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Sample records for optimized surgical techniques

  1. Techniques for Optimizing Surgical Scars, Part 2: Hypertrophic Scars and Keloids.

    Science.gov (United States)

    Potter, Kathryn; Konda, Sailesh; Ren, Vicky Zhen; Wang, Apphia Lihan; Srinivasan, Aditya; Chilukuri, Suneel

    2017-01-01

    Surgical management of benign or malignant cutaneous tumors may result in noticeable scars that are of great concern to patients, regardless of sex, age, or ethnicity. Techniques to optimize surgical scars are discussed in this three-part review. Part 2 focuses on scar revision for hypertrophic and keloids scars. Scar revision options for hypertrophic and keloid scars include corticosteroids, bleomycin, fluorouracil, verapamil, avotermin, hydrogel scaffold, nonablative fractional lasers, ablative and fractional ablative lasers, pulsed dye laser (PDL), flurandrenolide tape, imiquimod, onion extract, silicone, and scar massage.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  3. Optimized positioning of autonomous surgical lamps

    Science.gov (United States)

    Teuber, Jörn; Weller, Rene; Kikinis, Ron; Oldhafer, Karl-Jürgen; Lipp, Michael J.; Zachmann, Gabriel

    2017-03-01

    We consider the problem of finding automatically optimal positions of surgical lamps throughout the whole surgical procedure, where we assume that future lamps could be robotized. We propose a two-tiered optimization technique for the real-time autonomous positioning of those robotized surgical lamps. Typically, finding optimal positions for surgical lamps is a multi-dimensional problem with several, in part conflicting, objectives, such as optimal lighting conditions at every point in time while minimizing the movement of the lamps in order to avoid distractions of the surgeon. Consequently, we use multi-objective optimization (MOO) to find optimal positions in real-time during the entire surgery. Due to the conflicting objectives, there is usually not a single optimal solution for such kinds of problems, but a set of solutions that realizes a Pareto-front. When our algorithm selects a solution from this set it additionally has to consider the individual preferences of the surgeon. This is a highly non-trivial task because the relationship between the solution and the parameters is not obvious. We have developed a novel meta-optimization that considers exactly this challenge. It delivers an easy to understand set of presets for the parameters and allows a balance between the lamp movement and lamp obstruction. This metaoptimization can be pre-computed for different kinds of operations and it then used by our online optimization for the selection of the appropriate Pareto solution. Both optimization approaches use data obtained by a depth camera that captures the surgical site but also the environment around the operating table. We have evaluated our algorithms with data recorded during a real open abdominal surgery. It is available for use for scientific purposes. The results show that our meta-optimization produces viable parameter sets for different parts of an intervention even when trained on a small portion of it.

  4. Fronto-orbital feminization technique. A surgical strategy using fronto-orbital burring with or without eggshell technique to optimize the risk/benefit ratio.

    Science.gov (United States)

    Villepelet, A; Jafari, A; Baujat, B

    2018-05-04

    The demand for facial feminization is increasing in transsexual patients. Masculine foreheads present extensive supraorbital bossing with a more acute glabellar angle, whereas female foreheads show softer features. The aim of this article is to describe our surgical technique for fronto-orbital feminization. The mask-lift technique is an upper face-lift. It provides rejuvenation by correcting collapsed features, and fronto-orbital feminization through burring of orbital rims and lateral canthopexies. Depending on the size of the frontal sinus and the thickness of its anterior wall, frontal remodeling is achieved using simple burring or by means of the eggshell technique. Orbital remodeling comprises a superolateral orbital opening, a reduction of ridges and a trough at the lateral orbital rim to support the lateral canthopexy. Frontal, corrugator and procerus myectomies, plus minimal scalp excision, complete the surgery. Our technique results in significant, natural-looking feminization. No complications were observed in our series of patients. The eggshell technique is an alternative to bone flap on over-pneumatized sinus. Fronto-orbital feminization fits into a wider surgical strategy. It can be associated to rhinoplasty, genioplasty, mandibular angle remodeling, face lift and laryngoplasty. Achieving facial feminization in 2 or 3 stages improves psychological and physiological tolerance. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  5. Journal of Surgical Technique and Case Report

    African Journals Online (AJOL)

    The aim of Journal of Surgical Technique and Case Report is to advance surgical knowledge and practice by promoting the reporting of innovative and reproducible surgical techniques ... Anterior palatal island advancement flap for bone graft coverage: technical note · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  6. Changes in urological surgical techniques

    Directory of Open Access Journals (Sweden)

    Oktay Üçer

    2010-06-01

    Full Text Available Recently, laparoscopic and afterwards robotic techniques have constituted most of urologic surgery procedures. Open surgery may give place to robotic surgery due to possible widespread use of robots in the future. Studies, that compare these two techniques are usually designed about radical prostatectomy, since it is the most common operation performed by using these techniques. In literature,robotic surgery seems more advantageous than other techniques but the most important disadvantage of this technique is cost-effective problems. In present review,history of open, laparoscopic and robotic surgery, and comparison of advantages, disadvantages and cost of these techniques have been discussed with literature.

  7. Problems associated with basic oral surgical techniques

    International Nuclear Information System (INIS)

    Kapatkin, A.S.; Marretta, S.M.; Schloss, A.J.

    1990-01-01

    The veterinarian must be able to diagnose several types of dental problems. History, physical examination, clinical pathology, and radiography are important in making an accurate diagnosis. Basic oral surgery includes various extraction techniques and management of their associated complications. Knowledge of dental anatomy and proper surgical technique can make an extraction curative rather than a frustrating procedure with multiple complications

  8. Journal of Surgical Technique and Case Report: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. The aim of Journal of Surgical Technique and Case Report is to advance surgical knowledge and practice by promoting the reporting of innovative and reproducible surgical techniques and illustrative surgical cases on various surgical disciplines. The journal encourages authoritative synthesis of current ...

  9. Surgical implantation techniques for electronic tags in fish

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Glenn N.; Cooke, Steven J.; Brown, Richard S.; Deters, Katherine A.

    2011-01-01

    Intracoelomic implantation of transmitters into fish requires making a surgical incision, incision closure, and other surgery related techniques; however, the tools and techniques used in the surgical process vary widely. We review the available literature and focus on tools and techniques used for conducting surgery on juvenile salmonids because of the large amount of research that is conducted on them. The use of sterilized surgical instruments properly selected for a given size of fish will minimize tissue damage and infection rates, and speed the wound healing of fish implanted with transmitters. For the implantation of transmitters into small fish, the optimal surgical methods include making an incision on the ventral midline along the linea alba (for studies under 1 month), protecting the viscera (by lifting the skin with forceps while creating the incision), and using absorbable monofilament suture with a small-swaged-on swaged-on tapered or reverse-cutting needle. Standardizing the implantation techniques to be used in a study involving particular species and age classes of fish will improve survival and transmitter retention while allowing for comparisons to be made among studies and across multiple years. This review should be useful for researchers working on juvenile salmonids and other sizes and species of fish.

  10. Mechanical Design Optimization Using Advanced Optimization Techniques

    CERN Document Server

    Rao, R Venkata

    2012-01-01

    Mechanical design includes an optimization process in which designers always consider objectives such as strength, deflection, weight, wear, corrosion, etc. depending on the requirements. However, design optimization for a complete mechanical assembly leads to a complicated objective function with a large number of design variables. It is a good practice to apply optimization techniques for individual components or intermediate assemblies than a complete assembly. Analytical or numerical methods for calculating the extreme values of a function may perform well in many practical cases, but may fail in more complex design situations. In real design problems, the number of design parameters can be very large and their influence on the value to be optimized (the goal function) can be very complicated, having nonlinear character. In these complex cases, advanced optimization algorithms offer solutions to the problems, because they find a solution near to the global optimum within reasonable time and computational ...

  11. Acute bacterial endocarditis. Optimizing surgical results.

    Science.gov (United States)

    Larbalestier, R I; Kinchla, N M; Aranki, S F; Couper, G S; Collins, J J; Cohn, L H

    1992-11-01

    Acute bacterial endocarditis continues to be a condition with high morbidity. Although the majority of patients are treated by high-dose antibiotics, a high-risk patient group requires surgical intervention, which is the subject of this article. From 1972 to 1991, 3,820 patients underwent heart valve replacement at the Brigham and Women's Hospital, Boston. Of this group, 158 patients underwent surgery for acute bacterial endocarditis: 109 had native valve endocarditis (NVE), and 49 had prosthetic valve endocarditis (PVE). There were 108 men and 50 women with a mean age of 49 years (range, 16-79 years); 64% were New York Heart Association functional class IV before surgery, and 12% of the group had a history of intravenous drug abuse. In both NVE and PVE groups, Streptococcus was the predominant infecting agent. Uncontrolled sepsis, progressive congestive failure, peripheral emboli, and echocardiographically demonstrated vegetations were the most common indications for surgery. Eighty-five percent of patients had a single-valve procedure, 15% had a multivalve procedure, and 34 patients had other associated major cardiac procedures. The operative mortality was 6% in NVE and 22% in PVE. Long-term survival at 10 years was 66% for NVE and 29% for PVE. Freedom from recurrent endocarditis at 10 years was 85% for NVE and 82% for PVE. The main factors associated with decreased survival overall were PVE and nonstreptococcal infection. The morbidity and mortality after surgical treatment of acute endocarditis depend on the site, the severity, and the subject infected. Early aggressive surgical intervention is indicated to optimize surgical results, especially in patients with nonstreptococcal infection or PVE.

  12. Coblation versus other surgical techniques for tonsillectomy.

    Science.gov (United States)

    Pynnonen, Melissa; Brinkmeier, Jennifer V; Thorne, Marc C; Chong, Lee Yee; Burton, Martin J

    2017-08-22

    Tonsillectomy is a very common operation and is performed using various surgical methods. Coblation is a popular method because it purportedly causes less pain than other surgical methods. However, the superiority of coblation is unproven. To compare the effects of coblation tonsillectomy for chronic tonsillitis or tonsillar hypertrophy with other surgical techniques, both hot and cold, on intraoperative morbidity, postoperative morbidity and procedural cost. The Cochrane ENT Information Specialist searched the ENT Trials Register; Central Register of Controlled Trials (CENTRAL 2017, Issue 3); PubMed; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 20 April 2017. Randomised controlled trials (RCTs) of children and adults undergoing tonsillectomy with coblation compared with any other surgical technique. This review is limited to trials of extracapsular (traditional) tonsillectomy and excludes trials of intracapsular tonsil removal (tonsillotomy). We used the standard Cochrane methods. Our primary outcomes were: patient-reported pain using a validated pain scale at postoperative days 1, 3 and 7; intraoperative blood loss; primary postoperative bleeding (within 24 hours) and secondary postoperative bleeding (more than 24 hours after surgery). Secondary outcomes were: time until resumption of normal diet, time until resumption of normal activity, duration of surgery and adverse effects including blood transfusion and the need for reoperation. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics. We included 29 studies, with a total of 2561 participants. All studies had moderate or high risk of bias. Sixteen studies used an adequate randomisation technique, however the inability to mask the surgical teams and/or provide adequate methods to mitigate the risk of bias put nearly all studies at moderate or high risk of

  13. Numerical optimization of alignment reproducibility for customizable surgical guides.

    Science.gov (United States)

    Kroes, Thomas; Valstar, Edward; Eisemann, Elmar

    2015-10-01

    Computer-assisted orthopedic surgery aims at minimizing invasiveness, postoperative pain, and morbidity with computer-assisted preoperative planning and intra-operative guidance techniques, of which camera-based navigation and patient-specific templates (PST) are the most common. PSTs are one-time templates that guide the surgeon initially in cutting slits or drilling holes. This method can be extended to reusable and customizable surgical guides (CSG), which can be adapted to the patients' bone. Determining the right set of CSG input parameters by hand is a challenging task, given the vast amount of input parameter combinations and the complex physical interaction between the PST/CSG and the bone. This paper introduces a novel algorithm to solve the problem of choosing the right set of input parameters. Our approach predicts how well a CSG instance is able to reproduce the planned alignment based on a physical simulation and uses a genetic optimization algorithm to determine optimal configurations. We validate our technique with a prototype of a pin-based CSG and nine rapid prototyped distal femora. The proposed optimization technique has been compared to manual optimization by experts, as well as participants with domain experience. Using the optimization technique, the alignment errors remained within practical boundaries of 1.2 mm translation and [Formula: see text] rotation error. In all cases, the proposed method outperformed manual optimization. Manually optimizing CSG parameters turns out to be a counterintuitive task. Even after training, subjects with and without anatomical background fail in choosing appropriate CSG configurations. Our optimization algorithm ensures that the CSG is configured correctly, and we could demonstrate that the intended alignment of the CSG is accurately reproduced on all tested bone geometries.

  14. Finger replantation: surgical technique and indications.

    Science.gov (United States)

    Barbary, S; Dap, F; Dautel, G

    2013-12-01

    In this article, we discuss the surgical technique of finger replantation in detail, distinguishing particularities of technique in cases of thumb amputation, children fingertip replantation, ring finger avulsion, and very distal replantations. We emphasize the principles of bone shortening, the spare part concept, the special importance of nerve sutures and the use of vein graft in case of avulsion or crushing. However, even if finger replantation is now a routine procedure, a clear distinction should be made between revascularization and functional success. The indications for finger replantation are then detailed in the second part of this paper. The absolute indications for replantation are thumb, multiple fingers, transmetacarpal or hand, and any upper extremity amputation in a child whatever the level. Fingertip amputations distal to the insertion of the Flexor digitorum superficialis (FDS) are also a good indication. Other cases are more controversial because of the poor functional outcome, especially for the index finger, which is often functionally excluded. Copyright © 2013. Published by Elsevier SAS.

  15. Surgical Tips in Frozen Abdomen Management: Application of Coliseum Technique.

    Science.gov (United States)

    Kyriazanos, Ioannis D; Manatakis, Dimitrios K; Stamos, Nikolaos; Stoidis, Christos

    2015-01-01

    Wound dehiscence is a serious postoperative complication, with an incidence of 0.5-3% after primary closure of a laparotomy incision, and represents an acute mechanical failure of wound healing. Relatively recently the concept of "intentional open abdomen" was described and both clinical entities share common pathophysiological and clinical pathways ("postoperative open abdominal wall"). Although early reconstruction is the target, a significant proportion of patients will develop adhesions between abdominal viscera and the anterolateral abdominal wall, a condition widely recognized as "frozen abdomen," where delayed wound closure appears as the only realistic alternative. We report our experience with a patient who presented with frozen abdomen after wound dehiscence due to surgical site infection and application of the "Coliseum technique" for its definitive surgical management. This novel technique represents an innovative alternative to abdominal exploration, for cases of "malignant" frozen abdomen due to peritoneal carcinomatosis. Lifting the edges of the surgical wound upwards and suspending them under traction by threads from a retractor positioned above the abdomen facilitates approach to the peritoneal cavity, optimizes exposure of intra-abdominal organs, and prevents operative injury to the innervation and blood supply of abdominal wall musculature, a crucial step for subsequent hernia repair.

  16. Evolving Educational Techniques in Surgical Training.

    Science.gov (United States)

    Evans, Charity H; Schenarts, Kimberly D

    2016-02-01

    Training competent and professional surgeons efficiently and effectively requires innovation and modernization of educational methods. Today's medical learner is quite adept at using multiple platforms to gain information, providing surgical educators with numerous innovative avenues to promote learning. With the growth of technology, and the restriction of work hours in surgical education, there has been an increase in use of simulation, including virtual reality, robotics, telemedicine, and gaming. The use of simulation has shifted the learning of basic surgical skills to the laboratory, reserving limited time in the operating room for the acquisition of complex surgical skills". Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Surgical techniques for lumbo-sacral fusion.

    Science.gov (United States)

    Tropiano, P; Giorgi, H; Faure, A; Blondel, B

    2017-02-01

    Lumbo-sacral (L5-S1) fusion is a widely performed procedure that has become the reference standard treatment for refractory low back pain. L5-S1 is a complex transition zone between the mobile lordotic distal lumbar spine and the fixed sacral region. The goal is to immobilise the lumbo-sacral junction in order to relieve pain originating from this site. Apart from achieving inter-vertebral fusion, the main challenge lies in the preoperative determination of the fixed L5-S1 position that will be optimal for the patient. Many lumbo-sacral fusion techniques are available. Stabilisation can be achieved using various methods. An anterior, posterior, or combined approach may be used. Recently developed minimally invasive techniques are gaining in popularity based on their good clinical outcomes and high fusion rates. The objective of this conference is to resolve the main issues faced by spinal surgeons in their everyday practice. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Selection of oncoplastic surgical technique in Asian breast cancer patients

    Directory of Open Access Journals (Sweden)

    Eui Sun Shin

    2018-01-01

    Full Text Available Background Oncoplastic surgery is being increasingly performed in Korean women; however, unlike Westerners, Korean women usually have small to moderate-sized breasts. To achieve better outcomes in reconstructed breasts, several factors should be considered to determine the optimal surgical method. Methods A total of 108 patients who underwent oncoplastic surgery from January 2013 to December 2016 were retrospectively investigated. We used various methods, including glandular tissue reshaping, latissimus dorsi (LD flap transposition, and reduction oncoplasty, to restore the breast volume and symmetry. Results The mean weight of the tumor specimens was 40.46 g, and the ratio of the tumor specimen weight to breast volume was 0.12 g/mL in the patients who underwent glandular tissue reshaping (n=59. The corresponding values were 101.47 g and 0.14 g/mL, respectively, in the patients who underwent reduction oncoplasty (n=17, and 82.54 g and 0.20 g/mL, respectively, in those treated with an LD flap (n=32. Glandular tissue reshaping was mostly performed in the upper outer quadrant, and LD flap transposition was mostly performed in the lower inner quadrant. No major complications were noted. Most patients were satisfied with the aesthetic results. Conclusions We report satisfactory outcomes of oncoplastic surgical procedures in Korean patients. The results regarding specimen weight and the tumor-to-breast ratio of Asian patients will be a helpful reference point for determining the most appropriate oncoplastic surgical technique.

  19. Computer-Assisted Technique for Surgical Tooth Extraction

    Directory of Open Access Journals (Sweden)

    Hosamuddin Hamza

    2016-01-01

    Full Text Available Introduction. Surgical tooth extraction is a common procedure in dentistry. However, numerous extraction cases show a high level of difficulty in practice. This difficulty is usually related to inadequate visualization, improper instrumentation, or other factors related to the targeted tooth (e.g., ankyloses or presence of bony undercut. Methods. In this work, the author presents a new technique for surgical tooth extraction based on 3D imaging, computer planning, and a new concept of computer-assisted manufacturing. Results. The outcome of this work is a surgical guide made by 3D printing of plastics and CNC of metals (hybrid outcome. In addition, the conventional surgical cutting tools (surgical burs are modified with a number of stoppers adjusted to avoid any excessive drilling that could harm bone or other vital structures. Conclusion. The present outcome could provide a minimally invasive technique to overcome the routine complications facing dental surgeons in surgical extraction procedures.

  20. New techniques in dental surgical CT

    International Nuclear Information System (INIS)

    Rabin, D.N.; Rabin, H.; Sakowicz, B.A.; Rabin, M.A.; Rabin, S.I.; Schwartz, A.

    1991-01-01

    This paper demonstrates how CT can be used with dental software to evaluate prosthetic failure and for planning dental implants when a stent is used. The Food and Drug Administration issued a safety alert for proplast-coated temporomandibular joint prostheses. Prosthetic failure occurs with migration, fragmentation, or bone erosion. Sagittal CT requiring a special head holder can instead be performed with reformatted sagittal images. The technique of dental implant CT changes when a dental stent is used to provide more accurate implant anchorage and planning. Images must be parallel to the occlusal plane. We will demonstrate these techniques and present their rationale

  1. Soft Tissue Surgical Procedures for Optimizing Anterior Implant Esthetics

    Science.gov (United States)

    Ioannou, Andreas L.; Kotsakis, Georgios A.; McHale, Michelle G.; Lareau, Donald E.; Hinrichs, James E.; Romanos, Georgios E.

    2015-01-01

    Implant dentistry has been established as a predictable treatment with excellent clinical success to replace missing or nonrestorable teeth. A successful esthetic implant reconstruction is predicated on two fundamental components: the reproduction of the natural tooth characteristics on the implant crown and the establishment of soft tissue housing that will simulate a healthy periodontium. In order for an implant to optimally rehabilitate esthetics, the peri-implant soft tissues must be preserved and/or augmented by means of periodontal surgical procedures. Clinicians who practice implant dentistry should strive to achieve an esthetically successful outcome beyond just osseointegration. Knowledge of a variety of available techniques and proper treatment planning enables the clinician to meet the ever-increasing esthetic demands as requested by patients. The purpose of this paper is to enhance the implant surgeon's rationale and techniques beyond that of simply placing a functional restoration in an edentulous site to a level whereby an implant-supported restoration is placed in reconstructed soft tissue, so the site is indiscernible from a natural tooth. PMID:26124837

  2. The surgical correction of buried penis: a new technique

    NARCIS (Netherlands)

    Boemers, T. M.; de Jong, T. P.

    1995-01-01

    We report a new surgical technique for the correction of buried penis. The study comprised 10 boys with buried penis. The technique consisted of resection of abnormal dartos attachments, unfurling of the prepuce and correction of the deficient shaft skin by reapproximation of the preputial skin

  3. Evolution of surgical techniques for a progressive risk reduction.

    Science.gov (United States)

    Amato, Bruno; Santoro, Mario; Izzo, Raffaele; Servillo, Giuseppe; Compagna, Rita; Di Domenico, Lorenza; Di Nardo, Veronica; Giugliano, Giuseppe

    2017-07-18

    Advanced age is a strong predictor of high perioperative mortality in surgical patients and patients aged 75 years and older have an elevated surgical risk, much higher than that of younger patients. Progressive advances in surgical techniques now make it possible to treat high-risk surgical patients with minimally invasive procedures. Endovascular techniques have revolutionized the treatment of several vascular diseases, in particular carotid stenosis, aortic pathologies, and severely incapacitating intermittent claudication or critical limb ischemia. The main advantages of the endovascular approach are the low complication rate, high rate of technical success and a good clinical outcome. Biliary stenting has improved the clinical status of severely ill patients with bile duct stricture before major surgery, and represents a good palliative therapy in the case of malignant biliary obstruction.

  4. Simulation-based optimization parametric optimization techniques and reinforcement learning

    CERN Document Server

    Gosavi, Abhijit

    2003-01-01

    Simulation-Based Optimization: Parametric Optimization Techniques and Reinforcement Learning introduces the evolving area of simulation-based optimization. The book's objective is two-fold: (1) It examines the mathematical governing principles of simulation-based optimization, thereby providing the reader with the ability to model relevant real-life problems using these techniques. (2) It outlines the computational technology underlying these methods. Taken together these two aspects demonstrate that the mathematical and computational methods discussed in this book do work. Broadly speaking, the book has two parts: (1) parametric (static) optimization and (2) control (dynamic) optimization. Some of the book's special features are: *An accessible introduction to reinforcement learning and parametric-optimization techniques. *A step-by-step description of several algorithms of simulation-based optimization. *A clear and simple introduction to the methodology of neural networks. *A gentle introduction to converg...

  5. Physical optimization of afterloading techniques

    International Nuclear Information System (INIS)

    Anderson, L.L.

