congenital cataract surgery. Following an unintended accidental excision of AGV tube during bleb revision for hypertensive phase, AGV was explanted and a second AGV was implanted in the same quadrant after 2 weeks. This resulted in a rare complication of dynamic tube movement in the anterior chamber with tube corneal touch and localised corneal oedema. Excision of the offending unstable tube and placement of a paediatric AGV in a different quadrant led to resolution of this complication, stable vision and well-controlled intraocular pressure. This case highlights the possible causes of dynamic tube, related complications and its management. This case also highlights the importance of understanding the various physiological phases after glaucoma drainage device implantation and their appropriate management. PMID:24695662

  13. Efficacy of long scleral tunnel technique in preventing Ahmed glaucoma valve tube exposure through conjunctiva.

    Science.gov (United States)

    Kugu, Suleyman; Erdogan, Gurkan; Sevim, M Sahin; Ozerturk, Yusuf

    2015-01-01

    To evaluate the efficacy of long scleral tunnel technique used in Ahmed glaucoma valve (AGV) implantation in preventing tube exposure through conjunctiva. Patients of adult age, who were unresponsive to maximum medical treatment and underwent AGV implantation, were divided into two groups and investigated retrospectively. Group 1 consisted of 40 eyes of 38 patients that underwent surgery by long scleral tunnel technique and Group 2 consisted of 38 eyes of 35 patients that underwent implantation by processed pericardium patch graft method. The mean age was 54.8 ± 14.6 years (range 26-68 years) and the mean follow-up duration was 46.7 ± 19.4 months (range 18-76 months) for the patients in Group 1, whereas the mean age was 58.6 ± 16.7 years (range 32-74 years) and mean follow-up period was 43.6 ± 15.7 months (range 20-72 months) for the patients in Group 2 (p > 0.05). In the course of follow-up, tube exposure was detected in one (2.5%) eye in Group 1 and in three (7.9%) eyes in Group 2 (p = 0.042). Long scleral tunnel technique is beneficial in preventing conjunctival tube exposure in AGV implantation surgery.

  14. Outcomes and Complications of Scleral-Fixated Intraocular Lens Combined with Ahmed Tube Surgery

    Directory of Open Access Journals (Sweden)

    Nikhel Sachdev

    2018-01-01

    Full Text Available Background. To evaluate the outcome and complications of transscleral suture-fixated posterior chamber intraocular lens (PCIOL implantation combined with Ahmed glaucoma valve (AGV surgery in Asian eyes. Design. This was a retrospective study that included 22 eyes from 22 participants. The surgeries were performed at Singapore’s National University Hospital. Participants underwent an Ahmed tube surgery, together with transscleral suture-fixated posterior chamber intraocular lens. Main Outcome Measures. Complete success was defined as 6 ≤ intraocular pressure (IOP ≤ 21 mmHg without medications at the last follow-up visit, with no reoperation required and no progression to no perception of light (NPL. Results. At the last follow-up, there was a significant reduction in mean IOP (22.4 ± 6.5 mmHg versus 13.9 ± 3.9 mmHg; p<0.001 and mean number of intraocular pressure-lowering medications (2.45 ± 1.30 versus 0.05 ± 0.21; p<0.001. There was no significant change in visual acuity [1.43 ± 1.21 (LogMAR versus 1.09 ± 1.31 (p=0.204]. Sixteen eyes (72.7% achieved complete success. The 3 commonest complications were bullous keratopathy, choroidal detachment, and displacement of intraocular lens. Conclusion and Relevance. This technique showed good success for intraocular pressure control and vision preservation. Postoperative complications were relatively common although most were self-limiting. Patients at increased risk of trabeculectomy failure may be suitable for this procedure.

  15. Tension Pneumothorax and Subcutaneous Emphysema Complicating Insertion of Nasogastric Tube

    Directory of Open Access Journals (Sweden)

    Narjis AL Saif

    2015-01-01

    Full Text Available Nasogastric tube has a key role in the management of substantial number of hospitalized patients particularly the critically ill. In spite of the apparent simple insertion technique, nasogastric tube placement has its serious perhaps fatal complications which need to be carefully assessed. Pulmonary misplacement and associated complications are commonplace during nasogastric tube procedure. We present a case of tension pneumothorax and massive surgical emphysema in critically ill ventilated patient due to inadvertent nasogastric tube insertion and also discussed the risk factors, complication list, and arrays of techniques for safer tube placement.

  16. Blind bedside insertion of small bowel feeding tubes.

    LENUS (Irish Health Repository)

    Duggan, SN

    2009-12-01

    The use of Naso-Jejunal (NJ) feeding is limited by difficulty in feeding tube placement. Patients have traditionally required transfer to Endoscopy or Radiology for insertion of small bowel feeding tubes, with clear resource implications. We hypothesised that the adoption of a simple bedside procedure would be effective and reduce cost. Clinical nutrition and nurse specialist personnel were trained in the 10\\/10\\/10 method of blind bedside NJ insertion.

  17. Tenon advancement and duplication technique to prevent postoperative Ahmed valve tube exposure in patients with refractory glaucoma.

    Science.gov (United States)

    Tamcelik, Nevbahar; Ozkok, Ahmet; Sarıcı, Ahmet Murat; Atalay, Eray; Yetik, Huseyin; Gungor, Kivanc

    2013-07-01

    To present and compare the long-term results of Dr. Tamcelik's previously described technique of Tenon advancement and duplication with the conventional Ahmed glaucoma valve (AGV) implantation technique in patients with refractory glaucoma. This study was a multicenter, retrospective case series that included 303 eyes of 276 patients with refractory glaucoma who underwent glaucoma valve implantation surgery. The patients were divided into three groups according to the surgical technique applied and the outcomes compared. In group 1, 96 eyes of 86 patients underwent AGV implant surgery without patch graft; in group 2, 78 eyes of 72 patients underwent AGV implant surgery with donor scleral patch; in group 3, 129 eyes of 118 patients underwent Ahmed valve implant surgery with "combined short scleral tunnel with Tenon advancement and duplication technique". The endpoint assessed was tube exposure through the conjunctiva. In group 1, conjunctival tube exposure was seen in 11 eyes (12.9 %) after a mean 9.2 ± 3.7 years of follow-up. In group 2, conjunctival tube exposure was seen in six eyes (2.2 %) after a mean 8.9 ± 3.3 years of follow-up. In group 3, there was no conjunctival exposure after a mean 7.8 ± 2.8 years of follow-up. The difference between the groups was statistically significant. (P = 0.0001, Chi-square test). This novel surgical technique combining a short scleral tunnel with Tenon advancement and duplication was found to be effective and safe to prevent conjunctival tube exposure after AGV implantation surgery in patients with refractory glaucoma.

  18. Clinical findings following Ahmed Glaucoma Valve™ implantation in pediatric glaucoma

    Directory of Open Access Journals (Sweden)

    Amir Pirouzian

    2008-03-01

    Full Text Available Amir Pirouzian1, Joseph L Demer21Department of Ophthalmology, San Diego Children’s Hospital, San Diego, UCSD, San Diego, CA, USA; 2Department of Ophthalmology, Jules Stein Eye Institute, UCLA, Los Angeles, CA, USAPurpose: To describe clinical findings after Ahmed valve drainage implantation in children.Design: All records in one practice were reviewed to identify and describe clinical findings in all children who had undergone Ahmed Glaucoma ValveTM S2 model insertion for uncontrolled primary or secondary glaucoma.Results: A total of 6 patients were identified, ranging in age from 2–15 years. Mean follow-up time averaged from 2–5 years from the time of tube insertion. Three patients exhibited pupillary peaking towards the tube of the valve. All patients required additional surgery or additional medications to control intraocular pressure. Lenticular opacification near the tube site developed in one patient. Gradual tube extrusion was also noted in another two patients.Conclusion: Multiple clinical events follow the Ahmed valve insertion in children. Pupillary irregularity is the most commonly noted event in this series. To avoid or reduce the risk of this complication, additional or modification of surgical procedures could be considered. The mechanism of such occurrence will further be discussed.Keywords: Ahmed Glaucoma Valve, children, pediatric glaucoma

  19. Guide tube insert assembly for use in a nuclear reactor

    International Nuclear Information System (INIS)

    Hopkins, R.J.; Land, J.T.

    1992-01-01

    This patent describes an internals assembly for a nuclear reactor of the type including an upper support plate and an upper core plate, each having apertures for conducting control rod assemblies into an out of fuel assemblies with the apertures of the upper support plate being aligned with the apertures of the upper core plate, a guide tube insert assembly comprising: an elongated tubular body extending between at least one of the aligned apertures formed in the upper support plate and the upper core plate; guide plates within the elongated tubular body, each of the guide plates having a planar surface extending substantially perpendicular to an axial direction of the tubular body; at least one interconnecting means for interconnecting the guide plates into a guide tube insert assembly such that the guide plates are simultaneously mountable within and removable from the elongated body, and the periphery of each of the guide plates is spaced apart from the inner walls of the elongated tubular body at every point when the insert assembly is mounted within the tubular body, and a stabilizing means for securing the lowermost guide plate of the guide tube insert assembly within the elongated tubular body to prevent rotational and lateral movement between the guide tube insert assembly and the tubular body

  20. Otological Findings Ten Years after Myringotomy with Tympanostomy Tube Insertion

    Directory of Open Access Journals (Sweden)

    Ali Goljanian Tabrizi

    2011-01-01

    Full Text Available Introduction: To study the long-term complications of tympanostomy tube insertion in young children 10 years after surgery.   Materials and Methods: In September 2011, the medical records of all patients who had undergone myringotomy with tympanostomy tube insertion between February 2000 and March 2001 at the two general hospitals of Isfahan University of Medical Sciences were studied. Of the 98 patients who fulfilled the inclusion criteria, 82 patients agreed to participate and were enrolled in the study. The complications of the operation were evaluated in these patients.   Results: Of the 164 ears that were operated on, myringosclerosis was found in 17.1%, atrophy of the tympanic membrane in 1.2%, permanent perforation of the tympanic membrane in 0.6% and tympanic membrane atelectasis in 0.6%. None of the patients developed cholesteatoma as a complication of tympanostomy tube insertion.   Conclusion:  Considering the low risk of serious complications after 10 years, tympanostomy tube insertion is a safe and effective treatment option in the treatment of otitis media with effusion.

  1. A new surgical technique of intra-scleral tube fixation in Ahmed Glaucoma Valve implantation: ‘Scleral Sleeve Method’

    Directory of Open Access Journals (Sweden)

    Charudutt Kalamkar

    2017-10-01

    Full Text Available Purpose: To present a new surgical technique ‘Scleral Sleeve Method’ which would reduce the risk of Ahmed Glaucoma Valve (AGV tube related complications in patients undergoing AGV FP7 (New World Medical Inc., Rancho Cucamonga, CA for refractory glaucoma. Design: Prospective, Non-Randomized, hospital based interventional case series. Subjects: A total of 16 eyes of adult patients (10 males and 6 females with refractory glaucoma. Methods: Instead of using sutures to fix the AGV tube to sclera, we devised a novel method of intra-scleral tube fixation by creating a scleral tunnel fashioned in form of sleeve. Main outcome measure: Post-operative tube related complications. Result: There were no tube related complications such as exposure, extrusion or retraction in any of the cases. Conclusion: Use of scleral sleeve method for tube fixation, along with graft to cover the tube, will provide additional safety measure and reduce the risks of tube related complications. Keywords: Ahmed Glaucoma Valve, Scleral Sleeve Method, Intra-scleral tube fixation

  2. Heat transfer behaviors in round tube with conical ring inserts

    International Nuclear Information System (INIS)

    Promvonge, P.

    2008-01-01

    To increase convection heat transfer in a uniform heat flux tube by a passive method, several conical rings used as turbulators are mounted over the test tube. The effects of the conical ring turbulator inserts on the heat transfer rate and friction factor are experimentally investigated in the present work. Conical rings with three different diameter ratios of the ring to tube diameter (d/D = 0.5, 0.6, 0.7) are introduced in the tests, and for each ratio, the rings are placed with three different arrangements (converging conical ring, referred to as CR array, diverging conical ring, DR array and converging-diverging conical ring, CDR array). In the experiment, cold air at ambient condition for Reynolds numbers in a range of 6000-26,000 is passed through the uniform heat flux circular tube. It is found that the ring to tube diameter ratio and the ring arrays provide a significant effect on the thermal performance of the test tube. The experimental results demonstrate that the use of conical ring inserts leads to a higher heat transfer rate than that of the plain surface tube, and the DR array yields a better heat transfer than the others. The results are also correlated in the form of Nusselt number as a function of Reynolds number, Prandtl number and diameter ratio. An augmentation of up to 197%, 333%, and 237% in Nusselt number is obtained in the turbulent flow for the CR, DR and CDR arrays, respectively, although the effect of using the conical ring causes a substantial increase in friction factor

  3. Factors related to persisting perforations after ventilation tube insertion.

    Science.gov (United States)

    O'Connell Ferster, Ashley P; Tanner, April Michelle; Karikari, Kodjo; Roberts, Christopher; Wiltz, Derek; Carr, Michele M

    2016-02-01

    Over a million ventilation tubes are placed annually in the United States, making this one of the most commonly performed procedures in the field of medicine. Certain factors increase the risk of persistent tympanic membrane perforation following the extrusion of short term ventilation tubes. Persistent perforations may fail to heal on their own, necessitating surgical closure to avoid conductive hearing loss. It is important to detect factors that may predict children who are at increased risk for persistent perforations. This study was a retrospective chart review that involved 757 patients between 2003 and 2008. The patients studied were within the age of 2 months-17 years, and all had short term tubes placed. The chart data also included demographic information, comorbidities, and information related to tube insertion and follow-up care. Chi-square, t-test, and multivariate logistic regression were conducted to compare variables between patients with perforations and those without. Data from 757 patients was analyzed, showing that perforation rate is associated with rhinorrhea, operative tube removal, aural polyps, and otorrhea (OR 1.72, 8.16, 4.69, and 1.72 respectively). The absence of otorrhea decreased the likelihood of TM perforations and no significant differences were found in gender, total number of sets of tubes, type of tube, use of nasal steroids, adenoidectomy, or nasal congestion. Our findings suggest that children with rhinorrhea, otorrhea, aural polyps, or prolonged intubation requiring operative tube removal should be identified clinically as children at risk of persisting perforation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Asma Ahmed

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Asma Ahmed. Articles written in Resonance – Journal of Science Education. Volume 14 Issue 5 May 2009 pp 455-471 General Article. The Major Players in Adaptive Immunity - Humoral Immunity · Asma Ahmed Banishree Saha Anand Patwardhan Shwetha ...

  5. Research on temperature control and influence of the vacuum tubes with inserted tubes solar heater

    Science.gov (United States)

    Xiao, L. X.; He, Y. T.; Hua, J. Q.

    2017-11-01

    A novel snake-shape vacuum tube with inserted tubes solar collector is designed in this paper, the heat transfer characteristics of the collector are analyzed according to its structural characteristics, and the influence of different working temperature on thermal characteristics of the collector is studied. The solar water heater prototype consisting of 14 vacuum tubes with inserted tubes is prepared, and the hot water storage control subsystem is designed by hysteresis comparison algorithm. The heat characteristic of the prototype was experimentally studied under hot water output temperature of 40-45°C, 50-55°C and 60-65°C. The daily thermal efficiency was 64%, 50% and 46%, respectively. The experimental results are basically consistent with the theoretical analysis.

  6. Intracameral air injection during Ahmed glaucoma valve implantation in neovascular glaucoma for the prevention of tube obstruction with blood clot: Case Report.

    Science.gov (United States)

    Hwang, Sung Ha; Yoo, Chungkwon; Kim, Yong Yeon; Lee, Dae Young; Nam, Dong Heun; Lee, Jong Yeon

    2017-12-01

    Glaucoma drainage implant surgery is a treatment option for the management of neovascular glaucoma. However, tube obstruction by blood clot after Ahmed glaucoma valve (AGV) implantation is an unpredictable clinically challenging situation. We report 4 cases using intracameral air injection for the prevention of the tube obstruction of AGV by blood clot. The first case was a 57-year-old female suffering from ocular pain because of a tube obstruction with blood clot after AGV implantation in neovascular glaucoma. Surgical blood clot removal was performed. However, intractable bleeding was noted during the removal of the blood clot, and so intracameral air injection was performed to prevent a recurrent tube obstruction. After the procedure, although blood clots formed around the tube, the tube opening where air could touch remained patent. In 3 cases of neovascular glaucoma with preoperative severe intraocular hemorrhages, intracameral air injection and AGV implantation were performed simultaneously. In all 3 cases, tube openings were patent. It appears that air impeded the blood clots formation in front of the tube opening. Intracameral air injection could be a feasible option to prevent tube obstruction of AGV implant with a blood clot in neovascular glaucoma with high risk of tube obstruction. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  7. A Novel Surgical Technique for Ahmed Valves in Refractory Glaucoma With Silicone Oil Endotamponade.

    Science.gov (United States)

    Davo-Cabrera, Juan Maria; Lanzagorta-Aresti, Aitor; Alcocer Yuste, Pablo

    2017-10-01

    The purpose of the study is to describe a novel technique to implant Ahmed valves in patients with refractory glaucoma because of silicone oil (SO) endotamponade PATIENTS:: Three patients with glaucoma without SO removal were used as an example for this technique. Technique report. We introduce a standard technique modification for Ahmed valves in patients with SO. This modification consists on locating the Ahmed valve more tangential to the limbus curvature instead of the usual perpendicular position and inserting the tube in the posterior chamber. The tube can be longer and run parallel to pupil. This technique allows use superotemporal quadrant (fewer complications), avoid corneal touch and decrease SO loss through the tube to subconjunctival space.

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

    Science.gov (United States)

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

    2016-01-01

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

  9. Current microbiology of percutaneous endoscopic gastrostomy tube (PEG tube) insertion site infections in patients with cancer.

    Science.gov (United States)

    Rolston, Kenneth V I; Mihu, Coralia; Tarrand, Jeffrey J

    2011-08-01

    Percutaneous endoscopic gastrostomy (PEG) is frequently used to provide enteral access in cancer patients who are unable to swallow. Infection is an important complication in this setting. Current microbiological data are needed to guide infection prevention and treatment strategies. The microbiological records of our institution (a 550-bed comprehensive cancer center) were retrospectively reviewed over an 8-month study period in order to identify patients who developed PEG tube insertion site infections, and review their microbiological details and susceptibility/resistance data. Fifty-eight episodes of PEG tube insertion site infections were identified. Of these, 31 (53%) were monomicrobial, and the rest were polymicrobial. The most common organisms isolated were Candida species, Staphylococcus aureus, and Pseudomonas aeruginosa. All infections were local (cellulitis, complicated skin, and skin structure infections including abdominal wall abscess) with no cases of concomitant bacteremia being documented. Most of the organisms isolated were susceptible to commonly used antimicrobial agents, although some quinolone-resistant and some multidrug-resistant organisms were isolated. This retrospective study provides descriptive data regarding PEG tube insertion site infections. These data have helped us update institutional guidelines for infection prevention and treatment as part of our focus on antimicrobial stewardship.

  10. A Novel Device for Accurate Chest Tube Insertion

    DEFF Research Database (Denmark)

    Katballe, Niels; Moeller, Lars B; Olesen, Winnie H

    2016-01-01

    BACKGROUND: Optimal positioning of a large-bore chest tube is in the part of the pleural cavity that needs drainage. It is recommended that the chest tube be positioned apically in pneumothorax and basally for fluids. However, targeted chest tube positioning to a specific part of the pleural cavity...... can be a challenge. METHODS: A new medical device, the KatGuide, was developed for accurate guiding of a chest tube (28F) to an intended part of the pleural cavity. The primary end point of this randomized, controlled trial was optimal position of the chest tube. The optimal position in pneumothorax...

  11. [Long-term follow-up after tympanostomy tube insertion in children with serous otitis media].

    Science.gov (United States)

    Fekete-Szabó, Gabriella; Kiss, Fekete; Rovó, László

    2015-11-15

    The authors report about the efficacy of inserted tympanostomy tube in children with serous otitis media. The aim of the authors was to assess the status of eardrum, the function of Eustachian tube and hearing level 10 years after the use of tympanostomy tube. Patients filled out a questionnaire and microscopic examination of tympanic membrane, tympanometry, Eustachian tube function examination, and audiometry tests were performed. In the period of 2003-2004, ventilation tube insertion was performed in 711 patients in the ENT Department of Pediatric Health Center of University of Szeged. In 349 patients adenotomy and tympanostomy tube insertion, in 18 cases tonsillectomy and grommet insertion and in 344 patients only typmanostomy tube insertion were performed. Due to objective difficulties (address change, no phone number) 453 patients were asked for control test and 312 persons accepted the invitation. Normal hearing level was found in 84.6% of patients and normal tympanometry result occurred in 82%. Tympanic ventilation disorder, perforation of tympanic membrane, sensorineural hearing loss and sensorineural hearing loss due to noise exposure were diagnosed. Application of tympanostomy tube is effective in the treatment of serous otitis media resulting from ventilation disorder. The authors draw attention to the importance of tympanometry examination to prevent the adhesive processes and cholesteatoma in chronic ventilation disorder of the middle ear.

  12. Thermohydraulic performance comparision of compound inserts for a turbulent flow through a circular tube

    Directory of Open Access Journals (Sweden)

    Kapse Arvind A.

    2017-01-01

    Full Text Available Heat transfer and pressure drop characteristics of three different passive inserts are experimentally investigated for individual and compound insertion. Insert cross-section is altered along the length of test section for compound insertion. Test runs were conducted in a concentric circular tube in tube heat exchanger in the Reynolds number range of 8000 to 32000 with water as a working fluid. Enhancements in Nusselt number and friction factors are reported to be in the range of 38-234% and 55-524%, respectively, over plain tube. The average performance ratios based on equal pumping power are also reported and found in the range of 0.63-1.53. Based on experimental results, optimum combination for compound insertion is proposed.

  13. How do You Select an Anesthesia Method Prior to Tympanostomy Tube Insertion for a Child?

    OpenAIRE

    Lee, Dong-Hee

    2016-01-01

    The use of general (face-mask inhalation and intravenous) anesthesia has been the method of choice for tympanostomy tube insertion in children. However, there is no exact guideline for the choice of anesthesia method and there is no evidence to support the use of one anesthesia method over another. Clinically, the anesthesia method used to be decided by old customs and the surgeon's blind faith that children cannot bear tympanostomy tube insertion under local anesthesia. Clinicians should kee...

  14. Alternative method for predicting optimal insertion depth of the laryngeal tube in children.

    Science.gov (United States)

    Kim, J T; Jeon, S Y; Kim, C S; Kim, S D; Kim, H S

    2007-11-01

    Little information is available about the accuracy of the teeth mark on the laryngeal tube (LT) as a guide to correct placement in children. The aim of this crossover study was to evaluate three methods for optimal insertion depth of the size (#) 2 tube in children weighing 12-25 kg. In 24 children, the LT #2 was consecutively inserted by three different methods: (A) until the thick teeth mark on the tube was aligned with the upper incisors, (B) until resistance was felt, and (C) by inserting to a depth, previously measured, of the curved distance between the cricoid cartilage and the upper incisor. In each case, the depth of insertion, the degree of effective ventilation, the presence of leakage, and the fibreoptic view were assessed. Insertion based on the teeth mark led to a shorter insertion depth and a greater incidence of inadequate ventilation compared with the other two methods. There was no difference in the adequacy of ventilation between methods B and C. The vocal cords were more easily identified with methods B (62.5%) and C (75%) than with method A (12.5%). Insertion of the LT #2 aligned with the teeth mark can result in a shallow insertion depth and inadequate ventilation. The measured distance from the cricoid cartilage to the upper incisor offers alternative guidance for correct LT insertion.

  15. Repairing a steam generator tube by inserting a sheath

    International Nuclear Information System (INIS)

    Gaudin, J.P.

    1986-01-01

    According to the invention, the mechanical deformation of the sheath, realized by expansion in its end part opposite to the expanded end within the tube plate, is situated along a limited height, and the parameters of the said mechanical deformation are calculated according to the welding parameters applied consecutively. Besides, the said welding parameters are determined according to the initial mechanical deformation to obtain stress relaxation more particularly in the singular zones of the mechanical deformation. The present invention applies to the repair of PWR steam generator tubes [fr

  16. Propionibacterium acnes endophthalmitis in Ahmed glaucoma valve.

    Science.gov (United States)

    Gutiérrez-Díaz, E; Montero-Rodríguez, M; Mencía-Gutiérrez, E; Fernández-González, M C; Pérez-Blázquez, E

    2001-01-01

    To report a case of Propionibacterium acnes endophthalmitis in a patient with an Ahmed glaucoma valve. A nine-year-old boy with bilateral congenital glaucoma, with an Ahmed glaucoma valve implanted in the left eye, had recurrent conjunctival dehiscence and endophthalmitis. Vitreous cultures demonstrated the presence of Propionibacterium acnes. This is the first reported case of Propionibacterium acnes endophthalmitis in an Ahmed glaucoma valve and the second one in a glaucoma drainage device. We strongly recommend using a patch graft to prevent and treat tube exposure. Conjunctival grafts may be useful to close the conjunctiva when there is marked scarring to prevent patch exposure and melting or extrusion.

  17. A novel method for improving chest tube insertion skills among medical interns

    Science.gov (United States)

    Tatli, Ozgur; Turkmen, Suha; Imamoglu, Melih; Karaca, Yunus; Cicek, Mustafa; Yadigaroglu, Metin; Bayrak, Selen T.; Asik, Olgun; Topbas, Murat; Turedi, Suleyman

    2017-01-01

    Objectives: To develop a low-cost biomaterial-covered chest tube simulation model and assess its possible usefulness for developing the chest tube insertion skills among medical interns. Methods: This mannequin-based interventional study was performed in a University hospital setting. We included 63 physicians performing emergency medicine internship at the Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey, between January 2015 and March 2015. A dummy was prepared for training simulation using a display mannequin. Medical interns received instruction concerning pneumothorax and the chest tube procedure. A total of 63 medical interns participating in this interventional study were asked to insert a chest tube in a biomaterial-covered mannequin. A senior trainee scored their performance using a check list and the mean of the total scores was calculated (21 items; total score, 42). Results: The mean procedural score was 40.9 ± 1.3 of a possible 42. The maximum score of 42 was achieved by 39.7% of the medical interns, while another 33.3% achieved a score of 41. Of the participants, 85% succeeded in inserting the tube via an appropriate technique, achieving a score of 40 or more. Conclusion: Our results indicated that this model could be useful for effective training of medical interns for chest tube insertion, which is an important skill in emergency medicine. This biomaterial-covered model is inexpensive and its use can potentially be widened to improve training methods without significant financial demand. PMID:28917064

  18. Swirl flow analysis in a helical wire inserted tube using CFD code

    International Nuclear Information System (INIS)

    Park, Yusun; Chang, Soon Heung

    2010-01-01

    An analysis on the two-phase flow in a helical wire inserted tube using commercial CFD code, CFX11.0, was performed in bubbly flow and annular flow regions. The analysis method was validated with the experimental results of Takeshima. Bubbly and annular flows in a 10 mm inner diameter tube with varying pitch lengths and inserted wire diameters were simulated using the same analysis methods after validation. The geometry range of p/D was 1-4 and e/D was 0.08-0.12. The results show that the inserted wire with a larger diameter increased swirl flow generation. An increasing swirl flow was seen as the pitch length increased. Regarding pressure loss, smaller pitch lengths and inserted wires with larger diameters resulted in larger pressure loss. The average liquid film thickness increased as the pitch length and the diameter of the inserted wire increased in the annular flow region. Both in the bubbly flow and annular flow regions, the effect of pitch length on swirl flow generation and pressure loss was more significant than that of the inserted wire diameters. Pitch length is a more dominant factor than inserted wire diameter for the design of the swirl flow generator in small diameter tubes.

  19. Development of a nasogastric tube insertion simulator: a collaborative interdisciplinary effort.

    Science.gov (United States)

    Summer, Lindsay; Gonzalez, Laura; Jimeno, Miguel; Christensen, Ken

    2009-01-01

    The nursing faculty shortage has created the need for more innovative and effective ways to better stimulate nursing students. Simulation technology is one way to increase the effectiveness of teaching faculty. In this article, a collaborative project between the College of Nursing and College of Engineering at the University of South Florida to develop and evaluate a PC-based software simulator based on videogame technologies for nursing skill acquisition is discussed. A software simulator for teaching and assessing mastery of the procedure for nasogastric tube insertion is described. The purpose of the simulator is to complement the standard training of nasogastric tube insertion that uses static mannequins and instruction/assessment by nursing instructors. The simulator was used in a fundamentals of nursing class at the University of South Florida, with 75 students enrolled. Evaluation showed that the simulator significantly increased the confidence of the students in their ability to perform nasogastric tube insertion.

  20. Reusable locking tube insertion and removal fixture and method in a reconstitutable fuel assembly

    International Nuclear Information System (INIS)

    Shallenberger, J.M.; Ferlan, S.J.

    1987-01-01

    This patent describes a locking tube insertion and removal fixture for use with a reconstitutable fuel assembly. The process includes a top nozzle with an adapter plate having at least one passageway, at least one guide thimble with an upper end portion, and an attaching structure having a hollow locking tube insertable and removable into and from a locking position in the upper end portion of the guide thimble for releasably locking the upper end portion of the guide thimble within the passageway of the top nozzle and adapter plate

  1. Disc-retained tubes for radiologically inserted gastrostomy (RIG): Not up to the job?

    International Nuclear Information System (INIS)

    Kibriya, N.; Wilbraham, L.; Mullan, D.; Puro, P.; Vasileuskaya, S.; Edwards, D.W.; Laasch, H.-U.

    2013-01-01

    Aim: To assess the insertion procedure and performance of disc-retained gastrostomy tubes, recording complications and accidental displacements by prospective audit, and to determine whether primary placement of the tube off-licence was feasible. Materials and methods: Disc-retained 12 F single-lumen Monarch gastrostomy tubes (Enteral UK, Selby, UK) were inserted by three gastrointestinal interventional radiologists in a supra-regional cancer centre. The 12 F tubes required a 20 F peel-away sheath with four-point gastropexy fixation and were placed under conscious sedation, using electrocardiogram (EEG) bispectral index monitoring. Follow-up was performed in an in-house gastrostomy drop-in clinic at 1 week and 1 month, supplemented with weekly telephone follow-up. Patients also had open access to the gastrostomy drop-in clinic for immediate advice and complication management. Results: Eighteen patients underwent primary insertion of a Monarch gastrostomy tube over 5 months. A total of 6/18 (33%) tubes displaced; 4/18 (22%) completely, 2/18 (11%) occult into the peritoneum. Four of 18 (22%) patients developed infection at the stoma site. Due to the unexpectedly poor performance of the tube, the study was terminated early. Conclusion: Initial experience with the Monarch disc-retained gastrostomy tube demonstrates it unsuitable for primary placement with current protocols. In view of the potentially serious complications, the Medicines and Healthcare Products Regulatory Agency (MHRA) has been informed. A request has been made to the distributer to reassess the tube design and/or review the procedure promoted for primary placement

  2. Peritonitis following percutaneous gastrostomy tube insertions in children

    International Nuclear Information System (INIS)

    Dookhoo, Leema; Mahant, Sanjay; Parra, Dimitri A.; John, Philip R.; Amaral, Joao G.; Connolly, Bairbre L.

    2016-01-01

    Percutaneous retrograde gastrostomy has a high success rate, low morbidity, and can be performed under different levels of sedation or local anesthesia in children. Despite its favourable safety profile, major complications can occur. Few studies have examined peritonitis following percutaneous retrograde gastrostomy in children. To identify potential risk factors and variables influencing the development and early diagnosis of peritonitis following percutaneous retrograde gastrostomy. We conducted a retrospective case-control study of children who developed peritonitis within 7 days of percutaneous retrograde gastrostomy between 2003 and 2012. From the 1,504 patients who underwent percutaneous retrograde gastrostomy, patients who developed peritonitis (group 1) were matched by closest date of procedure to those without peritonitis (group 2). Peritonitis was defined according to recognized clinical criteria. Demographic, clinical, procedural, management and outcomes data were collected. Thirty-eight of 1,504 children (2.5%; 95% confidence interval, 1.8-3.5) who underwent percutaneous retrograde gastrostomy developed peritonitis ≤7 days post procedure (group 1). Fever (89%), irritability (63%) and abdominal pain (55%) occurred on presentation of peritonitis. Group 1 patients were all treated with antibiotics; 41% underwent additional interventions: tube readjustments (8%), aspiration of pneumoperitoneum (23%), laparotomy (10%) and intensive care unit admission (10%). In group 1, enteral feeds started on average 3 days later and patients were discharged 5 days later than patients in group 2. There were two deaths not directly related to peritonitis. Neither age, gender, weight, underlying diagnoses nor operator was identified as a risk factor. Peritonitis following percutaneous retrograde gastrostomy in children occurs in approximately 2.5% of cases. No risk factors for its development were identified. Medical management is usually sufficient for a good outcome

  3. Peritonitis following percutaneous gastrostomy tube insertions in children.

    Science.gov (United States)

    Dookhoo, Leema; Mahant, Sanjay; Parra, Dimitri A; John, Philip R; Amaral, Joao G; Connolly, Bairbre L

    2016-09-01

    Percutaneous retrograde gastrostomy has a high success rate, low morbidity, and can be performed under different levels of sedation or local anesthesia in children. Despite its favourable safety profile, major complications can occur. Few studies have examined peritonitis following percutaneous retrograde gastrostomy in children. To identify potential risk factors and variables influencing the development and early diagnosis of peritonitis following percutaneous retrograde gastrostomy. We conducted a retrospective case-control study of children who developed peritonitis within 7 days of percutaneous retrograde gastrostomy between 2003 and 2012. From the 1,504 patients who underwent percutaneous retrograde gastrostomy, patients who developed peritonitis (group 1) were matched by closest date of procedure to those without peritonitis (group 2). Peritonitis was defined according to recognized clinical criteria. Demographic, clinical, procedural, management and outcomes data were collected. Thirty-eight of 1,504 children (2.5%; 95% confidence interval, 1.8-3.5) who underwent percutaneous retrograde gastrostomy developed peritonitis ≤7 days post procedure (group 1). Fever (89%), irritability (63%) and abdominal pain (55%) occurred on presentation of peritonitis. Group 1 patients were all treated with antibiotics; 41% underwent additional interventions: tube readjustments (8%), aspiration of pneumoperitoneum (23%), laparotomy (10%) and intensive care unit admission (10%). In group 1, enteral feeds started on average 3 days later and patients were discharged 5 days later than patients in group 2. There were two deaths not directly related to peritonitis. Neither age, gender, weight, underlying diagnoses nor operator was identified as a risk factor. Peritonitis following percutaneous retrograde gastrostomy in children occurs in approximately 2.5% of cases. No risk factors for its development were identified. Medical management is usually sufficient for a good outcome

  4. Peritonitis following percutaneous gastrostomy tube insertions in children

    Energy Technology Data Exchange (ETDEWEB)

    Dookhoo, Leema [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada); University of Toronto, Faculty of Medicine, Toronto, ON (Canada); Mahant, Sanjay [The Hospital for Sick Children, Department of Pediatrics, Toronto, ON (Canada); Parra, Dimitri A.; John, Philip R.; Amaral, Joao G.; Connolly, Bairbre L. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada)

    2016-09-15

    Percutaneous retrograde gastrostomy has a high success rate, low morbidity, and can be performed under different levels of sedation or local anesthesia in children. Despite its favourable safety profile, major complications can occur. Few studies have examined peritonitis following percutaneous retrograde gastrostomy in children. To identify potential risk factors and variables influencing the development and early diagnosis of peritonitis following percutaneous retrograde gastrostomy. We conducted a retrospective case-control study of children who developed peritonitis within 7 days of percutaneous retrograde gastrostomy between 2003 and 2012. From the 1,504 patients who underwent percutaneous retrograde gastrostomy, patients who developed peritonitis (group 1) were matched by closest date of procedure to those without peritonitis (group 2). Peritonitis was defined according to recognized clinical criteria. Demographic, clinical, procedural, management and outcomes data were collected. Thirty-eight of 1,504 children (2.5%; 95% confidence interval, 1.8-3.5) who underwent percutaneous retrograde gastrostomy developed peritonitis ≤7 days post procedure (group 1). Fever (89%), irritability (63%) and abdominal pain (55%) occurred on presentation of peritonitis. Group 1 patients were all treated with antibiotics; 41% underwent additional interventions: tube readjustments (8%), aspiration of pneumoperitoneum (23%), laparotomy (10%) and intensive care unit admission (10%). In group 1, enteral feeds started on average 3 days later and patients were discharged 5 days later than patients in group 2. There were two deaths not directly related to peritonitis. Neither age, gender, weight, underlying diagnoses nor operator was identified as a risk factor. Peritonitis following percutaneous retrograde gastrostomy in children occurs in approximately 2.5% of cases. No risk factors for its development were identified. Medical management is usually sufficient for a good outcome

  5. Conservative use of chest-tube insertion in children with pleural effusion.

    Science.gov (United States)

    Epaud, R; Aubertin, G; Larroquet, M; Pointe, H Ducou-le; Helardot, P; Clement, A; Fauroux, B

    2006-04-01

    The aim of this work was to evaluate the effect of a more conservative use of chest-tube insertion on the short-term and long-term outcome of pleural infection. Sixty-five patients with pleural infection, aged 1 month to 16 years were each treated according to one of the two protocols: classical management with chest-tube insertion (classical group, n = 33), or conservative use of chest-tube insertion (conservative group, n = 32), with drainage indicated only in the case of voluminous pleural effusion defined by a mediastinal shift and respiratory distress and/or an uncontrolled septic situation. The two groups were comparable with regard to age, baseline C-reactive protein (CRP) value and white blood cell counts, pleural thickness, identified bacteria, and antibiotic treatment. Chest-tube insertion was performed in 17 patients (52%) of the classical group compared to eight patients (25%) of the conservative group (P = 0.03). Duration of temperature above 39 degrees C was shorter in the conservative group (10 +/- 1 vs. 14 +/- 1 days, P = 0.01), as was the normalization of CRP (13 +/- 1 vs. 17 +/- 1 days, P = 0.03). Duration of hospitalization and intravenous (IV) antibiotherapy as well as the delay of chest-radiograph normalization was not significantly different between the two groups. A more conservative use of chest-tube insertion did not change short- and long-term outcome of the pleural infection in children. Drainage could be restricted to the most severely affected patients with pleural empyema causing a mediastinal shift and respiratory distress and/or presenting with an uncontrolled septic situation.

  6. [Late endophthalmitis following Ahmed valve].

    Science.gov (United States)

    del-Hierro-Zarzuelo, A; Vico-Ruiz, E; Martínez-de-la-Casa, J M; García-Feijoó, J; Castillo-Martín, A; García-Sánchez, J

    2005-11-01

    A 71-year-old woman with a history of aphakic glaucoma underwent implantation of an Ahmed valve and scleral grafting in her right eye. Postoperative visual acuity was 0.5 and intraocular pressure was 12 mmHg during treatment with brimonidine tartrate (0.2%). Nine months after implantation she suffered a conjunctival infection which was treated with hygienic measures and topical antibiotic therapy. Four days later, she developed an endophthalmitis which was treated with topical, intravitreous and intravenous vancomycin and ceftazidime. The Ahmed drainage implant was replaced at 72 hours. Laboratory culture yielded Haemophilus influenzae. Four days later, the eye was enucleated. Endophthalmitis is an uncommon complication of glaucoma drainage implant surgery. Exposure of the drainage tube represents the greatest risk factor for this condition. Removal of the implant in the first 24 hours is recommended if a good visual prognosis is to be achieved.

  7. Flow pattern assessment in tubes with wire coil inserts in laminar and transition regimes

    International Nuclear Information System (INIS)

    Garcia, A.; Solano, J.P.; Vicente, P.G.; Viedma, A.

    2007-01-01

    The paper presents an analysis of the flow mechanisms in tubes with wire coils using hydrogen bubble visualization and PIV techniques. Results have been contrasted with experimental data on pressure drop. The relation between the observed flow patterns and the friction factor has been analysed. The experimental analysis that has been carried out allows one to state that at low Reynolds numbers (Re < 400) the flow in tubes with wire coils is basically similar to the flow in smooth tubes. At Reynolds numbers between 500 and 700 and in short pitch wire coils a recirculating flow appears. The insertion of wires coils in a smooth tube accelerates significantly the transition to turbulence. This is produced at Reynolds numbers between 700 and 1000 depending on the wire pitch

  8. Heat Transfer Enhancement Studies in a Circular Tube Fitted with Right-Left Helical Inserts with Spacer

    OpenAIRE

    P. K. Nagarajan; P. Sivashanmugam

    2011-01-01

    Experimental investigation of heat transfer and friction factor characteristics of circular tube fitted with 300 right-left helical screw inserts with 100 mm spacer of different twist ratio has been presented for laminar and turbulent flow.. The experimental data obtained were compared with those obtained from plain tube published data. The heat transfer coefficient enhancement for 300 RL inserts with 100 mm spacer is quite comparable with for 300 R-L inserts. Performance evalu...

  9. Comparison of four techniques of nasogastric tube insertion in anaesthetised, intubated patients: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Mohan Chandra Mandal

    2014-01-01

    Full Text Available Background and Aims: Insertion of nasogastric tubes (NGTs in anaesthetised, intubated patients with a conventional method is sometimes difficult. Different techniques of NGT insertion have been tried with varying degree of success. The aim of this prospective, randomised, open-label study was to evaluate three modified techniques of NGT insertion comparing with the conventional method in respect of success rate, time taken for insertion and the adverse events. Methods: In the operation theatre of general surgery, the patients were randomly allocated into four groups: Group C (control group, n = 54, Group W (ureteral guide wire group, n = 54, Group F (neck flexion with lateral pressure, n = 54 and Group R (reverse Sellick′s manoeuvre, n = 54. The number of attempts for successful NGT insertion, time taken for insertion and adverse events were noted. Results: All the three modified techniques were found more successful than the conventional method on the first attempt. The least time taken for insertion was noted in the reverse Sellick′s method. However, on intergroup analysis, neck flexion and reverse Sellick′s methods were comparable but significantly faster than the other two methods with respect to time taken for insertion. Conclusion: Reverse Sellick′s manoeuver, neck flexion with lateral neck pressure and guide wire-assisted techniques are all better alternatives to the conventional method for successful, quick and reliable NGT insertion with permissible adverse events in anaesthetised, intubated adult patients. Further studies after eliminating major limitations of the present study are warranted to establish the superiority of any one of these modified techniques.

  10. Mohammed Farooq Ahmed

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Mohammed Farooq Ahmed. Articles written in Resonance – Journal of Science Education. Volume 3 Issue 3 March 1998 pp 73-75 Book Review. Physical Chemistry · Mohammed Farooq Ahmed · More Details Fulltext PDF ...

  11. Deaths associated with insertion of nasogastric tubes for enteral nutrition in the medical intensive care unit: Clinical and autopsy findings

    Science.gov (United States)

    Smith, Avery L.; Santa Ana, Carol A.; Fordtran, John S.; Guileyardo, Joseph M.

    2018-01-01

    ABSTRACT It is generally assumed that blind insertion of nasogastric tubes for enteral nutrition in patients admitted to medical intensive care units is safe; that is, does not result in life-threatening injury. If death occurs in temporal association with insertion of a nasogastric tube, caregivers typically attribute it to underlying diseases, with little or no consideration of iatrogenic death due to tube insertion. The clinical and autopsy results in three recent cases at Baylor University Medical Center challenge the validity of these notions. PMID:29904295

  12. Cuff depth and continuous chest auscultation method for determination of tracheal tube insertion depth in nasal intubation: observational study.

    Science.gov (United States)

    Ouchi, Kentaro; Sugiyama, Kazuna

    2016-04-01

    Incorrect endobronchial placement of the tracheal tube can lead to serious complications. Hence, it is necessary to determine the accuracy of tracheal tube positioning. Markers are included on tracheal tubes, in the process of their manufacture, as indicators of approximate intubation depth. In addition, continuous chest auscultation has been used for determining the proper position of the tube. We examined insertion depth using the cuff depth and continuous chest auscultation method (CC method), compared with insertion depth determined by the marker method, to assess the accuracy of these methods. After induction of anesthesia, tracheal intubation was performed in each patient. In the CC method, the depth of tube insertion was measured when the cuff had passed through the glottis, and again when breath sounds changed in quality; the depth of tube insertion was determined from these values. In the marker method, the depth of tube insertion was measured and determined when the marker of the tube had reached the glottis, using insertion depth according to the marker as an index. Insertion depth by the marker method was 26.6 ± 1.2 cm and by the CC method was 28.0 ± 1.2 cm (P < 0.0001). The CC method indicated a significantly greater depth than the marker method. This study determined the safe range of tracheal tube placement. Tube positions determined by the CC method were about 1 cm deeper than those determined by the marker. This information is important to prevent accidental one-lung ventilation and accidental extubation. UMIN No. UMIN000011375.

  13. Fluoroscopy-guided insertion of nasojejunal tubes in children - setting local diagnostic reference levels

    International Nuclear Information System (INIS)

    Vitta, Lavanya; Raghavan, Ashok; Sprigg, Alan; Morrell, Rachel

    2009-01-01

    Little is known about the radiation burden from fluoroscopy-guided insertions of nasojejunal tubes (NJTs) in children. There are no recommended or published standards of diagnostic reference levels (DRLs) available. To establish reference dose area product (DAP) levels for the fluoroscopy-guided insertion of nasojejunal tubes as a basis for setting DRLs for children. In addition, we wanted to assess our local practice and determine the success and complication rates associated with this procedure. Children who had NJT insertion procedures were identified retrospectively from the fluoroscopy database. The age of the child at the time of the procedure, DAP, screening time, outcome of the procedure, and any complications were recorded for each procedure. As the radiation dose depends on the size of the child, the children were assigned to three different age groups. The sample size, mean, median and third-quartile DAPs were calculated for each group. The third-quartile values were used to establish the DRLs. Of 186 procedures performed, 172 were successful on the first attempt. These were performed in a total of 43 children with 60% having multiple insertions over time. The third-quartile DAPs were as follows for each age group: 0-12 months, 2.6 cGy cm 2 ; 1-7 years, 2.45 cGy cm 2 ; >8 years, 14.6 cGy cm 2 . High DAP readings were obtained in the 0-12 months (n = 4) and >8 years (n = 2) age groups. No immediate complications were recorded. Fluoroscopy-guided insertion of NJTs is a highly successful procedure in a selected population of children and is associated with a low complication rate. The radiation dose per procedure is relatively low. (orig.)

  14. Radiology responsibilities post NPSA guidelines for nasogastric tube insertion: A single centre review

    International Nuclear Information System (INIS)

    Snaith, Beverly; Flintham, Kevin

    2015-01-01

    Background: There are well-recognised complications associated with malposition of nasogastric (NG) tubes. In 2011 the UK National Patient Safety Agency (NPSA) published an alert regarding their insertion and position confirmation. This alert also identified the expected radiology standards for both image acquisition and reporting. Method: This was a retrospective review of referrals over a six-month period within a multi-site NHS Trust. A consecutive sampling approach was used and radiology reports where the text included the terms “NG tube”, “nasogastric” or “feeding” were included. Data were collected from the radiology information system and NG tube visibility and image quality were confirmed by two independent reviewers. Results: 1137 examinations demonstrated an NG tube, of which 68.3% were performed to check tube position. There was statistically significant correlation between lower radiation exposure and non-visualisation (Fishers exact test, p < 0.001). The number of examinations with higher exposure index (EI) in the NG check cohort suggests that the radiographer increased the exposure to improve visualization (x 2  = 2.846; 95% CI; p = 0.046), although the utility of this is unproven. Malplaced tubes were demonstrated either in the respiratory tract (1.8%) or proximal gastrointestinal tract (8.6%) as a result of insufficient length introduced. Conclusion: The prompt acquisition and reporting of radiographs is essential to reduce the risk of NG tube complications. Respiratory tract misplacement rates were in line with the published literature, but this study does raise concern regarding the number of tubes located in the proximal GI tract. Radiology's responsibility in accurate and effective reporting of medical interventions is significant

  15. A Study on Thermal Performance of a Novel All-Glass Evacuated Tube Solar Collector Manifold Header with an Inserted Tube

    Directory of Open Access Journals (Sweden)

    Jichun Yang

    2015-01-01

    Full Text Available A novel all-glass evacuated tube collector manifold header with an inserted tube is proposed in this paper which makes water in all-glass evacuated solar collector tube be forced circulated to improve the performance of solar collector. And a dynamic numerical model was presented for the novel all-glass evacuated tube collector manifold header water heater system. Also, a test rig was built for model validation and comparison with traditional all-glass evacuated tube collector. The experiment results show that the efficiency of solar water heater with a novel collector manifold header is higher than traditional all-glass evacuated tube collector by about 5% and the heat transfer model of water heater system is valid. Based on the model, the relationship between the average temperature of water tank and inserted tube diameter (water mass flow has been studied. The results show that the optimized diameter of inserted tube is 32 mm for the inner glass with the diameter of 47 mm and the water flow mass should be less than 1.6 Kg/s.

  16. Increasing rate of middle ear ventilation tube insertion in children in denmark

    DEFF Research Database (Denmark)

    Djurhuus, Bjarki Ditlev; Skytthe, Axel; Christensen, Kaare

    2014-01-01

    ventilation tube insertions distributed among 269,459 different children were identified. From 1997 to 2010 the age standardized incidence rate in 0-15-year-olds increased from 26 to 40 per 1000 person years with an estimated annual increase of 2.0% (95% confidence interval 1.9-2.1%). The largest increase...... in incidence rate was found in 1-year-olds with an annual increase of 4.5% (95% confidence interval 4.4-4.6%). Age-specific incidence rates remained at maximum around the age of 14 months throughout the period. The cumulative incidence proportion for the 2010 birth cohort by the time they reach the age of 5......OBJECTIVE: To study the incidence rates of middle ear ventilation tube insertion in children aged 0 to 15 years in Denmark from 1997 to 2010. METHODS: Using two national registers, the Danish National Health Service Register and the Danish National Patient Register, practically all cases of middle...

  17. Oral dextrose for analgesia in neonates during nasogastric tube insertion: a randomised controlled trial.

    Science.gov (United States)

    Ravishankar, Arjun; Thawani, Rajat; Dewan, Pooja; Das, Saurabhi; Kashyap, Archana; Batra, Prerna; Faridi, Moonis Mohammed Akbar

    2014-02-01

    This study aims to determine if oral dextrose solution can mitigate the pain response to nasogastric tube (NGT) insertion in neonates. The study was a double-blinded, placebo-controlled, randomised controlled trial. One hundred and fifty consecutive neonates were randomised into three groups to receive 25% dextrose (D25), or 10% dextrose (D10) or placebo (distilled water). An NGT was inserted after giving 2 mL of one of the solutions orally. Pain response was assessed using the Premature Infant Pain Profile (PIPP), and the duration of cry was noted within 60 s of the intervention. Total PIPP score, duration of cry, change in heart rate and oxygen saturation (SpO2 ) were compared among the three groups. Neonates who received D25 had significantly lesser pain response to NGT insertion in terms of lower PIPP score (P < 0.05) and duration of cry (P = 0.001) compared to D10. There was a significantly smaller increase in heart rate and decrease in SpO2 (P < 0.05). In comparison with placebo, D10 significantly decreased duration of cry (P < 0.05) but not PIPP score. Oral D25 was effective in reducing the pain response during NGT insertion in neonates when compared with oral D10 and placebo. Oral D10 was not found to have a potent analgesic effect for the same. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  18. A novel method for improving chest tube insertion skills among medical interns. Using biomaterial-covered mannequin

    Directory of Open Access Journals (Sweden)

    Ozgur Tatli

    2017-10-01

    Full Text Available Objectives: To develop a low-cost biomaterial-covered chest tube simulation model and assess its possible usefulness for developing the chest tube insertion skills among medical interns. Methods: This mannequin-based interventional study was performed in a University hospital setting. We included 63 physicians performing emergency medicine internship at the Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey, between January 2015 and March 2015. A dummy was prepared for training simulation using a display mannequin. Medical interns received instruction concerning pneumothorax and the chest tube procedure. A total of 63 medical interns participating in this interventional study were asked to insert a chest tube in a biomaterial-covered mannequin. A senior trainee scored their performance using a check list and the mean of the total scores was calculated (21 items; total score, 42. Results: The mean procedural score was 40.9 ± 1.3 of a possible 42. The maximum score of 42 was achieved by 39.7% of the medical interns, while another 33.3% achieved a score of 41. Of the participants, 85% succeeded in inserting the tube via an appropriate technique, achieving a score of 40 or more. Conclusion: Our results indicated that this model could be useful for effective training of medical interns for chest tube insertion, which is an important skill in emergency medicine. This biomaterial-covered model is inexpensive and its use can potentially be widened to improve training methods without significant financial demand.

  19. A novel method for improving chest tube insertion skills among medical interns. Using biomaterial-covered mannequin.

    Science.gov (United States)

    Tatli, Ozgur; Turkmen, Suha; Imamoglu, Melih; Karaca, Yunus; Cicek, Mustafa; Yadigaroglu, Metin; Bayrak, Selen T; Asik, Olgun; Topbas, Murat; Turedi, Suleyman

    2017-10-01

    To develop a low-cost biomaterial-covered chest tube simulation model and assess its possible usefulness for developing the chest tube insertion skills among medical interns. Methods: This mannequin-based interventional study was performed in a University hospital setting. We included 63 physicians performing emergency medicine internship at the Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey, between January 2015 and March 2015. A dummy was prepared for training simulation using a display mannequin. Medical interns received instruction concerning pneumothorax and the chest tube procedure. A total of 63 medical interns participating in this interventional study were asked to insert a chest tube in a biomaterial-covered mannequin. A senior trainee scored their performance using a check list and the mean of the total scores was calculated (21 items; total score, 42). Results: The mean procedural score was 40.9 ± 1.3 of a possible 42. The maximum score of 42 was achieved by 39.7% of the medical interns, while another 33.3% achieved a score of 41. Of the participants, 85% succeeded in inserting the tube via an appropriate technique, achieving a score of 40 or more. Conclusion: Our results indicated that this model could be useful for effective training of medical interns for chest tube insertion, which is an important skill in emergency medicine. This biomaterial-covered model is inexpensive and its use can potentially be widened to improve training methods without significant financial demand.

  20. Procedure and device for extracting the end of a tube inserted into a hole in a tube plate

    International Nuclear Information System (INIS)

    1980-01-01

    When constructing heat exchangers and steam generators, particularly in the construction of steam generators for nuclear power stations, many small diameter tubes have to be secured into a very thick tube plate for instance 600 mm thick. This crimping or expanding of the tube is generally performed by rolling the internal surface of the tube inside a hole drilled right through the tube plate and slightly greater in diameter than the external diameter of the tube before the tube is rolled. To check the tubes for defects, it is necessary to extract certain tubes from the tube plate in order to move the tube to a testing and inspection point and examine the part of it that was secured in the plate hole. The invention concerns the uncrimping of these tubes [fr

  1. Cooperative learning using simulation to achieve mastery of nasogastric tube insertion.

    Science.gov (United States)

    Cason, Melanie Leigh; Gilbert, Gregory E; Schmoll, Heidi H; Dolinar, Susan M; Anderson, Jane; Nickles, Barbara Marshburn; Pufpaff, Laurie A; Henderson, Ruth; Lee, Frances Wickham; Schaefer, John J

    2015-03-01

    Traditionally, psychomotor skills training for nursing students involves didactic instruction followed by procedural review and practice with a task trainer, manikin, or classmates. This article describes a novel method of teaching psychomotor skills to associate degree and baccalaureate nursing students, Cooperative Learning Simulation Skills Training (CLSST), in the context of nasogastric tube insertion using a deliberate practice-to-mastery learning model. Student dyads served as operator and student learner. Automatic scoring was recorded in the debriefing log. Student pairs alternated roles until they achieved mastery, after which they were assessed individually. Median checklist scores of 100% were achieved by students in both programs after one practice session and through evaluation. Students and faculty provided positive feedback regarding this educational innovation. CLSST in a deliberate practice-to-mastery learning paradigm offers a novel way to teach psychomotor skills in nursing curricula and decreases the instructor-to-student ratio. Copyright 2015, SLACK Incorporated.

  2. Percutaneous Endoscopic Gastrostomy Tube Insertion in Neurodegenerative Disease: A Retrospective Study and Literature Review

    Directory of Open Access Journals (Sweden)

    Pamela Sarkar

    2017-05-01

    Full Text Available Background/Aims With the notable exceptions of dementia, stroke, and motor neuron disease, relatively little is known about the safety and utility of percutaneous endoscopic gastrostomy (PEG tube insertion in patients with neurodegenerative disease. We aimed to determine the safety and utility of PEG feeding in the context of neurodegenerative disease and to complete a literature review in order to identify whether particular factors need to be considered to improve safety and outcome. Methods A retrospective case note review of patients referred for PEG insertion by neurologists in a single neuroscience center was conducted according to a pre-determined set of standards. For the literature review, we identified references from searches of PubMed, mainly with the search items “percutaneous endoscopic gastrostomy” and “neurology” or “neurodegenerative disease.” Results Short-term mortality and morbidity associated with PEG in patients with neurological disease were significant. Age greater than 75 years was associated with poor outcome, and a trend toward adverse outcome was observed in patients with low serum albumin. Conclusions This study highlights the relatively high risk of PEG in patients with neurodegenerative disease. We present points for consideration to improve outcome in this particularly vulnerable group of patients.

  3. Multicentre survey of radiologically inserted gastrostomy feeding tube (RIG) in the UK

    International Nuclear Information System (INIS)

    Lowe, A.S.; Laasch, H.U.; Stephenson, S.; Butterfield, C.; Goodwin, M.; Kay, C.L.; Glancy, S.; Jackson, S.; Brown, D.; McLean, P.; Keanie, J.; Thrower, A.; Briggs, R.; Punekar, S.; Krishnan, S.; Thomas, B.; Yap, K.; Mullan, D.; Maskell, G.; Hancock, J.

    2012-01-01

    Aims: To evaluate the variance in current UK clinical practice and clinical outcomes for direct percutaneous radiologically inserted gastrostomy (RIG). Materials and methods: A prospective UK multicentre survey of RIG performed between October 2008 and August 2010 was performed through the British Society of Gastrointestinal and Abdominal Radiology (BSGAR). Results: Data from 684 patients were provided by 45 radiologists working at 17 UK centres. Two hundred and sixty-three cases (40%) were performed with loop-retained catheters, and 346 (53%) with balloon-retained devices. Sixty percent of all patients experienced pain in the first 24 h, but settled in the majority thereafter. Early complications, defined as occurring in the first 24 h, included minor bleeding (1%), wound infection (3%), peritonism (2%), and tube misplacement (1%). Late complications, defined as occurring between day 2 and day 30 post-procedure, included mild pain (30%), persisting peritonism (2%), and 30 day mortality of 1% (5/665). Pre-procedural antibiotics or anti-methicillin-resistant Staphylococcus aureus (MRSA) prophylaxis did not affect the rate of wound infection, peritonitis, post-procedural pain, or mortality. Ninety-three percent of cases were performed using gastropexy. Gastropexy decreased post-procedural pain (p < 0.001), but gastropexy-related complications occurred in 5% of patients. However, post-procedure pain increased with the number of gastropexy sutures used (p < 0.001). The use of gastropexy did not affect the overall complication rate or mortality. Post-procedure pain increased significantly as tube size increased (p < 0.001). The use of balloon-retention feeding tubes was associated with more pain than the deployment of loop-retention devices (p < 0.001). Conclusion: RIG is a relatively safe procedure with a mortality of 1%, with or without gastropexy. Pain is the commonest complication. The use of gastropexy, fixation dressing or skin sutures, smaller tube sizes, and

  4. Inadvertent chest tube insertion in congenital cystic adenomatoid malformation and congenital lobar emphysema-highlighting an important problem

    International Nuclear Information System (INIS)

    Prabhu, Shailesh M; Choudhury, Subhasis Roy; Solanki, Ravi S; Shetty, Gurucharan S; Agarwala, Surenderkumar

    2013-01-01

    Chest tube insertion in congenital cystic lung lesions is an important problem in children with acute respiratory distress having a cystic lucent lesion on chest radiograph. To evaluate the imaging findings and complications in cases of congenital cystic lung lesions with chest tube insertion and suggest the role of appropriate imaging for management of these patients. Chest radiographs and CT scans of children with congenital cystic lung lesions who had inadvertent chest tube insertion preoperatively were retrospectively reviewed for imaging appearances and complications. Fifteen patients comprising 10 cases of congenital cystic adenomatoid malformation (CCAM) and 5 cases of congenital lobar emphysema (CLE) were included. Majority of the cases were infants. CCAM was misdiagnosed as complicated pneumatocele (n = 5) and pneumothorax (n = 5), while CLE was misdiagnosed as tension pneumothorax (n = 5) on the chest radiograph findings. Final diagnosis was made on CT and operative findings with histopathology. Complications noted were pneumothorax, hydropneumothorax, and infection in cases of CCAM, and change in imaging appearance and pneumothorax in cases of CLE. Chest tube insertion in congenital cystic lesions increases the rate of associated complications. Chest CT has a definite role in early diagnosis and deciding appropriate management in these cases

  5. The usefulness of levin tube inserted drip infusion spiral CT: comparison with conventional method in subtotal gastrectomy patients

    International Nuclear Information System (INIS)

    Park, Young Jin; Kim, Young Hwan; Yoon, Jung Hee; Cha, Soon Joo; Kim, Jeong Sook; Kim, Sung Rok; Hur, Gham; Rhim, Hyun Chul

    1998-01-01

    The purpose of this study is to access the usefulness of newly designed Levin tube inserted drip infusion spiral CT for the evaluation of remnant stomach and anastomosis site in patients who have undergone subtotal gastrectomy for stomach cancer. A new technique named Levin tube inserted drip infusion spiral CT was used to prospectively study 23 patients. A 16Fr Levin tube was inserted into the remnant stomach; 500 ml of tap water was drip infused just before CT scanning and an additional 500 ml of water was infused during IV contrast injection. Water was infused by gravity, using a water bottle suspended at a height of 90 cm (Group A). The 31 patients who underwent conventional spiral CT scanning immediately after the divided ingestion of 900 ml diluted gastrografin were selected as a control group (Group B). The anatomic delineation of the anastomosis site was graded by two radiologists as excellent (3), good(2), fair (1) or poor (0). To evaluate the degree of distension, the maximal diameters of remnant stomach and the anastomosis site, and the thickness of the stomach wall, were also measured. In patients who had undergone subtobal gastrectomy, Levin tube inserted drip infusion spiral CT showed excellent anatomic delineation of the site of anastomosis and remnant stomach. We found that because it increases the distension of remnant stomach and the anastomosis site, this technique is effective for the evaluation of postoperative stomach. (author). 10 refs., 2 tabs., 3 figs

  6. The Effectiveness of Self-Expandable Metallic Stent Insertion in Treating Right-Sided Colonic Obstruction: A Comparison between SEMS and Decompression Tube Placement and an Investigation of the Safety and Difficulties of SEMS Insertion in Right Colons

    Directory of Open Access Journals (Sweden)

    Rintaro Moroi

    2014-01-01

    Full Text Available Objectives. Self-expandable metallic stent (SEMS is widely used to treat malignant colonic obstruction. However, most reports about SEMS insertion have concentrated on the left colon. This study aimed to (1 investigate the effectiveness of SEMS insertion compared with conventional decompression tube for right-sided colonic obstruction and (2 compare the safety and technical success of SEMS insertion between left- and right-sided colonic obstructions. Methods. The data from thirty-seven patients who underwent SEMS or conventional decompression tube placement for malignant colonic obstruction in our hospital were analyzed retrospectively. Technical and clinical success, complications, and technical difficulties were analyzed. We compared the results between SEMS insertion and decompression tube placement in right colons and the outcomes of SEMS insertion between right- and left-sided colonic obstructions. Results. For right colons, the clinical success rate of SEMS insertion (100% was significantly higher than that of decompression tube placement (55.9%. Concerning SEMS insertion, the technical difficulty and safety of SEMS insertion were similar between right- and left-sided colonic obstructions. Conclusion. SEMS insertion for right-sided colon is significantly more effective than conventional decompression tube placement, and this procedure was safer and less technically challenging than expected. SEMS insertion should be considered for treating right-sided malignant colonic obstruction.

  7. Heat transfer experiments in a wire-inserted tube at supercritical pressures

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yoon Yeong; Kim, Hwan Yeol; Yoo, Tae Ho

    2009-07-15

    The hydraulic diameter of a subchannel in a core concept developed at KAERI is 6.5 mm. The sub-channel is much smaller than that of the conventional PWR, and naturally a helical wire was considered as one of the candidates for a spacer. For simplicity the subchannel is simulated by a commercially available Inconel 625 tube of 6.32 mm ID with a helically-coiled spring steel wire insert of 1.3 mm OD. The medium is CO{sub 2}. The test pressures are 7.75 and 8.12 MPa corresponding to 1.05 and 1.1 times the critical pressure of CO{sub 2}, respectively. The mass flux and heat flux, which were in the range of 400 {approx} 1200 kg/m{sup 2}s and 30 {approx} 90 kW/m{sup 2} respectively, were varied at a given system pressure. The corresponding Reynolds numbers at the inlet spans between 2.5 x 10{sup 4} and 7.5 x 10{sup 4}. It was observed that the heat transfer was enhanced by almost twice in most of the tested enthalpy range except for in the the region far from the pseudocritical point. The test results revealed that the wire effect was sustained in the downstream up to 40-60 times the wire diameter. The temperature decreased in the first half of the span between contact points and it increased in the second half of the span.

  8. [Ahmed valve in glaucoma surgery].

    Science.gov (United States)

    Bikbov, M M; Khusnitdinov, I I

    This is a review on Ahmed valve application in glaucoma surgery. It contains, in particular, data on the Ahmed valve efficiency, results of experimental and histological studies of filtering bleb encapsulation, examines the use of antimetabolites and anti-VEGF agents, and discusses implantation techniques. The current appraisal of antimetabolites delivery systems integrated into the Ahmed valve is presented. Various complications encountered in practice and preventive measures are also covered.

  9. Fluoroscopically-guided transnasal insertion of ileus tube intestinal decompression in patients with inoperable malignant bowel obstruction

    International Nuclear Information System (INIS)

    Fang Shiming; Li Haili; Lin Qing; Mao Aiwu; Wu Shaoqiu; Jiang Haosheng; Cao Yan; Wang Zhenlei

    2011-01-01

    Objective: To assess the technical feasibility and effectiveness of fluoroscopically-guided transnasal insertion of ileus tube for intestinal decompression in the treatment of inoperable malignant bowel obstruction. Methods: A total of 211 patients with inoperable malignant bowel obstruction were enrolled in this study. The median KPS scale was 40 (ranged from 20 to 60). Under fluoroscopic guidance, transnasal insertion of ileus tube by using conventional technique or guidewire-catheter exchange technique was performed in all patients. The technical success rate, the clinical effective rate, the curative rate and adverse reactions as well as complications were documented. The correlation among the obstructive sites, obstruction causes and therapeutic effectiveness was analyzed. The ileus tube used in this study was a four-cavity and double-balloon catheter with a diameter of 16 F/18 f, which is produced by Cliny Company. Results: Transnasal drainage tube was successfully inserted into the proximal jejunum in all 211 patients with malignant bowel obstruction, and the total technical success rate was 100%. The initial technical success rate of the traditional technique and the catheter-guidewire exchange method was 85.5% (65/76) and 100% (135/135) respectively, the difference between the two was significant (P<0.05). After 24 hours, the clinical remission rate in the patients with high-level intestinal obstruction, lower-level intestinal obstruction and colorectal obstruction was 95.8% (46/48), 92.9% (117/126) and 83.8% (31/37), respectively. A follow-up of 4-245 days (mean 138 days) was conducted, and the total clinical cure rate was 27.5% (58/211). The clinical cure rate in small intestine obstruction and colorectal obstruction caused by primary tumor or recurrence was 12.7% (20/157) and 59.5% (22/37), respectively (P<0.05). The adverse reactions and complications included uncomfortable pharynx feeling or pain (99.1%, 199/221), the tube obstruction (23.2%, 49

  10. ''Push-pull'' gastrostomy: a new technique for percutaneous gastrostomy tube insertion in the neonate and young infant

    International Nuclear Information System (INIS)

    Cahill, A.M.; Kaye, R.D.; Fitz, C.R.; Towbin, R.B.