    1985-01-01

    Physical optimization in brachytherapy refers to the process of determining the radioactive-source configuration which yields a desired dose distribution. In manually afterloaded intracavitary therapy for cervix cancer, discrete source strengths are selected iteratively to minimize the sum of squares of differences between trial and target doses. For remote afterloading with a stepping-source device, optimized (continuously variable) dwell times are obtained, either iteratively or analytically, to give least squares approximations to dose at an arbitrary number of points; in vaginal irradiation for endometrial cancer, the objective has included dose uniformity at applicator surface points in addition to a tapered contour of target dose at depth. For template-guided interstitial implants, seed placement at rectangular-grid mesh points may be least squares optimized within target volumes defined by computerized tomography; effective optimization is possible only for (uniform) seed strength high enough that the desired average peripheral dose is achieved with a significant fraction of empty seed locations. (orig.) [de

  6. Treatment of unicameral bone cyst: surgical technique.

    Science.gov (United States)

    Hou, Hsien-Yang; Wu, Karl; Wang, Chen-Ti; Chang, Shun-Min; Lin, Wei-Hsin; Yang, Rong-Sen

    2011-03-01

    There is a variety of treatment modalities for unicameral bone cysts, with variable outcomes reported in the literature. Although good initial outcomes have been reported, the success rate has often changed with longer-term follow-up. We introduce a novel, minimally invasive treatment method and compare its clinical outcomes with those of other methods of treatment of this lesion. From February 1994 to April 2008, forty patients with a unicameral bone cyst were treated with one of four techniques: serial percutaneous steroid and autogenous bone-marrow injection (Group 1, nine patients); open curettage and grafting with a calcium sulfate bone substitute either without instrumentation (Group 2, twelve patients) or with internal instrumentation (Group 3, seven patients); or minimally invasive curettage, ethanol cauterization, disruption of the cystic boundary, insertion of a synthetic calcium sulfate bone-graft substitute, and placement of a cannulated screw to provide drainage (Group 4, twelve patients). Success was defined as radiographic evidence of a healed cyst or of a healed cyst with some defect according to the modified Neer classification, and failure was defined as a persistent or recurrent cyst that needed additional treatment. Patients who sustained a fracture during treatment were also considered to have had a failure. The outcome parameters included the radiographically determined healing rate, the time to solid union, and the total number of procedures needed. The follow-up time ranged from eighteen to eighty-four months. Group-4 patients had the highest radiographically determined healing rate. Healing was seen in eleven of the twelve patients in that group compared with three of the nine in Group 1, eight of the twelve in Group 2, and six of the seven in Group 3. Group-4 patients also had the shortest mean time to union: 3.7 ± 2.3 months compared with 23.4 ± 14.9, 12.2 ± 8.5, and 6.6 ± 4.3 months in Groups 1, 2, and 3, respectively. This new

  7. [Composite digital allotransplants: surgical technique and different applications].

    Science.gov (United States)

    Casoli, V; Rousvoal, A; Zirak, C; Bakhach, J; Guimberteau, J-C

    2007-10-01

    Microsurgery and human allotransplantation progress as well as the improvement of immunosuppressive drugs actually allow the development of the composite tissue allotransplantation. One of the latest challenges in plastic surgery is to restore the anatomic and functional structures using similar tissues. Composite tissue allotransplantation will probably reach this goal. Our work is to find new surgical techniques for the reconstruction of the osteotendinous apparatus of the long digits. In this paper, we will demonstrate the surgical technique to harvest the allotransplant and its modulation in the reconstruction of various digital defects.

  8. 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

  9. Surgical Approaches to Chronic Pancreatitis: Indications and Techniques.

    Science.gov (United States)

    Dua, Monica M; Visser, Brendan C

    2017-07-01

    There are a number of surgical strategies for the treatment of chronic pancreatitis. The optimal intervention should provide effective pain relief, improve/maintain quality of life, preserve exocrine and endocrine function, and manage local complications. Pancreaticoduodenectomy was once the standard operation for patients with chronic pancreatitis; however, other procedures such as the duodenum-preserving pancreatic head resections and its variants have been introduced with good long-term results. Pancreatic duct drainage via a lateral pancreaticojejunostomy continues to be effective in ameliorating symptoms and expediting return to normal lifestyle in many patients. This review summarizes operative indications and gives an overview of the different surgical strategies in treating chronic pancreatitis.

  10. Optimization of Mangala Hydropower Station, Pakistan, using Optimization Techniques

    Directory of Open Access Journals (Sweden)

    Zaman Muhammad

    2017-01-01

    Full Text Available Hydropower generation is one of the key element in the economy of a country. The present study focusses on the optimal electricity generation from the Mangla reservoir in Pakistan. A mathematical model has been developed for the Mangla hydropower station and particle swarm and genetic algorithm optimization techniques were applied at this model for optimal electricity generation. Results revealed that electricity production increases with the application of optimization techniques at the proposed mathematical model. Genetic Algorithm can produce maximum electricity than Particle swarm optimization but the time of execution of particle swarm optimization is much lesser than the Genetic algorithm. Mangla hydropower station can produce up to 59*109 kWh electricity by using the flows optimally than 47*108 kWh production from traditional methods.

  11. Some Observations on Veterinary Undergraduate Training in Surgical Techniques.

    Science.gov (United States)

    Whittick, William G.

    1978-01-01

    The undergraduate surgery course of the Faculty of Veterinary Medicine and Animal Science, Universiti Pertanian Malaysia, is described with focus on its experential method of teaching surgical techniques. Also discussed are the benefits of veterinary school cooperation with a large city Society for the Prevention of Cruelty to Animals (SPCA). (JMD)

  12. Optimal primary surgical treatment for advanced epithelial ovarian cancer.

    Science.gov (United States)

    Elattar, Ahmed; Bryant, Andrew; Winter-Roach, Brett A; Hatem, Mohamed; Naik, Raj

    2011-08-10

    Ovarian cancer is the sixth most common cancer among women. In addition to diagnosis and staging, primary surgery is performed to achieve optimal cytoreduction (surgical efforts aimed at removing the bulk of the tumour) as the amount of residual tumour is one of the most important prognostic factors for survival of women with epithelial ovarian cancer. An optimal outcome of cytoreductive surgery remains a subject of controversy to many practising gynae-oncologists. The Gynaecologic Oncology group (GOG) currently defines 'optimal' as having residual tumour nodules each measuring 1 cm or less in maximum diameter, with complete cytoreduction (microscopic disease) being the ideal surgical outcome. Although the size of residual tumour masses after surgery has been shown to be an important prognostic factor for advanced ovarian cancer, it is unclear whether it is the surgical procedure that is directly responsible for the superior outcome that is associated with less residual disease. To evaluate the effectiveness and safety of optimal primary cytoreductive surgery for women with surgically staged advanced epithelial ovarian cancer (stages III and IV).To assess the impact of various residual tumour sizes, over a range between zero and 2 cm, on overall survival. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 3) and the Cochrane Gynaecological Cancer Review Group Trials Register, MEDLINE and EMBASE (up to August 2010). We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included studies and contacted experts in the field. Retrospective data on residual disease from randomised controlled trials (RCTs) or prospective and retrospective observational studies which included a multivariate analysis of 100 or more adult women with surgically staged advanced epithelial ovarian cancer and who underwent primary cytoreductive surgery followed by adjuvant platinum

  13. Standardization of surgical techniques used in facial bone contouring.

    Science.gov (United States)

    Lee, Tae Sung

    2015-12-01

    Since the introduction of facial bone contouring surgery for cosmetic purposes, various surgical methods have been used to improve the aesthetics of facial contours. In general, by standardizing the surgical techniques, it is possible to decrease complication rates and achieve more predictable surgical outcomes, thereby increasing patient satisfaction. The technical strategies used by the author to standardize facial bone contouring procedures are introduced here. The author uses various pre-manufactured surgical tools and hardware for facial bone contouring. During a reduction malarplasty or genioplasty procedure, double-bladed reciprocating saws and pre-bent titanium plates customized for the zygomatic body, arch and chin are used. Various guarded oscillating saws are used for mandibular angloplasty. The use of double-bladed saws and pre-bent plates to perform reduction malarplasty reduces the chances of post-operative asymmetry or under- or overcorrection of the zygoma contours due to technical faults. Inferior alveolar nerve injury and post-operative jawline asymmetry or irregularity can be reduced by using a guarded saw during mandibular angloplasty. For genioplasty, final placement of the chin in accordance with preoperative quantitative analysis can be easily performed with pre-bent plates, and a double-bladed saw allows more procedural accuracy during osteotomies. Efforts by the surgeon to avoid unintentional faults are key to achieving satisfactory results and reducing the incidence of complications. The surgical techniques described in this study in conjunction with various in-house surgical tools and modified hardware can be used to standardize techniques to achieve aesthetically gratifying outcomes. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. Innovative Surgical Management of the Synovial Chondromatosis of Temporo-Mandibular Joints: Highly Conservative Surgical Technique.

    Science.gov (United States)

    Ionna, Franco; Amantea, Massimiliano; Mastrangelo, Filiberto; Ballini, Andrea; Maglione, Maria Grazia; Aversa, Corrado; De Cecio, Rossella; Russo, Daniela; Marrelli, Massimo; Tatullo, Marco

    2016-07-01

    Synovial chondromatosis (SC) is an uncommon disease characterized by a benign nodular cartilaginous proliferation arising from the joint synovium, bursae, or tendon sheaths. Although the temporomandibular joint is rarely affected by neoplastic lesions, SC is the most common neoplastic lesion of this joint. The treatment of this disease consists in the extraoral surgery with a wide removal of the lesion; in this study, the authors described a more conservative intraoral surgical approach. Patient with SC of temporomandibular joint typically refer a limitation in the mouth opening, together with a persistent not physiological mandibular protrusion and an appearance of a neoformation located at the right preauricular region: the authors reported 1 scholar patient. After biopsy of the neoformation, confirming the synovial chondromatosis, the patient underwent thus to the surgical excision of the tumor, via authors' conservative transoral approach, to facilitate the enucleation of the neoformation. The mass fully involved the pterygo-maxillary fossa with involvement of the parotid lodge and of the right TMJ: this multifocal extension suggested for a trans-oral surgical procedure, in the light of the suspicion of a possible malignant nature of the neoplasm. Our intraoral conservative approach to surgery is aimed to reduce the presence of unaesthetic scars in preauricular and facial regions, with surgical results undoubtedly comparable to the traditional surgical techniques much more aggressive. Our technique could be a valid, alternative, and safe approach to treat this rare and complex kind of oncological disease.

  15. Nonpenetrating glaucoma surgery with goniosynechiolysis ab interno: a surgical technique.

    Science.gov (United States)

    Mirshahi, A; Scharioth, G B

    2009-01-01

    To present a surgical technique for treatment of peripheral anterior synechiae (PAS or goniosynechiae) at the operative field during nonpenetrating glaucoma surgery. After usual preparation of a superficial and a deep scleral flap with externalization of the Schlemm's canal and peeling the juxtacanalicular trabecular meshwork, the goniosynechia is transected by a spatula introduced to the anterior chamber through a paracentesis. A Descemet's window provides full visual control at the peripheral cornea at the basis of the superficial scleral flap. With this surgical technique, selective treatment of goniosynechiae is possible exactly at the area where creation of low outflow resistance is intended by the surgeon during nonpenetrating glaucoma surgery. This technique enables the surgeon to perform nonpenetrating glaucoma surgery even in the presence of peripheral anterior synechiae.

  16. Surgical techniques for treatment of gastroesophageal reflux disease

    Directory of Open Access Journals (Sweden)

    Carlos Édder de Mello Cardoso Lima

    2015-12-01

    Full Text Available Gastroesophageal reflux is one of the most frequently gastrointestinal tract diseases currently found, having a great impact on the patient's quality of life. Purpose: to analyze the main surgical techniques used in the treatment of this pathology, their indications, advantages and disadvantages. Methods: this is a literature review. Thirteen articles published between 1998 and 2013 in the Lilacs, Bireme e Scielo databases, addressing different surgical techniques for the treatment of gastroesophageal reflux were selected. Results: Five hundred and thirty-eight total fundoplications and 466 partial fundoplications were performed. Conclusion: The findings of this review show that total fundoplication is the most commonly used technique in the treatment of gastroesophageal reflux disease.

  17. Restoring accommodation: surgical technique and preliminary evaluation in rabbits

    Science.gov (United States)

    Tahi, Hassan; Chapon, Pascal F.; Hamaoui, Marie; Lee, William E.; Holden, Brien; Parel, Jean-Marie A.

    1999-06-01

    Purpose. To evaluate an innovative surgical technique for phaco-ersatz, a cataract surgery designed to restore accommodation. Techniques for very small capsulorhexis as well as the refilling procedure were developed. This study evaluates the feasibility and reproducibility of the surgical technique. Methods. The right eye of 8 NZW rabbits (~ 2 Kg) were operated following the ARVO Statements for the Use of Animals in Ophthalmic and Vision Research. The surgery is begun by making a small peripheral capsulorhexis of about 1 mm using. The lens content is then removed. The lens is then refilled with a novel in situ polymerizable gel and the corneal incision is closed using one 10/0 Nylon interrupted stitch. Results. The capsulorhexis technique was succesfully performed and reproducible in all animals. The average size of the capsulorhexis opening was 1. 2 mm (+/-0.14). Lens material removal and refilling of the capsular bag with an in situ polymerizable material was also performed in each trial study. Conclusion. This surgical technique seemed feasible and reproducible.

  18. Review of Surgical Techniques of Experimental Renal Transplantation in Rats.

    Science.gov (United States)

    Shrestha, Badri; Haylor, John

    2017-08-01

    Microvascular surgical techniques of renal transplant in rats have evolved over the past 5 decades to achieve successful rat renal transplant; these modifications have included surgical techniques to address the anatomic variations in the renal blood vessels and those to reduce ischemic and operation durations. Here, we review the surgical techniques of renal transplant in rats and evaluate the advantages and disadvantages of individual techniques of vascular and ureteric anastomoses. For this review, we performed a systematic literature search using relevant medical subject heading terms and included appropriate publications in the review. Since the first description of a rat model of renal transplant by Bernard Fisher and his colleagues in 1965, which used end-to-side anastomosis between the renal vein and renal artery to the recipient inferior vena cava and aorta, several vascular and ureteric anastomosis techniques have been modified. Vascular anastomosis techniques now include end-to-end anastomosis, use of donor aortic and inferior vena cava conduits, sleeve and cuff anastomoses, and application of fibrin glue. Likewise, restoration of the urinary tract can now be achieved by direct anastomosis of the donor ureter to the recipient bladder, end-to-end anastomosis between the donor and recipient ureters, and donor bladder cuff to the recipient bladder. There are advantages and disadvantages attributable to individual techniques. The range of vascular and ureteric anastomosis techniques that has emerged reflects the need for mastering more than one technique to suit the vascular anatomy of individual animals and to reduce operating time for achieving successful outcomes after renal transplant.

  19. [Intestinal stomas--indications, stoma types, surgical technique].

    Science.gov (United States)

    Renzulli, P; Candinas, D

    2007-09-01

    The formation of an intestinal stoma is one of the most frequent operations in visceral surgery. Despite new operative techniques and a more restrictive use of the stoma, the stoma formation remains an often necessary surgical procedure, which results to a dramatic change in the patients' life. The stoma formation and its later closure are associated with a high morbidity. Many complications, such as stoma necrosis, stoma retraction or stoma prolapse, are related to surgical mistakes made during stoma formation. These complications are therefore largely avoidable. The stoma formation needs careful planning together with a professional stoma nursing team. Moreover, it is mandatory that the stoma formation is made with great care and that it meticulously follows the well established surgical principles. A perfectly placed, technically correctly fashioned and easy to care for stoma is essential for a good patients'quality of life.

  20. Surgical dislocation of the hip in patients with femoroacetabular impingement: Surgical techniques and our experience

    Directory of Open Access Journals (Sweden)

    Mladenović Marko

    2015-01-01

    Full Text Available Background/Aim. Arthrosis of the hip is the most common cause of a hip joint disorders. The aim of this study was to present our experience in the application of a safe surgical dislocation of the hip in patients with minor morphological changes in the hip joint, which, through the mechanism of femoroacetabular impingement, cause damage to the acetabular labrum and adjacent cartilage as an early sign of the hip arthrosis. Methods. We have operated 51 patients with different morphological bone changes in the hip area and resultant soft tissue damage of the acetabular labrum and its adjacent cartilage. Surgical technique that we applied in this group of patients, was adapted to our needs and capabilities and it was minimaly modified compared to the original procedure. Results. The surgical technique presented in this paper, proved to be a good method of treatment of bone and soft tissue pathomorphological changes of the hip in patients with femoroacetabular impingement. We had no cases with avascular necrosis of the femoral head, and two patients had nonunion of the greater trochanter, 9 patients developed paraarticular ossification, without subjective symptoms, while 3 patients suffered from postoperative pain in the groin during more energetic physical activities. Conclusion. Utilization of our partly modified surgical technique of controlled and safe dislocation of the hip can solve all the bone and soft tissue problems in patients with femoroacetibular impingement to stop already developed osteoarthritis of the hip or to prevent mild form of it.

  1. [Pictures balance for optimal surgical management of pelvic endometriosis. Imaging and surgery of endometriosis].

    Science.gov (United States)

    Leroy, A; Garabedian, C; Fourquet, T; Azaïs, H; Merlot, B; Collinet, P; Rubod, C

    2016-03-01

    Endometriosis is a frequent benign pathology that is found in 10-15% of women and in 20% of infertile women. It has an impact on fertility, but also in everyday life. If medical treatment fails, surgical treatment can be offered to the patient. To provide adequate treatment and give clearer information to patients, it seems essential to achieve an optimal preoperative imaging assessment. Thus, the aim of this work is to define the information expected by the surgeon and the indications of each imaging test for each compartment of the pelvis, allowing an ideal surgical management of pelvic endometriosis. We will not discuss imaging techniques' principles and we will not develop the indications and surgical techniques. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. Safe surgical technique: intramedullary nail fixation of tibial shaft fractures.

    Science.gov (United States)

    Zelle, Boris A; Boni, Guilherme

    2015-01-01

    Statically locked, reamed intramedullary nailing remains the standard treatment for displaced tibial shaft fractures. Establishing an appropriate starting point is a crucial part of the surgical procedure. Recently, suprapatellar nailing in the semi-extended position has been suggested as a safe and effective surgical technique. Numerous reduction techiques are available to achieve an anatomic fracture alignment and the treating surgeon should be familiar with these maneuvers. Open reduction techniques should be considered if anatomic fracture alignment cannot be achieved by closed means. Favorable union rates above 90 % can be achieved by both reamed and unreamed intramedullary nailing. Despite favorable union rates, patients continue to have functional long-term impairments. In particular, anterior knee pain remains a common complaint following intramedullary tibial nailing. Malrotation remains a commonly reported complication after tibial nailing. The effect of postoperative tibial malalignment on the clinical and radiographic outcome requires further investigation.

  3. THD Doppler procedure for hemorrhoids: the surgical technique

    OpenAIRE

    Ratto, C.

    2013-01-01

    Transanal hemorrhoidal dearterialization (THD) is an effective treatment for hemorrhoidal disease. The ligation of hemorrhoidal arteries (called “dearterialization”) can provide a significant reduction of the arterial overflow to the hemorrhoidal piles. Plication of the redundant rectal mucosa/submucosa (called “mucopexy”) can provide a repositioning of prolapsing tissue to the anatomical site. In this paper, the surgical technique and perioperative patient management are illustrated. Followi...

  4. Preoperative Optimization of Total Joint Arthroplasty Surgical Risk: Obesity.

    Science.gov (United States)

    Fournier, Matthew N; Hallock, Justin; Mihalko, William M

    2016-08-01

    Obesity is a problem that is increasing in prevalence in the United States and in other countries, and it is a common comorbidity in patients seeking total joint arthroplasty for degenerative musculoskeletal diseases. Obesity, as well as commonly associated comorbidities such as diabetes mellitus, cardiovascular disease, and those contributing to the diagnosis of metabolic syndrome, have been shown to have detrimental effects on total joint arthroplasty outcomes. Although there are effective surgical and nonsurgical interventions which can result in weight loss in these patients, concomitant benefit on arthroplasty outcomes is not clear. Preoperative optimization of surgical risk in obese total joint arthroplasty patients is an important point of intervention to improve arthroplasty outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. The Kock pouch reconsidered: an alternative surgical technique.

    Science.gov (United States)

    Crawshaw, Alison; Williams, Julia; Woodhouse, Fran

    The psychological impact stoma surgery can have on an individual is well documented within the literature (White and Hunt, 1997; Borwell, 2009; Williams, 2005; Brown, 2005). For many years, surgeons have explored and developed innovations in surgical techniques, in particular restorative procedures with a view of preventing permanent stoma formation; ileal anal pouch (IAP) now being the surgical procedure of choice for treatment of ulcerative colitis (UC) and familial adenomatous polyposis (FAP). However, high morbidity rates are associated with pouch longevity (Castillo et al 2005; Nessar and Wu, 2012) and once removed can lead to a high-output ileostomy with risks of electrolyte imbalance and malabsorption. This then creates the dilemma of whether the Kock pouch (KP) should be offered as a surgical option. This article offers a historical perspective of the KP and its place in the surgical management of UC and FAP. This article also presents results from a recent audit funded by the Ileostomy Association (IA), highlighting how patients manage their KP and the importance of maintaining bowel control and being free of an incontinent stoma as a means of coming to terms with their condition.

  6. 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.

  7. Outcome of Vaginoplasty in Male-to-Female Transgenders: A Systematic Review of Surgical Techniques.

    Science.gov (United States)

    Horbach, Sophie E R; Bouman, Mark-Bram; Smit, Jan Maerten; Özer, Müjde; Buncamper, Marlon E; Mullender, Margriet G

    2015-06-01

    Gender reassignment surgery is the keystone of the treatment of transgender patients. For male-to-female transgenders, this involves the creation of a neovagina. Many surgical methods for vaginoplasty have been opted. The penile skin inversion technique is the method of choice for most gender surgeons. However, the optimal surgical technique for vaginoplasty in transgender women has not yet been identified, as outcomes of the different techniques have never been compared. With this systematic review, we aim to give a detailed overview of the published outcomes of all currently available techniques for vaginoplasty in male-to-female transgenders. A PubMed and EMBASE search for relevant publications (1995-present), which provided data on the outcome of techniques for vaginoplasty in male-to-female transgender patients. Main outcome measures are complications, neovaginal depth and width, sexual function, patient satisfaction, and improvement in quality of life (QoL). Twenty-six studies satisfied the inclusion criteria. The majority of these studies were retrospective case series of low to intermediate quality. Outcome of the penile skin inversion technique was reported in 1,461 patients, bowel vaginoplasty in 102 patients. Neovaginal stenosis was the most frequent complication in both techniques. Sexual function and patient satisfaction were overall acceptable, but many different outcome measures were used. QoL was only reported in one study. Comparison between techniques was difficult due to the lack of standardization. The penile skin inversion technique is the most researched surgical procedure. Outcome of bowel vaginoplasty has been reported less frequently but does not seem to be inferior. The available literature is heterogeneous in patient groups, surgical procedure, outcome measurement tools, and follow-up. Standardized protocols and prospective study designs are mandatory for correct interpretation and comparability of data. © 2015 International Society for

  8. Surgical techniques and radiological findings of meniscus allograft transplantation.

    Science.gov (United States)

    Lee, Hoseok; Lee, Sang Yub; Na, Young Gon; Kim, Sung Kwan; Yi, Jae Hyuck; Lim, Jae Kwang; Lee, So Mi

    2016-08-01

    Meniscus allograft transplantation has been performed over the past 25 years to relieve knee pain and improve knee function in patients with an irreparable meniscus injury. The efficacy and safety of meniscus allograft transplantation have been established in numerous experimental and clinical researches. However, there is a lack of reviews to aid radiologists who are routinely interpreting images and evaluating the outcome of the procedures, and also meniscus allograft transplantation is not widely performed in most hospitals. This review focuses on the indications of the procedure, the different surgical techniques used for meniscus allograft transplantation according to the involvement of the lateral and medial meniscus, and the associated procedures. The postoperative radiological findings and surgical complications of the meniscus allograft transplantation are also described in detail. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. ACL Surgical Technique — Staying Out of Trouble

    Directory of Open Access Journals (Sweden)

    Predescu Vlad

    2016-11-01

    Full Text Available The incidence of ACL tear and reconstruction has increased over time, and failure of ACL reconstruction is not perfectly defined among surgeons. Atraumatic failure of ACL surgery represents approximately 70% of causes, and occurs in diagnostic errors, technical errors and problems of ACL graft integrations. Regarding surgical technique, we should answer certain questions about our choice of surgery, tunnel position, graft type, graft suture, tensioning the graft, and how we deal with certain incidents or intraoperative accidents. The purpose of this article is to review the current information and trends of ACL reconstruction, and presents some tips and tricks we use in our current practice.

  10. Efficient reanalysis techniques for robust topology optimization

    DEFF Research Database (Denmark)

    Amir, Oded; Sigmund, Ole; Lazarov, Boyan Stefanov

    2012-01-01

    efficient robust topology optimization procedures based on reanalysis techniques. The approach is demonstrated on two compliant mechanism design problems where robust design is achieved by employing either a worst case formulation or a stochastic formulation. It is shown that the time spent on finite...