    2001-01-01

    Objective. To evaluate a newly developed method combining antegrade and retrograde techniques for percutaneous gastrostomy tube (PGT) insertion in the neonate and young infant. Materials and methods. From January 1994 to December 2000, 85 children (47 male, 38 female), mean age 4.5 months (range 0.44-9.13 months) underwent PGT insertion using the ''push-pull'' technique. With the addition, 57 children had a jejunostomy tube placed as well at or within 24 h of the PGT procedure. The mean weight was 3.74 kg, range 1.5-7.0 kg. The indications for the procedure included failure to thrive in 40 patients (25 %), static encephalopathy in 21 (25 %), neurological/congenital abnormalities in 12 (14 %), aspiration in 7 (8 %), and cardiac problems in 5 (6 %). Results. Eighty-five PGTs were successfully inserted in 85 children. One procedure was initially unsuccessful due to failed conscious sedation and was completed under general anesthesia. Four of 85 patients initially had attempted antegrade placement that failed, and the procedure was successfully completed using the ''push-pull'' method. One major complication occurred: a gastrocolic fistula at day 5 post-procedure, which was surgically repaired without sequelae. Tube-related problems included; tube dislodgement (n = 1) and procedure-related stomal infection (n = 3). Conclusion. The ''push-pull'' gastrostomy technique is a safe, effective method of percutaneous gastrostomy tube placement in neonates. It facilitates successful placement of the PGT in patients in whom the classic antegrade method is not possible. It has become the procedure of choice in this group. (orig.)

  11. Process to repair a steam generator tube by inserting a tubular sleeve and the associated sleeve

    International Nuclear Information System (INIS)

    Gaudin, J.P.

    1986-01-01

    The tubular sleeve is introduced in the tube and is mechanically expanded inside the tube plate, and is diametrally expanded at its upper part within the tube and outside the tube plate. Tightness is ensured by brazing the end part of the sleeve within the tube. The end part of the sleeve is brazed by melting of brazing metal previously applied to the outer surface of the sleeve of its end region. The invention applies more particularly to steam generators of pressurized water nuclear reactors [fr

  12. Advantages of Direct Insertion of a Straight Probe Without a Guide Tube During Anterior Odontoid Screw Fixation of Odontoid Fractures.

    Science.gov (United States)

    Park, Jin Hoon; Kang, Dong-Ho; Lee, Moon Kyu; Yoo, Byoungwoo; Jung, Sang Ku; Hwang, Soo-Hyun; Kim, Jeoung Hee; Oh, Sunkyu; Lee, Eun Jung; Jeon, Sang Ryong; Roh, Sung Woo; Rhim, Seung Chul

    2016-05-01

    A retrospective cohort study. The aim of this study was to compare the anterior odontoid screw fixation (AOSF) with a guide tube or with a straight probe. AOSF associates with several complications, including malpositioning, fixation loss, and screw breakage. Screw pull-out from the C2 body is the most common complication. All consecutive patients with type II or rostral shallow type III odontoid fractures who underwent AOSFs during the study period were enrolled retrospectively. The guide-tube AOSF method followed the standard published method except C3 body and C2-3 disc annulus rimming was omitted to prevent disc injury; instead, the guide tube was anchored at the anterior inferior C2 vertebra corner. After 2 screw pull-outs, the guide-tube cohort was analyzed to identify the cause of instrument failure. Thereafter, the straight-probe method was developed. A guide tube was not used. A small pilot hole was made on the most anterior side of the inferior endplate, followed by insertion of a 2.5 mm straight probe through the C2 body. Non-union and instrument failure rates and screw-direction angles of the guide-tube and straight-probe groups were recorded. The guide-tube group (n = 13) had 2 screw pull-outs and 1 non-union. The straight-probe group (n = 8) had no complications and significantly larger screw-direction angles than the guide-tube group (60.5 ± 4.63 vs. 54.8 ± 3.82 degrees; P = 0.047). Straight-probe AOSF yielded larger direction angles without injuring bone and disc. Complications were absent. The procedure was easier than guide-tube AOSF and assured sufficient engagement, even in horizontal fracture orientation cases. 3.

  13. Endobronchial intubation detected by insertion depth of endotracheal tube, bilateral auscultation, or observation of chest movements: randomised trial.

    Science.gov (United States)

    Sitzwohl, Christian; Langheinrich, Angelika; Schober, Andreas; Krafft, Peter; Sessler, Daniel I; Herkner, Harald; Gonano, Christopher; Weinstabl, Christian; Kettner, Stephan C

    2010-11-09

    To determine which bedside method of detecting inadvertent endobronchial intubation in adults has the highest sensitivity and specificity. Prospective randomised blinded study. Department of anaesthesia in tertiary academic hospital. 160 consecutive patients (American Society of Anesthesiologists category I or II) aged 19-75 scheduled for elective gynaecological or urological surgery. Patients were randomly assigned to eight study groups. In four groups, an endotracheal tube was fibreoptically positioned 2.5-4.0 cm above the carina, whereas in the other four groups the tube was positioned in the right mainstem bronchus. The four groups differed in the bedside test used to verify the position of the endotracheal tube. To determine whether the tube was properly positioned in the trachea, in each patient first year residents and experienced anaesthetists were randomly assigned to independently perform bilateral auscultation of the chest (auscultation); observation and palpation of symmetrical chest movements (observation); estimation of the position of the tube by the insertion depth (tube depth); or a combination of all three (all three). Correct and incorrect judgments of endotracheal tube position. 160 patients underwent 320 observations by experienced and inexperienced anaesthetists. First year residents missed endobronchial intubation by auscultation in 55% of cases and performed significantly worse than experienced anaesthetists with this bedside test (odds ratio 10.0, 95% confidence interval 1.4 to 434). With a sensitivity of 88% (95% confidence interval 75% to 100%) and 100%, respectively, tube depth and the three tests combined were significantly more sensitive for detecting endobronchial intubation than auscultation (65%, 49% to 81%) or observation(43%, 25% to 60%) (Pauscultation to detect inadvertent endobronchial intubation. But even experienced physicians will benefit from inserting tubes to 20-21 cm in women and 22-23 cm in men, especially when high

  14. The effects of oral sucrose on pain due to nasogastric tube insertion in premature infants: A crossover clinical trial

    Directory of Open Access Journals (Sweden)

    Jebreili M

    2014-11-01

    Full Text Available Background and Objective: Pain in neonates may have adverse impacts. Therefore, relieving pain through harmless, simple, and applicable methods, in order to prevent its dangerous consequences, is of great importance. The aim of the present study is to determine the impact of oral sucrose on relieving nasogastric tube insertion pain in premature neonates. Materials and Method: The present study is a crossover clinical trial on 38 preterm infants (gestational age between 28-34 weeks hospitalized in Bistonoh-e-Bahman Hospital, Tabriz, Iran, in 2013. The subjects were selected by convenience sampling and divided into two groups using randomized block design. In the first group, nasogastric tube insertion was carried out in the routine way for the first time, and for the second time, by administration of oral sucrose. In the second group, the procedure was performed in the reverse order of that in the first group. In both groups the emerging pain was measured by the Premature Infant Pain Profile (PIPP tool 2 minutes before, during, and 5 minutes after the procedure. Data were analyzed using, chi-square t-test, Students' independent test, paired t-test, and repeated measures ANOVA in SPSS version 18 to examine the trend of change in pain in time. P values of less than 0.05 were considered statistically significant. Results: The results showed that oral sucrose reduces the pain response of infants. The mean pain score during the insertion of nasogastric tube and administration of oral sucrose was 5.95 ± 2.35 and during routine procedures was 9.93 ± 2.89 (P < 0.001. The mean pain score 5 minutes after insertion of nasogastric tube with administration of oral sucrose was 3.66 ± 0.57 and routine procedure was 6.38 ± 0.83 (P = 0.017. Conclusion: It was revealed that oral sucrose can relieve pain caused by nasogastric tube insertion. Therefore, its implementation as a harmless and simple method can reduce pain in preterm infants.

  15. Ahmed glaucoma valve implant: surgical technique and complications

    Directory of Open Access Journals (Sweden)

    Riva I

    2017-02-01

    Full Text Available Ivano Riva,1 Gloria Roberti,1 Francesco Oddone,1 Anastasios GP Konstas,2 Luciano Quaranta3 1IRCCS “Fondazione GB Bietti per l’Oftalmologia”, Rome, Italy; 21st University Department of Ophthalmology, Glaucoma Unit, AHEPA Hospital, Thessaloniki, Greece; 3Department of Medical and Surgical Specialties, Section of Ophthalmology, University of Brescia, Brescia, Italy Abstract: Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications. Keywords: glaucoma, surgical technique, glaucoma drainage devices, Ahmed glaucoma valve, complications

  16. The effect of an Ahmed glaucoma valve implant on corneal endothelial cell density in children with glaucoma secondary to uveitis.

    Science.gov (United States)

    Kalinina Ayuso, Viera; Scheerlinck, Laura M; de Boer, Joke H

    2013-03-01

    To assess the effect of Ahmed glaucoma valve implants on corneal endothelial cell density (ECD) in children with uveitic glaucoma. Cross-sectional study. setting: Institutional. patientpopulation: Eighty eyes from 42 patients diagnosed with uveitis before the age of 16. Twenty-eight eyes had an Ahmed glaucoma valve implant because of secondary glaucoma. Fifty-two eyes without an implant served as controls. intervention orobservationprocedure(s): Corneal ECD was examined cross-sectionally using a noncontact specular microscope. Univariate and multivariate generalized estimating equations analyses with correction for paired eyes were performed. mainoutcomemeasure(s): Correlation of ECD with the presence of an Ahmed glaucoma valve implant and with the time following implantation. ECD was significantly lower in the Ahmed glaucoma valve group than in controls (2359 and 3088 cells/mm(2), respectively; P Ahmed glaucoma valve implantation. Presence of an Ahmed glaucoma valve implant, previous intraocular surgery, age, duration of uveitis, and history of corneal touch by the implant tube were all significantly associated with decreased ECD. Following a multivariate analysis, presence of an Ahmed glaucoma valve implant (B = -340; adjusted P Ahmed glaucoma valve implantation was highly correlated with decreased ECD (B = -558, P Ahmed glaucoma valve implants in children with uveitic glaucoma are independently associated with decreased ECD, and this effect is associated with the time interval following Ahmed glaucoma valve implantation. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Influences of the wavy surface inserted in the middle of a circular tube heat exchanger on thermal performance

    Energy Technology Data Exchange (ETDEWEB)

    Jedsadaratanancai, Withada [King Mongkut' s Institute of Technology Ladkrabang, Bangkok (Thailand); Boonloi, Amnart [King Mongkut' s University of Technology North Bangkok, Bangkok (Thailand)

    2015-09-15

    Numerical investigations on flow topology, heat transfer behavior and performance evaluation in a circular tube inserted with various configurations of wavy surfaces, Inclined wavy surface (IWS), V-downstream wavy surface (VDWS), V-Upstream wavy surface (VUWS) are presented. The effects of the flow attack angles; 20 .deg., 30 .deg., 45.deg. and 60.deg. are studied for the Reynolds numbers, Re = 100-2000. The numerical results are compared with the smooth circular tube with no wavy surface and the previous works. It is found that the IWS, VDWS and VUWS can produce longitudinal vortex flow and impinging jet of the fluid flow like inclined baffle, V-downstream baffle and V-Upstream baffle, respectively, but give lower friction loss. The flow phenomena created by the wavy surfaces help to augment the heat transfer rate and thermal performance in the test tube. In the range studied, the order of enhancement for heat transfer rate is around 1.40-3.75, 1.60-6.25 and 1.30-5.80 times higher than the smooth tube for IWS, VDWS and VUWS, respectively. Moreover, the maximum thermal performance, presented in terms of the Thermal enhancement factor (TEF), is found to be about 1.60, 2.40 and 2.10, respectively, for IWS, VUWS and VDWS.

  18. Heat transfer intensification within tube recuperator by inserting secondary emitters inside air channels

    International Nuclear Information System (INIS)

    Sandor, P.; Soroka, B.; Kudryavtsev, V.; Zgurskyy, V.

    2009-01-01

    The research program was stipulated by reduction the service life of the tube recuperators of reheating furnaces at DUNAFERR metallurgical works in Dunaujvaros (Hungary) while replacement the natural gas by coke - oven gas as a furnace fuel took place and air preheating temperature was increased. The tests procedure consists in comparison of temperature and pressure distributions by air flows preheating under air moving inside the tube loops. Advantages of new recuperator design compared to ordinary one have been proven by validation of concept for adequacy to the testing results. The first tests have demonstrated enhancement of local specific and total heat fluxes transferred from flue gases to air flow within the MD tube loops in comparison with those for BD loops by 25 to 45% - dependence on temperature level within the heating (furnace) chamber and on preheated air flow rate. (author)

  19. Interventions for children with ear discharge occurring at least two weeks following grommet (ventilation tube) insertion

    NARCIS (Netherlands)

    Venekamp, Roderick P; Javed, Faisal; van Dongen, Thijs Ma; Waddell, Angus; Schilder, Anne Gm

    2016-01-01

    BACKGROUND: Ear discharge (otorrhoea) is common in children with grommets (ventilation/tympanostomy tubes); the proportion of children developing discharge ranges from 25% to 75%. The most common treatment strategies include oral broad-spectrum antibiotics, antibiotic eardrops or those containing a

  20. Experimental and numerical investigation on heat transfer augmentation in a circular tube under forced convection with annular differential blockages/inserts

    Science.gov (United States)

    Waghole, D. R.

    2018-01-01

    Investigation on heat transfer by generating turbulence in the fluid stream inside the circular tube is an innovative area of research for researchers. Hence, many techniques are been investigated and adopted for enhancement of heat transfer rate to reduce the size and the cost of the heat exchanger/circular tube. In the present study the effect of differential solid ring inserts /turbulators on heat transfer, friction factor of heat exchanger/circular tube was evaluated through experimentally and numerically. The experiments were conducted in range of 3000 ≤Re≤ 6500 and annular blockages 0 ≤ɸ≤50 %. The heat transfer rate was higher for differential combination of inserts as compared to tube fitted with uniform inserts. The maximum heat transfer was obtained by the use of differential metal circular ring inserts/blockages. From this study, Nusselt number, friction factor and enhancement factor are found as 2.5-3.5 times, 12% - 50.5% and 155% - 195%, respectively with water. Finally new possible correlations for predicting heat transfer and friction factor in the flow of water through the circular tube with differential blockages/inserts are proposed.

  1. Heat transfer and pressure drop studies of TiO2/DI water nanofluids in helically corrugated tubes using spiraled rod inserts

    Science.gov (United States)

    Anbu, S.; Venkatachalapathy, S.; Suresh, S.

    2018-05-01

    An experimental study on the convective heat transfer and friction factor characteristics of TiO2/DI water nanofluids in uniformly heated plain and helically corrugated tubes (HCT) with and without spiraled rod inserts (SRI) under laminar flow regime is presented in this paper. TiO2 nanoparticles with an average size of 32 nm are dispersed in deionized (DI) water to form stable suspensions containing 0.1, 0.15, 0.2, and 0.25% volume concentrations of nanoparticles. It is found that the inclusion of nanoparticles to DI water ameliorated Nusselt number which increased with nanoparticles concentration upto 0.2%. Two spiraled rod inserts made of copper with different pitches (pi = 50 mm and 30 mm) are inserted in both plain and corrugated tubes and it is found that the addition of these inserts increased the Nusselt number substantially. For Helically corrugated tube with lower pitch and maximum height of corrugation (pc = 8 mm, hc = 1 mm) with 0.2% volume concentration of nanoparticles, a maximum enhancement of 15% in Nusselt number is found without insert and with insert having lower pitch (pi = 30 mm) the enhancement is 34% when compared to DI water in plain tube. The results on friction factor show a maximum penalty of about 53.56% for the above HCT.

  2. Complications of ventilation tube insertion in children with and without cleft palate: a nested case-control comparison.

    Science.gov (United States)

    Smillie, Ian; Robertson, Sophie; Yule, Anna; Wynne, David M; Russell, Craig J H

    2014-10-01

    Optimizing hearing in patients with cleft lip and/or palate (CLP) by early recognition and management of otitis media with effusion is essential for speech development. Some evidence has suggested higher complication rates from ventilation tube (VT) insertion in patients with CLP and has led to a trend not to treat these patients surgically. However, studies have failed to match comparison groups for age and sex. To compare complication rates from VT insertion in pediatric patients with and without CLP. The study used a nested case-control design to evaluate 60 pediatric patients with CLP who underwent VT insertion at a children's hospital. The control group of age- and sex-matched patients was selected from a database of 2943 VT insertions. All patients were administered general anesthesia and underwent VT insertion by a pediatric otorhinolaryngology (ENT) team. The primary outcomes were numbers of otorrhea complications. Secondarily, rates of attendance at an ENT clinic specifically for complications were evaluated. Finally, numbers of complications other than otorrhea were assessed but not statistically analyzed owing to the varied types and low numbers in each group. The control cohort had 151 documented cases of otorrhea compared with 121 in the CLP group (ratio 1.25:1); the difference between groups was not statistically significant (P = .52). There was no significant difference in mean ENT clinic visits per patient for complications between groups (0.80 in the CLP group, 0.78 for controls) (P = .66). Regarding complications other than otorrhea, the control group reported more than the CLP group (43 vs 25; ratio, 1.7:1). Complication rates of VT placement among patients with CLP were not higher than those among patients without CLP. Therefore, treatment with VT insertion should be administered to patients with CLP under the same guidelines as for those without CLP. Indeed, there could be an argument for a shift in practice toward more aggressive

  3. Incidence of Complications Developed after the Insertion of Ventilation Tube in Children under 6 years old in 2008-2009

    Directory of Open Access Journals (Sweden)

    Nader Saki

    2012-01-01

    Full Text Available Introduction: One of the main treatments of chronic otitis media with effusion is ventilation of the middle ear with a ventilation tube (VT. The objective of this study was to determine the incidence and the types of VT complications in children with otitis media with effusion in Ahwaz. Materials and Methods: In this prospective study, the medical records of 208 children (52 male and 35 female in Imam Khomeini and Apadana hospitals were reviewed. The children were between 10 months and 6 years old. The patients were followed up 12-18 months after ventilation tube insertion. We reviewed age, sex, postoperative otorrhea, eardrum atrophy, tympanosclerosis and persistent perforation. In all these patients, the indication for surgery was chronic middle ear effusion. The data were analyzed and presented as numbers and percentages using SPSS17.0. Results: Transient otorrhea occurred in 12.5% and delayed otorrhea in 8.2%. Otorrhea non-responsive to medical treatment was seen in 1.9%. Complications after tympanostomy tube extrusion included atrophy (27.8% myringosclerosis (37.9%, and persistent perforation (2.4%.The average extrusion time was 10.5 ±5 months (ranging between 3-22 months. Conclusion: After extrusion of the ventilation tube, patients should be followed up regularly for recurrence of OME. Myringosclerosis, tympanic membrane atrophy and otorrhea are the most common complications of otitis media with effusion. However, they are generally insignificant. Consequently, in the majority of these complications, there is no need for any treatment.

  4. Endoscopically placed guide wire assisted nasogastric tube insertion for palliation of absolute dysphagia in patients with incurable esophageal cancer

    Directory of Open Access Journals (Sweden)

    Purkayastha Joydeep

    2006-01-01

    Full Text Available Carcinoma of the esophagus is a dreadful disease because it causes a lot of distress to the patient due to its adverse effects on swallowing. Many patients present with large incurable disease or undergo disease progression and become incurable. Such patients are advised palliative and symptomatic care. The most distressing symptom that requires palliation in such patients is dysphagia. Many procedures are available for relief of dysphagia, but these are not readily available or are costly. We describe a simple, safe, cost effective and easy to do procedure for palliation of malignant dysphagia by insertion of Ryle′s tube over a endoscopically placed guide wire especially suitable for patients of the poor socio-economic strata.

  5. Ahmed glaucoma valve implant: surgical technique and complications.

    Science.gov (United States)

    Riva, Ivano; Roberti, Gloria; Oddone, Francesco; Konstas, Anastasios Gp; Quaranta, Luciano

    2017-01-01

    Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications.

  6. Ahmed glaucoma valve in children: A review☆

    Science.gov (United States)

    Nassiri, Nariman; Nouri-Mahdavi, Kouros; Coleman, Anne L.

    2011-01-01

    Pediatric glaucoma is potentially a blinding disease. Although goniotomy and trabeculotomy are associated with good early success rates, eventually 20% of these procedures fail and many children will require additional surgery to control the IOP in the long-term. In this review, we reported that adequate IOP control can be achieved with the placement of Ahmed glaucoma valve and can last 5 or more years. However, most patients will need one or more glaucoma medications at some point after surgery. In addition, the implants may be associated with pupillary irregularities, lenticular opacification as well as tube-related complications, particularly in the first year of life, as the globe is enlarging with age. PMID:23960945

  7. Definition of the minimum longitude of insert in the rebuilding of Charpy test tubes for surveillance and life extension of vessels in Mexico

    International Nuclear Information System (INIS)

    Romero C, J.; Hernandez C, R.; Rocamontes A, M.

    2011-11-01

    In the National Institute of Nuclear Research (Mexico) a welding system for the rebuilding of Charpy test tubes has been developed, automated, qualified and used for the surveillance of the mechanical properties (mainly embrittlement) of the vessel. This system uses the halves of the rehearsed Charpy test tubes of the surveillance capsules extracted of the reactors, to obtain, of a rehearsed test tube, two reconstituted test tubes. This rebuilding process is used so much in the surveillance program like in the potential extension of the operation license of the vessel. To the halves of Charpy test tubes that have been removed the deformed part by machine are called -insert- and in a very general way the rebuilding consists in weld with the welding process -Stud Welding- two metallic implants in the ends of the insert, to obtain a reconstituted test tube. The main characteristic of this welding are the achieved small dimensions, so much of the areas welded as of the areas affected by the heat. The applicable normative settles down that the minim longitude of the insert for the welding process by Stud Welding it should be of 18 mm, however according to the same normative this longitude can diminish if is demonstrated analytic or experimentally that the central volume of 1 cm 3 in the insert is not affected. In this work the measurement of the temperature profiles to different distances of the welding interface is presented, defining an equation for the maximum temperatures reached in function of the distance, on the other hand the real longitude affected in the test tube by means of metallography is determined and this way the minimum longitude of the insert for this developed rebuilding system was determined. (Author)

  8. Evaluation of App-Based Serious Gaming as a Training Method in Teaching Chest Tube Insertion to Medical Students: Randomized Controlled Trial.

    Science.gov (United States)

    Haubruck, Patrick; Nickel, Felix; Ober, Julian; Walker, Tilman; Bergdolt, Christian; Friedrich, Mirco; Müller-Stich, Beat Peter; Forchheim, Franziska; Fischer, Christian; Schmidmaier, Gerhard; Tanner, Michael C

    2018-05-21

    The insertion of a chest tube should be as quick and accurate as possible to maximize the benefit and minimize possible complications for the patient. Therefore, comprehensive training and assessment before an emergency situation are essential for proficiency in chest tube insertion. Serious games have become more prevalent in surgical training because they enable students to study and train a procedure independently, and errors made have no effect on patients. However, up-to-date evidence regarding the effect of serious games on performance in procedures in emergency medicine remains scarce. The aim of this study was to investigate the serious gaming approach in teaching medical students an emergency procedure (chest tube insertion) using the app Touch Surgery and a modified objective structural assessment of technical skills (OSATS). In a prospective, rater-blinded, randomized controlled trial, medical students were randomized into two groups: intervention group or control group. Touch Surgery has been established as an innovative and cost-free app for mobile devices. The fully automatic software enables users to train medical procedures and afterwards self-assess their training effort. The module chest tube insertion teaches each key step in the insertion of a chest tube and enables users the meticulous application of a chest tube. In contrast, the module "Thoracocentesis" discusses a basic thoracocentesis. All students attended a lecture regarding chest tube insertion (regular curriculum) and afterwards received a Touch Surgery training lesson: intervention group used the module chest tube insertion and the control group used Thoracocentesis as control training. Participants' performance in chest tube insertion on a porcine model was rated on-site via blinded face-to-face rating and via video recordings using a modified OSATS tool. Afterwards, every participant received an individual questionnaire for self-evaluation. Here, trainees gave information about their

  9. Evaluation of App-Based Serious Gaming as a Training Method in Teaching Chest Tube Insertion to Medical Students: Randomized Controlled Trial

    Science.gov (United States)

    Ober, Julian; Walker, Tilman; Bergdolt, Christian; Friedrich, Mirco; Müller-Stich, Beat Peter; Forchheim, Franziska; Fischer, Christian; Schmidmaier, Gerhard; Tanner, Michael C

    2018-01-01

    Background The insertion of a chest tube should be as quick and accurate as possible to maximize the benefit and minimize possible complications for the patient. Therefore, comprehensive training and assessment before an emergency situation are essential for proficiency in chest tube insertion. Serious games have become more prevalent in surgical training because they enable students to study and train a procedure independently, and errors made have no effect on patients. However, up-to-date evidence regarding the effect of serious games on performance in procedures in emergency medicine remains scarce. Objective The aim of this study was to investigate the serious gaming approach in teaching medical students an emergency procedure (chest tube insertion) using the app Touch Surgery and a modified objective structural assessment of technical skills (OSATS). Methods In a prospective, rater-blinded, randomized controlled trial, medical students were randomized into two groups: intervention group or control group. Touch Surgery has been established as an innovative and cost-free app for mobile devices. The fully automatic software enables users to train medical procedures and afterwards self-assess their training effort. The module chest tube insertion teaches each key step in the insertion of a chest tube and enables users the meticulous application of a chest tube. In contrast, the module “Thoracocentesis” discusses a basic thoracocentesis. All students attended a lecture regarding chest tube insertion (regular curriculum) and afterwards received a Touch Surgery training lesson: intervention group used the module chest tube insertion and the control group used Thoracocentesis as control training. Participants’ performance in chest tube insertion on a porcine model was rated on-site via blinded face-to-face rating and via video recordings using a modified OSATS tool. Afterwards, every participant received an individual questionnaire for self-evaluation. Here

  10. Postoperative Complications in the Ahmed Baerveldt Comparison Study during Five Years of Follow-up

    Science.gov (United States)

    Budenz, Donald L.; Feuer, William J.; Barton, Keith; Schiffman, Joyce; Costa, Vital P.; Godfrey, David G.; Buys, Yvonne M.

    2016-01-01

    PURPOSE To compare the late complications in the Ahmed Baerveldt Comparison Study during 5 years of follow-up. DESIGN Multicenter, prospective, randomized clinical trial. METHODS SETTINGS Sixteen international clinical centers. STUDY POPULATION Two hundred seventy six subjects aged 18 to 85 years with previous intraocular surgery or refractory glaucoma with intraocular pressure of > 18 mmHg. INTERVENTIONS Ahmed Glaucoma Valve FP7 or Baerveldt Glaucoma Implant BG 101-350. MAIN OUTCOME MEASURES Late postoperative complications (beyond 3 months), reoperations for complications, and decreased vision from complications. RESULTS Late complications developed in 56 subjects (46.8 ± 4.8 5 year cumulative % ± SE) in the Ahmed Glaucoma Valve group and 67 (56.3 ± 4.7 5 year cumulative % ± SE) in the Baerveldt Glaucoma Implant group (P = 0.082). The cumulative rates of serious complications were 15.9% and 24.7% in the Ahmed Glaucoma Valve and Baerveldt Glaucoma Implant groups respectively (P = 0.034) although this was largely driven by subjects who had tube occlusions in the two groups (0.8% in the Ahmed Glaucoma Valve group and 5.7% in the Baerveldt Glaucoma Implant group, P = 0.037). Both groups had a relatively high incidence of persistent diplopia (12%) and corneal edema (20%), although half of the corneal edema cases were likely due to pre-existing causes other than the aqueous shunt. The incidence of tube erosion was 1% and 3% in the Ahmed Glaucoma Valve and Baerveldt Glaucoma Implant groups, respectively (P = 0.04). CONCLUSIONS Long term rates of vision threatening complications and complications resulting in reoperation were higher in the Baerveldt Glaucoma Implant than the Ahmed Glaucoma Valve group over 5 years of follow-up. PMID:26596400

  11. Effect of Ahmed valve implantation on late neovascular glaucoma

    Directory of Open Access Journals (Sweden)

    Ping-An Mao

    2013-09-01

    Full Text Available AIM: To discuss the effect and safety of Ahmed valve implantation in late neovascular glaucoma. METHODS: The Ahmed glaucoma valve were implanted in 41 eyes(41 caseswith late neovascular glaucoma, the follow-up was 12 months on average, intraocular pressure was recorded at 1 day, 1 week, 1 month, 3, 6, 12 months respectively after operation and compared with that before operation, at the same time, the complications and treatment were analyzed.RESULTS: The mean intraocular pressure before operation, 1 day, 1 week, 1 month, 3, 6, 12 months after operation was 59.83±5.53, 19.27±8.19, 19.69±6.86, 20.67±6.73, 21.05±6.93, 21.49±7.42, 22.14±8.08mmHg, the mean intraocular pressure before operation was higher than that after operation and the difference was obvious in statistics. Major complications included hyphema, low intraocular pressure early postoperation, shallow anterior chamber, obstruction of the tube, the plate wrapped or exposed.CONCLUSION: Ahmed valve implantation is an effective method to treatlate neovascular glaucoma.

  12. Experimental Analysis of the Thermo-Hydraulic Performance on a Cylindrical Parabolic Concentrating Solar Water Heater with Twisted Tape Inserts in an Absorber Tube

    Science.gov (United States)

    Kumar, Birendra; Nayak, Rajen Kumar; Singh, S. N.

    2018-05-01

    A twisted tape inserted in an absorber tube may be an excellent option to enhance the performance of a cylindrical parabolic concentrating solar collector (CPC). The present work is an experimental study of the flow and heat transfer with and without twisted tape inserts in the absorber tube of a CPC. Results are presented for mass flow rates of water, ṁ=0.0198-0.0525 kg/s, twist ratio, y=5-10 and Reynolds number, Re=2577.46-6785.55. In the present study, we found that the outlet water temperature, collector efficiency and Nusselt number (Nu) are higher in the twisted tapes as compared to those without the twisted tape inserts in the absorber tube of the CPC. For fixed mass flow rate of water ṁ, the To and η increased with the decrease in twist ratio, y, and is higher in lower twist ratio, y=5, of the twisted tapes. The whole experiment was performed at the Indian Institute of Technology (ISM) in Dhanbad, India during the months of March-April 2017. Based on the experimental data, the correlations for the Nu and friction factor were also developed.

  13. Nasogastric feeding tubes from a neonatal department yield high concentrations of potentially pathogenic bacteria- even 1 d after insertion

    DEFF Research Database (Denmark)

    Meinich Petersen, Sandra; Greisen, Gorm; Krogfelt, Karen Angeliki

    2016-01-01

    probiotic administration through the tube. RESULTS: Out of the 94 NG-tubes, 89% yielded more than 1,000 colony-forming units (CFU)/ml bacteria, and 55% yielded the potentially pathogenic Enterobacteriaceae and/or Staphylococcus aureus. The mean concentration in the yield was 5.3 (SD: 2.1, maximum 9.4) log10......BACKGROUND: Preterm infants are vulnerable to pathogens and at risk of developing necrotizing enterocolitis (NEC) or sepsis. Nasogastric feeding tubes (NG-tubes) might contaminate feeds given through them due to biofilm formation. We wanted to determine if there is a rationale in replacing NG......-tubes more often to reduce contamination. METHODS: We conducted an observational study of used NG-tubes from a tertiary neonatal department. After removal, we flushed a 1-ml saline solution through the tube, determined the density of bacteria by culture, and related it to the duration of use and any...

  14. Proposed examination of defect detection of magnetic tube where alternating probe in type of insertion is used

    International Nuclear Information System (INIS)

    Kiya, Atsushi; Gotoh, Yuji; Sakurai, Kenta

    2008-01-01

    In various plants in the thermal power plant and the nuclear plant, a lot of steel tubes are used for various places such as heat exchangers, and these steel tubes should inspect regular for a healthy securing of the plant. Then, the outer side defect inspection of the magnetic substance steel tube using an electromagnetic phenomenon was examined in this research. It is shown that the inspection of the outer side defect on a steel tube with baffle is possible using the proposed method. (author)

  15. Evaluation of two different operations to implant the Ahmed glaucoma valve in patients with refractory glaucoma

    Directory of Open Access Journals (Sweden)

    Yue Wu

    2016-04-01

    Full Text Available AIM:To evaluate the efficacy and safety of Ahmed glaucoma valve(AGVimplantation surgery using different methods. METHODS:This was a retrospective study of patients with refractory glaucoma in whom AGV implantation was performed between June 2011 and September 2014. According to the method of tube insertion into the anterior chamber, the sample was divided into two groups, needle-generated scleral tunnel and scleral flap. The surgical success rate, intraocular pressure(IOP, number of antiglaucoma medications used, best correct visual acuity, postoperative complications, and operation duration were analyzed between the two groups. RESULTS:Compared with preoperative data, the two groups showed statistically significant decrease on IOP and the number of antiglaucoma medication used at all follow-up points(PP=0.932; however, statistically significant differences were detected when flat anterior chamber complications between the needle-generated scleral tunnel group(6%and the scleral flap group(24%were compared(P=0.032. CONCLUSION:AGV implantation may be an effective method in managing refractory glaucoma, since the two methods have similar efficacy. However, the needle-generated scleral tunnel technique application could greatly decrease the incidence of flat anterior chamber complications and decrease the duration of the operation.

  16. Combination of helical ferritic-steel inserts and flux-tube-expansion divertor for the heat control in tokamak DEMO reactor

    International Nuclear Information System (INIS)

    Takizuka, T.; Tokunaga, S.; Hoshino, K.; Shimizu, K.; Asakura, N.

    2015-01-01

    Edge localized modes (ELMs) in the H-mode operation of tokamak reactors may be suppressed/mitigated by the resonant magnetic perturbation (RMP), but RMP coils are considered incompatible with DEMO reactors under the strong neutron flux. We propose an innovative concept of the RMP without installing coils but inserting ferritic steels of the helical configuration. Helically perturbed field is naturally formed in the axisymmetric toroidal field through the helical ferritic steel inserts (FSIs). When ELMs are avoided, large stationary heat load on divertor plates can be reduced by adopting a flux-tube-expansion (FTE) divertor like an X divertor. Separatrix shape and divertor-plate inclination are similar to those of a simple long-leg divertor configuration. Combination of the helical FSIs and the FTE divertor is a suitable method for the heat control to avoid transient ELM heat pulse and to reduce stationary divertor heat load in a tokamak DEMO reactor

  17. Observation of double loop insertion of silicone rubber tube anastomosis method combined with "Z" flap repair in the treatment of lacrimal ductule laceration

    Directory of Open Access Journals (Sweden)

    Rui Hou

    2017-03-01

    Full Text Available AIM: To investigate the clinical curative effect of double loop insertion of silicone rubber tube combined with "Z" flap repair in the treatment of laceration of eyelid with canaliculus laceration. METHODS: The paper reviewed 45 cases of laceration of eyelid with laceration canaliculus, caused by trauma, which were treated in my hospital from January 2014 to January 2016. In the process of anastomosis of lacrimal duct and suture of eyelid laceration, either the method of single spinal anesthesia tube placement on skin contraposition suture or the method of dual annular silicone tube placement combined with the word "Z" flap repair was used. We compared the two methods and studied the possible complications like eyelid varus and valgus, lacrimal point valgus, eyelid scar, anastomotic dehiscence again. RESULTS: Out of the 22 cases in which the patients chose the single spinal anesthesia tube implantation on skin suture, 21 cases succeeded and patients received lacrimal duct patency results after extubation; and 1 case anastomosis failed. Complications: 20 cases had different degree of complications and the impact on their appearances were significant. Out of the 23 cases in which the patients chose double passage annular silicone tube joint prosthesis implantation Z flap, 23 received extubation results lacrimal patency or almost patency, the anastomosis of patients was successful. Complications: in two cases, patients had mild eyelid entropion and pomatum varus. Both eyelid deformity and severe wound tear did not occur in all cases again. Scar was not obvious. The success rate of anastomosis between the two groups was not significantly different(P=0.4889. To compare the rate of complications, there were significant differences(χ2=30.42, PCONCLUSION: The application of dual ring implantation silicon tube combined with the word "Z" flap repair in the treatment of lacrimal canaliculi laceration of eyelid laceration ensured the success rate of

  18. Risk of bleeding in patients undergoing percutaneous endoscopic gastrotrostomy (PEG tube insertion under antiplatelet therapy: a systematic review with a meta-analysis

    Directory of Open Access Journals (Sweden)

    Alfredo J. Lucendo

    2015-03-01

    Full Text Available Background and aim: Patients undergoing percutaneous endoscopic gastrostomy (PEG tube placement often are under antiplatelet therapy with a potential thromboembolic risk if these medications are discontinued. This systematic review aims to assess if maintaining aspirin and/or clopidogrel treatment increases the risk of bleeding following PEG placement. Methods: A systematic search of the MEDLINE, EMBASE, and SCOPUS databases was developed for studies investigating the risk of bleeding in patients on antiplatelet therapy undergoing PEG tube insertion. Summary estimates, including 95 % confidence intervals (CI, were calculated. A fixed or random effects model was used depending on heterogeneity (I². Publication bias risks were assessed by means of funnel plot analysis. Results: Eleven studies with a total of 6,233 patients (among whom 3,665 were undergoing antiplatelet treatment, met the inclusion criteria and were included in the quantitative summary. Any PEG tube placement-related bleeding was found in 2.67 % (95 % CI 1.66 %, 3.91 % of the entire population and in 2.7 % (95 % CI 1.5 %, 4.1 % of patients not receiving antiplatelet therapy. Pooled relative risk (RR for bleeding in patients under aspirin, when compared to controls, was 1.43 (95 % CI 0.89, 2.29; I² = 0 %; pooled RR for clopidogrel was 1.21 (95 % CI 0.48, 3.04; I² = 0 % and for dual antiplatelet therapy, 2.13; (95 % CI 0.77, 5.91; I² = 47 %. No significant publication bias was evident for the different medications analyzed. Conclusion: Antiplatelet therapy was safe among patients undergoing PEG tube insertion. Future prospective and randomized studies with larger sample sizes are required to confirm the results of this study.

  19. Numerical investigation of heat transfer and friction factor characteristics in a circular tube fitted with V-cut twisted tape inserts.

    Science.gov (United States)

    Salman, Sami D; Kadhum, Abdul Amir H; Takriff, Mohd S; Mohamad, Abu Bakar

    2013-01-01

    Numerical investigation of the heat transfer and friction factor characteristics of a circular fitted with V-cut twisted tape (VCT) insert with twist ratio (y = 2.93) and different cut depths (w = 0.5, 1, and 1.5 cm) were studied for laminar flow using CFD package (FLUENT-6.3.26). The data obtained from plain tube were verified with the literature correlation to ensure the validation of simulation results. Classical twisted tape (CTT) with different twist ratios (y = 2.93, 3.91, 4.89) were also studied for comparison. The results show that the enhancement of heat transfer rate induced by the classical and V-cut twisted tape inserts increases with the Reynolds number and decreases with twist ratio. The results also revealed that the V-cut twisted tape with twist ratio y = 2.93 and cut depth w = 0.5 cm offered higher heat transfer rate with significant increases in friction factor than other tapes. In addition the results of V-cut twist tape compared with experimental and simulated data of right-left helical tape inserts (RLT), it is found that the V-cut twist tape offered better thermal contact between the surface and the fluid which ultimately leads to a high heat transfer coefficient. Consequently, 107% of maximum heat transfer was obtained by using this configuration.

  20. Clinical outcomes of Ahmed glaucoma valve implantation in pediatric glaucoma.

    Science.gov (United States)

    Pakravan, Mohammad; Esfandiari, Hamed; Yazdani, Shahin; Doozandeh, Azadeh; Dastborhan, Zahra; Gerami, Ebrahim; Kheiri, Bahareh; Pakravan, Parastou; Yaseri, Mehdi; Hassanpour, Kiana

    2018-03-01

    To evaluate the outcomes of Ahmed glaucoma valve implantation in refractory primary congenital glaucoma as well as primary procedure in aphakic glaucoma. In this retrospective study, medical records of patients who underwent Ahmed glaucoma valve implantation for refractory glaucoma and aphakic glaucoma were reviewed. Primary outcome measures were the surgical success defined as intraocular pressure ≤21 mm Hg and decreased ≥20% and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity, and intraocular pressure. A total of 62 eyes of refractory primary congenital glaucoma patients (group 1) and 33 eyes of aphakic glaucoma patients (group 2) were included in our study. Mean follow-up was 51 ± 33 months in group 1 and 49 ± 41 months in group 2 (p = 0.82). The cumulative probability of success was 90% in both groups at the first year; however, the success rate was 52.5% in group 1 and 71.5% in group 2 at 5 years' follow-up visit. In group 1, the mean intraocular pressure ± standard deviation was 33.1 ± 8.6 mm Hg at the baseline and decreased to 17.1 ± 5.3 mm Hg at 1 year and 18.5 ± 6.4 at 3 years postoperatively (all p's glaucoma medications was 3 ± 0.7 that decreased to 2 ± 0.8 at final follow-up (p = 0.02). Ahmed glaucoma valve implantation has a moderate success rate in the management of refractory primary congenital glaucoma with an increased chance of tube-related complications. The surgical success rate is higher in case of primary Ahmed glaucoma valve implant for aphakic glaucoma with acceptable safety profile.

  1. Outcomes of percutaneous endoscopic gastrostomy tube insertion in respiratory impaired amyotrophic lateral sclerosis patients under noninvasive ventilation.

    Science.gov (United States)

    Czell, David; Bauer, Matthias; Binek, Janek; Schoch, Otto D; Weber, Markus

    2013-05-01

    Percutaneous endoscopic gastrostomy (PEG) tube placement in amyotrophic lateral sclerosis (ALS) patients with impaired respiratory function is associated with an increased risk of peri-procedural and post-interventional complications. It was the aim of the study to analyze peri- and post-interventional complications and survival after PEG tube placement under noninvasive ventilation (NIV) in ALS patients with various degrees of respiratory impairment. Twenty-six subjects were included in this retrospective case study. Prior to PEG tube placement, training with ventilatory support via an oronasal mask was performed with ALS subjects on the pneumology ward. PEG placement was then performed under continuous NIV. FVC, sniff nasal inspiratory pressure, and demographic data were assessed. Complication rates and 1-month and overall survival rates were analyzed. There were no deaths within 24 hours after PEG placement. One subject died within the first month. The mean survival rate after PEG was 12 ± 10 months (range 0.6-42 months). There was no difference in post-PEG survival between subjects with moderately (> 50%) and severely (NIV in ALS subjects.

  2. A Peer-Reviewed Instructional Video is as Effective as a Standard Recorded Didactic Lecture in Medical Trainees Performing Chest Tube Insertion: A Randomized Control Trial.

    Science.gov (United States)

    Saun, Tomas J; Odorizzi, Scott; Yeung, Celine; Johnson, Marjorie; Bandiera, Glen; Dev, Shelly P

    Online medical education resources are becoming an increasingly used modality and many studies have demonstrated their efficacy in procedural instruction. This study sought to determine whether a standardized online procedural video is as effective as a standard recorded didactic teaching session for chest tube insertion. A randomized control trial was conducted. Participants were taught how to insert a chest tube with either a recorded didactic teaching session, or a New England Journal of Medicine (NEJM) video. Participants filled out a questionnaire before and after performing the procedure on a cadaver, which was filmed and assessed by 2 blinded evaluators using a standardized tool. Western University, London, Ontario. Level of clinical care: institutional. A total of 30 fourth-year medical students from 2 graduating classes at the Schulich School of Medicine & Dentistry were screened for eligibility. Two students did not complete the study and were excluded. There were 13 students in the NEJM group, and 15 students in the didactic group. The NEJM group׳s average score was 45.2% (±9.56) on the prequestionnaire, 67.7% (±12.9) for the procedure, and 60.1% (±7.65) on the postquestionnaire. The didactic group׳s average score was 42.8% (±10.9) on the prequestionnaire, 73.7% (±9.90) for the procedure, and 46.5% (±7.46) on the postquestionnaire. There was no difference between the groups on the prequestionnaire (Δ + 2.4%; 95% CI: -5.16 to 9.99), or the procedure (Δ -6.0%; 95% CI: -14.6 to 2.65). The NEJM group had better scores on the postquestionnaire (Δ + 11.15%; 95% CI: 3.74-18.6). The NEJM video was as effective as video-recorded didactic training for teaching the knowledge and technical skills essential for chest tube insertion. Participants expressed high satisfaction with this modality. It may prove to be a helpful adjunct to standard instruction on the topic. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc

  3. Wound dehiscence and device migration after subconjunctival bevacizumab injection with Ahmed glaucoma valve implantation

    OpenAIRE

    Arezoo Miraftabi; Naveed Nilforushan

    2016-01-01

    Purpose: To report a complication pertaining to subconjunctival bevacizumab injection as an adjunct to Ahmed Glaucoma Valve (AGV) implantation. Case Report: A 54-year-old woman with history of complicated cataract surgery was referred for advanced intractable glaucoma. AGV implantation with adjunctive subconjunctival bevacizumab (1.25 mg) was performed with satisfactory results during the first postoperative week. However, 10 days after surgery, she developed wound dehiscence and tube exposur...

  4. [Quality of Life of Children with Otitis Media and Impact of Insertion of Transtympanic Ventilation Tubes in a Portuguese Population].

    Science.gov (United States)

    Lameiras, Ana Rita; Silva, Deodato; O Neill, Assunção; Escada, Pedro

    2018-01-31

    Quality of life is an important measure for health-outcome evaluation. Although otitis media is one of the most common childhood diseases, its impact on Portuguese children's quality of life is unknown. The aim of this study is to determine the quality of life of Portuguese children with chronic otitis media with effusion and/or recurrent acute otitis media and the short-term impact of transtympanic ventilation tubes, using the Portuguese version of the OM-6 questionnaire, a valid, reliable and sensitive instrument to evaluate the health-related quality of life in children with otitis media. This study was conducted in a tertiary referral center, to where children are referred from primary care and hospital pediatric consultations. The Portuguese version of the OM-6 questionnaire was applied to children with chronic otitis media with effusion and/or recurrent acute otitis media. The instrument was re-administered at two months postoperatively to a group of children who underwent tympanostomy tube placement, to evaluate the change in quality of life with the surgical procedure. The study involved a sample of 169 children, aged between 6 months and 12 years (mean: 4.20 ± 2.05 years). The average score in the survey was 3.3 ± 1.47, of a maximum of 7 (worst quality of life). The domains 'caregiver concerns', 'hearing loss' and 'physical suffering' had the highest scores. The domain 'hearing loss' was correlated with the domain 'speech impairment' (rs = 0.41; p Portuguese children quality of life. Tympanostomy tubes improve quality of life related to the middle ear in most children. The application of validated disease-specific questionnaires allows an enhanced understanding of the impact of otitis media on Portuguese children quality of life and of the success of therapeutic measures.

  5. Use of Autologous Scleral Graft in Ahmed Glaucoma Valve Surgery.

    Science.gov (United States)

    Wolf, Alvit; Hod, Yair; Buckman, Gila; Stein, Nili; Geyer, Orna

    2016-04-01

    To compare the efficacy of an autoscleral free-flap graft versus an autoscleral rotational flap graft in Ahmed glaucoma valve (AGV) surgery. Medical records (2005 to 2012) of 51 consecutive patients (51 eyes) who underwent AGV surgery with the use of either an autoscleral free-flap graft or an autoscleral rotational flap graft to cover the external tube at the limbus were retrieved for review. The main outcome measure was the incidence of tube exposure associated with each surgical approach. Twenty-seven consecutive patients (27 eyes) received a free-flap graft and 24 consecutive patients (24 eyes) received a rotational flap graft. The mean follow-up time was 55.6 ± 18.3 months for the former and 24.2± 5 .0 months for the latter (P<0.0001). Two patients in the free-flap group (8.9%) developed tube exposure at 24 and 55 months postoperatively compared with none of the patients in the rotational flap group. Graft thinning without evidence of conjunctival erosion was observed in 15 patients (55%) in the free-flap group and in 7 patients (29.1%) in the rotational flap group. The use of an autoscleral rotational flap graft is an efficacious technique for primary tube patch grafting in routine AGV surgery, and yielded better results than an autoscleral free-flap graft. Its main advantages over donor graft material are availability and lower cost.

  6. Endophthalmitis associated with the Ahmed glaucoma valve implant.

    Science.gov (United States)

    Al-Torbak, A A; Al-Shahwan, S; Al-Jadaan, I; Al-Hommadi, A; Edward, D P

    2005-04-01

    To investigate the rate, risk factors, clinical course, and treatment outcomes of endophthalmitis following glaucoma drainage implant (GDI) surgery. A computerised relational database search was conducted to identify all patients who were implanted with Ahmed glaucoma valve (AGV) and developed endophthalmitis following surgery at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, between 1 January 1994 and 30 November 2003. Only medical records of the patients who developed endophthalmitis were retrospectively reviewed. 542 eyes of 505 patients who were on active follow up were included in the study. Endophthalmitis developed in nine (1.7%) eyes; the rate was five times higher in children than in adults. Delayed endophthalmitis (developed 6 weeks after surgery) occurred in eight of nine eyes. Conjunctival erosion overlying the AGV tube was present in six of nine eyes. Common organisms isolated in the vitreous included Haemophilus influenzae and Streptococcus species. Multiple regression analysis revealed that younger age and conjunctival erosion over the tube were significant risk factors associated with endophthalmitis. Endophthalmitis is a rare complication of GDI surgery that appears to be more common in children. Conjunctival dehiscence over the GDI tube seems to represent a major risk factor for endophthalmitis. Prompt surgical revision of an exposed GDI tube is highly recommended.

  7. Endophthalmitis associated with the Ahmed glaucoma valve implant

    Science.gov (United States)

    Al-Torbak, A A; Al-Shahwan, S; Al-Jadaan, I; Al-Hommadi, A; Edward, D P

    2005-01-01

    Aim: To investigate the rate, risk factors, clinical course, and treatment outcomes of endophthalmitis following glaucoma drainage implant (GDI) surgery. Methods: A computerised relational database search was conducted to identify all patients who were implanted with Ahmed glaucoma valve (AGV) and developed endophthalmitis following surgery at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, between 1 January 1994 and 30 November 2003. Only medical records of the patients who developed endophthalmitis were retrospectively reviewed. Results: 542 eyes of 505 patients who were on active follow up were included in the study. Endophthalmitis developed in nine (1.7%) eyes; the rate was five times higher in children than in adults. Delayed endophthalmitis (developed 6 weeks after surgery) occurred in eight of nine eyes. Conjunctival erosion overlying the AGV tube was present in six of nine eyes. Common organisms isolated in the vitreous included Haemophilus influenzae and Streptococcus species. Multiple regression analysis revealed that younger age and conjunctival erosion over the tube were significant risk factors associated with endophthalmitis. Conclusion: Endophthalmitis is a rare complication of GDI surgery that appears to be more common in children. Conjunctival dehiscence over the GDI tube seems to represent a major risk factor for endophthalmitis. Prompt surgical revision of an exposed GDI tube is highly recommended. PMID:15774923

  8. A nationwide study on the impact of pneumococcal conjugate vaccination on antibiotic use and ventilation tube insertion in Denmark 2000-2014

    DEFF Research Database (Denmark)

    Howitz, Michael Frantz; Harboe, Zitta Barrella; Ingels, Helene

    2017-01-01

    Introduction of Pneumococcal Conjugated Vaccines (PCV) in national immunization programs have been successful in reducing the number of invasive and lower respiratory pneumococcal infections. The impact of the vaccines on upper respiratory infections caused by pneumococci is less clear although...... these account for most pneumococcal infections. In this study, we used likely proxies for respiratory infections in children, such as antibiotic use and ventilation tube insertions (VTI), to estimate the impact of the vaccine on a national level. The study was designed as a population-based retrospective...... reversed to near year 2000 levels after the introduction of PCV. This indicates that implementation of pneumococcal vaccines in the Childhood Vaccination Programme has likely reduced the incidence of upper respiratory diseases due to pneumococci in Denmark....

  9. Study on heat transfer and friction factor characteristics of γ-Al2O3/water through circular tube with twisted tape inserts with different thicknesses

    International Nuclear Information System (INIS)

    Esmaeilzadeh, E.; Almohammadi, H.; Nokhosteen, A.; Motezaker, A.; Omrani, A.N.

    2014-01-01

    An experimental study was carried out to investigate heat transfer and friction factor characteristics of γ-Al 2 O 3 /water nano-fluid through circular tube with twisted tape inserts with various thicknesses at constant heat flux. In this work, γ-Al 2 O 3 /water nano-fluids with two volume concentrations of 0.5% and 1% were used as the working fluid. The twist ratio of twisted tape remained constant at 3.21, while the thicknesses were changed through three values of 0.5 mm, 1 mm and 2 mm. The experiments were performed in laminar flow regime from 150 to 1600 Reynolds numbers. Results indicated that twisted tape inserts enhanced the average convective heat transfer coefficient, and also more the thickness of twisted tape is more the enhancement of convective heat transfer coefficient is. Also, the highest enhancement was achieved at maximum volume concentration. Results showed that nano-fluids have better heat transfer performance when utilized with thicker twisted tapes. At the same time, the increase in twisted tape thickness leads to an increase in friction factor. In the end, the combined results of these two phenomena result in enhanced convective heat transfer coefficient and thermal performance. Finally, two new correlations were offered for Nusselt number and thermal performance based on our experimental observation. (authors)

  10. Experience with the Ahmed Glaucoma Valve

    African Journals Online (AJOL)

    Design:Aprospective study of three glaucoma patients who had the Ahmed glaucoma valve implant at the. University of Benin ... Key words: glaucoma, glaucoma valve implant, ... introduced the micro-trephination with a diameter of. 0.6mm in ...

  11. To drain or not to drain? Predictors of tube thoracostomy insertion and outcomes associated with drainage of traumatic hemothoraces.

    Science.gov (United States)

    Wells, Bryan J; Roberts, Derek J; Grondin, Sean; Navsaria, Pradeep H; Kirkpatrick, Andrew W; Dunham, Michael B; Ball, Chad G

    2015-09-01

    Historical data suggests that many traumatic hemothoraces (HTX) can be managed expectantly without tube thoracostomy (TT) drainage. The purpose of this study was to identify predictors of TT, including whether the quantity of pleural blood predicted tube placement, and to evaluate outcomes associated with TT versus expected management (EM) of traumatic HTXs. A retrospective cohort study of all trauma patients with HTXs and an Injury Severity Score (ISS) ≥12 managed at a level I trauma centre between April 1, 2005 and December 31, 2012 was completed. Mixed-effects models with a subject-specific random intercept were used to identify independent risk factors for TT. Logistic and log-linear regression were used to compute odds ratios (ORs) for mortality and empyema and percent increases in length of hospital and intensive care unit stay between patients managed with TT versus EM, respectively. A total of 635 patients with 749 HTXs were included in the study. Overall, 491 (66%) HTXs were drained while 258 (34%) were managed expectantly. Independent predictors of TT placement included concomitant ipsilateral flail chest [OR 3.03; 95% confidence interval (CI) 1.04-8.80; p=0.04] or pneumothorax (OR 6.19; 95% CI 1.79-21.5; p<0.01) and the size of the HTX (OR per 10cc increase 1.12; 95% CI 1.04-1.21; p<0.01). Although the adjusted odds of mortality were not significantly different between groups (OR 3.99; 95% CI 0.87-18.30; p=0.08), TT was associated with a 47.14% (95% CI, 25.57-69.71%; p<0.01) adjusted increase in hospital length of stay. Empyemas (n=29) only occurred among TT patients. Expectant management of traumatic HTX was associated with a shorter length of hospital stay, no empyemas, and no increase in mortality. Although EM of smaller HTXs may be safe, these findings must be confirmed by a large multi-centre cohort study and randomized controlled trials before they are used to guide practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Tube plug

    International Nuclear Information System (INIS)

    Zafred, P. R.

    1985-01-01

    The tube plug comprises a one piece mechanical plug having one open end and one closed end which is capable of being inserted in a heat exchange tube and internally expanded into contact with the inside surface of the heat exchange tube for preventing flow of a coolant through the heat exchange tube. The tube plug also comprises a groove extending around the outside circumference thereof which has an elastomeric material disposed in the groove for enhancing the seal between the tube plug and the tube

  13. Clinical outcomes of Ahmed glaucoma valve in anterior chamber versus ciliary sulcus.

    Science.gov (United States)

    Bayer, A; Önol, M

    2017-04-01

    PurposeTo evaluate the outcomes of Ahmed glaucoma valve (AGV) tube insertion through the anterior chamber angle (ACA) or through the ciliary sulcus (CS).Patients and methodsIn this case-control study, we retrospectively reviewed the charts of consecutive glaucoma patients who had undergone AGV implantation either through the ACA or the CS between March 2009 and December 2014. The main outcome measures were intraocular pressure (IOP), number of glaucoma medications prescribed, best corrected visual acuity (BCVA), glaucoma type, success rate, complications, and survival ratios. Statistical analysis was carried out using SPSS.ResultsThere were 68 eyes in the ACA group and 35 eyes in the CS group. There were no significant differences between the groups for age, sex, laterality, IOP, preoperative glaucoma medication number, BCVA or glaucoma type (P>0.05). The postoperative follow-up period was 27.2±16.5 months and 30.2±17.7 months for the ACA and the CS groups (P=0.28); IOP values were significantly reduced at the last visit to 16.4±7.2 mm Hg and 14.4±6.8 mm Hg. The difference in the last-visit IOP between the groups was not significant (P=0.06), but the IOP reduction ratio was higher in the CS group (P=0.03). There was no significant difference in the number of postoperative medications (P=0.18). Postoperative complications were similar, but the incidence of flat anterior chamber was higher in the ACA group (P=0.05).ConclusionsThe use of an AGV can control IOP in the majority of cases whether placed in the ACA or the CS. The IOP reduction ratio seemed to be higher in the CS group.

  14. Otopathogens Detected in Middle Ear Fluid Obtained during Tympanostomy Tube Insertion: Contrasting Purulent and Non-Purulent Effusions

    Science.gov (United States)

    Holder, Robert C.; Kirse, Daniel J.; Evans, Adele K.; Whigham, Amy S.; Peters, Timothy R.; Poehling, Katherine A.; Swords, William E.; Reid, Sean D.

    2015-01-01

    Otitis media is a prominent disease among children. Previous literature indicates that otitis media is a polymicrobial disease, with Haemophilus influenzae, Streptococcus pneumoniae, Alloiococcus otitidis and Moraxella catarrhalis being the most commonly associated bacterial pathogens. Recent literature suggests that introduction of pneumococcal conjugate vaccines has had an effect on the etiology of otitis media. Using a multiplex PCR procedure, we sought to investigate the presence of the aforementioned bacterial pathogens in middle ear fluid collected from children undergoing routine tympanostomy tube placement at Wake Forest Baptist Medical Center during the period between January 2011 and March 2014. In purulent effusions, one or more bacterial organisms were detected in ~90% of samples. Most often the presence of H. influenzae alone was detected in purulent effusions (32%; 10 of 31). In non-purulent effusions, the most prevalent organism detected was A. otitidis (26%; 63 of 245). Half of the non-purulent effusions had none of these otopathogens detected. In purulent and non-purulent effusions, the overall presence of S. pneumoniae was lower (19%; 6 of 31, and 4%; 9 of 245, respectively) than that of the other pathogens being identified. The ratio of the percentage of each otopathogen identified in purulent vs. non-purulent effusions was >1 for the classic otopathogens but not for A. otitidis. PMID:26039250

  15. Nocardia brasiliensis endophthalmitis in a patient with an exposed Ahmed glaucoma drainage implant.

    Science.gov (United States)

    Stewart, Michael W; Bolling, James P; Bendel, Rick E

    2013-01-01

    To report a case of endophthalmitis due to Nocardia brasiliensis in an eye with an exposed, infected Ahmed glaucoma drainage implant (GDI). Retrospective case report. A patient with an exposed GDI experienced recurrent episodes of endophthalmitis despite repeated intravitreal injections of antibiotics and steroids. The tube was initially repositioned and finally removed. Whereas repeated cultures from the anterior chamber and vitreous were negative, cultures from the removed tube grew Nocardia brasiliensis. Despite oral trimethoprim-sulfamethoxazole and intravitreal amikacin the eye became phthisical and lost light perception. An exposed GDI may lead to endophthalmitis due to Nocardia brasiliensis and may require explantation to establish a diagnosis.

  16. Ab interno management of blocked Ahmed valve in the posterior segment.

    Science.gov (United States)

    Odrich, Steven; Wald, Kenneth; Sperber, Laurence

    2013-01-01

    To report a case of late failure of a posterior segment placed Ahmed valve in a uveitic eye with a corneal graft and a minimally invasive, ab interno approach in restoring valve function, pressure control, and preservation of vision. Case report. A 25 gauge trans-conjunctival 3-port pars plana vitrectomy was performed to inspect and clean the ostium of the Ahmed valve of any vitreous debris. The Ahmed valve was not disturbed externally and conjunctival dissection was not performed. A 27-gauge blunt cannula was introduced through the vitrector site and used to cannulate the tube and flush it with balanced salt solution. A bleb was immediately re-established and all instruments were removed requiring no sutures. Intraocular pressure returned to target levels and a filtration bleb was re-established. Corneal graft clarity was restored with resolution of preoperative microcystic edema. Postoperative inflammation was minimal and vision was restored. A nonfunctioning tube shunt residing in the vitreous cavity may be revised ab interno without disturbing the shunt placement or the conjunctiva under which it resides to re-establish filtration.

  17. Sutureless human sclera donor patch graft for Ahmed glaucoma valve.

    Science.gov (United States)

    Zeppa, Lucio; Romano, Mario R; Capasso, Luigi; Tortori, Achille; Majorana, Mara A; Costagliola, Ciro

    2010-01-01

    To report the safety and effectiveness of a sutureless human sclera donor patch graft covering the subconjunctival portion of glaucoma drainage implant tube to prevent its erosion throughout the overlying conjunctiva. This was a prospective pilot study. Fifteen eyes of 15 consecutive patients not responsive to medical and to not-implant surgical glaucoma treatment underwent Ahmed glaucoma valve (AGV) implant surgery with sutureless human sclera donor patch graft. The surgical procedure included AVG implant placed 8 mm behind the corneal limbus and fixed to the sclera with two 9-0 black nylon sutures. The tube was passed through the scleral tunnel, parallel to the corneal limbus, and shortened at the desired length. The anterior part of the tube was covered with human donor scleral graft and kept in place with fibrin glue (Tissue Coll) under the conjunctiva. Examinations were scheduled at baseline and then at 1 week and 1, 3, 6, and 12 months after surgery. At 12-month follow-up, the best-corrected visual acuity did not significantly improve from baseline 0.78+/-1.2 logMAR, whereas mean intraocular pressure significantly decreased from preoperative values of 29.8 (SD 8.4) mmHg. In all cases, the scleral patch was found in place at each check during the follow-up period. No conjunctival erosion over the AGV tube nor sign of endophthalmitis was recorded at any time during the follow-up period. AVG implant surgery with sutureless human sclera donor patch graft represents an effective and relatively safe surgical procedure for complicated glaucomas, avoiding conjunctival erosions over the AGV tube.

  18. Ahmed Glaucoma Valve Implantation in Vitrectomized Eyes

    OpenAIRE

    Erçalık, Nimet Yeşim; İmamoğlu, Serhat

    2018-01-01

    Purpose. To evaluate the outcomes of Ahmed glaucoma valve (AGV) implantation in vitrectomized eyes. Materials and Methods. The medical records of 13 eyes that developed glaucoma due to emulsified silicon oil or neovascularization following pars plana vitrectomy and underwent AGV implantation were retrospectively reviewed. The main outcome measures were intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of antiglaucoma medications, and postoperative complications. Surgical...

  19. Performance Study of a Cylindrical Parabolic Concentrating Solar Water Heater with Nail Type Twisted Tape Inserts in the Copper Absorber Tube

    Directory of Open Access Journals (Sweden)

    Amit K. Bhakta

    2018-01-01

    Full Text Available This paper reports the overall thermal performance of a cylindrical parabolic concentrating solar water heater (CPCSWH with inserting nail type twisted tape (NTT in the copper absorber tube for the nail twist pitch ratios, 4.787, 6.914 and 9.042, respectively. The experiments are conducted for a constant volumetric water flow rate and during the time period 9:00 a.m. to 15:00 p.m. The useful heat gain, hourly solar energy collected and hourly solar energy stored in this solar water heater were found to be higher for the nail twist pitch ratio 4.787. The above said parameters were found to be at a peak at noon and observed to follow the path of variation of solar intensity. At the start of the experiment, the value of charging efficiency was observed to be maximum, whereas the maximum values of instantaneous efficiency and overall thermal efficiency were observed at noon. The key finding is that the nail twist pitch ratio enhances the overall thermal performance of the CPCSWH.

  20. Measurement of impulse peak insertion loss from two acoustic test fixtures and four hearing protector conditions with an acoustic shock tube

    Science.gov (United States)

    Murphy, William J.; Fackler, Cameron J.; Berger, Elliott H.; Shaw, Peter B.; Stergar, Mike

    2015-01-01

    Impulse peak insertion loss (IPIL) was studied with two acoustic test fixtures and four hearing protector conditions at the E-A-RCAL Laboratory. IPIL is the difference between the maximum estimated pressure for the open-ear condition and the maximum pressure measured when a hearing protector is placed on an acoustic test fixture (ATF). Two models of an ATF manufactured by the French-German Research Institute of Saint-Louis (ISL) were evaluated with high-level acoustic impulses created by an acoustic shock tube at levels of 134 decibels (dB), 150 dB, and 168 dB. The fixtures were identical except that the E-A-RCAL ISL fixture had ear canals that were 3 mm longer than the National Institute for Occupational Safety and Health (NIOSH) ISL fixture. Four hearing protection conditions were tested: Combat Arms earplug with the valve open, ETYPlugs® earplug, TacticalPro headset, and a dual-protector ETYPlugs earplug with TacticalPro earmuff. The IPILs measured for the E-A-RCAL fixture were 1.4 dB greater than the National Institute for Occupational Safety and Health (NIOSH) ISL ATF. For the E-A-RCAL ISL ATF, the left ear IPIL was 2.0 dB greater than the right ear IPIL. For the NIOSH ATF, the right ear IPIL was 0.3 dB greater than the left ear IPIL. PMID:26356380

  1. Conductive sub-layer of twisted-tape-induced swirl-flow heat transfer in vertical circular tubes with various twisted-tape inserts

    Science.gov (United States)

    Hata, K.; Fukuda, K.; Masuzaki, S.

    2018-04-01

    conductive sub-layer δ CSL and the nondimensional thickness of the conductive sub-layer y + CSL on the circular tubes with various twisted-tape inserts were determined on the basis of numerical solutions for the swirl velocities u sw ranging from 5.23 to 21.18 m/s. Correlations between the conductive sub-layer thickness δ CSL and the nondimensional thickness of the conductive sub-layer y + CSL for twisted-tape-induced swirl-flow heat transfer in a vertical circular tube were derived.

  2. Where's the line/tube? | Ahmed | SA Journal of Radiology

    African Journals Online (AJOL)

    Radiologists are confronted with a spectrum of catheters placed in various locations in routine radiology practice and have to be familiar with the different catheters, their uses and acceptable positioning for suggested safe practice. The commonly used vascular and nonvascular catheters are described and discussed in this ...

  3. Testing of self-repairing composite airplane components by use of CAI and the release of the repair chemicals from carefully inserted small tubes

    Science.gov (United States)

    Dry, Carolyn

    2007-04-01

    The research on self repair of airplane components, under an SBIR phase II with Wright Patterson Air Force Base, has investigated the attributes and best end use applications for such a technology. These attributes include issues related to manufacturability, cost, potential benefits such as weight reduction, and cost reduction. The goal of our research has been to develop self-repairing composites with unique strength for air vehicles. Our revolutionary approach involves the autonomous release of repair chemicals from within the composite matrix itself. The repair agents are contained in hollow, structural fibers that are embedded within the matrix. Under stress, the composite senses external environmental factors and reacts by releasing the repair agents from within the hollow vessels. This autonomous response occurs wherever and whenever cracking, debonding or other matrix damage transpires. Superior performance over the life of the composite is achieved through this self-repairing mechanism. The advantages to the military would be safely executed missions, fewer repairs and eventually lighter vehicles. In particular the research has addressed the issues by correlating the impact of the various factors, such as 1) delivery vessel placement, shape/size and effect on composite strength, chemicals released and their effect on the matrix, release trigger and efficacy and any impact on matrix properties 2) impact of composite processing methods that involve heat and pressure on the repair vessels. Our self repairing system can be processed at temperatures of 300-350F, repairs in less than 30 seconds and does not damage the composite by repair fiber insertion or chemical release. Scaling up and manufacture of components has revealed that anticipating potential problems allowed us to avoid those associated with processing temperatures and pressures. The presentation will focus on compression after impact testing and the placement of repair fibers/tubes into prepreg

  4. Managing high risk glaucoma with the Ahmed valve implant: 20 years of experience.

    Science.gov (United States)

    Rotsos, Tryfon; Tsioga, Anastasia; Andreanos, Konstantinos; Diagourtas, Andreas; Petrou, Petros; Georgalas, Ilias; Papaconstantinou, Dimitrios

    2018-01-01

    To estimate the efficacy and safety of the Ahmed implant in patients with high risk for failure after glaucoma surgery. In 342 eyes of 342 patients with refractory glaucoma, even with application of medical treatment, the Ahmed valve was introduced for intraocular pressure (IOP) control, in the period of the last 20y. The nature of glaucoma was neovascular in 162 eyes, pseudophakic or aphakic in 49 eyes, inflammatory in 29 eyes and non working previous antiglaucomatic surgical interventions in 102 eyes. Follow-up ranged from 18 to 120mo with a mean follow-up of 63.2mo. IOP before the operation decreased from 31.6±10.4 mm Hg to 18.3±5.4 mm Hg (no systemic treatment) at the end of follow up period. When we compared the IOP values before the operation using ANOVA showed statistically significant difference ( P glaucoma, 63.2% in aphakic glaucoma and 73.8% in non working previous antiglaucomatic surgical interventions. Complications due to the implant were: serous choroidal detachment in 14.8%, blockage of the tube in 2.8%, malposition of the tube in 4.9%, suprachoroidal hemorrhage in 2.1%, cataract progression in 39.6% (phakic eyes), shallow anterior chamber in 9.2%, hyphaema in 28.9%, exposure of valve in 2.6%, exposure of tube in 9.3%, hypotony in 4.9% and conjunctival fibrosis in 41.5%. Despite the fact that Ahmed valve implant had suchlike results as other implants concerning the IOP control, complications rate due to hypotony or over filtration in the first days after the intervention are not that frequent as with other valve implants.

  5. Effect of kinetic parameters on simultaneous ramp reactivity insertion plus beam tube flooding accident in a typical low enriched U{sub 3}Si{sub 2}-Al fuel-based material testing reactor-type research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nasir, Rubina; Mirza, Nasir M. [Dept. of, Physics, Air University, Islamabad (Pakistan); Mirza, Sikander M. [Dept. of, Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, Post Office Nilore, Islamabad (Pakistan)

    2017-06-15

    This work looks at the effect of changes in kinetic parameters on simultaneous reactivity insertions and beam tube flooding in a typical material testing reactor-type research reactor with low enriched high density (U{sub 3}Si{sub 2}-Al) fuel. Using a modified PARET code, various ramp reactivity insertions (from $0.1/0.5 s to $1.3/0.5 s) plus beam tube flooding ($0.5/0.25 s) accidents under uncontrolled conditions were analyzed to find their effects on peak power, net reactivity, and temperature. Then, the effects of changes in kinetic parameters including the Doppler coefficient, prompt neutron lifetime, and delayed neutron fractions on simultaneous reactivity insertion and beam tube flooding accidents were analyzed. Results show that the power peak values are significantly sensitive to the Doppler coefficient of the system in coupled accidents. The material testing reactor-type system under such a coupled accident is not very sensitive to changes in the prompt neutron life time; the core under such a coupled transient is not very sensitive to changes in the effective delayed neutron fraction.

  6. The use of Ahmed glaucoma valve in the management of pediatric glaucoma.

    Science.gov (United States)

    Balekudaru, Shantha; Vadalkar, Juhie; George, Ronnie; Vijaya, Lingam

    2014-08-01

    To assess the intraocular pressure control (IOP), changes in visual acuity, complications, reoperation rates and risk factors for failure following Ahmed glaucoma valve implantation in pediatric eyes with glaucoma. The medical records of consecutive patients with glaucoma who underwent Ahmed glaucoma valve implantation from January 2000 to December 2009) were retrospectively reviewed. Only one eye of each patient was included. Subgroup analysis was performed in three groups; group 1 included phakic eyes with primary congenital glaucoma, juvenile open-angle glaucoma, or glaucoma associated with ocular anomalies; group 2 included eyes with glaucoma in aphakia or pseudophakia; group 3 included eyes with other diagnoses. A successful outcome was defined as final IOP between 6 mm Hg and 18 mm Hg without loss of light perception or reoperation for glaucoma. A total of 71 eyes in 71 patients: 15 (21%) in group 1, 47 (66%) in group 2, and 9 (13%) in group 3 were included Successful IOP control was achieved in 44 eyes of 44 patients (62%). Cumulative probabilities of success by Kaplan-Meier analysis at 12 and 24 months was 97% and 80% for the entire group, 100% and 82% for group 1, 95% and 86% for group 2, and 90% and 42% for group 3. Reoperation was necessary for 18 patients (25%), either for tube-related complications or for IOP control. The only significant risk factor for failure was the category of diagnosis (P = 0.029). Ahmed glaucoma valve implantation is an option in the management of pediatric glaucoma; however, reoperations for tube related complications or for persistent elevated IOP is frequently needed. Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  7. [Long-term outcomes of Ahmed glaucoma valve implantation for treating refractory glaucoma].

    Science.gov (United States)

    Xu, Yumei; Hong, Tao; Li, Wanming

    2015-02-10

    To explore the efficacies and complications of Ahmed glaucoma valve implantation for treating refractory glaucoma. A retrospective study of case series was conducted for 24 patients (26 eyes) with refractory glaucoma from February 2001 to July 2008 at our hospital. Ahmed glaucoma valve implantation was performed. Pre- and post-operative best spectacle-corrected visual acuity (BSCVA), intraocular pressure (IOP), number of medications and complications were recorded and analyzed. The follow-up period was 58-159 months. The post-operative values of IOP were 13.02+/-6.79, 11.43+/-5.24 and 18.56+/-6.43 mmHg at 1 day, 1 month and the last follow-up respectively. There were significant difference when compared with pre-operative IOP (37.59+/-10.76 mmHg, P glaucoma drugs after glaucoma valve implantation and the average number of medication was 1.72+/-0.98. There was significant difference with the pre-operative medication number 2.7 ± 0.7 (P = 0.001). The surgical success rate was 73.1%. And the causes of failure were endophthalmitis, corneal endothelial decompensation, persistent conjunctival wound non-healing, glaucoma valve exposure and loss of light perception.Early postoperative complications were ocular hypotony, shallow anterior chamber, hyphema, transient high IOP and tube occlusion. And long-term complications included encapsulated cyst formation, tube exposure, corneal endothelial decompensation and endophthalmitis. Ahmed glaucoma valve implantation is efficacious for refractory glaucoma.However, clinicians should pay attention to the prevention and treatment of complications.

  8. An experimental investigation on heat transfer enhancement in the laminar flow of water/TiO2 nanofluid through a tube heat exchanger fitted with modified butterfly inserts

    Science.gov (United States)

    Venkitaraj, K. P.; Suresh, S.; Alwin Mathew, T.; Bibin, B. S.; Abraham, Jisa

    2018-03-01

    Nanofluids are advanced heat transfer fluids that exhibit thermal properties superior than that of the conventional fluids such as water, oil etc. This paper reports the experimental study on convective heat transfer characteristics of water based titanium dioxide nanofluids in fully developed flow through a uniformly heated pipe heat exchanger fitted with modified butterfly inserts. Nanofluids are prepared by dispersing TiO2 nanoparticles of average particle size 29 nm in deionized water. The heat transfer experiments are performed in laminar regime using nanofluids prepared with 0.1% and 0.3% volume fractions of TiO2 nanoparticles. The thermal performance characteristics of conventional butterfly inserts and modified butterfly inserts are also compared using TiO2 nanofluid. The inserts with different pitches 6 cm, 9 cm and 12 cm are tested to determine the effect of pitch distance of inserts in the heat transfer and friction. The experimental results showed that the modification made in the butterfly inserts were able to produce higher heat transfer than conventional butterfly inserts.

  9. The Ahmed Versus Baerveldt Study: Five-Year Treatment Outcomes.

    Science.gov (United States)

    Christakis, Panos G; Kalenak, Jeffrey W; Tsai, James C; Zurakowski, David; Kammer, Jeffrey A; Harasymowycz, Paul J; Mura, Juan J; Cantor, Louis B; Ahmed, Iqbal I K

    2016-10-01

    To compare 2 frequently used aqueous shunts for the treatment of glaucoma. International, multicenter, randomized trial. Patients aged 18 years or older with uncontrolled glaucoma despite maximum tolerated medical therapy, many of whom had failed or were at high risk of failing trabeculectomy. Eligible patients were randomized to receive an Ahmed-FP7 valve implant (New World Medical, Inc, Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc, Santa Ana, CA) using a standardized surgical technique. The primary outcome was failure, defined as intraocular pressure (IOP) outside the target range (5-18 mmHg) or reduced glaucoma surgery. Secondary outcomes measures included IOP, medication use, visual acuity, complications, and interventions. A total of 238 patients were randomized; 124 received the Ahmed-FP7 implant, and 114 received the Baerveldt-350 implant. Baseline characteristics were similar between groups. Mean preoperative IOP was 31.4±10.8 mmHg on 3.1±1.0 glaucoma medications. At 5 years, the cumulative failure rate was 53% in the Ahmed group and 40% in the Baerveldt group (P = 0.04). The main reason for failure in both groups was high IOP, and the cumulative de novo glaucoma reoperation rate was 18% in the Ahmed group and 11% in the Baerveldt group (P = 0.22). Hypotony resulted in failure in 5 patients (4%) in the Baerveldt group compared with none in the Ahmed group (P = 0.02). Mean IOP was 16.6±5.9 mmHg in the Ahmed group (47% reduction) and 13.6±5.0 mmHg in the Baerveldt group (57% reduction, P = 0.001). Mean medication use was 1.8±1.5 mmHg in the Ahmed group (44% reduction) and 1.2±1.3 mmHg in the Baerveldt group (61% reduction, P = 0.03). The 2 groups had similar complication rates (Ahmed 63%, Baerveldt 69%) and intervention rates (Ahmed 41%, Baerveldt 41%). Most complications were transient, and most interventions were slit-lamp procedures. Both implants were effective in reducing IOP and the need for glaucoma

  10. Wound Dehiscence and Device Migration after Subconjunctival Bevacizumab Injection with Ahmed Glaucoma Valve Implantation.

    Science.gov (United States)

    Miraftabi, Arezoo; Nilforushan, Naveed

    2016-01-01

    To report a complication pertaining to subconjunctival bevacizumab injection as an adjunct to Ahmed Glaucoma Valve (AGV) implantation. A 54-year-old woman with history of complicated cataract surgery was referred for advanced intractable glaucoma. AGV implantation with adjunctive subconjunctival bevacizumab (1.25 mg) was performed with satisfactory results during the first postoperative week. However, 10 days after surgery, she developed wound dehiscence and tube exposure. The second case was a 33-year-old man with history of congenital glaucoma and uncontrolled IOP who developed AGV exposure and wound dehiscence after surgery. In both cases, for prevention of endophthalmitis and corneal damage by the unstable tube, the shunt was removed and the conjunctiva was re-sutured. The potential adverse effect of subconjunctival bevacizumab injection on wound healing should be considered in AGV surgery.

  11. Trabeculectomy versus Ahmed Glaucoma Valve implantation in neovascular glaucoma

    Science.gov (United States)

    Shen, Christopher C; Salim, Sarwat; Du, Haiming; Netland, Peter A

    2011-01-01

    Purpose: To compare surgical outcomes in neovascular glaucoma patients who underwent trabeculectomy with mitomycin C versus Ahmed Glaucoma Valve implantation. Patients and methods: This was a retrospective comparative case series. We reviewed 40 eyes of 39 patients with underlying diagnosis of neovascular glaucoma, divided into two groups: Ahmed Glaucoma Valve (N = 20) and trabeculectomy with mitomycin C (N = 20). Surgical success was defined as 6 mm Hg ≤ intraocular pressure ≤21 mm Hg, with or without the use of glaucoma medications, with no further glaucoma surgery, and light perception or better vision. Early postoperative hypotony was defined as intraocular pressure Ahmed Glaucoma Valve group and 25 months (6–77 months) for the trabeculectomy group. Although the mean number of postoperative intraocular pressure-lowering medications was significantly higher in the trabeculectomy group compared with the Ahmed Glaucoma Valve group at 3 and 6 month time points, there was no statistically significant difference at any other time point. There was no statistically significant difference between both groups in postoperative visual acuity and intraocular pressure. Success was 70% and 65% at 1 year and 60% and 55% at 2 years after Ahmed Glaucoma Valve and trabeculectomy, respectively. Kaplan–Meier survival curve analysis showed no significant difference in success between the two groups (P = 0.815). Hyphema was the most common complication in both groups. Conclusion: We found similar results after trabeculectomy with mitomycin C and Ahmed Glaucoma Valve implantation in eyes with neovascular glaucoma. PMID:21468334

  12. Five-Year Pooled Data Analysis of the Ahmed Baerveldt Comparison Study and the Ahmed Versus Baerveldt Study.

    Science.gov (United States)

    Christakis, Panos G; Zhang, Dongyu; Budenz, Donald L; Barton, Keith; Tsai, James C; Ahmed, Iqbal I K

    2017-04-01

    To determine the relative efficacy of the Ahmed-FP7 and Baerveldt BG101-350 implants. Pooled analysis of 2 multicenter, randomized clinical trials. A total of 514 patients aged 18 or older with uncontrolled glaucoma that had failed or were at high risk of failing trabeculectomy were randomized to receive an Ahmed implant (n = 267) or Baerveldt implant (n = 247). Cumulative failure rates (using an intraocular pressure [IOP] target of 6-18 mm Hg inclusive), de novo glaucoma surgery rates, mean IOP, mean glaucoma medication use, and visual acuity were compared. Baseline characteristics were similar between groups. Mean preoperative IOP of the study population was 31.5 ± 11.3 mm Hg on an average of 3.3 ± 1.1 glaucoma medications. At 5 years, mean IOP was 15.8 ± 5.2 mm Hg in the Ahmed group and 13.2 ± 4.7 mm Hg in the Baerveldt group (P glaucoma medication use was 1.9 ± 1.5 in the Ahmed group and 1.5 ± 1.4 in the Baerveldt group (P = .007). The cumulative failure rate at 5 years was 49% in the Ahmed group and 37% in the Baerveldt group (P = .007). High IOP was the most common reason for failure in both groups, and de novo glaucoma surgery was required in 16% of the Ahmed group and 8% of the Baerveldt group (P = .006). Failure owing to hypotony occurred in 0.4% of the Ahmed group and 4.5% of the Baerveldt group (P = .002). Visual outcomes were similar between groups (P = .90). The Baerveldt group had a lower failure rate, lower rate of de novo glaucoma surgery, and lower mean IOP on fewer medications than the Ahmed group. Baerveldt implantation carried a higher risk of hypotony. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The rendezvous technique involving insertion of a guidewire in a percutaneous transhepatic gallbladder drainage tube for biliary access in a case of difficult biliary cannulation.

    Science.gov (United States)

    Sunada, Fumiko; Morimoto, Naoki; Tsukui, Mamiko; Kurata, Hidekazu

    2017-05-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic method and treatment approach for biliary diseases. However, biliary cannulation can be difficult in some cases. We performed ERCP in a 97-year-old woman with abdominal pain resulting from acute cholangitis caused by choledocholithiasis and observed difficult biliary cannulation. Eventually, the patient was successfully treated with the rendezvous technique. We could not cannulate the biliary duct during ERCP twice. Therefore, we placed a percutaneous transhepatic gallbladder drainage (PTGBD) tube without intrahepatic dilation. The rendezvous technique was performed using the PTGBD tube. The patient did not experience pancreatitis or perforation.

  14. Bleb incarceration following Ahmed valve surgery

    Directory of Open Access Journals (Sweden)

    Gross FJ

    2016-10-01

    Full Text Available Fredric J Gross, Giovanni DiSandro Department of Ophthalmology, Eastern Virginia Medical School, Norfolk, VA, USA Abstract: Globe luxation is a painful and potentially vision-threatening condition in which the globe becomes trapped behind the eyelids requiring physician intervention in the emergency department or eye clinic. On presentation, the patient typically complains of an inability to close their eye, severe foreign body sensation, decreased vision, and significant eye pain. Although most visual symptoms are reversible and primarily result from exposure keratopathy, optic nerve damage, and permanent vision loss can occur from repeat or prolonged episodes of globe luxation. Risk factors include any congenital or acquired conditions that displace the globe anteriorly in the orbit and increased eyelid laxity that allows the globe to prolapse through the lid aperture. Typically, the precipitating event involves eyelid retraction during ophthalmic examination or an event that increases intraorbital pressure such as coughing or sneezing. Once the globe has luxated, the condition is typically worsened by blepharospasm and patients’ attempts to close the eye that worsen the entrapment. In the current case, the patient had a large superotemporal filtering bleb following Ahmed valve surgery for uncontrolled glaucoma. While instilling her glaucoma medication, she retracted her eyelids sufficiently to pull the upper lid over her filtering bleb where it became entrapped causing a similar presentation to globe luxation. Traditional methods of repositioning the globe were unsuccessful. Bleb needling was ultimately required to return the globe to a normal position. Keywords: luxation, globe, glaucoma

  15. The use of irradiated corneal patch grafts in pediatric Ahmed drainage implant surgery.

    Science.gov (United States)

    Nolan, Kaitlyn Wallace; Lucas, Jordyn; Abbasian, Javaneh

    2015-10-01

    To describe the use of irradiated cornea for scleral reinforcement in Ahmed glaucoma valve drainage implant (AGV) devices in children. The medical records of patients endophthalmitis, and tube/plate self-explantation. A total of 25 procedures (20 patients) met inclusion criteria. Average patient age was 70 months (range, 2 months to 17 years). Mean follow-up was 24.8 months (range, 6 months to 6.2 years). One tube experienced conjunctival exposure through two separate corneal grafts (2/25 cases [8%]), sequentially in the same eye. The first event occurred at month 3.5 after primary implantation of the tube shunt; the second erosion occurred following revision of the existing implant at month 1.5 postoperatively. There were 2 cases of auto-explantation, 2 cases of wound dehiscence, and 1 case of persistent inflammation. There were no cases of endophthalmitis or other infections. To our knowledge, this is the first report describing the use of corneal patch grafts in children. Irradiated cornea improves cosmesis and enhances visualization of the tube. The risk of tube exposure was found to be low and comparable to other materials used as a patch graft. Copyright © 2015 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  16. Limitations of Routine Verification of Nasogastric Tube Insertion Using X-Ray and Auscultation: Two Case Reports of Life-Threatening Complications.

    Science.gov (United States)

    Nejo, Takahide; Oya, Soichi; Tsukasa, Tsuchiya; Yamaguchi, Naomi; Matsui, Toru

    2016-12-01

    Several bedside approaches used in combination with thoracoabdominal X-ray are widely used to avoid severe complications that have been reported during nasogastric tube management. Although confirmation by X-ray is considered the gold standard, it is not yet perfect. We present 2 cases of rare complications in which the routine verification methods could not detect all the complications related to the nasogastric tube placement. Case 1 was a 17-year-old male who presented with a brain tumor and repeatedly required nasogastric tube placement. Despite normal auscultatory and X-ray findings, the patient's condition deteriorated rapidly after resuming the enteral nutrition (EN). Computed tomography images showed the presence of hepatic portal venous gas (HPVG). Urgent upper gastrointestinal endoscopy showed esophagogastric submucosal tunneling of the tube that required an emergency open total gastrectomy. Case 2 was a 76-year-old man with long-term EN after stroke. While the last auscultatory verification was normal, he suddenly developed extensive HPVG due to gastric mucosal injury following EN, which resulted in progressive intestinal necrosis, general peritonitis, and death. These 2 cases indicated that routine verification methods consisting of auscultation and X-ray may not be completely reliable, and the awareness of the limitations of these methods should be reaffirmed because expeditious examinations and necessary interventions are critical in preventing life-threatening complications.

  17. The Ahmed Versus Baerveldt study: one-year treatment outcomes.

    Science.gov (United States)

    Christakis, Panos G; Kalenak, Jeffrey W; Zurakowski, David; Tsai, James C; Kammer, Jeffrey A; Harasymowycz, Paul J; Ahmed, Iqbal I K

    2011-11-01

    To report the 1-year treatment outcomes of the Ahmed Versus Baerveldt (AVB) Study. Multicenter randomized clinical trial. A total of 238 patients were enrolled in the study, including 124 in the Ahmed group and 114 in the Baerveldt group. Patients aged 18 years or older with uncontrolled glaucoma refractory to medicinal, laser, and surgical therapy were randomized to undergo implantation of an Ahmed-FP7 valve (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA), to be followed for 5 years. The primary outcome measure was failure, defined as intraocular pressure (IOP) out of target range (5-18 mmHg with ≥ 20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, additional glaucoma procedures, or loss of light perception. Secondary outcome measures included IOP, medication use, visual acuity, complications, and interventions. There were no significant differences in baseline ocular or demographic characteristics between the study groups with the exception of sex. Preoperatively, the study group had a mean IOP of 31.4 ± 10.8 mmHg on a mean of 3.1 ± 1.0 glaucoma medications with a median Snellen acuity of 20/100. The cumulative probability of failure a 1-year was 43% in the Ahmed group and 28% in the Baerveldt group (P = 0.02). The mean IOP at 1 year was 16.5 ± 5.3 mmHg in the Ahmed group and 13.6 ± 4.8 mmHg in the Baerveldt group (P glaucoma medications required was 1.6 ± 1.3 in the Ahmed group and 1.2 ± 1.3 in the Baerveldt group (P = 0.03). Visual acuity was similar in both groups at all visits in the first year (P = 0.66). In the first year after surgery, there were a similar number of patients who experienced postoperative complications in the 2 groups (45% Ahmed, 54% Baerveldt, P = 0.19), but a greater number of patients in the Baerveldt group required interventions (26% Ahmed vs. 42% Baerveldt, P = 0.009). The Baerveldt-350 group had a higher

  18. Managing high risk glaucoma with the Ahmed valve implant: 20 years of experience

    Directory of Open Access Journals (Sweden)

    Tryfon Rotsos

    2018-02-01

    Full Text Available AIM: To estimate the efficacy and safety of the Ahmed implant in patients with high risk for failure after glaucoma surgery. METHODS: In 342 eyes of 342 patients with refractory glaucoma, even with application of medical treatment, the Ahmed valve was introduced for intraocular pressure (IOP control, in the period of the last 20y. The nature of glaucoma was neovascular in 162 eyes, pseudophakic or aphakic in 49 eyes, inflammatory in 29 eyes and non working previous antiglaucomatic surgical interventions in 102 eyes. RESULTS: Follow-up ranged from 18 to 120mo with a mean follow-up of 63.2mo. IOP before the operation decreased from 31.6±10.4 mm Hg to 18.3±5.4 mm Hg (no systemic treatment at the end of follow up period. When we compared the IOP values before the operation using ANOVA showed statistically significant difference (P<0.001. The success rate was 85.2% during the first semester, 76.8% at 12mo and 50.3% at the end of follow up period (18 to 120mo after implantation. Success rate was 25.7% in neovascular glaucoma, 63.2% in aphakic glaucoma and 73.8% in non working previous antiglaucomatic surgical interventions. Complications due to the implant were: serous choroidal detachment in 14.8%, blockage of the tube in 2.8%, malposition of the tube in 4.9%, suprachoroidal hemorrhage in 2.1%, cataract progression in 39.6% (phakic eyes, shallow anterior chamber in 9.2%, hyphaema in 28.9%, exposure of valve in 2.6%, exposure of tube in 9.3%, hypotony in 4.9% and conjunctival fibrosis in 41.5%. CONCLUSION: Despite the fact that Ahmed valve implant had suchlike results as other implants concerning the IOP control, complications rate due to hypotony or over filtration in the first days after the intervention are not that frequent as with other valve implants.

  19. Ahmed Glaucoma Valve Implantation in Vitrectomized Eyes

    Directory of Open Access Journals (Sweden)

    Nimet Yeşim Erçalık

    2018-01-01

    Full Text Available Purpose. To evaluate the outcomes of Ahmed glaucoma valve (AGV implantation in vitrectomized eyes. Materials and Methods. The medical records of 13 eyes that developed glaucoma due to emulsified silicon oil or neovascularization following pars plana vitrectomy and underwent AGV implantation were retrospectively reviewed. The main outcome measures were intraocular pressure (IOP, best-corrected visual acuity (BCVA, number of antiglaucoma medications, and postoperative complications. Surgical success was defined as last IOP ≤21 mmHg or ≥6 mmHg and without loss of light perception. Results. The mean follow-up duration was 11.7 ± 5.5 (range, 6–23 months. The mean IOP before the AGV implantation was 37.9 ± 6.7 mmHg with an average of 3.5 ± 1.2 drugs. At the final visit, the mean IOP was 15.9 ± 4.6 mmHg (p=0.001 and the mean number of glaucoma medications decreased to 2.3 ± 1.3 (p=0.021. At the last visit, 11 eyes (84.4% had stable or improved VA and one eye (7.7% had a final VA of no light perception. Surgical success was achieved in 11 of the 13 eyes (84.4%. Postoperative complications were bleb encapsulation (69.2%, early hypotony (38.5%, hyphema (23.1%, decompression retinopathy (23.1%, choroidal detachment (15.4%, intraocular hemorrhage (7.7%, and late endophthalmitis (7.7%. One eye (7.7% was enucleated because of late endophthalmitis. Conclusions. Despite complications necessitating medical and surgical interventions, vitrectomized eyes were effectively managed with AGV implantation.

  20. Ahmed Glaucoma Valve Implantation in Vitrectomized Eyes.

    Science.gov (United States)

    Erçalık, Nimet Yeşim; İmamoğlu, Serhat

    2018-01-01

    To evaluate the outcomes of Ahmed glaucoma valve (AGV) implantation in vitrectomized eyes. The medical records of 13 eyes that developed glaucoma due to emulsified silicon oil or neovascularization following pars plana vitrectomy and underwent AGV implantation were retrospectively reviewed. The main outcome measures were intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of antiglaucoma medications, and postoperative complications. Surgical success was defined as last IOP ≤21 mmHg or ≥6 mmHg and without loss of light perception. The mean follow-up duration was 11.7 ± 5.5 (range, 6-23) months. The mean IOP before the AGV implantation was 37.9 ± 6.7 mmHg with an average of 3.5 ± 1.2 drugs. At the final visit, the mean IOP was 15.9 ± 4.6 mmHg ( p =0.001) and the mean number of glaucoma medications decreased to 2.3 ± 1.3 ( p =0.021). At the last visit, 11 eyes (84.4%) had stable or improved VA and one eye (7.7%) had a final VA of no light perception. Surgical success was achieved in 11 of the 13 eyes (84.4%). Postoperative complications were bleb encapsulation (69.2%), early hypotony (38.5%), hyphema (23.1%), decompression retinopathy (23.1%), choroidal detachment (15.4%), intraocular hemorrhage (7.7%), and late endophthalmitis (7.7%). One eye (7.7%) was enucleated because of late endophthalmitis. Despite complications necessitating medical and surgical interventions, vitrectomized eyes were effectively managed with AGV implantation.

  1. The Ahmed versus Baerveldt study: three-year treatment outcomes.

    Science.gov (United States)

    Christakis, Panos G; Tsai, James C; Kalenak, Jeffrey W; Zurakowski, David; Cantor, Louis B; Kammer, Jeffrey A; Ahmed, Iqbal I K

    2013-11-01

    To compare 2 commonly used aqueous drainage devices for the treatment of refractory glaucoma. International, multicenter, randomized trial. Patients aged 18 years or older with uncontrolled or high-risk glaucoma refractory to maximum medical therapy, many of whom had failed trabeculoplasty and trabeculectomy. Eligible patients were randomized to an Ahmed-FP7 valve implant (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA) using a standardized surgical technique. The primary outcome was failure, defined as intraocular pressure (IOP) outside of the target range (5-18 mmHg, with ≥20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, de novo glaucoma procedures, or loss of light perception. Secondary outcome measures include IOP, medication use, visual acuity, complications, and interventions. A total of 238 patients were enrolled and randomized; 124 received the Ahmed implant and 114 received the Baerveldt implant. Baseline characteristics were similar in both groups. Half the study group had secondary glaucoma, and 37% had previously failed trabeculectomy. The mean preoperative IOP was 31.4±10.8 mmHg on 3.1±1.0 glaucoma medications. Median baseline Snellen visual acuity was 20/100. At 3 years, the cumulative probability of failure was 51% in the Ahmed group and 34% in the Baerveldt group (P = 0.03). Mean IOP was 15.7±4.8 mmHg in the Ahmed group (49% reduction) and 14.4±5.1 mmHg in the Baerveldt group (55% reduction; P = 0.09). Mean number of glaucoma medications was 1.8±1.4 in the Ahmed group (42% reduction) and 1.1±1.3 in the Baerveldt group (65% reduction; P = 0.002). There was a moderate but similar decrease in visual acuity in both groups (PAhmed, 62% Baerveldt; P = 0.12); however, the Baerveldt group had a higher rate of hypotony-related vision-threatening complications (0% Ahmed, 6% Baerveldt; P = 0.005). More interventions were

  2. Complications and 2-year valve survival following Ahmed valve implantation during the first 2 years of life.

    Science.gov (United States)

    Almobarak, F; Al-Mobarak, F; Khan, A O

    2009-06-01

    To report complications and 2-year valve survival following Ahmed valve implantation during the first 2 years of life. Retrospective institutional case series. Forty-two eyes of 36 patients with Ahmed valve implantation (without prior drainage device surgery) during the first 2 years of life and 2 years' postsurgical follow-up were identified. Most eyes had primary congenital glaucoma (28/42, 66.7%), aphakic glaucoma (5/42, 11.9%) or Peters anomaly (5/42, 11.9%). All but three eyes had prior ocular surgery. Surgery was at a mean age of 11.83 months (m) (SD 5.63). The most common significant postoperative complications were tube malpositioning requiring intervention (11/42, 26.2%), endophthalmitis (3/42, 7.1%; one with tube exposure) and retinal detachment (3/42, 7.1%). Thirty-six eyes (85.8%) required resumption of antiglaucoma medications to maintain intraocular pressure (IOP) valve survival (IOPendophthalmitis and retinal detachment are known potential complications following any incisional surgery for advanced buphthalmos; however, tube exposure is a unique potential problem following aqueous shunt implantation that can lead to intraocular infection. Cumulative valve survival 2 years following implantation was 63.3%.

  3. Partial Tenon’s capsule resection with adjunctive mitomycin C in Ahmed glaucoma valve implant surgery

    Science.gov (United States)

    Susanna, R

    2003-01-01

    Aim: To verify if partial intraoperative Tenon’s capsule resection (PTCR) with adjunctive mitomycin C is effective in developing thin, avascular blebs in eyes undergoing Ahmed glaucoma valve insertion, and to assess the efficacy and safety of this procedure. Methods: A multicentre, prospective, alternating case assignment, investigator unmasked, parallel group, comparative interventional study was conducted in four Latin American countries (Argentina, Brazil, Colombia, and Peru). Ahmed glaucoma valve implant insertion with PTCR (group A) and without PCTR (group B) was performed in neovascular glaucomatous eyes without previous surgery. Adjunctive mitomycin C (MMC) was used in both groups. Patients were examined 1 day, 10 days, 1 month, 2 months, 3 months, 6 months, and 1 year following the surgery. Intraocular pressure (IOP) and the appearance of the bleb were evaluated at each examination. Appearance of the bleb was classified at both the 1 month mark and last examinations into one of three groups: flat and vascularised; elevated avascular; or elevated and not avascular. Results: 92 eyes from 92 patients were included in the study. The preoperative mean IOP was 50.0 (SD 10.5) mm Hg in group A and 48.4 (11.7) in group B (p>0.05). Statistically significant IOP reductions were observed at all periods of follow up. 12 months after surgery, the mean IOP was 17.2 (5.0) mm Hg in group A and 18.3 (8.7) mm Hg in group B (p>0.05). A hypertensive phase occurred in 40.0% in group A and in 46.8% in group B (p>0.05). At the 1 month and the final follow up, the blebs in all eyes were considered elevated and not avascular. The success rate (IOP⩽21 mm Hg) at 1 year after surgery was 70.4% in group A and 77.7% in group B (p>0.05). Overall, 74.2% of the patients achieved an IOP ⩽21 mm Hg and 55.2% an IOP⩽17 mm Hg, with or without additional medication administered to lower IOP. The incidence of complications was similar in both groups. Conclusions: In eyes undergoing Ahmed

  4. Intercostal drainage tube or intracardiac drainage tube?

    Directory of Open Access Journals (Sweden)

    N Anitha

    2016-01-01

    Full Text Available Although insertion of chest drain tubes is a common medical practice, there are risks associated with this procedure, especially when inexperienced physicians perform it. Wrong insertion of the tube has been known to cause morbidity and occasional mortality. We report a case where the left ventricle was accidentally punctured leading to near-exsanguination. This report is to highlight the need for experienced physicians to supervise the procedure and train the younger physician in the safe performance of the procedure.

  5. Intercostal drainage tube or intracardiac drainage tube?

    Science.gov (United States)

    Anitha, N; Kamath, S Ganesh; Khymdeit, Edison; Prabhu, Manjunath

    2016-01-01

    Although insertion of chest drain tubes is a common medical practice, there are risks associated with this procedure, especially when inexperienced physicians perform it. Wrong insertion of the tube has been known to cause morbidity and occasional mortality. We report a case where the left ventricle was accidentally punctured leading to near-exsanguination. This report is to highlight the need for experienced physicians to supervise the procedure and train the younger physician in the safe performance of the procedure.

  6. Experimental insertions

    International Nuclear Information System (INIS)

    Sandweiss, J.; Kycia, T.F.

    1975-01-01

    A discussion is given of the eight identical experimental insertions for the planned ISABELLE storage rings. Four sets of quadrupole doublets are used to match the β functions in the insertions to the values in the cells, and the total free space available at the crossing point is 40 meters. An asymmetric beam energy operation is planned, which will be useful in a number of experiments

  7. Superior versus inferior Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Pakravan, Mohammad; Yazdani, Shahin; Shahabi, Camelia; Yaseri, Mehdi

    2009-02-01

    To compare the efficacy and safety of Ahmed glaucoma valve (AGV) (New World Medical Inc., Rancho Cucamonga, CA) implantation in the superior versus inferior quadrants. Prospective parallel cohort study. A total of 106 eyes of 106 patients with refractory glaucoma. Consecutive patients with refractory glaucoma underwent AGV implantation in the superior or inferior quadrants. Main outcome measures included intraocular pressure (IOP) and rate of complications. Other outcome measures included best corrected visual acuity (BCVA), number of glaucoma medications, and success rate (defined as at least 30% IOP reduction and 5glaucoma surgery, phthisis bulbi, or loss of light perception. Of a total of 106 eyes, 58 and 48 eyes underwent AGV implantation in the superior and inferior quadrants, respectively. Baseline characteristics were comparable in the study groups, except for preoperative IOP, which was higher in the superior group (P = 0.01). Patients were followed for a mean period of 10.6+/-8.49 months and 10.58+/-6.75 months in the superior and inferior groups, respectively (P = 0.477). BCVA was comparable between the groups at all postoperative visits (P>0.122). After 1 year, statistically significant but comparable IOP reduction from baseline (Pglaucoma medications was comparable after 1 year (1.3+/-1.2 vs. 1.9+/-0.8 for superior and inferior implants, respectively, P = 0.256). Success rates were also similar at 1 year: 27 eyes (81.8%) versus 20 eyes (95.2%) for superior and inferior implants, respectively (P = 0.227). However, the overall rate of complications, such as implant exposure necessitating removal, cosmetically unappealing appearance, and endophthalmitis, was higher in the inferior group: 12 eyes (25%) versus 3 eyes (5.2%) for superior and inferior groups, respectively, (P = 0.004). Superior and inferior AGV implants have similar intermediate efficacy in terms of IOP reduction, decrease in number of glaucoma medications, and preservation of vision. However

  8. Technique for joining metal tubing

    Science.gov (United States)

    Wright, H. W.

    1976-01-01

    Uniform wall thickness and uninterrupted heat transfer is achieved by using shaped metal insert as wall material for joint. Insert acts as support during brazing, after which excess material is ground away to bring joint to original tubing size.

  9. Definition of the minimum longitude of insert in the rebuilding of Charpy test tubes for surveillance and life extension of vessels in Mexico; Definicion de la longitud minima de inserto en la reconstitucion de probetas Charpy para vigilancia y extension de vida de vasijas en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Romero C, J.; Hernandez C, R.; Rocamontes A, M., E-mail: jesus.romero@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    In the National Institute of Nuclear Research (Mexico) a welding system for the rebuilding of Charpy test tubes has been developed, automated, qualified and used for the surveillance of the mechanical properties (mainly embrittlement) of the vessel. This system uses the halves of the rehearsed Charpy test tubes of the surveillance capsules extracted of the reactors, to obtain, of a rehearsed test tube, two reconstituted test tubes. This rebuilding process is used so much in the surveillance program like in the potential extension of the operation license of the vessel. To the halves of Charpy test tubes that have been removed the deformed part by machine are called -insert- and in a very general way the rebuilding consists in weld with the welding process -Stud Welding- two metallic implants in the ends of the insert, to obtain a reconstituted test tube. The main characteristic of this welding are the achieved small dimensions, so much of the areas welded as of the areas affected by the heat. The applicable normative settles down that the minim longitude of the insert for the welding process by Stud Welding it should be of 18 mm, however according to the same normative this longitude can diminish if is demonstrated analytic or experimentally that the central volume of 1 cm{sup 3} in the insert is not affected. In this work the measurement of the temperature profiles to different distances of the welding interface is presented, defining an equation for the maximum temperatures reached in function of the distance, on the other hand the real longitude affected in the test tube by means of metallography is determined and this way the minimum longitude of the insert for this developed rebuilding system was determined. (Author)

  10. Application of 5-Fluorouracil-Polycaprolactone Sustained-Release Film in Ahmed Glaucoma Valve Implantation Inhibits Postoperative Bleb Scarring in Rabbit Eyes.

    Science.gov (United States)

    Bi, Xiu-Zeng; Pan, Wei-Hua; Yu, Xin-Ping; Song, Zong-Ming; Ren, Zeng-Jin; Sun, Min; Li, Cong-Hui; Nan, Kai-Hui

    2015-01-01

    This study was designed to investigate whether 5-fluorouracil (5-Fu)-polycaprolactone sustained-release film in Ahmed glaucoma valve implantation inhibits postoperative bleb scarring in rabbit eyes. Eighteen New Zealand white rabbits were randomly divided into three groups (A, B and C; n = 6 per group). Group A received combined 5-Fu-polycaprolactone sustained-release film application and Ahmed glaucoma valve implantation, group B received local infiltration of 5-Fu and Ahmed glaucoma valve implantation, and group C received Ahmed glaucoma valve implantation. Postoperative observations were made of the anterior segment, intraocular pressure, central anterior chamber depth, blebs, drainage tube, and accompanying ciliary body detachment. The pathology of the blebs and surrounding tissues were observed at month 3 postoperatively. We revealed that the 5-Fu-polycaprolactone sustained-release film maintained a release concentration range of 13.7 ± 0.12 to 37.41 ± 0.47 μg/ml over three months in vitro. Postoperatively, diffuse blebs with ridges were found in all eyes in group A, two blebs were observed in group B, and no bleb formation was present in group C. The postoperative central anterior chamber depth in group A was significantly less than that of the other two groups. The postoperative intraocular pressure of group A stabilized at 6.33-8.67 mmHg, whereas that of group C gradually remained at 7.55-10.02 mmHg. The histopathology showed that the fibrous tissue thickness of the blebs in group A was significantly thinner than that of the other groups. We conclude that the 5-Fu-polycaprolactone sustained-release film had a sustained drug release effect, which promoted the inhibition of bleb scarring after Ahmed glaucoma valve implantation.

  11. 77 FR 42546 - In the Matter of the Designation of Ahmed Abdulrahman Sihab Ahmed Sihab as a Specially Designated...

    Science.gov (United States)

    2012-07-19

    ... DEPARTMENT OF STATE [Public Notice 7957] In the Matter of the Designation of Ahmed Abdulrahman... Sihab, committed, or poses a significant risk of committing, acts of terrorism that threaten the security of U.S. nationals or the national security, foreign policy, or economy of the United States...

  12. Clinical observation of Ahmed glaucoma valve implantation for refractory glaucoma by directly puncturing the sclerotic tunnel

    Directory of Open Access Journals (Sweden)

    Zhi-Ke Xu

    2015-02-01

    Full Text Available AIM: To observe the clinic effects and complication of Ahmed glaucoma valve(AGVimplantation in refractory glaucoma by using the 23G syringe needle direct puncture the sclerotic tunnel.METHODS: Forty-four cases(44 eyesof refractory glaucoma underwent AGV implantation by useing the 23G syringe needle direct puncture the sclerotic tunnel. The intraocular pressure(IOP, visual acuity, and complication of post-operation were contrasted with those of pre-operation. RESULTS:The success rate was 84.1%, the mean preoperative IOP in research group was 52.1±10.1mmHg, and the last follow up mean IOP was 15.6±6.9mmHg. Compared with the preoperative visual acuity, 11 eyes increased, 27 eyes had no changes and 6 eyes decreased. The main post-operative complications included shallow anterior chamber(4 eyes, choroidal detachment(3 eyes, drainage tube shift(1 eye, hyphema(6 eyes, drainage tube blockage(1 eye, expulsive choroidal hemorrhage(1 eye, and fiber wrap of drainage tray(5 eyes.CONCLUSION: AGV implantation by direct puncture the sclerotic tunnel is feasible and easy. It avoids of making sclerotic petal and the xenogenic sclera transplanting, simplified the operation technique, prevent the leakage of around tube. The shallow anterior chamber rate is lower. It is an effective procedure for refractory glaucoma.

  13. Vacuum guidelines for ISA insertions

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1976-01-01

    Vacuum requirements place design restrictions on the ISA insertions. The vacuum tube diameter, given a distance L between pumps, is determined by the desorption of molecules from the wall under the impact of ions created by the beam, whereas the thickness of the tube must be sufficient to prevent collapse. In addition, the entire vacuum chamber must be able to be baked out at approximately 200 0 C

  14. Heat exchanger tube tool

    International Nuclear Information System (INIS)

    Gugel, G.

    1976-01-01

    Certain types of heat-exchangers have tubes opening through a tube sheet to a manifold having an access opening offset from alignment with the tube ends. A tool for inserting a device, such as for inspection or repair, is provided for use in such instances. The tool is formed by a flexible guide tube insertable through the access opening and having an inner end provided with a connector for connection with the opening of the tube in which the device is to be inserted, and an outer end which remains outside of the chamber, the guide tube having adequate length for this arrangement. A flexible transport hose for internally transporting the device slides inside of the guide tube. This hose is long enough to slide through the guide tube, into the heat-exchanger tube, and through the latter to the extent required for the use of the device. The guide tube must be bent to reach the end of the heat-exchanger tube and the latter may be constructed with a bend, the hose carrying anit-friction elements at interspaced locations along its length to make it possible for the hose to negotiate such bends while sliding to the location where the use of the device is required

  15. Dr Ahmed Zaky Abushady: author, beekeeper, doctor and poet.

    Science.gov (United States)

    Wright, David

    2013-12-01

    Ahmed Zaky Abushady, (1892-1955) was an author, beekeeper, doctor and poet. This paper follows his life from his upbringing in Egypt and his time as a medical student in England to his later life as a pathologist working in Alexandria and Cairo and finally his years in the United States of America. It emphasises his contributions in several fields not directly related to medicine and looks at his continuing influence.

  16. Trabeculectomy versus Ahmed Glaucoma Valve implantation in neovascular glaucoma

    OpenAIRE

    Netland, Peter; Shen,Chris; Salim,Sarwat; Du,Haiming

    2011-01-01

    Christopher C Shen1, Sarwat Salim2, Haiming Du2, Peter A Netland31Glaucoma Consultants Northwest, Seattle, WA, USA; 2University of Tennessee Health Science Center, Memphis, TN, USA; 3University of Virginia School of Medicine, Charlottesville, VA, USAPurpose: To compare surgical outcomes in neovascular glaucoma patients who underwent trabeculectomy with mitomycin C versus Ahmed Glaucoma Valve implantation. Patients and methods: This was a retrospective comparative case series. We reviewed 40 e...

  17. From structure to structural dynamics: Ahmed Zewail's legacy

    Directory of Open Access Journals (Sweden)

    Majed Chergui

    2017-07-01

    Full Text Available In this brief tribute to Ahmed Zewail, we highlight and place in the historical context, several of the major achievements that he and his colleagues have made in Femtochemistry (of which he was the principal instigator and his introduction of ultrafast electron scattering, diffraction, microscopy and spectroscopy. By achieving a sub-picosecond temporal resolution, coupled with a picometer spatial resolution, he revolutionised our understanding of the corpus of chemical, physical, biological and materials science systems.

  18. Outcomes of using a sutureless bovine pericardial patch graft for Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Quaranta, Luciano; Riva, Ivano; Floriani, Irene C

    2013-01-01

    To evaluate the long-term outcomes of a surgical technique using a sutureless bovine pericardial patch graft for the implantation of an Ahmed glaucoma valve (AGV). 
 This was a pilot study on patients with primary open-angle glaucoma refractory to repeated surgical filtering procedures. All patients underwent AGV implant technique using a sutureless bovine pericardial patch graft. The pericardial membrane was cut using an ordinary corneal trephine with a diameter of 9.0 or 10.0 mm. The anterior part of the tube was covered with the graft and kept in place with fibrin glue. Subsequently, the cap was stitched all around the tube and the dissected conjunctiva was laid over it. Intraocular pressure (IOP) and complications were evaluated 1 week and 1, 3, 6, 12, and 24 months after surgery.
 The procedure was used to treat 20 eyes of 20 consecutive patients (12 men and 8 women: mean age [SD] 64.8 [7.8] years). Mean IOP was 28.1 mm Hg (SD 4.9) at baseline and decreased to 14.9 mm Hg (SD 1.5) 24 months after surgery (pendophthalmitis were recorded.
 The results suggest that the sutureless technique using a bovine pericardial graft patch is a safe and rapid procedure for AGV implantation.

  19. Clinical Experience with the M4 Ahmed Glaucoma Drainage Implant.

    Science.gov (United States)

    Sluch, Ilya; Gudgel, Brett; Dvorak, Justin; Anne Ahluwalia, Mary; Ding, Kai; Vold, Steve; Sarkisian, Steven

    2017-01-01

    To evaluate the safety and efficacy of the M4 (porous polyethylene plate) Ahmed Glaucoma Valve (AGV) drainage implant in a multicenter retrospective study. A retrospective chart review of medical records of patients who had undergone the M4 Ahmed valve was performed from January 2013 to April 2015. The primary outcome measure was surgical failure defined as: Less than a 20% reduction in baseline intraocular pressure (IOP) to last follow-up visit, final IOP less than 5 mm Hg or greater than 18 mm Hg, reoperation for glaucoma, or loss of light perception vision. All eyes not meeting the above criteria were defined as success. A total of 291 eyes met all study inclusion criteria. The average follow-up in the study was 6 months (±7.6 months) with 112 patients achieving 12-month follow-up (38.5%). 208 eyes (71.5%) met the study success criteria at final follow-up. No statistically significant spikes in postoperative IOP at 1 and 4 months were detected. The average preoperative IOP was 26.0 on an average of 2.8 medications. At 6 months, the average IOP dropped to 16.7 on 0.9 medications and stayed relatively stable at 15.8 on 1.2 medications at 12-month follow-up. The M4 valve appears to have less of a hypertensive phase compared with the other Ahmed class valves with a similar safety profile. While 71.5% success rate was achieved at final follow-up, the failure rate steadily increased over time. While the M4 production has been discontinued, the porous design of the M4 may avoid a pressure spike in the Ahmed valve class and warrants future investigation for valve design. How to cite this article: Sluch I, Gudgel B, Dvorak J, Ahluwalia MA, Ding K, Vold S, Sarkisian S. Clinical Experience with the M4 Ahmed Glaucoma Drainage Implant. J Curr Glaucoma Pract 2017;11(3):92-96.

  20. Evaluación de la válvula de Ahmed en el glaucoma de mal pronóstico quirúrgico Evaluation of Ahmed valve in the glaucoma of poor surgical prognosis

    Directory of Open Access Journals (Sweden)

    Francisco García González

    2001-12-01

    Full Text Available Se intervinieron 8 pacientes con glaucoma de mal pronóstico quirúrgico a los que se les implantaron una válvula de Ahmed con la técnica quirúrgica convencional. Se logró controlar la presión intraocular (PIO. Las complicaciones fueron: hipotonía (75 %, desprendimiento coroideo (37,5 %, hifema (25,0 %, contacto tubo iridiano (25, 0 %, hipotalamia (12,5 % y congestión en el área del implante (12,5 %. No hubo complicaciones intraoperatorias. Se obtuvieron resultados satisfactorios a mediano plazo.8 patients with glaucoma of poor surgical prognosis were implanted an Ahmed valve by using the conventional surgical technique. It was possible to control the intraocular pressure (IOP. The complications were: hypotony (75 %, choroidal detachment (37.5 %, hyphaemia (25.0 %, contact with the iridian tube (25.0 %, hypothalamia (12.5 % and congestion in the area of the implantation (12.5 %. There were no intraoperative complications. Medium term results were satisfactory.

  1. Partial Tenon's capsule resection with adjunctive mitomycin C in Ahmed glaucoma valve implant surgery.

    Science.gov (United States)

    Susanna, R

    2003-08-01

    To verify if partial intraoperative Tenon's capsule resection (PTCR) with adjunctive mitomycin C is effective in developing thin, avascular blebs in eyes undergoing Ahmed glaucoma valve insertion, and to assess the efficacy and safety of this procedure. A multicentre, prospective, alternating case assignment, investigator unmasked, parallel group, comparative interventional study was conducted in four Latin American countries (Argentina, Brazil, Colombia, and Peru). Ahmed glaucoma valve implant insertion with PTCR (group A) and without PCTR (group B) was performed in neovascular glaucomatous eyes without previous surgery. Adjunctive mitomycin C (MMC) was used in both groups. Patients were examined 1 day, 10 days, 1 month, 2 months, 3 months, 6 months, and 1 year following the surgery. Intraocular pressure (IOP) and the appearance of the bleb were evaluated at each examination. Appearance of the bleb was classified at both the 1 month mark and last examinations into one of three groups: flat and vascularised; elevated avascular; or elevated and not avascular. 92 eyes from 92 patients were included in the study. The preoperative mean IOP was 50.0 (SD 10.5) mm Hg in group A and 48.4 (11.7) in group B (p>0.05). Statistically significant IOP reductions were observed at all periods of follow up. 12 months after surgery, the mean IOP was 17.2 (5.0) mm Hg in group A and 18.3 (8.7) mm Hg in group B (p>0.05). A hypertensive phase occurred in 40.0% in group A and in 46.8% in group B (p>0.05). At the 1 month and the final follow up, the blebs in all eyes were considered elevated and not avascular. The success rate (IOP0.05). Overall, 74.2% of the patients achieved an IOP glaucoma, PCTR with MMC augmentation showed no additional benefits or complications over MMC augmentation alone; no avascular bleb was obtained with this technique. The incidence of a hypertensive phase was lower than reported in previous studies.

  2. Simultaneous Implantation of an Ahmed and Baerveldt Glaucoma Drainage Device for Uncontrolled Intraocular Pressure in Advanced Glaucoma.

    Science.gov (United States)

    Rao, Veena S; Christenbury, Joseph; Lee, Paul; Allingham, Rand; Herndon, Leon; Challa, Pratap

    2017-02-01

    To evaluate efficacy and safety of a novel technique, simultaneous implantation of Ahmed and Baerveldt shunts, for improved control of intraocular pressure (IOP) in advanced glaucoma with visual field defects threatening central fixation. Retrospective case series; all patients receiving simultaneous Ahmed and Baerveldt implantation at a single institution between October 2004 and October 2009 were included. Records were reviewed preoperatively and at postoperative day 1, week 1, month 1, month 3, month 6, year 1, and yearly until year 5. Outcome measures included IOP, best-corrected visual acuity, visual field mean deviation, cup to disc ratio, number of glaucoma medications, and complications. Fifty-nine eyes were identified; mean (±SD) follow-up was 26±23 months. Primary open-angle glaucoma was most common (n=37, 63%). Forty-six eyes (78%) had prior incisional surgery. Mean preoperative IOP was 25.5±9.8 mm Hg. IOP was reduced 50% day 1 (Pglaucoma tube implantation with effects persisting over postoperative year 1 and up to year 5. Complications were higher than that seen in reports of single shunt implantation, which may be explained by patient complexity in this cohort. This technique may prove a promising novel approach for management of uncontrolled IOP in advanced glaucoma.

  3. Hypertensive phase and early complications after Ahmed glaucoma valve implantation with intraoperative subtenon triamcinolone acetonide

    Directory of Open Access Journals (Sweden)

    Turalba AV

    2014-07-01

    Full Text Available Angela V Turalba,1,2 Louis R Pasquale1,2 1Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA; 2Department of Ophthalmology, Harvard Medical School, Boston, MA, USA Objective: To evaluate intraoperative subtenon triamcinolone acetonide (TA as an adjunct to Ahmed glaucoma valve (AGV implantation. Design: Retrospective comparative case series. Participants: Forty-two consecutive cases of uncontrolled glaucoma undergoing AGV implantation: 19 eyes receiving intraoperative subtenon TA and 23 eyes that did not receive TA.Methods: A retrospective chart review was performed on consecutive pseudophakic adult patients with uncontrolled glaucoma undergoing AGV with and without intraoperative subtenon TA injection by a single surgeon. Clinical data were collected from 42 eyes and analyzed for the first 6 months after surgery.Main outcome measures: Primary outcomes included intraocular pressure (IOP and number of glaucoma medications prior to and after AGV implantation. The hypertensive phase (HP was defined as an IOP measurement of greater than 21 mmHg (with or without medications during the 6-month postoperative period that was not a result of tube obstruction, retraction, or malfunction. Postoperative complications and visual acuity were analyzed as secondary outcome measures. Results: Five out of 19 (26% TA cases and 12 out of 23 (52% non-TA cases developed the HP (P=0.027. Mean IOP (14.2±4.6 in TA cases versus [vs] 14.7±5.0 mmHg in non-TA cases; P=0.78, and number of glaucoma medications needed (1.8±1.3 in TA cases vs 1.6±1.1 in the comparison group; P=0.65 were similar between both groups at 6 months. Although rates of serious complications did not differ between the groups (13% in the TA group vs 16% in the non-TA group, early tube erosion (n=1 and bacterial endophthalmitis (n=1 were noted with TA but not in the non-TA group.Conclusions: Subtenon TA injection during AGV implantation may decrease the

  4. Bradycardia after Tube Thoracostomy for Spontaneous Pneumothorax

    Directory of Open Access Journals (Sweden)

    Yomi Fashola

    2018-01-01

    Full Text Available We present the case of an elderly patient who became bradycardic after chest tube insertion for spontaneous pneumothorax. Arrhythmia is a rare complication of tube thoracostomy. Unlike other reported cases of chest tube induced arrhythmias, the bradycardia in our patient responded to resuscitative measures without removal or repositioning of the tube. Our patient, who had COPD, presented with shortness of breath due to spontaneous pneumothorax. Moments after tube insertion, patient developed severe bradycardia that responded to Atropine. In patients requiring chest tube insertion, it is important to be prepared to provide cardiopulmonary resuscitative therapy in case the patient develops a life-threatening arrhythmia.

  5. Leakproof Swaged Joints in Thin-Wall Tubing

    Science.gov (United States)

    Stuckenberg, F. H.; Crockett, L. K.; Snyder, W. E.

    1986-01-01

    Tubular inserts reinforce joints, reducing incidence of leaks. In new swaging technique, tubular inserts placed inside ends of both tubes to be joined. Made from thicker-wall tubing with outside diameter that matches inside diameter of thin tubing swaged, inserts support tube ends at joint. They ensure more uniform contact between swage fitting and tubing. New swaging technique developed for Al/Ti/V-alloy hydraulic supply lines.

  6. Spring/dimple instrument tube restraint

    International Nuclear Information System (INIS)

    DeMario, E.E.; Lawson, C.N.

    1993-01-01

    A nuclear fuel assembly for a pressurized water nuclear reactor has a spring and dimple structure formed in a non-radioactive insert tube placed in the top of a sensor receiving instrumentation tube thimble disposed in the fuel assembly and attached at a top nozzle, a bottom nozzle, and intermediate grids. The instrumentation tube thimble is open at the top, where the sensor or its connection extends through the cooling water for coupling to a sensor signal processor. The spring and dimple insert tube is mounted within the instrumentation tube thimble and extends downwardly adjacent the top. The springs and dimples restrain the sensor and its connections against lateral displacement causing impact with the instrumentation tube thimble due to the strong axial flow of cooling water. The instrumentation tube has a stainless steel outer sleeve and a zirconium alloy inner sleeve below the insert tube adjacent the top. The insert tube is relatively non-radioactivated inconel alloy. The opposed springs and dimples are formed on diametrically opposite inner walls of the insert tube, the springs being formed as spaced axial cuts in the insert tube, with a web of the insert tube between the cuts bowed radially inwardly for forming the spring, and the dimples being formed as radially inward protrusions opposed to the springs. 7 figures

  7. Managing a chest tube and drainage system.

    Science.gov (United States)

    Durai, Rajaraman; Hoque, Happy; Davies, Tony W

    2010-02-01

    Intercostal drainage tubes (ie, chest tubes) are inserted to drain the pleural cavity of air, blood, pus, or lymph. The water-seal container connected to the chest tube allows one-way movement of air and liquid from the pleural cavity. The container should not be changed unless it is full, and the chest tube should not be clamped unnecessarily. After a chest tube is inserted, a nurse trained in chest-tube management is responsible for managing the chest tube and drainage system. This entails monitoring the chest-tube position, controlling fluid evacuation, identifying when to change or empty the containers, and caring for the tube and drainage system during patient transport. This article provides an overview of indications, insertion techniques, and management of chest tubes. Copyright 2010 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  8. Initial Clinical Experience with Ahmed Valve Implantation in Refractory Pediatric Glaucoma

    Science.gov (United States)

    Novak-Lauš, Katia; Škunca Herman, Jelena; Šimić Prskalo, Marija; Jurišić, Darija; Mandić, Zdravko

    2016-12-01

    The purpose is to report on the safety and efficacy of Ahmed Glaucoma Valve (AGV, New World Medical, Inc., Rancho Cucamonga, CA, USA) implantation for the management of refractory pediatric glaucoma observed during one-year follow up period. A retrospective chart review was conducted on 10 eyes, all younger than 11 years, with pediatric glaucoma that underwent AGV implantation for medicamentously uncontrolled intraocular pressure (IOP) between 2010 and 2014. Outcome measures were control of IOP below 23 mm Hg (with or without antiglaucoma medications) and changes in visual acuity. Complications were recorded. After AGV implantation, IOP values ranged from 18 mm Hg to 23 mm Hg (except for one eye with postoperative hypotonia due to suprachoroid hemorrhage, where the postoperative IOP value was 4 mm Hg). The number of antiglaucoma medications was reduced, i.e. four patients had two medications, one patient had one medication, and the others did not need antiglaucoma medication on the last follow-up visit. One eye had suprachoroid hemorrhage, one eye had long-term persistent uveitic membrane, and two eyes had tube-cornea touch. In conclusion, AGV implantation appears to be a viable option for the management of refractory pediatric glaucoma and shows success in IOP control. However, there was a relatively high complication rate limiting the overall success rate.

  9. Dual infection by streptococcus and atypical mycobacteria following Ahmed glaucoma valve surgery.

    Science.gov (United States)

    Rao, Aparna; Wallang, Batriti; Padhy, Tapas Ranjan; Mittal, Ruchi; Sharma, Savitri

    2013-07-01

    To report a case of late postoperative endophthalmitis caused by Streptococcus pneumoniae and conjunctival necrosis by Streptococcus pneumoniae and Mycobacterium fortuitum following Ahmed glaucoma valve (AGV) surgery in a young patient. Case report of a 13-year-old boy with purulent exudates and extensive conjunctival necrosis two months following amniotic membrane graft and conjunctival closure (for conjunctival retraction post AGV for secondary glaucoma). The conjunctiva showed extensive necrosis causing exposure of the tube and plate associated with frank exudates in the area adjoining the plate and anterior chamber mandating explantation of the plate along with intravitreal antibiotics. The vitreous aspirate grew Streptococcus pneumoniae while Streptococcus pneumoniae with Mycobacterium fortuitum was isolated from the explanted plate. Despite adequate control of infection following surgery, the final visual outcome was poor owing to disc pallor. Conjunctival necrosis and retraction post-AGV can cause late postoperative co-infections by fulminant and slow-growing organisms. A close follow-up is therefore essential in these cases to prevent sight-threatening complications.

  10. Comparison of polypropylene and silicone Ahmed Glaucoma Valves.

    Science.gov (United States)

    Ishida, Kyoko; Netland, Peter A; Costa, Vital P; Shiroma, Lineu; Khan, Baseer; Ahmed, Iqbal Ike K

    2006-08-01

    To evaluate and compare the clinical outcomes after implantation of the silicone plate and the polypropylene plate Ahmed Glaucoma Valves. Prospective, multicenter, comparative series. A total of 132 patients with uncontrolled glaucoma were treated with either the silicone or polypropylene Ahmed Glaucoma Valve implant. Success was defined according to 2 criteria: (1) intraocular pressure (IOP) of 6 mmHg or more or 21 mmHg or less, and (2) IOP reduction of at least 30% relative to preoperative values. Eyes requiring further glaucoma surgery, including cyclophotocoagulation, or showing loss of light perception were classified as failures. Average follow-up was 12.8 months (range, 6-30 months) for the silicone plate group and 14.5 months (range, 6-30 months) for the polypropylene plate group (P = 0.063). At the last follow-up examination, the mean IOP was 13.8+/-3.9 mmHg and 17.3+/-6.5 mmHg (PAhmed Glaucoma Valve (model FP7) showed improved IOP reduction compared with the polypropylene (model S2) implant. Differences observed in mean IOP, success rate, and complications suggest that plate material may influence clinical outcome.

  11. Reliable experimental setup to test the pressure modulation of Baerveldt Implant tubes for reducing post-operative hypotony

    Science.gov (United States)

    Ramani, Ajay

    Glaucoma encompasses a group of conditions that result in damage to the optic nerve and can cause loss of vision and blindness. The nerve is damaged due to an increase in the eye's internal (intraocular) pressure (IOP) above the nominal range of 15 -- 20 mm Hg. There are many treatments available for this group of diseases depending on the complexity and stage of nerve degradation. In extreme cases where drugs or laser surgery do not create better conditions for the patient, ophthalmologists use glaucoma drainage devices to help alleviate the IOP. Many drainage implants have been developed over the years and are in use; but two popular implants are the Baerveldt Glaucoma Implant and the Ahmed Glaucoma Valve Implant. Baerveldt Implants are non-valved and provide low initial resistance to outflow of fluid, resulting in post-operative complications such as hypotony, where the IOP drops below 5 mm of Hg. Ahmed Glaucoma Valve Implants are valved implants which initially restrict the amount of fluid flowing out of the eye. The long term success rates of Baerveldt Implants surpass those of Ahmed Valve Implants because of post-surgical issues; but Baerveldt Implants' initial effectiveness is poor without proper flow restriction. This drives the need to develop new ways to improve the initial effectiveness of Baerveldt Implants. A possible solution proposed by our research team is to place an insert in the Baerveldt Implant tube of inner diameter 305 microns. The insert must be designed to provide flow resistance for the early time frame [e.g., first 30 -- 60 post-operative days] until sufficient scar tissue has formed on the implant. After that initial stage with the insert, the scar tissue will provide the necessary flow resistance to maintain the IOP above 5 mm Hg. The main objective of this project was to develop and validate an experimental apparatus to measure pressure drop across a Baerveldt Implant tube, with and without inserts. This setup will be used in the

  12. Enhancement of heat transfer using varying width twisted tape inserts

    African Journals Online (AJOL)

    user

    enhancement of heat transfer with twisted tape inserts as compared to plain ... studies for heat transfer and pressure drop of laminar flow in horizontal tubes ... flow in rectangular and square plain ducts and ducts with twisted-tape inserts .... presence of the insert in the pipe causes resistance to flow and increases turbulence.

  13. Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure

    Directory of Open Access Journals (Sweden)

    Huang J

    2015-06-01

    Full Text Available Jingjing Huang,1 Jialiu Lin,1 Ziqiang Wu,2 Hongzhi Xu,3 Chengguo Zuo,1 Jian Ge1 1State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Center for Advanced Eye Care, Carson City, NV, USA; 3Institute of Child Health Policy, University of Florida, Gainesville, FL, USA Purpose: The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve (AGV implantation in patients less than 7 years of age, with advanced primary congenital glaucoma who have failed previous surgeries.Patients and methods: Consecutive patients with advanced primary congenital glaucoma that failed previous operations and had undergone subsequent AGV implantation were evaluated retrospectively. Surgical success was defined as 1 intraocular pressure (IOP ≥6 and ≤21 mmHg; 2 IOP reduction of at least 30% relative to preoperative values; and 3 without the need for additional surgical intervention for IOP control, loss of light perception, or serious complications.Results: Fourteen eyes of eleven patients were studied. Preoperatively, the average axial length was 27.71±1.52 (25.56–30.80 mm, corneal diameter was 14.71±1.07 (13.0–16.0 mm, cup-to-disc ratio was 0.95±0.04 (0.9–1.0, and IOP was 39.5±5.7 (30–55 mmHg. The mean follow-up time was 18.29±10.96 (5–44, median 18 months. There were significant reductions in IOPs and the number of glaucoma medications (P<0.001 postoperatively. The IOPs after operation were 11.3±3.4, 13.6±5.1, 16.3±2.7, and 16.1±2.6 mmHg at 1 month, 6 months, 12 months, and 18 months, respectively. Kaplan–Meier estimates of the cumulative probability of valve success were 85.7%, 71.4%, and 71.4% at 6, 12, and 18 months, respectively. Severe surgical complications, including erosion of tube, endophthalmitis, retinal detachment, choroidal detachment, and delayed suprachoroidal hemorrhage, occurred in 28

  14. Comparative study of encapsulated blebs following Ahmed glaucoma valve implantation and trabeculectomy with mitomycin-C.

    Science.gov (United States)

    Bae, Kunho; Suh, Wool; Kee, Changwon

    2012-08-01

    To compare the histopathologic and morphologic findings of encapsulated blebs following Ahmed glaucoma valve implantation and primary standard trabeculectomy with mitomycin-C. We reviewed the records of patients with otherwise uncontrollable glaucoma who had undergone Ahmed glaucoma valve implantation or trabeculectomy with mitomycin-C. Five eyes that underwent Ahmed valve implantation and three eyes that underwent trabeculectomy needed surgical revision of the initial surgery due to encapsulated bleb development with total loss of function. The surgically removed encapsulated blebs were analyzed macroscopically and microscopically. Removal of the encapsulated bleb was performed at a mean follow-up time of 26.6 ± 19.4 weeks in the Ahmed valve implantation group and 12.0 ± 11.4 weeks in the trabeculectomy group. The fibrotic wall of the encapsulated blebs had an overall thickness of 2.48 ± 0.42 mm in the Ahmed valve implantation group and 1.62 ± 0.37 mm in the trabeculectomy group. Macroscopically, the coconut flesh-like smooth surface was split into two layers, and the wall of the capsule was thicker in the Ahmed valve implantation group than in the trabeculectomy group. Histopathologically, the fibrotic capsule was composed of an inner fibrodegenerative layer and an outer fibrovascular layer, and there were no histopathological differences between the two groups. The fibrotic capsule wall was thicker in the Ahmed valve group, but there were no differences in histological findings between the two groups.

  15. Trabeculectomy With Mitomycin C or Ahmed Valve Implantation in Eyes With Uveitic Glaucoma.

    Science.gov (United States)

    Bettis, Daniel I; Morshedi, Richard G; Chaya, Craig; Goldsmith, Jason; Crandall, Alan; Zabriskie, Norm

    2015-01-01

    To report and compare the results of trabeculectomy with mitomycin C (MMC) and Ahmed valve implantation in the management of uveitic glaucoma. The records of 41 eyes of 29 patients who underwent trabeculectomy with MMC or Ahmed valve implantation for uveitic glaucoma were retrospectively reviewed. Seventeen eyes underwent trabeculectomy with MMC, and 24 eyes underwent Ahmed valve implantation. Outcomes included postoperative intraocular pressure (IOP), percent reduction from preoperative IOP, postoperative number of medications, time to failure, and complications. Mean follow-up was 21.2 months in the trabeculectomy group and 23.8 months in the valve group (P=0.06). Mean IOP was reduced from 29.2 to 18.4 mm Hg in the trabeculectomy group (31.3%), compared with a reduction from 33.4 to 15.5 mm Hg in the Ahmed valve group (42.7%, P=0.53). Postoperatively, 1.76 medications were used in the trabeculectomy group, compared with 1.83 medications in the Ahmed valve group (P=0.89). Cumulative success at 1 year was 66.7% in the trabeculectomy group, compared with 100% in the Ahmed valve group (P=0.02). Mean time to failure was 8.36 months with trabeculectomy, and 21.8 months with Ahmed valve (P=0.02). Complications in both groups were typically rare and self-limited, with recurrent inflammation being most common. Although both trabeculectomy with MMC and Ahmed valve implantation are reasonable surgical options in the management of uncontrolled uveitic glaucoma, Ahmed valve implantation was associated with higher cumulative success rate at 1 year and a longer mean time to failure.