  11. A new plastic surgical technique for adult congenital webbed penis

    Science.gov (United States)

    Chen, Yue-bing; Ding, Xian-fan; Luo, Chong; Yu, Shi-cheng; Yu, Yan-lan; Chen, Bi-de; Zhang, Zhi-gen; Li, Gong-hui

    2012-01-01

    Objective: To introduce a novel surgical technique for correction of adult congenital webbed penis. Methods: From March 2010 to December 2011, 12 patients (age range: 14–23 years old) were diagnosed as having a webbed penis and underwent a new surgical procedure designed by us. Results: All cases were treated successfully without severe complication. The operation time ranged from 20 min to 1 h. The average bleeding volume was less than 50 ml. All patients achieved satisfactory cosmetic results after surgery. The penile curvature disappeared in all cases and all patients remained well after 1 to 3 months of follow-up. Conclusions: Adult webbed penis with complaints of discomfort or psychological pressure due to a poor profile should be indicators for surgery. Good corrective surgery should expose the glans and coronal sulcus, match the penile skin length to the penile shaft length dorsally and ventrally, and provide a normal penoscrotal junction. Our new technique is a safe and effective method for the correction of adult webbed penis, which produces satisfactory results. PMID:22949367

  12. [Surgical closure of patent ductus arteriosus in premature neonates: Does the surgical technique affect the outcome?

    Science.gov (United States)

    Avila-Alvarez, Alejandro; Serantes Lourido, Marta; Barriga Bujan, Rebeca; Blanco Rodriguez, Carolina; Portela-Torron, Francisco; Bautista-Hernandez, Victor

    2017-05-01

    Surgical closure of patent ductus arteriosus in premature neonates is an aggressive technique and is not free of complications. A study was designed with the aim of describing our experience with a less invasive technique, the extra-pleural approach via a posterior minithoracotomy, and to compare the results with the classic transpleural approach. A retrospective cohort study was conducted on premature neonates on whom surgical closure of the ductus was performed during a ten-year period (March 2005 to March 2015). A comparison was made of the acute complications, the outcomes on discharge, and follow-up, between the extra-pleural approach and the classic transpleural approach. The study included 48 patients, 30 in the classical approach and 18 in the extra-pleural group. The demographic and pre-operative characteristics were similar in both groups. No differences were found between the 2 groups in the incidence of acute post-operative complications (56.6 vs. 44.4%), on the dependence on oxygen at 36 weeks (33.3 vs. 55.5%), or in hospital mortality (10 vs. 16.6%). As regards the short-term progress, the extra-pleural group required fewer days until the withdrawal of supplementary oxygen (36.3 vs. 28.9) and until hospital discharge (67.5 vs. 53.2), although only the time until extubation achieved a statistically significant difference (11.5 vs. 2.7, P=.03). The extra-plural approach by posterior minithoracotomy for the surgical closure of ductus in the premature infant is viable and could bring some clinical benefits in the short-term. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Software for the grouped optimal aggregation technique

    Science.gov (United States)

    Brown, P. M.; Shaw, G. W. (Principal Investigator)

    1982-01-01

    The grouped optimal aggregation technique produces minimum variance, unbiased estimates of acreage and production for countries, zones (states), or any designated collection of acreage strata. It uses yield predictions, historical acreage information, and direct acreage estimate from satellite data. The acreage strata are grouped in such a way that the ratio model over historical acreage provides a smaller variance than if the model were applied to each individual stratum. An optimal weighting matrix based on historical acreages, provides the link between incomplete direct acreage estimates and the total, current acreage estimate.

  14. Fusion blanket design and optimization techniques

    International Nuclear Information System (INIS)

    Gohar, Y.

    2005-01-01

    In fusion reactors, the blanket design and its characteristics have a major impact on the reactor performance, size, and economics. The selection and arrangement of the blanket materials, dimensions of the different blanket zones, and different requirements of the selected materials for a satisfactory performance are the main parameters, which define the blanket performance. These parameters translate to a large number of variables and design constraints, which need to be simultaneously considered in the blanket design process. This represents a major design challenge because of the lack of a comprehensive design tool capable of considering all these variables to define the optimum blanket design and satisfying all the design constraints for the adopted figure of merit and the blanket design criteria. The blanket design techniques of the First Wall/Blanket/Shield Design and Optimization System (BSDOS) have been developed to overcome this difficulty and to provide the state-of-the-art techniques and tools for performing blanket design and analysis. This report describes some of the BSDOS techniques and demonstrates its use. In addition, the use of the optimization technique of the BSDOS can result in a significant blanket performance enhancement and cost saving for the reactor design under consideration. In this report, examples are presented, which utilize an earlier version of the ITER solid breeder blanket design and a high power density self-cooled lithium blanket design for demonstrating some of the BSDOS blanket design techniques

  15. Computational optimization techniques applied to microgrids planning

    DEFF Research Database (Denmark)

    Gamarra, Carlos; Guerrero, Josep M.

    2015-01-01

    Microgrids are expected to become part of the next electric power system evolution, not only in rural and remote areas but also in urban communities. Since microgrids are expected to coexist with traditional power grids (such as district heating does with traditional heating systems......), their planning process must be addressed to economic feasibility, as a long-term stability guarantee. Planning a microgrid is a complex process due to existing alternatives, goals, constraints and uncertainties. Usually planning goals conflict each other and, as a consequence, different optimization problems...... appear along the planning process. In this context, technical literature about optimization techniques applied to microgrid planning have been reviewed and the guidelines for innovative planning methodologies focused on economic feasibility can be defined. Finally, some trending techniques and new...

  16. THD Doppler procedure for hemorrhoids: the surgical technique.

    Science.gov (United States)

    Ratto, C

    2014-03-01

    Transanal hemorrhoidal dearterialization (THD) is an effective treatment for hemorrhoidal disease. The ligation of hemorrhoidal arteries (called "dearterialization") can provide a significant reduction of the arterial overflow to the hemorrhoidal piles. Plication of the redundant rectal mucosa/submucosa (called "mucopexy") can provide a repositioning of prolapsing tissue to the anatomical site. In this paper, the surgical technique and perioperative patient management are illustrated. Following adequate clinical assessment, patients undergo THD under general or spinal anesthesia, in either the lithotomy or the prone position. In all patients, distal Doppler-guided dearterialization is performed, providing the selective ligation of hemorrhoidal arteries identified by Doppler. In patients with hemorrhoidal/muco-hemorrhoidal prolapse, the mucopexy is performed with a continuous suture including the redundant and prolapsing mucosa and submucosa. The description of the surgical procedure is complemented by an accompanying video (see supplementary material). In long-term follow-up, there is resolution of symptoms in the vast majority of patients. The most common complication is transient tenesmus, which sometimes can result in rectal discomfort or pain. Rectal bleeding occurs in a very limited number of patients. Neither fecal incontinence nor chronic pain should occur. Anorectal physiology parameters should be unaltered, and anal sphincters should not be injured by following this procedure. When accurately performed and for the correct indications, THD is a safe procedure and one of the most effective treatments for hemorrhoidal disease.

  17. A Brief Recap of Tips and Surgical Manoeuvres to Enhance Optimal Outcome of Surgically Placed Peritoneal Dialysis Catheters

    Directory of Open Access Journals (Sweden)

    Jodie H. Frost

    2012-01-01

    Full Text Available Background. Peritoneal dialysis (PD is an effective option of renal replacement therapy for ESRF, offering advantages over haemodialysis. Peritoneal dialysis catheter (PDC placement is thought to be the key to successful PD and the economic advantages are lost if a patient switches to HD in the 1st year. This paper is a brief document elaborating a recap of published literature, looking at various surgical tips and manoeuvres to enhance optimal outcome of PDC placement. Methods. A search strategy assessing for access team, preoperative antibiotic prophylaxis, type of catheter, catheter exit site, intraoperative catheter trial, optimal time to commence PD, hernia repairs, number of cuffs, catheter-embedding procedures, rectus sheath tunnelling, laparoscopic fixing, omentopexy, omentectomy, the “Y”-Tec system, resection of epiploic appendages, adhesiolysis, a trained surgeon, and perioperative catheter care protocol was used looking at various databases. Findings. The complications of catheterrelated dysfunction can be reduced with advanced planning of access placement, immaculate surgery, and attention to catheter insertion techniques. Conclusion. The success of a peritoneal dialysis programme depends upon functional and durable long term access to the peritoneal cavity; this depends on placement techniques and competent surgeons and psychosocial support to the patient. The various technical tips and manoeuvres elaborated here should be considered options carried out to improve outcome and reduce catheter dysfunction.

  18. Gynecomastia associated with herniated nipples: an optimal surgical approach.

    Science.gov (United States)

    Jaiswal, Rohit; Pu, Lee L Q

    2012-04-01

    Gynecomastia is a common disorder observed in male plastic surgery patients. Treatment options may include observation, surgical excision, or liposuction techniques. Congenital herniated nipple is a more rare condition, especially in male patients. We present the case of a 12-year-old boy with bilateral gynecomastia and herniated nipple-areolar complexes. A staged repair was undertaken in this patient with grade 2 gynecomastia. The first operation was ultrasonic liposuction bilaterally, yielding 200 mL of aspirate from the left and 400 mL on the right, to correct the gynecomastia. The second procedure, performed 6 months later, was a bilateral periareolar mastopexy to repair the herniated nipple-areolar complexes. The result of the first procedure was flattened and symmetrical breast tissue bilaterally, essentially a correction of the gynecomastia. The herniated nipples were still present, however. Bilateral periareolar mastopexies were then performed with resulting reduction of the herniations. There were no complications with either procedure, and a good cosmetic result was achieved. A staged surgical approach was successful in correcting both conditions with an excellent aesthetic result and the advantage of decreased risk for nipple complications.

  19. [Minimally invasive surgical therapy of gynecomastia: liposuction and exeresis technique].

    Science.gov (United States)

    Voigt, M; Walgenbach, K J; Andree, C; Bannasch, H; Looden, Z; Stark, G B

    2001-10-01

    A number of techniques are available for the correction of gynecomastia. Nonscarring sparing methods are preferred, and the minimally invasive technique is to use liposuction for the gland and the fatty tissue exclusively. In this retrospective study we present our experience with a combination of liposuction and subsequent resection of the remaining gland. Sixty-two patients (112 breasts) were surgically treated for gynecomastia from January 1996 and September 2000. From 1996 to 1997 all patients suffering from gynecomastia grade Simon I-II were treated by the method described by Rosenberg and Stark, which is exclusively suction of the fatty and glandular tissue. In a retrospective chart study a high recurrence rate was found in these patients. Subsequently we changed our technique to liposuction of the fatty tissue followed by sharp excision of the glandular tissue through the incision made for the liposuction cannula in the submammary fold. Suction alone was not sufficient to remove the glandular tissue; the rate of recurrence after suction was 35%. When sharp resection of the glandular tissue was carried out after the liposuction the recurrence rate dropped to under 10%. In total our complication rate was 50% including minor sequelae. The most frequent complication was unacceptable scarring of the nipple-areola complex. Hypesthesia of the nipple-areola occurred in 13.4% of the patients. The combination of liposuction and resection of the glandular tissue is a minimally invasive correction that can be used in all cases of gynecomastia grade Simon I-II.

  20. Surgical techniques for the atomic bomb survivors of thyroid cancer

    International Nuclear Information System (INIS)

    Takeichi, Nobuo; Dohi, Kiyohiko; Noso, Yoshihiro

    2016-01-01

    As for proper surgical techniques for radiation-induced thyroid carcinogenesis, this paper explains with a focus on the Hiroshima University cases, with an addition of the cases of Radiation Effects Research Foundation and Takeichi Clinic. The definitive diagnosis of thyroid cancer is usually carried out by echo-guided aspiration biopsy cytology, but Takeichi Clinic faces the surgery by preparing 'thyroid - cervical lymph node map' by combining this technique with CT and MRI. As the surgery examples at Hiroshima University, 259 cases during 1955-1972 and 363 cases during 1965-1982 were taken up, and the survival rate and cancer death rate classified by tissue types for 10 years after the initial operations were shown in a table. Dead patients were mostly the surgery cases of senior persons of 60 years in age or older, and the death rate for surgery cases of the persons of 19 years old or younger was only 1.9% at 6 cases. Higher cancer death rate was seen in the cases of papillary cancer of more than 5 cm in size, where extra glandular infiltration could not be curated or cut out, and 64/318 cases of patients had a recurrence of cancer at thyroid gland. The mortality rate up to 20 years after the surgery of atomic bomb survivors was not significantly different from that of non-victims. Information on the multicentric cancerous focuses and microscopic cancer in the thyroid gland, as well as the tissue types and high risk of cancer death were described from the cases of Hiroshima University and Takeichi Clinic. The thyroid cancer of radiation exposure victims often results in papillary cancer, and the following are described related with this: (1) selection of ablation method, (2) method to protect the parathyroid tissue, and (3) method to prevent damage to the recurrent laryngeal nerve and superior laryngeal nerve. The surgical procedure to perform the neck outside area lymph node dissection due to the quasi-subtotal or quasi-complete removal of the thyroid gland is

  1. Ontogeny of a surgical technique: Robotic kidney transplantation with regional hypothermia.

    Science.gov (United States)

    Sood, Akshay; McCulloch, Peter; Dahm, Philipp; Ahlawat, Rajesh; Jeong, Wooju; Bhandari, Mahendra; Menon, Mani

    2016-01-01

    Innovation is a hallmark of surgical practice. It is generally accepted that a new procedure will undergo technical changes during its evolution; however, quantitative accounts of the process are limited. Multiple groups, including our own, have recently described a minimally-invasive approach to conventional kidney transplantation (KT) operation. Unique to our experience is a structured development of the technique within the confines of a safe surgical innovation framework - the IDEAL framework (idea, development, exploration, assessment, long-term monitoring; stages 0-4). We here provide a first-hand narrative of the progress of robotic KT operation from preclinical trial to clinical application. Overall, 54 patients underwent robotic KT with regional hypothermia successfully. Major technical changes including selection of optimal patient position (flank vs. lithotomy), robotic instrumentation, vascular occlusion method (bulldog vs. tourniquet) and suture material (prolene vs. GoreTex) occurred early during the procedure development (IDEAL stage 0, preclinical). Minor technical changes such as utilization of the aortic punch for arteriotomy (case 3), use of barbed suture during ureteroneocystostomy (case 6) and extraperitonealization of the graft kidney (case 6) that increased the efficiency and safety of the procedure continued throughout procedure development (IDEAL stages 1-2, clinical stages). We demonstrate that a surgical technique evolves continually; although, the majority of technical alterations occur early in the life-cycle of the procedure. Development of a new technique within the confines a structured surgical innovation framework allows for evidence based progression of the technique and may minimize the risk of harm to the patient. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

  2. [Endoscopic calcaneoplasty (ECP) in Haglund's syndrome. Indication, surgical technique, surgical findings and results].

    Science.gov (United States)

    Jerosch, J; Sokkar, S; Dücker, M; Donner, A

    2012-06-01

    Posterior calcaneal exostosis treatment modalities have given rise to many controversial opinions. After failure of the conservative treatment, surgical bursectomy and resection of the calcaneal exostosis are indicated by many authors. But clinical studies also show a high rate of unsatisfactory results with a relative high incidence of complications. The minimally invasive surgical technique by an endoscopic calcaneoplasty (ECP) could be an option to overcome some of these problems. Between 1999 und 2010 we operated 164 patients with an age range between 16 and 67 years, 81 males and 83 females. The radiological examination prior to surgery documented in all cases a posterior superior calcaneal exostosis that showed friction to the Achilles tendon. All patients included in the study had no clinical varus of the hind foot, nor cavus deformities. All patients had undergone a trial of conservative treatment for at least 6 months and did not show a positive response. The average follow-up was 46.3 (range: 8-120) months. According to the Ogilvie-Harris score 71 patients presented good and 84 patients excellent results, while 5 patients showed fair results, and 4 patients only poor results. All the post-operative radiographs showed sufficient resection of the calcaneal spur. In 61 patients the preoperative MRI showed a partial rupture of the Achilles tendon close to the insertion side. In no case could we observe a complete tear at the time of follow-up. Only minor postoperative complications were observed. In many patients we could observe a chondral layer at the posterior aspect of the calcaneus. Close to the intersion the Achilles tendon showed also in many patients a chondroide metaplasia. ECP is an effective and minimally invasive procedure for the treatment of patients with calcaneal exostosis. After a short learning curve the endoscopic exposure is superior to the open technique, has less morbidity, less operating time, and nearly no complications. Moreover, the

  3. Innovation in surgical technology and techniques: Challenges and ethical issues.

    Science.gov (United States)

    Geiger, James D; Hirschl, Ronald B

    2015-06-01

    The pace of medical innovation continues to increase. The deployment of new technologies in surgery creates many ethical challenges including how to determine safety of the technology, what is the timing and process for deployment of a new technology, how are patients informed before undergoing a new technology or technique, how are the outcomes of a new technology evaluated and how are the responsibilities of individual patients and society at large balanced. Ethical considerations relevant to the implementation of ECMO and robotic surgery are explored to further discussion of how we can optimize the delicate balance between innovation and regulation. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Optimal surgical approach to thymic malignancies: New trends challenging old dogmas.

    Science.gov (United States)

    Ruffini, Enrico; Filosso, Pier Luigi; Guerrera, Francesco; Lausi, Paolo; Lyberis, Paraskevas; Oliaro, Alberto

    2018-04-01

    Until recently, the surgical approach to thymic tumors has remained basically unchanged. The collaborative effort led by ITMIG with the collaboration of regional and society-based interest groups (ESTS, JART) produced an enthusiastic surge of interest in testing the new technological advances in thoracic surgery and many historical dogmas in thymic surgery have been questioned and challenged. The present review addresses the new trends in the optimal surgical management of thymic tumors based on the review of the current literature. 1. Minimally-invasive techniques (MIT) including video-assisted thoracic surgery (VATS) and robotic-assisted thoracic Surgery (RATS) are now to be considered the standard of care in early-stage thymic tumors. MIT are no inferior to open approaches in terms of postoperative complications, loco-regional recurrence rates and survival. MIT are associated with a shorter length of stay, reduced intraoperative blood loss and better cosmetic results. 2. The adoption of the ITMIG/IASLC TNM staging system for thymic tumors requires a paradigm shift among thoracic surgeons to include regional lymphadenectomy according to the IASLC/ITMIG nodal map in the surgical management of thymic tumors. 3. A limited thymectomy instead of total thymectomy along with the removal of the thymic tumor in nonmyasthenic Stage I-II tumors has been proposed by some authors, although the results are not uniform. Until more mature data is available, adherence to the current guidelines recommending total thymectomy in addition to thymomectomy is always indicated. 4. In locally-advanced Stage IVa patients with pleural involvement, major pleural resections, including pleurectomy/decortication or extrapleural pneumonectomy are indicated, provided a complete resection of the pleural deposits is anticipated, usually in a multidisciplinary setting, with excellent long-term results. The incorporation of these new concepts and techniques in the surgical armamentarium of the

  5. Through Knee Amputation: Technique Modifications and Surgical Outcomes

    Directory of Open Access Journals (Sweden)

    Frank P Albino

    2014-09-01

    Full Text Available BackgroundKnee disarticulations (KD are most commonly employed following trauma or tumor resection but represent less than 2% of all lower extremity amputations performed in the United States annually. KDs provide enhanced proprioception, a long lever arm, preservation of adductor muscle insertion, decreased metabolic cost of ambulation, and an end weight-bearing stump. The role for KDs in the setting of arterial insufficiency or overwhelming infection is less clear. The purpose of this study is to describe technique modifications and report surgical outcomes following KDs at a high-volume Limb Salvage Center.MethodsA retrospective study of medical records for all patients who underwent a through-knee amputation performed by the senior author (C.E.A. between 2004 and 2012 was completed. Medical records were reviewed to collect demographic, operative, and postoperative information for each of the patients identified.ResultsBetween 2004 and 2012, 46 through-knee amputations for 41 patients were performed. The mean patient age was 68 and indications for surgery included infection (56%, arterial thrombosis (35%, and trauma (9%. Postoperative complications included superficial cellulitis (13%, soft tissue infection (4%, and flap ischemia (4% necessitating one case of surgical debridement (4% and four trans-femoral amputations (9%. 9 (22% patients went on to ambulate. Postoperative ambulation was greatest in the traumatic cohort and for patients less than 50 years of age, P<0.05. Alternatively, diabetes mellitus and infection reduced the likelihood of postoperative ambulation, P<0.01.ConclusionsKnee disarticulations are a safe and effective alternative to other lower extremity amputations when clinically feasible. For patient unlikely to ambulate, a through-knee amputation maximizes ease of transfers, promotes mobility by providing a counterbalance, and eliminates the potential for knee flexion contracture with subsequent skin breakdown.

  6. [The optimization of a surgical intervention to stabilize progressive myopia].

    Science.gov (United States)

    Gonchar, P A; Dushin, N V; Beliaev, V S; Kravchinina, V V; Barashkov, V I; Frolov, M A

    1999-01-01

    Results of 236 sclera-fortifying surgeries are followed up for more than 25 years. Progressive myopia stabilized in 95.8% cases after bandaging scleroplasty and in 87.03% cases after chondroplasty. Clinical refraction and posteroanterior axis of the eye did not increase after surgery; visual functions stabilized, and brightness sensitivity threshold was lowered. The technique of operation and clinical course of the postoperative period are described. Based on analysis of the clinical material, the authors propose the optimal approach to scleroplastic operations aimed at stabilization of progressive myopia.

  7. Surgical treatment of gynecomastia: mastectomy compared to liposuction technique.

    Science.gov (United States)

    Song, Yan-Ni; Wang, Yan-Bo; Huang, Rui; He, Xiao-Guang; Zhang, Jin-Feng; Zhang, Guo-Qiang; Ren, Yan-Lv; Pang, Jian-Hua; Pang, Da

    2014-09-01

    Gynecomastia is a benign enlargement of the male breast. Yet enlarged breasts cause anxiety, embarrassment, psychosocial discomfort, and fear of breast cancer. The aim of this study was to assess the experience of gynecomastia patients undergoing mastectomy and liposuction surgery. Seven hundred thirty-three patients were analyzed for age, chief complaint, position, grade, operation approach, biopsy, and complication between mastectomy group and liposuction group, from 1990 to 2010. Four hundred two patients (436 breasts) were treated with mastectomy and 331 patients (386 breasts) were treated with liposuction techniques. Three hundred thirty (82%) patients complained of breast lump and lump with pain in mastectomy group, and 204 (61%) patients complained of enlargement breast and enlargement with pain in liposuction group (P liposuction acquired pathologic diagnosis through fine needle aspiration and/or core biopsy (P liposuction group were 1.4% and 0.5%, respectively. There were no nipple/areola necrosis and scars in liposuction group. The surgical treatment of gynecomastia required an individual approach, depending on symptoms (lump or enlargement) and requirements of patients. Patients who chose mastectomy were looking for reassurance that their pathologic diagnosis was benign. The increase in the number of liposuction patients was reflected in our study because it was associated with superior esthetic results and few complications.

  8. Machine Learning Techniques in Optimal Design

    Science.gov (United States)

    Cerbone, Giuseppe

    1992-01-01

    Many important applications can be formalized as constrained optimization tasks. For example, we are studying the engineering domain of two-dimensional (2-D) structural design. In this task, the goal is to design a structure of minimum weight that bears a set of loads. A solution to a design problem in which there is a single load (L) and two stationary support points (S1 and S2) consists of four members, E1, E2, E3, and E4 that connect the load to the support points is discussed. In principle, optimal solutions to problems of this kind can be found by numerical optimization techniques. However, in practice [Vanderplaats, 1984] these methods are slow and they can produce different local solutions whose quality (ratio to the global optimum) varies with the choice of starting points. Hence, their applicability to real-world problems is severely restricted. To overcome these limitations, we propose to augment numerical optimization by first performing a symbolic compilation stage to produce: (a) objective functions that are faster to evaluate and that depend less on the choice of the starting point and (b) selection rules that associate problem instances to a set of recommended solutions. These goals are accomplished by successive specializations of the problem class and of the associated objective functions. In the end, this process reduces the problem to a collection of independent functions that are fast to evaluate, that can be differentiated symbolically, and that represent smaller regions of the overall search space. However, the specialization process can produce a large number of sub-problems. This is overcome by deriving inductively selection rules which associate problems to small sets of specialized independent sub-problems. Each set of candidate solutions is chosen to minimize a cost function which expresses the tradeoff between the quality of the solution that can be obtained from the sub-problem and the time it takes to produce it. The overall solution

  9. Evolutionary optimization technique for site layout planning

    KAUST Repository

    El Ansary, Ayman M.

    2014-02-01

    Solving the site layout planning problem is a challenging task. It requires an iterative approach to satisfy design requirements (e.g. energy efficiency, skyview, daylight, roads network, visual privacy, and clear access to favorite views). These design requirements vary from one project to another based on location and client preferences. In the Gulf region, the most important socio-cultural factor is the visual privacy in indoor space. Hence, most of the residential houses in this region are surrounded by high fences to provide privacy, which has a direct impact on other requirements (e.g. daylight and direction to a favorite view). This paper introduces a novel technique to optimally locate and orient residential buildings to satisfy a set of design requirements. The developed technique is based on genetic algorithm which explores the search space for possible solutions. This study considers two dimensional site planning problems. However, it can be extended to solve three dimensional cases. A case study is presented to demonstrate the efficiency of this technique in solving the site layout planning of simple residential dwellings. © 2013 Elsevier B.V. All rights reserved.

  10. Robotic partial nephrectomy for complex renal tumors: surgical technique.

    Science.gov (United States)

    Rogers, Craig G; Singh, Amar; Blatt, Adam M; Linehan, W Marston; Pinto, Peter A

    2008-03-01

    Laparoscopic partial nephrectomy requires advanced training to accomplish tumor resection and renal reconstruction while minimizing warm ischemia times. Complex renal tumors add an additional challenge to a minimally invasive approach to nephron-sparing surgery. We describe our technique, illustrated with video, of robotic partial nephrectomy for complex renal tumors, including hilar, endophytic, and multiple tumors. Robotic assistance was used to resect 14 tumors in eight patients (mean age: 50.3 yr; range: 30-68 yr). Three patients had hereditary kidney cancer. All patients had complex tumor features, including hilar tumors (n=5), endophytic tumors (n=4), and/or multiple tumors (n=3). Robotic partial nephrectomy procedures were performed successfully without complications. Hilar clamping was used with a mean warm ischemia time of 31 min (range: 24-45 min). Mean blood loss was 230 ml (range: 100-450 ml). Histopathology confirmed clear-cell renal cell carcinoma (n=3), hybrid oncocytic tumor (n=2), chromophobe renal cell carcinoma (n=2), and oncocytoma (n=1). All patients had negative surgical margins. Mean index tumor size was 3.6 cm (range: 2.6-6.4 cm). Mean hospital stay was 2.6 d. At 3-mo follow-up, no patients experienced a statistically significant change in serum creatinine or estimated glomerular filtration rate and there was no evidence of tumor recurrence. Robotic partial nephrectomy is safe and feasible for select patients with complex renal tumors, including hilar, endophytic, and multiple tumors. Robotic assistance may facilitate a minimally invasive, nephron-sparing approach for select patients with complex renal tumors who might otherwise require open surgery or total nephrectomy.

  11. Lengthening of fourth brachymetatarsia by three different surgical techniques.

    Science.gov (United States)

    Lee, W-C; Yoo, J H; Moon, J-S

    2009-11-01

    We carried out a retrospective study to assess the clinical results of lengthening the fourth metatarsal in brachymetatarsia in 153 feet of 106 patients (100 female, six males) using three different surgical techniques. In one group lengthening was performed by one-stage intercalary bone grafting secured by an intramedullary Kirschner-wire (45 feet, 35 patients). In the second group lengthening was obtained gradually using a mini-external fixator after performing an osteotomy with a saw (59 feet, 39 patients) and in the third group lengthening was achieved in a gradual manner using a mini-external fixator after undertaking an osteotomy using osteotome through pre-drilled holes (49 feet, 32 patients). The mean age of the patients was 26.3 years (13 to 48). Pre-operatively, the fourth ray of the bone-graft group was longer than that of other two groups (p lengthening in the bone-graft group was 13.9 mm (3.5 to 23.0, 27.1%) which was less than that obtained in the saw group with a mean of 17.8 mm (7.0 to 33.0, 29.9%) and in the pre-drilled osteotome group with a mean of 16.8 mm (6.5 to 28.0, 29.4%, p = 0.001). However, the mean time required for retention of the fixation in the bone-graft group was the shortest of the three groups. Patients were dissatisfied with the result for five feet (11.1%) in the bone-graft group, eight (13.6%) in the saw group and none in the pre-drilled osteotomy group (p lengthening by distraction osteogenesis after osteotomy using an osteotome produces the most reliable results for the treatment of fourth brachymetatarsia.

  12. Restoration of optimal ellipsoid left ventricular geometry: lessons learnt from in silico surgical modelling.

    Science.gov (United States)

    Adhyapak, Srilakshmi M; Menon, Prahlad G; Rao Parachuri, V

    2014-02-01

    Several issues that are inherent in the surgical techniques of surgical ventricular restoration (SVR) need specialized devices or techniques to overcome them, which may not always result in optimal outcomes. We used a non-invasive novel in silico modelling technique to study left ventricular (LV) morphology and function before and after SVR. The cardiac magnetic resonance imaging derived actual pre- and postoperative endocardial morphology and function was compared with the in silico analysis of the same. Cardiac magnetic resonance steady state free precession (SSFP) cine images were employed to segment endocardial surface contours over the cardiac cycle. Using the principle of Hausdorff distance to examine phase-to-phase regional endocardial displacement, dyskinetic/akinetic areas were identified at the instant of peak basal contraction velocity. Using a three-dimensional (3D) surface clipping tool, the maximally scarred, dyskinetic or akinetic LV antero-apical areas were virtually resected and a new apex was created. A virtual rectangular patch was created upon the clipped surface LV model by 3D Delaunay triangulation. Presurgical endocardial mechanical function quantified from cine cardiac magnetic resonance, using a technique of spherical harmonics (SPHARM) surface parameterization, was applied onto the virtually clipped and patched LV surface model. Finally, the in silico model of post-SVR LV shape was analysed for quantification of regional left ventricular volumes (RLVVs) and function. This was tested in 2 patients with post-myocardial infarction antero-apical LV aneuryms. Left ventricular mechanical dysynchrony was evaluated by RLVV analysis of pre-SVR, in silico post-SVR and actual post-SVR LV endocardial surface data. Following exclusion of the scarred areas, the virtual resected LV model demonstrated significantly lesser areas of akinesia. The decreases in regional LV volumes in the in silico modelling were significant and comparable with the actual

  13. Parallel halftoning technique using dot diffusion optimization

    Science.gov (United States)

    Molina-Garcia, Javier; Ponomaryov, Volodymyr I.; Reyes-Reyes, Rogelio; Cruz-Ramos, Clara

    2017-05-01

    In this paper, a novel approach for halftone images is proposed and implemented for images that are obtained by the Dot Diffusion (DD) method. Designed technique is based on an optimization of the so-called class matrix used in DD algorithm and it consists of generation new versions of class matrix, which has no baron and near-baron in order to minimize inconsistencies during the distribution of the error. Proposed class matrix has different properties and each is designed for two different applications: applications where the inverse-halftoning is necessary, and applications where this method is not required. The proposed method has been implemented in GPU (NVIDIA GeForce GTX 750 Ti), multicore processors (AMD FX(tm)-6300 Six-Core Processor and in Intel core i5-4200U), using CUDA and OpenCV over a PC with linux. Experimental results have shown that novel framework generates a good quality of the halftone images and the inverse halftone images obtained. The simulation results using parallel architectures have demonstrated the efficiency of the novel technique when it is implemented in real-time processing.

  14. Techniques for optimizing inerting in electron processors

    International Nuclear Information System (INIS)

    Rangwalla, I.J.; Korn, D.J.; Nablo, S.V.

    1993-01-01

    The design of an ''inert gas'' distribution system in an electron processor must satisfy a number of requirements. The first of these is the elimination or control of beam produced ozone and NO x which can be transported from the process zone by the product into the work area. Since the tolerable levels for O 3 in occupied areas around the processor are 3 in the beam heated process zone, or exhausting and dilution of the gas at the processor exit. The second requirement of the inerting system is to provide a suitable environment for completing efficient, free radical initiated addition polymerization. The competition between radical loss through de-excitation and that from O 2 quenching must be understood. This group has used gas chromatographic analysis of electron cured coatings to study the trade-offs of delivered dose, dose rate and O 2 concentrations in the process zone to determine the tolerable ranges of parameter excursions for production quality control purposes. These techniques are described for an ink coating system on paperboard, where a broad range of process parameters have been studied (D, D radical, O 2 ). It is then shown how the technique is used to optimize the use of higher purity (10-100 ppm O 2 ) nitrogen gas for inerting, in combination with lower purity (2-20,000 ppm O 2 ) non-cryogenically produced gas, as from a membrane or pressure swing adsorption generators. (author)

  15. A new technique in the surgical treatment of Hangman's fractures: Neurospinal Academy (NSA) technique.

    Science.gov (United States)

    Dalbayrak, Sedat; Yaman, Onur; Yılmaz, Mesut

    2013-07-01

    Treatment of Hangman's fractures is still controversial. Hangman's fractures Type II and IIA are usually treated with surgical procedures. This study aims at describing the Neurospinal Academy (NSA) technique as an attempt to achieve an approximation of the fracture line to the axis body, which may be used for Type II and IIA patients with severe displacement and angulation. NSA technique both pars or pedicle screws are placed bicortically to ensure that anterior surface of C2 vertebral body will be crossed 1-2 mm. A rod is prepared in suitable length and curve to connect the two screws. For placing the rod, sufficient amount of bone is resected from the C2 spinous process. C2 vertebral body is pulled back by means of the screws that crossed the anterior surface of C2 vertebral body. Hangman II and IIA patient are treated with NSA technique. Angulated and tilted C2 vertebral body was pulled back and approximated to posterior elements. In Hangman's fractures Type II and IIA with severe vertebral body and pedicle displacement, NSA technique is an effective and reliable treatment alternative for the approximation of posterior elements to the C2 vertebral body, which is tilted, angulated, and dislocated.

  16. A new technique in the surgical treatment of Hangman′s fractures: Neurospinal Academy (NSA technique

    Directory of Open Access Journals (Sweden)

    Sedat Dalbayrak

    2013-01-01

    Full Text Available Context: Treatment of Hangman′s fractures is still controversial. Hangman′s fractures Type II and IIA are usually treated with surgical procedures. Aim: This study aims at describing the Neurospinal Academy (NSA technique as an attempt to achieve an approximation of the fracture line to the axis body, which may be used for Type II and IIA patients with severe displacement and angulation. Settings and Design: NSA technique both pars or pedicle screws are placed bicortically to ensure that anterior surface of C2 vertebral body will be crossed 1-2 mm. A rod is prepared in suitable length and curve to connect the two screws. For placing the rod, sufficient amount of bone is resected from the C2 spinous process. C2 vertebral body is pulled back by means of the screws that crossed the anterior surface of C2 vertebral body. Materials and Methods: Hangman II and IIA patient are treated with NSA technique. Result: Angulated and tilted C2 vertebral body was pulled back and approximated to posterior elements. Conclusions: In Hangman′s fractures Type II and IIA with severe vertebral body and pedicle displacement, NSA technique is an effective and reliable treatment alternative for the approximation of posterior elements to the C2 vertebral body, which is tilted, angulated, and dislocated.

  17. Application of Nontraditional Optimization Techniques for Airfoil Shape Optimization

    Directory of Open Access Journals (Sweden)

    R. Mukesh

    2012-01-01

    Full Text Available The method of optimization algorithms is one of the most important parameters which will strongly influence the fidelity of the solution during an aerodynamic shape optimization problem. Nowadays, various optimization methods, such as genetic algorithm (GA, simulated annealing (SA, and particle swarm optimization (PSO, are more widely employed to solve the aerodynamic shape optimization problems. In addition to the optimization method, the geometry parameterization becomes an important factor to be considered during the aerodynamic shape optimization process. The objective of this work is to introduce the knowledge of describing general airfoil geometry using twelve parameters by representing its shape as a polynomial function and coupling this approach with flow solution and optimization algorithms. An aerodynamic shape optimization problem is formulated for NACA 0012 airfoil and solved using the methods of simulated annealing and genetic algorithm for 5.0 deg angle of attack. The results show that the simulated annealing optimization scheme is more effective in finding the optimum solution among the various possible solutions. It is also found that the SA shows more exploitation characteristics as compared to the GA which is considered to be more effective explorer.

  18. How do you tell whether a change in surgical technique leads to a change in outcome?

    Science.gov (United States)

    Vickers, Andrew J; Cronin, Angel M; Masterson, Timothy A; Eastham, James A

    2010-04-01

    Surgeons routinely evaluate and modify their surgical technique to improve patient outcome. It is also common for surgeons to analyze results before and after a change in technique to determine whether the change led to better results. Simple comparison of results before and after surgical modification may be confounded by the surgical learning curve. We developed a statistical method applicable to analyzing before/after surgical studies. We used simulation studies to compare different statistical analyses of before/after studies. We evaluated a simple 2-group comparison of results before and after the modification by the chi-square test and a novel bootstrap method that adjusts for the surgical learning curve. In the presence of the learning curve a simple 2-group comparison almost always showed an ineffective surgical modification to be of benefit. When the surgical modification was harmful, leading to a 10% decrease in the success rate, 2-group comparison nonetheless showed a statistically significant improvement in outcome about 80% of the time. The bootstrap method had only moderate power but did not show that ineffective surgical modifications were beneficial more than would be expected by chance. Simplistic approaches to the analysis of before/after surgical studies may lead to grossly erroneous results under the surgical learning curve. A straightforward alternative statistical method allows investigators to separate the effects of the learning curve from those of the surgical modification. Copyright (c) 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Optimizing anesthesia techniques in the ambulatory setting

    NARCIS (Netherlands)

    E. Galvin (Eilish)

    2007-01-01

    textabstractAmbulatory surgery refers to the process of admitting patients, administering anesthesia and surgical care, and discharging patients home following an appropriate level of recovery on the same day. The word ambulatory is derived from the latin word ambulare, which means ''to walk''. This

  20. Intraoperative technique as a factor in the prevention of surgical site infection.

    LENUS (Irish Health Repository)

    McHugh, S M

    2012-02-01

    Approximately five percent of patients who undergo surgery develop surgical site infections (SSIs) which are associated with an extra seven days as an inpatient and with increased postoperative mortality. The competence and technique of the surgeon is considered important in preventing SSI. We have reviewed the evidence on different aspects of surgical technique and its role in preventing SSI. The most recent guidelines from the National Institute for Health and Clinical Excellence in the UK recommend avoiding diathermy for skin incision even though this reduces incision time and blood loss, both associated with lower infection rates. Studies comparing different closure techniques, i.e. continuous versus interrupted sutures, have not found a statistically significant difference in the SSI rate, but using continuous sutures is quicker. For contaminated wounds, the surgical site should be left open for four days to allow for treatment of local infection before subsequent healing by primary intention. Surgical drains should be placed through separate incisions, closed suction drains are preferable to open drains, and all drains should be removed as soon as possible. There are relatively few large studies on the impact of surgical techniques on SSI rates. Larger multicentre prospective studies are required to define what aspects of surgical technique impact on SSI, to better inform surgical practice and support education programmes for surgical trainees.

  1. Intraoperative technique as a factor in the prevention of surgical site infection.

    LENUS (Irish Health Repository)

    McHugh, S M

    2011-02-28

    Approximately five percent of patients who undergo surgery develop surgical site infections (SSIs) which are associated with an extra seven days as an inpatient and with increased postoperative mortality. The competence and technique of the surgeon is considered important in preventing SSI. We have reviewed the evidence on different aspects of surgical technique and its role in preventing SSI. The most recent guidelines from the National Institute for Health and Clinical Excellence in the UK recommend avoiding diathermy for skin incision even though this reduces incision time and blood loss, both associated with lower infection rates. Studies comparing different closure techniques, i.e. continuous versus interrupted sutures, have not found a statistically significant difference in the SSI rate, but using continuous sutures is quicker. For contaminated wounds, the surgical site should be left open for four days to allow for treatment of local infection before subsequent healing by primary intention. Surgical drains should be placed through separate incisions, closed suction drains are preferable to open drains, and all drains should be removed as soon as possible. There are relatively few large studies on the impact of surgical techniques on SSI rates. Larger multicentre prospective studies are required to define what aspects of surgical technique impact on SSI, to better inform surgical practice and support education programmes for surgical trainees.

  2. Sacroiliac screw fixation: A mini review of surgical technique

    Directory of Open Access Journals (Sweden)

    Hernando Raphael Alvis-Miranda

    2014-01-01

    Full Text Available The sacral percutaneous fixation has many advantages but can be associated with a significant exposure to X-ray radiation. Currently, sacroiliac screw fixation represents the only minimally invasive technique to stabilize the posterior pelvic ring. It is a technique that should be used by experienced surgeons. We present a practical review of important aspects of this technique.

  3. Surgical strategies in patients with gallbladder cancer: nihilism to optimism.

    Science.gov (United States)

    Sikora, Sadiq S; Singh, Rajneesh K

    2006-06-15

    Gallbladder cancer is an aggressive disease with dismal results of surgical treatment and a poor prognosis. However, over the last few decades selected groups have reported improved results with aggressive surgery for gallbladder cancer. Review of recent world literature was done to provide an update on the current concepts of surgical treatment of this disease. Long-term survival is possible in early stage gallbladder carcinoma. Tis and T1a gallbladder carcinoma can be treated with simple cholecystectomy only. However, in T1b and beyond cancers, aggressive surgery (extended cholecystectomy) is important in improving the long-term prognosis. Laparoscopic cholecystectomy should not be performed where there is a high index of suspicion of malignancy due to the frequent association with factors (such as gallbladder perforation and bile spill) which may lead to implantation of cancer cells and dissemination. Surgical resection for advanced carcinoma gallbladder is recommended only if a potentially curative R0 resection is possible. Aggressive surgery with vascular and multivisceral resection has been shown to be feasible albeit with an increase in mortality and morbidity. However, the true benefit of these radical resections is yet to be realized, as the actual number of long-term survivors of advanced gallbladder carcinoma is few. Surgery for gallbladder carcinoma, like other malignancies, has the potential to be curative only in local or regional disease. Pattern of loco-regional spread of disease dictates the surgical procedure. Radical surgery improves survival in early gallbladder carcinoma. The long-term benefit of aggressive surgery for advanced disease is unclear and may be offset by the high mortality and morbidity. Copyright 2006 Wiley-Liss, Inc.

  4. Surgical attenuation of congenital portosystemic shunts in dogs. Techniques, complications and prognosis

    NARCIS (Netherlands)

    Kummeling, A.|info:eu-repo/dai/nl/304828793

    2009-01-01

    The general aim of this thesis was to identify factors associated with outcome after surgical attenuation of congenital portosystemic shunts (CPSS) in dogs and to clarify underlying mechanisms of postoperative recovery in this disease. Two surgical techniques used for CPSS attenuation, ligation and

  5. Evaluating the optimal timing of surgical antimicrobial prophylaxis: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Mujagic, Edin; Zwimpfer, Tibor; Marti, Walter R; Zwahlen, Marcel; Hoffmann, Henry; Kindler, Christoph; Fux, Christoph; Misteli, Heidi; Iselin, Lukas; Lugli, Andrea Kopp; Nebiker, Christian A; von Holzen, Urs; Vinzens, Fabrizio; von Strauss, Marco; Reck, Stefan; Kraljević, Marko; Widmer, Andreas F; Oertli, Daniel; Rosenthal, Rachel; Weber, Walter P

    2014-05-24

    Surgical site infections are the most common hospital-acquired infections among surgical patients. The administration of surgical antimicrobial prophylaxis reduces the risk of surgical site infections . The optimal timing of this procedure is still a matter of debate. While most studies suggest that it should be given as close to the incision time as possible, others conclude that this may be too late for optimal prevention of surgical site infections. A large observational study suggests that surgical antimicrobial prophylaxis should be administered 74 to 30 minutes before surgery. The aim of this article is to report the design and protocol of a randomized controlled trial investigating the optimal timing of surgical antimicrobial prophylaxis. In this bi-center randomized controlled trial conducted at two tertiary referral centers in Switzerland, we plan to include 5,000 patients undergoing general, oncologic, vascular and orthopedic trauma procedures. Patients are randomized in a 1:1 ratio into two groups: one receiving surgical antimicrobial prophylaxis in the anesthesia room (75 to 30 minutes before incision) and the other receiving surgical antimicrobial prophylaxis in the operating room (less than 30 minutes before incision). We expect a significantly lower rate of surgical site infections with surgical antimicrobial prophylaxis administered more than 30 minutes before the scheduled incision. The primary outcome is the occurrence of surgical site infections during a 30-day follow-up period (one year with an implant in place). When assuming a 5% surgical site infection risk with administration of surgical antimicrobial prophylaxis in the operating room, the planned sample size has an 80% power to detect a relative risk reduction for surgical site infections of 33% when administering surgical antimicrobial prophylaxis in the anesthesia room (with a two-sided type I error of 5%). We expect the study to be completed within three years. The results of this

  6. Surgical techniques to minimize shoulder pain after laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Donatsky, Anders Meller; Bjerrum, Flemming; Gögenür, Ismayil

    2013-01-01

    intraoperative surgical methods applied to minimize incidence or severity of SP after LC. Only papers published in English were included. Data extracted were year of publication, number of participants and allocation, nonsignificant or significant effect on incidence or severity of SP. RESULTS: A total of 31...... papers where included in the review. Seven, 8, and 12 papers investigated the effect of drains, abdominal wall lift (AWL), and low-pressure pneumoperitoneum respectively. Four papers investigated drain suction, active gas aspiration, low insufflation flow or N(2)O insufflation respectively...

  7. Generation of Articulated Mechanisms by Optimization Techniques

    DEFF Research Database (Denmark)

    Kawamoto, Atsushi

    2004-01-01

    optimization [Paper 2] 3. Branch and bound global optimization [Paper 3] 4. Path-generation problems [Paper 4] In terms of the objective of the articulated mechanism design problems, the first to third papers deal with maximization of output displacement, while the fourth paper solves prescribed path...... generation problems. From a mathematical programming point of view, the methods proposed in the first and third papers are categorized as deterministic global optimization, while those of the second and fourth papers are categorized as gradient-based local optimization. With respect to design variables, only...... directly affects the result of the associated sensitivity analysis. Another critical issue for mechanism design is the concept of mechanical degrees of freedom and this should be also considered for obtaining a proper articulated mechanism. The thesis treats this inherently discrete criterion in some...

  8. Surgical techniques for quantitative nutrient digestion and absorbtion studies in the pig

    DEFF Research Database (Denmark)

    Jørgensen, Henry; Serena, Anja; Theil, Peter Kappel

    2010-01-01

    Surgical techniques allow quantitative measurement of nutrient digestion and absorption in pigs. The present paper presents our updated techniques for anaesthesia and surgery. The surgery technique of catheterization of the portal vein, mesenteric vein and mesenteric artery, as well as the fitting...

  9. Safety and surgical techniques of C1 lateral mass screws

    International Nuclear Information System (INIS)

    Kubo, Shinichiro; Kuroki, Hiroshi; Hanado, Shoji; Hamanaka, Hideaki; Inomata, Naoki; Kuroki, Shuji; Chosa, Etsuo

    2010-01-01

    The objectives of this study were to evaluate the proper insertion techniques of C1 lateral mass screws. Eighteen consecutive patients were examined after upper cervical fusion using twenty-nine C1 lateral mass screws. Screws were placed by three different techniques; Goel's technique (4), Tan's technique (20), Notching technique (5). Pre and post-operative CT scans with multiplanar reconstruction were used to detect cortical breaches and direction of screws. No transverse foramen and vertebral groove violation was found in CT scans. Three had breached superior articular facet of the atlas. However, the range of motion (R.O.M) of atlanto-occipital joints had not changed postoperatively. Theses screws were inserted with Tan's technique and two of three were directed medially. It is feasible to safely insert C1 lateral mass screws when correct insertion point and direction are considered preoperatively. However, care should be taken because screws can violate the atlanto-occipital joint especially with Tan's technique. (author)

  10. Optimal placement of FACTS devices using optimization techniques: A review

    Science.gov (United States)

    Gaur, Dipesh; Mathew, Lini

    2018-03-01

    Modern power system is dealt with overloading problem especially transmission network which works on their maximum limit. Today’s power system network tends to become unstable and prone to collapse due to disturbances. Flexible AC Transmission system (FACTS) provides solution to problems like line overloading, voltage stability, losses, power flow etc. FACTS can play important role in improving static and dynamic performance of power system. FACTS devices need high initial investment. Therefore, FACTS location, type and their rating are vital and should be optimized to place in the network for maximum benefit. In this paper, different optimization methods like Particle Swarm Optimization (PSO), Genetic Algorithm (GA) etc. are discussed and compared for optimal location, type and rating of devices. FACTS devices such as Thyristor Controlled Series Compensator (TCSC), Static Var Compensator (SVC) and Static Synchronous Compensator (STATCOM) are considered here. Mentioned FACTS controllers effects on different IEEE bus network parameters like generation cost, active power loss, voltage stability etc. have been analyzed and compared among the devices.