  16. Hypertensive phase and early complications after Ahmed glaucoma valve implantation with intraoperative subtenon triamcinolone acetonide.

    Science.gov (United States)

    Turalba, Angela V; Pasquale, Louis R

    2014-01-01

    To evaluate intraoperative subtenon triamcinolone acetonide (TA) as an adjunct to Ahmed glaucoma valve (AGV) implantation. Retrospective comparative case series. Forty-two consecutive cases of uncontrolled glaucoma undergoing AGV implantation: 19 eyes receiving intraoperative subtenon TA and 23 eyes that did not receive TA. A retrospective chart review was performed on consecutive pseudophakic adult patients with uncontrolled glaucoma undergoing AGV with and without intraoperative subtenon TA injection by a single surgeon. Clinical data were collected from 42 eyes and analyzed for the first 6 months after surgery. Primary outcomes included intraocular pressure (IOP) and number of glaucoma medications prior to and after AGV implantation. The hypertensive phase (HP) was defined as an IOP measurement of greater than 21 mmHg (with or without medications) during the 6-month postoperative period that was not a result of tube obstruction, retraction, or malfunction. Postoperative complications and visual acuity were analyzed as secondary outcome measures. Five out of 19 (26%) TA cases and 12 out of 23 (52%) non-TA cases developed the HP (P=0.027). Mean IOP (14.2±4.6 in TA cases versus [vs] 14.7±5.0 mmHg in non-TA cases; P=0.78), and number of glaucoma medications needed (1.8±1.3 in TA cases vs 1.6±1.1 in the comparison group; P=0.65) were similar between both groups at 6 months. Although rates of serious complications did not differ between the groups (13% in the TA group vs 16% in the non-TA group), early tube erosion (n=1) and bacterial endophthalmitis (n=1) were noted with TA but not in the non-TA group. Subtenon TA injection during AGV implantation may decrease the occurrence of the HP but does not alter the ultimate IOP outcome and may pose increased risk of serious complications within the first 6 months of surgery.

  17. Apparatus for securing structural tubes in nuclear reactor fuel assemblies

    International Nuclear Information System (INIS)

    Kerry, J.S.

    1987-01-01

    This patent describes a nuclear reactor fuel assembly having a structural tube with a predetermined inside diameter, a generally cylindrical insert of an axial length substantially smaller than the axial length of the structural tube and having a generally cylindrical passageway of a predetermined diameter smaller than the predetermined inside diameter for providing an effectively reduced inside diameter for the structural tube. The insert comprises: means, having an outside diameter approximately equal to the predetermined inside diameter, for coaxially centering the insert within the structural tube; forming lobes, operable when expanded to locally deform against the structural tube thereby locking the insert within the structural tube

  18. Outcomes of Ahmed Valve Implant Following a Failed Initial Trabeculotomy and Trabeculectomy in Refractory Primary Congenital Glaucoma

    Science.gov (United States)

    Dave, Paaraj; Senthil, Sirisha; Choudhari, Nikhil; Sekhar, Garudadri Chandra

    2015-01-01

    Purpose: The aim was to report the outcome of Ahmed glaucoma valve (AGV) (New World Medical, Inc., Rancho Cucamonga, CA, USA) implantation as a surgical intervention following an initial failed combined trabeculotomy + trabeculectomy (trab + trab) in refractory primary congenital glaucoma (RPCG). Materials and Methods: Retrospective chart review of 11 eyes of 8 patients who underwent implantation of AGV (model FP8) for RPCG between 2009 and 2011. Prior trab + trab had failed in all the eyes. Success was defined as an intraocular pressure (IOP) >5 and ≤ 18 mmHg during examination under anesthesia with or without medications and without serious complications or additional glaucoma surgery. Results: The mean age at AGV implantation was 15.4 ± 4.9 months. The mean preoperative IOP was 28 ± 5.7 mmHg which reduced to 13.6 ± 3.4 mmHg postoperatively at the last follow-up (P < 0.0001). The number of topical antiglaucoma medications reduced from a mean of 2.6 ± 0.5 to 1.6 ± 0.9 postoperatively (P = 0.009). The definition of qualified success was met in 10 (90%) eyes. One eye developed a shallow anterior chamber with choroidal detachment at 1-week, which resolved spontaneously with medications. None of the eyes developed a hypertensive phase. One eye had a long tube resulting in tube corneal touch that required trimming of the tube. One eye developed tube retraction, which was treated with a tube extender. The mean follow-up was 17.9 ± 9.3 (6.2-35.4) months. Conclusion: Managing RPCG remains a challenge. AGV implant was successful in a significant proportion of cases. PMID:25624676

  19. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction...... relative to the rod element so as to allow for a fluid flow in the tube through the first valve member, along the rod element, and through the second valve member. The tube comprises an at least partly flexible tube portion between the valve members such that a repeated deformation of the flexible tube...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...

  20. Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure.

    Science.gov (United States)

    Huang, Jingjing; Lin, Jialiu; Wu, Ziqiang; Xu, Hongzhi; Zuo, Chengguo; Ge, Jian

    2015-01-01

    The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve (AGV) implantation in patients less than 7 years of age, with advanced primary congenital glaucoma who have failed previous surgeries. Consecutive patients with advanced primary congenital glaucoma that failed previous operations and had undergone subsequent AGV implantation were evaluated retrospectively. Surgical success was defined as 1) intraocular pressure (IOP) ≥6 and ≤21 mmHg; 2) IOP reduction of at least 30% relative to preoperative values; and 3) without the need for additional surgical intervention for IOP control, loss of light perception, or serious complications. Fourteen eyes of eleven patients were studied. Preoperatively, the average axial length was 27.71±1.52 (25.56-30.80) mm, corneal diameter was 14.71±1.07 (13.0-16.0) mm, cup-to-disc ratio was 0.95±0.04 (0.9-1.0), and IOP was 39.5±5.7 (30-55) mmHg. The mean follow-up time was 18.29±10.96 (5-44, median 18) months. There were significant reductions in IOPs and the number of glaucoma medications (Pvalve success were 85.7%, 71.4%, and 71.4% at 6, 12, and 18 months, respectively. Severe surgical complications, including erosion of tube, endophthalmitis, retinal detachment, choroidal detachment, and delayed suprachoroidal hemorrhage, occurred in 28.6% cases. AGV implantation remains a viable option for patients with advanced primary congenital glaucoma unresponsive to previous surgical intervention, despite a relatively high incidence of severe surgical complications.

  1. Glaucoma in modified osteo-odonto-keratoprosthesis eyes: role of additional stage 1A and Ahmed glaucoma drainage device-technique and timing.

    Science.gov (United States)

    Iyer, Geetha; Srinivasan, Bhaskar; Agarwal, Shweta; Shetty, Roshni; Krishnamoorthy, Sripriya; Balekudaru, Shantha; Vijaya, Lingam

    2015-03-01

    To report the technique, timing, and outcomes of the Ahmed glaucoma drainage device in eyes with the modified osteo-odonto-keratoprosthesis (MOOKP) and the role of an additional stage 1A to the Rome-Vienna protocol. Retrospective interventional case series. Case records of 22 eyes of 20 patients with high intraocular pressure at various stages of the MOOKP procedure performed in 85 eyes of 82 patients were studied. Stage 1A, which includes total iridodialysis, intracapsular cataract extraction, and anterior vitrectomy, was done in all eyes as the primary stage. Seventeen Ahmed glaucoma drainage devices were implanted in 15 eyes of 14 patients (chemical injury in 9 [10 eyes] and Stevens-Johnson syndrome in 5 patients). Implantation was performed during and after stage 1A in 2 and 7 eyes, respectively, after stage 1B+1C in 1 eye, and after stage 2 in 6 eyes. Eleven of 15 eyes (73.3%) remained stable with adequate control of intraocular pressure over a mean follow-up period of 33.68 months (1-90 months). Complications related to the drainage device were hypotony in 1 eye and vitreous block of the tube in 1 eye. It is ideal to place the Ahmed glaucoma drainage device prior to the mucosal graft when the anatomy of the ocular surface is least altered with best outcomes. The technique of placement of the drainage device during the various stages of the MOOKP procedure has been described. The intraocular pressure stabilized in three quarters of the eyes with pre-existing glaucoma. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Use of subconjunctival injections of 5-fluorouracil to rescue and prolong intraocular pressure reduction for a failing Ahmed glaucoma implant.

    Science.gov (United States)

    Kaplowitz, Kevin; Khodadadeh, Sarah; Wang, Samantha; Lee, Daniel; Tsai, James C

    2017-06-01

    5-Fluorouracil (5-FU) has been well described for a failing trabeculectomy bleb, but not for aqueous shunts. We sought to determine whether subconjunctival 5-FU prolongs the intraocular pressure (IOP) efficacy of Ahmed shunts. We included all patients with Ahmed FP-7 implantation by one surgeon at Yale University. Patients with  21 on >2 medications. Five-milligram (0.1 cc) injections were made over the plate. The control group consisted of Ahmed FP-7 patients without injections. The main outcome measure was IOP. Secondary outcome was success (IOP Ahmed shunts. Outcomes between eyes receiving injections and controls were statistically similar.

  3. Excisional Bleb Revision for Management of Failed Ahmed Glaucoma Valve.

    Science.gov (United States)

    Eslami, Yadollah; Fakhraie, Ghasem; Moghimi, Sasan; Zarei, Reza; Mohammadi, Masoud; Nabavi, Amin; Yaseri, Mehdi; Izadi, Ali

    2017-12-01

    To evaluate the outcome of excisonal bleb revision in patients with failed Ahmed glaucoma valve (AGV). In total, 29 patients with uncontrolled intraocular pressure (IOP) despite of maximal tolerated medical therapy at least 6 months after AGV implantation were enrolled in this prospective interventional case series. Excision of fibrotic tissue around the reservoir with application of mitomycin C 0.02% was performed. IOP, number of glaucoma medications were evaluated at baseline and 1 week and 1, 3, 6, and 12 months postoperatively. Complete and qualified success was defined as IOP≤21 mm Hg with or without glaucoma medications, respectively. Intraoperative and postopervative complications were also recorded. Mean IOP was reduced from 30±4.2 mm Hg at baseline to 19.2±3.1 mm Hg at 12-month follow-up visit (Pglaucoma medications was decrease from 3.2±0.5 at baseline to 1.9±0.7 at 12-month follow-up (Pglaucoma surgeries were significantly associated with the failure of excisonal bleb revision. Excisional bleb revision could be considered as a relatively effective alternative option for management of inadequate IOP control after AGV implantation.

  4. Ahmed glaucoma valve in eyes with preexisting episcleral encircling element.

    Science.gov (United States)

    Choudhari, Nikhil Shreeram; George, Ronnie; Shantha, Balekudaru; Neog, Aditya; Tripathi, Shweta; Srinivasan, Bhaskar; Vijaya, Lingam

    2014-05-01

    To describe the use of Ahmed glaucoma valve (AGV) in the management of intractable glaucoma in eyes with a preexisting episcleral encircling element. This is a retrospective, consecutive, noncomparative study. The study included 12 eyes of 12 patients with a preexisting episcleral encircling element that underwent implantation of silicone AGV to treat intractable glaucoma during January 2009 to September 2010. The mean patient age was 25.6 (standard deviation 17.1) years. Five (41.6%) patients were monocular. The indications for AGV were varied. The mean duration between placement of episcleral encircling element and implantation of AGV was 30.5 (33.8) months. The mean follow-up was 37.4 (22.9) weeks. Preoperatively, the mean intraocular pressure (IOP) was 31.4 (7.9) mmHg and the mean antiglaucoma medications were 2.8. At the final postoperative follow-up, the mean IOP was 12.5 (3.5) mmHg and the mean number of antiglaucoma medications was 0.8 (P glaucoma in eyes with a preexisting episcleral encircling element keeping in mind the possibility of significant postoperative complications.

  5. A microinvasive technique for management of corneal edema secondary to glaucoma drainage device tube-corneal touch

    Directory of Open Access Journals (Sweden)

    Harsh Kumar

    2018-01-01

    Full Text Available We present a case of tube endothelial touch where a suture technique for repositioning of the Ahmed glaucoma valve was performed. Advantage of this technique is that it is minimally invasive and anterior chamber stability is maintained during the procedure.

  6. Lattice insertions for POPAE

    International Nuclear Information System (INIS)

    Cho, Y.; Crosbie, E.A.; Diebold, R.; Johnson, D.E.; Ohnuma, S.; Ruggiero, A.G.; Teng, L.C.

    1977-01-01

    Four types of insertions are described for the six 200-m straight sections of POPAE. All have dispersion matched to zero. (1) Injection-ejection insertion--This has proper high-β values and phase advances for horizontal injection and vertical ejection. (2) Phase-adjust insertion--The phase advance in this insertion is adjustable over a range of approximately 100 0 . (3) General-purpose insertion--The β* is adjustable from 2.5. to 200 m and the crossing angle is adjustable from 0 to 11 mrad. (4) High-luminosity insertion--This gives an even lower β + of meter

  7. Enhancement of heat transfer using varying width twisted tape inserts

    African Journals Online (AJOL)

    International Journal of Engineering, Science and Technology ... experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of varying width twisted tape inserts with air as the working fluid.

  8. Long-term results of Ahmed glaucoma valve implantation in Egyptian population.

    Science.gov (United States)

    Elhefney, Eman; Mokbel, Tharwat; Abou Samra, Waleed; Kishk, Hanem; Mohsen, Tarek; El-Kannishy, Amr

    2018-01-01

    To evaluate the long-term results and complications of Ahmed glaucoma valve (AGV) implantation in a cohort of Egyptian patients. A retrospective study of 124 eyes of 99 patients with refractory glaucoma who underwent AGV implantation and had a minimum follow-up of 5y was performed. All patients underwent complete ophthalmic examination and intraocular pressure (IOP) measurement before surgery and at 1d, weekly for the 1 st month, 3, 6mo, and 1y after surgery and yearly afterward for 5y. IOP was measured by Goldmann applanation tonometry and/or Tono-Pen. Complications and the number of anti-glaucoma medications needed were recorded. Success was defined as IOP less than 21 mm Hg with or without anti-glaucoma medication and without additional glaucoma surgery. Mean age was 23.1±19.9y. All eyes had at least one prior glaucoma surgery. IOP was reduced from a mean of 37.2±6.8 to 19.2±5.2 mm Hg after 5y follow-up with a reduced number of medications from 2.64±0.59 to 1.81±0.4. Complete and qualified success rates were 31.5% and 46.0% respectively at the end of follow-up. The most common complications were encapsulated cyst formation in 51 eyes (41.1%), complicated cataract in 9 eyes (7.25%), recessed tube in 8 eyes (6.45%), tube exposure in 6 eyes (4.8%) and corneal touch in 6 eyes (4.8%). Other complications included extruded AGV, endophthalmitis and persistent hypotony. Each of them was recorded in only 2 eyes (1.6%). Although refractory glaucoma is a difficult problem to manage, AGV is effective and relatively safe procedure in treating refractory glaucoma in Egyptian patients with long-term follow-up. Encapsulated cyst formation was the most common complication, which limits successful IOP control after AGV implantation. However, effective complications management can improve the rate of success.

  9. Long-term results of Ahmed glaucoma valve implantation in Egyptian population

    Directory of Open Access Journals (Sweden)

    Eman Elhefney

    2018-03-01

    Full Text Available AIM: To evaluate the long-term results and complications of Ahmed glaucoma valve (AGV implantation in a cohort of Egyptian patients. METHODS: A retrospective study of 124 eyes of 99 patients with refractory glaucoma who underwent AGV implantation and had a minimum follow-up of 5y was performed. All patients underwent complete ophthalmic examination and intraocular pressure (IOP measurement before surgery and at 1d, weekly for the 1st month, 3, 6mo, and 1y after surgery and yearly afterward for 5y. IOP was measured by Goldmann applanation tonometry and/or Tono-Pen. Complications and the number of anti-glaucoma medications needed were recorded. Success was defined as IOP less than 21 mm Hg with or without anti-glaucoma medication and without additional glaucoma surgery. RESULTS: Mean age was 23.1±19.9y. All eyes had at least one prior glaucoma surgery. IOP was reduced from a mean of 37.2±6.8 to 19.2±5.2 mm Hg after 5y follow-up with a reduced number of medications from 2.64±0.59 to 1.81±0.4. Complete and qualified success rates were 31.5% and 46.0% respectively at the end of follow-up. The most common complications were encapsulated cyst formation in 51 eyes (41.1%, complicated cataract in 9 eyes (7.25%, recessed tube in 8 eyes (6.45%, tube exposure in 6 eyes (4.8% and corneal touch in 6 eyes (4.8%. Other complications included extruded AGV, endophthalmitis and persistent hypotony. Each of them was recorded in only 2 eyes (1.6%. CONCLUSION: Although refractory glaucoma is a difficult problem to manage, AGV is effective and relatively safe procedure in treating refractory glaucoma in Egyptian patients with long-term follow-up. Encapsulated cyst formation was the most common complication, which limits successful IOP control after AGV implantation. However, effective complications management can improve the rate of success.

  10. Expanded polytetrafluoroethylene membrane alters tissue response to implanted Ahmed glaucoma valve.

    Science.gov (United States)

    DeCroos, Francis Char; Ahmad, Sameer; Kondo, Yuji; Chow, Jessica; Mordes, Daniel; Lee, Maria Regina; Asrani, Sanjay; Allingham, R Rand; Olbrich, Kevin C; Klitzman, Bruce

    2009-07-01

    Long-term intraocular pressure control by glaucoma drainage implants is compromised by the formation of an avascular fibrous capsule that surrounds the glaucoma implant and increases aqueous outflow resistance. It is possible to alter this fibrotic tissue reaction and produce a more vascularized and potentially more permeable capsule around implanted devices by enclosing them in a porous membrane. Ahmed glaucoma implants modified with an outer 5-microm pore size membrane (termed porous retrofitted implant with modified enclosure or PRIME-Ahmed) and unmodified glaucoma implants were implanted into paired rabbit eyes. After 6 weeks, the devices were explanted and subject to histological analysis. A tissue response containing minimal vascularization, negligible immune response, and a thick fibrous capsule surrounded the unmodified Ahmed glaucoma implant. In comparison, the tissue response around the PRIME-Ahmed demonstrated a thinner fibrous capsule (46.4 +/- 10.8 microm for PRIME-Ahmed versus 94.9 +/- 21.2 microm for control, p vascularized near the tissue-material interface. A prominent chronic inflammatory response was noted as well. Encapsulating the aqueous outflow pathway with a porous membrane produces a more vascular tissue response and thinner fibrous capsule compared with a standard glaucoma implant plate. Enhanced vascularity and a thinner fibrous capsule may reduce aqueous outflow resistance and improve long-term glaucoma implant performance.

  11. Technique employed to seal a tube leaking in a heat exchanger of the tube type by explosives with supporting means for the adjacent tubes

    International Nuclear Information System (INIS)

    Larson, G.C.

    1978-01-01

    This invention concerns the technique employed to seal a tube leaking in a heat exchanger of the tube and tube plate type by detonating metal plugs activated by an explosive and inserted in both ends of the tube. It refers in particular to an apparatus and process in which the deformation or distortion of the adjacent tubes and tube plate ties under the effect of the explosive forces is significantly reduced [fr

  12. Delayed-onset streptococcus pyogenes endophthalmitis following Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Bayraktar, Zerrin; Kapran, Ziya; Bayraktar, Sükrü; Acar, Nur; Unver, Yaprak Banu; Gök, Kemran

    2005-01-01

    To report a case of delayed-onset Streptococcus pyogenes endophthalmitis following implantation of an Ahmed glaucoma valve. A 10-year-old patient presented with acute endophthalmitis 1 year after Ahmed glaucoma valve implantation. The conjunctiva and Tenon's capsule over the valve plate had been penetrated by one of the polypropylene fixation sutures. The valve was removed, and pars plana vitrectomy was performed. Vitreous specimens and removal of the discharge over the plate revealed Streptococcus pyogenes. This is the first documented case of Streptococcus pyogenes endophthalmitis following Ahmed glaucoma valve implantation. We think the conjunctival buttonhole caused by the polypropylene suture provided an entry site for the infection. (c) Japanese Ophthalmological Society 2005.

  13. Evaluation of success after second Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Nilforushan, Naveed; Yadgari, Maryam; Jazayeri, Anis Alsadat; Karimi, Nasser

    2016-03-01

    To evaluate the outcome of the second Ahmed glaucoma valve (AGV) surgery in eyes with failed previous AGV surgery. Retrospective case series. Following chart review, 36 eyes of 34 patients with second AGV implantation were enrolled in this study. The primary outcome measure was surgical success defined in terms of intraocular pressure (IOP) control using two criteria: Success was defined as IOP ≤21 mmHg (criterion 1) and IOP ≤16 mmHg (criterion 2), with at least 20% reduction in IOP, either with no medication (complete success) or with no more than two medications (qualified success). Kaplan-Meier survival analysis was used to determine the probability of surgical success. The average age of the patients was 32.7 years (range 4-65), and the mean duration of follow-up was 21.4 months (range 6-96). Preoperatively, the mean IOP was 26.94 mmHg (standard deviation [SD] 7.03), and the patients were using 2.8 glaucoma medications on average (SD 0.9). The mean IOP decreased significantly to 13.28 mmHg (SD 3.59) at the last postoperative visit (P = 0.00) while the patients needed even fewer glaucoma medications on average (1.4 ± 1.1, P = 0.00). Surgical success of second glaucoma drainage devices (Kaplan-Meier analysis), according to criterion 1, at 6, 12, 18, and 42 months was 94%, 85%, 80%, and 53% respectively, and according to criterion 2, was 94%, 85%, 75%, and 45%, respectively. Repeated AGV implantation seems to be a safe modality of treatment with acceptable success rate in cases with failed previous AGV surgery.

  14. The effect of intravitreal bevacizumab injection before Ahmed valve implantation in patients with neovascular glaucoma.

    Science.gov (United States)

    Kang, Jung Youb; Nam, Ki Yup; Lee, Sang Joon; Lee, Seung Uk

    2014-08-01

    To evaluate the effect of intravitreal bevacizumab (IVB) before Ahmed valve implantation for treatment of neovascular glaucoma (NVG). This study is a retrospective, comparative, consecutive case series. The study group consisted of 27 eyes of 26 patients with NVG who underwent an Ahmed valve implantation. Thirteen eyes were treated with Ahmed valve implantation alone (control group), and 14 eyes were treated with a combination of preoperative IVB injection and Ahmed valve implantation (IVB group). Visual acuity, intraocular pressure (IOP), number of anti-glaucoma medications, surgical complications, and success rate were compared between the two groups. There were no significant differences in preoperative characteristics between the two groups. Visual acuity at 1, 2 weeks, and 1 month after surgery were significantly better in the IVB group (p = 0.038, 0.034, and 0.032, respectively). Hyphema associated with Ahmed valve implantation occurred significantly less in the IVB group (p = 0.016). On the other hand, the mean IOP and number of anti-glaucoma medications at all follow-up periods were similar between the two groups. Kaplan-Meier survival analysis showed the probability of success 6 months after surgery as 71.4 % in the IVB group and 84.6 % in the control group. No significant difference in success rate was found between the groups (p = 0.422). IVB before Ahmed valve implantation for treatment of NVG reduced the incidence of hyphema. In this retrospective study, IVB provided better visual outcome in the early postoperative periods but did not significantly improve mean IOP, number of anti-glaucoma medications, or success rate.

  15. A retrospective study on the outcomes of Ahmed valve versus Ahmed valve combined with fluocinolone implant in uveitic glaucoma.

    Science.gov (United States)

    Sevgi, Duriye D; Davoudi, Samaneh; Talcott, Katherine E; Cho, Heeyoon; Guo, Rong; Lobo, Ann-Marie; Papaliodis, George N; Turalba, Angela; Sobrin, Lucia; Shen, Lucy Q

    2017-01-01

    To compare the intraocular pressure (IOP) outcomes of Ahmed glaucoma valve (AGV) surgery alone versus AGV with fluocinolone implant in uveitic glaucoma patients. We identified uveitic glaucoma patients with AGV surgery alone and AGV surgery combined with fluocinolone implant from the Massachusetts Eye and Ear Ocular Inflammation Database. Demographic information, visual acuity, and IOP were recorded at preoperative visits and 1, 6, and 12 months after surgery. Incidence of hypertensive phase, defined as an IOP of >21 mm Hg or use of additional treatment to lower IOP occurring any time between 7 days to 6 months postoperatively, was investigated. Multilevel mixed effects models were performed to compare the outcomes between groups. Eighteen eyes of 13 uveitic glaucoma patients with 1-year follow-up data were included. There were 11 eyes of 9 patients (mean age, 56.5 years; 63.6% male) in the AGV group and 7 eyes of 4 patients (mean age, 61.3 years; 71.4% male) in the AGV + fluocinolone group. There was no significant difference in visual acuity change at 1 year after surgery between groups ( P = 0.25), although visual acuity improvement was significant in the AGV group ( P = 0.01). The hypertensive phase occurred in 91% of AGV patients and 43% of AGV + fluocinolone patients ( P = 0.30), with onset of 8-40 days (mean, 18 days) after surgery. IOP and number of glaucoma medications decreased at the 1-year postoperative visits in both the AGV group ( P glaucoma medications (0.28 vs 1.30 [ P = 0.01]) and had better inflammation control ( P = 0.02). The surgical complication rates were similar between groups. In uveitic glaucoma, AGV with fluocinolone achieves a similar, desired IOP control but with fewer glaucoma medications than AGV alone.

  16. Hand-actuated spring clip insertion tool

    International Nuclear Information System (INIS)

    Cuba, G.W.

    1993-01-01

    A hand-actuated insertion tool includes a handle assembly, an elongated hollow tubular outer support tube, an elongated inner pull rod, and a coupling arrangement. The handle assembly has a first handle member and a second handle member pivoted to a member for movement between unactuated and actuated positions. The tube is attached in a fixed relation to a handle member. The rod is mounted within the tube for sliding movement relative thereto between home and retracted positions. The coupling arrangement pivotally connects the rod to the second handle member such that the rod will undergo sliding movement from the home position to the retracted positions relative to the tube as the second handle member is moved from the unactuated position to the actuated position adjacent to the first handle member. (author)

  17. Early Ahmed glaucoma valve implantation after penetrating keratoplasty leads to better outcomes in an Asian population with preexisting glaucoma.

    Directory of Open Access Journals (Sweden)

    Ming-Cheng Tai

    Full Text Available BACKGROUND: To evaluate the efficacy of Ahmed Glaucoma Valve (AGV surgery and the optimal interval between penetrating keratoplasty (PKP and AGV implantation in a population of Asian patients with preexisting glaucoma who underwent PKP. METHODOLOGY/PRINCIPAL FINDINGS: In total, 45 eyes of 45 patients were included in this retrospective chart review. The final intraocular pressures (IOPs, graft survival rate, and changes in visual acuity were assessed to evaluate the outcomes of AGV implantations in eyes in which AGV implantation occurred within 1 month of post-PKP IOP elevation (Group 1 and in eyes in which AGV implantation took place more than 1 month after the post-PKP IOP evaluation (Group 2. Factors that were associated with graft failure were analyzed, and the overall patterns of complications were reviewed. By their final follow-up visits, 58% of the patients had been successfully treated for glaucoma. After the operation, there were no statistically significant differences between the groups with respect to graft survival (p = 0.98, but significant differences for IOP control (p = 0.049 and the maintenance of visual acuity (VA (p21 mm Hg. The most common surgical complication, aside from graft failure, was hyphema. CONCLUSIONS/SIGNIFICANCE: Early AGV implantation results in a higher probability of AGV survival and a better VA outcome without increasing the risk of corneal graft failure as a result of post-PKP glaucoma drainage tube implantation.

  18. Early Ahmed Glaucoma Valve Implantation after Penetrating Keratoplasty Leads to Better Outcomes in an Asian Population with Preexisting Glaucoma

    Science.gov (United States)

    Tai, Ming-Cheng; Chen, Yi-Hao; Cheng, Jen-Hao; Liang, Chang-Min; Chen, Jiann-Torng; Chen, Ching-Long; Lu, Da-Wen

    2012-01-01

    Background To evaluate the efficacy of Ahmed Glaucoma Valve (AGV) surgery and the optimal interval between penetrating keratoplasty (PKP) and AGV implantation in a population of Asian patients with preexisting glaucoma who underwent PKP. Methodology/Principal Findings In total, 45 eyes of 45 patients were included in this retrospective chart review. The final intraocular pressures (IOPs), graft survival rate, and changes in visual acuity were assessed to evaluate the outcomes of AGV implantations in eyes in which AGV implantation occurred within 1 month of post-PKP IOP elevation (Group 1) and in eyes in which AGV implantation took place more than 1 month after the post-PKP IOP evaluation (Group 2). Factors that were associated with graft failure were analyzed, and the overall patterns of complications were reviewed. By their final follow-up visits, 58% of the patients had been successfully treated for glaucoma. After the operation, there were no statistically significant differences between the groups with respect to graft survival (p = 0.98), but significant differences for IOP control (p = 0.049) and the maintenance of visual acuity (VA) (pglaucoma, a history of previous PKP, and a preoperative IOP that was >21 mm Hg. The most common surgical complication, aside from graft failure, was hyphema. Conclusions/Significance Early AGV implantation results in a higher probability of AGV survival and a better VA outcome without increasing the risk of corneal graft failure as a result of post-PKP glaucoma drainage tube implantation. PMID:22629464

  19. 21 CFR 888.4230 - Cement ventilation tube.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  20. Outcomes of Ahmed Glaucoma Valve Revision in Pediatric Glaucoma.

    Science.gov (United States)

    Al-Omairi, Ahmed Mansour; Al Ameri, Aliah H; Al-Shahwan, Sami; Khan, Arif O; Al-Jadaan, Ibrahim; Mousa, Ahmed; Edward, Deepak P

    2017-11-01

    Encapsulation of the Ahmed glaucoma valve (AGV) plate is a common cause for postoperative elevation of intraocular pressure, especially in children. Many reports have described the outcomes of AGV revision in adults. However, the outcomes of AGV revision in children are poorly documented. The aim of this study was to determine the outcomes of AGV revision in children. Retrospective cross-sectional study. A retrospective chart review of patients less than 15 years of age who underwent AGV revision with a minimum postoperative follow-up of 6 months was conducted. Outcome measures included reduction in intraocular pressure from baseline, survival analysis, and reduction in the number of antiglaucoma medications. Postoperative complications were also noted. Complete success was defined as an IOP of 21 mm Hg or less without medications, while qualified success was defined as having an IOP of 21 mm Hg or less with medications. A total of 44 eyes met the inclusion criteria. Primary congenital glaucoma was present in 39 eyes (88.6%), aphakic glaucoma in 4 eyes (9.1%), and Peters anomaly-associated glaucoma in 1 eye (2.3%). The mean number of previous surgeries was 1.4, and the mean age was 6.7 years (range, 1.9-13 years) with a median follow-up of 12 months (range, 6-24 months). The IOP was reduced from a preoperative mean of 30.4 (± 10.3) to 24.9 (± 10.6) mm Hg at 6 months postoperatively. Kaplan-Meier analysis showed that the complete success rate at 1 month was 100% followed by a rapid decline at 6 months to 38.6%, 27.7% at 1 year, and 5.5% at 2 years. Qualified success rate was 100% at 1 month followed by a 6-month and 1-year survival rate of approximately 50% and a 2-year survival rate of approximately 16%. The median survival time was 14 months. No specific risk factors for failure were identified. Visual acuity remained unchanged following revision. The most common complication was recurrence of encapsulation with elevated IOP (15.9%). Other

  1. The use of radioactive inserts in the study of metal deformation during tube-making processes; Emploi de fils metalliques radioactifs pour l'etude des deformations des metaux pendant la fabrication de tubes; Ispol'zovanie radioaktivnykh vtulok dlya izucheniya deformatsii metallov pri protsesse izgotovleniya trub; Empleo de insertos radiactivos en el estudio de la deformacion de los metales durante la fabricacion de tubos

    Energy Technology Data Exchange (ETDEWEB)

    Davison, W H.T. [Tube Investments Research Laboratories, Cambridge (United Kingdom)

    1962-01-15

    This paper reports on the use of radioactive inserts in studying the deformation of steel in hot rotary piercing for tube making. Iron or steel wires are activated in the pile, inserted in tubes drilled in iron or steel billets, which are then processed under normal production conditions. Careful monitoring shows that the radiation exposures and contamination of the plant are quite negligible. On cooling, the billets are scanned in the laboratory, using a collimated scintillationcounter mounted normal to the surface of the pierced billet, and isodose curves show the shape of the deformed insert normal to the tube surface. A similar scan of a section normal to the axis of the tube gives a second plot; from a combination of the two plots, a three-dimensional picture is obtained. Some results are quoted, but the main emphasis of the paper is on the experimental technique, which has quite general applicability to metal deformation studies. The insert must be located within a millimeter or thereabouts, for which a higher resolution is required than is normal in medical scanning techniques. The problems of achieving this are discussed in terms of {gamma}-energy, collimator design and energy discrimination. (author) [French] Le present memoire traite de l'emploi de fils metalliques radioactifs pour l'etude de la deformation de l'acier durant le forage rotatif a chaud en vue de la fabrication des tubes. Des fils de fer ou d'acier sont actives dans un reacteur et places dans des cavites tabulaires menagees a l'interieur de billettes de fer ou d'acier que l'on transforme ensuite dans les conditions de fabrication normales. Un controle radiologique minutieux montre que les dangers d'irradiation et de contamination dans l'usine sont pratiquement negligeables. Apres refroidissement, les billettes sont examinees en laboratoire au moyen d'un compteur a scintillations avec collimateur de faible ouverture, monte de facon que l'axe soit perpendiculaire a la surface de la billette

  2. Supra-Tenon Capsule Implantation of the Ahmed Glaucoma Valve in Refractory Pediatric Glaucoma.

    Science.gov (United States)

    Elhefney, Eman M; Al-Sharkawy, Hossam T; Kishk, Hanem M

    2016-09-01

    To evaluate the efficacy of supra-Tenon capsule implantation of an Ahmed glaucoma valve (AGV) as a measure to decrease the fibrotic potential of the Tenon capsule on bleb formation and its subsequent effect on intraocular pressure (IOP) control in children with refractory glaucoma. Mansoura Ophthalmic Centre, Faculty of Medicine, Mansoura University, Egypt. A prospective interventional study. Twenty-two eyes of 12 children with refractory glaucoma underwent supra-Tenon capsule implantation of AGV. Ophthalmic examinations under general anesthesia including measurement of the corneal diameter and the IOP with Perkin's tonometer were performed preoperatively, on the first postoperative day, the first postoperative week, weekly for the first month, 2-weekly for the following 3 months, and monthly for at least 18 months. Postoperative complications and the number of glaucoma medications used preoperatively and postoperatively were recorded. The paired Student t test was used to compare preoperative and postoperative data. There were 12 eyes (54.6%) with refractory congenital glaucoma, 7 eyes (31.8%) with refractory pseudophakic glaucoma, and 3 eyes (13.6%) with refractory aphakic glaucoma. Patients included 10 male (83.3%) and 2 female (16.7%) children with a mean age of 16.3±9.7 months. The mean follow-up duration was 24.1±4.3 months. There was a statistically significant difference between the mean preoperative IOP (30.7±2.88 mm Hg) and the mean postoperative IOP (16.1±3.60 mm Hg) (t=16.22 and P=0.000, with a mean decrease in the IOP by 47.6%). The difference between the mean number of antiglaucoma medications before surgery (1.86±0.4) and after surgery (1.0±0.9) was also statistically significant (t=4.31 and P=0.000). Total success was achieved in 18 eyes (81.9%). Postoperative complications included tube exposure and slippage (10%), hypotony (10%), and hyphema (5%). Supra-Tenon capsule implantation of the AGV was successful in controlling the IOP with few

  3. Surgical results of trabeculectomy and Ahmed valve implantation following a previous failed trabeculectomy in primary congenital glaucoma patients.

    Science.gov (United States)

    Lee, Naeun; Ma, Kyoung Tak; Bae, Hyoung Won; Hong, Samin; Seong, Gong Je; Hong, Young Jae; Kim, Chan Yun

    2015-04-01

    To compare the surgical results of trabeculectomy and Ahmed glaucoma valve implantation after a previous failed trabeculectomy. A retrospective comparative case series review was performed on 31 eye surgeries in 20 patients with primary congenital glaucoma who underwent trabeculectomy or Ahmed glaucoma valve implantation after a previous failed trabeculectomy with mitomycin C. The preoperative mean intraocular pressure was 25.5 mmHg in the trabeculectomy group and 26.9 mmHg in the Ahmed glaucoma valve implantation group (p = 0.73). The 48-month postoperative mean intraocular pressure was 19.6 mmHg in the trabeculectomy group and 20.2 mmHg in the Ahmed glaucoma valve implantation group (p = 0.95). The 12-month trabeculectomy success rate was 69%, compared with 64% for Ahmed glaucoma valve implantation, and the 48-month success rates were 42% and 36% for trabeculectomy and valve implantation, respectively. The success rates following the entire follow-up period were not significantly different between the two groups (p > 0.05 by log rank test). Postoperative complications occurred in 25% of the trabeculectomy-operated eyes and 9% of the Ahmed-implanted eyes (p = 0.38). There was no significant difference in surgical outcome between the trabeculectomy and Ahmed glaucoma valve implantation groups, neither of which had favorable results. However, the trabeculectomy group demonstrated a higher prevalence of adverse complications such as post-operative endophthalmitis.

  4. Book featuring Grand Egyptian Museum design proposals by Ahmed Ali published

    OpenAIRE

    Chadwick, Heather Riley

    2009-01-01

    "Silence, Darkness and Light," a new book by Ahmed K. Ali, adjunct professor of architecture in the School of Architecture + Design and program leader for study abroad in Egypt for Virginia Tech's College of Architecture and Urban Studies, has been published by VDM Verlag in Saarbrucken, Germany.

  5. Surgical Outcome of Ahmed Valve Implantation in Mexican Patients with Neovascular Glaucoma.

    Science.gov (United States)

    Hernandez-Oteyza, Alejandra; Lazcano-Gomez, Gabriel; Jimenez-Roman, Jesus; Hernandez-Garciadiego, Carlos

    2014-01-01

    To describe clinical results of Ahmed glaucoma valve implantation in Mexican patients with neovascular glaucoma (NVG). We reviewed records of 60 eyes of 60 patients with NVG who underwent Ahmed valve implantation, with a follow-up period of 1 year. We identified successful and failed cases and compared baseline and follow-up characteristics to identify possible differences between both groups. We classified 36 eyes (60%) as successful and 24 (40%) as failed cases. We found a significant difference in success rate in patients who had a hypertensive phase at any time during the follow-up period (OR = 5.15, CI = 1.49-20.15, p = 0.004). Patients in the success group showed a statistically significant decrease in the number of glaucoma medications 1 year after surgery (p Ahmed valve surgical failure in patients with NVG. How to cite this article: Hernandez-Oteyza A, Lazcano-Gomez G, Jimenez-Roman J, Hernandez-Garciadiego C. Surgical Outcome of Ahmed Valve Implantation in Mexican Patients with Neovascular Glaucoma. J Curr Glaucoma Pract 2014;8(3):86-90.

  6. Bilateral Sturge-Weber Syndrome and glaucoma controlled with Ahmed valve implant

    Directory of Open Access Journals (Sweden)

    Marcelo Jarczun Kac

    2015-02-01

    Full Text Available Sturge-Weber Syndrome is a rare neuro-oculocutaneous disorder. The authors describe the case of a 13 years old boy, presented with bilateral Sturge-Weber Syndrome and glaucoma. Surgical treatment with Ahmed valve implantation in both eyes was carried out achieving lower levels of intraocular pressure.

  7. Gastrostomy Tube (G-Tube)

    Science.gov (United States)

    ... any of these problems: a dislodged tube a blocked or clogged tube any signs of infection (including redness, swelling, or warmth at the tube site; discharge that's yellow, green, or foul-smelling; fever) excessive bleeding or drainage from the tube site severe abdominal pain lasting ...

  8. Follow-up of the original cohort with the Ahmed glaucoma valve implant.

    Science.gov (United States)

    Topouzis, F; Coleman, A L; Choplin, N; Bethlem, M M; Hill, R; Yu, F; Panek, W C; Wilson, M R

    1999-08-01

    To study the long-term results of the Ahmed glaucoma valve implant in patients with complicated glaucoma in whom short-term results have been reported. In this multicenter study, we analyzed the long-term outcome of a cohort of 60 eyes from 60 patients in whom the Ahmed glaucoma valve was implanted. Failure was characterized by at least one of the following: intraocular pressure greater than 21 mm Hg at both of the last two visits less than 6 mm Hg at both of the last two visits, loss of light perception, additional glaucoma surgery, devastating complications, and removal or replacement of the Ahmed glaucoma valve implant. Devastating complications included chronic hypotony, retinal detachment, malignant glaucoma, endophthalmitis, and phthisis bulbi; we also report results that add corneal complications (corneal decompensation or edema, corneal graft failure) as defining a devastating complication. The mean follow-up time for the 60 eyes was 30.5 months (range, 2.1 to 63.5). When corneal complications were included in the definition of failure, 26 eyes (43%) were considered failures. Cumulative probabilities of success at 1, 2, 3, and 4 years were 76%, 68%, 54%, and 45%, respectively. When corneal complications were excluded from the definition of failure, 13 eyes (21.5%) were considered failures. Cumulative probabilities of success at 1, 2, 3, and 4 years were 87%, 82%, 76%, and 76%, respectively. Most of the failures after 12 months of postoperative follow-up were because of corneal complications. The long-term performance of the Ahmed glaucoma valve implant is comparable to other drainage devices. More than 12 months after the implantation of the Ahmed glaucoma valve implant, the most frequent adverse outcome was corneal decompensation or corneal graft failure. These corneal problems may be secondary to the type of eyes that have drainage devices or to the drainage device itself. Further investigation is needed to identify the reasons that corneal problems

  9. Pressure tube reactor

    International Nuclear Information System (INIS)

    Seki, Osamu; Kumasaka, Katsuyuki.

    1988-01-01

    Purpose: To remove the heat of reactor core using a great amount of moderators at the periphery of the reactor core as coolants. Constitution: Heat of a reactor core is removed by disposing a spontaneous recycling cooling device for cooling moderators in a moderator tank, without using additional power driven equipments. That is, a spontaneous recycling cooling device for cooling the moderators in the moderator tank is disposed. Further, the gap between the inner wall of a pressure tube guide pipe disposed through the vertical direction of a moderator tank and the outer wall of a pressure tube inserted through the guide pipe is made smaller than the rupture distortion caused by the thermal expansion upon overheating of the pressure tube and greater than the minimum gap required for heat shiels between the pressure tube and the pressure tube guide pipe during usual operation. In this way, even if such an accident as can not using a coolant cooling device comprising power driven equipment should occur in the pressure tube type reactor, the rise in the temperature of the reactor core can be retarded to obtain a margin with time. (Kamimura, M.)

  10. Insertion Modeling and Its Applications

    OpenAIRE

    Alexander Letichevsky; Oleksandr Letychevskyi; Vladimir Peschanenko

    2016-01-01

    The paper relates to the theoretical and practical aspects of insertion modeling. Insertion modeling is a theory of agents and environments interaction where an environment is considered as agent with a special insertion function. The main notions of insertion modeling are presented. Insertion Modeling System is described as a tool for development of different kinds of insertion machines. The research and industrial applications of Insertion Modeling System are presented.

  11. Percutaneous Ureteral stent insertion

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yup; Sung, Dong Wook; Choi, Woo Suk; Lee, Dong Ho; Ko, Young Tae; Lee, Sun Wha; Lim, Jae Hoon [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1990-10-15

    Percutaneous ureteral stent insertion is a treatment of permanent or temporary urinary diversion to maintain continuity and function of the obstructed and injured ureter. We performed 31 cases of percutaneous double pig tall ureteral stent insertion in 21 patients, included 13 patients with malignant ureteral obstruction and eight patients with injured ureter as well as benign inflammatory stricture. Satisfactory resulted was obtained in all patients but one, who need percutaneous nephrostomy on week later for urinary diversion. No significant complication was encountered. The authors concluded that percutaneous ureteral stent insertion, an interventional procedure alternative to urologic retrograde method, is an effective method for urinary diversion.

  12. Tube-in-shell heat exchangers

    International Nuclear Information System (INIS)

    Richardson, J.

    1976-01-01

    Tube-in-shell heat exchangers normally comprise a bundle of parallel tubes within a shell container, with a fluid arranged to flow through the tubes in heat exchange with a second fluid flowing through the shell. The tubes are usually end supported by the tube plates that separate the two fluids, and in use the tube attachments to the tube plates and the tube plates can be subject to severe stress by thermal shock and frequent inspection and servicing are required. Where the heat exchangers are immersed in a coolant such as liquid Na such inspection is difficult. In the arrangement described a longitudinally extending central tube is provided incorporating axially spaced cylindrical tube plates to which the opposite ends of the tubes are attached. Within this tube there is a tubular baffle that slidably seals against the wall of the tube between the cylindrical tube plates to define two co-axial flow ducts. These ducts are interconnected at the closed end of the tube by the heat exchange tubes and the baffle comprises inner and outer spaced walls with the interspace containing Ar. The baffle is easily removable and can be withdrawn to enable insertion of equipment for inspecting the wall of the tube and tube attachments and to facilitate plugging of defective tubes. Cylindrical tube plates are believed to be superior for carrying pressure loads and resisting the effects of thermal shock. Some protection against thermal shock can be effected by arranging that the secondary heat exchange fluid is on the tube side, and by providing a thermal baffle to prevent direct impingement of hot primary fluid on to the cylindrical tube plates. The inner wall of the tubular baffle may have flexible expansible region. Some nuclear reactor constructions incorporating such an arrangement are described, including liquid metal reactors. (U.K.)

  13. Surgical Results of Trabeculectomy and Ahmed Valve Implantation Following a Previous Failed Trabeculectomy in Primary Congenital Glaucoma Patients

    OpenAIRE

    Lee, Naeun; Ma, Kyoung Tak; Bae, Hyoung Won; Hong, Samin; Seong, Gong Je; Hong, Young Jae; Kim, Chan Yun

    2015-01-01

    Purpose To compare the surgical results of trabeculectomy and Ahmed glaucoma valve implantation after a previous failed trabeculectomy. Methods A retrospective comparative case series review was performed on 31 eye surgeries in 20 patients with primary congenital glaucoma who underwent trabeculectomy or Ahmed glaucoma valve implantation after a previous failed trabeculectomy with mitomycin C. Results The preoperative mean intraocular pressure was 25.5 mmHg in the trabeculectomy group and 26.9...

  14. [Results of fistulizing and Ahmed valve surgery for treatment of refractory glaucoma].

    Science.gov (United States)

    Bikbov, M M; Babushkin, A E; Chaĭka, O V; Orenburkina, O I; Matiukhina, E N

    2014-01-01

    Surgical results of 76 patients (76 eyes) aged 25-79 years with secondary refractory glaucoma were analyzed. The best hypotensive effect and visual functions integrity were achieved with Ahmed valve implantation (86.7% and 83.3% of cases respectively); after conventional fistulizing surgery the hypotensive effect was observed in 45.5%, noncompromised vision--in 54.5% of cases. Tunnel trabeculectomy with iridocycloretraction led to normalization of intraocular pressure and stabilization of visual functions in 81.3% and 68.8% of cases respectively and thus can be considered as an alternative to fistulizing surgery in patients with secondary refractory glaucoma. Uveal glaucoma is a relative contraindication to Ahmed valve implantation, while neovascular glaucoma is that to tunnel trabeculectomy with iridocycloretraction.

  15. Patch Grafting Using an Ologen Collagen Matrix to Manage Tubal Exposure in Glaucoma Tube Shunt Surgery

    Directory of Open Access Journals (Sweden)

    Masaki Tanito

    2018-01-01

    Full Text Available Purpose: To report the results using an ologen Collagen Matrix as a patch graft in eyes with tubal exposure after tube shunt surgery. Case Reports: Case 1 was an 82-year-old man with tubal exposure in his right eye 26 months after receiving a Baerveldt glaucoma implant. The tube was covered by surrounding conjunctival tissue combined with subconjunctival placement of an ologen Collagen Matrix as a patch graft. Two years after implantation, the tube was not exposed. Anterior-segment optical coherence tomography (AS-OCT showed dense conjunctival tissue over the tube. Case 2 was an 82-year-old man with peripheral keratitis, anterior scleritis, and secondary glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve and cataract surgery. Intraoperatively, scleritis-related scleral thinning prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Seventeen months after implantation, the tube was not exposed. Case 3 was a 52-year-old man with diabetic maculopathy and steroid-induced glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve. Intraoperatively, a flap defect prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Three weeks postoperatively, AS-OCT showed thick subconjunctival tissue over the tube. Three months after implantation, the tube was not exposed. Conclusions: The ologen Collagen Matrix can be used successfully as a patch graft to prevent and treat tubal exposure after tube shunt surgery.

  16. Ahmed Hilmi Pasha (1839-1905): A remarkable Ottoman physician and medical translator.

    Science.gov (United States)

    Tekiner, Halil

    2016-09-15

    Besides being a founding member of the Ottoman Medical Society (est. 1867) and general director of the Imperial Military and Civil medical schools in Istanbul, Dr Ahmed Hilmi Pasha offered a pathology course for the first time in the Ottoman Empire. He also translated various medical textbooks from French, and he paved the way for using Turkish in Ottoman medical education. © The Author(s) 2016.

  17. Efficacy of intravitreal ranibizumab combined with Ahmed glaucoma valve implantation for the treatment of neovascular glaucoma.

    Science.gov (United States)

    Tang, Min; Fu, Yang; Wang, Ying; Zheng, Zhi; Fan, Ying; Sun, Xiaodong; Xu, Xun

    2016-01-09

    Neovascular glaucoma is a refractive glaucoma. Recently, anti-VEGF factors have been used alone or in combination for the treatment of neovascular glaucoma. However, the medium- and long-term efficacy of such drugs remains to be evaluated. This study was to determine the efficacy of intravitreal ranibizumab combined with Ahmed glaucoma valve implantation for the treatment of neovascular glaucoma. In this prospective non-randomized study, 43 neovascular glaucoma patients (43 eyes) were assigned to receive either 0.5 mg intravitreal ranibizumab for three to 14 days before Ahmed glaucoma valve implantation (injection group, n = 21) or Ahmed glaucoma valve implantation alone (control group, n = 22). The patients were followed up for six to 12 months. Differences in surgical success rate, intraocular pressure, best corrected visual acuity, anti-glaucoma medications and postoperative complications were compared between the two groups. Surgical success was defined as IOP > = 6 mm Hg and glaucoma medications, and without severe complications or reoperation. Of the 43 patients, 40 completed the 6-month follow-up and 37 completed the 1-year follow-up. Success rate was 73.7% vs. 71.4% at six months and 72.2% vs. 68.4% at 12 months in the injection group and the control group respectively. No significant difference was noted between the two groups (six months: P = 0.87, 12 months: P = 1.00). There were no significant differences in the two groups with respect to intraocular pressure, best corrected visual acuity, anti-glaucoma medications or postoperative complications at six months or 12 months. Single intravitreal ranibizumab (0.5 mg) before surgery has no significant effect on the medium- or long-term outcomes of neovascular glaucoma treated with Ahmed glaucoma valve implantation. Chinese Clinical Trial Registry ( ChiCTR-OOC-14005709, Trial registration date: 2014-12-01).

  18. Bilateral Ocular Decompression Retinopathy after Ahmed Valve Implantation for Uveitic Glaucoma

    Directory of Open Access Journals (Sweden)

    Javier Flores-Preciado

    2016-11-01

    Full Text Available Case Report: We report the case of a 29-year-old man who underwent Ahmed valve implantation in both eyes as treatment for uveitic glaucoma, subsequently presenting with bilateral ocular decompression retinopathy in the postoperative period. Discussion: Ocular decompression retinopathy is a rare complication of filtering surgery in patients with glaucoma; however, the course is benign in most cases, with spontaneous resolution of bleedings and improvement of visual acuity.

  19. Zakajev: Tšetšeenia on Euroopa, mitte Vene siseasi / Ahmed Zakajev ; interv. Kadri Liik

    Index Scriptorium Estoniae

    Zakajev, Ahmed

    2003-01-01

    Tšetšeenia presidendi Aslan Mashadovi esindaja Ahmed Zakajev vastab küsimustele, mis puudutavad tema kohtuasja, Vene-Tšetšeenia konflikti, tshetsheenide tungimist Dagestani 1999. aastal. Tema hinnangul saab püsiva rahu tuua vaid Tšetšeenia kuulutamine rahvusvaheliseks protektoraadiks. Vt. samas: Analüütik: aitaks rahvusvaheline sekkumine. Tšetšeenia sõdade kronoloogia

  20. Initial clinical experience with Ahmed Valve implantation in refractory pediatric glaucoma

    OpenAIRE

    Novak-Lauš, Katia; Škunca Herman, Jelena; Šimić Prskalo, Marija; Jurišić, Darija; Mandić, Zdravko

    2016-01-01

    The purpose is to report on the safety and efficacy of Ahmed Glaucoma Valve (AGV, New World Medical, Inc., Rancho Cucamonga, CA, USA) implantation for the management of refractory pediatric glaucoma observed during one-year follow up period. A retrospective chart review was conducted on 10 eyes, all younger than 11 years, with pediatric glaucoma that underwent AGV implantation for medicamentously uncontrolled intraocular pressure (IOP) between 2010 and 2014. Outcome measures were control of I...

  1. Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure

    OpenAIRE

    Huang, Jingjing; Lin, Jialiu; Wu, Ziqiang; Xu, Hongzhi; Zuo, Chengguo; Ge, Jian

    2015-01-01

    Jingjing Huang,1 Jialiu Lin,1 Ziqiang Wu,2 Hongzhi Xu,3 Chengguo Zuo,1 Jian Ge1 1State Key Laboratory of Ophthalmology, Department of Glaucoma, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Center for Advanced Eye Care, Carson City, NV, USA; 3Institute of Child Health Policy, University of Florida, Gainesville, FL, USA Purpose: The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve...

  2. Early postoperative endophthalmitis after pars plana Ahmed valve placement with persistent extraocular infection.

    Science.gov (United States)

    Park, Susanna S; Rabowsky, Jeffrey

    2007-01-01

    This article presents a case of early postoperative endophthalmitis that occurred after vitrectomy and Ahmed Glaucoma Valve (New World Medical, Inc., Rancho Cucamonga, CA) placement and was treated with intravitreal antibiotics. Intravenous vancomycin was started after aqueous culture grew methicillin-resistant Staphylococcus aureus. The endophthalmitis improved, but new purulent discharge around the peritomy was noted 10 days after presentation, requiring removal of the valve.

  3. Hypertensive phase and early complications after Ahmed glaucoma valve implantation with intraoperative subtenon triamcinolone acetonide

    OpenAIRE

    Turalba, Angela; Pasquale,Louis

    2014-01-01

    Angela V Turalba,1,2 Louis R Pasquale1,2 1Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA; 2Department of Ophthalmology, Harvard Medical School, Boston, MA, USA Objective: To evaluate intraoperative subtenon triamcinolone acetonide (TA) as an adjunct to Ahmed glaucoma valve (AGV) implantation. Design: Retrospective comparative case series. Participants: Forty-two consecutive cases of uncontrolled glaucoma undergoing AGV implantation: 19 eyes receivi...

  4. The Ahmed Glaucoma Valve in Refractory Glaucoma: Experiences in Southwest Ethiopia.

    Science.gov (United States)

    Gessesse, Girum W

    2015-07-01

    The management of refractory glaucoma is a challenging task for any glaucoma surgeon. This study is aimed to evaluate the efficacy of Ahmed Glaucoma Valve implantation in refractory glaucomas in South-West Ethiopia. A retrospective review was conducted on the charts of consecutive patients treated with Ahmed glaucoma valve implantation at Jimma University Specialized Hospital between August 2012 and August 2014. Success was defined as Intraocular Pressure (IOP) less than 22 mm Hg and greater than 5mm Hg at 6 months, with at least 30% reduction from baseline, without medical therapy (complete success) or either with or without medication (qualified successes). A total of 12 eyes of 11 patients were included. The mean age of patients was 40.7 (SD= 19.0) years; 63.6% of them were males. The main types of glaucoma were pseudoexfoliative (3 eyes), uveitic (2 eyes), chronic angle closure (2 eyes) and Juvenile Open Angle (JOAG) (2 eyes). The mean IOP was reduced from preoperative level (32.75±7.14 mmHg) to (15.75 ±4.35 mmHg) at six postoperative months, (PAhmed glaucoma valve implant appears to be effective and relatively safe for treating complicated glaucomas with success rate comparable with those reported from other studies. Ahmed glaucoma valve, refractory glaucoma, complications, Ethiopia.

  5. Pars plana Ahmed valve and vitrectomy in patients with glaucoma associated with posterior segment disease.

    Science.gov (United States)

    Wallsh, Josh O; Gallemore, Ron P; Taban, Mehran; Hu, Charles; Sharareh, Behnam

    2013-01-01

    To assess the safety and efficacy of a modified technique for pars plana placement of the Ahmed valve in combination with pars plana vitrectomy in the treatment of glaucoma associated with posterior segment disease. Thirty-nine eyes with glaucoma associated with posterior segment disease underwent pars plana vitrectomy combined with Ahmed valve placement. All valves were placed in the pars plana using a modified technique, without the pars plana clip, and using a scleral patch graft. The 24 eyes diagnosed with neovascular glaucoma had an improvement in intraocular pressure from 37.6 mmHg to 13.8 mmHg and best-corrected visual acuity from 2.13 logarithm of minimum angle of resolution to 1.40 logarithm of minimum angle of resolution. Fifteen eyes diagnosed with steroid-induced glaucoma had an improvement in intraocular pressure from 27.9 mmHg to 14.1 mmHg and best-corrected visual acuity from 1.38 logarithm of minimum angle of resolution to 1.13 logarithm of minimum angle of resolution. Complications included four cases of cystic bleb formation and one case of choroidal detachment and explantation for hypotony. Ahmed valve placement through the pars plana during vitrectomy is an effective option for managing complex cases of glaucoma without the use of the pars plana clip.

  6. Clinical outcomes of trabeculectomy vs. Ahmed glaucoma valve implantation in patients with penetrating keratoplasty : (Trabeculectomy vs. Ahmed galucoma valve in patients with penetrating keratoplasty).

    Science.gov (United States)

    Akdemir, Mehmet Orcun; Acar, Banu Torun; Kokturk, Furuzan; Acar, Suphi

    2016-08-01

    The aim of this study was to compare the visual outcomes, intraocular pressure (IOP), and endothelial cell loss caused by trabeculectomy (TRAB) and Ahmed glaucoma valve (AGV) implantation in patients who had previously undergone penetrating keratoplasty (PKP). The data from all patients who underwent surgical treatment of glaucoma after PKP were reviewed at the Cornea Department of Haydarpasa Numune Education and Research Hospital. Eighteen patients who had undergone surgical treatment of glaucoma after PKP were included in this retrospective study. Time between PKP and glaucoma surgeries, visual acuity results, IOP results, endothelial cell counts (ECC) before the surgery, at 1st, 6th, and 12th month of surgery were recorded. Differences between two groups were evaluated. Mean loss of ECC was 315 cells/mm(2) in the AGV group and 197 cells/mm(2) in TRAB group at 12th month of glaucoma surgery. The difference between endothelial cell loss at 12th month of surgery was statistically significant and higher in AGV group (p glaucoma. Ahmed glaucoma valve had a significantly better IOP lowering but higher endothelial cell loss effect.

  7. Long-term Outcomes of Ahmed Glaucoma Valve Implantation in Refractory Glaucoma at Farabi Eye Hospital, Tehran, Iran.

    Science.gov (United States)

    Zarei, Reza; Amini, Heidar; Daneshvar, Ramin; Nabi, Fahimeh Naderi; Moghimi, Sasan; Fakhraee, Ghasem; Eslami, Yadollah; Mohammadi, Masoud; Amini, Nima

    2016-01-01

    To describe long-term outcomes and complications of Ahmed glaucoma valve (AGV) implantation in subjects with refractory glaucoma at Farabi Eye Hospital, Tehran, Iran. This retrospective cohort study evaluated patient records of all subjects with refractory glaucoma who had undergone AGV implantation up to January 2013. The main outcome measure was the surgical success rate. Complete success was defined as intraocular pressure (IOP) glaucoma medications or additional surgery. Qualified success was IOP glaucoma medications. In all cases, loss of vision (no light perception) was considered an independent indicator of failure. Data were also collected on intraoperative and postoperative complications. Twenty-eight eyes were included in the study. With a mean follow-up of 48.2 ± 31.7 months (median: 40.50 months; range: 3-124 months), the IOP decreased from a mean preoperative value of 30.8 ± 5.6 mmHg to 20.0 ± 6.4 mmHg at last visit. The number of medications decreased from 3.7 ± 0.4 preoperatively to 2.5 ± 1.1 postoperatively. Cumulative qualified success was achieved in 69% of eyes. Mean time to failure according to qualified success criteria was 92.3 ± 9.4 months. Postoperative complications were recorded in 16 (57.1%) eyes. The most common complication was focal endothelial corneal decompensation at the site of tube-cornea touch. AGV implantation with adjunctive topical anti-glaucoma drops controlled IOP in approximately 70% of eyes with refractory glaucoma with a median of 40.5 months of follow-up. However, complication rates were higher.

  8. ALS insertion devices

    International Nuclear Information System (INIS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.V.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.

    1990-11-01

    The Advanced Light Source (ALS), the first US third generation synchrotron radiation source, is currently under construction at the Lawrence Berkeley Laboratory. The low-emittance, 1.5 GeV electron storage ring and the insertion devices are specifically designed to produce high brightness beams in the UV to soft X-Ray range. The planned initial complement of insertion devices includes four 4.6 m long undulators, with period lengths of 3.9 cm, 5.0 cm (2) and 8.0 cm, and a 2.9 m long wiggler of 16 cm period length. Undulator design is well advanced and fabrication has begun on the 5.0 cm and 8.0 cm period length undulators. This paper discusses ALS insertion device requirements; general design philosophy; and design of the magnetic structure, support structure/drive systems, control system and vacuum system. 18 refs., 9 figs., 5 tabs

  9. Reactivity insertion accident analysis

    International Nuclear Information System (INIS)

    Moreira, J.M.L.; Nakata, H.; Yorihaz, H.

    1990-04-01

    The correct prediction of postulated accidents is the fundamental requirement for the reactor licensing procedures. Accident sequences and severity of their consequences depend upon the analysis which rely on analytical tools which must be validated against known experimental results. Present work presents a systematic approach to analyse and estimate the reactivity insertion accident sequences. The methodology is based on the CINETHICA code which solves the point-kinetics/thermohydraulic coupled equations with weighted temperature feedback. Comparison against SPERT experimental results shows good agreement for the step insertion accidents. (author) [pt

  10. ISABELLE insertion quadrupoles

    International Nuclear Information System (INIS)

    Kaugerts, J.; Polk, I.; Sampson, W.; Dahl, P.F.

    1979-01-01

    Beam focussing and control at the beam intersection regions of ISABELLE is accomplished by a number of superconducting insertion quadrupoles. These magnets differ from the standard ISABELLE quadrupoles in various ways. In particular, the requirements of limited space near the intersections and aperture for beam extraction impose constraints on their configuration. To achieve optimum beam focussing and provide tuning flexibility calls for stronger quadrupole trim windings than those in the standard quadrupoles. The magnetic and mechanical design of the insertion quadrupoles and their associated correction and steering windings to accomplish the above tasks is presented

  11. Disc-Donut-Tube wear test report, Phase I

    International Nuclear Information System (INIS)

    Kowal, K.; Knaus, S.E.

    1976-06-01

    The report describes a test program which simulated the wear-inducing conditions in the AI Prototype CRBR Steam Generator. This was accomplished by simulating the wear inducing loading and motion of a steam tube against ''disc-donut'' tube spacer plates. It was found that 2- 1 / 4 Cr-1 Mo tubes, wearing against 2- 1 / 4 Cr-l Mo tube spacer plates, seized and galled as deep as .017 inches. Inconel 718 tube spacer plates uniformly wore the tubes as deep as .012 in. Aluminum bronze inserts wore as deep as .003 inches into the tube

  12. Method of inserting fuel rod

    International Nuclear Information System (INIS)

    Kamimoto, Shuji; Imoo, Makoto; Tsuchida, Kenji.

    1991-01-01

    The present invention concerns a method of inserting a fuel rod upon automatic assembling, automatic dismantling and reassembling of a fuel assembly in a light water moderated reactor, as well as a device and components used therefor. That is, a fuel rod is inserted reliably to an aimed point of insertion by surrounding the periphery of the fuel rod to be inserted with guide rods, and thereby suppressing the movement of the fuel rod during insertion. Alternatively, a fuel rod is inserted reliably to a point of insertion by inserting guide rods at the periphery of the point of insertion for the fuel rod to be inserted thereby surrounding the point of insertion with the guide rods or fuel rods. By utilizing fuel rods already present in the fuel assembly as the guide rods described above, the fuel rod can be inserted reliably to the point of insertion with no additional devices. Dummy fuel rods are previously inserted in a fuel assembly which are then utilized as the above-mentioned guide rods to accurately insert the fuel rod to the point of insertion. (I.S.)

  13. Insertion in Persian

    Science.gov (United States)

    Kambuziya, Aliyeh Kord-e Zafaranlu; Dehghan, Masoud

    2011-01-01

    This paper investigates epenthesis process in Persian to catch some results in relating to vowel and consonant insertion in Persian lexicon. This survey has a close relationship to the description of epenthetic consonants and the conditions in which these consonants are used. Since no word in Persian may begin with a vowel, so that hiatus can't be…

  14. The Composite Insertion Electrode

    DEFF Research Database (Denmark)

    Atlung, Sven; Zachau-Christiansen, Birgit; West, Keld

    1984-01-01

    The specific energy obtainable by discharge of porous insertion electrodes is limited by electrolyte depletion in thepores. This can be overcome using a solid ion conductor as electrolyte. The term "composite" is used to distinguishthese electrodes from porous electrodes with liquid electrolyte...

  15. Horizontal beam tubes in FRM-II

    International Nuclear Information System (INIS)

    Coors, D.; Vanvor, D.

    2001-01-01

    The new research reactor in Garching FRM-II is equipped with 10 leak tight horizontal beam tubes (BT1 - BT10), each of them consisting of a beam tube structure taking an insert with neutron channels. The design of all beam tube structures is similar whereas the inserts are adapted to the special requirements of the using of each beam tube. Inside the reflector tank the beam tube structures are shaped by the inner cones which are made of Al-alloy with circular and rectangular cross sections. They are located in the region of maximum neutron flux (exception BT10), they are directly connected to the flanges of the reflector tank, their lengths are about 1.5 m (exception BT10) and their axes are directed tagentially to the core centre thus contributing to a low γ-noise at the experiments. (orig.)

  16. Tests of compressed geometry NEC acceleration tubes

    International Nuclear Information System (INIS)

    Raatz, J.E.; Rathmell, R.D.; Stelson, P.H.; Ziegler, N.F.

    1985-01-01

    Tests have been performed in the 3 MV Pelletron test machine at NEC on a compressed geometry tube which increases the insulating length of the tube by eliminating the heated electrode assemblies (approx.2.5 cm thick) at the end of each tube section. Some insert electrodes are changed to provide some trapping of secondary ions. The geometry tested provided an 18% increase in live ceramic in the tube. The compressed geometry tube allowed a terminal voltage of 3.55 MV on the 3 MV column at normal gradients of 30.3 kv/tube gap. The tube was also conditioned to more than 4 MV and remained stable in voltage with few sparks and with low x-ray levels for days at about 4 MV. This same performance could be achieved with or without arc discharge cleaning. 4 refs., 4 figs

  17. Fuel insert shuffler

    International Nuclear Information System (INIS)

    Naser, J.; Colley, R.; Gaiser, J.; Brookmire, T.; Engle, S.