  11. Application of minimally invasive technique in surgical treatment of pancreatic diseases

    Directory of Open Access Journals (Sweden)

    ZHANG Yixi

    2015-05-01

    Full Text Available In recent years, with the rapid development of minimally invasive concept, from laparoscopic operation to three-dimension laparoscopic technique and to robotic surgical system, treatment modalities have changed a lot. Pancreatic diseases, including multiple lesions, have different prognoses. An appropriate surgical procedure should be selected while ensuring the radical treatment of disease, so as to minimize the injury to patients and the impairment of organ function. Minimally invasive technique is of great significance in the surgical treatment of pancreatic diseases.

  12. Optimal Technique in Cardiac Anesthesia Recovery

    NARCIS (Netherlands)

    Svircevic, V.

    2014-01-01

    The aim of this thesis is to evaluate fast-track cardiac anesthesia techniques and investigate their impact on postoperative mortality, morbidity and quality of life. The following topics will be discussed in the thesis. (1.) Is fast track cardiac anesthesia a safe technique for cardiac surgery?

  13. 9th International Conference on Optimization : Techniques and Applications

    CERN Document Server

    Wang, Song; Wu, Soon-Yi

    2015-01-01

    This book presents the latest research findings and state-of-the-art solutions on optimization techniques and provides new research direction and developments. Both the theoretical and practical aspects of the book will be much beneficial to experts and students in optimization and operation research community. It selects high quality papers from The International Conference on Optimization: Techniques and Applications (ICOTA2013). The conference is an official conference series of POP (The Pacific Optimization Research Activity Group; there are over 500 active members). These state-of-the-art works in this book authored by recognized experts will make contributions to the development of optimization with its applications.

  14. PREFERED SURGICAL TECHNIQUE USED BY ORTHOPEDISTS IN ACUTE ACROMIOCLAVICULAR DISLOCATION

    Science.gov (United States)

    NISHIMI, ALEXANDRE YUKIO; ARBEX, DEMETRIO SIMÃO; MARTINS, DIOGO LUCAS CAMPOS; GUSMÃO, CARLOS VINICIUS BUARQUE DE; BONGIOVANNI, ROBERTO RANGEL; PASCARELLI, LUCIANO

    2016-01-01

    ABSTRACT Objective: To determine whether training on shoulder and elbow surgery influences the orthopedist surgeons' preferred technique to address acute acromioclavicular joint dislocation (ACD). Methods: A survey was conducted with shoulder and elbow specialists and general orthopedists on their preferred technique to address acute ACD. Results: Thirty specialists and forty-five general orthopedists joined the study. Most specialists preferred the endobutton technique, while most general orthopedists preferred the modified Phemister procedure for coracoclavicular ligament repair using anchors. We found no difference between specialists and general orthopedists in the number of tunnels used to repair the coracoclavicular ligament; preferred method for wire insertion through the clavicular tunnels; buried versus unburied Kirschner wire insertion for acromioclavicular temporary fixation; and time for its removal; and regarding the suture thread used for deltotrapezoidal fascia closure. Conclusion: Training on shoulder and elbow surgery influences the surgeons' preferred technique to address acute ACD. Level of Evidence V, Expert Opinion. PMID:28149190

  15. Optimal management of Barrett's esophagus: pharmacologic, endoscopic, and surgical interventions

    Directory of Open Access Journals (Sweden)

    Konda VJA

    2011-11-01

    Full Text Available Vani JA Konda1, Kunal Dalal21Section of Gastroenterology, Department of Medicine, 2Department of Internal Medicine, University of Chicago Medical Center, Chicago, Illinois, USAAbstract: Esophageal adenocarcinoma and its precursor, Barrett's esophagus, are rapidly rising in incidence. This review serves to highlight the role of pharmacologic, endoscopic, and surgical intervention in the management of Barrett's esophagus, which requires acid suppression and endoscopic assessment. Treatment with a proton pump inhibitor may decrease acid exposure and delay the progression to dysplasia. Patients who require aspirin for cardioprotection or other indications may also benefit in terms of a protective effect against the development of esophageal cancer. However, without other indications, aspirin is not indicated solely to prevent cancer. A careful endoscopic examination should include assessment of any visible lesions in a Barrett's segment. An expert gastrointestinal pathologist should confirm neoplasia in the setting of Barrett's esophagus. For those patients with high-grade dysplasia or intramucosal carcinoma, careful consideration of endoscopic therapy or surgical therapy must be given. All visible lesions in the setting of dysplasia should be targeted with focal endoscopic mucosal resection for both accurate histopathologic diagnosis and treatment. The remainder of the Barrett's epithelium should be eradicated to address all synchronous and metachronous lesions. This may be done by tissue acquiring or nontissue acquiring means. Radiofrequency ablation has a positive benefit-risk profile for flat Barrett's esophagus. At this time, endoscopic therapy is not indicated for nondysplastic Barrett's esophagus. Esophagectomy is still reserved for selected cases with evidence of lymph node metastasis, unsuccessful endoscopic therapy, or with high-risk features of high-grade dysplasia or intramucosal carcinoma.Keywords: Barrett's esophagus, high

  16. Hybrid Techniques for Optimizing Complex Systems

    Science.gov (United States)

    2009-12-01

    relay placement problem, we modeled the network as a mechanical system with springs and a viscous damper ⎯a widely used approach for solving optimization...fundamental mathematical tools in many branches of physics such as fluid and solid mechanics, and general relativity [108]. More recently, several

  17. A standardized surgical technique for rat superior cervical ganglionectomy

    DEFF Research Database (Denmark)

    Savastano, Luis Emilio; Castro, Analía Elizabeth; Fitt, Marcos René

    2010-01-01

    Superior cervical ganglionectomy (SCGx) is a valuable microsurgical model to study the role of the sympathetic nervous system in a vast array of physiological and pathological processes, including homeostatic regulation, circadian biology and the dynamics of neuronal dysfunction and recovery afte...... expect that the following standardized and optimized protocol will allow researchers to organize knowledge into a cohesive framework in those areas where the SCGx is applied....

  18. Evolutionary optimization technique for site layout planning

    KAUST Repository

    El Ansary, Ayman M.; Shalaby, Mohamed

    2014-01-01

    of design requirements. The developed technique is based on genetic algorithm which explores the search space for possible solutions. This study considers two dimensional site planning problems. However, it can be extended to solve three dimensional cases. A

  19. Optimal Technique in Cardiac Anesthesia Recovery

    OpenAIRE

    Svircevic, V.

    2014-01-01

    The aim of this thesis is to evaluate fast-track cardiac anesthesia techniques and investigate their impact on postoperative mortality, morbidity and quality of life. The following topics will be discussed in the thesis. (1.) Is fast track cardiac anesthesia a safe technique for cardiac surgery? (2.) Does thoracic epidural anesthesia have an effect on mortality and morbidity after cardiac surgery? (3.) Does thoracic epidural anesthesia have an effect on quality of life after cardiac surgery? ...

  20. Vaginal-sparing ventral buccal mucosal graft urethroplasty for female urethral stricture: A novel modification of surgical technique.

    Science.gov (United States)

    Hoag, Nathan; Gani, Johan; Chee, Justin

    2016-07-01

    To present a novel modification of surgical technique to treat female urethral stricture (FUS) by a vaginal-sparing ventral buccal mucosal urethroplasty. Recurrent FUS represents an uncommon, though difficult clinical scenario to manage definitively. A variety of surgical techniques have been described to date, yet a lack of consensus on the optimal procedure persists. We present a 51-year-old female with urethral stricture involving the entire urethra. Suspected etiology was iatrogenic from cystoscopy 17 years prior. Since then, the patient had undergone at least 25 formal urethral dilations and periods of self-dilation. In lithotomy position, the urethra was dilated to accommodate forceps, and ventral urethrotomy carried out sharply, exposing a bed of periurethral tissue. Buccal mucosa was harvested, and a ventral inlay technique facilitated by a nasal speculum, was used to place the graft from the proximal urethra/bladder neck to urethral meatus without a vaginal incision. Graft was sutured into place, and urethral Foley catheter inserted. The vaginal-sparing ventral buccal mucosal graft urethroplasty was deemed successful as of last follow-up. Flexible cystoscopy demonstrated patency of the repair at 6 months. At 10 months of follow-up, the patient was voiding well, with no urinary incontinence. No further interventions have been required. This case describes a novel modification of surgical technique for performing buccal mucosal urethroplasty for FUS. By avoiding incision of the vaginal mucosa, benefits may include reduced: morbidity, urinary incontinence, and wound complications including urethro-vaginal fistula.

  1. Comparison of two surgical techniques in large incisional hernias

    Directory of Open Access Journals (Sweden)

    Mustafa Sit

    2014-03-01

    Full Text Available Objectives: Incisional hernias occur from incisions of previous abdominal operations. It is an often complication of abdominal interventions. Prevalence of incisional hernias is approximately 2.9% and 3.6% in vertical midline incisions and transverse incisions, respectively. Incisional hernias cause morbidity and loss of manpower. The only treatment option is surgery. We aimed to compare surgical methods of incisional hernias and discuss the postoperative data in this retrospective report. Methods: We retrospectively analyzed the data of 54 patients with large incisional hernias operated between 2007 and 2011. Results: We compared age, chronic diseases (e.g. Chronic obstructive pulmonary disease, diabetes mellitus,which may cause postoperative recurrence, gender, personal factors, such as patients undergoing incisional hernia repair mesh over solid fascia less or over than 5 cm with the placement of decolation; recurrence, the development of postoperative seroma, receiving postoperative drainage and postoperative length of hospital stay were compared. While the recurrence rate of less than 5 cm above the decolation; seroma development, no significant difference in length of hospital stay and drain times to get. Conclusion: In conclusion, we think that recurrence rate should be reduced by dissection of 5 cm intact fascia and grafting in incisional hernias of anterior abdominal wall. J Clin Exp Invest 2014; 5 (1: 36-39

  2. Assessing suturing techniques using a virtual reality surgical simulator.

    Science.gov (United States)

    Kazemi, Hamed; Rappel, James K; Poston, Timothy; Hai Lim, Beng; Burdet, Etienne; Leong Teo, Chee

    2010-09-01

    Advantages of virtual-reality simulators surgical skill assessment and training include more training time, no risk to patient, repeatable difficulty level, reliable feedback, without the resource demands, and ethical issues of animal-based training. We tested this for a key subtask and showed a strong link between skill in the simulator and in reality. Suturing performance was assessed for four groups of participants, including experienced surgeons and naive subjects, on a custom-made virtual-reality simulator. Each subject tried the experiment 30 times using five different types of needles to perform a standardized suture placement task. Traditional metrics of performance as well as new metrics enabled by our system were proposed, and the data indicate difference between trained and untrained performance. In all traditional parameters such as time, number of attempts, and motion quantity, the medical surgeons outperformed the other three groups, though differences were not significant. However, motion smoothness, penetration and exit angles, tear size areas, and orientation change were statistically significant in the trained group when compared with untrained group. This suggests that these parameters can be used in virtual microsurgery training.

  3. What matters after sleeve gastrectomy: patient characteristics or surgical technique?

    Science.gov (United States)

    Dhar, Vikrom K; Hanseman, Dennis J; Watkins, Brad M; Paquette, Ian M; Shah, Shimul A; Thompson, Jonathan R

    2018-03-01

    The impact of operative technique on outcomes in laparoscopic sleeve gastrectomy has been explored previously; however, the relative importance of patient characteristics remains unknown. Our aim was to characterize national variability in operative technique for laparoscopic sleeve gastrectomy and determine whether patient-specific factors are more critical to predicting outcomes. We queried the database of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program for laparoscopic sleeve gastrostomies performed in 2015 (n = 88,845). Logistic regression models were used to determine predictors of postoperative outcomes. In 2015, >460 variations of laparoscopic sleeve gastrectomy were performed based on combinations of bougie size, distance from the pylorus, use of staple line reinforcement, and oversewing of the staple line. Despite such substantial variability, technique variants were not predictive of outcomes, including perioperative morbidity, leak, or bleeding (all P ≥ .05). Instead, preoperative patient characteristics were found to be more predictive of these outcomes after laparoscopic sleeve gastrectomy. Only history of gastroesophageal disease (odds ratio 1.44, 95% confidence interval 1.08-1.91, P < .01) was associated with leak. Considerable variability exists in technique among surgeons nationally, but patient characteristics are more predictive of adverse outcomes after laparoscopic sleeve gastrectomy. Bundled payments and reimbursement policies should account for patient-specific factors in addition to current accreditation and volume thresholds when deciding risk-adjustment strategies. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Surgical Anatomy and Microvascular Surgical Technique Relevant to Experimental Renal Transplant in Rat Employing Aortic and Inferior Venacaval Conduits.

    Science.gov (United States)

    Shrestha, Badri Man; Haylor, John

    2017-11-15

    Rat models of renal transplant are used to investigate immunologic processes and responses to therapeutic agents before their translation into routine clinical practice. In this study, we have described details of rat surgical anatomy and our experiences with the microvascular surgical technique relevant to renal transplant by employing donor inferior vena cava and aortic conduits. For this study, 175 rats (151 Lewis and 24 Fisher) were used to establish the Fisher-Lewis rat model of chronic allograft injury at our institution. Anatomic and technical details were recorded during the period of training and establishment of the model. A final group of 12 transplanted rats were studied for an average duration of 51 weeks for the Lewis-to-Lewis isografts (5 rats) and 42 weeks for the Fisher-to-Lewis allografts (7 rats). Functional measurements and histology confirmed the diagnosis of chronic allograft injury. Mastering the anatomic details and microvascular surgical techniques can lead to the successful establishment of an experimental renal transplant model.

  5. Numerical optimization of alignment reproducibility for customizable surgical guides

    NARCIS (Netherlands)

    Kroes, T.; Valstar, E.R.; Eisemann, E.

    2015-01-01

    Purpose Computer-assisted orthopedic surgery aims at minimizing invasiveness, postoperative pain, and morbidity with computer-assisted preoperative planning and intra-operative guidance techniques, of which camera-based navigation and patient-specific templates (PST) are the most common. PSTs are

  6. A novel technique for active vibration control, based on optimal

    Indian Academy of Sciences (India)

    In the last few decades, researchers have proposed many control techniques to suppress unwanted vibrations in a structure. In this work, a novel and simple technique is proposed for the active vibration control. In this technique, an optimal tracking control is employed to suppress vibrations in a structure by simultaneously ...

  7. Complex energy system management using optimization techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bridgeman, Stuart; Hurdowar-Castro, Diana; Allen, Rick; Olason, Tryggvi; Welt, Francois

    2010-09-15

    Modern energy systems are often very complex with respect to the mix of generation sources, energy storage, transmission, and avenues to market. Historically, power was provided by government organizations to load centers, and pricing was provided in a regulatory manner. In recent years, this process has been displaced by the independent system operator (ISO). This complexity makes the operation of these systems very difficult, since the components of the system are interdependent. Consequently, computer-based large-scale simulation and optimization methods like Decision Support Systems are now being used. This paper discusses the application of a DSS to operations and planning systems.

  8. A modified surgical technique for reconstruction of an acute acromioclavicular joint dislocation

    Science.gov (United States)

    Marchie, Anthony; Kumar, Arun; Catre, Melanio

    2009-01-01

    We report a modified surgical technique for reconstruction of coracoclavicular and acromioclavicular ligaments after acute dislocation of acromioclavicular joint using suture anchors. We have repaired 3 consecutive type III acromioclavicular dislocations with good results. This technique is simple and safe and allows anatomical reconstruction of the ligaments in acute dislocations. PMID:20671868

  9. A modified surgical technique for reconstruction of an acute acromioclavicular joint dislocation

    OpenAIRE

    Marchie, Anthony; Kumar, Arun; Catre, Melanio

    2009-01-01

    We report a modified surgical technique for reconstruction of coracoclavicular and acromioclavicular ligaments after acute dislocation of acromioclavicular joint using suture anchors. We have repaired 3 consecutive type III acromioclavicular dislocations with good results. This technique is simple and safe and allows anatomical reconstruction of the ligaments in acute dislocations.

  10. Optimal surgical approach for the treatment of Quervains disease: A surgical-anatomical study

    NARCIS (Netherlands)

    A.R. Poublon (Alex); G.J. Kleinrensink (Gert Jan); A.L.A. Kerver (Anton); J.H. Coert (Henk); E.T. Walbeehm (Erik)

    2018-01-01

    textabstractAIM To determine which of the common used incision techniques has the lowest chance of iatrogenic damage to the nerves which at risk are the superficial branch of the radial nerve (SBRN) and the Lateral Antebrachial Cutaneous Nerve (LABCN). METHODS Twenty embalmed arms were dissected and

  11. Minimally Invasive Surgical Approach to Distal Fibula Fractures: A Technique Tip

    Directory of Open Access Journals (Sweden)

    Tyler A. Gonzalez

    2017-01-01

    Full Text Available Wound complications following ankle fracture surgery are a major concern. Through the use of minimally invasive surgical techniques some of these complications can be mitigated. Recent investigations have reported on percutaneous fixation of distal fibula fractures demonstrating similar radiographic and functional outcomes to traditional open approaches. The purpose of this manuscript is to describe in detail the minimally invasive surgical approach for distal fibula fractures.

  12. Mesial temporal lobe epilepsy - An overview of surgical techniques.

    Science.gov (United States)

    Muzumdar, Dattatraya; Patil, Manoj; Goel, Atul; Ravat, Sangeeta; Sawant, Nina; Shah, Urvashi

    2016-12-01

    Mesial temporal lobe epilepsy is one of the commonest indications for epilepsy surgery. Presurgical evaluation for drug resistant epilepsy and identification of appropriate candidates for surgery is essential for optimal seizure freedom. The anatomy of mesial temporal lobe is complex and needs to be understood in the context of the advanced imaging, ictal and interictal Video_EEG monitoring, neuropsychology and psychiatric considerations. The completeness of disconnection of epileptogenic neural networks is paramount and is correlated with the extent of resection of the mesial temporal structures. In the Indian subcontinent, a standard but extended anterior temporal lobectomy is a viable option in view of the diverse socioeconomic, cultural and pathological considerations. The maximum utilization of epilepsy surgery services in this region is also a challenge. There is a need for regional comprehensive epilepsy care teams in a tertiary care academic hospital to form centers of excellence catering to a large population. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  13. Bayer Digester Optimization Studies using Computer Techniques

    Science.gov (United States)

    Kotte, Jan J.; Schleider, Victor H.

    Theoretically required heat transfer performance by the multistaged flash heat reclaim system of a high pressure Bayer digester unit is determined for various conditions of discharge temperature, excess flash vapor and indirect steam addition. Solution of simultaneous heat balances around the digester vessels and the heat reclaim system yields the magnitude of available heat for representation of each case on a temperature-enthalpy diagram, where graphical fit of the number of flash stages fixes the heater requirements. Both the heat balances and the trial-and-error graphical solution are adapted to solution by digital computer techniques.

  14. Optimal design of a novel remote center-of-motion mechanism for minimally invasive surgical robot

    Science.gov (United States)

    Sun, Jingyuan; Yan, Zhiyuan; Du, Zhijiang

    2017-06-01

    Surgical robot with a remote center-of-motion (RCM) plays an important role in minimally invasive surgery (MIS) field. To make the mechanism has high flexibility and meet the demand of movements during processing of operation, an optimized RCM mechanism is proposed in this paper. Then, the kinematic performance and workspace are analyzed. Finally, a new optimization objective function is built by using the condition number index and the workspace index.

  15. Diagnosis of scaphoid fracture: optimal imaging techniques

    Directory of Open Access Journals (Sweden)

    Geijer M

    2013-07-01

    Full Text Available Mats Geijer Center for Medical Imaging and Physiology, Skåne University Hospital and Lund University, Lund, Sweden Abstract: This review aims to provide an overview of modern imaging techniques for evaluation of scaphoid fracture, with emphasis on occult fractures and an outlook on the possible evolution of imaging; it also gives an overview of the pathologic and anatomic basis for selection of techniques. Displaced scaphoid fractures detected by wrist radiography, with or without special scaphoid views, pose no diagnostic problems. After wrist trauma with clinically suspected scaphoid fracture and normal scaphoid radiography, most patients will have no clinically important fracture. Between 5% and 19% of patients (on average 16% in meta-analyses will, however, have an occult scaphoid fracture which, untreated, may lead to later, potentially devastating, complications. Follow-up imaging may be done with repeat radiography, tomosynthesis, computed tomography, magnetic resonance imaging (MRI, or bone scintigraphy. However, no method is perfect, and choice of imaging may be based on availability, cost, perceived accuracy, or personal preference. Generally, MRI and bone scintigraphy are regarded as the most sensitive modalities, but both are flawed by false positive results at various rates. Keywords: occult fracture, wrist, radiography, computed tomography, magnetic resonance imaging, radionuclide imaging

  16. Pectus bar removal: surgical technique and strategy to avoid complications.

    Science.gov (United States)

    Park, Hyung Joo; Kim, Kyung Soo

    2016-01-01

    Pectus bar removal is the final stage of the procedure for minimally invasive repair of pectus excavatum. Based on our experience with one of the largest scale data, we would like to address the important issues in pectus bar removal, such as appropriate duration of bar maintenance, techniques for bar removal, and strategies to avoid complications. Between September 1999 and August 2015, we operated on 2,553 patients with pectus excavatum and carinatum using pectus bars for a minimally invasive approach. Among them, 1,821 patients (71.3%) underwent pectus bar removal as a final stage of pectus deformity repair, and their data were analyzed retrospectively to identify the outcomes and adverse effects of the pectus bar removal procedure. The mean age of the patients was 9.13 years (range, 16 months to 44 years) and the male to female ratio was 3.55. The study is approved by the Institutional Review Board (IRB), the ethical committee of Seoul St. Mary's Hospital. The IRB has exempted the informed consent from every patient in this study due to this is a retrospective chart review without revealing any patients' personal data. Our technique involved straightening of the bar in a supine position. The overall mean duration of pectus bar maintenance was 2.57 years (range, 4 months to 14 years). The mean duration was 2.02 years (range, 4 months to 7 years) for children under 12 years, 2.99 years (range, 7 months to 9 years) for teenagers aged 12-20 years, and 3.53 years (range, 3 months to 14 years) for adults over 20 years. Forty-eight patients (2.6%) underwent bar removal more than 5 years after bar insertion and 58 patients (3.2%) underwent bar removal earlier than initially planned. The most common adverse reaction after bar removal was wound seroma including infection (43 patients, 2.36%). Recurrence after bar removal occurred in nine patients (0.49%), and seven of these required redo repair (0.38%). Pectus bar removal is a safe and straightforward procedure with a

  17. Acceleration techniques in the univariate Lipschitz global optimization

    Science.gov (United States)

    Sergeyev, Yaroslav D.; Kvasov, Dmitri E.; Mukhametzhanov, Marat S.; De Franco, Angela

    2016-10-01

    Univariate box-constrained Lipschitz global optimization problems are considered in this contribution. Geometric and information statistical approaches are presented. The novel powerful local tuning and local improvement techniques are described in the contribution as well as the traditional ways to estimate the Lipschitz constant. The advantages of the presented local tuning and local improvement techniques are demonstrated using the operational characteristics approach for comparing deterministic global optimization algorithms on the class of 100 widely used test functions.

  18. Radical prostatectomy: evolution of surgical technique from the laparoscopic point of view

    Directory of Open Access Journals (Sweden)

    Xavier Cathelineau

    2010-04-01

    Full Text Available PURPOSE: To review the literature and present a current picture of the evolution in radical prostatectomy from the laparoscopic point of view. MATERIALS AND METHODS: We conducted an extensive Medline literature search. Articles obtained regarding laparoscopic radical prostatectomy (LRP and our experience at Institut Montsouris were used for reassessing anatomical and technical issues in radical prostatectomy. RESULTS: LRP nuances were reassessed by surgical teams in order to verify possible weaknesses in their performance. Our basic approach was to carefully study the anatomy and pioneer open surgery descriptions in order to standardized and master a technique. The learning curve is presented in terms of an objective evaluation of outcomes for cancer control and functional results. In terms of technique-outcomes, there are several key elements in radical prostatectomy, such as dorsal vein control-apex exposure and nerve sparing with particular implications in oncological and functional results. Major variations among the surgical teams' performance and follow-up prevented objective comparisons in radical prostatectomy. The remarkable evolution of LRP needs to be supported by comprehensive results. CONCLUSIONS: Radical prostatectomy is a complex surgical operation with difficult objectives. Surgical technique should be standardized in order to allow an adequate and reliable performance in all settings, keeping in mind that cancer control remains the primary objective. Reassessing anatomy and a return to basics in surgical technique is the means to improve outcomes and overcome the difficult task of the learning curve, especially in minimally access urological surgery.