    1987-01-01

    The potential for the use of expert systems in the nuclear power industry is widely recognized. The benefits of such systems include consistency of reasoning during off-normal situations when humans are under great stress, the reduction of time required to perform certain functions and the retention of human expertise in performing specialized functions. As the potential benefits are more and more demonstrated and realized, the development of expert systems becomes a necessary part of the nuclear power industry. The development of the fuel insert shuffle expert system is used as a case study. In fact, it shows that the potential benefits are realizable. Currently, the development of the insert shuffle plan requires three to four man-weeks of effort. Further modifications to this plan are sometimes required dur to either changes in the desired core load pattern or damaged fuel assemblies or inserts. These changes generally require two to four man-days of effort and could be stressful if they are critical path items on the outage schedule

  18. Tube shunt complications and their prevention.

    Science.gov (United States)

    Sarkisian, Steven R

    2009-03-01

    Glaucoma drainage devices (GDDs) have been generally accepted as a treatment of refractory glaucoma. GDDs have their own unique set of complications that are important to evaluate to prevent them. Tube shunts are typically used in eyes with refractory glaucoma. There is increased interest in studying the efficacy of GDDs. Most of the attention has been focused on comparing trabeculectomy with the Baerveldt implant (Advanced Medical Optics, Inc., Santa Anna, California, USA). The other leading implant is the Ahmed Glaucoma Valve. There are several retrospective studies comparing these two devices and a prospective study is ongoing. There is great interest in the complication rate of tube shunts and these have been published both retrospectively and prospectively. Complications such as hypotony, diplopia, strabismus, proptosis, tube erosion, failure, corneal decompensation, endophthalmitis, and visual loss are all important and some have recently been reviewed in the literature. Moreover, the use of glaucoma drainage implants in the pediatric population has been evaluated. Glaucoma drainage implants have been a powerful tool in our surgical fight to prevent blindness; however, they are not without complications or controversy.

  19. Short- to long-term results of Ahmed glaucoma valve in the management of elevated intraocular pressure in patients with pediatric uveitis.

    Science.gov (United States)

    Eksioglu, Umit; Yakin, Mehmet; Sungur, Gulten; Satana, Banu; Demirok, Gulizar; Balta, Ozgur; Ornek, Firdevs

    2017-06-01

    The aim of this study was to evaluate the long-term outcome of Ahmed glaucoma valve (AGV) implant for elevated intraocular pressure (IOP) in pediatric patients with uveitis. This was a retrospective chart review. The study included 16 eyes (11 children) with uveitis. Success was defined as having IOP between 6 and 21 mm Hg with (qualified success) or without (complete success) antiglaucoma medications and without the need for further glaucoma or tube extraction surgery. Mean age of patients at the time of AGV implantation was 14.19 ± 3.25 years. AGV implantation was the first glaucoma surgical procedure in 12 eyes (75%). Average postoperative follow-up period was 64.46 ± 33.56 months. Mean preoperative IOP was 33.50 ± 7.30 mm Hg versus 12.69 ± 3.20 mm Hg at the last follow-up visit (p < 0.001). Three eyes (18.7%) were determined as cases of "failure" because of tube removal in 2 eyes and a second AGV implantation in 1 eye. The cumulative probability of complete success was 68.8% at 6 months, 56.3% at 12 months, 49.2% at 36 months, 42.2% at 48 months, and 35.2% at 84 months, and the cumulative probability of eyes without complication was 75.0% at 6 months, 66.7% at 24 months, 58.3% at 36 months, 48.6% at 48 months and 24.3% at 108 months based on Kaplan-Meier survival analysis. Although AGV implant is an effective choice in the management of elevated IOP in pediatric uveitis, antiglaucoma medications are frequently needed for control of IOP. Tube exposure is an important complication in the long term. Differential diagnosis between relapse of uveitis and endophthalmitis is important in patients who received AGV implantation. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  20. Use of a Nasal Speculum for Chest-Drain Insertion: A Simple Technique

    OpenAIRE

    Saxena, Pankaj; Konstantinov, Igor E.; Newman, Mark A.J.

    2006-01-01

    Tube thoracostomy is a very commonly performed procedure in cardiothoracic surgery. Insertion of a chest drain requires expertise to minimize complications. We describe a simple technique of using a nasal speculum to perform this procedure.

  1. PENERAPAN SYARI’AH DI NEGARA MODERN (Analisis Ijtihad Pemikiran Abdullahi Ahmed An-Na’im

    Directory of Open Access Journals (Sweden)

    Ahmad Bahrur Rozi

    2016-02-01

    Full Text Available Islam is a holistic religion. It means that Islam is a religion which does not only focus on the vertical relation between humans and God but also contains rules of horizontal relation between man and man. Laws with social characteristic lead to the existence of a power as the doer, such as the application of all the punishments and public rewards (al-hudûd wa al-'uqûbât. This article analyzes the thought of Abdullahi Ahmed An--Na’im about syari’ah reformation which is relevant to the constitutionalism standard, criminal law, international law and modern human right, a vision of “syariat modern” which is suitable with the nation state concept which beyond  the offering of the Nation of fundamentalist syariah and the offering of Modern Islamic Nation. The method used by Abdullahi Ahmed An--Na’im is the renewal method which is said as legalized evolution with hermeneutic as the main tool to reach the purpose and normative implication of the text as al-Qur’an. According to Abdullahi Ahmed An--Na’im, the failure of syari’ah application in modern country caused by the crisis on the traditional syari’ah methodology which became its base. Therefore, new syari’ah formulation is needed to be built on the new base. Naskh concept which is initiated by An-Na’im is for answering this crisis.Copyright (c 2016 by Al-Ihkam. All right reservedDOI: 10.19105/al-ihkam.v10i2.734

  2. Ahmed glaucoma valve implantation for refractory glaucoma after sequential failed trabeculectomy

    Directory of Open Access Journals (Sweden)

    Zhi-Qin Wu

    2016-07-01

    Full Text Available AIM: To evaluate the safety and efficacy of Ahmed glaucoma valve implantation for refractory glaucoma after sequential failed trabeculectomy. METHODS: Thirty-six patients(36 eyeswith prior failed sequential trabeculectomy who underwent Ahmed glaucoma valve implantation were included. The intraocular pressure(IOP, best corrected visual acuity(BCVAand complications were ovserved and all the patients were followed up at least for 12mo. RESULTS: Mean preoperative IOP was 35.20±7.28mmHg and reduced to 10.15±3.34, 11.23±3.56, 15.63±5.72, 17.17±5.47, 17.73±6.23,19.76±5.43mmHg at 1, 2wk, 1, 3, 6 and 12mo after surgery, which was significant different from the preoperative level(t=12.643, 11.837, 10.324, 8.839, 8.462, 8.046, all PZ=-0.420, P>0.05. At 12mo after operation, the complete success rate reached 78% and the conditional success rate reached 92%. There were 5 eyes complicated with shallow anterior chamber, 3 eye complicated with anterior chamber hemorrhage, which all recovered after additional treatments. Late complications included valve exposure and encapsulated cystic blebs around the plate. Severe corneal endothelium loss occurred in 1 patient. CONCLUSION: Ahmed glaucoma valve implantation is effective in reducing IOP at 1-year follow-up in refractory glaucoma patients with prior sequential failed trabeculectomy, but we should fully understand and attach great importance to all kinds of complications that may occur.

  3. [Lung abscess and necrotizing pneumonia: chest tube insertion or surgery?].

    Science.gov (United States)

    Pagès, P-B; Bernard, A

    2012-04-01

    Lung abscesses and necrotizing pneumonia are rare complications of community-acquired pneumonia since the advent of antibiotics. Their management leans first of all on the antibiotic treatment adapted on the informed germs. However, in 11 to 20% of the cases of lung abscesses, this treatment is insufficient, and drainage, either endoscopic or percutaneous, must be envisaged. In first intention, we shall go to less invasive techniques: endoscopic or percutaneous radio-controlled. In case of failure of these techniques, a percutaneous surgical drainage by minithoracotomy will be performed. In the necrotizing pneumonia, because of the joint obstruction of the bronchus and blood vessels corresponding to a lung segment, the systemic antibiotic treatment will be poor effective. In case of failure of this one we shall propose, a percutaneous surgical drainage, especially if the necrosis limits itself to a single lobe. The surgical treatment will be reserved: in the failures of the strategy of surgical drainage, in the necroses extending in several lobes. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. SVC obstruction and stridor relieved by nasogastric tube insertion.

    Science.gov (United States)

    Molena, Emma J; Krishnamoorthy, Ashwin; Praveen, Coimbatore

    2016-03-01

    Achalasia is an idiopathic motility disorder of the oesophagus of increasing incidence. It is characterized by aperistalsis of the lower oesophagus and failure of relaxation of the lower oesophageal sphincter. Patients classically present with chronic symptoms of dysphagia, chest pain, weight loss and regurgitation, and they commonly suffer pulmonary complications such as recurrent microaspiration of static, retained food contents of the upper oesophagus. However, it has also been described, uncommonly, to present with megaoesophagus and secondary tracheal compression. We present a case of megaoesophagus secondary to achalasia which presented with stridor and signs of acute superior vena caval obstruction. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

  5. Ahmed glaucoma valve in post-penetrating-keratoplasty glaucoma: A critically evaluated prospective clinical study

    Science.gov (United States)

    Panda, Anita; Prakash, Vadivelu Jaya; Dada, Tanuj; Gupta, Anoop Kishore; Khokhar, Sudarshan; Vanathi, Murugesan

    2011-01-01

    Aim: The aim was to evaluate the outcome of Ahmed glaucoma valve (AGV) in post-penetrating-keratoplasty glaucoma (PKPG). Materials and Methods: In this prospective study, 20 eyes of 20 adult patients with post-PKPG with intraocular pressure (IOP) >21 mmHg, on two or more antiglaucoma medications, underwent AG (model FP7) implantation and were followed up for a minimum of 6 months. Absolute success was defined as 5 glaucoma managed by AGV implantation revealed a satisfactory outcome up to 6 months of follow-up. PMID:21586837

  6. A Review of the Ahmed Glaucoma Valve Implant and Comparison with Other Surgical Operations.

    Science.gov (United States)

    Riva, Ivano; Roberti, Gloria; Katsanos, Andreas; Oddone, Francesco; Quaranta, Luciano

    2017-04-01

    The Ahmed glaucoma valve (AGV) is a popular glaucoma drainage implant used for the control of intraocular pressure in patients with glaucoma. While in the past AGV implantation was reserved for glaucoma patients poorly controlled after one or more filtration procedures, mounting evidence has recently encouraged its use as a primary surgery in selected cases. AGV has been demonstrated to be safe and effective in reducing intraocular pressure in patients with primary or secondary refractory glaucoma. Compared to other glaucoma surgeries, AGV implantation has shown favorable efficacy and safety. The aim of this article is to review the results of studies directly comparing AGV with other surgical procedures in patients with glaucoma.

  7. The Ahmed Versus Baerveldt study: design, baseline patient characteristics, and intraoperative complications.

    Science.gov (United States)

    Christakis, Panos G; Tsai, James C; Zurakowski, David; Kalenak, Jeffrey W; Cantor, Louis B; Ahmed, Iqbal I K

    2011-11-01

    To report the design, baseline patient characteristics, and intraoperative complications of the Ahmed Versus Baerveldt (AVB) Study. Multicenter, randomized, clinical trial. Patients were recruited from 7 international clinical sites and treated by 10 surgeons between 2005 and 2009. Inclusion criteria required that patients be at least 18 years of age and have uncontrolled glaucoma refractory to medicinal, laser, and surgical therapy. Eligible patients were randomized to undergo implantation of an Ahmed-FP7 valve (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA) using standardized surgical technique, to be followed for 5 years. The primary outcome measure was failure, defined as intraocular pressure (IOP) out of target range (5-18 mmHg with ≥ 20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, additional glaucoma procedures, or loss of light perception. Secondary outcome measures included IOP, medication use, visual acuity, complications, and interventions. A total of 238 patients were enrolled in the study; 124 received the Ahmed-FP7 valve implant and 114 received the Baerveldt-350 implant. The 2 treatment groups did not differ in any baseline characteristics with the exception of sex. The mean age of the study group was 66 ± 16 years, and 55% were women, with a greater proportion in the Baerveldt group (P=0.01). The mean baseline IOP of the study group was 31.4 ± 10.8 on a mean of 3.1 ± 1.0 glaucoma medications. The median Snellen visual acuity was 20/100, mean number of previous laser therapies was 0.9 ± 1.1, and mean number of previous surgeries was 1.7 ± 1.2. Five (4%) patients in the Ahmed group and 4 (4%) patients in the Baerveldt group experienced significant intraoperative complications. Aqueous drainage devices are being increasingly used for glaucoma refractory to conventional treatment, and the AVB Study compares the 2 most

  8. Evaluation of Ahmed valve in the glaucoma of poor surgical prognosis

    OpenAIRE

    García González, Francisco; Novoa Sánchez, Ester; San Martín Geisse, Raúl

    2001-01-01

    Se intervinieron 8 pacientes con glaucoma de mal pronóstico quirúrgico a los que se les implantaron una válvula de Ahmed con la técnica quirúrgica convencional. Se logró controlar la presión intraocular (PIO). Las complicaciones fueron: hipotonía (75 %), desprendimiento coroideo (37,5 %), hifema (25,0 %), contacto tubo iridiano (25, 0 %), hipotalamia (12,5 %) y congestión en el área del implante (12,5 %). No hubo complicaciones intraoperatorias. Se obtuvieron resultados satisfactorios a media...

  9. Feeding Tubes

    Science.gov (United States)

    ... feeding therapies have been exhausted. Please review product brand and method of placement carefully with your physician ... Total Parenteral Nutrition. Resources: Oley Foundation Feeding Tube Awareness Foundation Children’s Medical Nutrition Alliance APFED’s Educational Webinar ...

  10. Fuel assembly insertion system

    International Nuclear Information System (INIS)

    Barkhurst, D.J.

    1987-01-01

    This patent describes a nuclear reactor facility having fuel bundles: a system for the insertion of a fuel bundle into a position where vertically arranged fuel bundles surround and are adjacent the system comprising, in combination, separate and individual centering devices secured to and disposed on top of each fuel bundle adjacent the position. Each such centering device has a generally box-like cap configuration on the upper end of each fuel bundle and includes: a top wall; first and second side walls, each secured along and upper edge to the top wall; a rear plate attached along opposite vertical edges to the first and second side walls; a front inclined wall joined along an upper edge to the top to the wall and attached along opposite vertical edges first and second side walls; pad means secured to the lower edge of the first and second side walls, the front inclined wall and the rear plate for mounting each centering device on top of an associated fuel bundle; pin means carried by at least two of the pad means engageable with an associated aperature for locating and laterally fixing each centering device on top of its respective fuel bundle. Each front inclined wall of each of the centering devices is orientated on top of its respective fuel bundle to slope upwardly and away from the position where upon downward insertion of a fuel bundle any contact between the lower end of the fuel bundle inserted with a front inclined wall of a centering device will laterally deflect the fuel bundle. Each centering device further includes a central socket means secured to the top wall, and an elongated handling pole pivotally attached to the socket

  11. Apparatus for inspecting and repairing a pressurized-water reactor's steam generator heat exchanger tubes

    International Nuclear Information System (INIS)

    Mueller, O.; Roettger, H.; Kasti, H.; Hagen, H.G.

    1976-01-01

    Described is an apparatus provided for use with a pressurized-water reactor' steam generator having a manifold chamber enclosing the bottom side of a horizontal tube sheet having holes therethrough in which are mounted the tubes of a heat exchanger tube bundle. The manifold chamber has a manhole giving access to the tube's bottom side to permit internal inspection or repair of the tubes by registration of an end of a flexible guide conduit with the tube sheet holes and through which a flexible carrier can be guided for insertion via these holes in the tube sheet and through the tubes extending from the tube sheet's other side

  12. Sleeve type repair of degraded nuclear steam generator tubes

    International Nuclear Information System (INIS)

    Ayres, P.S.; Stark, L.E.; Feldstein, J.G.; Fu, T.

    1986-01-01

    A sealable sleeve is described for insertion into the repair of a degraded tube which consists of: a hollow core inner member of the same material as the degraded tube; a thinner outer member of substantially pure nickel and resistant to corrosive attack, the outer member being metallurgically bonded with the inner member; an expanded portion of the sleeve at one end for positioning in the tube within a tube sheet; a multiplicity of grooves formed in and adjacent to the other end of the sleeve which extends into the free-standing portion of the tube beyond the tube sheet, and a noble metal braze material contained in the grooves

  13. Data Insertion in Bitcoin's Blockchain

    Directory of Open Access Journals (Sweden)

    Andrew Sward

    2018-04-01

    Full Text Available This paper provides the first comprehensive survey of methods for inserting arbitrary data into Bitcoin’s blockchain. Historical methods of data insertion are described, along with lesser-known techniques that are optimized for efficiency. Insertion methods are compared on the basis of efficiency, cost, convenience of data reconstruction, permanence, and potentially negative impact on the Bitcoin ecosystem.

  14. Steam generator tube extraction

    International Nuclear Information System (INIS)

    Delorme, H.

    1985-05-01

    To enable tube examination on steam generators in service, Framatome has now developed a process for removing sections of steam generator tubes. Tube sections can be removed without being damaged for treating the tube section expanded in the tube sheet

  15. Non-symmetric bi-stable flow around the Ahmed body

    International Nuclear Information System (INIS)

    Meile, W.; Ladinek, T.; Brenn, G.; Reppenhagen, A.; Fuchs, A.

    2016-01-01

    Highlights: • The non-symmetric bi-stable flow around the Ahmed body is investigated experimentally. • Bi-stability, described for symmetric flow by Cadot and co-workers, was found in nonsymmetric flow also. • The flow field randomly switches between two states. • The flow is subject to a spanwise instability identified by Cadot and co-workers for symmetric flow. • Aerodynamic forces fluctuate strongly due to the bi-stability. - Abstract: The flow around the Ahmed body at varying Reynolds numbers under yawing conditions is investigated experimentally. The body geometry belongs to a regime subject to spanwise flow instability identified in symmetric flow by Cadot and co-workers (Grandemange et al., 2013b). Our experiments cover the two slant angles 25° and 35° and Reynolds numbers up to 2.784 × 10"6. Special emphasis lies on the aerodynamics under side wind influence. For the 35° slant angle, forces and moments change significantly with the yawing angle in the range 10° ≤ |β| ≤ 15°. The lift and the pitching moment exhibit strong fluctuations due to bi-stable flow around a critical angle β of ±12.5°, where the pitching moment changes sign. Time series of the forces and moments are studied and explained by PIV measurements in the flow field near the rear of the body.

  16. Combined Phacoemulsification and Ahmed Glaucoma Drainage Implant Surgery for Patients With Refractory Glaucoma and Cataract.

    Science.gov (United States)

    Valenzuela, Felipe; Browne, Andrew; Srur, Miguel; Nieme, Carlos; Zanolli, Mario; López-Solís, Remigio; Traipe, Leonidas

    2016-02-01

    To examine the indications, safety, efficacy, and complications of combined phacoemulsification and Ahmed glaucoma drainage implant surgery. A retrospective case review of 35 eyes (31 patients) subjected to combined phacoemulsification and Ahmed glaucoma drainage implant surgery. Demographic characteristics of the study population, indications for combined surgery, and operative and postoperative complications were recorded. Visual acuity, intraocular pressure (IOP), and number of glaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as IOP ≤ 21 mm Hg without medication, qualified success if IOP ≤ 21 mm Hg with ≥ 1 medications, and failure if IOP>21 mm Hg or ≤ 5 mm Hg on ≥ 2 consecutive visits. Mean follow-up was 29.5 months (range, 6 to 87 mo). The most common indication for combined surgery was a history of prior failed trabeculectomy (60%). Postoperative visual acuity improved in 30 of 35 eyes (85%) (PAhmed glaucoma drainage implant surgery seems to be a safe and effective surgical option, providing good visual rehabilitation and control of IOP for patients with refractory glaucoma and cataract.

  17. Intraocular pressure control after the implantation of a second Ahmed glaucoma valve.

    Science.gov (United States)

    Jiménez-Román, Jesús; Gil-Carrasco, Félix; Costa, Vital Paulino; Schimiti, Rui Barroso; Lerner, Fabián; Santana, Priscila Rezende; Vascocellos, Jose Paulo Cabral; Castillejos-Chévez, Armando; Turati, Mauricio; Fabre-Miranda, Karina

    2016-06-01

    The objective of this study is to evaluate the efficacy and safety of a second Ahmed glaucoma valve (AGV) in eyes with refractory glaucoma that had undergone prior Ahmed device implantation. This multicenter, retrospective study evaluated 58 eyes (58 patients) that underwent a second AGV (model S2-n = 50, model FP7-n = 8) due to uncontrolled IOP under maximal medical therapy. Outcome measures included IOP, visual acuity, number of glaucoma medications, and postoperative complications. Success was defined as IOP glaucoma medications preoperatively at 12 and 30 months were 3.17 ± 0.16 (n = 58), 1.81 ± 0.2 (n = 42), and 1.83 ± 0.35 (n = 18), respectively. The reductions in mean IOP and number of medications were statistically significant at all time intervals (P glaucoma, and is associated with relatively few complications.

  18. [How to do - the chest tube drainage].

    Science.gov (United States)

    Klopp, Michael; Hoffmann, Hans; Dienemann, Hendrik

    2015-03-01

    A chest tube is used to drain the contents of the pleural space to reconstitute the physiologic pressures within the pleural space and to allow the lungs to fully expand. Indications for chest tube placement include pneumothorax, hemothorax, pleural effusion, pleural empyema, and major thoracic surgery. The most appropriate site for chest tube placement is the 4th or 5th intercostal space in the mid- or anterior- axillary line. Attention to technique in placing the chest tube is vital to avoid complications from the procedure. Applying the step-by-step technique presented, placement of a chest tube is a quick and safe procedure. Complications - frequently occurring when the tube is inserted with a steel trocar - include hemothorax, dislocation, lung lacerations, and injury to organs in the thoracic or abdominal cavity." © Georg Thieme Verlag KG Stuttgart · New York.

  19. Changes in corneal endothelial cell density and the cumulative risk of corneal decompensation after Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Kim, Kyoung Nam; Lee, Sung Bok; Lee, Yeon Hee; Lee, Jong Joo; Lim, Hyung Bin; Kim, Chang-Sik

    2016-07-01

    To evaluate changes in the corneal endothelial cell density (ECD) and corneal decompensation following Ahmed glaucoma valve (AGV) implantation. This study was retrospective and observational case series. Patients with refractory glaucoma who underwent AGV implantation and were followed >5 years were consecutively enrolled. We reviewed the medical records, including the results of central corneal specular microscopy. Of the 127 enrolled patients, the annual change in ECD (%) was determined using linear regression for 72 eyes evaluated at least four times using serial specular microscopic examination and compared with 31 control eyes (fellow glaucomatous eyes under medical treatment). The main outcome measures were cumulative risk of corneal decompensation and differences in the ECD loss rates between subjects and controls. The mean follow-up after AGV implantation was 43.1 months. There were no cases of postoperative tube-corneal touch. The cumulative risk of corneal decompensation was 3.3%, 5 years after AGV implantation. There was a more rapid loss of ECD in the 72 subject eyes compared with the 31 controls (-7.0% and -0.1%/year, respectively; p<0.001). However, the rate of loss decreased over time and statistical significance compared with control eyes disappeared after 2 years postoperatively: -10.7% from baseline to 1 year (p<0.01), -7.0% from 1 year to 2 years (p=0.037), -4.2% from 2 years to 3 years (p=0.230) and -2.7% from 3 years to the final follow-up (p=0.111). In case of uncomplicated AGV implantation, the cumulative risk of corneal decompensation was 3.3%, 5 years after the operation. The ECD loss was statistically greater in eyes with AGV than in control eyes without AGV, but the difference was significant only up to 2 years post surgery. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Improved drainage with active chest tube clearance.

    Science.gov (United States)

    Shiose, Akira; Takaseya, Tohru; Fumoto, Hideyuki; Arakawa, Yoko; Horai, Tetsuya; Boyle, Edward M; Gillinov, A Marc; Fukamachi, Kiyotaka

    2010-05-01

    This study was performed to evaluate the efficacy of a novel chest drainage system. This system employs guide wire-based active chest tube clearance to improve drainage and maintain patency. A 32 Fr chest tube was inserted into pleural cavities of five pigs. On the left, a tube was connected to the chest canister, and on the right, the new system was inserted between the chest tube and chest canister. Acute bleeding was mimicked by periodic infusion of blood. The amount of blood drained from each chest cavity was recorded every 15 min for 2 h. After completion of the procedure, all residual blood and clots in each chest cavity were assessed. The new system remained widely patent, and the amount of drainage achieved with this system (670+/-105 ml) was significantly (P=0.01) higher than that with the standard tube (239+/-131 ml). The amount of retained pleural blood and clots with this system (150+/-107 ml) was significantly (P=0.04) lower than that with the standard tube (571+/-248 ml). In conclusion, a novel chest drainage system with active tube clearance significantly improved drainage without tube manipulations. 2010 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.

  1. Ahmed Zakajev: Litvinenko tapeti, sest ta abistas omakasupüüdmatult tšetšeene / Tõnis Erilaid

    Index Scriptorium Estoniae

    Erilaid, Tõnis, 1943-

    2007-01-01

    Vene ajalehes Kommersant ilmus intervjuu endise Itškeeria ministri Ahmed Zakajeviga, kes ei kahtle, et Aleksandr Litvinenko tapmisega on seotud Andrei Lugovoi. Suurbritannia politsei tegutseb täie tõsidusega, et sundida Venemaad Andrei Lugovoid välja andma

  2. Reconciling different legal spheres in theory and practice: pluralism and constitutionalism in the cases of Al Jedda, Ahmed and Nada

    NARCIS (Netherlands)

    Eckes, C.; Hollenberg, S.

    2013-01-01

    A detailed analysis of four judicial responses to extreme pluri-contextual settings, the House of Lords’ and the European Court of Human Rights (ECtHR)’s rulings in Al-Jedda, the UK Supreme Court’s judgment in Ahmed, and the ECtHR’s recent ruling in Nada, demonstrates that all three courts relied on

  3. Late-onset endophthalmitis secondary to exposed glaucoma tube implant in a rare case of paediatric glaucoma.

    Science.gov (United States)

    Ranganath, Akshatha; Hashim, Adnan

    2011-01-01

    Glaucoma drainage implants (GDIs) are used to treat paediatric glaucoma resistant to conventional medical and surgical treatment, achieving good intraocular pressure (IOP) control and long-term success. Late endophthalmitis is a rare complication that may develop following GDI surgery. A 17-year-old male presented with acute endophthalmitis 2 years after Ahmed glaucoma valve implantation with pericardial patch graft for management of refractory glaucoma secondary to congenital ectropion uveae. The glaucoma tube was exposed due to erosion of the overlying conjunctiva with no visible pericardial graft. After control of active infection, he underwent tube revision surgery whereby the exposed tube was retained and repatched with a double-thickness pericardial patch graft. He did well following surgery with good control of IOP and restoration of vision. Conjunctival dehiscence with graft melting over the GDI tube presented a major risk factor for endophthalmitis. Prompt surgical revision of an exposed tube is highly recommended to avoid ocular morbidity.

  4. Late-Onset Endophthalmitis Secondary to Exposed Glaucoma Tube Implant in a Rare Case of Paediatric Glaucoma

    Directory of Open Access Journals (Sweden)

    Akshatha Ranganath

    2011-01-01

    Full Text Available Glaucoma drainage implants (GDIs are used to treat paediatric glaucoma resistant to conventional medical and surgical treatment, achieving good intraocular pressure (IOP control and long-term success. Late endophthalmitis is a rare complication that may develop following GDI surgery. A 17-year-old male presented with acute endophthalmitis 2 years after Ahmed glaucoma valve implantation with pericardial patch graft for management of refractory glaucoma secondary to congenital ectropion uveae. The glaucoma tube was exposed due to erosion of the overlying conjunctiva with no visible pericardial graft. After control of active infection, he underwent tube revision surgery whereby the exposed tube was retained and repatched with a double-thickness pericardial patch graft. He did well following surgery with good control of IOP and restoration of vision. Conjunctival dehiscence with graft melting over the GDI tube presented a major risk factor for endophthalmitis. Prompt surgical revision of an exposed tube is highly recommended to avoid ocular morbidity.

  5. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  6. Impact of same-session trabectome surgery on Ahmed glaucoma valve outcomes.

    Science.gov (United States)

    Esfandiari, Hamed; Shazly, Tarek; Shah, Priyal; Hassanpour, Kiana; Torkian, Pooya; Yaseri, Mehdi; Loewen, Nils A

    2018-03-30

    To evaluate the efficacy and survival rates of same session ab interno trabeculectomy with the trabectome and Ahmed glaucoma valve implant (AT) in comparison to the Ahmed glaucoma valve alone (A). A total of 107 eyes undergoing primary glaucoma surgery were enrolled in this retrospective comparative case series, including 48 eyes which underwent AT and 59 eyes which received A alone. Participants were identified using the procedural terminology codes, and their medical records were reviewed. The primary outcome measure was success defined as IOP > 5 mmHg, ≤ 21 mmHg and ≥ 20% reduction of IOP from baseline at two consecutive visits after 3 months, and no need for glaucoma reoperation. Secondary outcome measures were IOP, the number of glaucoma medications, incidence of a hypertensive phase, and best corrected visual acuity (BCVA). The cumulative probability of success at 1 year was 70% in AT, and 65% in A (p = 0.85). IOP decreased significantly from 26.6 ± 10.1 mmHg at baseline to 14.7 ± 3.3 mmHg at the final follow-up in AT (p = 0.001). The corresponding numbers for A were 27.8 ± 10.2 and 16.7 ± 4.9, respectively (p = 0.001). The final IOP was significantly lower in AT (p = 0.022). The number of medications at baseline was comparable in both groups (2.6 ± 1.2 in AT and 2.5 ± 1.3 in A, p = 0.851). Corresponding number at 1 year visit was 1.2 ± 2 in AT and 2.8 ± 1.8 in A (p = 0.001). The incidence of a hypertensive phase was 18.7% in AT and 35.5% in A (p = 0.05). HP resolved in only 30% of eyes. The criteria for HP resolution were fulfilled in 9 eyes (30%). There was no difference in the rate of resolution of the hypertensive phase between AT and A (33.3 and 28.5%, respectively, p = 0.67). Ahmed glaucoma valve implant with same session trabectome surgery significantly decreased the rate of the hypertensive phase and postoperative IOP as well as the number of glaucoma

  7. Facility target insert shielding assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mocko, Michal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-06

    Main objective of this report is to assess the basic shielding requirements for the vertical target insert and retrieval port. We used the baseline design for the vertical target insert in our calculations. The insert sits in the 12”-diameter cylindrical shaft extending from the service alley in the top floor of the facility all the way down to the target location. The target retrieval mechanism is a long rod with the target assembly attached and running the entire length of the vertical shaft. The insert also houses the helium cooling supply and return lines each with 2” diameter. In the present study we focused on calculating the neutron and photon dose rate fields on top of the target insert/retrieval mechanism in the service alley. Additionally, we studied a few prototypical configurations of the shielding layers in the vertical insert as well as on the top.

  8. Ahmed Zewail

    Indian Academy of Sciences (India)

    USA to start his PhD under the supervision of a renowned professor ... An English translation of the classic paper by Eyring and Polanyi in 1931 on the .... with the scientific planning in Egypt, and he also tried to set up a world class university in.

  9. Ahmed BOUYACOUB

    African Journals Online (AJOL)

    ACER

    investissements réalisés dans notre pays depuis l'indépendance et la croissance .... Autrement dit, l'Algérie a investi presque 4 fois plus que la Tunisie,. 90 % de plus que ...... place et, pour la première fois de son histoire, dans le groupe de.

  10. [Prehospital airway management of laryngeal tubes. Should the laryngeal tube S with gastric drain tube be preferred in emergency medicine?].

    Science.gov (United States)

    Dengler, V; Wilde, P; Byhahn, C; Mack, M G; Schalk, R

    2011-02-01

    Laryngeal tubes (LT) are increasingly being used for emergency airway management. This article reports on two patients in whom out-of-hospital intubation with a single-lumen LT was associated with massive pulmonary aspiration in one patient and gastric overinflation in the other. In both cases peak inspiratory pressures exceeded the LT leak pressure of approximately 35 mbar. This resulted in gastric inflation and decreased pulmonary compliance and increased inspiratory pressure further, thereby creating a vicious circle. It is therefore recommended that laryngeal tube suction (LTS) should be used in all cases of emergency airway management and a gastric drain tube be inserted through the dedicated second lumen. Apart from gastric overinflation, incorrect LT/LTS placement must be detected and immediately corrected, e.g. in cases of difficult or impossible gastric tube placement, permanent drainage of air from the gastric tube, decreasing minute ventilation or an ascending capnography curve.

  11. Insertion device and method for accurate and repeatable target insertion

    Science.gov (United States)

    Gubeli, III, Joseph F.; Shinn, Michelle D.; Bevins, Michael E.; Dillon-Townes, Lawrence; Neil, George R.

    2017-07-04

    The present invention discloses a device and a method for inserting and positioning a target within a free electron laser, particle accelerator, or other such device that generates or utilizes a beam of energy or particles. The system includes a three-point registration mechanism that insures angular and translational accuracy and repeatability of positioning upon multiple insertions within the same structure.

  12. Subinternal limiting membrane hemorrhage post-Ahmed glaucoma valve in vitrectomized eye

    Directory of Open Access Journals (Sweden)

    Bhuvan Chanana

    2018-01-01

    Full Text Available Glaucoma drainage devices are mostly used for refractory glaucoma. Early postoperative complications include flat anterior chamber, choroidal effusion, and suprachoroidal hemorrhage. An 8-year-old male patient with a prior history of vitreous surgery for traumatic vitreous hemorrhage, presented to us with angle recession glaucoma in his right eye. His intraocular pressure (IOP was 44 mmHg despite maximum antiglaucoma medication. Ahmed glaucoma valve (AGV surgery was performed to control his IOP. In the early postoperative period, the patient developed premacular subinternal limiting membrane (ILM hemorrhage, which did not resolve even after 4 weeks. Vitreoretinal intervention involving removal of the thickened ILM and sub-ILM bleed had to be performed. To the best of our knowledge, no case has been reported with sub-ILM bleed post aqueous humor shunts. Here, we report a case of premacular sub-ILM bleed following AGV in vitrectomized eye.

  13. Clinical observation on Ahmed glaucoma valve implantation for teenagers with refractory glaucoma

    Directory of Open Access Journals (Sweden)

    Dong-Dao Song

    2016-06-01

    Full Text Available AIM:To observe the clinical effect of Ahmed glaucoma valve(AGVimplantation for teenagers with refractory glaucoma. METHODS: Twenty-seven patients(27 eyeswith refractory glaucoma were treated with AGV implantation in our hospital from October 2012 to October 2014. The patients were followed up for 12mo. The success rate of the operation, postoperative intraocular pressure, the best corrected visual acuity, as well as complications were recorded. RESULTS: The success rate of the operation was 85%. The intraocular pressure of the 27 patients decreased from 48.3±8.3mmHg before operations to 21.4±8.1mmHg(PPCONCLUSION: AGV implantation is characterized by a high success rate, simple operation, less complications and is an effective treatment for refractory glaucoma in adolescents.

  14. Electron tube

    Science.gov (United States)

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  15. Backflushable filter insert

    International Nuclear Information System (INIS)

    Keith, R.C.; Vandenberg, T.; Randolph, M.C.; Lewis, T.B.; Gillis, P.J. Jr.

    1988-01-01

    Filter elements are mounted on a tube plate beneath an accumulator chamber whose wall is extended by skirt and flange to form a closure for the top of pressure vessel. The accumulator chamber is annular around a central pipe which serves as the outlet for filtered water passing from the filter elements. The chamber contains filtered compressed air from supply. Periodically the filtration of water is stopped and vessel is drained. Then a valve is opened, allowing the accumulated air to flow from chamber up a pipe and down pipe, pushing the filtered water from pipe back through the filter elements to clean them. The accumulator chamber is so proportioned, relative to the volume of the system communicating therewith during backflushing, that the equilibrium pressure during backflushing cannot exceed the pressure rating of the vessel. However a line monitors the pressure at the top of the vessel, and if it rises too far a bleed valve is automatically opened to depressurise the system. The chamber is intended to replace the lid of an existing vessel to convert a filter using filter aid to one using permanent filter elements. (author)

  16. Pneumothorax Following Feeding Tube Placement: Precaution and Treatment

    Directory of Open Access Journals (Sweden)

    Morteza Zahmatkesh

    2012-05-01

    Full Text Available Nasojejunal feeding tubes are being used at an increased frequency, but it is not without complications that could be life-threatening. We report two cases of pneumothorax following small-bore feeding tube insertion into the pleural cavity, resulting in pneumothorax. We further discuss the potential measures that can be taken to prevent and treat this serious complication.

  17. Support tube of in-core instruments

    International Nuclear Information System (INIS)

    Suzumura, Takeshi; Saito, Shozo; Yasuda, Tetsuo; Shirosaki, Kiyotaka.

    1975-01-01

    Object: To permit satisfactory output measurement by preventing the bending of a in-core instrument tube within a reactor due to vibrations by means of a spring and thereby preventing mechanical damage of an adjacent fuel channel box. Structure: At a corner of a channel box of a fuel assembly, a in-core instrument tube is arranged along a channel box and has its surface provided with a plurality of removable leaf springs arranged in the direction of axis of the in-core instrument tube and each having an arcular tip. Thus, when the in-core instrument tube is inserted into the reactor, the arcular tip portions of the leaf springs are brought into plane contact with the corner of the channel box so that the in-core instrument tube is elastically supported on the channel box. Thus, there is no possibility of causing damage to the adjacent fuel channel box. (Kamimura, M.)

  18. Lithium insertion in nanostructured titanates

    NARCIS (Netherlands)

    Borghols, W.J.H.

    2010-01-01

    Upon nano-sizing of insertion compounds several significant changes in Li-insertion behavior have been observed for sizes below approximately 50 nm. Although the origins of the phenomena are interrelated, the changes can be divided in three main observations. (1) The formation of new phases, leading

  19. Metallographic study of reconstitution welding in inserts of 1 cm3

    International Nuclear Information System (INIS)

    Romero C, J.; Garcia R, R.; Fernandez T, F.; Perez R, N.; Rocamontes A, M.

    2007-01-01

    In this article, the welding metallographic study carried out in Charpy test tubes reconstituted with notch in 'V', used in the surveillance programs of the vessel in nucleo electric plants is described. Inserts of 1 cm 3 are used, where the inserts are usually rectangular of minimum 18 millimeters of length. The importance of using inserts of 1 cm 3 is that the mechanical properties can be measured in another direction of the vessel steel, when changing the direction or sense of the notch in 'V' or the face where this notch is made in the insert. (Author)

  20. Test manufacturing of copper canisters with cast inserts. Assessment report

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, C.G

    1998-08-01

    The current design of canisters for the deep repository for spent nuclear fuel consists of an outer corrosion-protective copper casing in the form of a tubular section with lid and bottom and an inner pressure-resistant insert. The insert is designed to be manufactured by casting and inside are channels in which the fuel assemblies are to be placed. Over the last years, a number of full-scale manufacturing tests of all canister components have been carried out. The purpose has been to determine and develop the best manufacturing technique and to establish long-term contacts with the best suppliers of material and technology. Part of the work has involved the developing and implementing of a quality assurance system in accordance with ISO 9001, covering the whole chain from suppliers of material up to and including the delivery of assembled canisters. This report consists of a description of the design of the canister together with current drawings and complementary technical specifications stipulating, among other things, requirements placed on different materials. The different manufacturing methods that have been used are also described and commented on in both text and illustrations. For the manufacturing of copper tubes, the roll-forming of rolled plate to tube halves and longitudinal welding is a method that has been tested on a relatively large number of tubes by now, and that probably can be developed into a functioning production method. However, the very promising outcome of performed tests on seamless tube manufacturing, has resulted in a change in direction in tube manufacturing, focusing on continued testing of extrusion as well as pierce and draw processing in the immediate future. In connection with ongoing operations, new manufacturing tests of tubes with less material thickness will be carried out. Test manufacturing of cast inserts has resulted in the choice of nodular iron as material in the continued work. This improvement in design has resulted

  1. Test manufacturing of copper canisters with cast inserts. Assessment report

    International Nuclear Information System (INIS)

    Andersson, C.G.

    1998-08-01

    The current design of canisters for the deep repository for spent nuclear fuel consists of an outer corrosion-protective copper casing in the form of a tubular section with lid and bottom and an inner pressure-resistant insert. The insert is designed to be manufactured by casting and inside are channels in which the fuel assemblies are to be placed. Over the last years, a number of full-scale manufacturing tests of all canister components have been carried out. The purpose has been to determine and develop the best manufacturing technique and to establish long-term contacts with the best suppliers of material and technology. Part of the work has involved the developing and implementing of a quality assurance system in accordance with ISO 9001, covering the whole chain from suppliers of material up to and including the delivery of assembled canisters. This report consists of a description of the design of the canister together with current drawings and complementary technical specifications stipulating, among other things, requirements placed on different materials. The different manufacturing methods that have been used are also described and commented on in both text and illustrations. For the manufacturing of copper tubes, the roll-forming of rolled plate to tube halves and longitudinal welding is a method that has been tested on a relatively large number of tubes by now, and that probably can be developed into a functioning production method. However, the very promising outcome of performed tests on seamless tube manufacturing, has resulted in a change in direction in tube manufacturing, focusing on continued testing of extrusion as well as pierce and draw processing in the immediate future. In connection with ongoing operations, new manufacturing tests of tubes with less material thickness will be carried out. Test manufacturing of cast inserts has resulted in the choice of nodular iron as material in the continued work. This improvement in design has resulted

  2. Fuel assembly and fuel cladding tube

    International Nuclear Information System (INIS)

    Tsutsumi, Shinro; Ito, Ken-ichi; Inagaki, Masatoshi; Nakajima, Junjiro.

    1996-01-01

    A fuel cladding tube is a zirconium liner tube formed by lining a pure zirconium layer on the inner side of a zirconium alloy tube. The fuel cladding tube is formed by extrusion molding of a composite billet formed by inserting a pure zirconium billet into a zirconium alloy billet. Accordingly, the pure zirconium layer and the zirconium alloy tube are strongly joined by metal bond. The fuel cladding tube has an external oxide film on the outer surface of the zirconium alloy tube and an internal oxide film on the inner side of the pure zirconium layer. The external oxide film has a thickness preferably of about 1μm. The internal oxide film has a thickness of not more than 10μm, preferably, from 1 to 5μm. With such a constitution, flaws to be formed on both inner and outer surfaces of the cladding tube upon assembling a fuel assembly can be reduced thereby enabling to reduce the amount of hydrogen absorbed to the cladding tube. (I.N.)

  3. Method of repairing pressure tube type reactors

    International Nuclear Information System (INIS)

    Asada, Takashi.

    1983-01-01

    Purpose: To enable to re-start the reactor operation in a short time, upon occurrence of failures in a pressure tube, as well as directly examine the cause for the failures in the pressure tube. Method: The pressure tube reactor main body comprises a calandria tank of a briquette form, pressure tubes, fuel assemblies and an iron-water shielding body. If failure is resulted to a pressure tube, the reactor operation is at first shutdown and nuclear fuel assemblies are extracted to withdraw from the pressure tube. Then, to an inlet pipe way and an outlet pipeway connected to the failed pressure tube, are attached plugs by means of welding or the like at the appropriate position where the radiation exposure dose is lower and the repairing work can be performed with ease. The pressure tube is disconnected to withdraw from the inlet pipeway and the outlet pipeway and, instead, radiation shielding plug tube is inserted and shield cooling device is actuated if required, wherein the reactor is actuated to re-start the operation. (Yoshino, Y.)

  4. A virtual reality based simulator for learning nasogastric tube placement.

    Science.gov (United States)

    Choi, Kup-Sze; He, Xuejian; Chiang, Vico Chung-Lim; Deng, Zhaohong

    2015-02-01

    Nasogastric tube (NGT) placement is a common clinical procedure where a plastic tube is inserted into the stomach through the nostril for feeding or drainage. However, the placement is a blind process in which the tube may be mistakenly inserted into other locations, leading to unexpected complications or fatal incidents. The placement techniques are conventionally acquired by practising on unrealistic rubber mannequins or on humans. In this paper, a virtual reality based training simulation system is proposed to facilitate the training of NGT placement. It focuses on the simulation of tube insertion and the rendering of the feedback forces with a haptic device. A hybrid force model is developed to compute the forces analytically or numerically under different conditions, including the situations when the patient is swallowing or when the tube is buckled at the nostril. To ensure real-time interactive simulations, an offline simulation approach is adopted to obtain the relationship between the insertion depth and insertion force using a non-linear finite element method. The offline dataset is then used to generate real-time feedback forces by interpolation. The virtual training process is logged quantitatively with metrics that can be used for assessing objective performance and tracking progress. The system has been evaluated by nursing professionals. They found that the haptic feeling produced by the simulated forces is similar to their experience during real NGT insertion. The proposed system provides a new educational tool to enhance conventional training in NGT placement. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Long-term follow-up of otitis media with effusion in children: comparisons between a ventilation tube group and a non-ventilation tube group.

    Science.gov (United States)

    Hong, Hye Ran; Kim, Tae Su; Chung, Jong Woo

    2014-06-01

    The objective of this study was to investigate the long-term outcomes in children with otitis media with effusion who received either medical treatment or ventilation tubes. We retrospectively analyzed the medical records of 89 bilateral cases of otitis media with effusion in children who were recommended to receive ventilation tube insertion and were followed up for more than 5 years. Tympanic membrane was inspected by otoscopic examination. Hearing was evaluated with pure tone audiometry. The mean duration of follow-up was 8.4 years (range, 5.2-15.7 years). Twenty-three children were treated without surgery, while 22 were treated once by ventilation tube insertion and 44 were treated more than once by ventilation tube insertion. At the fifth year of follow-up, both groups of children who underwent ventilation tube insertion had more frequent tympanic membrane abnormalities than the medication group (8.7% in those treated without surgery, 72.7% in those treated once by ventilation tube insertion, and 88.6% in those treated more than once by ventilation tube insertion). Common tympanic membrane abnormalities were retraction (27.0%) and tympanosclerotic plaque (23.6%), regardless of the treatment modality. At the fifth year follow-up, the average air-conduction threshold was 10.0 dB (± 6.5 dB) in patients treated without surgery, 15.9 dB (± 11.2dB) in patients treated once by ventilation tube insertion, and 17.8 dB (± 7.6 dB) in those treated more than once by ventilation tube insertion. The audiological difference was significant when we compared the hearing level of children treated by medication without surgery to the two ventilation tube groups. Though ventilation tube insertion can resolve hearing loss quickly, there were more tympanic membrane abnormalities and a decline in hearing levels in our ventilation tube insertion group vs. the observation group measured 5 years later. Physicians should therefore be cautious when applying a ventilation tube in

  6. photomultiplier tubes

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  7. photomultiplier tube

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  8. Myringotomy versus ventilation tubes in secretory otitis media: eardrum pathology, hearing, and eustachian tube function 25 years after treatment

    DEFF Research Database (Denmark)

    Caye-Thomasen, P.; Stangerup, S.E.; Jorgensen, G.

    2008-01-01

    OBJECTIVE: This report documents the dynamics of eardrum pathology, hearing acuity, and eustachian tube function during 25 years after treatment of bilateral secretory otitis media. The included children were treated by myringotomy on the left ear and ventilation tube insertion on the right ear....... MATERIALS AND METHODS: Two hundred twenty-four children with bilateral secretory otitis media were treated by bilateral myringotomy and insertion of a ventilation tube on the right side only. The children were reexamined by otomicroscopy, tympanometry, and pure tone audiometry after 3, 7, and 25 years...

  9. Root cause of incomplete control rod insertions at Westinghouse reactors

    International Nuclear Information System (INIS)

    Ray, S.

    1997-01-01

    Within the past year, incomplete RCCA insertions have been observed on high burnup fuel assemblies at two Westinghouse PWRs. Initial tests at the Wolf Creek site indicated that the direct cause of the incomplete insertions observed at Wolf Creek was excessive fuel assembly thimble tube distortion. Westinghouse committed to the NRC to perform a root cause analysis by the end of August, 1996. The root cause analysis process used by Westinghouse included testing at ten sites to obtain drag, growth and other characteristics of high burnup fuel assemblies. It also included testing at the Westinghouse hot cell of two of the Wolf Creek incomplete insertion assemblies. A mechanical model was developed to calculate the response of fuel assemblies when subjected to compressive loads. Detailed manufacturing reviews were conducted to determine if this was a manufacturing related issue. In addition, a review of available worldwide experience was performed. Based on the above, it was concluded that the thimble tube distortion observed on the Wolf Creek incomplete insertion assemblies was caused by unusual fuel assembly growth over and above what would typically be expected as a result of irradiation exposure. It was determined that the unusual growth component is a combination of growth due to oxide accumulation and accelerated growth, and would only be expected in high temperature plants on fuel assemblies that see long residence times and high power duties

  10. Use of Mitomycin C to reduce the incidence of encapsulated cysts following ahmed glaucoma valve implantation in refractory glaucoma patients: a new technique.

    Science.gov (United States)

    Zhou, Minwen; Wang, Wei; Huang, Wenbin; Zhang, Xiulan

    2014-09-06

    To evaluate the surgical outcome of Ahmed glaucoma valve (AGV) implantation with a new technique of mitomycin C (MMC) application. This is a retrospective study. All patients with refractory glaucoma underwent FP-7 AGV implantation. Two methods of MMC application were used. In the traditional technique, 6 × 4 mm cotton soaked with MMC (0.25-0.33 mg/ml) was placed in the implantation area for 2-5mins; in the new technique, the valve plate first was encompassed with a thin layer of cotton soaked with MMC, then inserted into the same area. A 200 ml balanced salt solution was applied for irrigation of MMC. The surgical success rate, intraocular pressure (IOP), number of anti-glaucoma medications used, and postoperative complications were analyzed between the groups. The surgical outcomes of two MMC applied techniques were compared. The new technique group had only one case (2.6%) of encapsulated cyst formation out of 38 eyes, while there were eight (19.5%) cases out of 41 eyes the in traditional group. The difference was statistically significant (P = 0.030). According to the definition of success rate, there was 89.5% in the new technique group and 70.7% in the traditional group at the follow-up end point. There was a significant difference between the two groups (P = 0.035). Mean IOP in the new technique group were significantly lower than those of the traditional group at 3 and 6 months (P < 0.05). By using a thin layer of cotton soaked with MMC to encompass the valve plate, the new MMC application technique could greatly decrease the incidence of encapsulated cyst and increase the success rate following AGV implantation.

  11. Effect of mitomycin c and 5-flurouracil adjuvant therapy on the outcomes of Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Cui, Qi N; Hsia, Yen C; Lin, Shan C; Stamper, Robert L; Rose-Nussbaumer, Jennifer; Mehta, Nitisha; Porco, Travis C; Naseri, Ayman; Han, Ying

    2017-03-01

    To examine the effect of mitomycin c and 5-flurouracil on treatment outcomes following Ahmed glaucoma valve implantation. Retrospective consecutive case series. Fifty patients who received Ahmed glaucoma valve implantation from 1999 to 2013 in the San Francisco Veterans Administration Hospital. The +INJECTION group received intraoperative mitomycin c followed by postoperative mitomycin c and/or 5-flurouracil, whereas the -INJECTION group did not. Primary outcome was treatment success at 1 year post-implantation. Intraocular pressure, hypertensive phase, and the number of glaucoma medications were also examined. Twenty-six patients/eyes in the +INJECTION group and 24 patients/eyes in the -INJECTION group were included. Treatment success was higher in the +INJECTION compared with the -INJECTION group (86 vs. 58%; P = 0.04). Intraocular pressure was lower in the +INJECTION compared with the -INJECTION group at 1, 3, 6 and 12 months (P ≪ 0.00001, P = 0.00003, 0.0008 and 0.024). Hypertensive phase occurred less often in the +INJECTION compared with the -INJECTION group (3.8 vs. 54%; P = 0.021). The +INJECTION group required fewer medications compared with the -INJECTION group (P = 0.02, 0.002, 0.003 and 0.008 at 1, 3, 6 and 12 months). Complication rates were comparable between groups (46.2 and 54.2%; P = 0.63). Adjuvant treatment with antifibrotics following Ahmed glaucoma valve implantation decreased the hypertensive phase and improved surgical outcomes without impacting complication rates at 1 year. This study postulates a role for antifibrotics in the postoperative management of Ahmed glaucoma valves. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

  12. [Management of corneal endothelial decompensation with Descemet's membrane endothelial keratoplasty in a patient with Ahmed glaucoma valve implant].

    Science.gov (United States)

    Röck, T; Bartz-Schmidt, K-U; Röck, D; Yoeruek, E

    2014-05-01

    Currently, the main causes for developing bullous keratopathy are from problems related to intraocular surgery, trauma, infection, Fuchs' endothelial dystrophy and chronically elevated intraocular pressure. In the 1990s penetrating keratoplasty was once considered the therapy of choice for treatment of bullous keratopathy but in recent years it has been replaced by posterior lamellar keratoplasty. The Descemet membrane endothelial keratoplasty (DMEK) procedure represents the final development of posterior lamellar keratoplasty. The question now arises whether DMEK can be used in patients with bullous keratopathy and Ahmed glaucoma valve implant. A 72-year-old man was referred to our hospital for further evaluation with the diagnosis of bullous keratopathy and pseudoexfoliative glaucoma. The bullous keratopathy was caused by a variety of previous operations as well as decompensation of intraocular pressure. This article describes the therapy of bullous keratopathy by DMEK with existing Ahmed glaucoma valve implant. After surgery the cornea became clear and the best-corrected visual acuity improved from hand movement to 0.2. The intraocular pressure remained normal (10-14 mmHg) without antiglaucoma medication and the endothelial cell count decreased only slightly over a follow-up of 13 months. No complications were encountered. The DMEK surgical procedure seems to be possible in patients with Ahmed glaucoma valve implant and endothelial decompensation. However, further studies with a larger number of patients should follow to validate the replacement of penetrating keratoplasty and other posterior lamellar procedures by DMEK.

  13. Intraocular pressure control with Ahmed glaucoma drainage device in patients with cicatricial ocular surface disease-associated or aniridia-related glaucoma.

    Science.gov (United States)

    Almousa, Radwan; Lake, Damian B

    2014-08-01

    To analyze the control of intraocular pressure (IOP) with an Ahmed glaucoma drainage device (AGDD) in two groups of glaucoma patients--one with cicatricial ocular surface disease (COSD) and one with aniridia. This is a retrospective comparative case series of nine patients (11 eyes) with COSD and six patients (8 eyes) with aniridia who underwent AGDD surgery to control IOP. The main outcome measure in both groups was stability of IOP between 6 and 21 mmHg. Mean IOP decreased significantly in both groups after AGDD surgery (29.6 ± 8.7 vs 14.7 ± 2.5, p = 0.008 in the COSD group; 26.3 ± 8.2 vs 15.3 ± 5.8, p = 0.008 in the aniridia group). Over a mean post-surgery follow-up of 37.1 months in the COSD group, we managed to control IOP in nine eyes; IOP control was successful in 87 % of eyes at 12 months and 58 % of eyes at 26 months. Over a mean post-surgery follow-up of 37.4 months in the aniridia group, we managed to control the IOP in seven eyes; IOP control was successful in 87 % of eyes at 12 months. AGDD surgery had no significant deleterious effect on visual acuity in either group. A severe complication occurred in one eye (1/8) in the aniridia group (lost vision due to retinal detachment) and in one eye (1/11) in the COSD group (tube exposure). AGDD surgery is effective in controlling IOP and has a low complication rate in COSD and aniridia patients; however, some of the complications are severe and prompt management is needed to prevent deleterious results.

  14. Deadly pressure pneumothorax after withdrawal of misplaced feeding tube

    DEFF Research Database (Denmark)

    Andresen, Erik Nygaard; Frydland, Martin; Usinger, Lotte

    2016-01-01

    BACKGROUND: Many patients have a nasogastric feeding tube inserted during admission; however, misplacement is not uncommon. In this case report we present, to the best of our knowledge, the first documented fatality from pressure pneumothorax following nasogastric tube withdrawal. CASE PRESENTATION......, but our patient died less than an hour after withdrawal. The autopsy report stated that cause of death was tension pneumothorax, which developed following withdrawal of the misplaced feeding tube. CONCLUSIONS: The indications for insertion of nasogastric feeding tubes are many and the procedure...... is considered harmless; however, if the tube is misplaced there is good reason to be cautious on removal as this can unmask puncture of the pleura eliciting pneumothorax and, as this case report shows, result in an ultimately deadly tension pneumothorax....

  15. Method of fabricating a poision tube for reactor control rods

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Yasuhiko; Yoshida, Toshimi; Masaoka, Isao; Naruse, Akisuke

    1983-04-28

    A method to unify the neutron absorbing performance, enhance the workability in the insertion of neutron absorber tube and further decrease the stresses acting on the neutron absorber coating tube is described. The neutron absorber coated rod comprising neutron absorbing substance and a metal pipe is fabricated by compressing a metal pipe filled with the neutron absorber. Specifically, neutron absorbing substance such as boron carbide powder or the like is filled in a metal pipe such as made of stainless steel tube by way of vibration packing or the like. Then, after heating the metal pipe, it is applied with compression working such as swaging into a fine tube to increase the packing density of the absorbing substance filled in the pipe to greater than 60% of the theoretical density and completely contacted closely to the inner wall of the pipe. The neutron absorber coated rod thus fabricated can be inserted to an external coating tube with ease at a predetermined gap.

  16. Intravitreal ranibizumab injection combined trabeculectomy versus Ahmed valve surgery in the treatment of neovascular glaucoma: assessment of efficacy and complications.

    Science.gov (United States)

    Liu, Lan; Xu, Yongfeng; Huang, Zhu; Wang, Xiaoyu

    2016-05-26

    Researches have shown anti-vascular endothelial growth factor (VEGF) agent is effective in treating neovascular eye diseases. The purpose of this study is to evaluate the efficacy and safety of intravitreal ranibizumab (IVR) injection combined trabeculectomy in the treatment of neovascular glaucoma (NVG), and compared it with Ahmed valve surgery. Thirty-six NVG patients (37 eyes) from the First Affiliated Hospital of Zhejiang medical college, between January 1, 2014 and January 31, 2015, were included in this prospective, interventional clinical study. Eighteen NVG eyes were given IVR injection one week before trabeculectomy. Ahmed valve implantation surgery was performed in nineteen eyes. Ocular pain, best corrected visual acuity (BCVA), intraocular pressure (IOP) and surgical complications were evaluated before and after the surgery. IOP was significantly decreased following IVR injection combined trabeculectomy treatment (baseline 57.1 ± 8.9 mmHg; week 1, 15.2 ± 4.3 mmHg p = 0.000; month 1, 16.9 ± 2.1 mmHg p = 0.000; month 3, 20.3 ± 7.7 mmHg p = 0.000; month 6, 19.7 ± 7.3 mmHg p = 0.000). There was a significant, though modest, BCVA improvement in sighted eyes of IVR group (baseline 2.42 ± 0.68, W1 1.80 ± 0.91, P = 0.013; M1 1.77 ± 0.93, p = 0.011). IVR injection combined trabeculectomy had less postoperative complications and lower failure ratio than Ahmed surgery (IVR 5.6 %, Ahmed 31.6 %). The study revealed that IVR injection combined trabeculectomy was an effective and safe treatment for NVG. Compared with Ahmed surgery, IVR injection combined trabeculectomy had less complications and higher success ratio. (Chinese Clinical Registry, TRN ChiCTR-OPN-16008147, 3/24/2016, retrospectively registered).

  17. Computation and measurement of calandria tube sag in PHWR

    International Nuclear Information System (INIS)

    Kim, Tae Ryong; Sohn, Seok Man

    2003-01-01

    Calandria tubes and liquid injection shutdown system (LISS) tubes in a pressurized heavy water reactor (PHWR) is known to sag due to irradiation creep and growth during plant operation. When the sag of calandria tube becomes bigger, the calandria tube possibly comes in contact with LISS tube crossing beneath and calandria tube. The contact subsequently may cause the damage on the calandria tube resulting in unpredicted outage of the plant. It is therefore necessary to check the gap between the two tubes in order to periodically confirm no contact by using a proper measure during the plant life. An ultrasonic gap measuring probe assembly which can be inserted into two viewing ports of the calandria was developed in Korea and utilized to measure the sags of both tubes in the PHWR. It was found that the centerlines of calandria tubes and liquid injection shutdown system tubes can be precisely detected by ultrasonic wave. The gaps between two tubes were easily obtained from the relative distance of the measured centerline elevations of the tubes. Based on the irradiation creep equation and the measurement data, a computer program to calculate the sags was also developed. With the computer program, the sag at the end of plant life was predicted. (author)

  18. Psyche, Nightmare and Religion: Precursors of Colonial Conquest in Ahmed Yerima’s Attahiru

    Directory of Open Access Journals (Sweden)

    Taiwo A. Stanley Osanyemi

    2017-06-01

    Full Text Available This paper is premised on the connection between history and drama in order to profile the historical characters or heroes and explicate the socio-political predicament in their society. Existing studies on historical plays have focused on the celebration and chronicling of the heroic deeds of the historical characters, sometimes ignoring the artistic techniques the playwright employed. This study, therefore, examines psyche, nightmare and religion as the stylistic techniques for establishing the sources of disintegration in an imperial environment. This is with a view to investigating the link between the conflicts of the protagonist and the predicaments of his society. The study is based on psychoanalysis that allows for the investigation of characters’ unconscious motives and collective archetypes. The text, Attahiru is subjected to critical textual analysis in both content and form to analyse the paradigmatic use of history, dream and religion to account for the colonial conquest of an African society. Various patterns of unconscious archetypes such as psyche, nightmare, daydream and religion were discovered to serve as techniques of foreshadowing and flashback to the physical and psychological conflicts in the play. They serve as signifiers of the protagonist’s traumas. These unconscious archetypes, therefore, have become the catalysts for disintegration and veritable strategy in Ahmed Yerima’s account of imperial history.

  19. Ahmed glaucoma valve in post-penetrating-keratoplasty glaucoma: A critically evaluated prospective clinical study

    Directory of Open Access Journals (Sweden)

    Anita Panda

    2011-01-01

    Full Text Available Aim: The aim was to evaluate the outcome of Ahmed glaucoma valve (AGV in post-penetrating-keratoplasty glaucoma (PKPG. Materials and Methods: In this prospective study, 20 eyes of 20 adult patients with post-PKPG with intraocular pressure (IOP >21 mmHg, on two or more antiglaucoma medications, underwent AG (model FP7 implantation and were followed up for a minimum of 6 months. Absolute success was defined as 5 < IOP < 21 mmHg and qualified success as 5 < IOP < 21 mmHg with medications or minor procedures. Results: The mean IOP decreased from 42.95 ± 10.24 to 17.69 ± 3.64 mmHg (P < 0.001 and the use of medications dropped from 2.92 to 0.39 (P < 0.001 after AGV implantation. The absolute success was achieved in 11 eyes and qualified success in 9. There was no significant change in best corrected visual acuity, graft clarity, or graft thickness. Six device-related complications occurred after AGV implantations which were successfully managed with medical or minor surgical therapy. Conclusions: Postkeratoplasty refractory glaucoma managed by AGV implantation revealed a satisfactory outcome up to 6 months of follow-up.

  20. Incidence of nutritional anaemia among the under five children attending Ahmed Gasim hospital

    International Nuclear Information System (INIS)

    Mohamed, Hager Elrasheed Ali

    1998-11-01

    A survey was carried out in Khartoum North Ahmed Gasim specialist Hospital for children to identify aetiological factors that lead to incidence of nutritional anaemia among children under under five years of age. The sample consists of 192 patients taken from the hospital wards (experimental group), and 60 healthy children taken from out patient vaccination department of same hospital. A questionnaire was used as a tool for collection data regarding children and their families with emphasis to general information, socio-economic information, dietary information, anthropometric information, medical history and laboratory investigations including haemoglobin, hematocrit (PCV)%, peripheral blood picture, serum ferritin, serum folate and serum B 12 . Results show no correlation between anaemia and age R(0.1048) p 1 2 deficiency. Some children affected had mixed deficiency anaemia (3.182). Iron deficiency without anaemia was common among healthy children (control) 22.8%. Some recommendations were set for the improvement of the existing situation e.g. health education, nutrition education with emphasis on intake of supplements and weaning diets rich in iron and folate. Follow up and surveillance program to compact nutritional anaemia should be adopted.(Author)

  1. Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure

    Science.gov (United States)

    Huang, Jingjing; Lin, Jialiu; Wu, Ziqiang; Xu, Hongzhi; Zuo, Chengguo; Ge, Jian

    2015-01-01

    Purpose The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve (AGV) implantation in patients less than 7 years of age, with advanced primary congenital glaucoma who have failed previous surgeries. Patients and methods Consecutive patients with advanced primary congenital glaucoma that failed previous operations and had undergone subsequent AGV implantation were evaluated retrospectively. Surgical success was defined as 1) intraocular pressure (IOP) ≥6 and ≤21 mmHg; 2) IOP reduction of at least 30% relative to preoperative values; and 3) without the need for additional surgical intervention for IOP control, loss of light perception, or serious complications. Results Fourteen eyes of eleven patients were studied. Preoperatively, the average axial length was 27.71±1.52 (25.56–30.80) mm, corneal diameter was 14.71±1.07 (13.0–16.0) mm, cup-to-disc ratio was 0.95±0.04 (0.9–1.0), and IOP was 39.5±5.7 (30–55) mmHg. The mean follow-up time was 18.29±10.96 (5–44, median 18) months. There were significant reductions in IOPs and the number of glaucoma medications (Pglaucoma unresponsive to previous surgical intervention, despite a relatively high incidence of severe surgical complications. PMID:26082610

  2. Initial Experience With the New Ahmed Glaucoma Valve Model M4: Short-term Results.

    Science.gov (United States)

    Cvintal, Victor; Moster, Marlene R; Shyu, Andrew P; McDermott, Katie; Ekici, Feyzahan; Pro, Michael J; Waisbourd, Michael

    2016-05-01

    To evaluate the clinical outcomes of the new Ahmed glaucoma valve (AGV) model M4. The device consists of a porous polyethylene shell designed for improved tissue integration and reduced encapsulation of the plate for better intraocular pressure (IOP) control. Medical records of patients with an AGV M4 implantation between December 1, 2012 and December 31, 2013 were reviewed. The main outcome measure was surgical failure, defined as either (1) IOP21 mm Hg and/or glaucoma, and/or (3) loss of light perception. Seventy-five eyes of 73 patients were included. Postoperative IOP at all follow-up visits significantly decreased from a baseline IOP of 31.2 mm Hg (P<0.01). However, IOP increased significantly at 3 months (20.4 mm Hg), 6 months (19.3 mm Hg), and 12 months (20.3 mm Hg) compared with 1 month (13.8 mm Hg) postoperatively (P<0.05). At 6 months and 1 year, the cumulative probability of failure was 32% and 72%, respectively. The AGV M4 effectively reduced IOP in the first postoperative month, but IOP steadily increased thereafter. Consequently, failure rates were high after 1 year of follow-up.

  3. Surgical Outcomes of Additional Ahmed Glaucoma Valve Implantation in Refractory Glaucoma.

    Science.gov (United States)

    Ko, Sung Ju; Hwang, Young Hoon; Ahn, Sang Il; Kim, Hwang Ki

    2016-06-01

    To evaluate the surgical outcomes of the implantation of an additional Ahmed glaucoma valve (AGV) into the eyes of patients with refractory glaucoma following previous AGV implantation. This study is a retrospective review of the clinical histories of 23 patients who had undergone a second AGV implantation after a failed initial implantation. Age, sex, prior surgery, glaucoma type, number of medications, intraocular pressure (IOP), visual acuity, and surgical complications were analyzed. Surgical success was defined as IOP maintained below 21 mm Hg, with at least a 20% overall reduction in IOP, regardless of the use of IOP-lowering medications. Following the implantation of a second AGV, the mean IOP decreased from 39.3 to 18.5 mm Hg (52.9% reduction, P<0.001). The mean number of postoperative IOP-lowering medications administered decreased from 2.8 to 1.7 after the second AGV implantation (P<0.001). The cumulative probability of success for the procedure was 87% after 1 year and 52% after 3 years. Three patients (13.0%) experienced bullous keratopathy after the second AGV implantation. None of the patients showed any evidence of diplopia or ocular movement limitation as a result of the presence of 2 AGVs in the same eye. Prior trabeculectomy was found to be a significant risk factor for failure (P=0.027). A second AGV implantation can be a good choice of surgical treatment when the first AGV has failed to control IOP.