  19. An innovative surgical technique for treating penile incarceration injury caused by heavy metallic ring

    Directory of Open Access Journals (Sweden)

    S J Baruah

    2009-01-01

    Full Text Available Penile incarceration injury by heavy metallic ring is a rare genital injury. A man may place metal object for erotic or autoerotic purposes, for masturbation or increasing erection, and due to psychiatric disturbances are some of the reasons for a penile incarceration injury. The incarcerating injury results in reduced blood flow distal to the injury, leading to edema, ischemia, and sometimes gangrene. These injuries are divided into five grades and their treatment options are divided into four groups. Surgical techniques are reserved for the advanced grades (Grades IV and V. We describe an innovative surgical technique, which can be adopted in Grades II and III injuries.

  20. Evaluation of primary and secondary stability of titanium implants using different surgical techniques.

    Science.gov (United States)

    Tabassum, Afsheen; Meijer, Gert J; Walboomers, X Frank; Jansen, John A

    2014-04-01

    To investigate the influence of different surgical techniques on the primary and secondary implant stability using trabecular bone of goats as an implantation model. In the iliac crest of eight goats, 48 cylindrical-screw-type implants with a diameter of 4.2 mm (Dyna(®) ; Bergen op Zoom, the Netherlands) were installed, using three different surgical techniques: (i) 5% undersized, using a final drill diameter of 4 mm; (ii) 15% undersized, using a final drill diameter of 3.6 mm; and (iii) 25% undersized, using a final drill diameter of 3.2 mm. Peak insertion torque values were measured by a Digital(®) (MARK-10 Corporation, New York, NY, USA) torque gauge instrument during placement. At 3 weeks after implantation, removal torque was measured. Histomorphometrically, the peri-implant bone volume was measured in three zones; the inner zone (0-500 μm), the middle zone (500-1000 μm) and the outer zone (1000-1500 μm). Evaluation of the obtained data demonstrated no statistically significant difference between different surgical techniques regarding removal torque values. With respect to the percentage peri-implant bone volume (%BV), also no significant difference could be observed between all three applied surgical techniques for both the inner, middle and outer zone. However, irrespective of the surgical technique, it was noticed that the %BV was significantly higher for the inner zone as compared to middle and outer zone (P < 0.05) around the implant. At 3 weeks after implant installation, independent of the used undersized surgical technique, the %BV in the inner zone (0-500 μm) peri-implant area was improved due to both condensation of the surrounding bone as also the translocation of host bone particles along the implant surface. Surprisingly, no mechanical beneficial effect of the 25% undersized surgical technique could be observed as compared to the 5% or 15% undersized surgical technique to improve primary or secondary implant stability. © 2013

  1. Surgical robotics beyond enhanced dexterity instrumentation: a survey of machine learning techniques and their role in intelligent and autonomous surgical actions.

    Science.gov (United States)

    Kassahun, Yohannes; Yu, Bingbin; Tibebu, Abraham Temesgen; Stoyanov, Danail; Giannarou, Stamatia; Metzen, Jan Hendrik; Vander Poorten, Emmanuel

    2016-04-01

    Advances in technology and computing play an increasingly important role in the evolution of modern surgical techniques and paradigms. This article reviews the current role of machine learning (ML) techniques in the context of surgery with a focus on surgical robotics (SR). Also, we provide a perspective on the future possibilities for enhancing the effectiveness of procedures by integrating ML in the operating room. The review is focused on ML techniques directly applied to surgery, surgical robotics, surgical training and assessment. The widespread use of ML methods in diagnosis and medical image computing is beyond the scope of the review. Searches were performed on PubMed and IEEE Explore using combinations of keywords: ML, surgery, robotics, surgical and medical robotics, skill learning, skill analysis and learning to perceive. Studies making use of ML methods in the context of surgery are increasingly being reported. In particular, there is an increasing interest in using ML for developing tools to understand and model surgical skill and competence or to extract surgical workflow. Many researchers begin to integrate this understanding into the control of recent surgical robots and devices. ML is an expanding field. It is popular as it allows efficient processing of vast amounts of data for interpreting and real-time decision making. Already widely used in imaging and diagnosis, it is believed that ML will also play an important role in surgery and interventional treatments. In particular, ML could become a game changer into the conception of cognitive surgical robots. Such robots endowed with cognitive skills would assist the surgical team also on a cognitive level, such as possibly lowering the mental load of the team. For example, ML could help extracting surgical skill, learned through demonstration by human experts, and could transfer this to robotic skills. Such intelligent surgical assistance would significantly surpass the state of the art in surgical

  2. Tabu search, a versatile technique for the functions optimization

    International Nuclear Information System (INIS)

    Castillo M, J.A.

    2003-01-01

    The basic elements of the Tabu search technique are presented, putting emphasis in the qualities that it has in comparison with the traditional methods of optimization known as in descending pass. Later on some modifications are sketched that have been implemented in the technique along the time, so that this it is but robust. Finally they are given to know some areas where this technique has been applied, obtaining successful results. (Author)

  3. Hereditary spherocytosis and partial splenectomy in children: review of surgical technique and the role of imaging

    International Nuclear Information System (INIS)

    Hollingsworth, Caroline L.; Rice, Henry E.

    2010-01-01

    The risks associated with total splenectomy, including overwhelming postsplenectomy infection, have led to an interest in the use of partial splenectomy as an alternative surgical option for children with congenital hemolytic anemias and hypersplenism. Partial splenectomy, a procedure designed to remove enough spleen to improve anemia and avoid complications of splenic sequestration while preserving splenic function, has shown promise in children. Radiologic imaging is essential for the preoperative evaluation and postoperative care for children undergoing partial splenectomy and offers a broad range of critical clinical information essential for care of these complex children. It is imperative for radiologists involved in the care of these children to be familiar with the surgical technique and imaging options for these procedures. This article reviews the surgical technique as well as the current status of various diagnostic imaging options used for children undergoing partial splenectomy, highlighting technical aspects and specific clinical information obtained by each modality. (orig.)

  4. Hereditary spherocytosis and partial splenectomy in children: review of surgical technique and the role of imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hollingsworth, Caroline L. [Duke University Medical Center, Department of Radiology, Box 3808, Durham, NC (United States); Rice, Henry E. [Duke University Medical Center, Department of Surgery, Durham, NC (United States)

    2010-07-15

    The risks associated with total splenectomy, including overwhelming postsplenectomy infection, have led to an interest in the use of partial splenectomy as an alternative surgical option for children with congenital hemolytic anemias and hypersplenism. Partial splenectomy, a procedure designed to remove enough spleen to improve anemia and avoid complications of splenic sequestration while preserving splenic function, has shown promise in children. Radiologic imaging is essential for the preoperative evaluation and postoperative care for children undergoing partial splenectomy and offers a broad range of critical clinical information essential for care of these complex children. It is imperative for radiologists involved in the care of these children to be familiar with the surgical technique and imaging options for these procedures. This article reviews the surgical technique as well as the current status of various diagnostic imaging options used for children undergoing partial splenectomy, highlighting technical aspects and specific clinical information obtained by each modality. (orig.)

  5. SURGICAL TECHNIQUE

    African Journals Online (AJOL)

    We describe a simple form of posterior spinal surgery for patients with tuberculous ... malnutrition and other concomitant diseases tuberculosis (T B) of ... Positioning: We use the prone position with hip and .... can fracture, get absorbed or slip.

  6. Triple-Tube-Ostomy: A Novel Technique for the Surgical Treatment of Iatrogenic Duodenal Perforation

    Directory of Open Access Journals (Sweden)

    Nobuaki Fujikuni

    2011-12-01

    Full Text Available Although duodenal perforation is currently an infrequent complication of medical procedures, its incidence in the future predictably will increase as endoscopic treatment of duodenal neoplasms becomes more frequently used. In some cases, duodenal perforation is difficult to treat even surgically. We report here a novel technique called ‘triple-tube-ostomy’ for the treatment of iatrogenic duodenal perforation. Since November 2009, there have been three cases of iatrogenic perforation of the duodenum, due to various causes, which we have treated with our novel technique. The main principles of the technique are biliary diversion, decompression of the duodenum, and early enteral nutrition. All patients who underwent the triple-tube-ostomy procedure had good postoperative courses, with few complications. The novel surgical technique we describe in this report is safe, reliable, easy to learn and perform, and led to a good postoperative course in all cases where we performed it.

  7. Posterior Segment Intraocular Foreign Body: Extraction Surgical Techniques, Timing, and Indications for Vitrectomy

    Directory of Open Access Journals (Sweden)

    Dante A. Guevara-Villarreal

    2016-01-01

    Full Text Available Ocular penetrating injury with Intraocular Foreign Body (IOFB is a common form of ocular injury. Several techniques to remove IOFB have been reported by different authors. The aim of this publication is to review different timing and surgical techniques related to the extraction of IOFB. Material and Methods. A PubMed search on “Extraction of Intraocular Foreign Body,” “Timing for Surgery Intraocular Foreign Body,” and “Surgical Technique Intraocular Foreign Body” was made. Results. Potential advantages of immediate and delayed IOFB removal have been reported with different results. Several techniques to remove IOFB have been reported by different authors with good results. Conclusion. The most important factor at the time to perform IOFB extraction is the experience of the surgeon.

  8. Comparative study of 2 surgical techniques for castration of guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Guilmette, Josée; Langlois, Isabelle; Hélie, Pierre; El Warrak, Alexander de Oliveira

    2015-10-01

    The objective of this study was to compare 2 surgical approaches (scrotal or abdominal) for castration of guinea pigs and to investigate post-operative infection rates with either technique. Forty-eight guinea pigs were castrated by scrotal or abdominal technique after being randomly assigned to 1 of 2 groups (n = 24). Individuals were either castrated by an experienced exotic animal surgeon (n = 12) or by an experienced small animal surgeon (n = 12). Surgical wounds were evaluated daily before euthanasia for histological evaluation 2 wks after surgery. Post-operative infection rate was significantly higher in the scrotal group than in the abdominal group, with a higher rate for the experienced small animal surgeon. Castration of guinea pigs with the abdominal technique is significantly faster and has a significantly lower post-operative infection rate than the scrotal technique.

  9. The Suprameatal Approach: A Safe Alternative Surgical Technique for Cochlear Implantation

    NARCIS (Netherlands)

    Postelmans, Job T. F.; Tange, Rinze A.; Stokroos, Robert J.; Grolman, Wilko

    2010-01-01

    Objective: To report on surgical complications arising post-operatively in 104 patients undergoing cochlear implantation surgery using the suprameatal approach (SMA). Second, to examine the advantages and disadvantages of the SMA technique compared with the classic mastoidectomy using the posterior

  10. A method of handing down surgical clipping technique for cerebral aneurysm

    International Nuclear Information System (INIS)

    Idei, Masaru; Yamane, Kanji; Okita, Shinji; Kumano, Kiyoshi; Nakae, Ryuta

    2009-01-01

    Meticulous clipping techniques are essential to obtain good results. Recently, the introduction of intravascular surgery for cerebral aneurysms has decreased the number of the direct clipping surgeries. And the increasing number of the lawsuits against doctors further discourages young surgeons from attempting clipping. As a result, young neurosurgeons, have less experience performing clipping. Therefore, we must learn clipping techniques from expert neurosurgeons under the limitation of having fewer opportunities to perform clipping surgery. In this paper, I present my experiences and discuss ways to obtain techniques for clipping surgery. I performed surgical clipping in 19 cases, 12 unruptured and 7 ruptured aneurysms, 7 males and 12 females aged from 36 to 79 years old (mean 61.9 years). Postoperatively, there were no symptomatic complications, but there were 2 asymptomatic infarctions that were revealed on CT scan. Intraoperative premature rupture occurred in 1 patient with a ruptured aneurysm. Techniques of manipulation with micro-forceps, suction and spatula are required for successful clipping. Off-the-job training of dissecting chicken wing arteries and rat abdominal aortas and vena cavas is useful. Moreover, actual experiences of surgical operations are essential. Surgical experiences raise the motivation of young neurosurgeons and encourage them to train more. We believe that this benign cycle contributes to meticulous surgical skills. (author)

  11. Evaluation of primary and secondary stability of titanium implants using different surgical techniques

    NARCIS (Netherlands)

    Tabassum, A.; Meijer, G.J.; Walboomers, X.F.; Jansen, J.A.

    2014-01-01

    OBJECTIVE: To investigate the influence of different surgical techniques on the primary and secondary implant stability using trabecular bone of goats as an implantation model. MATERIAL AND METHODS: In the iliac crest of eight goats, 48 cylindrical-screw-type implants with a diameter of 4.2 mm

  12. Outcome of Vaginoplasty in Male-to-Female Transgenders: A Systematic Review of Surgical Techniques

    NARCIS (Netherlands)

    Horbach, S.E.R.; Bouman, M.B.; Smit, J.M.; Özer, M.; Buncamper, M.E.; Mullender, M.G.

    2015-01-01

    Introduction: Gender reassignment surgery is the keystone of the treatment of transgender patients. For male-to-female transgenders, this involves the creation of a neovagina. Many surgical methods for vaginoplasty have been opted. The penile skin inversion technique is the method of choice for most

  13. Worldwide trends in surgical techniques in the treatment of esophageal and gastroesophageal junction cancer

    NARCIS (Netherlands)

    Haverkamp, L.; Seesing, M. F J; Ruurda, J. P.; Boone, J.; van Hillegersberg, R.

    The aim of this study was to evaluate the worldwide trends in surgical techniques for esophageal cancer surgery by comparing it to our survey from 2007. In addition, new questions were added for gastroesophageal junction (GEJ) cancer. An international survey on surgery of esophageal and GEJ cancer

  14. Testing of a new prototype surgical stapler that automates the rollover sleeve technique for venous anastomoses

    OpenAIRE

    PATRICIA B CARROLL; WERVISTON DEFARIA; CARLOS GANDIA; MARIANA BERHO; EVANGELOS MISIAKOS; ANDREAS G TZAKIS

    2006-01-01

    The creation of successful vascular anastomoses is of primary importance in many surgical fields. Numerous attempts to automate this process have been made. These techniques have slowly gained acceptance, but their use is still limited. This report details feasibility testing of a new prototype stapler that automates the rollover sleeve technique for venous vascular anastomoses. Male and female mongrel dogs (n=7) (25-32 kg) were used. A segment of the right (n=5) or left (n=2) iliac vein was ...

  15. Prepubertal gonadectomy in cats: different surgical techniques and comparison with gonadectomy at traditional age.

    Science.gov (United States)

    Porters, N; Polis, I; Moons, C; Duchateau, L; Goethals, K; Huyghe, S; de Rooster, H

    2014-09-06

    Feasibility, surgical time and complications of different surgical techniques for prepubertal gonadectomy (PPG; 8-12 weeks of age) in cats were studied and compared to gonadectomy at traditional age (TAG; 6-8 months of age). Kittens were randomly assigned to PPG or TAG. Ovarian pedicle haemostasis for PPG was achieved by ligatures (n=47), vascular clips (n=50), bipolar electrocoagulation (n=50), or pedicle tie (n=50); for TAG (n=34) ligatures were used. In male cats, PPG consisted of closed castration by spermatic cord knot (n=92) or ligature (n=91) while TAG (n=34) was an open castration by spermatic cord knot. A linear (surgical time) and a logistic regression (complications) model were designed. Significance was set at 0.05. For female PPG, clips and coagulation were the fastest procedures; placement of ligatures was most time-consuming. In male PPG, knot placement was significantly faster than ligation. In both sexes, very few intraoperative or wound complications were observed, irrespective of the surgical technique used. Surgical times in females (ligatures) as well as in males (knot) were significantly shorter for PPG than for TAG. PPG was as safe as TAG, yet took less time to perform and did not result in a greater rate of postoperative complications. British Veterinary Association.

  16. Vaginal-sparing ventral buccal mucosal graft urethroplasty for female urethral stricture: A novel modification of surgical technique

    Directory of Open Access Journals (Sweden)

    Nathan Hoag

    2016-07-01

    Full Text Available Purpose: To present a novel modification of surgical technique to treat female urethral stricture (FUS by a vaginal-sparing ventral buccal mucosal urethroplasty. Recurrent FUS represents an uncommon, though difficult clinical scenario to manage definitively. A variety of surgical techniques have been described to date, yet a lack of consensus on the optimal procedure persists. Materials and Methods: We present a 51-year-old female with urethral stricture involving the entire urethra. Suspected etiology was iatrogenic from cystoscopy 17 years prior. Since then, the patient had undergone at least 25 formal urethral dilations and periods of self-dilation. In lithotomy position, the urethra was dilated to accommodate forceps, and ventral urethrotomy carried out sharply, exposing a bed of periurethral tissue. Buccal mucosa was harvested, and a ventral inlay technique facilitated by a nasal speculum, was used to place the graft from the proximal urethra/bladder neck to urethral meatus without a vaginal incision. Graft was sutured into place, and urethral Foley catheter inserted. Results: The vaginal-sparing ventral buccal mucosal graft urethroplasty was deemed successful as of last follow-up. Flexible cystoscopy demonstrated patency of the repair at 6 months. At 10 months of follow-up, the patient was voiding well, with no urinary incontinence. No further interventions have been required. Conclusions: This case describes a novel modification of surgical technique for performing buccal mucosal urethroplasty for FUS. By avoiding incision of the vaginal mucosa, benefits may include reduced: morbidity, urinary incontinence, and wound complications including urethro-vaginal fistula.

  17. The first successful laparoscopic Whipple procedure at Hat Yai Hospital: surgical technique and a case report.

    Science.gov (United States)

    Khaimook, Araya; Borkird, Jumpot; Alapach, Sakda

    2010-09-01

    Whipple procedure is the most complex abdominal surgical procedure to treat periampullary carcinoma. With the benefit of minimally invasive approach, many institutes attempt to do Whipple procedure laparoscopically. However, only 146 cases of laparoscopic Whipple procedure have yet been reported in the literature worldwide between 1994 and 2008. The authors reported the first laparoscopic Whipple procedure at Hat Yai Hospital in December 2009. The patient was a 40-year-old, Thai-Muslim female, with the diagnosis of ampullary carcinoma. The operating time was 685 minutes. The patient was discharged on postoperative day 14 without serious complication. The surgical technique and postoperative progress of the patient were described.

  18. Useful surgical techniques for facial nerve preservation in tumorous intra-temporal lesions.

    Science.gov (United States)

    Kim, Jin; Moon, In Seok; Lee, Jong Dae; Shim, Dae Bo; Lee, Won-Sang

    2010-02-01

    The management of the facial nerve in tumorous temporal lesions is particularly challenging due to its complex anatomic location and potential postoperative complications, including permanent facial paralysis. The most important concern regarding surgical treatment of a tumorous temporal lesion is the inevitable facial paralysis caused by nerve injury during the tumor removal, especially in patients with minimal to no preoperative facial nerve dysfunction. We describe successful four cases in which various surgical techniques were developed for the preservation of the facial nerve in treatment of intratemporal tumorous lesions. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  19. Operation optimization of distributed generation using artificial intelligent techniques

    Directory of Open Access Journals (Sweden)

    Mahmoud H. Elkazaz

    2016-06-01

    Full Text Available Future smart grids will require an observable, controllable and flexible network architecture for reliable and efficient energy delivery. The use of artificial intelligence and advanced communication technologies is essential in building a fully automated system. This paper introduces a new technique for online optimal operation of distributed generation (DG resources, i.e. a hybrid fuel cell (FC and photovoltaic (PV system for residential applications. The proposed technique aims to minimize the total daily operating cost of a group of residential homes by managing the operation of embedded DG units remotely from a control centre. The target is formed as an objective function that is solved using genetic algorithm (GA optimization technique. The optimal settings of the DG units obtained from the optimization process are sent to each DG unit through a fully automated system. The results show that the proposed technique succeeded in defining the optimal operating points of the DGs that affect directly the total operating cost of the entire system.

  20. Rehabilitation with 4 zygomatic implants with a new surgical protocol using ultrasonic technique.

    Science.gov (United States)

    Mozzati, Marco; Mortellaro, Carmen; Arata, Valentina; Gallesio, Giorgia; Previgliano, Valter

    2015-05-01

    When the residual bone crest cannot allow the placement of standard implants, the treatment for complete arch rehabilitation of severely atrophic maxillae can be performed with 4 zygomatic implants (ZIs) and immediate function with predictable results in terms of aesthetics, function, and comfort for the patient. However, even if ZIs' rehabilitations showed a good success rate, this surgery is difficult and need a skillful operator. Complications in this kind of rehabilitation are not uncommon; the main difficulties can be related to the reduced surgical visibility and instrument control in a critical anatomic area. All the surgical protocols described in the literature used drilling techniques. Furthermore, the use of ultrasonic instruments in implant surgery compared with drilling instruments have shown advantages in many aspects of surgical procedures, tissues management, enhancement of control, surgical visualization, and healing. The aim of this study was to report on the preliminary experience using ultrasound technique for ZIs surgery in terms of safety and technical improvement. Ten consecutive patients with severely atrophic maxilla have been treated with 4 ZIs and immediate complete arch acrylic resin provisional prostheses. The patients were followed up from 30 to 32 months evaluating implant success, prosthetic success, and patient satisfaction with a questionnaire. No implants were lost during the study period, with a 100% implant and prosthetic success rate. Within the limitations of this preliminary study, these data indicate that ultrasonic implant site preparation for ZIs can be a good alternative to the drilling technique and an improvement for the surgeon.

  1. Pigment dispersion syndrome associated with intraocular lens implantation: a new surgical technique.

    Science.gov (United States)

    Canut Jordana, M Isabel; Pérez Formigó, Daniel; Abreu González, Rodrigo; Nadal Reus, Jeroni

    2010-11-11

    We report the case of a myopic patient who, after intraocular lens transplant in the posterior chamber, suffered elevated intraocular pressure due to pigment dispersion, with recurrent episodes of blurred vision. The patient was treated with a new surgical technique that can avoid potential iridolenticular contact. Complete ophthalmologic examination and optical coherence tomography (OCT) of the anterior segment were performed. Contact between the pigmentary epithelium and the iris with an intraocular lens was revealed by utrasound biomicroscopy and OCT. In this case, Nd:YAG laser iridotomy and laser iridoplasty were not effective for iridolenticular separation and control of the pigment dispersion. We propose a new technique: stitches on the surface of the iris to obtain good iridolenticular separation and good intraocular pressure control. Stitches on the iris surface should be considered as optional therapy in pigmentary glaucoma secondary to intraocular lens implantation. This surgical technique can avoid potential iridolenticular contacts more definitively.

  2. Measurement of blood flow through surgical anastomosis using the radioactive microsphere technique

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, S.J.; Delgado, G.; Butterfield, A.; Dritschilo, A.; Harbert, J.

    1985-10-01

    Two different radioactive microspheres ( U Ce and UWSc) were used to measure blood flow to an area of the large intestine in dogs before and after a surgical resection was performed with surgical staples. The healing of an anastomosis is theoretically related to the blood flow to the anastomotic site. Blood flow studies were conducted in three dogs using this technique. The average blood flow preoperatively was 0.558 mL/minute per gram and 1.04 mL/minute per gram postoperatively. These results indicate a statistically significant increase in blood flow at the anastomotic site six days after anastomosis when compared with the blood flow to the same area before any surgical procedures.

  3. Measurement of blood flow through surgical anastomosis using the radioactive microsphere technique

    International Nuclear Information System (INIS)

    Hummel, S.J.; Delgado, G.; Butterfield, A.; Dritschilo, A.; Harbert, J.

    1985-01-01

    Two different radioactive microspheres ( 141 Ce and 46 Sc) were used to measure blood flow to an area of the large intestine in dogs before and after a surgical resection was performed with surgical staples. The healing of an anastomosis is theoretically related to the blood flow to the anastomotic site. Blood flow studies were conducted in three dogs using this technique. The average blood flow preoperatively was 0.558 mL/minute per gram and 1.04 mL/minute per gram postoperatively. These results indicate a statistically significant increase in blood flow at the anastomotic site six days after anastomosis when compared with the blood flow to the same area before any surgical procedures

  4. An optimization planning technique for Suez Canal Network in Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Abou El-Ela, A.A.; El-Zeftawy, A.A.; Allam, S.M.; Atta, Gasir M. [Electrical Engineering Dept., Faculty of Eng., Shebin El-Kom (Egypt)

    2010-02-15

    This paper introduces a proposed optimization technique POT for predicting the peak load demand and planning of transmission line systems. Many of traditional methods have been presented for long-term load forecasting of electrical power systems. But, the results of these methods are approximated. Therefore, the artificial neural network (ANN) technique for long-term peak load forecasting is modified and discussed as a modern technique in long-term load forecasting. The modified technique is applied on the Egyptian electrical network dependent on its historical data to predict the electrical peak load demand forecasting up to year 2017. This technique is compared with extrapolation of trend curves as a traditional method. The POT is applied also to obtain the optimal planning of transmission lines for the 220 kV of Suez Canal Network (SCN) using the ANN technique. The minimization of the transmission network costs are considered as an objective function, while the transmission lines (TL) planning constraints are satisfied. Zafarana site on the Red Sea coast is considered as an optimal site for installing big wind farm (WF) units in Egypt. So, the POT is applied to plan both the peak load and the electrical transmission of SCN with and without considering WF to develop the impact of WF units on the electrical transmission system of Egypt, considering the reliability constraints which were taken as a separate model in the previous techniques. The application on SCN shows the capability and the efficiently of the proposed techniques to obtain the predicting peak load demand and the optimal planning of transmission lines of SCN up to year 2017. (author)

  5. Priority of surgical treatment techniques of full cartilage defects of knee joint

    Directory of Open Access Journals (Sweden)

    Андрій Вікторович Літовченко

    2015-10-01

    Full Text Available Aim. Surgical treatment of chondromalacia of knee joint cartilage is an actual problem of the modern orthopedics because the means of conservative therapy can be realized at an initial stage only and almost exhausted at the further ones. Imperfections of palliative surgical techniques are the short-term clinical effect and pathogenetic baselessness because surgical procedure is not directed on reparation of cartilaginous tissue. For today there are a lot of transplantation techniques that are used for biological renewal of articular surface with formation of hyaline or at least hyaline-like cartilage. The deep forage of cartilage defect bottom to the medullary canal is a perspective and priority technique.Methods. The results of treatment of 61 patients with chondromalacia of knee joint of 3-4 degree according to R. Outerbridge are the base of the work. 20 patients of every group underwent microfracturization of cartilage defect bottom and subchondral forage of defect zone. 21 patients underwent the deep forage of defect zone of knee joint according to an offered technique.Result. The results of treatment with microfracturization, subchondral forage and deep forage of defect zone indicate the more strong clinical effect especially in the last clinical group where good and satisfactory results ratios in the term of observation 18 and 24 month remain stable.Conclusions. Deep forage of cartilage defects zone is the most adequate reparative technique of the surgical treatment of local knee joint cartilage defects. Owing to this procedure the number of cells of reparative chondrogenesis predecessors is realized

  6. An improved technique for the prediction of optimal image resolution ...

    African Journals Online (AJOL)

    user

    2010-10-04

    Oct 4, 2010 ... Available online at http://www.academicjournals.org/AJEST ... robust technique for predicting optimal image resolution for the mapping of savannah ecosystems was developed. .... whether to purchase multi-spectral imagery acquired by GeoEye-2 ..... Analysis of the spectral behaviour of the pasture class in.

  7. [Multiple colonic anastomoses in the surgical treatment of short bowel syndrome. A new technique].

    Science.gov (United States)

    Robledo-Ogazón, Felipe; Becerril-Martínez, Guillermo; Hernández-Saldaña, Víctor; Zavala-Aznar, Marí Luisa; Bojalil-Durán, Luis

    2008-01-01

    Some surgical pathologies eventually require intestinal resection. This may lead to an extended procedure such as leaving 30 cm of proximal jejunum and left and sigmoid colon. One of the most important consequences of this type of resection is "intestinal failure" or short bowel syndrome. This complex syndrome leads to different metabolic and water and acid/base imbalances, as well as nutritional and immunological challenges along with the problem accompanying an abdomen subjected to many surgical procedures and high mortality. Many surgical techniques have been developed to improve quality of life of patients. We designed a non-transplant surgical approach and performed the procedure on two patients with postoperative short bowel syndrome with work can be performed by a large number of surgeons. The procedure has a low morbimortality rate and offers the opportunity for better control of metabolic and acid/base balance, intestinal transit and proper nutrition. We consider that this technique offers a new alternative for the complex management required by patients with short bowel syndrome and facilitates their long-term nutritional control.

  8. A novel surgical method for total nail ablation: Use of triple flap technique

    Directory of Open Access Journals (Sweden)

    Berna Aksoy

    2017-11-01

    Full Text Available Total nail ablation for the treatment of onychodystrophies can be performed by using chemicals, surgical resection or laser ablation of nail matrix. A female patient with bilateral severe onychodystrophy as a result of inadvertent previous nail surgeries was treated surgically. Proximal complete nail matrix resection and distal 10 mm wide transverse strip partial nail bed resection were performed. A 5 mm wide transverse strip of nail bed was left intact proximally. Proximal nail matrix defect was closed by using the skin of proximal nail fold. The distal nail bed defect was reconstructed by using triple flap technique which was composed of a main central advancement flap containing ventral toe skin and two side flaps containing nail fold skin. The patient healed without any problem and her nail problem was treated successfully. The cosmetic appearance of her first toes was acceptable. Surgical nail ablation followed by volar skin coverage of dorsal surface of the distal phalanx bone by using triple flap technique is an effective surgical treatment method for the correction of advanced nail plate deformities requiring total nail ablation. 

  9. Minimally invasive corticotomy in orthodontics: a new technique using a CAD/CAM surgical template.

    Science.gov (United States)

    Cassetta, M; Pandolfi, S; Giansanti, M

    2015-07-01

    Accelerating orthodontic tooth movement is a topical issue. Despite the different techniques described in the literature, the corticotomy is the only effective and safe means of accelerating orthodontic tooth movement. Although effective, the corticotomy presents significant postoperative discomfort. The aggressive nature of these particular methods, related to the elevation of mucoperiosteal flaps and to the length of the surgery, has resulted in reluctance to proceed with this technique among both patients and the dental community. To overcome the disadvantages of the corticotomy, this technical note describes an innovative, minimally invasive, flapless procedure combining piezoelectric surgical cortical micro-incisions with the use of a 3D Printed CAD/CAM surgical guide. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  10. Reversible hydronephrosis in the rat: a new surgical technique assessed by radioisotopic measurements

    International Nuclear Information System (INIS)

    Flam, T.; Venot, A.; Bariety, J.

    1984-01-01

    A new technique for experimental reversible hydronephrosis in the rat was developed. A noninvasive radioisotopic investigation, using Tc-99m dimercaptosuccinic acid, permitted sequential assessment of the separate renal function at different stages of the study. After 1 week of unilateral ureteral obstruction, reversibility was obtained by the removal of the obstructive device. Ten days after the obstruction release, the ipsilateral kidney had returned to 71 per cent of its preligation uptake value. Histological findings demonstrated the reversibility of the surgical obstruction

  11. A new surgical technique for concealed penis using an advanced musculocutaneous scrotal flap.

    Science.gov (United States)

    Han, Dong-Seok; Jang, Hoon; Youn, Chang-Shik; Yuk, Seung-Mo

    2015-06-19

    Until recently, no single, universally accepted surgical method has existed for all types of concealed penis repairs. We describe a new surgical technique for repairing concealed penis by using an advanced musculocutaneous scrotal flap. From January 2010 to June 2014, we evaluated 12 patients (12-40 years old) with concealed penises who were surgically treated with an advanced musculocutaneous scrotal flap technique after degloving through a ventral approach. All the patients were scheduled for regular follow-up at 6, 12, and 24 weeks postoperatively. The satisfaction grade for penile size, morphology, and voiding status were evaluated using a questionnaire preoperatively and at all of the follow-ups. Information regarding complications was obtained during the postoperative hospital stay and at all follow-ups. The patients' satisfaction grades, which included the penile size, morphology, and voiding status, improved postoperatively compared to those preoperatively. All patients had penile lymphedema postoperatively; however, this disappeared within 6 weeks. There were no complications such as skin necrosis and contracture, voiding difficulty, or erectile dysfunction. Our advanced musculocutaneous scrotal flap technique for concealed penis repair is technically easy and safe. In addition, it provides a good cosmetic appearance, functional outcomes and excellent postoperative satisfaction grades. Lastly, it seems applicable in any type of concealed penis, including cases in which the ventral skin defect is difficult to cover.

  12. Transtemporal amygdalohippocampectomy: a novel minimally-invasive technique with optimal clinical results and low cost

    Directory of Open Access Journals (Sweden)

    Juan Antonio Castro Flores

    Full Text Available ABSTRACT Mesial temporal sclerosis creates a focal epileptic syndrome that usually requires surgical resection of mesial temporal structures. Objective: To describe a novel operative technique for treatment of temporal lobe epilepsy and its clinical results. Methods: Prospective case-series at a single institution, performed by a single surgeon, from 2006 to 2012. A total of 120 patients were submitted to minimally-invasive keyhole transtemporal amygdalohippocampectomy. Results: Of the patients, 55% were male, and 85% had a right-sided disease. The first 70 surgeries had a mean surgical time of 2.51 hours, and the last 50 surgeries had a mean surgical time of 1.62 hours. There was 3.3% morbidity, and 5% mild temporal muscle atrophy. There was no visual field impairment. On the Engel Outcome Scale at the two-year follow-up, 71% of the patients were Class I, 21% were Class II, and 6% were Class III. Conclusion: This novel technique is feasible and reproducible, with optimal clinical results.

  13. An Image Morphing Technique Based on Optimal Mass Preserving Mapping

    Science.gov (United States)

    Zhu, Lei; Yang, Yan; Haker, Steven; Tannenbaum, Allen

    2013-01-01

    Image morphing, or image interpolation in the time domain, deals with the metamorphosis of one image into another. In this paper, a new class of image morphing algorithms is proposed based on the theory of optimal mass transport. The L2 mass moving energy functional is modified by adding an intensity penalizing term, in order to reduce the undesired double exposure effect. It is an intensity-based approach and, thus, is parameter free. The optimal warping function is computed using an iterative gradient descent approach. This proposed morphing method is also extended to doubly connected domains using a harmonic parameterization technique, along with finite-element methods. PMID:17547128

  14. TECHNIQUE OF OPTIMAL AUDIT PLANNING FOR INFORMATION SECURITY MANAGEMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    F. N. Shago

    2014-03-01

    Full Text Available Complication of information security management systems leads to the necessity of improving the scientific and methodological apparatus for these systems auditing. Planning is an important and determining part of information security management systems auditing. Efficiency of audit will be defined by the relation of the reached quality indicators to the spent resources. Thus, there is an important and urgent task of developing methods and techniques for optimization of the audit planning, making it possible to increase its effectiveness. The proposed technique gives the possibility to implement optimal distribution for planning time and material resources on audit stages on the basis of dynamics model for the ISMS quality. Special feature of the proposed approach is the usage of a priori data as well as a posteriori data for the initial audit planning, and also the plan adjustment after each audit event. This gives the possibility to optimize the usage of audit resources in accordance with the selected criteria. Application examples of the technique are given while planning audit information security management system of the organization. The result of computational experiment based on the proposed technique showed that the time (cost audit costs can be reduced by 10-15% and, consequently, quality assessments obtained through audit resources allocation can be improved with respect to well-known methods of audit planning.

  15. Choice of a General Anesthesia Technique in the Surgical Treatment of Postinfarct Left Ventricular Aneurysms

    Directory of Open Access Journals (Sweden)

    N. A. Karpun

    2005-01-01

    Full Text Available Objective. To choose the optimum technique of general anesthesia in the surgical treatment of patients with postinfarct left ventricular aneurysms (PLVA.Materials and methods. Fifty-four patients operated on for PLVA were examined. They were divided into 4 groups according to the basic technique of general anesthesia: 1 intravenous anesthesia based on propofol and fentanyl; 2 inhalation sevoflurane anesthesia with fentanyl enhancement of the analgesic component; 3 inhalation isoflurane anesthesia with fentanyl enhancement of the analgesic component; 4 general anesthesia in combination with epidural blockade. Central hemodynamics was investigated by the thermodilution technique and the perioperative period was also studied.Results and discussion. None of the general anesthesia techniques affected the development of perioperative complications. However, with decreased myocardial reserves, high thoracic epidural anesthesia should be applied with caution as it causes a significant desympathization, which may lead to impairments of the autoregulatory mechanisms of coronary blood flow and aggravate existing contractile disorders. Intravenous and inhalation anesthesia techniques provide a fair hemodynamic stability at all stages of surgical treatment. Inhalation anesthesia has a number of advantages: less cost and the possibility of rapid activation of patients in the early postoperative period.

  16. "TuNa-saving" endoscopic medial maxillectomy: a surgical technique for maxillary inverted papilloma.

    Science.gov (United States)

    Pagella, Fabio; Pusateri, Alessandro; Matti, Elina; Avato, Irene; Zaccari, Dario; Emanuelli, Enzo; Volo, Tiziana; Cazzador, Diego; Citraro, Leonardo; Ricci, Giampiero; Tomacelli, Giovanni Leo

    2017-07-01

    The maxillary sinus is the most common site of sinonasal inverted papilloma. Endoscopic sinus surgery, in particular endoscopic medial maxillectomy, is currently the gold standard for treatment of maxillary sinus papilloma. Although a common technique, complications such as stenosis of the lacrimal pathway and consequent development of epiphora are still possible. To avoid these problems, we propose a modification of this surgical technique that preserves the head of the inferior turbinate and the nasolacrimal duct. A retrospective analysis was performed on patients treated for maxillary inverted papilloma in three tertiary medical centres between 2006 and 2014. Pedicle-oriented endoscopic surgery principles were applied and, in select cases where the tumour pedicle was located on the anterior wall, a modified endoscopic medial maxillectomy was carried out as described in this paper. From 2006 to 2014 a total of 84 patients were treated. A standard endoscopic medial maxillectomy was performed in 55 patients (65.4%), while the remaining 29 (34.6%) had a modified technique performed. Three recurrences (3/84; 3.6%) were observed after a minimum follow-up of 24 months. A new surgical approach for select cases of maxillary sinus inverted papilloma is proposed in this paper. In this technique, the endoscopic medial maxillectomy was performed while preserving the head of the inferior turbinate and the nasolacrimal duct ("TuNa-saving"). This technique allowed for good visualization of the maxillary sinus, good oncological control and a reduction in the rate of complications.

  17. [Management of spinal metastasis by minimal invasive surgery technique: Surgical principles, indications: A literature review].

    Science.gov (United States)

    Toquart, A; Graillon, T; Mansouri, N; Adetchessi, T; Blondel, B; Fuentes, S

    2016-06-01

    Spinal metastasis are getting more frequent. This raises the question of pain and neurological complications, which worsen the functional and survival prognosis of this oncological population patients. The surgical treatment must be the most complete as possible: to decompress and stabilize without delaying the management of the oncological disease. Minimal invasive surgery techniques are by definition, less harmful on musculocutaneous plan than opened ones, with a comparable efficiency demonstrated in degenerative and traumatic surgery. So they seem to be applicable and appropriate to this patient population. We detailed different minimal invasive techniques proposed in the management of spinal metastasis. For this, we used our experience developed in degenerative and traumatic pathologies, and we also referred to many authors, establishing a literature review thanks to Pubmed, Embase. Thirty eight articles were selected and allowed us to describe different techniques: percutaneous methods such as vertebro-/kyphoplasty and osteosynthesis, as well as mini-opened surgery, through a posterior or anterior way. We propose a surgical approach using these minimal invasive techniques, first according to the predominant symptom (pain or neurologic failure), then characteristics of the lesions (number, topography, type…) and the deformity degree. Whatever the technique, the main goal is to stabilize and decompress, in order to maintain a good quality of life for these fragile patients, without delaying the medical management of the oncological disease. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Optimization of Hydraulic Machinery Bladings by Multilevel CFD Techniques

    Directory of Open Access Journals (Sweden)

    Thum Susanne

    2005-01-01

    Full Text Available The numerical design optimization for complex hydraulic machinery bladings requires a high number of design parameters and the use of a precise CFD solver yielding high computational costs. To reduce the CPU time needed, a multilevel CFD method has been developed. First of all, the 3D blade geometry is parametrized by means of a geometric design tool to reduce the number of design parameters. To keep geometric accuracy, a special B-spline modification technique has been developed. On the first optimization level, a quasi-3D Euler code (EQ3D is applied. To guarantee a sufficiently accurate result, the code is calibrated by a Navier-Stokes recalculation of the initial design and can be recalibrated after a number of optimization steps by another Navier-Stokes computation. After having got a convergent solution, the optimization process is repeated on the second level using a full 3D Euler code yielding a more accurate flow prediction. Finally, a 3D Navier-Stokes code is applied on the third level to search for the optimum optimorum by means of a fine-tuning of the geometrical parameters. To show the potential of the developed optimization system, the runner blading of a water turbine having a specific speed n q = 41 1 / min was optimized applying the multilevel approach.

  19. Use of the 3D surgical modelling technique with open-source software for mandibular fibula free flap reconstruction and its surgical guides.

    Science.gov (United States)

    Ganry, L; Hersant, B; Quilichini, J; Leyder, P; Meningaud, J P

    2017-06-01

    Tridimensional (3D) surgical modelling is a necessary step to create 3D-printed surgical tools, and expensive professional software is generally needed. Open-source software are functional, reliable, updated, may be downloaded for free and used to produce 3D models. Few surgical teams have used free solutions for mastering 3D surgical modelling for reconstructive surgery with osseous free flaps. We described an Open-source software 3D surgical modelling protocol to perform a fast and nearly free mandibular reconstruction with microvascular fibula free flap and its surgical guides, with no need for engineering support. Four successive specialised Open-source software were used to perform our 3D modelling: OsiriX ® , Meshlab ® , Netfabb ® and Blender ® . Digital Imaging and Communications in Medicine (DICOM) data on patient skull and fibula, obtained with a computerised tomography (CT) scan, were needed. The 3D modelling of the reconstructed mandible and its surgical guides were created. This new strategy may improve surgical management in Oral and Craniomaxillofacial surgery. Further clinical studies are needed to demonstrate the feasibility, reproducibility, transfer of know how and benefits of this technique. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. Impact of robotic technique and surgical volume on the cost of radical prostatectomy.

    Science.gov (United States)

    Hyams, Elias S; Mullins, Jeffrey K; Pierorazio, Phillip M; Partin, Alan W; Allaf, Mohamad E; Matlaga, Brian R

    2013-03-01

    Our present understanding of the effect of robotic surgery and surgical volume on the cost of radical prostatectomy (RP) is limited. Given the increasing pressures placed on healthcare resource utilization, such determinations of healthcare value are becoming increasingly important. Therefore, we performed a study to define the effect of robotic technology and surgical volume on the cost of RP. The state of Maryland mandates that all acute-care hospitals report encounter-level and hospital discharge data to the Health Service Cost Review Commission (HSCRC). The HSCRC was queried for men undergoing RP between 2008 and 2011 (the period during which robot-assisted laparoscopic radical prostatectomy [RALRP] was coded separately). High-volume hospitals were defined as >60 cases per year, and high-volume surgeons were defined as >40 cases per year. Multivariate regression analysis was performed to evaluate whether robotic technique and high surgical volume impacted the cost of RP. There were 1499 patients who underwent RALRP and 2565 who underwent radical retropubic prostatectomy (RRP) during the study period. The total cost for RALRP was higher than for RRP ($14,000 vs 10,100; Probotic surgery has come to dominate the healthcare marketplace, strategies to increase the role of high-volume providers may be needed to improve the cost-effectiveness of prostate cancer surgical therapy.

  1. Preoperative Nutritional Optimization for Crohn's Disease Patients Can Improve Surgical Outcome.

    Science.gov (United States)

    Dreznik, Yael; Horesh, Nir; Gutman, Mordechai; Gravetz, Aviad; Amiel, Imri; Jacobi, Harel; Zmora, Oded; Rosin, Danny

    2017-11-01

    Preoperative preparation of patients with Crohn's disease is challenging and there are no specific guidelines regarding nutritional support. The aim of this study was to assess whether preoperative nutritional support influenced the postoperative outcome. A retrospective, cohort study including all Crohn's disease patients who underwent abdominal surgery between 2008 and 2014 was conducted. Patients' characteristics and clinical and surgical data were recorded and analyzed. Eighty-seven patients were included in the study. Thirty-seven patients (42.5%) received preoperative nutritional support (mean albumin level 3.14 vs. 3.5 mg/dL in the non-optimized group; p nutritional status prior to surgery. Preoperative albumin level, after adequate nutritional preparation, was similar between the 2 groups. The 2 groups differ neither in demographic and surgical data, overall post-op complication (p = 0.85), Clavien-Dindo score (p = 0.42), and length of stay (p = 0.1). Readmission rate was higher in the non-optimized group (p = 0.047). Nutritional support can minimize postoperative complications in patients with low albumin levels. Nutritional status should be optimized in order to avoid hazardous complications. © 2017 S. Karger AG, Basel.

  2. Surgical techniques for the treatment of ankyloglossia in children: a case series

    Directory of Open Access Journals (Sweden)

    Marina Azevedo JUNQUEIRA

    2014-06-01

    Full Text Available This paper reports a series of clinical cases of ankyloglossia in children, which were approached by different techniques: frenotomy and frenectomy with the use of one hemostat, two hemostats, a groove director or laser. Information on the indications, contraindications, advantages and disadvantages of the techniques was also presented. Children diagnosed with ankyloglossia were subjected to different surgical procedures. The choice of the techniques was based on the age of the patient, length of the frenulum and availability of the instruments and equipment. All the techniques presented are successful for the treatment of ankyloglossia and require a skilled professional. Laser may be considered a simple and safe alternative for children while reducing the amount of local anesthetics needed, the bleeding and the chances of infection, swelling and discomfort.

  3. A decoupled power flow algorithm using particle swarm optimization technique

    International Nuclear Information System (INIS)

    Acharjee, P.; Goswami, S.K.

    2009-01-01

    A robust, nondivergent power flow method has been developed using the particle swarm optimization (PSO) technique. The decoupling properties between the power system quantities have been exploited in developing the power flow algorithm. The speed of the power flow algorithm has been improved using a simple perturbation technique. The basic power flow algorithm and the improvement scheme have been designed to retain the simplicity of the evolutionary approach. The power flow is rugged, can determine the critical loading conditions and also can handle the flexible alternating current transmission system (FACTS) devices efficiently. Test results on standard test systems show that the proposed method can find the solution when the standard power flows fail.

  4. Quantitative Portfolio Optimization Techniques Applied to the Brazilian Stock Market

    Directory of Open Access Journals (Sweden)

    André Alves Portela Santos

    2012-09-01

    Full Text Available In this paper we assess the out-of-sample performance of two alternative quantitative portfolio optimization techniques - mean-variance and minimum variance optimization – and compare their performance with respect to a naive 1/N (or equally-weighted portfolio and also to the market portfolio given by the Ibovespa. We focus on short selling-constrained portfolios and consider alternative estimators for the covariance matrices: sample covariance matrix, RiskMetrics, and three covariance estimators proposed by Ledoit and Wolf (2003, Ledoit and Wolf (2004a and Ledoit and Wolf (2004b. Taking into account alternative portfolio re-balancing frequencies, we compute out-of-sample performance statistics which indicate that the quantitative approaches delivered improved results in terms of lower portfolio volatility and better risk-adjusted returns. Moreover, the use of more sophisticated estimators for the covariance matrix generated optimal portfolios with lower turnover over time.