  4. Trabeculectomy with Ex-PRESS implant versus Ahmed glaucoma valve implantation-a comparative study

    Science.gov (United States)

    Waisbourd, Michael; Fischer, Naomi; Shalev, Hadas; Spierer, Oriel; Ben Artsi, Elad; Rachmiel, Rony; Shemesh, Gabi; Kurtz, Shimon

    2016-01-01

    AIM To compare the surgical outcomes of trabeculectomy with Ex-PRESS implant and Ahmed glaucoma valve (AGV) implantation. METHODS Patients who underwent trabeculectomy with Ex-PRESS implants or AGV implantation separately were included in this retrospective chart review. Main outcome measures were surgical failure and complications. Failure was defined as intraocular pressure (IOP) >21 mm Hg or glaucoma, or loss of light perception. Eyes that had not failed were considered as complete success if they did not required supplemental medical therapy. RESULTS A total of 64 eyes from 57 patients were included: 31 eyes in the Ex-PRESS group and 33 eyes in the AGV group. The mean follow-up time was 2.6±1.1y and 3.3±1.6y, respectively. Patients in the AGV group had significantly higher baseline mean IOP (P=0.005), lower baseline mean visual acuity (VA) (P=0.02), and higher proportion of patients with history of previous trabeculectomy (Pglaucoma surgeries. Therefore, the results are limited to the cohort included in this study. PMID:27803857

  5. Eustachian tube patency

    Science.gov (United States)

    Eustachian tube patency refers to how much the eustachian tube is open. The eustachian tube runs between the middle ear and the throat. It controls the pressure behind the eardrum and middle ear space. This helps keep ...

  6. Feeding tube - infants

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007235.htm Feeding tube - infants To use the sharing features on this page, please enable JavaScript. A feeding tube is a small, soft, plastic tube placed ...

  7. Process and device for locating a defective tube, particularly in the tube bundle of a steam generator

    International Nuclear Information System (INIS)

    Denis, Jean.

    1977-01-01

    A process is described for locating a defective tube, particularly in the tube bundle of a steam generator of the reversed U tube kind with the ends connected to a tube plate, marking with the bottom of the generator casing a space separated into two adjacent collectors, respectively for the inlet and outlet of a primary fluid flowing inside the tubes of the bundle, these being externally washed by a secondary vaporizing fluid. In this process a television camera that can be inserted into the casing is used. This process consists in transmitting to a display system outside the generator an image of the tube plate in each collector by means of a directional television camera and then to place over this image a luminous marker to locate the end or the faulty tube [fr

  8. Tube holding system

    International Nuclear Information System (INIS)

    Cunningham, R.C.

    1978-01-01

    A tube holding rig is described for the lateral support of tubes arranged in tight parcels in a heat exchanger. This tube holding rig includes not less than two tube supporting assemblies, with a space between them, located crosswise with respect to the tubes, each supporting assembly comprising a first set of parallel components in contact with the tubes, whilst a second set of components is also in contact with the tubes. These two sets of parts together define apertures through which the tubes pass [fr

  9. AHM1, a Novel Type of Nuclear Matrix–Localized, MAR Binding Protein with a Single AT Hook and a J Domain–Homologous Region

    Science.gov (United States)

    Morisawa, Gaku; Han-yama, Atsushi; Moda, Ichiro; Tamai, Atsushi; Iwabuchi, Masaki; Meshi, Tetsuo

    2000-01-01

    Interactions between the nuclear matrix and special regions of chromosomal DNA called matrix attachment regions (MARs) have been implicated in various nuclear functions. We have identified a novel protein from wheat, AT hook–containing MAR binding protein1 (AHM1), that binds preferentially to MARs. A multidomain protein, AHM1 has the special combination of a J domain–homologous region and a Zn finger–like motif (a J-Z array) and an AT hook. For MAR binding, the AT hook at the C terminus was essential, and an internal portion containing the Zn finger–like motif was additionally required in vivo. AHM1 was found in the nuclear matrix fraction and was localized in the nucleoplasm. AHM1 fused to green fluorescent protein had a speckled distribution pattern inside the nucleus. AHM1 is most likely a nuclear matrix component that functions between intranuclear framework and MARs. J-Z arrays can be found in a group of (hypothetical) proteins in plants, which may share some functions, presumably to recruit specific Hsp70 partners as co-chaperones. PMID:11041885

  10. LOFT voltage insertion calibaration program

    International Nuclear Information System (INIS)

    Tillitt, D.N.; Miyasaki, F.S.

    1975-08-01

    The Loss-of-Fluid Test (LOFT) Facility is an experimental facility built around a ''scaled'' version of a large pressurized water reactor (LPWR). Part of this facility is the Data Acquisition and Visual Display System (DAVDS) as defined by the LOFT System Design Document SDD 1.4.2C. The DAVDS has a 702 data channel recording capability of which 548 are recorded digitally. The DAVDS also contains a Voltage Insertion Calibration Subsystem used to inject precise and known voltage steps into the recording systems. The computer program that controls the Voltage Insertion Calibration Subsystem is presented. 7 references. (auth)

  11. Tube Thoracostomy: Complications and Its Management

    Directory of Open Access Journals (Sweden)

    Emeka B. Kesieme

    2012-01-01

    Full Text Available Background. Tube thoracostomy is widely used throughout the medical, surgical, and critical care specialities. It is generally used to drain pleural collections either as elective or emergency. Complications resulting from tube thoracostomy can occasionally be life threatening. Aim. To present an update on the complications and management of complications of tube thoracostomy. Methods. A review of the publications obtained from Medline search, medical libraries, and Google on tube thoracostomy and its complications was done. Results. Tube thoracostomy is a common surgical procedure which can be performed by either the blunt dissection technique or the trocar technique. Complication rates are increased by the trocar technique. These complications have been broadly classified as either technical or infective. Technical causes include tube malposition, blocked drain, chest drain dislodgement, reexpansion pulmonary edema, subcutaneous emphysema, nerve injuries, cardiac and vascular injuries, oesophageal injuries, residual/postextubation pneumothorax, fistulae, tumor recurrence at insertion site, herniation through the site of thoracostomy, chylothorax, and cardiac dysrhythmias. Infective complications include empyema and surgical site infection. Conclusion. Tube thoracostomy, though commonly performed is not without risk. Blunt dissection technique has lower risk of complications and is hence recommended.

  12. Tube Thoracostomy: Complications and Its Management

    Science.gov (United States)

    Kesieme, Emeka B.; Dongo, Andrew; Ezemba, Ndubueze; Irekpita, Eshiobo; Jebbin, Nze; Kesieme, Chinenye

    2012-01-01

    Background. Tube thoracostomy is widely used throughout the medical, surgical, and critical care specialities. It is generally used to drain pleural collections either as elective or emergency. Complications resulting from tube thoracostomy can occasionally be life threatening. Aim. To present an update on the complications and management of complications of tube thoracostomy. Methods. A review of the publications obtained from Medline search, medical libraries, and Google on tube thoracostomy and its complications was done. Results. Tube thoracostomy is a common surgical procedure which can be performed by either the blunt dissection technique or the trocar technique. Complication rates are increased by the trocar technique. These complications have been broadly classified as either technical or infective. Technical causes include tube malposition, blocked drain, chest drain dislodgement, reexpansion pulmonary edema, subcutaneous emphysema, nerve injuries, cardiac and vascular injuries, oesophageal injuries, residual/postextubation pneumothorax, fistulae, tumor recurrence at insertion site, herniation through the site of thoracostomy, chylothorax, and cardiac dysrhythmias. Infective complications include empyema and surgical site infection. Conclusion. Tube thoracostomy, though commonly performed is not without risk. Blunt dissection technique has lower risk of complications and is hence recommended. PMID:22028963

  13. Fixed mask assembly research for APS insertion devices

    International Nuclear Information System (INIS)

    Kuzay, T.M.

    1992-01-01

    The Fixed Mask Assembly (FMA) is the first component to interact with the photon beam. Two sets of a pair of FMA channels, vertically and horizontally disposed, contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice, the FMA channels are made of heavy, seamless copper, have rectangular cross-sections, and are cooled internally with water. Channels are set at grazing angles ranging from I to 6 degrees with respect to the beam, depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAS. Therefore, a need exists to improve the FMA engineering, keeping in mind the current design criteria and philosophy of FMAS. Preliminary analysis of current heat transfer practice indicates that the major resistance to heat transfer is on the coolant side. Therefore, FMA cooling would benefit from enhanced heat transfer on the coolant side. With this principle in mind, an experimental program has been undertaken to explore the feasibility of using high-performance copper tube configurations which are expected to yield heat transfer coefficients, open-quotes hclose quotes, in single phase flow systems 2 to 5(?) times higher than equivalent plain tubes. In this report, the experimental scope and a preliminary analysis of high-performance copper tube configurations are described

  14. Summary of experimental insertions workshop

    International Nuclear Information System (INIS)

    Sandweiss, J.; Month, M.

    1976-01-01

    An ISABELLE workshop of the summer 1976 series, which was held at Brookhaven August 16--20, focused on the design and utilization of the experimental insertions. The goals of the workshop are outlined, and a few general remarks about the results are presented

  15. Concepts for stereoselective acrylate insertion

    KAUST Repository

    Neuwald, Boris

    2013-01-23

    Various phosphinesulfonato ligands and the corresponding palladium complexes [{((PaO)PdMeCl)-μ-M}n] ([{( X1-Cl)-μ-M}n], (PaO) = κ2- P,O-Ar2PC6H4SO2O) with symmetric (Ar = 2-MeOC6H4, 2-CF3C6H4, 2,6-(MeO)2C6H3, 2,6-(iPrO)2C 6H3, 2-(2′,6′-(MeO)2C 6H3)C6H4) and asymmetric substituted phosphorus atoms (Ar1 = 2,6-(MeO)2C6H 3, Ar2 = 2′-(2,6-(MeO)2C 6H3)C6H4; Ar1 = 2,6-(MeO)2C6H3, Ar2 = 2-cHexOC 6H4) were synthesized. Analyses of molecular motions and dynamics by variable temperature NMR studies and line shape analysis were performed for the free ligands and the complexes. The highest barriers of ΔGa = 44-64 kJ/mol were assigned to an aryl rotation process, and the flexibility of the ligand framework was found to be a key obstacle to a more effective stereocontrol. An increase of steric bulk at the aryl substituents raises the motional barriers but diminishes insertion rates and regioselectivity. The stereoselectivity of the first and the second methyl acrylate (MA) insertion into the Pd-Me bond of in situ generated complexes X1 was investigated by NMR and DFT methods. The substitution pattern of the ligand clearly affects the first MA insertion, resulting in a stereoselectivity of up to 6:1 for complexes with an asymmetric substituted phosphorus. In the consecutive insertion, the stereoselectivity is diminished in all cases. DFT analysis of the corresponding insertion transition states revealed that a selectivity for the first insertion with asymmetric (P aO) complexes is diminished in the consecutive insertions due to uncooperatively working enantiomorphic and chain end stereocontrol. From these observations, further concepts are developed. © 2012 American Chemical Society.

  16. New Technique of Exposed Glaucoma Drainage Tube Repair: Report of a Case.

    Science.gov (United States)

    Berezina, Tamara L; Fechtner, Robert D; Cohen, Amir; Kim, Eliott E; Chu, David S

    2015-01-01

    We present the case of successful repair of an exposed glaucoma drainage tube by cornea graft fixation with tissue adhesive, and without subsequent coverage by adjacent conjunctiva or donor tissues. Patient with history of keratoglobus with thin cornea and sclera, and phthisical contralateral eye, underwent three unsuccessful corneal grafts followed by Boston type 1 keratoprosthesis in the right eye. Ahmed drainage device with sclera patch graft was implanted to control the intraocular pressure. Two years later the tube eroded through sclera graft and conjunctiva. Repair was performed by covering the tube with a corneal patch graft secured by tissue adhesive after the conjunctiva in this area was dissected away. The cornea graft was left uncovered due to fragility of adjacent conjunctiva. The healing of ocular and graft surfaces was complete prior to the 1 month follow-up. Conjunctival epithelium covered the corneal patch graft. At 12 months follow-up, the graft and the tube remained stable. Our report suggests that corneal patch graft fixation to the sclera by means of tissue adhesive, without closing the conjunctiva, can be considered as an effective alternative surgical approach for managing exposed glaucoma drainage tube, accompanied by adjacent conjunctiva tissue deficiency. How to cite this article: Berezina TL, Fechtner RD, Cohen A, Kim EE, Chu DS. New Technique of Exposed Glaucoma Drainage Tube Repair: Report of a Case. J Curr Glaucoma Pract 2015;9(2):62-64.

  17. Efficacy and safety of intravitreal bevacizumab in eyes with neovascular glaucoma undergoing Ahmed glaucoma valve implantation: 2-year follow-up.

    Science.gov (United States)

    Arcieri, Enyr S; Paula, Jayter S; Jorge, Rodrigo; Barella, Kleyton A; Arcieri, Rafael S; Secches, Danilo J; Costa, Vital P

    2015-02-01

    To evaluate the efficacy and safety of intravitreal bevacizumab (IVB) in eyes with neovascular glaucoma (NVG) undergoing Ahmed glaucoma valve (AGV) implantation. This was a multicentre, prospective, randomized clinical trial that enrolled 40 patients with uncontrolled neovascular glaucoma that had undergone panretinal photocoagulation and required glaucoma drainage device implantation. Patients were randomized to receive IVB (1.25 mg) or not during Ahmed valve implant surgery. Injections were administered intra-operatively, and 4 and 8 weeks after surgery. After a mean follow-up of 2.25 ± 0.67 years (range 1.5-3 years), both groups showed a significant decrease in IOP (p glaucoma undergoing Ahmed glaucoma valve implantation. There is a trend to slightly lower IOPs and number of medications with IVB use during AGV implantation for neovascular glaucoma. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. Histopathologic and immunohistochemical features of capsular tissue around failed Ahmed glaucoma valves.

    Directory of Open Access Journals (Sweden)

    Alka Mahale

    Full Text Available Impervious encapsulation around Ahmed glaucoma valve (AGV results in surgical failure raising intraocular pressure (IOP. Dysregulation of extracellular matrix (ECM molecules and cellular factors might contribute to increased hydraulic resistance to aqueous drainage. Therefore, we examined these molecules in failed AGV capsular tissue. Immunostaining for ECM molecules (collagen I, collagen III, decorin, lumican, chondroitin sulfate, aggrecan and keratan sulfate and cellular factors (αSMA and TGFβ was performed on excised capsules from failed AGVs and control tenon's tissue. Staining intensity of ECM molecules was assessed using Image J. Cellular factors were assessed based on positive cell counts. Histopathologically two distinct layers were visible in capsules. The inner layer (proximal to the AGV showed significant decrease in most ECM molecules compared to outer layer. Furthermore, collagen III (p = 0.004, decorin (p = 0.02, lumican (p = 0.01 and chondroitin sulfate (p = 0.02 was significantly less in inner layer compared to tenon's tissue. Outer layer labelling however was similar to control tenon's for most ECM molecules. Significantly increased cellular expression of αSMA (p = 0.02 and TGFβ (p = 0.008 was detected within capsular tissue compared to controls. Our results suggest profibrotic activity indicated by increased αSMA and TGFβ expression and decreased expression of proteoglycan (decorin and lumican and glycosaminoglycans (chondroitin sulfate. Additionally, we observed decreased collagen III which might reflect increased myofibroblast contractility when coupled with increased TGFβ and αSMA expression. Together these events lead to tissue dysfunction potentially resulting in hydraulic resistance that may affect aqueous flow through the capsular wall.

  19. Outcomes of Ahmed valve surgery for refractory glaucoma in Dhahran, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Tariq Alasbali

    2015-06-01

    Full Text Available AIM:To evaluate the outcomes of Ahmed glaucoma valve (AGV implantation surgery for refractory glaucoma.METHODS:This one-armed historical cohort study was conducted in 2011. Refractory glaucoma was defined as eyes with an intraocular pressure (IOP greater than 21 mm Hg with maximally tolerated glaucoma medications, failed surgeries, or both. For all eyes with refractory glaucoma that underwent AGV implantation, data were collected on IOP, the best corrected visual acuity (BCVA and glaucoma medications preoperatively and 4, 6, 12, 24 and 56wk postoperatively. Logarithm values of IOP were calculated and compared.RESULTS: The study group was comprised of 30 patients (30 eyes, 16 males and 14 females with refractory glaucoma. Mean preoperative IOP was 39.3±13.8 mm Hg. Postoperative mean IOP was 15.7±7.1 mm Hg, 19.6±12.8 mm Hg and 13.9±14.2 mm Hg at 12, 24 and 56wk respectively. BCVA was ≥ 6/60 in 11 eyes preoperatively, and five eyes had BCVA≥6/60 at 56wk postoperatively. Preoperatively, more than four medications were used to treat glaucoma in 21 eyes. At 12wk postoperatively, no medications were required to control IOP in 20 eyes. At 56wk postoperatively, at least one medication was required to control IOP in 10 eyes. Over the entire follow up period, four eyes were treated with yttrium aluminium garnet (YAG laser and 14 eyes required a second surgery. The AGV was removed in four eyes.CONCLUSION: AGV implantation reduced IOP and the number of medications required to control refractory glaucoma. However, there was a higher risk of decreased vision. Long-term follow up and prompt intervention are recommended.

  20. Long-term clinical outcomes of Ahmed valve implantation in patients with refractory glaucoma.

    Directory of Open Access Journals (Sweden)

    Chang Kyu Lee

    Full Text Available To evaluate the long-term efficacy of intraocular pressure (IOP reduction and complications of Ahmed Glaucoma Valve (AGV implantation in patients with refractory glaucoma.Retrospective study.The study involved 302 refractory glaucoma patients who underwent AGV implantation and had a minimum follow-up of 6 months between March 1995 and December 2013.An operation was defined as successful when (1 the postoperative IOP remained between 5 and 21 mmHg and was reduced 30% compared to the baseline IOP with or without medication, (2 there was no loss of light perception or vision-threatening severe complications, and (3 no additional filtering or aqueous drainage surgery was required. Clinical records were reviewed.IOP, anti-glaucoma medications, and complications.The mean follow-up period was 62.25 months (range, 6 to 190 months. The cumulative probability of success was 89% at 6 months, 81% at 1 year, 66% at 3 years, 44% at 10 years, and 26% at 15 years. IOP was reduced from a mean of 32.2 ± 10.5 mmHg to 18.6 ± 9.1 mmHg at 1 month, 15.2 ± 7.0 mmHg at 6 months, and 14.2 ± 3.5 mmHg at 15 years. Surgical failures were significantly increased when preoperative IOP was high, and when severe complications occurred after AGV implantation (P < 0.05.AGV implantation was successful for IOP control in patients with refractive glaucoma in the long term. However, the success rate of surgery decreased over time. Preoperative high IOP and severe complications related to the operation were significant risk factors for failure.

  1. Combined Ahmed Glaucoma Valve Placement, Intravitreal Fluocinolone Acetonide Implantation and Cataract Extraction for Chronic Uveitis.

    Science.gov (United States)

    Chang, Ingrid T; Gupta, Divakar; Slabaugh, Mark A; Vemulakonda, Gurunadh A; Chen, Philip P

    2016-10-01

    To report the outcomes of combined Ahmed glaucoma valve (AGV) placement, intravitreal fluocinolone acetonide implant, and cataract extraction procedure in the treatment of chronic noninfectious uveitis. Retrospective case series of patients with chronic noninfectious uveitis who underwent AGV placement, intravitreal fluocinolone acetonide implantation, and cataract extraction in a single surgical session performed at 1 institution from January 2009 to November 2014. Outcome measures included intraocular pressure (IOP) and glaucoma medication use. Secondary outcome measures included visual acuity, systemic anti-inflammatory medications, number of uveitis flares, and complications. Fifteen eyes of 10 patients were studied, with a mean age of 40.3±15.7 and mean follow-up duration of 26 months (range, 13 to 39 mo). Before surgery, the IOP was 18.5±7.3 mm Hg and patients were using 1.5±1.5 topical glaucoma medications. At the 12-month follow-up, IOP was 12.8±3.2 mm Hg (P=0.01) and patients were using 0.5±0.8 (P=0.03) topical glaucoma medications. At 36 months of follow-up, late, nonsustained hypotony had occurred in 3 eyes (20%), and 1 eye (6%) had received a second AGV for IOP control. Before treatment, patients had 2.7±1.5 uveitis flares in the year before surgery while on an average of 2.1±0.6 systemic anti-inflammatory medications, which decreased to an average of 0.1±0.3 (Pglaucoma medications at 12 months after treatment in patients with chronic uveitis.

  2. Histopathologic and immunohistochemical features of capsular tissue around failed Ahmed glaucoma valves.

    Science.gov (United States)

    Mahale, Alka; Fikri, Fatma; Al Hati, Khitam; Al Shahwan, Sami; Al Jadaan, Ibrahim; Al Katan, Hind; Khandekar, Rajiv; Maktabi, Azza; Edward, Deepak P

    2017-01-01

    Impervious encapsulation around Ahmed glaucoma valve (AGV) results in surgical failure raising intraocular pressure (IOP). Dysregulation of extracellular matrix (ECM) molecules and cellular factors might contribute to increased hydraulic resistance to aqueous drainage. Therefore, we examined these molecules in failed AGV capsular tissue. Immunostaining for ECM molecules (collagen I, collagen III, decorin, lumican, chondroitin sulfate, aggrecan and keratan sulfate) and cellular factors (αSMA and TGFβ) was performed on excised capsules from failed AGVs and control tenon's tissue. Staining intensity of ECM molecules was assessed using Image J. Cellular factors were assessed based on positive cell counts. Histopathologically two distinct layers were visible in capsules. The inner layer (proximal to the AGV) showed significant decrease in most ECM molecules compared to outer layer. Furthermore, collagen III (p = 0.004), decorin (p = 0.02), lumican (p = 0.01) and chondroitin sulfate (p = 0.02) was significantly less in inner layer compared to tenon's tissue. Outer layer labelling however was similar to control tenon's for most ECM molecules. Significantly increased cellular expression of αSMA (p = 0.02) and TGFβ (p = 0.008) was detected within capsular tissue compared to controls. Our results suggest profibrotic activity indicated by increased αSMA and TGFβ expression and decreased expression of proteoglycan (decorin and lumican) and glycosaminoglycans (chondroitin sulfate). Additionally, we observed decreased collagen III which might reflect increased myofibroblast contractility when coupled with increased TGFβ and αSMA expression. Together these events lead to tissue dysfunction potentially resulting in hydraulic resistance that may affect aqueous flow through the capsular wall.

  3. Adjunctive Mitomycin C or Amniotic Membrane Transplantation for Ahmed Glaucoma Valve Implantation: A Randomized Clinical Trial.

    Science.gov (United States)

    Yazdani, Shahin; Mahboobipour, Hassan; Pakravan, Mohammad; Doozandeh, Azadeh; Ghahari, Elham

    2016-05-01

    To determine whether adjunctive mitomycin C (MMC) or amniotic membrane transplantation (AMT) improve the outcomes of Ahmed glaucoma valve (AGV) implantation. This double-blind, stratified, 3-armed randomized clinical trial includes 75 eyes of 75 patients aged 7 to 75 years with refractory glaucoma. Eligible subjects underwent stratified block randomization; eyes were first stratified to surgery in the superior or inferior quadrants based on feasibility; in each subgroup, eyes were randomly assigned to the study arms using random blocks: conventional AGV implantation (group A, 25 eyes), AGV with MMC (group B, 25 eyes), and AGV with AMT (group C, 25 eyes). The 3 study groups were comparable regarding baseline characteristics and mean follow-up (P=0.288). A total of 68 patients including 23 eyes in group A, 25 eyes in group B, and 20 eyes group C completed the follow-up period and were analyzed. Intraocular pressure was lower in the MMC group only 3 weeks postoperatively (P=0.04) but comparable at other time intervals. Overall success rate was comparable in the 3 groups at 12 months (P=0.217). The number of eyes requiring medications (P=0.30), time to initiation of medications (P=0.13), and number of medications (P=0.22) were comparable. Hypertensive phase was slightly but insignificantly more common with standard surgery (82%) as compared with MMC-augmented (60%) and AMT-augmented (70%) procedures (P=0.23). Complications were comparable over 1 year (P=0.28). Although adjunctive MMC and AMT were safe during AGV implantation, they did not influence success rates or intraocular pressure outcomes. Complications, including hypertensive phase, were also comparable.

  4. Long-term clinical outcomes of Ahmed valve implantation in patients with refractory glaucoma.

    Science.gov (United States)

    Lee, Chang Kyu; Ma, Kyoung Tak; Hong, Young Jae; Kim, Chan Yun

    2017-01-01

    To evaluate the long-term efficacy of intraocular pressure (IOP) reduction and complications of Ahmed Glaucoma Valve (AGV) implantation in patients with refractory glaucoma. Retrospective study. The study involved 302 refractory glaucoma patients who underwent AGV implantation and had a minimum follow-up of 6 months between March 1995 and December 2013. An operation was defined as successful when (1) the postoperative IOP remained between 5 and 21 mmHg and was reduced 30% compared to the baseline IOP with or without medication, (2) there was no loss of light perception or vision-threatening severe complications, and (3) no additional filtering or aqueous drainage surgery was required. Clinical records were reviewed. IOP, anti-glaucoma medications, and complications. The mean follow-up period was 62.25 months (range, 6 to 190 months). The cumulative probability of success was 89% at 6 months, 81% at 1 year, 66% at 3 years, 44% at 10 years, and 26% at 15 years. IOP was reduced from a mean of 32.2 ± 10.5 mmHg to 18.6 ± 9.1 mmHg at 1 month, 15.2 ± 7.0 mmHg at 6 months, and 14.2 ± 3.5 mmHg at 15 years. Surgical failures were significantly increased when preoperative IOP was high, and when severe complications occurred after AGV implantation (P glaucoma in the long term. However, the success rate of surgery decreased over time. Preoperative high IOP and severe complications related to the operation were significant risk factors for failure.

  5. The Ahmed shunt versus the Baerveldt shunt for refractory glaucoma: a meta-analysis.

    Science.gov (United States)

    Wang, Shiming; Gao, Xiaoming; Qian, Nana

    2016-06-08

    The purpose of this study was to compare the efficacy and tolerability of the Ahmed glaucoma valve (AGV) implant and the Baerveldt implant for the treatment of refractory glaucoma. We comprehensively searched four databases, including PubMed, EMBASE, Web of Science, and the Cochrane Library databases, selecting the relevant studies. The continuous variables, namely, intraocular pressure reduction (IOPR) and a reduction in glaucoma medication, were pooled by the weighted mean differences (WMDs), and the dichotomous outcomes, including success rates and tolerability estimates, were pooled by the odds ratio (ORs). A total of 929 patients from six studies were included. The WMDs of the IOPR between the AGV implant and the Baerveldt implant were 1.58 [95 % confidence interval (CI): -2.99 to 6.15] at 6 months, -1.01 (95 % CI: -3.40 to 1.98) at 12 months, -0.54 (95 % CI: -4.89 to 3.82) at 24 months, and -0.47 (95 % CI: -3.29 to 2.35) at 36 months. No significant difference was detected between the two groups at any point in time. The pooled ORs comparing the AGV implant with the Baerveldt implant were 0.51 (95 % CI: 0.33 to 0.80) for the complete success rate and 0.67 (95 % CI: 0.50 to 0.91) for qualified success rate. The Baerveldt implant was associated with a reduction in glaucoma medication at -0.51 (95 % CI: -0.90 to -0.12). There were no significant differences between the AGV implant and the Baerveldt implant on the rates of adverse events. The Baerveldt implant is more effective in both its surgical success rate and reducing glaucoma medication, but it is comparable to the AGV implant in lowering IOP. Both implants may have comparable incidences of adverse events.

  6. Flow Test to Predict Early Hypotony and Hypertensive Phase After Ahmed Glaucoma Valve (AGV) Surgical Implantation.

    Science.gov (United States)

    Cheng, Jason; Beltran-Agullo, Laura; Buys, Yvonne M; Moss, Edward B; Gonzalez, Johanna; Trope, Graham E

    2016-06-01

    To assess the validity of a preimplantation flow test to predict early hypotony [intraocular pressure (IOP)≤5 mm Hg on 2 consecutive visits and hypertensive phase (HP) (IOP>21 mm Hg) after Ahmed Glaucoma Valve (AGV) implantation. Prospective interventional study on patients receiving an AGV. A preimplantation flow test using a gravity-driven reservoir and an open manometer was performed on all AGVs. Opening pressure (OP) and closing pressure (CP) were defined as the pressure at which fluid was seen to flow or stop flowing through the AGV, respectively. OP and CP were measured twice per AGV. Patients were followed for 12 weeks. In total, 20 eyes from 19 patients were enrolled. At 12 weeks the mean IOP decreased from 29.2±9.1 to 16.8±5.2 mm Hg (P<0.01). The mean AGV OP was 17.5±5.4 mm Hg and the mean CP was 6.7±2.3 mm Hg. Early (within 2 wk postoperative) HP occurred in 37% and hypotony in 16% of cases. An 18 mm Hg cutoff for the OP gave a sensitivity of 0.71, specificity of 0.83, positive predictive value of 0.71, and negative predictive value of 0.83 for predicting an early HP. A 7 mm Hg cutoff for the CP yielded a sensitivity of 1.0, specificity of 0.38, positive predictive value of 0.23, and negative predictive value of 1.0 for predicting hypotony. Preoperative OP and CP may predict early hypotony or HP and may be used as a guide as to which AGV valves to discard before implantation surgery.

  7. Adjunctive triamcinolone acetonide for Ahmed glaucoma valve implantation: a randomized clinical trial.

    Science.gov (United States)

    Yazdani, Shahin; Doozandeh, Azadeh; Pakravan, Mohammad; Ownagh, Vahid; Yaseri, Mehdi

    2017-06-26

    To evaluate the effect of intraoperative sub-Tenon injection of triamcinolone acetonide (TA) as an adjunct to Ahmed glaucoma valve (AGV) implantation. In this triple-blind randomized clinical trial, 104 eyes with refractory glaucoma were randomly assigned to conventional AGV (non-TA group) or AGV with adjunctive triamcinolone (TA group). In the TA group, 10 mg TA was injected in the sub-Tenon space around the AGV plate intraoperatively. Patients were followed for 1 year. The main outcome measure was intraocular pressure (IOP). Other outcome measures included best-corrected visual acuity (BCVA), occurrence of hypertensive phase (HP), peak IOP, number of antiglaucoma medications, and complications. A total of 90 patients were included in the final analysis. Mean IOP was lower in the TA group at most follow-up visits; however, the difference was statistically significant only at the first month (p = 0.004). Linear mixed model showed that mean IOP was 1.5 mm Hg lower in the TA group throughout the study period (p = 0.006). Peak postoperative IOP was significantly lower in the TA group (19.3 ± 4.8 mm Hg versus 29 ± 9.2 mm Hg, p = 0.032). Rates of success (defined as 6 2 lines was more common in the non-TA group (p = 0.032). Adjunctive intraoperative TA injection during AGV implantation can blunt peak IOP levels and reduce mean IOP up to 1 year. Visual outcomes also seem to be superior to standard surgery.

  8. Comparison of the Ahmed and Baerveldt glaucoma shunts with combined cataract extraction.

    Science.gov (United States)

    Rai, Amrit S; Shoham-Hazon, Nir; Christakis, Panos G; Rai, Amandeep S; Ahmed, Iqbal Ike K

    2018-04-01

    To compare the surgical outcomes of combined phacoemulsification with either Ahmed glaucoma valve (AGV) or Baerveldt glaucoma implant (BGI). Retrospective cohort study. A total of 104 eyes that underwent combined phacoemulsification with either AGV (PhacoAGV; n = 57) or BGI (PhacoBGI; n = 47) implantation. Failure was defined as uncontrolled intraocular pressure (IOP; glaucoma surgery, vision-threatening complications, or progression to no-light-perception vision. The PhacoAGV group was older (p = 0.03), had poorer baseline visual acuity (VA; p = 0.001), and had fewer previous glaucoma surgeries (p = 0.04). Both groups had similar baseline IOP (PhacoAGV: 26.4 ± 8.3 mm Hg; PhacoBGI: 25.7 ± 7.3; p = 0.66) and glaucoma medications (PhacoAGV: 3.8 ± 1.0; PhacoBGI: 3.6 ± 1.5; p = 0.54). At 2 years, failure rates were 44% in the PhacoAGV group and 23% in the PhacoBGI group (p = 0.02). Both groups had similar mean IOP reduction (PhacoAGV: 45%; PhacoBGI: 47%, p = 0.67) and medication use reduction (PhacoAGV: 47%; PhacoBGI: 58%, p = 0.38). The PhacoBGI group had higher IOP and medication use up to 1 month (p glaucoma medications, or complication rates between PhacoAGV and PhacoBGI at 2 years, despite BGIs being implanted in patients at higher risk for failure. The PhacoAGV group had higher failure rates at 2 years. Both groups had significant improvements in VA due to removal of their cataracts. The PhacoBGI group required more interventions, but most of these were minor slit-lamp procedures. Copyright © 2018. Published by Elsevier Inc.

  9. Clinical efficacy analysis of Ahmed glaucoma valve implantation in neovascular glaucoma and influencing factors

    Science.gov (United States)

    He, Ye; Tian, Ying; Song, Weitao; Su, Ting; Jiang, Haibo; Xia, Xiaobo

    2017-01-01

    Abstract This study aimed to evaluate the efficacy of Ahmed glaucoma valve (AGV) implantation in treating neovascular glaucoma (NVG) and to analyze the factors influencing the surgical success rate. This is a retrospective review of 40 eyes of 40 NVG patients who underwent AGV implantation at Xiangya Hospital of Central South University, China, between January 2014 and December 2016. Pre- and postoperative intraocular pressure (IOP), visual acuity, surgical success rate, medications, and complications were observed. Surgical success criteria were defined as IOP ≤21 and >6 mm Hg with or without additional medications. Kaplan–Meier survival curves and Multivariate cox regression analysis were used to examine success rates and risk factors for surgical outcomes. The mean follow-up period was 8.88 ± 3.12 months (range: 3–17). IOP declined at each visit postoperatively and it was statistically significant (P < .001). An average of 3.55 ± 0.86 drugs was applied preoperatively, while an average of 0.64 ± 0.90 drugs was used postoperatively, with the difference being of statistical significance (P < .05). The complete surgical success rate of 3, 6, and 12 months after the operation was 85%, 75%, and 65%, respectively. Meanwhile, the qualified success rate of 3, 6, and 12 months after the operation was 85%, 80%, and 77.5%, respectively. The multivariate cox regression analysis showed that age (hazard ratio: 3.717, 7.246; 95% confidence interval: 1.149–12.048, 1.349–38.461; P = .028, .021) was influencing factors for complete success rate and qualified success rate among all NVG patients. Gender, previous operation history, primary disease, and preoperative IOP were found to be not significant. AGV implantation is an effective and safe surgical method to treat NVG. Age is an important factor influencing the surgical success rate. PMID:29049253

  10. Ahmed Glaucoma Valve Implantation for Uveitic Glaucoma Secondary to Behçet Disease.

    Science.gov (United States)

    Satana, Banu; Yalvac, Ilgaz S; Sungur, Gulten; Eksioglu, Umit; Basarir, Berna; Altan, Cigdem; Duman, Sunay

    2015-01-01

    To evaluate outcomes of patients with uveitic glaucoma secondary to Behçet disease (BD) who underwent Ahmed glaucoma valve (AGV) implantation. A retrospective chart review of 14 eyes of 10 patients with uveitic glaucoma associated with BD who underwent AGV implantation at a tertiary referral center. Treatment success was defined as intraocular pressure (IOP) between 6 and 21 mm Hg with or without antiglaucoma medication, without further additional glaucoma surgery or loss of light perception. The main outcome measures were IOP, best-corrected visual acuity measured with Snellen charts, and number of glaucoma medications. Mean duration of postoperative follow-up was 18.2±6.6 months (range, 6 to 31 mo). Of the 14 eyes, 10 (71.4%) were pseudophakic and 5 (35.7%) had primary AGV implantation without a history of previous glaucoma surgery. At the most recent follow-up visit, 13 of the 14 eyes had an IOP between 6 and 21 mm Hg. Mean IOP was significantly reduced during follow-up, as compared with preoperative values (P≤0.005). The cumulative probability of surgical success rate was 90.9% at 18 months based on Kaplan-Meier survival analysis. The mean number of antiglaucoma medications required to achieve the desired IOP decreased from 3.4±0.5 preoperatively to 1.0±1.1 postoperatively (P≤0.05). Visual acuity loss of >2 lines occurred in 4 eyes (28.5%) due to optic atrophy associated with retinal vasculitis. Temporary hypotony developed during follow-up in 4 eyes (28.5%) at first postoperative week. For the management of uveitic glaucoma associated with BD, AGV implantation is a successful method for glaucoma control but requires additional surgical interventions for high early hypotony rates.

  11. Clinical outcomes after combined Ahmed glaucoma valve implantation and penetrating keratoplasty or pars plana vitrectomy.

    Science.gov (United States)

    Lee, Jin Young; Sung, Kyung Rim; Tchah, Hung Won; Yoon, Young Hee; Kim, June Gone; Kim, Myoung Joon; Kim, Jae Yong; Yun, Sung-Cheol; Lee, Joo Yong

    2012-12-01

    To evaluate whether a combination of penetrating keratoplasty (PKP) or pars plana vitrectomy (PPV) and Ahmed glaucoma valve (AGV) implantation affords a level of success similar to that of AGV implantation alone. Eighteen eyes underwent simultaneous PPV and AGV, 14 eyes with PKP and AGV and 30 eyes with AGV implantation alone were evaluated. Success was defined as attainment of an intraocular pressure (IOP) >5 and glaucoma medication. Kaplan-Meier survival analysis was performed to compare cumulative survival between the combined surgery groups and the AGV implantation-alone group. Cox proportional hazard regression analysis was conducted to identify factors predictive of success in each of the three groups. Mean (±standard deviation) preoperative IOP was 30.2 ± 10.2 mmHg in the PKP + AGV, 35.2 ± 9.8 mmHg in the PPV + AGV, and 36.2 ± 10.1 mmHg in the AGV implantation-alone group. The cumulative success rate at 18 months was 66.9%, 73.2%, and 70.8% in the three groups, respectively. Neither combined surgery group differed significantly in terms of cumulative success rate compared with the AGV implantation-alone group (p = 0.556, p = 0.487, respectively). The mean number of preoperative anti-glaucoma medications prescribed was significantly associated with success in the PKP + AGV implantation group (hazard ratio, 2.942; p = 0.024). Either PKP or PPV performed in conjunction with AGV implantation afforded similar success rates compared to patients treated with AGV implantation alone. Therefore, in patients with refractory glaucoma who have underlying corneal or retinal pathology requiring treatment with PKP or PPV, AGV implantation can be performed simultaneously.

  12. Bender/Coiler for Tubing

    Science.gov (United States)

    Stoltzfus, J. M.

    1983-01-01

    Easy-to-use tool makes coils of tubing. Tubing to be bend clamped with stop post. Die positioned snugly against tubing. Operator turns handle to slide die along tubing, pushing tubing into spiral groove on mandrel.

  13. High aspect ratio catalytic reactor and catalyst inserts therefor

    Science.gov (United States)

    Lin, Jiefeng; Kelly, Sean M.

    2018-04-10

    The present invention relates to high efficient tubular catalytic steam reforming reactor configured from about 0.2 inch to about 2 inch inside diameter high temperature metal alloy tube or pipe and loaded with a plurality of rolled catalyst inserts comprising metallic monoliths. The catalyst insert substrate is formed from a single metal foil without a central supporting structure in the form of a spiral monolith. The single metal foil is treated to have 3-dimensional surface features that provide mechanical support and establish open gas channels between each of the rolled layers. This unique geometry accelerates gas mixing and heat transfer and provides a high catalytic active surface area. The small diameter, high aspect ratio tubular catalytic steam reforming reactors loaded with rolled catalyst inserts can be arranged in a multi-pass non-vertical parallel configuration thermally coupled with a heat source to carry out steam reforming of hydrocarbon-containing feeds. The rolled catalyst inserts are self-supported on the reactor wall and enable efficient heat transfer from the reactor wall to the reactor interior, and lower pressure drop than known particulate catalysts. The heat source can be oxygen transport membrane reactors.

  14. The first LHC insertion quadrupole

    CERN Multimedia

    2004-01-01

    An important milestone was reached in December 2003 at the CERN Magnet Assembly Facility. The team from the Accelerator Technology - Magnet and Electrical Systems group, AT-MEL, completed the first special superconducting quadrupole for the LHC insertions which house the experiments and major collider systems. The magnet is 8 metres long and contains two matching quadrupole magnets and an orbit corrector, a dipole magnet, used to correct errors in quadrupole alignment. All were tested in liquid helium and reached the ultimate performance criteria required for the LHC. After insertion in the cryostat, the superconducting magnet will be installed as the Q9 quadrupole in sector 7-8, the first sector of the LHC to be put in place in 2004. Members of the quadrupole team, from the AT-MEL group, gathered around the Q9 quadrupole at its inauguration on 12 December 2003 in building 181.

  15. Insertion device calculations with mathematica

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R. [Stanford Synchrotron Radiation Lab., CA (United States); Lidia, S. [Univ. of California, Davis, CA (United States)

    1995-02-01

    The design of accelerator insertion devices such as wigglers and undulators has usually been aided by numerical modeling on digital computers, using code in high level languages like Fortran. In the present era, there are higher level programming environments like IDL{reg_sign}, MatLab{reg_sign}, and Mathematica{reg_sign} in which these calculations may be performed by writing much less code, and in which standard mathematical techniques are very easily used. The authors present a suite of standard insertion device modeling routines in Mathematica to illustrate the new techniques. These routines include a simple way to generate magnetic fields using blocks of CSEM materials, trajectory solutions from the Lorentz force equations for given magnetic fields, Bessel function calculations of radiation for wigglers and undulators and general radiation calculations for undulators.

  16. Ring insertions as light sources

    International Nuclear Information System (INIS)

    Green, G.K.

    1975-01-01

    Bending magnets can be inserted in the long straight sections of electron storage rings to produce synchrotron radiation. If the design is carefully proportioned, the bending magnets create only a small perturbation of the properties of the ring. The resulting spectra have favorable optical properties as sources for spectroscopy and diffraction studies. The characteristics of the source are discussed, and the geometrical requirements of the magnets are presented

  17. Inserts for nuclear fuel elements

    International Nuclear Information System (INIS)

    Cragg, P.J.

    1982-01-01

    An insert for a nuclear fuel pin which comprises a strip. The strip carries notches, which enable a coding arrangement to be carried on the strip. The notches may be of differing sizes and the coding on the strip includes identification and identification checking data. Each notch on the strip may give rise to a signal pulse which is counted by a detector to avoid errors. (author)

  18. ATLAS insertable B-layer

    Czech Academy of Sciences Publication Activity Database

    Marčišovský, Michal

    2011-01-01

    Roč. 633, č. 1 (2011), "S224"-"S225" ISSN 0168-9002. [International workshop on radiation imaging detectors /11./. Praha, 26.06.2009-02.07.2009] R&D Projects: GA MŠk LA08015; GA MŠk LA08032 Institutional research plan: CEZ:AV0Z10100502 Keywords : ATLAS * pixel detector * insertable B-layer Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.207, year: 2011

  19. HTS Insert Magnet Design Study

    CERN Document Server

    Devaux, M; Fleiter, J; Fazilleau, P; Lécrevisse, T; Pes, C; Rey, J-M; Rifflet, J-M; Sorbi, M; Stenvall, A; Tixador, P; Volpini, G

    2011-01-01

    Future accelerator magnets will need to reach higher field in the range of 20 T. This field level is very difficult to reach using only Low Temperature Superconductor materials whereas High Temperature Superconductors (HTS) provide interesting opportunities. High current densities and stress levels are needed to design such magnets. YBCO superconductor indeed carries large current densities under high magnetic field and provides good mechanical properties especially when produced using the IBAD approach. The HFM EUCARD program studies the design and the realization of an HTS insert of 6 T inside a Nb$_{3}$Sn dipole of 13T at 4.2 K. In the2HTS insert, engineering current densities higher than 250 MA/m under 19 T are required to fulfill the specifications. The stress level is also very severe. YBCO IBAD tapes theoretically meet these challenges from presented measurements. The insert protection is also a critical because HTS materials show low quench propagation velocities and the coupling with the Nb$_{3}$Sn m...

  20. Prof.Dr. Ahmed Yüksel Özemre’nin Tasavvufî Görüşleri

    OpenAIRE

    KALKAN, Bilgihan

    2015-01-01

    Prof. Dr. Ahmed Yüksel Özemre(1935-2008), Türkiye’nin ilk atom mühendisiolmasının yanı sıra Türkiye Atom Enerjisi (TAE) Kurumundaki görevidolayısı ile ülkemizin tanınmış ilim adamlarındandır. Bu makalede Prof. Dr. AhmedYüksel Özemre’nin daha az bilinen ve çocukluk çağlarında tasavvufî muhitlerile yakın temas halinde bulunması ile başlayan ve zaman içerisinde yalnızcaentelektüel bir uğraş olmanın ötesine geçerek, yaşam şekline dönüşen tasavvufîhayatı ve genel hatları ile İslâm tasavvufu hakkın...

  1. Outcome of Descemet stripping automated endothelial keratoplasty in eyes with an Ahmed glaucoma valve.

    Science.gov (United States)

    Chiam, Patrick J; Cheeseman, Robert; Ho, Vivian W; Romano, Vito; Choudhary, Anshoo; Batterbury, Mark; Kaye, Stephen B; Willoughby, Colin E

    2017-05-01

    The purpose was to investigate the survival of Descemet stripping automated endothelial keratoplasty (DSAEK) in eyes with an Ahmed glaucoma valve (AGV). The study had a retrospective case-series of patients with an AGV in the anterior chamber undergoing a DSAEK. Included in the analysis were graft size, number of previous operations, post-operative glaucoma medications, post-operative intraocular pressure (IOP) control, graft size and donor factors (age, endothelial cell density, and post-mortem time). A generalised linear model with binary logistic regression was used to test for an effect on graft survival at 1 year and 1.5 years. Fourteen eyes from 13 patients were included. The survival rate of the first DSAEK at 6, 12, 18, 24 and 30-months was 85%, 71%, 50%, 36% and 30%, respectively. The mean duration to graft failure was 12.9 ± 6.2 months. Five of the seven failed first grafts went on to have a repeat DSAEK. The mean follow-up in this subgroup was 30.7 ± 18.4 months. The survival rate of second DSAEK at 6, 12, 18 and 24 months was 100% (5/5), 100% (5/5), 75% (3/4) and 67% (2/3). Only one second DSAEK failed in the duration of the study and went on to receive a third DSAEK which failed at 18-months. The mean IOP within the first year was significantly lower for grafts that survived at 1 and 1.5 years (17.4 mmHg, 16.9 mmHg) than for grafts that failed (19.4 mmHg, 19.4 mmHg) (p = 0.04, p = 0.009). DSAEK is a viable alternative to PK to restore visual function in eyes with an AGV sited in the anterior chamber. IOP is an important risk factor for graft failure.

  2. Five-year Treatment Outcomes in the Ahmed Baerveldt Comparison Study

    Science.gov (United States)

    Budenz, Donald L.; Barton, Keith; Gedde, Steven J.; Feuer, William J.; Schiffman, Joyce; Costa, Vital P.; Godfrey, David G.; Buys, Yvonne M.

    2014-01-01

    Purpose To compare the five year outcomes of the Ahmed FP7 Glaucoma Valve (AGV) and the Baerveldt 101-350 Glaucoma Implant (BGI) for the treatment of refractory glaucoma. Design Multicenter randomized controlled clinical trial. Participants 276 patients, including 143 in the AGV group and 133 in the BGI group. Methods Patients 18 to 85 years of age with previous intraocular surgery or refractory glaucoma and intraocular pressure (IOP) of ≥ 18 mmHg in whom glaucoma drainage implant surgery was planned were randomized to implantation of either an AGV or BGI. Main Outcome Measures IOP, visual acuity, use of glaucoma medications, complications, and failure (IOP > 21 mmHg or not reduced by 20% from baseline, IOP ≤ 5 mmHg, reoperation for glaucoma, removal of implant, or loss of light perception). Results At 5 years, IOP (mean ± SD) was 14.7 ± 4.4 mmHg in the AGV group and 12.7 ± 4.5 mmHg in the BGI group (p = 0.012). The number of glaucoma medications in use at 5 years (mean ± SD) was 2.2 ± 1.4 in the AGV group and 1.8 ± 1.5 in the BGI group (p = 0.28). The cumulative probability of failure during 5 years of follow-up was 44.7% in the AGV group and 39.4% in the BGI group (p = 0.65). The number of subjects failing due to inadequately controlled IOP or reoperation for glaucoma was 46 in the AGV group (80% of AGV failures) and 25 in the BGI group (53% of BGI failures, p=0.003). Eleven AGV eyes (20% of AGV failures) experienced persistent hypotony, explantation of implant, or loss of light perception compared to 22 (47% of failures) in the BGI group. The 5-year cumulative reoperation rate for glaucoma was 20.8% in the AGV group compared to 8.6% in the BGI group (p=0.010). Change in logMAR Snellen visual acuity (mean ± SD) at 5 years was 0.42 ± 0.99 in the AGV group and 0.43 ± 0.84 in the BGI group (p=0.97). Conclusions Similar rates of surgical success were observed with both implants at 5 years. BGI implantation produced greater IOP reduction and a lower rate

  3. Comparison of 1-year outcomes after Ahmed glaucoma valve implantation with and without Ologen adjuvant.

    Science.gov (United States)

    Kim, Tai Jun; Kang, Sohyun; Jeoung, Jin Wook; Kim, Young Kook; Park, Ki Ho

    2018-02-14

    Many studies have investigated the clinical benefits of Ologen for trabeculectomy. However, its benefits for Ahmed glaucoma valve (AGV) implantation have not been investigated as extensively. The aim of this study was to compare the 1-year outcomes of AGV implantation with and without Ologen adjuvant for the treatment of refractory glaucoma. This retrospective study included a total of 20 eyes of 20 glaucoma patients, who were followed for at least 1-year after undergoing AGV implantation. In 12 eyes of 12 patients, conventional AGV (CAGV) surgery was performed, while in 8 eyes of 8 patients, Ologen-augmented AGV (OAGV) implantation was performed. The outcomes were evaluated according to intraocular pressure (IOP) and the number of IOP-lowering medications. Complete success was defined as IOP ≤ 21 mmHg without medications throughout the 1-year follow-up period, and qualified success was defined as IOP ≤ 21 mmHg with or without medications throughout the 1-year follow-up period. The rate of complete success was significantly higher in the OAGV group (50.0%) than in the CAGV group (8.3%) (p = 0.035). There were no significant differences between the two groups in terms of qualified success or incidence of the early hypertensive phase. The IOP changes were similar between the groups within 1-year postoperatively, though the number of IOP-lowering medications was significantly lower in the OAGV group during the early hypertensive phase (p = 0.031, 0.031, and 0.025 at postoperative months 1, 2, and 3, respectively). When subjects were divided into groups according to the occurrence of the early hypertensive phase, the group with early hypertensive phase was more likely to use IOP-lowering medications at postoperative 6 months and 1 year (p = 0.002 and 0.005, respectively). OAGV surgery shows encouraging results for patients with refractory glaucoma, specifically with respect to the achievement of complete success and the reduction of the

  4. Treatment Outcomes in the Ahmed Baerveldt Comparison Study after One Year of Follow-up

    Science.gov (United States)

    Budenz, Donald L; Barton, Keith; Feuer, William J; Schiffman, Joyce; Costa, Vital P.; Godfrey, David G.; Buys, Yvonne

    2010-01-01

    Purpose To determine the relative efficacy and complications of the Ahmed FP7 Glaucoma Valve (AGV) and the Baerveldt 101–350 Glaucoma Implant (BGI) in refractory glaucoma. Design Multicenter randomized controlled clinical trial. Participants 276 patients, including 143 in the AGV group and 133 in the BGI group. Methods Patients aged 18–85 years with refractory glaucoma with intraocular pressure (IOP) greater than or equal to 18 mm Hg in whom an aqueous shunt was planned were randomized to undergo implantation of either an AGV or a BGI. Main Outcome Measures Primary outcome was failure, defined as IOP > 21 mm Hg or not reduced by 20%, IOP ≤ 5 mm Hg, reoperation for glaucoma or removal of implant, or loss of light perception vision. Secondary outcomes included mean IOP, visual acuity, use of supplemental medical therapy, and complications. Results Preoperative IOP (mean ± standard deviation, SD) was 31.2 ± 11.2 in the AGV group and 31.8 ± 12.5 in the BGI group (p = 0.71). At 1 year, IOP was 15.4 ± 5.5 mm Hg in the AGV group and 13.2 ± 6.8 mm Hg in the BGI group (p = 0.007). The number of glaucoma medications (mean ± SD) was 1.8 ± 1.3 in the AGV group and 1.5 ± 1.4 in the BGI group (p = 0.071). The cumulative probability of failure was 16.4% (standard error, SE = 3.1%) in the AGV group and 14.0% (SE = 3.1%) in the BGI group at 1 year (p = 0.52). More patients experienced early postoperative complications in the BGI group (n = 77, 58%) compared to the AGV group (n = 61, 43%, p = 0.016). Serious postoperative complications associated with reoperation and/or vision loss of ≥ 2 Snellen lines occurred in 29 patients (20%) in the AGV group and 45 patients (34%) in the BGI group (p = 0.014). Conclusions Although the average IOP after one year was slightly higher in patients who received an AGV, there were fewer early and serious postoperative complications associated with the use of the AGV than the BGI. PMID:20932583

  5. Three-year Treatment Outcomes in the Ahmed Baerveldt Comparison Study

    Science.gov (United States)

    Barton, Keith; Feuer, William J; Budenz, Donald L; Schiffman, Joyce; Costa, Vital P.; Godfrey, David G.; Buys, Yvonne M.

    2014-01-01

    Purpose To compare three year outcomes and complications of the Ahmed FP7 Glaucoma Valve (AGV) and Baerveldt 101–350 Glaucoma Implant (BGI) for the treatment of refractory glaucoma. Design Multicenter randomized controlled clinical trial. Participants 276 patients; 143 in the AGV group and 133 in the BGI group. Methods Patients aged 18–85 years with refractory glaucoma and intraocular pressures (IOPs) ≥18 mmHg in whom an aqueous shunt was planned were randomized to either an AGV or a BGI. Main Outcome Measures IOP, visual acuity, supplemental medical therapy, complications, and failure (IOP > 21 mmHg or not reduced by 20% from baseline, IOP ≤ 5 mmHg, reoperation for glaucoma or removal of implant, or loss of light perception vision). Results At 3 years, IOP (mean ± standard deviation) (SD) was 14.3 ± 4.7 mmHg (AGV group) and 13.1 ± 4.5 mmHg (BGI group) (p = 0.086) on 2.0 ± 1.4 and 1.5 ± 1.4 glaucoma medications respectively (p = 0.020). The cumulative probabilities of failure were 31.3% (standard error = 4.0%) (SE) (AGV) and 32.3% (4.2%) (BGI) (p = 0.99). Postoperative complications associated with reoperation or vision loss of ≥ 2 Snellen lines occurred in 24 patients (22%) (AGV) and 38 patients (36%) (BGI) (p = 0.035). The mean change in the Logarithm of the Minimum Angle of Resolution visual acuity (logMAR VA) at 3 years was similar (AGV: 0.21 ± 0.88, BGI: 0.26 ± 0.74) in the two treatment groups at 3 years (p=0.66). The cumulative proportion of patients (SE) undergoing reoperation for glaucoma prior to the three year postoperative time point was 14.5% (3.0%) in the AGV group compared to 7.6% (2.4%) in the BGI group (p=0.053, log-rank). The relative risk of reoperation for glaucoma in the AGV group was 2.1 times that of the BGI group (95% Confidence Interval:1.0–4.8, p=0.045; Cox proportional hazards regression). Conclusions AGV implantation was associated with the need for significantly greater adjunctive medication to achieve equal success

  6. Comparison of the Ahmed glaucoma valve with the Baerveldt glaucoma implant: a meta-analysis.

    Science.gov (United States)

    Wang, Yi-Wen; Wang, Ping-Bao; Zeng, Chao; Xia, Xiao-Bo

    2015-10-13

    This study aims to compare the efficacy and safety of the Ahmed glaucoma valve (AGV) with the Baerveldt glaucoma implant (BGI) in glaucoma patients. Databases were searched to identify studies that met pre-stated inclusion criteria, involving randomized controlled clinical trials (RCTs) and non-randomized controlled clinical trials. Treatment effect was analyzed using a random-effect model. Ten controlled clinical trials (1048 eyes) were analyzed, involving two RCTs and eight retrospective comparative studies. Short-term results (6-18 months) and long-term results (>18 months) were analyzed separately. There was no significant difference in the success rate for short-term follow-up between the AGV and BGI groups (5 studies, 714 eyes, odds ratio [OR]: 0.97; 95 % confidence interval [CI]: 0.56, 1.66; P = 0.90). For long-term pooled results (7 studies, 835 eyes), the success rate of AGVs was lower than that of BGIs (OR: 0.73; 95 % CI: 0.54, 0.99, P = 0.04), However, subgroup and sensitivity analyses did not show a significant difference in the success rate between the two groups (P ≥0.05). The AGV group had a higher mean intraocular pressure than the BGI group in short-term (6 studies, 685 eyes, weighted mean difference [WMD]: 2.12 mmHg; 95 % CI: 0.72-3.52; P glaucoma medications after implantation than the AGV group in two follow-up periods (all P <0.05). The AGV was found to be associated with a significantly lower frequency of total complications (8 studies, 971 eyes, OR: 0.67; 95 % CI: 0.50-0.90; P = 0.007) and severe complications (8 studies, 971 eyes, OR: 0.57; 95 % CI: 0.36-0.91; P = 0.02) than the BGI. The study showed no significant difference in success rate between the two groups. The BGI was more effective for control of intraocular pressure and required fewer medications than the AGV, but the AGV had lower incidence of total and severe complications than the BGI.

  7. Mitomycin-C Trabeculectomy versus Ahmed Glaucoma Implant in Pediatric Aphakic Glaucoma

    Directory of Open Access Journals (Sweden)

    Mohammad Pakravan

    2008-12-01

    Full Text Available

    PURPOSE: To compare the outcomes and complications of mitomycin-C trabeculectomy (MMC-T versus the Ahmed glaucoma implant (AGI for treatment of pediatric aphakic glaucoma. METHODS: In a randomized clinical trial, 30 eyes of 28 children < 16 years of age who had undergone anterior lensectomy-vitrectomy for congenital cataract were assigned to MMC-T (15 eyes of 13 children or AGI (15 eyes of 15 children. Surgical success was classified as complete (IOP 6-21 mmHg without any antiglaucoma medication and partial (IOP 6-21 mmHg with < 2 topical antiglaucoma agents in the absence of any sight-threatening complication or need for further glaucoma surgery, stable cup/disc ratios and visual loss < 2 Snellen lines. Overall success was defined as the sum of complete and partial success. RESULTS: Mean patient age was 9.1±4.1 and 10.9±5.1 years in the MMC-T and AGI groups, respectively (P=0.29. After a mean follow up of 14.8±11 and 13.1±9.7 months; complete, partial and overall success rates were 33.3%, 40% and 73.3% in the MMC-T vs 20%, 66.7% and 86.7% in the AGI groups, respectively (P= 0.361. Complication and failure rates were 40% and 26.7% in the MMC-T group vs 26.7% and 13.3% in the AGI group, respectively (P= 0.439. CONCLUSION: MMC-T and AGI seem to be comparable in terms of success and complications as the initial surgical

  8. Incidence of nutritional anaemia among the under five children attending Ahmed Gasim hospital

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Hager Elrasheed Ali [Home Science Department, Faculty of Education, University of Khartoum, Khartoum (Sudan)

    1998-11-01

    A survey was carried out in Khartoum North Ahmed Gasim specialist Hospital for children to identify aetiological factors that lead to incidence of nutritional anaemia among children under under five years of age. The sample consists of 192 patients taken from the hospital wards (experimental group), and 60 healthy children taken from out patient vaccination department of same hospital. A questionnaire was used as a tool for collection data regarding children and their families with emphasis to general information, socio-economic information, dietary information, anthropometric information, medical history and laboratory investigations including haemoglobin, hematocrit (PCV)%, peripheral blood picture, serum ferritin, serum folate and serum B{sup 12}. Results show no correlation between anaemia and age R(0.1048) p<0.148 and there was no significant difference between anaemia and sex p<(0.104). There is a high significant difference between control and experimental group for Hb and PCV (p<0.00). Aetiological factors related to nutritional anaemia are: poor intake as a supplement or weaning food was poor in iron and folate content. Weaning is sudden because of pregnancy, insufficient milk, mother or child illness and also other causes: low income and many mouths to feed, crowded and unhealthy living conditions, some families had latrines in their houses while others hadn`t. Drinking water is brought from a far distance. The most prevailing type of anaemia is iron deficiency about 26% followed by megaloblastic (10.69%). Which is due to folate deficiency (6.41%), folate and B{sup 1}2 deficiency. Some children affected had mixed deficiency anaemia (3.182). Iron deficiency without anaemia was common among healthy children (control) 22.8%. Some recommendations were set for the improvement of the existing situation e.g. health education, nutrition education with emphasis on intake of supplements and weaning diets rich in iron and folate. Follow up and surveillance program

  9. Device for facilitating the insertion and withdrawal of fuel assemblies from a nuclear reactor

    International Nuclear Information System (INIS)

    Andrea, C.; Siegel, E.A.

    1976-01-01

    A device is provided which is installed in a reactor prior to carrying out refueling operations and which accurately locates and isolates a selected core location to permit rapid withdrawal and insertion of fuel subassemblies at that location. A shielded plug designed to cooperate with the refueling apparatus is inserted into an access port in the reactor head. A structural shroud extends down from the plug and carries at its lower end a radially floating, hexagonal spreader tube with mechanisms to rotate it for angular alignment purposes and a linear drive for inserting it into the core. The upper end of the spreader tube serves as a guide for leading the fuel handling apparatus into alignment with the chosen subassembly

  10. Pressure vessels and methods of sealing leaky tubes disposed in pressure vessels

    International Nuclear Information System (INIS)

    Larson, G.C.

    1980-01-01

    This invention relates to pressure vessels and to methods of sealing leaky tubes in them and is especially applicable to pressure vessels in the form of sheet-and-tube type heat exchangers constructed with a large number of relatively small diameter tubes grouped in a bundle. To seal off a leaky tube in such a heat exchanger an explosive activated plug in the form of a hollow metal body is used, inserted at each end of the tube to be sealed. Using the arrangement of pressure vessel and associated tube sheets and the explosive activated plug method of sealing a leaky tube as described in this invention it is claimed that distortion of the adjacent tubes and the tube sheets is reduced when the explosive activated plugs are detonated. (U.K.)

  11. Difficulty with cuff deflation of reinforced tracheal tube caused by inflation line occlusion with silk thread ligation and fixation.

    Science.gov (United States)

    Gotoh, Sayoko; Sugiyama, Daisuke; Imai, Eriko; Kawamata, Mikito

    2015-03-05

    A reinforced tracheal tube, ligated with silk threads, was inserted into a tracheostomy orifice and fixed to the skin. The cuff inflation line of the reinforced tracheal tube became occluded. Reinforced 'armoured' tracheal tubes have a spiral of wire embedded into the wall of the tube to give strength and flexibility, and may be sharply bent without compromising the tube lumen. The tracheal cuff attached to the tube is inflated by injecting air through a narrow-diameter tube welded to the outside of the tracheal tube. When a reinforced tracheal tube is ligated and fixed with silk threads, it should be confirmed whether the tracheal tube cuff can be deflated and inflated after fixation. Moreover, because occlusion can be eliminated by removing all silk threads used to ligate a tracheal tube, they should be removed before extubation. 2015 BMJ Publishing Group Ltd.

  12. Comparative study of the safety and efficacy of the Ahmed glaucoma valve model M4 (high density porous polyethylene) and the model S2 (polypropylene) in patients with neovascular glaucoma.

    Science.gov (United States)

    Gil-Carrasco, F; Jiménez-Román, J; Turati-Acosta, M; Bello-López Portillo, H; Isida-Llerandi, C G

    2016-09-01

    To prospectively evaluate the safety and efficacy of the Ahmed glaucoma valve model M4 (High density porous polyethylene plate; Medpor) compared with the model S2 (polypropylene plate). Mexican patients with neovascular glaucoma were randomly included for each group (M4 and S2). They were operated on using conventional techniques and creating a sub-episcleral tunnel to place the valve tube in the anterior chamber. After one year of follow-up, the results were evaluated with respect to a post-operative reduction in pressure, changes in visual acuity, the need for drugs, and complications, as well as the demographic characteristics of each group. Each operation using the M4 valve was performed by a single surgeon (FGC). Those operated on using the S2 model had their surgery performed by the staff surgeons at the Glaucoma Department of the Mexican Association to Prevent Blindness (APEC). Each group (M4 and S2) contained 21 eyes of 21 Mexican patients with a diagnosis of neovascular glaucoma, leading to a total of 42 patients undergoing surgery. The mean preoperative intraocular pressure (IOP) was 43.5 (±11.8), and 42.24 (±12.84) mmHg for the M4 and S2 groups, respectively. After one year of follow-up, the IOP reported was 18.9 (±9.7) mmHg for the final 18 patients in the M4 group, and 16.38 (±9.76) mmHg for the 21 patients in the S2 group. The design of a drainage valve device such as that of Ahmed has characteristics such as moderate control of IOP, thanks to the valve component in the immediate post-operative period, which makes them safer than other non-valve devices. This avoids an excess of flat chambers and the presence of low IOPs, which can lead to bleeding in the early post-operative period due to the weak desmosomal junctions of the newly formed vessels, with the advantage of maintaining suitable control of IOP from the first day after surgery. Further studies with longer follow-up with a larger number of patients are needed to evaluate the effectiveness

  13. Field errors in hybrid insertion devices

    International Nuclear Information System (INIS)

    Schlueter, R.D.

    1995-02-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed

  14. Field errors in hybrid insertion devices

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, R.D. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed.

  15. Visual beam tube inspection at the TRIGA reactor Vienna

    International Nuclear Information System (INIS)

    Boeck, H.; Musilek, A.; Villa, M.

    2006-01-01

    Of the four TRIGA beam tubes two have been visually inspected in 1985. Prior to the inspection the reactor was shut down for 3 weeks. The fuel elements around the beam tubes were removed. Stainless steel dummy elements were inserted in the fuel positions to shield the core radiation. The active part of the Fast Rabbit Tube was removed into the beam tube loading device and transferred to an interim storage: Front dose rate was ∼ 50 mSv/h. Generally the beam tube was very clean, after the last inspection about 30 years ago. A1 cm cut was observed at the beam tube front end. A rigid endoscope was used to check the beam tube's inner surface using a 90 degree deflection objective and photo- and video equipment. The direct dose rate in front of the beam tube was about 30 mSv/h. The beam tube was vacuum cleaned. A corroded shielding tank containing boric acid has leaked. A wooden collimator partially disintegrating due to extreme temperature was removed from beam tube D. Documentation of the inspection for visible defects is produced for later comparison

  16. Comparison of polypropylene and silicone Ahmed® glaucoma valves in the treatment of neovascular glaucoma: A 2-year follow-up.

    Science.gov (United States)

    Lubiński, Wojciech; Krzystolik, Karol; Gosławski, Wojciech; Kuprjanowicz, Leszek; Mularczyk, Maciej

    2018-01-01

    Inflammation associated with biomaterials of Ahmed® glaucoma drainage devices may cause the formation of a capsule around the device and can thus have a significant influence on the level of intraocular pressure reduction. The objective of this study was to compare the clinical outcomes after the implantation of a polypropylene or silicone Ahmed® glaucoma valve in patients with neovascular glaucoma. In the study, 27 eyes with neovascular glaucoma (group 1) received silicon Ahmed® valves and 23 eyes (group 2) received polypropylene valves. The best corrected distance visual acuity (BCDVA), intraocular pressure (IOP) and number of anti-glaucomatous drugs were recorded preoperatively and during a follow-up period of 24 months after surgery. Success was defined by the following criteria: 1) intraocular pressure in the rage of 6-21 mm Hg; 2) IOP reduction of at least 30% relative to preoperative values. All complications were registered. One month postoperatively, the mean BCDVA increased significantly in both groups compared to preoperative values (p glaucoma, the implantation of a silicone valve is associated with a significantly higher probability of long-term reduction of IOP below 21 mm Hg and with a lower risk of valve encapsulation in comparison to polypropylene valves. The obtained results suggest that silicone Ahmed® valves are more effective in the treatment of patients with neovascular glaucoma.

  17. X-ray tubes

    International Nuclear Information System (INIS)

    Young, R.W.

    1979-01-01

    A form of x-ray tube is described which provides satisfactory focussing of the electron beam when the beam extends for several feet from gun to target. Such a tube can be used for computerised tomographic scanning. (UK)

  18. Pressure tube type reactors

    International Nuclear Information System (INIS)

    Komada, Masaoki.

    1981-01-01

    Purpose: To increase the safety of pressure tube type reactors by providing an additional ECCS system to an ordinary ECCS system and injecting heavy water in the reactor core tank into pressure tubes upon fractures of the tubes. Constitution: Upon fractures of pressure tubes, reduction of the pressure in the fractured tubes to the atmospheric pressure in confirmed and the electromagnetic valve is operated to completely isolate the pressure tubes from the fractured portion. Then, the heavy water in the reactor core tank flows into and spontaneously recycles through the pressure tubes to cool the fuels in the tube to prevent their meltdown. By additionally providing the separate ECCS system to the ordinary ECCS system, fuels can be cooled upon loss of coolant accidents to improve the safety of the reactors. (Moriyama, K.)

  19. Gastrostomy feeding tube - bolus

    Science.gov (United States)

    Feeding - gastrostomy tube - bolus; G-tube - bolus; Gastrostomy button - bolus; Bard Button - bolus; MIC-KEY - bolus ... KEY, 3 to 8 weeks after surgery. These feedings will help your child grow strong and healthy. ...

  20. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...

  1. Regional insertion: an emergent approach

    International Nuclear Information System (INIS)

    Serra, M.T.F.; Nascimento Teixeira, P. do

    1989-01-01

    The Brazilian Electrical Sector incorporates new variables that expressing the extensive spectrum of environmental impacts in the take of decisions, referring to the viability of realizing a electrical undertaking, attends the several restrictions that are important by the sector and by the society in the environment area and promotes the adequate generation of liquid benefits, consequential of the electrical undertaking. Due to these factors, the Electrical Sector is improving the concept of regional insertion, with the sectorial expansion in long-dated and the created demand in the environmental and social area, focalizing the solution for these questions. (C.G.C.). 1 fig, 2 tabs

  2. Recent advances in insertion devices

    International Nuclear Information System (INIS)

    Gluskin, E.; Moog, E.R.

    1995-01-01

    Demand for more and better insertion devices (IDs) at new third-generation synchrotron radiation facilities has led to significant advances in ID technology at different laboratories around the world. In this overview of this progress, focus is on those results that apply to IDs in general rather than one specific ID or laboratory. The advances fall into two general categories: those that reduce the net effect that the ID has on the particle beam, and those that enhance the quality of the emitted light spectrum. The need for these advances, factors that are most important inaachieving them, and the current state of the art are discussed

  3. Summary of experimental insertions workshop

    International Nuclear Information System (INIS)

    Sandweiss, J.; Month, M.

    1976-01-01

    The last ISABELLE workshop of the summer 1976 series, which was held at Brookhaven, August 16-20, focused on the design and utilization of the experimental insertions. The goals of the workshop, which were somewhat more general than might be suggested by the title, are: (1) review the ISABELLE proposal from the point of view of experimental use; (2) contribute useful information on the ''open questions'' in the ISABELLE design; (3) develop data for experimental equipment and operating cost estimates; and (4) project a first approximation to ISABELLE operating modes

  4. Insertion and crossing region design

    International Nuclear Information System (INIS)

    Wienands, U.; Beloshitsky, P.

    2001-01-01

    This article is the summary of the 5-afternoon tutorial on insertions for circular machines. Roughly half the course (Part 1) was spent discussing interaction regions, We start by recapitulating basic beam optics including building blocks. This provides the tools to analyze the basic structure of interaction regions and explore the parameter space. This simple example is then successively refined and made more realistic. Examples of realized interaction regions for both hadron and electron machines are shown and their salient features and differences explained. A brief discussion of solenoid-decoupling brings Part 1 to a close. In Part 2 we discussed various utility sections. Dispersion suppressors are presented in detail discussing the principles as well as the practical implementation of flexible suppressors using LEP as an example. Injection schemes, both single-turn and multi-turn stacking, are presented in depth. The matching of wiggler and undulator insertions and a discussion of the impact of these devices on beam parameters closes out Part 2

  5. Intravesical knotting of feeding tube used as urinary catheter in an infant

    Directory of Open Access Journals (Sweden)

    Mamatha Basavaraju

    2016-09-01

    Full Text Available Infant feeding tube is commonly used to temporarily drain the bladder in pediatric population. A case is described where the tube got knotted inside the bladder probably due to over insertion or bladder spasm caused by irritation of catheter.

  6. Ahmed glaucoma valve in uveitic patients with fluocinolone acetonide implant-induced glaucoma: 3-year follow-up

    Directory of Open Access Journals (Sweden)

    Kubaisi B

    2018-05-01

    Full Text Available Buraa Kubaisi,1,2 Arash Maleki,1,2 Aseef Ahmed,1,2 Neel Lamba,1,2 Haitham Sahawneh,1,2 Andrew Stephenson,1,2 Alyssa Montieth,1,2 Shobha Topgi,3 C Stephen Foster1,2,4 1Massachusetts Eye Research and Surgery Institution, Waltham, MA, USA; 2Ocular Immunology & Uveitis Foundation, Waltham, MA, USA; 3The State University of New York Downstate, Brooklyn, NY, USA; 4Harvard Medical School, Boston, MA, USA Purpose: To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV in eyes with noninfectious uveitis that had fluocinolone acetonide intravitreal implant (Retisert™-induced glaucoma. Methods: This retrospective study reviewed the safety and efficacy of AGV implantation in patients with persistently elevated intraocular pressure (IOP after implantation of a fluocinolone acetonide intravitreal implant at the Massachusetts Eye Research and Surgery Institution between August 2006 and November 2015. Results: Nine patients with 10 uveitic eyes were included in this study, none of which had preexisting glaucoma in the study eye. Mean patient age was 42 years; 6 patients were female and 3 were male. Baseline mean IOP was 30.6 mmHg prior to AGV placement while mean IOP-lowering medications were 2.9. In the treatment groups, there was a statistically significant reduction in post-AGV IOP. IOP was lowest at 1-week after AGV implantation (9.0 mmHg. Nine out of 10 eyes achieved an IOP below target value of 22 mmHg and/or a 20% reduction in IOP from baseline 1 month and 1 year following AGV placement. All other postoperative time points showed all 10 eyes reaching this goal. A statistically significant decrease in IOP-lowering medication was seen at the 1-week, 1-month, and 3-year time points compared to baseline, while a statistically significant increase was seen at the 3-month, 6-month, and 2-year post-AGV time points. No significant change in retinal nerve thickness or visual field analysis was found. Conclusion: AGV is an effective and safe method of

  7. 21 CFR 868.5800 - Tracheostomy tube and tube cuff.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tracheostomy tube and tube cuff. 868.5800 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5800 Tracheostomy tube and tube cuff. (a) Identification. A tracheostomy tube and tube cuff is a device intended to be placed into a...

  8. Risk factors for tube exposure as a late complication of glaucoma drainage implant surgery

    Directory of Open Access Journals (Sweden)

    Chaku M

    2016-03-01

    Full Text Available Meenakshi Chaku,1 Peter A Netland,2 Kyoko Ishida,3 Douglas J Rhee4 1Department of Ophthalmology, Loyola University Chicago, Maywood, IL, 2Department of Ophthalmology, University of Virginia School of Medicine, Charlottesville, VA, USA; 3Department of Ophthalmology, Toho University, Tokyo, Japan; 4Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH, USA Purpose: The purpose of this study was to evaluate the risk factors for tube exposure after glaucoma drainage implant surgery.Patients and methods: This was a retrospective case-controlled observational study of 64 eyes from 64 patients. Thirty-two eyes of 32 patients with tube erosion requiring surgical revision were compared with 32 matched control eyes of 32 patients. Univariate and multivariate risk factor analyses were performed.Results: Mean age was significantly younger in the tube exposure group compared with the control group (48.2±28.1 years versus 67.3±18.0 years, respectively; P=0.003. The proportion of diabetic patients (12.5% in the tube exposure group was significantly less (P=0.041 compared with the control group (37.5%. Comparisons of the type and position of the drainage implant were not significantly different between the two groups. The average time to tube exposure was 17.2±18.0 months after implantation of the drainage device. In both univariate and multivariate analyses, younger age (P=0.005 and P=0.027 and inflammation prior to tube exposure (P≤0.001 and P=0.004 were significant risk factors. Diabetes was a significant risk factor only in the univariate analysis (P=0.027.Conclusion: Younger age and inflammation were significant risk factors for tube exposure after drainage implant surgery. Keywords: glaucoma drainage implant complications, Ahmed Glaucoma Valve, Baerveldt implant, tube erosion, pericardial patch graft

  9. The kinetics of porous insertion electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Atlung, S; West, K [British Columbia Univ., Vancouver (Canada)

    1989-05-01

    The principles of porous electrodes are discussed as well as the discharge of the insertion compound, the working potential, transport in the electrolyte, the time dependence of the electrolyte concentration, and modeling of the porous electrode. The simulation of a TiS2 porous electrode and the composite insertion electrode are considered as well. The influence of electrode thickness and porosity in a typical porous TiS2 electrode is revealed. It is shown that the use of insertion compounds as battery electrodes is limited by the requirement that the inserted ion must be distributed in the interior of the insertion compound particle. 15 refs.

  10. [Use of the Pentax-AWS videolaryngoscope for bougie-assisted exchange of tracheal tubes].

    Science.gov (United States)

    Kishii, Miki; Asai, Takashi; Nagata, Atsushi; Shingu, Koh

    2009-06-01

    A gum elastic bougie can be useful for tube exchange. One major problem with this technique is that it may not possible to pass a new tube over the bougie into the trachea, because the tip of the tube can collide with tissues around the glottis. We report a case in which tube exchange using the bougie was difficult, but the Pentax-AWS videolaryngoscope enabled tracheal intubation. In a 62-year-old trauma patient with head and neck stabilized using a Halo vest, was scheduled for emergency fixation of the neck. Exchange of a polyvinylchloride tube to a reinforced tube was planned. A bougie was passed through the old tube, removing the tube, and a new tube was advanced over the bougie, but it was impossible to advance the tube into the trachea. Insertion of a Macintosh laryngoscope did not enable intubation. The new tube was removed from the bougie, attached to the Pentax-AWS videolaryngoscope, and the tube (with the Pentax-AWS) was passed over the bougie. Although it was not possible to see the glottis with the Pentax-AWS, the tube was easily advanced over the bougie into the trachea. Operation went on uneventfully. We believe that, when it is difficult to advance a tracheal tube over a tube exchanger, the use of the Pentax-AWS may facilitate intubation.

  11. The impact of a chest tube management protocol on the outcome of trauma patients with tube thoracostomy.

    Science.gov (United States)

    de Abreu, Emanuelle Maria Sávio; Machado, Carla Jorge; Pastore Neto, Mario; de Rezende Neto, João Baptista; Sanches, Marcelo Dias

    2015-01-01

    to investigate the effect of standardized interventions in the management of tube thoracostomy patients and to assess the independent effect of each intervention. A chest tube management protocol was assessed in a retrospective cohort study. The tube thoracostomy protocol (TTP) was implemented in August 2012, and consisted of: antimicrobial prophylaxis, chest tube insertion in the operating room (OR), admission post chest tube thoracostomy (CTT) in a hospital floor separate from the emergency department (ED), and daily respiratory therapy (RT) sessions post-CTT. The inclusion criteria were, hemodynamic stability, patients between the ages of 15 and 59 years, and injury severity score (ISS) chest wall, lung, and pleura. During the study period 92 patients were managed according to the standardized protocol. The outcomes of those patients were compared to 99 patients treated before the TTP. Multivariate logistic regression analysis was performed to assess the independent effect of each variable of the protocol on selected outcomes. Demographics, injury severity, and trauma mechanisms were similar among the groups. As expected, protocol compliance increased after the implementation of the TTP. There was a significant reduction (pchest tube days. Respiratory therapy was independently linked to significant reduction (pchest tube insertion was associated with significant (ptrauma patients.

  12. Comparison of bougie-guided insertion of Proseal tm laryngeal mask airway with digital technique in adults

    Directory of Open Access Journals (Sweden)

    Anand Kuppusamy

    2010-01-01

    Full Text Available The Proseal TM laryngeal mask airway (PLMA TM , Laryngeal Mask Company, UK was designed to improve ventilatory characteristics and offer protection against regurgitation and gastric insufflation. The PLMA is a modified laryngeal mask airway with large ventral cuff, dorsal cuff and a drain tube. These modifications improve seal around glottis and enable better ventilatory characteristics. The drain tube prevents gastric distension and offers protection against aspiration. There were occasional problems, like failed insertion and inadequate ventilation, in placing PLMA TM using the classical digital technique. To overcome these problems, newer placement techniques like thumb insertion technique, introducer tool placement and gum elastic bougie (GEB-aided placement were devised. We compared classical digital placement of PLMA TM with gum elastic bougie-aided technique in 60 anaesthetised adult patients (with 30 patients in each group with respect to number of attempts to successful placement, effective airway time, airway trauma during insertion, postoperative airway morbidity and haemodynamic response to insertion. The number of attempts to successful placement, airway trauma during insertion and haemodynamic response to insertion were comparable among the two groups, while effective airway time and oropharyngeal leak pressure were significantly higher in bougie- guided insertion of PLMA. Postoperatively, sore throat was more frequent with digital technique while dysphagia was more frequent with bougie-guided technique. Hence gum elastic bougie guided, laryngoscope aided insertion of PLMA is an excellent alternate to classical digital technique.

  13. Wear plates control rod guide tubes top internal reactor vessel C. N. VANDELLOS II

    International Nuclear Information System (INIS)

    2010-01-01

    The guide tubes for control rods forming part of the upper internals of the reactor vessel, its function is to guide the control rod to permit its insertion in the reactor core. These guide tubes are suspended from the upper support plate which are fixed by bolts and extending to the upper core plate which is fastened by clamping bolts (split pin) to prevent lateral displacement of the guide tubes, while allowing axial expansion.

  14. Randomized clinical trial of pigtail catheter versus chest tube in injured patients with uncomplicated traumatic pneumothorax.

    Science.gov (United States)

    Kulvatunyou, N; Erickson, L; Vijayasekaran, A; Gries, L; Joseph, B; Friese, R F; O'Keeffe, T; Tang, A L; Wynne, J L; Rhee, P

    2014-01-01

    Small pigtail catheters appear to work as well as the traditional large-bore chest tubes in patients with traumatic pneumothorax, but it is not known whether the smaller pigtail catheters are associated with less tube-site pain. This study was conducted to compare tube-site pain following pigtail catheter or chest tube insertion in patients with uncomplicated traumatic pneumothorax. This prospective randomized trial compared 14-Fr pigtail catheters and 28-Fr chest tubes in patients with traumatic pneumothorax presenting to a level I trauma centre from July 2010 to February 2012. Patients who required emergency tube placement, those who refused and those who could not respond to pain assessment were excluded. Primary outcomes were tube-site pain, as assessed by a numerical rating scale, and total pain medication use. Secondary outcomes included the success rate of pneumothorax resolution and insertion-related complications. Forty patients were enrolled. Baseline characteristics of 20 patients in the pigtail catheter group were similar to those of 20 patients in the chest tube group. No patient had a flail chest or haemothorax. Pain scores related to chest wall trauma were similar in the two groups. Patients with a pigtail catheter had significantly lower mean(s.d.) tube-site pain scores than those with a chest tube, at baseline after tube insertion (3.2(0.6) versus 7.7(0.6); P pneumothorax, use of a 14-Fr pigtail catheter is associated with reduced pain at the site of insertion, with no other clinically important differences noted compared with chest tubes. NCT01537289 (http://clinicaltrials.gov). © 2013 BJS Society Ltd. Published by John Wiley & Sons Ltd.

  15. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... YouTube Videos » NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: ...

  16. The painting technique of the vaulted roof at the Saadian Tomb of Mulay Ahmed Al Mansour: preliminary results

    International Nuclear Information System (INIS)

    Andreotti, A.; Colombini, M. P.; Lluveras, A.; Raihan, M.; Ibnoussina, M.; Tanouti, B.; Boujamid, A.

    2010-01-01

    The Saadian tombs date back from the time of the sultan Ahmed Al Mansour (1578-1603). the tombs have, because of the beauty of their decoration, been a major attraction for visitors of Marrakech. The central mausoleum, the Hall of Twelve Columns, contains the tombs of ahmed Al Mansour and his family. It's dark, lavish, and ornate, with a huge vaulted roof, carved cedar doors and moucharabia (carved wooden screens traditionally to separate the sexes), and gray Italian marble columns. Samples from the painted roof have been collected and are currently under analysis to understand the executive technique used in its decoration. Generally, samples from painted works of art are characterised by the presence of several different organic materials together with pigments, fillers and dryers. A GC-MS analytical procedure for the characterisation of lipids, waxes, resins, pitch, tar, proteinaceous and polysaccharide material in the same paint micro-sample is applied to each collected micro-sample. The analytical procedure is based on a multi step sample pre-treatment that is able to separate the various organic components into different fractions (polysacharide, lipiresinous and proteinaceous), which are separately analyzed by GC-MS after purification and derivatisation. In particuler, this method achieves: -- the identification of proteinaceous binder (egg, collagen, casein) on the basis of the quantitative determination of the amino acid profile processed by principal component analysis -- the identification of lipids (linseed oil, poppy seed oil, walnut oil and egg), plant resins, animal resins,tar or pitches and natural waxes on the basis of the quantitative determination of fatty and dicarboxylic acids, and molecular pattern recognition of alchols and hydrocarbons and terpenic molecular markers -- the identification of th polysaccharide binder( starch, tragacanth gum, arabic gum, fruit tree gum, guar gum, karayagum) on the basis of the quantitative

  17. Chest tube drainage of pleural effusions--an audit of current practice and complications at Hutt Hospital.

    Science.gov (United States)

    Epstein, Erica; Jayathissa, Sisira; Dee, Stephen

    2012-05-11

    The aims of the study were to review small-bore chest tube insertion practices for drainage of pleural fluid at Hutt Valley District Health Board (HVDHB), to assess complications, and compare the findings with international data. Retrospective analysis of clinical records was completed on all chest tube insertions for drainage of pleural fluid at HVDHB from December 2008 to November 2009. Descriptive statistics were used to present demographics and tube-associated complications. Comparison was made to available similar international data. Small-bore tubes comprised 59/65 (91%) chest tube insertions and 23/25 (92%) complications. Available comparative data was limited. Ultrasound was used in 36% of insertions. Nearly half of chest drains placed for empyema required subsequent cardiothoracic surgical intervention. Chest drain complication rates at HVDHB were comparable to those seen internationally. Referral rates to cardiothoracic surgery for empyema were within described ranges. The importance of procedural training for junior medical staff, optimising safety of drain insertions with ultrasound guidance, and clear clinical governance for chest tube insertions are important in minimising harm from this procedure. Specialist societies need to take a leadership in providing guidance on chest drain insertions to secondary and tertiary hospitals in Australia and New Zealand.

  18. Chest tube placement in thorax trauma - comparison chest X-ray and computed tomography (CT)

    International Nuclear Information System (INIS)

    Heim, P.; Maas, R.; Buecheler, E.; Tesch, C.

    1998-01-01

    Estimation of chest tube placement in patients with thoracic trauma with regard to chest tube malposition in chest radiography in the supine position compared to additional computed tomography of the thorax. Material and methods: Apart from compulsory chest radiography after one or multiple chest tube insertions, 31 severely injured patients with thoracic trauma underwent a CT scan of the thorax. These 31 patients with 40 chest tubes constituted the basis for the present analysis. Results: In chest radiography in the supine position there were no chest tube malpositions (n=40); In the CT scans 25 correct positions, 7 pseudo-malpositions, 6 intrafissural and 2 intrapulmonary malpositions were identified. Moreover 16 sufficient, 18 insufficient and 6 indifferent functions of the chest tubes were seen. Conclusion: In case of lasting clinical problems and questionable function of the chest tube, chest radiography should be supplemented by a CT scan of the thorax in order to estimate the position of the chest tube. (orig.) [de

  19. Laryngeal tube use in out-of-hospital cardiac arrest by paramedics in Norway

    Directory of Open Access Journals (Sweden)

    Sunde Geir A

    2012-12-01

    Full Text Available Abstract Background Although there are numerous supraglottic airway alternatives to endotracheal intubation, it remains unclear which airway technique is optimal for use in prehospital cardiac arrests. We evaluated the use of the laryngeal tube (LT as an airway management tool among adult out-of-hospital cardiac arrest (OHCA patients treated by our ambulance services in the Haukeland and Innlandet hospital districts. Methods Post-resuscitation forms and data concerning airway management in 347 adult OHCA victims were retrospectively assessed with regard to LT insertion success rates, ease and speed of insertion and insertion-related problems. Results A total of 402 insertions were performed on 347 OHCA patients. Overall, LT insertion was successful in 85.3% of the patients, with a 74.4% first-attempt success rate. In the minority of patients (n = 46, 13.3%, the LT insertion time exceeded 30 seconds. Insertion-related problems were recorded in 52.7% of the patients. Lack of respiratory sounds on auscultation (n = 100, 28.8%, problematic initial tube positioning (n = 85, 24.5%, air leakage (n = 61, 17.6%, vomitus/aspiration (n = 44, 12.7%, and tube dislocation (n = 17, 4.9% were the most common problems reported. Insertion difficulty was graded and documented for 95.4% of the patients, with the majority of insertions assessed as being “Easy” (62.5% or “Intermediate” (24.8%. Only 8.1% of the insertions were considered to be “Difficult”. Conclusions We found a high number of insertion related problems, indicating that supraglottic airway devices offering promising results in manikin studies may be less reliable in real-life resuscitations. Still, we consider the laryngeal tube to be an important alternative for airway management in prehospital cardiac arrest victims.

  20. Pediatric cuffed endotracheal tubes

    Directory of Open Access Journals (Sweden)

    Neerja Bhardwaj

    2013-01-01

    Full Text Available Endotracheal intubation in children is usually performed utilizing uncuffed endotracheal tubes for conduct of anesthesia as well as for prolonged ventilation in critical care units. However, uncuffed tubes may require multiple changes to avoid excessive air leak, with subsequent environmental pollution making the technique uneconomical. In addition, monitoring of ventilatory parameters, exhaled volumes, and end-expiratory gases may be unreliable. All these problems can be avoided by use of cuffed endotracheal tubes. Besides, cuffed endotracheal tubes may be of advantage in special situations like laparoscopic surgery and in surgical conditions at risk of aspiration. Magnetic resonance imaging (MRI scans in children have found the narrowest portion of larynx at rima glottides. Cuffed endotracheal tubes, therefore, will form a complete seal with low cuff pressure of <15 cm H 2 O without any increase in airway complications. Till recently, the use of cuffed endotracheal tubes was limited by variations in the tube design marketed by different manufacturers. The introduction of a new cuffed endotracheal tube in the market with improved tracheal sealing characteristics may encourage increased safe use of these tubes in clinical practice. A literature search using search words "cuffed endotracheal tube" and "children" from 1980 to January 2012 in PUBMED was conducted. Based on the search, the advantages and potential benefits of cuffed ETT are reviewed in this article.

  1. Establishing Decision Trees for Predicting Successful Postpyloric Nasoenteric Tube Placement in Critically Ill Patients.

    Science.gov (United States)

    Chen, Weisheng; Sun, Cheng; Wei, Ru; Zhang, Yanlin; Ye, Heng; Chi, Ruibin; Zhang, Yichen; Hu, Bei; Lv, Bo; Chen, Lifang; Zhang, Xiunong; Lan, Huilan; Chen, Chunbo

    2018-01-01

    Despite the use of prokinetic agents, the overall success rate for postpyloric placement via a self-propelled spiral nasoenteric tube is quite low. This retrospective study was conducted in the intensive care units of 11 university hospitals from 2006 to 2016 among adult patients who underwent self-propelled spiral nasoenteric tube insertion. Success was defined as postpyloric nasoenteric tube placement confirmed by abdominal x-ray scan 24 hours after tube insertion. Chi-square automatic interaction detection (CHAID), simple classification and regression trees (SimpleCart), and J48 methodologies were used to develop decision tree models, and multiple logistic regression (LR) methodology was used to develop an LR model for predicting successful postpyloric nasoenteric tube placement. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of these models. Successful postpyloric nasoenteric tube placement was confirmed in 427 of 939 patients enrolled. For predicting successful postpyloric nasoenteric tube placement, the performance of the 3 decision trees was similar in terms of the AUCs: 0.715 for the CHAID model, 0.682 for the SimpleCart model, and 0.671 for the J48 model. The AUC of the LR model was 0.729, which outperformed the J48 model. Both the CHAID and LR models achieved an acceptable discrimination for predicting successful postpyloric nasoenteric tube placement and were useful for intensivists in the setting of self-propelled spiral nasoenteric tube insertion. © 2016 American Society for Parenteral and Enteral Nutrition.

  2. Tracheostomy: from insertion to decannulation

    Science.gov (United States)

    Engels, Paul T.; Bagshaw, Sean M.; Meier, Michael; Brindley, Peter G.

    2009-01-01

    Tracheostomy is a common surgical procedure, and is increasingly performed in the intensive care unit (ICU) as opposed to the operating room. Procedural knowledge is essential and is therefore outlined in this review. We also review several high-quality studies comparing percutaneous dilational tracheostomy and open surgical tracheostomy. The percutaneous method has a comparable, if not superior, safety profile and lower cost compared with the open surgical approach; therefore the percutaneous method is increasingly chosen. Studies comparing early versus late tracheostomy suggest morbidity benefits that include less nosocomial pneumonia, shorter mechanical ventilation and shorter stay in the ICU. However, we discuss the questions that remain regarding the optimal timing of tracheostomy. We outline the potential acute and chronic complications of tracheostomy and their management, and we review the different tracheostomy tubes, their indications and when to remove them. PMID:19865580

  3. Conjunctival inclusion cyst following repair of tube erosion in a child with aphakic glaucoma, leading to endophthalmitis

    Directory of Open Access Journals (Sweden)

    Roy, Avik Kumar

    2015-05-01

    Full Text Available Introduction: Glaucoma in aphakia is a major long term complication following congenital cataract surgery. Implantation of glaucoma drainage device provides an effective approach to manage refractory paediatric glaucoma. However implant surgery in young individuals is not free of complications. The prompt detection and management of tube erosion is of utmost importance to prevent devastating sequel of endophthalmitis. Implantation cyst following repair of tube erosion has not been reported so far. This case illustrates the rare occurrence of inclusion cyst following repair of tube erosion, the possible causes and its consequences. Case description: A 2-year-old child with aphakia developed intractable glaucoma. Following a failed glaucoma filtering surgery he underwent sequential Ahmed Glaucoma Valve implantation in both the eyes. Six weeks following right eye surgery, the child presented with conjunctival erosion overlying the tube, which was treated with scleral patch graft and conjunctival advancement. One month after the repair of tube erosion, the child presented with implantation cyst under the scleral patch graft, which was treated by drainage with a 29G needle. The child presented with endophthalmitis of his right eye following an episode of bilateral conjunctivitis. This was managed by an emergency pars plana vitrectomy, intraocular antibiotics and tube excision. At the last follow up visit, the IOP was 20 mmHg with 2 topical antiglaucoma medications in the right eye following a trans scleral photocoagulation.Discussion: Lifelong careful follow-up of paediatric eyes with implant surgery is mandatory to look for complication such as tube erosion. It is important to place additional sutures to secure the patch graft during implantation of glaucoma drainage devices in children to prevent graft displacement and consequent tube erosion. During repair of tube erosion, it is crucial to remove all the conjunctival epithelium around the tube

  4. Conjunctival inclusion cyst following repair of tube erosion in a child with aphakic glaucoma, leading to endophthalmitis.

    Science.gov (United States)

    Roy, Avik Kumar; Senthil, Sirisha

    2015-01-01

    Glaucoma in aphakia is a major long term complication following congenital cataract surgery. Implantation of glaucoma drainage device provides an effective approach to manage refractory paediatric glaucoma. However implant surgery in young individuals is not free of complications. The prompt detection and management of tube erosion is of utmost importance to prevent devastating sequel of endophthalmitis. Implantation cyst following repair of tube erosion has not been reported so far. This case illustrates the rare occurrence of inclusion cyst following repair of tube erosion, the possible causes and its consequences. A 2-year-old child with aphakia developed intractable glaucoma. Following a failed glaucoma filtering surgery he underwent sequential Ahmed Glaucoma Valve implantation in both the eyes. Six weeks following right eye surgery, the child presented with conjunctival erosion overlying the tube, which was treated with scleral patch graft and conjunctival advancement. One month after the repair of tube erosion, the child presented with implantation cyst under the scleral patch graft, which was treated by drainage with a 29G needle. The child presented with endophthalmitis of his right eye following an episode of bilateral conjunctivitis. This was managed by an emergency pars plana vitrectomy, intraocular antibiotics and tube excision. At the last follow up visit, the IOP was 20 mmHg with 2 topical antiglaucoma medications in the right eye following a trans scleral photocoagulation. Lifelong careful follow-up of paediatric eyes with implant surgery is mandatory to look for complication such as tube erosion. It is important to place additional sutures to secure the patch graft during implantation of glaucoma drainage devices in children to prevent graft displacement and consequent tube erosion. During repair of tube erosion, it is crucial to remove all the conjunctival epithelium around the tube, thus not to incorporate epithelial tissue within the surgical

  5. Lunar Lava Tube Sensing

    Science.gov (United States)

    York, Cheryl Lynn; Walden, Bryce; Billings, Thomas L.; Reeder, P. Douglas

    1992-01-01

    Large (greater than 300 m diameter) lava tube caverns appear to exist on the Moon and could provide substantial safety and cost benefits for lunar bases. Over 40 m of basalt and regolith constitute the lava tube roof and would protect both construction and operations. Constant temperatures of -20 C reduce thermal stress on structures and machines. Base designs need not incorporate heavy shielding, so lightweight materials can be used and construction can be expedited. Identification and characterization of lava tube caverns can be incorporated into current precursor lunar mission plans. Some searches can even be done from Earth. Specific recommendations for lunar lava tube search and exploration are (1) an Earth-based radar interferometer, (2) an Earth-penetrating radar (EPR) orbiter, (3) kinetic penetrators for lunar lava tube confirmation, (4) a 'Moon Bat' hovering rocket vehicle, and (5) the use of other proposed landers and orbiters to help find lunar lava tubes.

  6. Categorising YouTube

    DEFF Research Database (Denmark)

    Simonsen, Thomas Mosebo

    2011-01-01

    This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC) of YouTube. The article investigates the construction of navigation processes on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube......’s technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition...... and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within...

  7. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1983-08-01

    A review of the performance of steam generator tubes in 110 water-cooled nuclear power reactors showed that tubes were plugged at 46 (42 percent) of the reactors. The number of tubes removed from service increased from 1900 (0.14 percent) in 1980 to 4692 (0.30 percent) in 1981. The leading causes of tube failures were stress corrosion cracking from the primary side, stress corrosion cracking (or intergranular attack) from the secondary side and pitting corrosion. The lowest incidence of corrosion-induced defects from the secondary side occurred in reactors that used all-volatile treatment since start-up. At one reactor a large number of degraded tubes were repaired by sleeving which is expected to become an important method of tube repair in the future

  8. Sequential cooling insert for turbine stator vane

    Science.gov (United States)

    Jones, Russel B

    2017-04-04

    A sequential flow cooling insert for a turbine stator vane of a small gas turbine engine, where the impingement cooling insert is formed as a single piece from a metal additive manufacturing process such as 3D metal printing, and where the insert includes a plurality of rows of radial extending impingement cooling air holes alternating with rows of radial extending return air holes on a pressure side wall, and where the insert includes a plurality of rows of chordwise extending second impingement cooling air holes on a suction side wall. The insert includes alternating rows of radial extending cooling air supply channels and return air channels that form a series of impingement cooling on the pressure side followed by the suction side of the insert.

  9. Development of fabrication technology for copper canisters with cast inserts. Status report in August 2001

    International Nuclear Information System (INIS)

    Andersson, Claes-Goeran

    2002-04-01

    This report contains an account of the results of trial fabrication of copper canisters with cast inserts carried out during the period 1998 - 2001. The work of testing of fabrication methods is being focused on a copper thickness of 50 mm. Occasional canisters with 30 mm copper thickness are being fabricated for the purpose of gaining experience and evaluating fabrication and inspection methods for such canisters. For the fabrication of copper tubes, SKB has concentrated its efforts on seamless tubes made by extrusion and pierce and draw processing. Five tubes have been extruded and two have been pierced and drawn during the period. Materials testing has shown that the resultant structure and mechanical properties of these tubes are good. Despite certain problems with dimensional accuracy, it can be concluded that both of these methods can be developed for use in the serial production of SKB' copper tubes. No new trial fabrication with roll forming of copper plate and longitudinal welding has been done. This method is nevertheless regarded as a potential alternative. Copper lids and bottoms are made by forging of continuous-cast bars. The forged blanks are machined to the desired dimensions. Due to the Canister Laboratory's need for lids to develop the technique for sealing welding, a relatively large number of forged blanks have been fabricated. It is noted in the report that the grain size obtained in lids and bottoms is much coarser than in fabricated copper tubes. Development work has been commenced for the purpose of optimizing the forging process. Nine cast inserts have been cast during the three-year period. The results of completed material testing of test pieces taken at different places along the length of the inserts have in several cases shown an unacceptable range of variation in strength properties and structure. In the continued work, insert fabrication will be developed in terms of both casting technique and iron composition. Development work on

  10. Rectangular drift tube characteristics

    International Nuclear Information System (INIS)

    Denisov, D.S.; Musienko, Yu.V.

    1985-01-01

    Results on the study of the characteristics of a 50 x 100 mm aluminium drift tube are presented. The tube was filled with argon-methane and argon-isobutane mixtures. With 16 per cent methane concentration the largest deviation from a linear relation between the drift time and the drift path over 50 mm is less than 2 mm. The tube filled with argon-isobutane mixture is capable of operating in a limited streamer mode

  11. Insertion devices at the advanced photon source

    International Nuclear Information System (INIS)

    Moog, E.R.

    1996-01-01

    The insertion devices being installed at the Advanced Photon Source cause the stored particle beam to wiggle, emitting x-rays with each wiggle. These x-rays combine to make an intense beam of radiation. Both wiggler and undulator types of insertion devices are being installed; the characteristics of the radiation produced by these two types of insertion devices are discussed, along with the reasons for those characteristics

  12. Node insertion in Coalescence Fractal Interpolation Function

    International Nuclear Information System (INIS)

    Prasad, Srijanani Anurag

    2013-01-01

    The Iterated Function System (IFS) used in the construction of Coalescence Hidden-variable Fractal Interpolation Function (CHFIF) depends on the interpolation data. The insertion of a new point in a given set of interpolation data is called the problem of node insertion. In this paper, the effect of insertion of new point on the related IFS and the Coalescence Fractal Interpolation Function is studied. Smoothness and Fractal Dimension of a CHFIF obtained with a node are also discussed

  13. Categorising YouTube

    OpenAIRE

    Simonsen, Thomas Mosebo

    2011-01-01

    This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC) of YouTube. The article investigates the construction of navigation processes on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a...

  14. Pressure tube reactor

    International Nuclear Information System (INIS)

    Susuki, Akira; Murata, Shigeto; Minato, Akihiko.

    1993-01-01

    In a pressure tube reactor, a reactor core is constituted by arranging more than two units of a minimum unit combination of a moderator sealing pipe containing a calandria tube having moderators there between and a calandria tube and moderators. The upper header and a lower header of the calandria tank containing moderators are communicated by way of the moderator sealing tube. Further, a gravitationally dropping mechanism is disposed for injecting neutron absorbing liquid to a calandria gas injection portion. A ratio between a moderator volume and a fuel volume is defined as a function of the inner diameter of the moderator sealing tube, the outer diameter of the calandria tube and the diameter of fuel pellets, and has no influence to intervals of a pressure tube lattice. The interval of the pressure tube lattice is enlarged without increasing the size of the pressure tube, to improve production efficiency of the reactor and set a coolant void coefficient more negative, thereby enabling to improve self controllability and safety. Further, the reactor scram can be conducted by injecting neutron absorbing liquid. (N.H.)

  15. Heated Tube Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Heated Tube Facility at NASA GRC investigates cooling issues by simulating conditions characteristic of rocket engine thrust chambers and high speed airbreathing...

  16. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1984-10-01

    A review of the performance of steam generator tubes in 116 water-cooled nuclear power reactors showed that tubes were plugged at 54 (46 percent) of the reactors. The number of tubes removed from service decreased from 4 692 (0.30 percent) in 1981 to 3 222 (0.20 percent) in 1982. The leading causes of tube failures were stress corrosion cracking from the primary side, stress corrosion cracking (or intergranular attack) from the secondary side and pitting corrosion. The lowest incidence of corrosion-induced defects from the secondary side occurred in reactors that have used only volatile treatment, with or without condensate demineralization

  17. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Tapping, R.L.; Stipan, L.

    1992-03-01

    A survey of steam generator operating experience for 1986 has been carried out for 184 pressurized water and pressurized heavy-water reactors, and 1 water-cooled, graphite-moderated reactor. Tubes were plugged at 75 of the reactors (40.5%). In 1986, 3737 tubes were plugged (0.14% of those in service) and 3148 tubes were repaired by sleeving. A small number of reactors accounted for the bulk of the plugged tubes, a phenomenon consistent with previous years. For 1986, the available tubesheet sludge data for 38 reactors has been compiled into tabular form, and sludge/deposit data will be incorporated into all future surveys

  18. Insertion material for controlling reactivity

    International Nuclear Information System (INIS)

    Baba, Iwao.

    1994-01-01

    Moderators and a group of suspended materials having substantially the same density as the moderator are sealed in a hollow rod vertically inserted to a fuel assembly. Specifically, the group of suspended materials is adapted to have a density changing stepwise from density of the moderator at the exit temperature of the reactor core to that at the inlet temperature of the reactor core. Reactivity is selectively controlled for a portion of high power and a portion of high reactivity by utilizing the density of the moderator and the distribution of the density. That is, if the power distribution is flat, the density of the moderators changes at a constant rate over the vertical direction of the reactor core and the suspended materials stay at a portion of the same density, to form a uniform distribution. Further, upon reactor shutdown, since the liquid temperature of the moderators is lowered and the density is increased, all of beads are collected at the upper portion to remove water at the upper portion of the reactor core of low burnup degree thereby selectively controlling the reactivity at a portion of high power and a portion of high reactivity. (N.H.)

  19. [Rare problem with the insertion of a Supreme™ laryngeal mask airway device. Case of the trimester].

    Science.gov (United States)

    2014-03-01

    A breast tumor was resected under general anesthesia. After induction, the airway was managed with a Supreme™ laryngeal mask airway device. The insertion of the laryngeal mask airway device, the insertion of the orogastric tube through the drain tube, as well as the mechanical ventilation, were very difficult from the beginning. On removing the laryngeal mask airway device to solve the problem, it was observed that the drain tube was broken, and the orogastric tube had passed into the anterior, laryngeal part of the device through the split. It was later found out that the laryngeal mask airway device, as well as the whole manufacturing batch, had suffered a design modification: the cuff was constructed with a softer material without reinforcement in the tip, and the drain tube had a heat-sealing defect that facilitated the break. The incident was reported to the local supplier and the manufacturer, and the defective batch of laryngeal mask airway devices was recalled. The incident was also reported to other hospitals via SENSAR, to warn other users of the potential dangers of the design modification in the Supreme™ laryngeal mask airway. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  20. Steam generator tube failures

    International Nuclear Information System (INIS)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service

  1. Cotton transformation via pollen tube pathway.

    Science.gov (United States)

    Wang, Min; Zhang, Baohong; Wang, Qinglian

    2013-01-01

    Although many gene transfer methods have been employed for successfully obtaining transgenic cotton, the major constraint in cotton improvement is the limitation of genotype because the majority of transgenic methods require plant regeneration from a single transformed cell which is limited by cotton tissue culture. Comparing with other plant species, it is difficult to induce plant regeneration from cotton; currently, only a limited number of cotton cultivars can be cultured for obtaining regenerated plants. Thus, development of a simple and genotype-independent genetic transformation method is particularly important for cotton community. In this chapter, we present a simple, cost-efficient, and genotype-independent cotton transformation method-pollen tube pathway-mediated transformation. This method uses pollen tube pathway to deliver transgene into cotton embryo sacs and then insert foreign genes into cotton genome. There are three major steps for pollen tube pathway-mediated genetic transformation, which include injection of -foreign genes into pollen tube, integration of foreign genes into plant genome, and selection of transgenic plants.

  2. Combined trabeculotomy-trabeculectomy versus Ahmed valve implantation for refractory primary congenital glaucoma in Egyptian patients: a long-term follow-up

    Science.gov (United States)

    Helmy, Hazem

    2016-01-01

    Introduction Primary congenital glaucoma (PCG) is the most common type of glaucoma in pediatric patients. The aim of this study was to compare the effectiveness of combined trabeculotomy-trabeculectomy versus Ahmed valve implantation for cases of PCG refractory to traditional incisional angle surgery (goniotomy and trabeculotomy) in the Egyptian population. Methods The study was conducted in the Glaucoma Clinic of the Research Institute of Ophthalmology (Egypt). The study included 66 eyes of 66 patients (in two groups) with advanced PCG who had previous failed goniotomy, trabeculotomy, or both. Group 1 included 33 patients who underwent trabeculotomy-trabeculectomy procedures; group 2 included 33 patients who underwent FP 8 Ahmed valve implantation. The main outcome measures were intraocular pressure (IOP) reduction, corneal diameter, and axial length stability in both groups. Secondary outcome measures included detection of complications in both groups. Results The average ages of the patients were 13.5 ± 3.9 months and 15.3 ± 5.8 months in groups 1 and 2, respectively. Ten patients (30.3%) in group 1 and 9 patients (27.3%) in group 2 had family histories of PCG. Positive consanguinity was present in 26 patients (78.8%) in group 1 and in 27 patients (81.8%) in group 2. In group 1, the mean intraocular pressure (IOP) value decreased from 33.6 ± 3.4 mmHg preoperatively to 13.8 ± 0.6, 16.9 ± 1.5, 18.2 ± 2.5, 19.8 ± 3.6, and 20.2 ± 3.1 mmHg in the first postoperative month and after years 1, 2, 3, and 4, respectively (p Ahmed valve implantation are suitable options in advanced PCG with failed trabeculotomy and goniotomy. Ahmed valve implanation has a better long-term survival, but trabeculotomy-trabeculectomy provides a second chance for surgical intervention. PMID:27053995

  3. Method for shaping polyethylene tubing

    Science.gov (United States)

    Kramer, R. C.

    1981-01-01

    Method forms polyethylene plastic tubing into configurations previously only possible with metal tubing. By using polyethylene in place of copper or stain less steel tubing inlow pressure systems, fabrication costs are significantly reduced. Polyethylene tubing can be used whenever low pressure tubing is needed in oil operations, aircraft and space applications, powerplants, and testing laboratories.

  4. Pyrotechnic Tubing Connector

    Science.gov (United States)

    Graves, Thomas J.; Yang, Robert A.

    1988-01-01

    Tool forms mechanical seal at joint without levers or hydraulic apparatus. Proposed tool intended for use in outer space used on Earth by heavily garbed workers to join tubing in difficult environments. Called Pyrotool, used with Lokring (or equivalent) fittings. Piston slides in cylinder when pushed by gas from detonating pyrotechnic charge. Impulse of piston compresses fittings, sealing around butting ends of tubes.

  5. Numerical simulation of fluid flow and heat transfer in a concentric tube heat exchanger

    International Nuclear Information System (INIS)

    Mokamati, S.V.; Prasad, R.C.

    2003-01-01

    In this paper, numerical simulation of a concentric tube heat exchanger is presented to determine the convective heat transfer coefficient and friction factor in a smooth tube. Increasing the convective heat transfer coefficient can increase heat transfer rate in a concentric tube heat exchanger from a given tubular surface area. This can be achieved by using heat transfer augmentation devices. This work constitutes the initial phase of the numerical simulation of heat transfer from tubes employing augmentation devices, such as twisted tapes, wire-coil inserts, for heat transfer enhancement. A computational fluid dynamics (CFD) simulation tool was developed with CFX software and the results obtained from the simulations are validated with the empirical correlations for a smooth tube heat exchanger. The difficulties associated with the simulation of a heat exchanger augmented with wire-coil inserts are discussed. (author)

  6. Molybdenum Tube Characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Beaux II, Miles Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-07

    Chemical vapor deposition (CVD) techniques have been utilized to produce free-standing molybdenum tubes with the end goal of nuclear fuel clad applications. In order to produce tubes with properties desirable for this application, deposition rates were lowered requiring long deposition durations on the order of 50 hours. Standard CVD methods as well as fluidized-bed CVD (FBCVD) methods were applied towards these objectives. Characterization of the tubes produced in this manner revealed material suitable for fuel clad applications, but lacking necessary uniformity across the length of the tubes. The production of freestanding Mo tubes that possess the desired properties across their entire length represents an engineering challenge that can be overcome in a next iteration of the deposition system.

  7. Measurement and computation for sag of calandria tube due to irradiation creep in PHWR

    International Nuclear Information System (INIS)

    Son, S. M.; Lee, W. R.; Lee, S. K.; Lee, J. S.; Kim, T. R.; Na, B. K.; Namgung I.

    2003-01-01

    Calandria tubes and Liquid Injection Shutdown System(LISS) tubes in a Pressurized Heavy Water Reactor(PHWR) are to sag due to irradiation creep and growth during plant operation. When the sag of calandria tube becomes bigger, the calandria tube possibly comes in contact with LISS tube crossing beneath the calandria tube. The contact subsequently may cause the damage on the calandria tube resulting in unpredicted outage of the plant. It is therefore necessary to check the gap between the two tubes in order to periodically confirm no contact by using a proper measure during the plant life. An ultrasonic gap measuring probe assembly which can be inserted into two viewing ports of the calandria was developed in Korea and utilized to measure the sags of both tubes in the PHWR. It was found that the centerlines of calandria tubes and liquid injection shutdown system tubes can be precisely detected by ultrasonic wave. The gaps between two tubes were easily obtained from the relative distance of the measured centerline elevations of the tubes. Based on the irradiation creep equation and the measurement data, a computer program to calculate the sags was also developed. With the computer program, the sag at the end of plant life was predicted

  8. Experiments on vibration of heat exchanger tube arrays in cross flow

    International Nuclear Information System (INIS)

    Blevins, R.D.; Gibert, R.J.; Villard, B.

    1981-08-01

    A series of tests have been made at the Commissariat a l'Energie Atomique, in cooperation with General Atomic Company, SAN DIEGO (U.S.A.) on the flow-induced vibration of heat exchanger tube bundles in cross flow. These tests were made in air on tube bundles which simulated heat exchangers in the high temperature gas cooled reactors. The tests were of two types. In the first type, an instrumented tube was inserted at various locations into a tube bundle. Measurements were made of pressure at a number of points along the tube and about the circumference of the tube. These measurements were processed to obtain the spectra of turbulent pressure fluctuations on the tube, the spanwise correlation and the lift force. The second set of tests was made on tube bundles with flexible tubes. As the flow velocity was increased, these tests clearly show an instability. Nine tube configurations were tested with both plastic and metallic tubes and the effect of tube-to-tube difference in natural frequency was investigated

  9. Combined Scleral Flap with Donor Scleral Patch Graft for Anterior Tube Placement in Glaucoma Drainage Device Surgery

    Directory of Open Access Journals (Sweden)

    Jea H. Yu

    2016-01-01

    Full Text Available Purpose. To report a new technique for anterior placement of tubes for glaucoma drainage devices to reduce the risk of tube erosions. Methods. Retrospective review of select cases of Ahmed Valve surgery combined with the novel method of a limbal-based scleral flap covered by a scleral patch graft to cover the tube at the entrance through the limbus. Intraoperative and postoperative illustrations are shown to highlight the method of tube placement. Results. In this retrospective case series, 3 patients are presented illustrating the technique. Two had neovascular glaucoma and one had primary open-angle glaucoma (POAG. On average, intraocular pressure was reduced from 39±14 mmHg to 15±2 mmHg and the number of glaucoma medications was reduced from 4±1 to 0. Preoperative and most recent visual acuities were hand-motion (HM and HM, 20/60 and 20/50, and 20/70 and 20/30, respectively. Conclusion. The combination of a limbal-based scleral flap with scleral patch graft to cover the tube with glaucoma drainage devices may be an effective means to reduce erosion and protect against endophthalmitis.

  10. Combined Scleral Flap with Donor Scleral Patch Graft for Anterior Tube Placement in Glaucoma Drainage Device Surgery.

    Science.gov (United States)

    Yu, Jea H; Nguyen, Chuck; Gallemore, Esmeralda; Gallemore, Ron P

    2016-01-01

    Purpose . To report a new technique for anterior placement of tubes for glaucoma drainage devices to reduce the risk of tube erosions. Methods . Retrospective review of select cases of Ahmed Valve surgery combined with the novel method of a limbal-based scleral flap covered by a scleral patch graft to cover the tube at the entrance through the limbus. Intraoperative and postoperative illustrations are shown to highlight the method of tube placement. Results . In this retrospective case series, 3 patients are presented illustrating the technique. Two had neovascular glaucoma and one had primary open-angle glaucoma (POAG). On average, intraocular pressure was reduced from 39 ± 14 mmHg to 15 ± 2 mmHg and the number of glaucoma medications was reduced from 4 ± 1 to 0. Preoperative and most recent visual acuities were hand-motion (HM) and HM, 20/60 and 20/50, and 20/70 and 20/30, respectively. Conclusion . The combination of a limbal-based scleral flap with scleral patch graft to cover the tube with glaucoma drainage devices may be an effective means to reduce erosion and protect against endophthalmitis.

  11. A Comparative study of early postpartum IUCD insertion to interval IUCD insertion at Tertiary Care Centre

    OpenAIRE

    Roopal, Dr.; Bisht, Vandana

    2018-01-01

    Background: A Comparative study of early postpartum IUCD insertion to interval IUCD insertion at Tertiary Care Centre.Methods: This prospective study was conducted among 100 women at tertiary care centre, Haldwani, Nainital. Patients were divided in to two groups. Group A (n=50)-post placental insertion within 10 minutes of delivery of placenta. Group B (n=50)-Interval insertion after 6 weeks of delivery. Both groups were compared in terms of pain abdomen, bleeding, missing thread, expulsion,...

  12. Metallographic study of reconstitution welding in inserts of 1 cm{sup 3}; Estudio metalografico de soldaduras de reconstitucion en insertos de 1 cm{sup 3}

    Energy Technology Data Exchange (ETDEWEB)

    Romero C, J.; Garcia R, R.; Fernandez T, F.; Perez R, N.; Rocamontes A, M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2007-07-01

    In this article, the welding metallographic study carried out in Charpy test tubes reconstituted with notch in 'V', used in the surveillance programs of the vessel in nucleo electric plants is described. Inserts of 1 cm{sup 3} are used, where the inserts are usually rectangular of minimum 18 millimeters of length. The importance of using inserts of 1 cm{sup 3} is that the mechanical properties can be measured in another direction of the vessel steel, when changing the direction or sense of the notch in 'V' or the face where this notch is made in the insert. (Author)

  13. Laser Myringotomy Versus Ventilation Tubes In Otitis Media With Effusion.

    Science.gov (United States)

    Yousaf, Mohammad; Malik, Suhail Ahmad; Haroon, Tahir

    2016-01-01

    Otitis media with effusion (OME) is a leading cause of difficulty in hearing in paediatric population. Otitis media with effusion must be detected and managed early to prevent conductive hearing loss in children. It was aimed to compare results of laser myringotomy and ventilation tube insertion, in terms of hearing improvement and recurrence of Middle ear effusion (MEE). This randomized controlled trial was conducted from February 2012 to January 2015. Children of 4- 12 years of age with decreased hearing due to OME were included in the study. These children were investigated with pure tone audiometry (PTA) and tympanometry to confirm conductive hearing loss. Patients were put in 2 groups, group one comprised of patients treated with laser myringotomy and group 2, treated with ventilation tube insertion. The objective was to evaluate and compare results of the two procedures in terms of resolution of middle ear effusion (MEE) and improvement of hearing. The two procedures were also compared in terms of complications like otorrhea, persistence of perforation, hypertrophic scar and thinning of tympanic membrane (TM). Middle ear effusion cleared in 35 out of 68 ears with laser myringotomy (LM) as compared to 52 out of 62 ears with ventilation tubes (VT). The myringotomy was still patent in 21 ears treated with LM while tube was in site in 50 years with VT after 3 months. The hearing level improved with LM by 10-15 dB after first 3 months. The aim in Otitis media with effusion is ventilation of tympanic cavity. Laser myringotomy can be substitute to ventilation tube insertion (VT). But it remains patent for shorter time and less effective than VT. The ears with refractory or recurrent MEE should have VT insertion.

  14. A Note regarding Problems with Interaction and Varying Block Sizes in a Comparison of Endotracheal Tubes

    Directory of Open Access Journals (Sweden)

    Richard L. Einsporn

    2014-01-01

    Full Text Available A randomized clinical experiment to compare two types of endotracheal tubes utilized a block design where each of the six participating anesthesiologists performed tube insertions for an equal number of patients for each type of tube. Five anesthesiologists intubated at least three patients with each tube type, but one anesthesiologist intubated only one patient per tube type. Overall, one type of tube outperformed the other on all three effectiveness measures. However, analysis of the data using an interaction model gave conflicting and misleading results, making the tube with the better performance appear to perform worse. This surprising result was caused by the undue influence of the data for the anesthesiologist who intubated only two patients. We therefore urge caution in interpreting results from interaction models with designs containing small blocks.

  15. Central Solenoid Insert Technical Specification

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, Nicolai N [ORNL; Smirnov, Alexandre [ORNL

    2011-09-01

    The US ITER Project Office (USIPO) is responsible for the ITER central solenoid (CS) contribution to the ITER project. The Central Solenoid Insert (CSI) project will allow ITER validation the appropriate lengths of the conductors to be used in the full-scale CS coils under relevant conditions. The ITER Program plans to build and test a CSI to verify the performance of the CS conductor. The CSI is a one-layer solenoid with an inner diameter of 1.48 m and a height of 4.45 m between electric terminal ends. The coil weight with the terminals is approximately 820 kg without insulation. The major goal of the CSI is to measure the temperature margin of the CS under the ITER direct current (DC) operating conditions, including determining sensitivity to load cycles. Performance of the joints, ramp rate sensitivity, and stability against thermal or electromagnetic disturbances, electrical insulation, losses, and instrumentation are addressed separately and therefore are not major goals in this project. However, losses and joint performance will be tested during the CSI testing campaign. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at the Japan Atomic Energy Agency (JAEA), Naka, Japan. The industrial vendors (the Suppliers) will report to the USIPO (the Company). All approvals to proceed will be issued by the Company, which in some cases, as specified in this document, will also require the approval of the ITER Organization. Responsibilities and obligations will be covered by respective contracts between the USIPO, called Company interchangeably, and the industrial Prime Contractors, called Suppliers. Different stages of work may be performed by more than one Prime Contractor, as described in this specification. Technical requirements of the contract between the Company and the Prime Contractor will be covered by the Fabrication Specifications developed by the Prime Contractor based on this document and approved by

  16. The computational design of junctions by carbon nanotube insertion into a graphene matrix

    International Nuclear Information System (INIS)

    Mao Yuliang; Zhong Jianxin

    2009-01-01

    Using first-principles density functional theory calculations, two types of junction models constructed from armchair and zigzag carbon nanotube (CNT) insertion into a graphene matrix have been envisioned. It has been found that the insertion of the CNT into the graphene matrix leads to the formation of C-C covalent bonds between graphene and the CNT that distort the CNT geometry. However, the hydrogenation of the suspended carbon bonds on the graphene resumes the graphene-like structure of the pristine tube. The calculated band structure of armchair CNT insertion into graphene or hydrogenation graphene opens up a band gap and converts the metallic CNT into a semiconductor. For the zigzag CNT, the sp 3 hybridization between the graphene and nanotube alters the band structure of the tube significantly, whereas saturating the dangling bonds of terminal carbon atoms of graphene makes the CNT almost keep the same character of the bands as that in the pristine tube. The synthesis of our designed hybrid structures must be increasingly driven by an interest in molecules that not only have intriguing structures but also have special functions such as hydrogen storage.

  17. Automation in tube finishing bay

    International Nuclear Information System (INIS)

    Bhatnagar, Prateek; Satyadev, B.; Raghuraman, S.; Syama Sundara Rao, B.

    1997-01-01

    Automation concept in tube finishing bay, introduced after the final pass annealing of PHWR tubes resulted in integration of number of sub-systems in synchronisation with each other to produce final cut fuel tubes of specified length, tube finish etc. The tube finishing bay which was physically segregated into four distinct areas: 1. tube spreader and stacking area, 2. I.D. sand blasting area, 3. end conditioning, wad blowing, end capping and O.D. wet grinding area, 4. tube inspection, tube cutting and stacking area has been studied

  18. Insertion profiles of 4 headless compression screws.

    Science.gov (United States)

    Hart, Adam; Harvey, Edward J; Lefebvre, Louis-Philippe; Barthelat, Francois; Rabiei, Reza; Martineau, Paul A

    2013-09-01

    In practice, the surgeon must rely on screw position (insertion depth) and tactile feedback from the screwdriver (insertion torque) to gauge compression. In this study, we identified the relationship between interfragmentary compression and these 2 factors. The Acutrak Standard, Acutrak Mini, Synthes 3.0, and Herbert-Whipple implants were tested using a polyurethane foam scaphoid model. A specialized testing jig simultaneously measured compression force, insertion torque, and insertion depth at half-screw-turn intervals until failure occurred. The peak compression occurs at an insertion depth of -3.1 mm, -2.8 mm, 0.9 mm, and 1.5 mm for the Acutrak Mini, Acutrak Standard, Herbert-Whipple, and Synthes screws respectively (insertion depth is positive when the screw is proud above the bone and negative when buried). The compression and insertion torque at a depth of -2 mm were found to be 113 ± 18 N and 0.348 ± 0.052 Nm for the Acutrak Standard, 104 ± 15 N and 0.175 ± 0.008 Nm for the Acutrak Mini, 78 ± 9 N and 0.245 ± 0.006 Nm for the Herbert-Whipple, and 67 ± 2N, 0.233 ± 0.010 Nm for the Synthes headless compression screws. All 4 screws generated a sizable amount of compression (> 60 N) over a wide range of insertion depths. The compression at the commonly recommended insertion depth of -2 mm was not significantly different between screws; thus, implant selection should not be based on compression profile alone. Conically shaped screws (Acutrak) generated their peak compression when they were fully buried in the foam whereas the shanked screws (Synthes and Herbert-Whipple) reached peak compression before they were fully inserted. Because insertion torque correlated poorly with compression, surgeons should avoid using tactile judgment of torque as a proxy for compression. Knowledge of the insertion profile may improve our understanding of the implants, provide a better basis for comparing screws, and enable the surgeon to optimize compression. Copyright

  19. Short term outcome of Ahmed glaucoma valve implantation in management of refractory glaucoma in a tertiary hospital in Oman

    Science.gov (United States)

    Shah, Manali R.; Khandekar, Rajiv B.; Zutshi, Rajiv; Mahrooqi, Rahima

    2013-01-01

    Background: We present outcomes of Ahmed Glaucoma Valve (AGV) implantation in treating refractory glaucoma in a tertiary hospital in Oman. Refractory glaucoma was defined as previously failed conventional glaucoma surgery and an uncontrolled intraocular pressure (IOP) of more than 21 mm Hg despite treatment with three topical and/or oral therapy. Materials and Methods: This historical cohort study was conducted in 2010. Details of medical and surgical treatment were recorded. Ophthalmologists examined eyes and performed glaucoma surgeries using AGV. The best corrected distant vision, IOP, and glaucoma medications were prospectively reviewed on 1st day, 1st, 6th, 12th week postoperatively, and at the last follow up. Result: Glaucoma specialists examined and treated 40 eyes with refractory glaucoma of 39 patients (20 males + 19 females). Neo-vascular glaucoma was present in 23 eyes. Vision before surgery was glaucoma medications (2.38; SD 1.1) was reduced compared to the mean number of postoperative medications (1.92; SD 0.9) at 12 weeks. Conclusion: We succeeded in reducing visual disabilities and the number of anti-glaucoma medications used to treat refractory glaucoma by AGV surgery. PMID:23772122

  20. Tube thoracostomy in the management of pleural fluid collections.

    Science.gov (United States)

    Nwofor, A M E; Ekwunife, C N

    2006-06-01

    To determine the demographic pattern, indications and complications associated with tube thoracostomy in Nnamdi Azikiwe University Teaching Hospital (NAUTH) Nnewi. A 5-year review of case records of patients who underwent tube thoracostomy at NAUTH Nnewi between January 1999 and December 2003. Demographic data, clinical features, duration of drainage, complications and outcomes were analyzed. A total of 65 cases were studied, male: female ratio was 2.4:1. Eighteen patients (27.7%) were below 10 years of age. Infective cases accounted for 63.1% (41) of the cases that had tube thoracostomy. Forty-one patients (63.1%) had tube drainage for 10 days or less. Complication rate was 41.5% (27), mostly mild, with dislodgement of the tube accounting for about half. Failure rate of 13.7% (9) was recorded for the procedure. A mortality of 6.2% (4) was recorded but there was no procedure related death. Seven patients (10.8%) required further surgery. Tube thoracostomy is a simple and efficacious procedure for the treatment of pleural space collections. The safety of the procedure can be improved upon by adequate training in the insertion procedure, while proper selection of cases will reduce failure rate and unnecessary morbidity. Early resort to thoracoscopic or open surgery when tube thoracostomy is considered inappropriate or has failed will improve the success rate in the overall management of pleural fluid collections.

  1. Chest tube care in critically ill patient: A comprehensive review

    Directory of Open Access Journals (Sweden)

    Hanan Mohammed Mohammed

    2015-10-01

    Full Text Available Breathing is automatic. We don’t usually think too much about it unless we develop a problem. Lack of adequate ventilation and impairment of our respiratory system can quickly become life-threatening. There are many clinical conditions that may necessitate the use of chest tubes. When there is an accumulation of positive pressure in the chest cavity (where it should normally be negative pressure between pleurae, a patient will require chest drainage. Chest tubes may be inserted to drain body fluids or to facilitate the re-expansion of a lung. It is important for the clinician to determine the most appropriate tube size to use prior to intubation. The position of the chest tube is related to the function that the chest tube performs. When managing the care of patients who have chest tubes it is important to fully understand what to do in case problems arise. It is also important to be able to assess when the chest tube is ready to be discontinued. Nurses and other healthcare professionals who are responsible for the safe delivery of care should be knowledgeable about respiratory pathophysiology, signs of respiratory compromise, and the care and management of interventions that may be utilized to ensure adequate respiration.

  2. Treatment of Snoring with a Nasopharyngeal Airway Tube

    Directory of Open Access Journals (Sweden)

    Macario Camacho

    2016-01-01

    Full Text Available Objective. To study the feasibility of a standard nasopharyngeal airway tube (NPAT as treatment for snoring. Methods. An obese 35-year-old man, who is a chronic, heroic snorer, used NPATs while (1 the patient’s bedpartner scored the snoring and (2 the patient recorded himself with the smartphone snoring app “Quit Snoring.” Baseline snoring was 8–10/10 (10 = snoring that could be heard through a closed door and interrupted the bedpartner’s sleep to the point where they would sometimes have to sleep separately and 60–200 snores/hr. Several standard NPATs were tested, consisting of soft polyvinyl chloride material raging between 24- and 36-French (Fr tubes. Results. The 24 Fr tube did not abate snoring. The 26 Fr tube was able to abate the snoring sound most of the night (smartphone app: 11.4 snores/hr, bedpartner VAS = 2/10. The 28 and 30 Fr tubes abated the snoring sound the entire time worn (smartphone app: 0 snores, bedpartner VAS 0/10 but could not be tolerated more than 2.5 hours. The tube of 36 Fr size could not be inserted, despite several attempts bilaterally. Conclusion. Appropriately sized nasopharyngeal airway tubes may abate the snoring sound; however, as in this patient, they may be too painful and intolerable for daily use.

  3. Device for the selective positioning of a component on a tube plate

    International Nuclear Information System (INIS)

    1974-01-01

    The invention relates to a device for the selective positioning of a component on a tube plate. It particularly applies to the positioning of a guide tube head successively opposite all the tubes of the tube bundle of a nuclear reactor steam generator. The large number of tubes in the tube bundle of the steam generator in a pressure water nuclear power station must be checked periodically for any likely corrosion. This check is effected with a Foucault current probe which is inserted in each tube in turn and is connected to a probe signal processing unit. The probe is placed in a flexible guide tube brought in turn in front of each tube of the bundle to be checked. The invention concerns a device to move the opening of a tube guide for a Foucault current detector over the entire surface of the tube plate, thereby providing access to all the tubes whilst limiting the interventions to a single positioning and a single withdrawal of the apparatus for testing all the bundle. Between the two interventions at the beginning and end of the operation, all displacements are remote controlled from outside the dangerous radioacive area [fr

  4. Helically coiled tube heat exchanger

    International Nuclear Information System (INIS)

    Harris, A.M.

    1981-01-01

    In a heat exchanger such as a steam generator for a nuclear reactor, two or more bundles of helically coiled tubes are arranged in series with the tubes in each bundle integrally continuing through the tube bundles arranged in series therewith. Pitch values for the tubing in any pair of tube bundles, taken transverse to the path of the reactor coolant flow about the tubes, are selected as a ratio of two unequal integers to permit efficient operation of each tube bundle while maintaining the various tube bundles of the heat exchanger within a compact envelope. Preferably, the helix angle and tube pitch parallel to the path of coolant flow are constant for all tubes in a single bundle so that the tubes are of approximately the same length within each bundle

  5. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1982-04-01

    The performance of steam generator tubes in water-cooled nuclear power reactors has been reviewed for 1980. Tube defects occurred at 38% of the 97 reactors surveyed. This is a marginal improvement over 1979 when defects occurred at 41% of the reactors. The number of failed tubes was also lower, 0.14% of the tubes in service in 1980 compared with 0.20% of those in service in 1979. Analysis of the causes of these failures indicates that stress corrosion cracking was the leading failure mechanism. Reactors that used all-volatile treatment of secondary water, with or without full-flow condensate demineralization since start-up showed the lowest incidence of corrosion-related defects

  6. X-ray tube

    International Nuclear Information System (INIS)

    Webley, R.S.

    1975-01-01

    The object of the invention described is to provide an X-ray tube providing a scanned X-ray output which does not require a scanned electron beam. This is obtained by an X-ray tube including an anode which is rotatable about an axis, and a source of a beam of energy, for example an electron beam, arranged to impinge on a surface of the anode to generate X-radiation substantially at the region of incidence on the anode surface. The anode is rotatable about the axis to move the region of incidence over the surface. The anode is so shaped that the rotation causes the region of incidence to move in a predetermined manner relative to fixed parts of the tube so that the generated X-radiation is scanned in a predetermined manner relative to the tube. (UK)

  7. Fuel assembly guide tube

    International Nuclear Information System (INIS)

    Jabsen, F.S.

    1979-01-01

    This invention is directed toward a nuclear fuel assembly guide tube arrangement which restrains spacer grid movement due to coolant flow and which offers secondary means for supporting a fuel assembly during handling and transfer operations

  8. Bull Moose Tube Company

    Science.gov (United States)

    The EPA is providing notice of a proposed Administrative Penalty Assessment against the Bull Moose Tube Company, a business located at 1819 Clarkson Road, Chesterfield, MO, 63017, for alleged violations at the facility located at 406 East Industrial Drive,

  9. Tracheostomy tube - eating

    Science.gov (United States)

    Trach - eating ... take your first bites. Certain factors may make eating or swallowing harder, such as: Changes in the ... easier to swallow. Suction the tracheostomy tube before eating. This will keep you from coughing while eating, ...

  10. Estimation of optimal nasotracheal tube depth in adult patients.

    Science.gov (United States)

    Ji, Sung-Mi

    2017-12-01

    The aim of this study was to estimate the optimal depth of nasotracheal tube placement. We enrolled 110 patients scheduled to undergo oral and maxillofacial surgery, requiring nasotracheal intubation. After intubation, the depth of tube insertion was measured. The neck circumference and distances from nares to tragus, tragus to angle of the mandible, and angle of the mandible to sternal notch were measured. To estimate optimal tube depth, correlation and regression analyses were performed using clinical and anthropometric parameters. The mean tube depth was 28.9 ± 1.3 cm in men (n = 62), and 26.6 ± 1.5 cm in women (n = 48). Tube depth significantly correlated with height (r = 0.735, P < 0.001). Distances from nares to tragus, tragus to angle of the mandible, and angle of the mandible to sternal notch correlated with depth of the endotracheal tube (r = 0.363, r = 0.362, and r = 0.546, P < 0.05). The tube depth also correlated with the sum of these distances (r = 0.646, P < 0.001). We devised the following formula for estimating tube depth: 19.856 + 0.267 × sum of the three distances (R 2 = 0.432, P < 0.001). The optimal tube depth for nasotracheally intubated adult patients correlated with height and sum of the distances from nares to tragus, tragus to angle of the mandible, and angle of the mandible to sternal notch. The proposed equation would be a useful guide to determine optimal nasotracheal tube placement.

  11. Streak tube development

    International Nuclear Information System (INIS)

    Hinrichs, C.K.; Estrella, R.M.

    1979-01-01

    A research program for the development of a high-speed, high-resolution streak image tube is described. This is one task in the development of a streak camera system with digital electronic readout, whose primary application is for diagnostics in underground nuclear testing. This program is concerned with the development of a high-resolution streak image tube compatible with x-ray input and electronic digital output. The tube must be capable of time resolution down to 100 psec and spatial resolution to provide greater than 1000 resolution elements across the cathode (much greater than presently available). Another objective is to develop the capability to make design changes in tube configurations to meet different experimental requirements. A demountable prototype streak tube was constructed, mounted on an optical bench, and placed in a vacuum system. Initial measurements of the tube resolution with an undeflected image show a resolution of 32 line pairs per millimeter over a cathode diameter of one inch, which is consistent with the predictions of the computer simulations. With the initial set of unoptmized deflection plates, the resolution pattern appeared to remain unchanged for static deflections of +- 1/2-inch, a total streak length of one inch, also consistent with the computer simulations. A passively mode-locked frequency-doubled dye laser is being developed as an ultraviolet pulsed light source to measure dynamic tube resolution during streaking. A sweep circuit to provide the deflection voltage in the prototype tube has been designed and constructed and provides a relatively linear ramp voltage with ramp durations adjustable between 10 and 1000 nsec

  12. Researching YouTube

    OpenAIRE

    Arthurs, Jane; Drakopoulou, Sophia; Gandini, Alessandro

    2018-01-01

    ‘Researching YouTube’ introduces the special issue of Convergence which arose out of an international academic conference on YouTube that was held in London at Middlesex University in September 2016. The conference aimed to generate a robust overview of YouTube’s changing character and significance after its first ten years of development by creating a productive dialogue between speakers from different disciplines and cultures, and between YouTube-specific research and wider debates in media...

  13. Tubing crimping pliers

    Science.gov (United States)

    Lindholm, G.T.

    1981-02-27

    The disclosure relates to pliers and more particularly to pliers for crimping two or more pieces of copper tubing together prior to their being permanently joined by brazing, soldering or the like. A die containing spring-loaded pins rotates within a cammed ring in the head of the pliers. As the die rotates, the pins force a crimp on tubing held within the pliers.

  14. Tube spacer grid for a heat-exchanger tube bundle

    International Nuclear Information System (INIS)

    Scheidl, H.

    1976-01-01

    A tube spacer grid for a heat-exchanger tube bundle is formed by an annular grid frame having a groove formed in its inner surface in which the interspaced grid bars have their ends positioned and held in interspaced relationship by short sections of tubes passed through holes axially formed in the grid frame so that the tubes are positioned between the ends of the grid bars in the grooves. The tube sections may be cut from the same tubes used to form the tube bundle. 5 claims, 3 drawing figures

  15. Speaking Tracheostomy Tube and Modified Mouthstick Stylus in a Ventilator-Dependent Patient with Spinal Cord Injury

    OpenAIRE

    Mitate, Eiji; Kubota, Kensuke; Ueki, Kenji; Inoue, Rumi; Inoue, Ryosuke; Momii, Kenta; Sugimori, Hiroshi; Maehara, Yoshihiko; Nakamura, Seiji

    2015-01-01

    Communication is a serious problem for patients with ventilator-dependent tetraplegia. A 73-year-old man was presented at the emergency room in cardiopulmonary arrest after falling from a height of 2 m. After successful resuscitation, fractures of the cervical spine and cervical spinal cord injury were found. Due to paralysis of the respiratory muscles, a mechanical ventilator with a tracheostomy tube was required. First, a cuffed tracheostomy tube and a speaking tracheostomy tube were insert...

  16. Insertable fluid flow passage bridgepiece and method

    Science.gov (United States)

    Jones, Daniel O.

    2000-01-01

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  17. Utility Bill Insert for Wastewater Services

    Science.gov (United States)

    Intended for use by wastewater and water supply utilities, one side of the utility bill insert has information for customers that discharge to sanitary sewer systems; the other side is for customers with septic systems.

  18. HB+ inserted into the CMS Solenoid

    CERN Multimedia

    Tejinder S. Virdee, CERN

    2006-01-01

    The first half of the barrel hadron calorimeter (HB+) has been inserted into the superconducting solenoid of CMS, in preparation for the magnet test and cosmic challenge. The operation went smoothly, lasting a couple of days.

  19. Bulkhead insert for an internal combustion engine

    Science.gov (United States)

    Maki, Clifford E.; Chottiner, Jeffrey Eliot; Williams, Rick L.; Thibault, Mark W.; Ervin, James Douglas; Boileau, James Maurice; McKeough, Bryan

    2017-08-01

    An engine includes a cylinder block defining at least one main bearing bulkhead adjacent to a cylinder, and a crankshaft rotatably housed within the block by a main bearing. A bulkhead insert has a cap portion, and an insert portion provided within the bulkhead. The insert portion has having first and second end regions connected by first and second straps. Each strap having a flanged beam cross section. The first and second ends of the insert portion are configured to connect a main bearing cap column to a cylinder head column. Each of the first and second end regions define at least one protrusion having a surface substantially normal to engine combustion and reactive loads. The cap portion is configured to mate with the first end region at the main bearing cap column and support the main bearing.

  20. Chronic insertional Achilles tendinopathy: surgical outcomes

    OpenAIRE

    Oshri, Yael; Palmanovich, Ezequiel; Brin, Yaron Shagra; Karpf, Ronen; Massarwe, Sabri; Kish, Benny; Nyska, Meir

    2012-01-01

    Background and objective: insertional Achilles tendinopathy is a common condition among athletes and joggers. One fifth of the injuries involves the insertion of the tendon. The etiology is either due to mechanical overuse related to sports activity, or a systemic inflammatory disease. The clinical appearance includes pain and movement restriction. The primary treatment is conservative. The surgery referred to in this study (Calcaneal Osteotomy) is performed by decompression of the posterior ...

  1. Z-2 Threaded Insert Design and Testing

    Science.gov (United States)

    Ross, Amy; Rhodes, Richard; Jones, Robert J.; Graziosi, David; Ferl, Jinny; Sweeny, Mitch; Scarborough, Stephen

    2016-01-01

    NASA's Z-2 prototype space suit contains several components fabricated from an advanced hybrid composite laminate consisting of IM10 carbon fiber and fiber glass. One requirement was to have removable, replaceable helicoil inserts to which other suit components would be fastened. An approach utilizing bonded in inserts with helicoils inside of them was implemented. During initial assembly, cracking sounds were heard followed by the lifting of one of the blind inserts out of its hole when the screws were torqued. A failure investigation was initiated to understand the mechanism of the failure. Ultimately, it was determined that the pre-tension caused by torqueing the fasteners is a much larger force than induced from the pressure loads of the suit which was not considered in the insert design. Bolt tension is determined by dividing the torque on the screw by a k value multiplied by the thread diameter of the bolt. The k value is a factor that accounts for friction in the system. A common value used for k for a non-lubricated screw is 0.2. The k value can go down by as much as 0.1 if the screw is lubricated which means for the same torque, a much larger tension could be placed on the bolt and insert. This paper summarizes the failure investigation that was performed to identify the root cause of the suit failure and details how the insert design was modified to resist a higher pull out tension.

  2. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home >> NEI YouTube Videos >> NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract ...

  3. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home » NEI YouTube Videos » NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract ...

  4. Fallopian Tube Herniation: An Unusual Complication of Surgical Drain

    OpenAIRE

    Sharma, Lipi; Singh, Alpana; Bhaskaran, Sruthi; Radhika, A. G.; Radhakrishnan, Gita

    2012-01-01

    Background. Surgical drains have been used since time immemorial, but their use is not without complications. By presenting this case we aim to describe an uncommon complication of herniation of fallopian tube following the simple procedure of surgical drain removal. Case Presentation. This case describes a 23-year G2P1L1 who underwent an emergency cesarean section for obstructed labor with intraperitoneal drain insertion. The patient had an uneventful postoperative period, drain was removed ...

  5. Needle Revision With 5-fluorouracil for the Treatment of Ahmed Glaucoma Valve Filtering Blebs: 5-Fluoruracil Needling Revision can be a Useful and Safe Tool in the Management of Failing Ahmed Glaucoma Valve Filtering Blebs.

    Science.gov (United States)

    Quaranta, Luciano; Floriani, Irene; Hollander, Lital; Poli, Davide; Katsanos, Andreas; Konstas, Anastasios G P

    2016-04-01

    To determine the outcome of needling with adjunctive 5-fluorouracil (5-FU) in patients with a failing Ahmed glaucoma valve (AGV) implant, and to identify predictors of long-term intraocular pressure (IOP) control. A prospective observational study was performed on consecutive patients with medically uncontrolled primary open-angle glaucoma (POAG) with AGV encapsulation or fibrosis and inadequate IOP control. Bleb needling with 5-FU injection (0.1 mL of 50 mg/mL) was performed at the slit-lamp. Patients were examined 1 week following the needling, and then at months 1, 3, and 6. Subsequent follow-up visits were scheduled at 6-month intervals for at least 2 years. Needling with 5-FU was repeated no more than twice during the first 3 months of the follow-up. Procedure outcome was determined on the basis of the recorded IOP levels. Thirty-six patients with an encapsulated or fibrotic AGV underwent 67procedures (mean 1.86 ± 0.83). Complete success, defined as IOP ≤ 18 mm Hg without medications, was obtained in 25% at 24 months of observation. The cumulative proportion of cases achieving either qualified (ie, IOP ≤ 18 mm Hg with medications) or complete success at 24 months of observation was 72.2%. In a univariate Cox proportional hazards model, age was the only variable that independently influenced the risk of failing 5-FU needling revision. Fourteen eyes (38.8%) had a documented complication. Needling over the plate of an AGV supplemented with 5-FU is an effective and safe choice in a significant proportion of POAG patients with elevated IOP due to encapsulation or fibrosis.

  6. Replacement of Mushroom Cage Gastrostomy Tube Using a Modified Technique to Allow Percutaneous Replacement with an Endoscopic Tube in Patients with Amyotrophic Lateral Sclerosis

    International Nuclear Information System (INIS)

    Ammar, Thoraya; Rio, Alan; Ampong, Mary Ann; Sidhu, Paul S.

    2010-01-01

    Radiologic inserted gastrostomy (RIG) is the preferred method in our institution for enteral feeding in amyotrophic lateral sclerosis (ALS). Skin-level primary-placed mushroom cage gastrostomy tubes become tight with weight gain. We describe a minimally invasive radiologic technique for replacing mushroom gastrostomy tubes with endoscopic mushroom cage tubes in ALS. All patients with ALS who underwent replacement of a RIG tube were included. Patients were selected for a modified replacement when the tube length of the primary placed RIG tube was insufficient to allow like-for-like replacement. Replacement was performed under local anesthetic and fluoroscopic guidance according to a preset technique, with modification of an endoscopic mushroom cage gastrostomy tube to allow percutaneous placement. Assessment of the success, safety, and durability of the modified technique was undertaken. Over a 60-month period, 104 primary placement mushroom cage tubes in ALS were performed. A total of 20 (19.2%) of 104 patients had a replacement tube positioned, 10 (9.6%) of 104 with the modified technique (male n = 4, female n = 6, mean age 65.5 years, range 48-85 years). All tubes were successfully replaced using this modified technique, with two minor complications (superficial wound infection and minor hemorrhage). The mean length of time of tube durability was 158.5 days (range 6-471 days), with all but one patient dying with a functional tube in place. We have devised a modification to allow percutaneous replacement of mushroom cage gastrostomy feeding tubes with minimal compromise to ALS patients. This technique allows tube replacement under local anesthetic, without the need for sedation, an important consideration in ALS.

  7. Insertion of Balloon Retained Gastrostomy Buttons: A 5-Year Retrospective Review of 260 Patients

    International Nuclear Information System (INIS)

    Power, Sarah; Kavanagh, Liam N.; Shields, Mary C.; Given, Mark F.; Keeling, Aoife N.; McGrath, Frank P.; Lee, Michael J.

    2013-01-01

    Radiologically inserted gastrostomy (RIG) is an established way of maintaining enteral nutrition in patients who cannot maintain nutrition orally. The purpose of this study was to evaluate the safety and efficacy of primary placement of a wide bore button gastrostomy in a large, varied patient population through retrospective review. All patients who underwent gastrostomy placement from January 1, 2004 to January 1, 2009 were identified. 18-Fr gastrostomy buttons (MIC-Key G) were inserted in the majority. Follow-up ranged from 6 months to 4.5 years. A total of 260 patients (M:F 140:120, average age 59.2 years) underwent gastrostomy during the study period. Overall success rate for RIG placement was 99.6 %, with success rate of 95.3 % for primary button insertion. Indications included neurological disorders (70 %), esophageal/head and neck malignancy (21 %), and other indications (9 %). Major and minor complication rates were 1.2 and 12.8 %, respectively. Thirty-day mortality rate was 6.8 %. One third of patients underwent gastrostomy reinsertion during the study period, the main indication for which was inadvertent catheter removal. Patency rate was high at 99.5 %. The maximum number of procedures in any patient was 8 (n = 2), and the average tube dwell time was 125 days. Primary radiological insertion of a wide bore button gastrostomy is a safe technique, with high success rate, high patency rate, and low major complication rate. We believe that it is feasible to attempt button gastrostomy placement in all patients, once tract length is within limits of tube length. If difficulty is encountered, then a standard tube may simply be placed instead.

  8. Insertion of Balloon Retained Gastrostomy Buttons: A 5-Year Retrospective Review of 260 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Power, Sarah, E-mail: sarahpower28@yahoo.co.uk; Kavanagh, Liam N.; Shields, Mary C.; Given, Mark F.; Keeling, Aoife N.; McGrath, Frank P.; Lee, Michael J., E-mail: mlee@rcsi.ie [Beaumont Hospital, Department of Radiology (Ireland)

    2013-04-15

    Radiologically inserted gastrostomy (RIG) is an established way of maintaining enteral nutrition in patients who cannot maintain nutrition orally. The purpose of this study was to evaluate the safety and efficacy of primary placement of a wide bore button gastrostomy in a large, varied patient population through retrospective review. All patients who underwent gastrostomy placement from January 1, 2004 to January 1, 2009 were identified. 18-Fr gastrostomy buttons (MIC-Key G) were inserted in the majority. Follow-up ranged from 6 months to 4.5 years. A total of 260 patients (M:F 140:120, average age 59.2 years) underwent gastrostomy during the study period. Overall success rate for RIG placement was 99.6 %, with success rate of 95.3 % for primary button insertion. Indications included neurological disorders (70 %), esophageal/head and neck malignancy (21 %), and other indications (9 %). Major and minor complication rates were 1.2 and 12.8 %, respectively. Thirty-day mortality rate was 6.8 %. One third of patients underwent gastrostomy reinsertion during the study period, the main indication for which was inadvertent catheter removal. Patency rate was high at 99.5 %. The maximum number of procedures in any patient was 8 (n = 2), and the average tube dwell time was 125 days. Primary radiological insertion of a wide bore button gastrostomy is a safe technique, with high success rate, high patency rate, and low major complication rate. We believe that it is feasible to attempt button gastrostomy placement in all patients, once tract length is within limits of tube length. If difficulty is encountered, then a standard tube may simply be placed instead.

  9. The effects of an inserted linear carbon chain on the vibration of a carbon nanotube

    International Nuclear Information System (INIS)

    Hu, Z L; Guo, X M; Ru, C Q

    2007-01-01

    An elastic string-elastic shell model is developed to study the coupled vibration of a carbon nanowire made of a linear carbon chain (C-chain) inserted inside a carbon nanotube (CNT). It is shown that the vibration of the inserted C-chain is coupled with vibration of the CNT only for vibration modes with circumferential wavenumber n = 1. In other cases, such as axisymmetric modes (n = 0) or higher-order vibration modes with n≥2, total resultant van der Waals (vdW) force acting on the C-chain due to the innermost tube always vanishes, and therefore vibration of the CNT does not cause vibration of the inserted C-chain, although the existence of the C-chain does have an effect on the vibration of the CNT through the chain-CNT vdW forces acting on the innermost tube. The present model predicts that non-coaxial vibration between the C-chain and the innermost tube does not occur due to negligible bending rigidity of the C-chain. In addition, it is found that the C-chain has most significant effect on the lowest frequency associated with the radial vibration mode for circumferential wavenumber 2 (n = 2). In particular, the effect of the C-chain on the axisymmetric radial breathing frequencies (n = 0) predicted by the present model is found to be in reasonable agreement with known experimental and modeling results available in the literature. The present work offers systematic modeling results on the effects of an inserted C-chain on the vibration of CNTs

  10. SOLVENTLESS MIGRATORY-INSERTION REACTIONS OF ...

    African Journals Online (AJOL)

    Preferred Customer

    The product formed by reaction of an alkyl or aryl cyclopentadienyl metal carbonyl .... (as also observed from the NMR tube experiments) that the solventless reaction between ... As can be seen from Figure 3, the reaction rate in the melt.

  11. Treating mediastinoesophageal fistula with covered stent through nasal esophagus drainage tube

    International Nuclear Information System (INIS)

    Han Xinwei; Wu Gang; Li Yongdong; Ma Nan; Wang Yanli; Gao Xuemei

    2005-01-01

    Objective: To investigate the value of treating mediastinoesophageal fistula with covered stent through nasal esophagus drainage tube. Methods: Ten patients with mediastinoesophageal fistula were treated by 5F catheter inserting into the abscess cavities through nasal esophageal fistula, with stent placement in the esophagus. The abscess cavities were washed and angiograghied through drainage tube and the sites of the drainage tube were adjusted in time until withdrawal of the tube. Results: The drainage tubes were pulled out within 10-25 days with disappearance of the abscess cavities and normal diet intake without difficulty. Conclusions: Treating mediastinoesophageal fistula with covered stent through nasal esophagus drainage tube is safe, microinvasive economic and acceptable, worth to be recommended. (authors)

  12. Tube plug removal machine

    International Nuclear Information System (INIS)

    Hawkins, P.J.

    1987-01-01

    In a nuclear steam generator wherein some faulty tubes have been isolated by mechanical plugging, to remove a selected plug without damaging the associated tube, a plug removal machine is used. The machine drills into a plug portion with a tap drill bit having a drill portion a tap portion and a threaded portion, engaging that plug portion with the threaded portion after the drilled hole has been threaded by the tap portion thereof, and removing a portion of the plug in the tube with a counterbore drill bit mounted concentrically about the tap drill bit. A trip pin and trip spline disengage the tap drill bit from the motor. The counterbore drill bit is thereafter self-centered with respect to the tube and plug about the now stationary tap drill bit. After a portion of the plug has been removed by the counterbore drill bit, pulling on the top drill bit by grippers on slots will remove the remaining plug portion from the tube. (author)

  13. Categorising YouTube

    Directory of Open Access Journals (Sweden)

    Thomas Mosebo Simonsen

    2011-09-01

    Full Text Available This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC of YouTube. The article investigates the construction of navigationprocesses on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within the interacting relationship of new and old genres are discussed. It is argued that the utility of a conventional categorical system is primarily of analytical and theoretical interest rather than as a practical instrument.

  14. Measuring of tube expansion

    International Nuclear Information System (INIS)

    Vogeleer, J. P.

    1985-01-01

    The expansion of the primary tubes or sleeves of the steam generator of a nuclear reactor plant are measured while the tubes or sleeves are being expanded. A primary tube or sleeve is expanded by high pressure of water which flows through a channel in an expander body. The water is supplied through an elongated conductor and is introduced through a connector on the shank connected to the conductor at its outer end. A wire extends through the mandrel and through the conductor to the end of the connector. At its inner end the wire is connected to a tapered pin which is subject to counteracting forces produced by the pressure of the water. The force on the side where the wire is connected to the conductor is smaller than on the opposite side. The tapered pin is moved in the direction of the higher force and extrudes the wire outwardly of the conductor. The tapered surface of the tapered pin engages transverse captive plungers which are maintained in engagement with the expanding tube or sleeve as they are moved outwardly by the tapered pin. The wire and the connector extend out of the generator and, at its outer end, the wire is connected to an indicator which measures the extent to which the wire is moved by the tapered pin, thus measuring the expansion of the tube or sleeve as it progresses

  15. Enhancement of acoustical performance of hollow tube sound absorber

    International Nuclear Information System (INIS)

    Putra, Azma; Khair, Fazlin Abd; Nor, Mohd Jailani Mohd

    2016-01-01

    This paper presents acoustical performance of hollow structures utilizing the recycled lollipop sticks as acoustic absorbers. The hollow cross section of the structures is arranged facing the sound incidence. The effects of different length of the sticks and air gap on the acoustical performance are studied. The absorption coefficient was measured using impedance tube method. Here it is found that improvement on the sound absorption performance is achieved by introducing natural kapok fiber inserted into the void between the hollow structures. Results reveal that by inserting the kapok fibers, both the absorption bandwidth and the absorption coefficient increase. For test sample backed by a rigid surface, best performance of sound absorption is obtained for fibers inserted at the front and back sides of the absorber. And for the case of test sample with air gap, this is achieved for fibers introduced only at the back side of the absorber.

  16. Enhancement of acoustical performance of hollow tube sound absorber

    Energy Technology Data Exchange (ETDEWEB)

    Putra, Azma, E-mail: azma.putra@utem.edu.my; Khair, Fazlin Abd, E-mail: fazlinabdkhair@student.utem.edu.my; Nor, Mohd Jailani Mohd, E-mail: jai@utem.edu.my [Centre for Advanced Research on Energy, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, Durian Tunggal Melaka 76100 Malaysia (Malaysia)

    2016-03-29

    This paper presents acoustical performance of hollow structures utilizing the recycled lollipop sticks as acoustic absorbers. The hollow cross section of the structures is arranged facing the sound incidence. The effects of different length of the sticks and air gap on the acoustical performance are studied. The absorption coefficient was measured using impedance tube method. Here it is found that improvement on the sound absorption performance is achieved by introducing natural kapok fiber inserted into the void between the hollow structures. Results reveal that by inserting the kapok fibers, both the absorption bandwidth and the absorption coefficient increase. For test sample backed by a rigid surface, best performance of sound absorption is obtained for fibers inserted at the front and back sides of the absorber. And for the case of test sample with air gap, this is achieved for fibers introduced only at the back side of the absorber.

  17. Comparison of endoscopic Nd:YAG laser therapy and oesophageal tube in palliation of oesophagogastric malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Hahl, J.; Salo, T.; Ovaska, J.; Haapiainen, R.; Kalima, T.; Schroeder, T. (Helsinki Univ. Central Hospital (Finland). Meilahti Clinic)

    1991-01-01

    The clinical results of 96 patients with upper gastrointestinal malignancy have been evaluated retrospectively. 69 patients with a mean age of 72 years (35 men and 34 women) were treated with endoscopic laser therapy, and 27 patients with a mean age of 67 years (16 men and 11 women) with insertion of an oesophageal tube. After laser therapy the bulk of the tumour was reduced in 87%, and in 55% clear signs of relieved dysphagia were seen. The insertion of an esophageal tube was successful in 89%. In the laser group no fatal complications occurred, and the overall complication risk was 8.7%. The first-year survival in all laser patients was 12%, and in patients with impassable tumour stenosis the survival was 6%. The mortality related to the insertion of an oesophageal tube was 11%, and complications occurred in 48% of the patients. The first-year survival of the tube group was nil. It is concluded that endoscopic laser therapy and insertion of oesophageal tube are both effective methods in palliation of oesophagogastric malignancy, but the mortality and risk for complications were markedly lower after laser therapy. 20 refs., 1 fig., 3 tabs.

  18. Method and apparatus for testing closed-end tubes in heat exchangers of nuclear reactors and the like

    International Nuclear Information System (INIS)

    Seyd, G.; Bergbauer, A.; Paulsen, U.

    1975-01-01

    A description is given of a test stopper which is insertable into a tube closed at one end for testing the tightness of the tube with a fluid under pressure, the tube being in a heat exchanger of a nuclear reactor or the like. The test stopper includes a tubular outer jacket that is expandable outwardly to tightly seat the stopper in the tube. The stopper also has front and back end-face members joined to the ends of the outer jacket to define a closed space within the jacket. With the stopper inserted into the tube, the front end-face member and the closed end portion of the tube define a closed inner region of the tube. An inner tubular member, disposed within the outer jacket, partitions the closed space within the jacket into an annular outer chamber and a cylindrical inner chamber. A pressure-fluid supply selectively supplies fluid to the chambers. The outer jacket expands in response to fluid admitted to the annular chamber and the front end-face member has a through bore to admit fluid under pressure to the inner region of the tube. A method of testing of such a tube with a fluid under pressure includes inserting the test stopper into the tube and then expanding the outer jacket of the stopper to seat the stopper firmly in the tube. A fluid under pressure is directed through the stopper and into the closed region defined by the front end-face member of the stopper and the closed end portion of the tube. The pressure of the fluid introduced into this closed region is monitored for detecting a leak in the closed-end tube

  19. Comparison of Ahmed glaucoma valve implantation and trabeculectomy for glaucoma: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Tan HaiBo

    Full Text Available To compare the efficacy and safety of Ahmed glaucoma valve implantation (AGV with trabeculectomy in the management of glaucoma patients.A comprehensive literature search (PubMed, Embase, Google, and the Cochrane library was performed, including a systematic review with meta-analysis of controlled clinical trials comparing AGV versus trabeculectomy. Efficacy estimates were the weighted mean differences (WMDs for the percentage intraocular pressure reduction (IOPR % from baseline to end-point, the reduction in glaucoma medications, and the odds ratios (ORs for complete and qualified success rates. Safety estimates were the relative risks (RRs for adverse events. All outcomes were reported with a 95% confidence interval (CI. Statistical analysis was performed using the RevMan 5.0 software.Six controlled clinical trials were included in this meta-analysis. There was no significant difference between the AGV and trabeculectomy in the IOPR% (WMD = -3.04, 95% CI: -8.36- 2.26; P = 0.26. The pooled ORs comparing AGV with trabeculectomy were 0.46 (0.22, 0.99 for the complete success rate (P = 0.05 and 0.97 (0.78-1.20 for the quantified success rate (P = 0.76. No significant difference in the reduction in glaucoma medicines was observed (WMD = 0.24; 95% CI: -0.27-0.76; P = 0.35. AGV was found to be associated with a significantly lower frequency of all adverse events (RR = 0.71; 95%CI: 1.14-0.97; p = 0.001 than trabeculectomy, while the most common complications did not differ significantly (all p> 0.05.AGV was equivalent to trabeculectomy in reducing the IOP, the number of glaucoma medications, success rates, and rates of the most common complications. However, AGV was associated with a significantly lower frequency of overall adverse events.

  20. Comparison of Generalized Estimating Equations and Quadratic Inference Functions in superior versus inferior Ahmed Glaucoma Valve implantation

    Directory of Open Access Journals (Sweden)

    Razieh Khajeh-Kazemi

    2011-01-01

    Full Text Available Background: The celebrated generalized estimating equations (GEE approach is often used in longitudinal data analysis While this method behaves robustly against misspecification of the working correlation structure, it has some limitations on efficacy of estimators, goodness-of-fit tests and model selection criteria The quadratic inference functions (QIF is a new statistical methodology that overcomes these limitations Methods : We administered the use of QIF and GEE in comparing the superior and inferior Ahmed glaucoma valve (AGV implantation, while our focus was on the efficiency of estimation and using model selection criteria, we compared the effect of implant location on intraocular pressure (IOP in refractory glaucoma patients We modeled the relationship between IOP and implant location, patient′s sex and age, best corrected visual acuity, history of cataract surgery, preoperative IOP and months after surgery with assuming unstructured working correlation Results : 63 eyes of 63 patients were included in this study, 28 eyes in inferior group and 35 eyes in superior group The GEE analysis revealed that preoperative IOP has a significant effect on IOP (p = 0 011 However, QIF showed that preoperative IOP, months after surgery and squared months are significantly associated with IOP after surgery (p < 0 05 Overall, estimates from QIF are more efficient than GEE (RE = 1 272 Conclusions : In the case of unstructured working correlation, the QIF is more efficient than GEE There were no considerable difference between these locations, our results confirmed previously published works which mentioned it is better that glaucoma patients undergo superior AGV implantation

  1. Comparison of Ahmed glaucoma valve implantation and trabeculectomy for glaucoma: a systematic review and meta-analysis.

    Science.gov (United States)

    HaiBo, Tan; Xin, Kang; ShiHeng, Lu; Lin, Liu

    2015-01-01

    To compare the efficacy and safety of Ahmed glaucoma valve implantation (AGV) with trabeculectomy in the management of glaucoma patients. A comprehensive literature search (PubMed, Embase, Google, and the Cochrane library) was performed, including a systematic review with meta-analysis of controlled clinical trials comparing AGV versus trabeculectomy. Efficacy estimates were the weighted mean differences (WMDs) for the percentage intraocular pressure reduction (IOPR %) from baseline to end-point, the reduction in glaucoma medications, and the odds ratios (ORs) for complete and qualified success rates. Safety estimates were the relative risks (RRs) for adverse events. All outcomes were reported with a 95% confidence interval (CI). Statistical analysis was performed using the RevMan 5.0 software. Six controlled clinical trials were included in this meta-analysis. There was no significant difference between the AGV and trabeculectomy in the IOPR% (WMD = -3.04, 95% CI: -8.36- 2.26; P = 0.26). The pooled ORs comparing AGV with trabeculectomy were 0.46 (0.22, 0.99) for the complete success rate (P = 0.05) and 0.97 (0.78-1.20) for the quantified success rate (P = 0.76). No significant difference in the reduction in glaucoma medicines was observed (WMD = 0.24; 95% CI: -0.27-0.76; P = 0.35). AGV was found to be associated with a significantly lower frequency of all adverse events (RR = 0.71; 95%CI: 1.14-0.97; p = 0.001) than trabeculectomy, while the most common complications did not differ significantly (all p> 0.05). AGV was equivalent to trabeculectomy in reducing the IOP, the number of glaucoma medications, success rates, and rates of the most common complications. However, AGV was associated with a significantly lower frequency of overall adverse events.

  2. Pars Plana-Modified versus Conventional Ahmed Glaucoma Valve in Patients Undergoing Penetrating Keratoplasty: A Prospective Comparative Randomized Study.

    Science.gov (United States)

    Parihar, Jitendra Kumar Singh; Jain, Vaibhav Kumar; Kaushik, Jaya; Mishra, Avinash

    2017-03-01

    To compare the outcome of pars-plana-modified Ahmed glaucoma valve (AGV) versus limbal-based conventional AGV into the anterior chamber, in patients undergoing penetrating keratoplasty (PK) for glaucoma with coexisting corneal diseases. In this prospective randomized clinical trial, 58 eyes of 58 patients with glaucoma and coexisting corneal disease were divided into two groups. Group 1 (29 eyes of 29 patients) included patients undergoing limbal-based conventional AGV into the anterior chamber (AC) along-with PK and group 2 (29 eyes of 29 patients) included those undergoing pars-plana-modified AGV along-with PK. Outcome measures included corneal graft clarity, intraocular pressure (IOP), number of antiglaucoma medications, and postoperative complications. Patients were followed up for a minimum period of 2 years. Out of 58 eyes (58 patients), 50 eyes (50 patients: 25 eyes of 25 patients each in group 1 and group 2) completed the study and were analyzed. Complete success rate for AGV (group 1: 76%; group 2: 72%; p = 0.842) and corneal graft clarity (group 1: 68%; group 2: 76%; p = 0.081) were comparable between the two groups at 2 years. Graft failure was more in conventional AGV (32%) as compared to pars plana-modified AGV (24%) but not statistically significant (p = 0.078) at 2 years. Though both procedures were comparable in various outcome measures, pars-plana-modified AGV is a viable option for patients undergoing PK, as it provides a relatively better corneal graft survival rate and lesser complications that were associated with conventional AGV.

  3. A prospective comparative study on neovascular glaucoma and non-neovascular refractory glaucoma following Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Li, Zheng; Zhou, Minwen; Wang, Wei; Huang, Wenbin; Chen, Shida; Li, Xingyi; Gao, Xinbo; Zhang, Xiulan

    2014-01-01

    Neovascular glaucoma is a refractory disease, and difficult to manage. The aim of this study was to evaluate the clinical outcomes of Ahmed glaucoma valve implantation (AGVI) in neovascular glaucoma (NVG) and non-NVG patients. This prospective, non-randomized study included 55 eyes of 55 patients with refractory glaucoma; 27 had NVG (NVG group) and 28 had non-NVG (non-NVG group). All of the patients underwent AGVI. The NVG group was adjunctively injected with intravitreal ranibizumab/bevacizumab (IVR/IVB) before AGVI. Intraocular pressure (IOP) was the primary outcome measure in this study. Surgical success rate, number of antiglaucoma medications used, best corrected visual acuity (BCVA), and postoperative complications were analyzed between the groups. All of the patients completed the study (follow-up of 12 months). Kaplan-Meier survival curve analysis indicated that the qualified success rates in the NVG and non-NVG groups at 12 months were 70.5% and 92.9%, respectively; this difference was significant (P = 0.036). The complete success rates in the NVG and non-NVG groups at 12 months were 66.7% and 89.3%, respectively (P = 0.049). Compared with preoperative examinations, the postoperative mean IOP and use of medications were significantly lower at all follow-up time points in both groups (all P glaucoma, but the success rate of surgery was related to the type of refractory glaucoma. The complete and qualified success rates of NVG patient adjunctive anti-vascular endothelial growth factor treatment are still lower than those of non-NVG patients.

  4. Long-term outcomes of uveitic glaucoma treated with Ahmed valve implant in a series of Chinese patients.

    Science.gov (United States)

    Bao, Ning; Jiang, Zheng-Xuan; Coh, Paul; Tao, Li-Ming

    2018-01-01

    To report long-term outcomes of secondary glaucoma due to uveitis treated with Ahmed glaucoma valve (AGV) implantation in a series of Chinese patients. The retrospective study included 67 eyes from 56 patients with uveitic glaucoma who underwent AGV implantation. Success of the treatment was defined as patients achieving intraocular pressure (IOP) levels between 6 and 21 mm Hg with or without additional anti-glaucoma medications and/or a minimum of 20% reduction from baseline IOP. The main outcome measurements included IOP, the number of glaucoma medications at 1, 3, 6, 12, 24, 36, 48 and 60mo after surgery, surgical complications, final best-corrected vision acuity (BCVA), visual field (VF) and retinal nerve fiber layer (RNFL). The mean follow-up was 53.3±8.5 (range 48 to 60)mo. The cumulative probability of success rate was 98.5%, 95.5%, 89.6%, 83.6%, 76.1%, 70.1%, 65.7% and 61.2% at 1, 3, 6, 12, 24, 36, 48 and 60mo, respectively. IOP was reduced from a baseline of 30.8±6.8 to 9.9±4.1, 10.1±4.2, 10.9±3.7, 12.9±4.6, 13.8±3.9, 13.2±4.6, 12.3±3.5 and 13.1±3.7 mm Hg at 1, 3, 6, 12, 24, 36, 48 and 60mo, respectively ( P glaucoma medications was significantly decreased compared with baseline at all time points during the study period ( P glaucoma medications, and preserving vision for patients with uveitic glaucoma.

  5. Ahmed glaucoma valve in uveitic patients with fluocinolone acetonide implant-induced glaucoma: 3-year follow-up.

    Science.gov (United States)

    Kubaisi, Buraa; Maleki, Arash; Ahmed, Aseef; Lamba, Neel; Sahawneh, Haitham; Stephenson, Andrew; Montieth, Alyssa; Topgi, Shobha; Foster, C Stephen

    2018-01-01

    To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) in eyes with noninfectious uveitis that had fluocinolone acetonide intravitreal implant (Retisert™)-induced glaucoma. This retrospective study reviewed the safety and efficacy of AGV implantation in patients with persistently elevated intraocular pressure (IOP) after implantation of a fluocinolone acetonide intravitreal implant at the Massachusetts Eye Research and Surgery Institution between August 2006 and November 2015. Nine patients with 10 uveitic eyes were included in this study, none of which had preexisting glaucoma in the study eye. Mean patient age was 42 years; 6 patients were female and 3 were male. Baseline mean IOP was 30.6 mmHg prior to AGV placement while mean IOP-lowering medications were 2.9. In the treatment groups, there was a statistically significant reduction in post-AGV IOP. IOP was lowest at 1-week after AGV implantation (9.0 mmHg). Nine out of 10 eyes achieved an IOP below target value of 22 mmHg and/or a 20% reduction in IOP from baseline 1 month and 1 year following AGV placement. All other postoperative time points showed all 10 eyes reaching this goal. A statistically significant decrease in IOP-lowering medication was seen at the 1-week, 1-month, and 3-year time points compared to baseline, while a statistically significant increase was seen at the 3-month, 6-month, and 2-year post-AGV time points. No significant change in retinal nerve thickness or visual field analysis was found. AGV is an effective and safe method of treatment in fluocinolone acetonide intravitreal implant-induced glaucoma. High survival rate is expected for at least 3 years.

  6. Changes in Corneal Endothelial Cell after Ahmed Glaucoma Valve Implantation and Trabeculectomy: 1-Year Follow-up.

    Science.gov (United States)

    Kim, Min Su; Kim, Kyoung Nam; Kim, Chang-Sik

    2016-12-01

    To compare changes in corneal endothelial cell density (CECD) after Ahmed glaucoma valve (AGV) implantation and trabeculectomy. Changes in corneal endothelium in patients that underwent AGV implantation or trabeculectomy were prospectively evaluated. Corneal specular microscopy was performed at the central cornea using a non-contact specular microscope before surgery and 6 months and 12 months after surgery. The CECD, hexagonality of the endothelial cells, and the coefficient of variation of the cell areas were compared between the two groups. Forty eyes of 40 patients with AGV implantation and 28 eyes of 28 patients with trabeculectomy were studied. Intraocular pressure in the AGV implantation group was significantly higher than that in the trabeculectomy group ( p < 0.001), but there was no significant difference in other clinical variables between the two groups. In the AGV implantation group, the mean CECD significantly decreased by 9.4% at 6 months and 12.3% at 12 months compared with baseline values (both, p < 0.001), while it decreased by 1.9% at 6 months and 3.2% at 12 months in the trabeculectomy group ( p = 0.027 and p = 0.015, respectively). The changes at 6 months and 12 months in the AGV implantation group were significantly higher than those in the trabeculectomy group ( p = 0.030 and p = 0.027, respectively). In the AGV implantation group, there was a significant decrease in the CECD between baseline and 6 months and between 6 months and 12 months ( p < 0.001 and p = 0.005, respectively). However, in the trabeculectomy group, a significant decrease was observed only between baseline and 6 months ( p = 0.027). Both the AGV implantation group and the trabeculectomy group showed statistically significant decreases in the CECD 1 year after surgery. The decrease in CECD in the AVG implantation group was greater and persisted longer than that in the trabeculectomy group.

  7. Ahmed Versus Baerveldt Glaucoma Drainage Implantation in Patients With Markedly Elevated Intraocular Pressure (≥30 mm Hg).

    Science.gov (United States)

    Resende, Arthur F; Moster, Marlene R; Patel, Neal S; Lee, Daniel; Dhami, Hermandeep; Pro, Michael J; Waisbourd, Michael

    2016-09-01

    Glaucoma patients with markedly elevated intraocular pressure (IOP) are at risk for developing severe hypotony-related complications. The goal of this study was to compare the surgical outcomes of the Ahmed Glaucoma Valve (AGV) and the Baerveldt Glaucoma Implant (BGI) in this patient population. Patients with preoperative IOP≥30 mm Hg were included. Outcome measures were: (1) surgical failure (IOP>21 mm Hg or glaucoma surgery, or loss of light perception) and (2) surgical complications. A total of 75 patients were included: 37 in the AGV group and 38 in the BGI group. The mean±SD follow-up was 2.3±1.6 years for the AGV group and 2.4±1.7 years for the BGI group (P=0.643). Mean preoperative IOP was 38.7±6.5 mm Hg for the AGV group and 40.8±7.6 mm Hg for the BGI group. At the last follow-up, 10 (27.0%) patients failed in the AGV group compared with 6 (15.8%) patients in the BGI group (P=0.379). The BGI group had higher rate of flat or shallow anterior chamber (n=4, 10%) compared with the AGV group (n=0, 0%) (P=0.043). Failure rates of AGV and BGI in patients with IOP≥30 mm Hg were comparable. There were more early hypotony-related complications in the BGI group; however, none were vision threatening. Both glaucoma drainage implants were effective in treating patients with uncontrolled glaucoma in an emergency setting.

  8. Assessment of conditions affecting surgical success of Ahmed glaucoma valve implants in glaucoma secondary to different uveitis etiologies in adults.

    Science.gov (United States)

    Sungur, G; Yakin, M; Eksioglu, U; Satana, B; Ornek, F

    2017-10-01

    PurposeThere is little known about the long-term efficacy and safety of Ahmed glaucoma valve (AGV) implant and about the conditions affecting surgical success in uveitic glaucoma (UG).Patients and methodsThe charts of adult patients with UG who underwent AGV implantation from 2006 to 2015 were reviewed retrospectively.ResultsData of 46 eyes of 39 patients were evaluated. Mean follow-up was 51.93±23.08 months. Mean preoperative IOP was 37.05±9.62 mm Hg and mean number of preoperative topical anti-glaucomatous medications was 2.98±0.27. One eye (2%) was defined as failure because of implant extraction surgery. In the rest of the eyes, intraocular pressure (IOP) was under control with or without anti-glaucomatous medications during follow-up. The cumulative probability of complete success (IOP control without medications) was 78% at 6 months, 76% at 1 year, 71% at 2 years, 66% at 3 years, and 63% at 4 years (95% confidence interval, 61.24-87.81). The cumulative probability of eyes without complication was 64% at 6 months, 48% at 12 months, 44% at 24 months, 41% at 36 months, and 38% at 48 months (95% confidence interval, 34.64-62.85). Complete success was lower in eyes with previous ocular surgery than the eyes without (P=0.061) and it was lower in eyes with active inflammation at the time of surgery than the eyes without (P=0.011).ConclusionAGV implantation is an effective and safe alternative method in the management of UG, especially when it is performed as a primary surgical option and when no inflammation is present preoperatively.

  9. Bleb Analysis and Short-Term Results of Biodegradable Collagen Matrix-Augmented Ahmed Glaucoma Valve Implantation: 6-Month Follow-up.

    Science.gov (United States)

    Rho, Seungsoo; Sung, Youngje; Ma, Kyoung Tak; Rho, Sae Heun; Kim, Chan Yun

    2015-09-01

    To evaluate the short-term efficacy of a biodegradable collagen matrix (BCM) as an adjuvant for Ahmed valve implantation surgery to prevent the hypertensive phase. This prospective study included 43 refractory glaucoma eyes, all followed for 6 months. Refractory glaucoma was defined as an IOP higher than 20 mm Hg with antiglaucoma eye drops without previous glaucoma surgery. Conventional method was performed in 21 eyes and BCM-augmented Ahmed valve implantation (BAAVI) in 22 eyes. In the BAAVI group, a 10 × 10 × 2-mm BCM was sutured on an Ahmed glaucoma valve FP7 model. Complete success was defined as an IOP of 21 mm Hg or lower (target IOP 1) or 17 mm Hg or lower (target IOP 2) without antiglaucoma medications and qualified success as an IOP of 21 mm Hg or lower with or without medications. Maximal bleb thickness was measured using anterior segment optical coherence tomography images. The preoperative IOPs and numbers of preoperative antiglaucoma medications were similar for both groups. Complete target IOP 1 success rates were 38.1% and 86.4%, complete target IOP 2 success rates were 19.0% and 59.1%, and qualified success rates were 52.4% and 90.9% in the conventional and BAAVI groups, respectively (P < 0.05). The hypertensive phase rate was lower in the BAAVI group (4.5% vs. 47.6%, P = 0.002). Maximal bleb thickness was increased in the BAAVI group on postoperative days 30 and 180 (P < 0.05). Success rates were higher in the BAAVI group than in the conventional group with the change of bleb morphology. Furthermore, use of BCM significantly decreased the need for antiglaucoma medications for at least 6 months postoperatively.

  10. Advanced evacuated tube collectors

    Science.gov (United States)

    Schertz, W. W.; Hull, J. R.; Winston, R.; Ogallagher, J.

    1985-04-01

    The essence of the design concept for these new collectors is the integration of moderate levels of nonimaging concentration inside the evacuated tube itself. This permanently protects the reflection surfaces and allows the use of highly reflecting front surface mirrors with reflectances greater than 95%. Previous fabrication and long term testing of a proof-of-concept prototype has established the technical success of the concept. Present work is directed toward the development of a manufacturable unit that will be suitable for the widest possible range of applications. Design alternatives include scaling up the original prototype's tube diameter from 5 cm to 10 cm, using an internal shaped metal concentrating reflector, using a variety of profile shapes to minimize so-called gap losses and accommodate both single ended and double-ended flow geometries, and allowing the use of heat pipes for the absorber tube.

  11. Square through tube

    International Nuclear Information System (INIS)

    Akita, Junji; Honma, Toei.

    1975-01-01

    Object: To provide a square through tube involving thermal movement in pipelines such as water supply pump driving turbine exhaust pipe (square-shaped), which is wide in freedom with respect to shape and dimension thereof for efficient installation at site. Structure: In a through tube to be airtightly retained for purpose of decontamination in an atomic power plant, comprising a seal rubber plate, a band and a bolt and a nut for securing said plate, the seal rubber plate being worked into the desired shape so that it may be placed in intimate contact with the concrete floor surface by utilization of elasticity of rubber, thereby providing airtightness at a corner portion of the square tube. (Kamimura, M.)

  12. SG tube identification

    International Nuclear Information System (INIS)

    Hoogstraten, P. van

    1994-01-01

    A ''Tracker'' system is described which is designed to identify any tube in a reactor steam generator quickly and safely. Occupational radiation doses to maintenance workers are reduced by using a Tracker and emergency down times are shortened. The system employs a television camera and light source in a stainless steel box with a large window. Both the camera and spotlight can be panned and tilted to reach any point on the tubesheet and are remotely controlled. An operator at a safe working distance can identify any tube visible on a real time video by comparison with the tubesheet pattern stored earlier in the computer memory. The identified tube can then be spotlighted and dealt with quickly by a maintenance worker inside the channel head. (UK)

  13. Test manufacture of the canister insert 135

    International Nuclear Information System (INIS)

    Raiko, H.

    2005-10-01

    This report describes the insert-manufacturing test of a disposal canister for spent nuclear fuel that was made by Metso Foundries Jyvaeskylae Oy, in June 2004 on contract for Posiva Oy. The test manufacture was a part of the co-operation development programme of encapsulation technology between SKB AB and Posiva Oy. Insert casting was specified according to the current manufacturing specifications of SKB. The canister insert was of BWR-type with integral bottom. This was the second trial manufacture of this type of insert in Finland and, in total, the third test manufacture of insert by Metso Foundries Jyvaeskylae Oy. The result fulfilled all the requirements but the material mechanical properties of the cast material. The measured ultimate strength and elongation at rupture were lower than specified in the upper part of the cast. The reason for this was revealed in the metallurgical investigation of the cast material. The cast contained slag (dross). Avoiding the dross formation will be the most demanding challenge of the forthcoming development of the cast procedure. (orig.)

  14. Test manufacture of a canister insert

    International Nuclear Information System (INIS)

    Raiko, H.

    2004-11-01

    This report describes the insert-manufacturing test of a disposal canister for spent nuclear fuel that was made by Metso Paper Oy, Jyvaeskylae Foundry, in 2003 on contract for Posiva Oy. The test manufacture was a part of the co-operation development programme of encapsulation technology between SKB AB and Posiva Oy. Insert casting was specified according to the current manufacturing specifications of SKB. The canister insert was of BWR-type with integral bottom. This was the first trial manufacture of this type of insert in Finland and, in total, the second test manufacture of insert by Metso Paper. The result fulfilled all the requirements but the material mechanical properties and metallurgical structure of the cast material. The measured tensile strength, ultimate strength and elongation at rupture were lower than specified. The reason for this was revealed in the metallurgical investigation of the cast material. The nodulizing of the graphite was not occurred during the casting process according to the requirements. (orig.)

  15. Methods for batch fabrication of cold cathode vacuum switch tubes

    Science.gov (United States)

    Walker, Charles A [Albuquerque, NM; Trowbridge, Frank R [Albuquerque, NM

    2011-05-10

    Methods are disclosed for batch fabrication of vacuum switch tubes that reduce manufacturing costs and improve tube to tube uniformity. The disclosed methods comprise creating a stacked assembly of layers containing a plurality of adjacently spaced switch tube sub-assemblies aligned and registered through common layers. The layers include trigger electrode layer, cathode layer including a metallic support/contact with graphite cathode inserts, trigger probe sub-assembly layer, ceramic (e.g. tube body) insulator layer, and metallic anode sub-assembly layer. Braze alloy layers are incorporated into the stacked assembly of layers, and can include active metal braze alloys or direct braze alloys, to eliminate costs associated with traditional metallization of the ceramic insulator layers. The entire stacked assembly is then heated to braze/join/bond the stack-up into a cohesive body, after which individual switch tubes are singulated by methods such as sawing. The inventive methods provide for simultaneously fabricating a plurality of devices as opposed to traditional methods that rely on skilled craftsman to essentially hand build individual devices.

  16. Sampling of high molecular weight hydrocarbons with adsorbent tubes

    International Nuclear Information System (INIS)

    Stroemberg, B.

    1996-12-01

    Adsorption tubes have been used to determine the content of hydrocarbons in gas samples from small scale combustion and gasification of biomass. Compounds from benzene (mw 78) to indeno (1,2,3-cd) pyrene (mw 276) have been examined. The results show that it is possible to analyze polyaromatic hydrocarbons (PAH) with 4 aromatic rings (mw 202). Detection limits for these compounds are 3 . PAH with higher molecule weight can be identified and quantified in samples with high amounts of PAH e.g. at gasification of biomass. Sampling on adsorption tubes is extremely quick and easy. The tube is inserted in the gas of interest and the sample is sucked through the tube with a pump. Sampling times of 2-10 minutes are often sufficient. High moisture content in the gas may result in losses of the most volatile compounds, when drying. Even very low concentrations of water in the tube may cause ice formation in the cold-trap and the sample will be destroyed. The analysis is unfortunately time-consuming because the desorption oven must be cooled between every analysis. This will reduce the number of samples which can be analyzed per day. The tubes can be stored for several weeks before analysis without deterioration. 4 refs, 5 figs, 3 tabs

  17. PRODUCTION OF URANIUM TUBING

    Science.gov (United States)

    Creutz, E.C.

    1958-04-15

    The manufacture of thin-walled uranium tubing by the hot-piercing techique is described. Uranium billets are preheated to a temperature above 780 d C. The heated billet is fed to a station where it is engaged on its external surface by three convex-surfaced rotating rollers which are set at an angle to the axis of the billet to produce a surface friction force in one direction to force the billet over a piercing mandrel. While being formed around the mandrel and before losing the desired shape, the tube thus formed is cooled by a water spray.

  18. Guide tube sleeve

    International Nuclear Information System (INIS)

    Attix, D.J.

    1983-01-01

    The invention increases the operating capacity of a nuclear reactor by causing a modification in the flow pattern of the coolant which enhances the coolant's effectiveness. The apparatus provides a thin-walled tubular sleeve closely surrounding but not attached to the exterior surface of a guide tube in a fuel assembly. The wall of the sleeve has tabs projecting outwardly into adjacent flow channels. The sleeve is attached to the wall of a cellular void through which passes the guide tube associated with said sleeve. The tabs increase the flow of water in the channel and thus increase the heat transfer

  19. Pressure tube type research reactor

    International Nuclear Information System (INIS)

    Ueda, Hiroshi.

    1976-01-01

    Object: To prevent excessive heat generation due to radiation of a pressure tube vessel. Structure: A pressure tube encasing therein a core comprises a dual construction comprising inner and outer tubes coaxially disposed. High speed cooling water is passed through the inner tube for cooling. In addition, in the outer periphery of said outer tube there is provided a forced cooling tube disposed coaxially thereto, into which cooling fluid, for example, such as moderator or reflector is forcibly passed. This forced cooling tube has its outer periphery surrounded by the vessel into which moderator or reflector is fed. By the provision of the dual construction of the pressure tube and the forced cooling tube, the vessel may be prevented from heat generation. (Ikeda, J.)

  20. Thoracostomy tubes: A comprehensive review of complications and related topics

    Science.gov (United States)

    Kwiatt, Michael; Tarbox, Abigail; Seamon, Mark J.; Swaroop, Mamta; Cipolla, James; Allen, Charles; Hallenbeck, Stacinoel; Davido, H. Tracy; Lindsey, David E.; Doraiswamy, Vijay A.; Galwankar, Sagar; Tulman, David; Latchana, Nicholas; Papadimos, Thomas J.; Cook, Charles H.; Stawicki, Stanislaw P.

    2014-01-01

    Tube thoracostomy (TT) placement belongs among the most commonly performed procedures. Despite many benefits of TT drainage, potential for significant morbidity and mortality exists. Abdominal or thoracic injury, fistula formation and vascular trauma are among the most serious, but more common complications such as recurrent pneumothorax, insertion site infection and nonfunctioning or malpositioned TT also represent a significant source of morbidity and treatment cost. Awareness of potential complications and familiarity with associated preventive, diagnostic and treatment strategies are fundamental to satisfactory patient outcomes. This review focuses on chest tube complications and related topics, with emphasis on prevention and problem-oriented approaches to diagnosis and treatment. The authors hope that this manuscript will serve as a valuable foundation for those who wish to become adept at the management of chest tubes. PMID:25024942

  1. Erythromycin for Promoting the Postpyloric Placement of Feeding Tubes: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Qing-Jun Jiang

    2018-01-01

    Full Text Available Background. Critically ill patients can benefit from enteral nutrition with postpyloric feeding tubes, but the low success rate limits its wide use. Erythromycin could elevate the success rate of tube insertion, but its clinical efficiency still remains controversial. Methods. Included studies must be RCTs which assessed the success rate of postpyloric feeding tube insertion using erythromycin. Results. 284 patients were enrolled in six studies. Meta-analysis showed that erythromycin significantly increases the rate of successful postpyloric feeding tube placement (RR 1.45, 95% CI (1.12, 1.86 and did not increase the risk of adverse effects (RR 2.15, 95% CI (0.20, 22.82. Subgroup analysis showed that unweighted feeding tubes (RR 1.47, 95% CI (1.03, 2.11 could significantly increase the success rate. Country of study, intravenous route of erythromycin, and year of participant enrollment did not influence these results. Conclusions. Erythromycin significantly increases the success rate of postpyloric feeding tube placement. This suggests that erythromycin can be used as an auxiliary method to improve the success rate of bedside insertion.

  2. Double wall steam generator tubing

    International Nuclear Information System (INIS)

    Padden, T.R.; Uber, C.F.

    1983-01-01

    Double-walled steam generator tubing for the steam generators of a liquid metal cooled fast breeder reactor prevents sliding between the surfaces due to a mechanical interlock. Forces resulting from differential thermal expansion between the outer tube and the inner tube are insufficient in magnitude to cause shearing of base metal. The interlock is formed by jointly drawing the tubing, with the inside wall of the outer tube being already formed with grooves. The drawing causes the outer wall of the inner tube to form corrugations locking with the grooves. (author)

  3. RERTR-12 Insertion 1 Irradiation Summary Report

    International Nuclear Information System (INIS)

    Perez, D.M.; Lillo, M.A.; Chang, G.S.; Woolstenhulme, N.E.; Roth, G.A.; Wachs, D.M.

    2012-01-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications. RERTR-12 insertion 1 includes the capsules irradiated during the first two irradiation cycles. These capsules include Z, X1, X2 and X3 capsules. The following report summarizes the life of the RERTR-12 insertion 1 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  4. RERTR-12 Insertion 2 Irradiation Summary Report

    International Nuclear Information System (INIS)

    Perez, D.M.; Chang, G.S.; Wachs, D.M.; Roth, G.A.; Woolstenhulme, N.E.

    2012-01-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  5. Installation of the LHC experimental insertions

    CERN Document Server

    Bartolome-Jimenez, S

    2004-01-01

    The installation of the LHC experimental insertions, and particularly the installation of the low-beta quadrupoles, raises many technical challenges due to the stringent alignment specifications and to the difficulty of access in very confined areas. The compact layout with many lattice elements, vacuum components, beam control instrumentation and the presence of shielding does not allow for any improvisation in the installation procedure. This paper reviews all the constraints that need to be taken into account when installing the experimental insertions. It describes the chronological sequence of installation and discusses the technical solutions that have been adopted.

  6. INSTALLATION OF THE LHC EXPERIMENTAL INSERTIONS

    CERN Document Server

    Bartolome-Jimenez, S

    2004-01-01

    The installation of the LHC experimental insertions, and particularly the installation of the Low-Beta quadrupoles, raises many technical challenges due to the stringent alignment specifications and to the difficulty of access in very confined areas. The compact layout with many lattice elements, vacuum components, beam control instrumentation and the presence of shielding does not allow for any improvisation in the installation procedure. This paper reviews all the constraints that need to be taken into account when installing the experimental insertions. It describes the chronological sequence of installation and discusses the technical solutions that have been adopted.

  7. Compact insert design for cryogenic pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, Salvador M.; Ledesma-Orozco, Elias Rigoberto; Espinosa-Loza, Francisco; Petitpas, Guillaume; Switzer, Vernon A.

    2017-06-14

    A pressure vessel apparatus for cryogenic capable storage of hydrogen or other cryogenic gases at high pressure includes an insert with a parallel inlet duct, a perpendicular inlet duct connected to the parallel inlet. The perpendicular inlet duct and the parallel inlet duct connect the interior cavity with the external components. The insert also includes a parallel outlet duct and a perpendicular outlet duct connected to the parallel outlet duct. The perpendicular outlet duct and the parallel outlet duct connect the interior cavity with the external components.

  8. ALS insertion device block measurement and inspection

    International Nuclear Information System (INIS)

    Marks, S.; Carrieri, J.; Cook, C.; Hassenzahl, W.V.; Hoyer, E.; Plate, D.

    1991-05-01

    The performance specifications for ALS insertion devices require detailed knowledge and strict control of the Nd-Fe-B permanent magnet blocks incorporated in these devices. This paper describes the measurement and inspection apparatus and the procedures designed to qualify and characterize these blocks. A detailed description of a new, automated Helmholtz coil facility for measurement of the three components of magnetic moment is included. Physical block inspection and magnetic moment measurement procedures are described. Together they provide a basis for qualifying blocks and for specifying placement of blocks within an insertion devices' magnetic structures. 1 ref., 4 figs

  9. A longitudinal evaluation of hearing and ventilation tube insertion in patients with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Andersen, Tobias Nicolai; Alanin, Mikkel Christian; von Buchwald, Christian

    2016-01-01

    INTRODUCTION: Primary ciliary dyskinesia (PCD) is an autosomal recessive genetic disease, which primarily manifests with oto-sino-pulmonary symptoms. Otitis media with effusion (OME) is common from early childhood. The existing literature on OME management in PCD is conflicting. The goals of the ...

  10. Tube-dwelling invertebrates

    NARCIS (Netherlands)

    Hölker, Franz; Vanni, Michael J.; Kuiper, Jan J.; Meile, Christof; Grossart, Hans Peter; Stief, Peter; Adrian, Rita; Lorke, Andreas; Dellwig, Olaf; Brand, Andreas; Hupfer, Michael; Mooij, Wolf M.; Nützmann, Gunnar; Lewandowski, Jörg

    2015-01-01

    There is ample evidence that tube-dwelling invertebrates such as chironomids significantly alter multiple important ecosystem functions, particularly in shallow lakes. Chironomids pump large water volumes, and associated suspended and dissolved substances, through the sediment and thereby compete

  11. Cladding tube manufacturing technology

    International Nuclear Information System (INIS)

    Hahn, R.; Jeong, Y. H.; Baek, B. J.; Kim, K. H.; Kim, S. J.; Choi, B. K.; Kim, J. M.

    1999-04-01

    This report gives an overview of the manufacturing routine of PWR cladding tubes. The routine essentially consists of a series of deformation and annealing processes which are necessary to transform the ingot geometry to tube dimensions. By changing shape, microstructure and structure-related properties are altered simultaneously. First, a short overview of the basics of that part of deformation geometry is given which is related to tube reducing operations. Then those processes of the manufacturing routine which change the microstructure are depicted, and the influence of certain process parameters on microstructure and material properties are shown. The influence of the resulting microstructure on material properties is not discussed in detail, since it is described in my previous report A lloy Development for High Burnup Cladding . Because of their paramount importance still up to now, and because manufacturing data and their influence on properties for other alloys are not so well established or published, the descriptions are mostly related to Zry4 tube manufacturing, and are only in short for other alloys. (author). 9 refs., 46 figs

  12. Thoughts on accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1978-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  13. Tracheostomy tube - speaking

    Science.gov (United States)

    ... with others. However, you can learn how to speak with a tracheostomy tube. It just takes practice. There ... If it is hard to speak with a trach in place, special devices can help you learn to create sounds. One-way valves, called speaking valves, are placed ...

  14. Thoughts of accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  15. Cladding tube manufacturing technology

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R. [Kraftwerk Union AG, Mulheim (Germany); Jeong, Y.H.; Baek, B.J.; Kim, K.H.; Kim, S.J.; Choi, B.K.; Kim, J.M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-04-01

    This report gives an overview of the manufacturing routine of PWR cladding tubes. The routine essentially consists of a series of deformation and annealing processes which are necessary to transform the ingot geometry to tube dimensions. By changing shape, microstructure and structure-related properties are altered simultaneously. First, a short overview of the basics of that part of deformation geometry is given which is related to tube reducing operations. Then those processes of the manufacturing routine which change the microstructure are depicted, and the influence of certain process parameters on microstructure and material properties are shown. The influence of the resulting microstructure on material properties is not discussed in detail, since it is described in my previous report 'Alloy Development for High Burnup Cladding.' Because of their paramount importance still up to now, and because manufacturing data and their influence on properties for other alloys are not so well established or published, the descriptions are mostly related to Zry4 tube manufacturing, and are only in short for other alloys. (author). 9 refs., 46 figs.

  16. Neutron absorber inserts for 55-gal drums

    International Nuclear Information System (INIS)

    Wilson, R.E.; Kim, Y.S.; Toffer, H.

    2000-01-01

    Transport and temporary storage of more than 200 g of fissile material in 55-gal drums at the Rocky Flats Environmental Technology Site (RFETS) have received significant attention during the cleanup mission. This paper discusses successful applications and results of extensive computer studies. Interim storage and movement of fissile material in excess of standard drum limits (200 g) in a safe configuration have been accomplished using special drum inserts. Such inserts have constrained the contents of a drum to two 4-ell bottles. The content of the bottles was limited to 600 g Pu or U in solution or a total of 1200 g for the entire drum. The inserts were a simple design constructed of stainless steel, forming a vertical cylindrical pipe into which two bottles, one on top of the other, could be centered in the drum. The remaining drum volume was configured to preclude any additional bottle placement external to the vertical cylinder. Such inserts in drums were successfully used in moving high-concentration solution from one building to another for chemical processing. Concern about the knowledge of fissile material concentration in bottles prompted another study for drum inserts. The past practice had been to load up to fourteen 4-ell bottles into 55-gal drums, provided the fissile material concentration was < 6 g fissile/ell, and the total drum contents of 200 g fissile was not exceeded. Only one determination of the solution concentration was needed. An extensive safety analysis concluded that a single measurement of bottle content could not ensure compliance with double-contingency-criterion requirements. A second determination of the bottle contents was required before bottles could be placed in a 55-gal drum. Al alternative to a dual-measurement protocol, which is for bolstering administrative control, was to develop an engineered safety feature that would eliminate expensive tests and administrative decisions. A drum insert design was evaluated that would

  17. Face and content validity of a virtual-reality simulator for myringotomy with tube placement.

    Science.gov (United States)

    Huang, Caiwen; Cheng, Horace; Bureau, Yves; Agrawal, Sumit K; Ladak, Hanif M

    2015-10-20

    Myringotomy with tube insertion can be challenging for junior Otolaryngology residents as it is one of the first microscopic procedures they encounter. The Western myringotomy simulator was developed to allow trainees to practice microscope positioning, myringotomy, and tube placement. This virtual-reality simulator is viewed in stereoscopic 3D, and a haptic device is used to manipulate the digital ear model and surgical tools. To assess the face and content validity of the Western myringotomy simulator. The myringotomy simulator was integrated with new modules to allow speculum placement, manipulation of an operative microscope, and insertion of the ventilation tube through a deformable tympanic membrane. A questionnaire was developed in consultation with instructing surgeons. Fourteen face validity questions focused on the anatomy of the ear, simulation of the operative microscope, appearance and movement of the surgical instruments, deformation and cutting of the eardrum, and myringotomy tube insertion. Six content validity questions focused on training potential on surgical tasks such as speculum placement, microscope positioning, tool navigation, ear anatomy, myringotomy creation and tube insertion. A total of 12 participants from the Department of Otolaryngology-Head and Neck Surgery were recruited for the study. Prior to completing the questionnaire, participants were oriented to the simulator and given unlimited time to practice until they were comfortable with all of its aspects. Responses to 12 of the 14 questions on face validity were predominantly positive. One issue of concern was with contact modeling related to tube insertion into the eardrum, and the second was with the movement of the blade and forceps. The former could be resolved by using a higher resolution digital model for the eardrum to improve contact localization. The latter could be resolved by using a higher fidelity haptic device. With regard to content validity, 64% of the responses

  18. Radioactivity transport following steam generator tube rupture

    International Nuclear Information System (INIS)

    Hopenfeld, J.

    1985-03-01

    A review of the capabilities of the CITADEL computer code as well as plant experience to project radioactivity releases following a steam generator tube rupture in PWR's shows that certain experimental data are needed for reliable off-site dose predictions. This article defines five parameters which are the key for such predictions and discusses the functional dependence of these parameters on various operational variables. The above parameters can be used in conjunction with CITADEL or they can be inserted in the appropriate equations which then conveniently can be programmed as a subroutine in thermal-hydraulic system codes. A joint Westinghouse, Electric Power Research Institute and Nuclear Regulatory Commission Program aimed at obtaining the five parameters empirically is described

  19. An in vitro comparison of tracheostomy tube cuffs

    Directory of Open Access Journals (Sweden)

    Maguire S

    2015-04-01

    Full Text Available Seamus Maguire,1 Frances Haury,2 Korinne Jew2 1Research and Development, Covidien Respiratory and Monitoring Solutions, Athlone, Ireland; 2Medical Affairs, Covidien Respiratory and Monitoring Solutions, Boulder, CO, USA Introduction: The Shiley™ Flexible adult tracheostomy tube with TaperGuard™ cuff has been designed through its geometry, materials, diameter, and wall thickness to minimize micro-aspiration of fluids past the cuff and to provide an effective air seal in the trachea while also minimizing the risk of excessive contact pressure on the tracheal mucosa. The cuff also has a deflated profile that may allow for easier insertion through the stoma site. This unique design is known as the TaperGuard™ cuff. The purpose of the observational, in vitro study reported here was to compare the TaperGuard™ taper-shaped cuff to a conventional high-volume low-pressure cylindrical-shaped cuff (Shiley™ Disposable Inner Cannula Tracheostomy Tube [DCT] with respect to applied tracheal wall pressure, air and fluid sealing efficacy, and insertion force.Methods: Three sizes of tracheostomy tubes with the two cuff types were placed in appropriately sized tracheal models and lateral wall pressure was measured via pressure-sensing elements on the inner surface. Fluid sealing performance was assessed by inflating the cuffs within the tracheal models (25 cmH2O, instilling water above the cuff, and measuring fluid leakage past the cuff. To measure air leak, tubes were attached to a test lung and ventilator, and leak was calculated by subtracting the average exhaled tidal volume from the average delivered tidal volume. A tensile test machine was used to measure insertion force for each tube with the cuff deflated to simulate clinical insertion through a stoma site.Results: The average pressure exerted on the lateral wall of the model trachea was lower for the taper-shaped cuff than for the cylindrical cuff under all test conditions (P<0.05. The taper

  20. Direct random insertion mutagenesis of Helicobacter pylori.

    NARCIS (Netherlands)

    Jonge, de R.; Bakker, D.; Vliet, van AH; Kuipers, E.J.; Vandenbroucke-Grauls, C.M.J.E.; Kusters, J.G.

    2003-01-01

    Random insertion mutagenesis is a widely used technique for the identification of bacterial virulence genes. Most strategies for random mutagenesis involve cloning in Escherichia coli for passage of plasmids or for phenotypic selection. This can result in biased selection due to restriction or