  5. Material saving by means of CWR technology using optimization techniques

    Science.gov (United States)

    Pérez, Iñaki; Ambrosio, Cristina

    2017-10-01

    Material saving is currently a must for the forging companies, as material costs sum up to 50% for parts made of steel and up to 90% in other materials like titanium. For long products, cross wedge rolling (CWR) technology can be used to obtain forging preforms with a suitable distribution of the material along its own axis. However, defining the correct preform dimensions is not an easy task and it could need an intensive trial-and-error campaign. To speed up the preform definition, it is necessary to apply optimization techniques on Finite Element Models (FEM) able to reproduce the material behaviour when being rolled. Meta-models Assisted Evolution Strategies (MAES), that combine evolutionary algorithms with Kriging meta-models, are implemented in FORGE® software and they allow reducing optimization computation costs in a relevant way. The paper shows the application of these optimization techniques to the definition of the right preform for a shaft from a vehicle of the agricultural sector. First, the current forging process, based on obtaining the forging preform by means of an open die forging operation, is showed. Then, the CWR preform optimization is developed by using the above mentioned optimization techniques. The objective is to reduce, as much as possible, the initial billet weight, so that a calculation of flash weight reduction due to the use of the proposed preform is stated. Finally, a simulation of CWR process for the defined preform is carried out to check that most common failures (necking, spirals,..) in CWR do not appear in this case.

  6. Frequency of lingual nerve injury in mandibular third molar extraction: A comparison of two surgical techniques

    International Nuclear Information System (INIS)

    Shad, S.; Abbasi, M.M.

    2015-01-01

    Background: Surgical removal of impacted mandibular third molar is associated with a number of complications including postoperative bleeding, dry socket, postoperative infection, and injury to regional nerves. Lingual nerve damage is one of the main complications. To prevent this complication different techniques had been used. Lingual flap reflection is one of these procedures in which lingual soft tissue is reflected and retracted deliberately, the nerve is identified and is kept out of the surgical field. The objective of this study was to evaluate a surgical technique for third molar removal which is associated with minimum frequency of lingual nerve damage. Method: A randomized controlled trial was performed. A total of 380 patients with impacted mandibular third molars were included in this study. Each patient was allotted randomly by blocked randomization to group A where procedure was performed by reflection and retraction of lingual flap in addition to buccal flap and group B where procedure was performed by retraction of buccal flap only. Results: Lingual nerve damage occurred in 8.94 percentage in Group A in which lingual flap retraction was performed but damage was reversible. In group B, 2.63 percentage lingual nerve damage was observed and nature of damage was permanent. The difference was statistically significant (p=0.008). Conclusions: Lingual flap retraction poses 3.4 times increased risk of lingual nerve damage during extraction of mandibular third molar when lingual flap is retracted but the nature of damage is reversible. (author)

  7. Novel optimization technique of isolated microgrid with hydrogen energy storage.

    Science.gov (United States)

    Beshr, Eman Hassan; Abdelghany, Hazem; Eteiba, Mahmoud

    2018-01-01

    This paper presents a novel optimization technique for energy management studies of an isolated microgrid. The system is supplied by various Distributed Energy Resources (DERs), Diesel Generator (DG), a Wind Turbine Generator (WTG), Photovoltaic (PV) arrays and supported by fuel cell/electrolyzer Hydrogen storage system for short term storage. Multi-objective optimization is used through non-dominated sorting genetic algorithm to suit the load requirements under the given constraints. A novel multi-objective flower pollination algorithm is utilized to check the results. The Pros and cons of the two optimization techniques are compared and evaluated. An isolated microgrid is modelled using MATLAB software package, dispatch of active/reactive power, optimal load flow analysis with slack bus selection are carried out to be able to minimize fuel cost and line losses under realistic constraints. The performance of the system is studied and analyzed during both summer and winter conditions and three case studies are presented for each condition. The modified IEEE 15 bus system is used to validate the proposed algorithm.

  8. Electrostatic afocal-zoom lens design using computer optimization technique

    Energy Technology Data Exchange (ETDEWEB)

    Sise, Omer, E-mail: omersise@gmail.com

    2014-12-15

    Highlights: • We describe the detailed design of a five-element electrostatic afocal-zoom lens. • The simplex optimization is used to optimize lens voltages. • The method can be applied to multi-element electrostatic lenses. - Abstract: Electron optics is the key to the successful operation of electron collision experiments where well designed electrostatic lenses are needed to drive electron beam before and after the collision. In this work, the imaging properties and aberration analysis of an electrostatic afocal-zoom lens design were investigated using a computer optimization technique. We have found a whole new range of voltage combinations that has gone unnoticed until now. A full range of voltage ratios and spherical and chromatic aberration coefficients were systematically analyzed with a range of magnifications between 0.3 and 3.2. The grid-shadow evaluation was also employed to show the effect of spherical aberration. The technique is found to be useful for searching the optimal configuration in a multi-element lens system.

  9. Novel optimization technique of isolated microgrid with hydrogen energy storage.

    Directory of Open Access Journals (Sweden)

    Eman Hassan Beshr

    Full Text Available This paper presents a novel optimization technique for energy management studies of an isolated microgrid. The system is supplied by various Distributed Energy Resources (DERs, Diesel Generator (DG, a Wind Turbine Generator (WTG, Photovoltaic (PV arrays and supported by fuel cell/electrolyzer Hydrogen storage system for short term storage. Multi-objective optimization is used through non-dominated sorting genetic algorithm to suit the load requirements under the given constraints. A novel multi-objective flower pollination algorithm is utilized to check the results. The Pros and cons of the two optimization techniques are compared and evaluated. An isolated microgrid is modelled using MATLAB software package, dispatch of active/reactive power, optimal load flow analysis with slack bus selection are carried out to be able to minimize fuel cost and line losses under realistic constraints. The performance of the system is studied and analyzed during both summer and winter conditions and three case studies are presented for each condition. The modified IEEE 15 bus system is used to validate the proposed algorithm.

  10. Surgical techniques and curative effect of carotid endarterectomy for carotid artery stenosis

    Directory of Open Access Journals (Sweden)

    Min HAN

    2014-02-01

    Full Text Available Objective To investigate the surgical techniques of carotid endarterectomy (CEA for treating carotid artery stenosis, in order to improve the surgical efficacy and reduce intraoperative adverse events and complications after operation. Methods Retrospective analysis was carried out on surgical data of 53 cases who were performed CEA from October 2010 to October 2013 in Department of Neurosurgery in Tianjin Huanhu Hospital. There were 39 males and 14 females, aged from 40 to 78 years old and mean age (60.34 ± 8.92 years old; the course of disease was from 2 d to 4 years. Twenty-six cases were diagnosed as right carotid stenosis, 15 cases left carotid stenosis and 12 cases double-sided carotid stenosis. Among all of those cases, 35 cases were diagnosed as moderate stenosis (30%-69%, 16 cases severe stenosis (70%-99% , and 2 cases complete occlusion. Results Among 53 patients, 50 patients underwent CEA; 2 cases underwent CEA and aneurysm clipping; one case underwent stent removal surgery and CEA because restenosis was found after carotid artery stenting (CAS. Postoperative neck CTA and fMRI showed good morphology of carotid artery, fluent blood flow and improved cerebral perfusion after operation. All of those patients were followed up for 3 to 24 months. One case died of myocardial infarction; 2 cases appeared skin numbness on the operating side of the neck, and the symptom disappeared 3 months later; one case appeared hoarseness after operation; 3 cases experienced mild transient ischemic attack (TIA and the symptom disappeared 2 months later. No case of stroke was found. Conclusions CEA is a safe and effective surgical approach to treat carotid stenosis. Correct and reasonable choices of the surgical indications and skilled surgical technique are the key to ensure the success of operation and to improve efficacy of the therapy. doi:10.3969/j.issn.1672-6731.2014.02.006Video: http://www.cjcnn.org/index.php/cjcnn/pages/view/v14n2a6

  11. Congenital completely buried penis in boys: anatomical basis and surgical technique.

    Science.gov (United States)

    Liu, Xing; He, Da-wei; Hua, Yi; Zhang, De-ying; Wei, Guang-hui

    2013-07-01

    WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Surgical correction of the congenital completely buried penis (CCBP) is a difficult challenge and there is no unanimous consensus about the surgical 'gold standard' and patient eligibility for surgery. In the present study, dysgenetic fundiform ligaments were found to be attached to the distal or middle shaft of the penis. This abnormality can be successfully corrected by releasing the fundiform ligament and mobilising the scrotal skin to cover the length of the penile shaft. The study shows that the paucity and traction of the penile skin and an abnormal fundiform ligament are important anatomical defects in CCBP. Dorsal curve and severe shortage of penile skin in erectile conditions are the main indications for surgical correction. To present our experience of anatomical findings for congenital completely buried penis (CCBP), which has no unanimous consensus regarding the 'gold standard' for surgical correction and patient eligibility, by providing our surgical technique and illustrations. Between February 2006 and February 2011, 22 children with a median (range) age of 4.2 (2.5-5.8) years, with CCBP underwent surgical correction by one surgeon. Toilet training and photographs of morning erections by parents were advised before surgery. The abnormal anatomical structure of buried penis during the operation was observed. The technique consisted of the release of the fundiform ligament, fixation of the subcutaneous penile skin at the base of the degloved penis, penoscrotal Z-plasty and mobilisation of the penile and scrotal skin to cover the penile shaft. In reflex erectile conditions, CCBP presents varying degrees of dorsal curve and shortage of penile skin. Dysgenetic fundiform ligaments were found to be attached to the distal or middle shaft of the penis in all patients. All wounds healed well and the cosmetic outcome was good at 6-month follow-up after the repair. The appearance of the dorsal curve in

  12. Intestinal vaginoplasty revisited: a review of surgical techniques, complications, and sexual function.

    Science.gov (United States)

    Bouman, Mark-Bram; van Zeijl, Michiel C T; Buncamper, Marlon E; Meijerink, Wilhelmus J H J; van Bodegraven, Ad A; Mullender, Margriet G

    2014-07-01

    Vaginal (re)construction is essential for the psychological well-being of biological women with a dysfunctional vagina and male-to-female transgender women. However, the preferred method for vagina (re)construction with respect to functional as well as aesthetic outcomes is debated. Regarding intestinal vaginoplasty, despite the asserted advantages, the need for intestinal surgery and subsequent risk of diversion colitis are often-mentioned concerns. The outcomes of vaginal reconstructive surgery need to be appraised in order to improve understanding of pros and cons. To review literature on surgical techniques and clinical outcomes of intestinal vaginoplasty. Electronic databases and reference lists of published articles were searched for primary studies on intestinal vaginoplasty. Studies were included if these included at least five patients and had a minimal follow-up period of 1 year. No constraints were imposed with regard to patient age, indication for vaginoplasty, or applied surgical technique. Outcome measures were extracted and analyzed. Main outcome measures were surgical procedure, clinical outcomes, and outcomes concerning sexual health and quality of life. Twenty-one studies on intestinal vaginoplasty were included (including 894 patients in total). All studies had a retrospective design and were of low quality. Prevalence and severity of procedure-related complications were low. The main postoperative complication was introital stenosis, necessitating surgical correction in 4.1% of sigmoid-derived and 1.2% of ileum-derived vaginoplasties. Neither diversion colitis nor cancer was reported. Sexual satisfaction rate was high, but standardized questionnaires were rarely used. Quality of life was not reported. Based on evidence presently available, it seems that intestinal vaginoplasty is associated with low complication rates. To substantiate these findings and to obtain information about functional outcomes and quality of life, prospective studies

  13. Promoting teamwork and surgical optimization: combining TeamSTEPPS with a specialty team protocol.

    Science.gov (United States)

    Tibbs, Sheila Marie; Moss, Jacqueline

    2014-11-01

    This quality improvement project was a 300-day descriptive preintervention and postintervention comparison consisting of a convenience sample of 18 gynecology surgical team members. We administered the Team Strategies & Tools to Enhance Performance and Patient Safety (TeamSTEPPS®) Teamwork Perception Questionnaire to measure the perception of teamwork. In addition, we collected data regarding rates of compliance (ie, huddle, time out) and measurable surgical procedure times. Results showed a statistically significant increase in the number of team members present for each procedure, 2.34 μ before compared with 2.61 μ after (P = .038), and in the final time-out (FTO) compliance as a result of a clarification of the definition of FTO, 1.05 μ before compared with 1.18 μ after (P = .004). Additionally, there was improvement in staff members' perception of teamwork. The implementation of team training, protocols, and algorithms can enhance surgical optimization, communication, and work relationships. Copyright © 2014 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  14. Brachial plexus surgery: the role of the surgical technique for improvement of the functional outcome

    Directory of Open Access Journals (Sweden)

    Leandro Pretto Flores

    2011-08-01

    Full Text Available OBJECTIVE: The study aims to demonstrate the techniques employed in surgery of the brachial plexus that are associated to evidence-based improvement of the functional outcome of these patients. METHOD: A retrospective study of one hundred cases of traumatic brachial plexus injuries. Comparison between the postoperative outcomes associated to some different surgical techniques was demonstrated. RESULTS: The technique of proximal nerve roots grafting was associated to good results in about 70% of the cases. Significantly better outcomes were associated to the Oberlin's procedure and the Sansak's procedure, while the improvement of outcomes associated to phrenic to musculocutaneous nerve and the accessory to suprascapular nerve transfer did not reach statistical significance. Reinnervation of the hand was observed in less than 30% of the cases. CONCLUSION: Brachial plexus surgery renders satisfactory results for reinnervation of the proximal musculature of the upper limb, however the same good outcomes are not usually associated to the reinnervation of the hand.

  15. When Is the Optimal Timing of Surgical Intervention for Severe Functional Tricuspid Regurgitation?

    Directory of Open Access Journals (Sweden)

    Nobuhiro Nakanishi

    2017-01-01

    Full Text Available Functional tricuspid regurgitation (TR is a serious pathology to be noted for severe right heart failure (HF and poor prognosis; however, the conventional assessment of TR has some limitations and the optimal timing of surgical intervention remains unclear. A 79-year-old Japanese female was admitted to our hospital to undergo cardiac surgery, because edema gradually got worse despite the increase in diuretics. She had a history of atrial fibrillation (AF and chronic HF due to severe TR and had been treated with a furosemide for leg edema 4 years ago. A transthoracic echocardiogram (TTE, transesophageal echocardiogram, cardiac magnetic resonance imaging, and cardiac pool scintigraphy demonstrated severe functional TR with tricuspid annular dilation, insufficient tricuspid valve coaptation, and reduced right ventricular ejection fraction (EF but preserved left ventricular EF. In addition, Swan-Ganz catheter study showed normal pulmonary arterial wedge pressure and mean pulmonary arterial pressure. Tricuspid ring annuloplasty was performed with MC3 ring. Postoperative TTE showed trivial TR, and she had no edema with normal sinus rhythm two months later. Annuloplasty to severe functional TR caused by tricuspid annular dilation due to AF dramatically improved right HF. Cardiologist should pay strict attention to the optimal timing of surgical intervention for TR.

  16. Towards reducing thrombogenicity of LVAD therapy: optimizing surgical and patient management strategies

    Science.gov (United States)

    Chivukula, Venkat Keshav; Lafzi, Ali; Mokadam, Nahush; Beckman, Jennifer; Mahr, Claudius; Aliseda, Alberto

    2017-11-01

    Unfavourable hemodynamics in heart failure patients implanted with left ventricular assist devices (LVAD), due to non-optimal surgical configurations and patient management, strongly influence thrombogenicity. This is consistent with the increase in devastating thromboembolic complications (specifically thrombosis and stroke) in patients, even as the risk of thrombosis inside the device decreases with modern designs. Inflow cannula and outflow graft surgical configurations have been optimized via patient-specific modeling that computes the thrombogenic potential with a combination of Eulerian (endothelial) wall shear stress and Lagrangian (platelet shear history) tracking. Using this view of hemodynamics, the benefits of intermittent aortic valve opening (promoting washout and reducing stagnant flow in the aortic valve region) have been assessed in managing the patient's residual native cardiac output. The use of this methodology to understand the contribution of the hemodynamics in the flow surrounding the LVAD itself to thrombogenesis show promise in developing holistic patient-specific management strategies to minimize stroke risk and enhance efficacy of LVAD therapy. Funded in part by an AHA postdoctoral fellowship 16POST30520004.

  17. Testing of a new prototype surgical stapler that automates the rollover sleeve technique for venous anastomoses

    Directory of Open Access Journals (Sweden)

    PATRICIA B CARROLL

    2006-01-01

    Full Text Available The creation of successful vascular anastomoses is of primary importance in many surgical fields. Numerous attempts to automate this process have been made. These techniques have slowly gained acceptance, but their use is still limited. This report details feasibility testing of a new prototype stapler that automates the rollover sleeve technique for venous vascular anastomoses. Male and female mongrel dogs (n=7 (25-32 kg were used. A segment of the right (n=5 or left (n=2 iliac vein was harvested for interposition grafts after the contra lateral side was transected. In each dog, two end-to-end venous anastomoses at the interposition grafts were performed. The standard anastomosis employed continuous mattress sutures. The experimental anastomosis was performed with a new prototype surgical stapler. The stapled anastomosis was proximal and the sutured was distal. In all experiments, it was possible to perform the experimental anastomosis with the stapler. Complications included two small leaks, one due to misfiring of a single pin in one experimental site. These leaks required suture reinforcement. One dog died of hemorrhage due to a slipped suture at the vein harvest site. One vein had thrombus seen at the sutured site although no technical abnormalities at either of the anastomoses could be found. After two weeks, grafts were inspected grossly and histologically. Healing appeared normal. There was a trend for less inflammatory cells infiltrating stapled sites; however, this was not statistically significant. The experiments demonstrate that this device can automate the rollover sleeve technique for venous anastomoses.

  18. Testing of a new prototype surgical stapler that automates the rollover sleeve technique for venous anastomoses.

    Science.gov (United States)

    Carroll, Patricia B; Defaria, Werviston; Gandia, Carlos; Berho, Mariana; Misiakos, Evangelos; Tzakis, Andreas G

    2006-01-01

    The creation of successful vascular anastomoses is of primary importance in many surgical fields. Numerous attempts to automate this process have been made. These techniques have slowly gained acceptance, but their use is still limited. This report details feasibility testing of a new prototype stapler that automates the rollover sleeve technique for venous vascular anastomoses. Male and female mongrel dogs (n=7) (25-32 kg) were used. A segment of the right (n=5) or left (n=2) iliac vein was harvested for interposition grafts after the contra lateral side was transected. In each dog, two end-to-end venous anastomoses at the interposition grafts were performed. The standard anastomosis employed continuous mattress sutures. The experimental anastomosis was performed with a new prototype surgical stapler. The stapled anastomosis was proximal and the sutured was distal. In all experiments, it was possible to perform the experimental anastomosis with the stapler. Complications included two small leaks, one due to misfiring of a single pin in one experimental site. These leaks required suture reinforcement. One dog died of hemorrhage due to a slipped suture at the vein harvest site. One vein had thrombus seen at the sutured site although no technical abnormalities at either of the anastomoses could be found. After two weeks, grafts were inspected grossly and histologically. Healing appeared normal. There was a trend for less inflammatory cells infiltrating stapled sites; however, this was not statistically significant. The experiments demonstrate that this device can automate the rollover sleeve technique for venous anastomoses.

  19. Pigment dispersion syndrome associated with intraocular lens implantation: a new surgical technique

    Directory of Open Access Journals (Sweden)

    M Isabel Canut Jordana

    2010-11-01

    Full Text Available M Isabel Canut Jordana1, Daniel Pérez Formigó1, Rodrigo Abreu González2, Jeroni Nadal Reus11Barraquer Ophthalmology Centre, Barcelona, Spain; 2University Hospital of La Candelaria, Tenerife, SpainAims: We report the case of a myopic patient who, after intraocular lens transplant in the posterior chamber, suffered elevated intraocular pressure due to pigment dispersion, with recurrent episodes of blurred vision. The patient was treated with a new surgical technique that can avoid potential iridolenticular contact.Methods: Complete ophthalmologic examination and optical coherence tomography (OCT of the anterior segment were performed.Results: Contact between the pigmentary epithelium and the iris with an intraocular lens was revealed by utrasound biomicroscopy and OCT. In this case, Nd:YAG laser iridotomy and laser iridoplasty were not effective for iridolenticular separation and control of the pigment dispersion. We propose a new technique: stitches on the surface of the iris to obtain good iridolenticular separation and good intraocular pressure control.Conclusion: Stitches on the iris surface should be considered as optional therapy in pigmentary glaucoma secondary to intraocular lens implantation. This surgical technique can avoid potential iridolenticular contacts more definitively.Keywords: pigmentary glaucoma, intraocular lens, optical coherence tomography, laser

  20. Evaluation of different surgical techniques in the management of subluxated cataractous lens.

    Science.gov (United States)

    Aldakaf, A; Bakir, H; Almogahed, A; Carstocea, Benone

    2007-01-01

    To compare and evaluate the outcome of different surgical techniques in the management of subluxated cataractous lens. This retrospective study included 18 eyes of 18 patients with subluxated cataracts of varying etiology. Their preoperative examination maintain included: best corrected visual acuity (BCVA), thorough anterior segment examination, by slit -lamp especially for the degree and extent of subluxation and cataract, cornea, iris and the pupil for other abnormalities or other traumatic signs, presence or absence of vitreous in the anterior chamber, IOP and finally fundus examination. The patients were then divided into 3 groups each comprising 6 patients. The first group underwent ECCE with sulcus implantation PMMA IOL , the second and third groups underwent phacoemulsification with bag implanted Acrylic IOL but the third group underwent special techniques and precautions during surgery. Postoperatively, all patients were examined for BCVA, IOP, IOL positioning, pupil, fundus examination. Thirteen patients were males and five were females. The etiology of subluxation was traumatic in ten males and two female. The ages of the patients were between 11 and 62 years old the post operative follow up period ranged between 7 and 16 months. No major intraoperative complications were noted. In the 1st group 2 patients underwent AC automated vitrectomy, 3 in the 2nd group, 1 in the 3rd group. Three patients needed scleral fixation suture . Thirteen patients had well centered IOL and 4 had slight decentration not necessitating further intervention and one in the 2nd group had clinically significant decentration where IOL explanation, widening of the wound and re implantation of a wide 6.5mm optic PMMA IOL was done in the second post operative daily. Subluxated cataracts need special precautions in the chosen surgical technique to maintain a reasonable safety level intraoperatively and an acceptable surgical.

  1. Pylorus-preserving Whipple pancreaticoduodenectomy: Postoperative evaluation of a new surgical technique

    International Nuclear Information System (INIS)

    Trerotola, S.O.; Jones, B.; Crist, D.J.; Cameron, J.L.

    1988-01-01

    The pylorus-preserving Whipple pancreaticoduodenectomy is becoming an increasingly popular alternative to the standard Whipple operation in the surgical treatment of diseases of the periampullary region. Contrast radiography plays an important role in the postoperative evaluation of patients undergoing this operation. Although most radiologists are familiar with the postoperative anatomy and complications associated with the standard Whipple operation, the newer technique involves different postoperative anatomy and different complications and requires a different approach to examination. The procedure presents several new diagnostic pitfalls. These variables are presented from a described series of 50 patients undergoing this procedure for periampullary neoplasm or chronic pancreatitis

  2. Anomalous Systemic Artery to the Left Lower Lobe: Literature Review and a New Surgical Technique.

    Science.gov (United States)

    Miller, Jacob R; Lancaster, Timothy S; Abarbanell, Aaron M; Manning, Peter B; Eghtesady, Pirooz

    2018-05-01

    Anomalous systemic arterial supply to the basal segments of the left lower lobe without coexisting pulmonary artery connection is a rare anomaly. Most feel treatment is necessary; however, the ideal strategy is unclear. Treatments described include embolization, pulmonary resection, or anastomosis to the native pulmonary artery. We recently encountered an infant with this anomaly and present a literature review summarizing all recent reports. Additionally, we describe a novel surgical technique to create a tension-free anastomosis utilizing segmental aortic translocation that we employed in our patient due to a large distance between the anomalous vessel and native left pulmonary artery.

  3. Suture fixation of migrated septal occluder device to prevent further migration: a simple surgical technique

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    Mohite Prashant N

    2013-01-01

    Full Text Available Abstract As the use of percutaneous intervention is increasing for the closure of the atrial septal defect, the procedure related complications are also on rise, migration of the device being most common. The migrated devices with failed percutaneous retrieval must be removed surgically under cardiopulmonary bypass. During establishment of cardiopulmonary bypass, the handling of heart may cause further migration of the device into other chambers of heart which leads to difficulty in finding and retrieval of the device. The authors propose a simple and unique technique to prevent further migration of the septal occluder device.

  4. A Case of Microstomia Subsequent to Toxic Epidermal Necrolysis Surgically Treated by Simple Technique

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    Takanobu Mashiko, MD

    2013-06-01

    Full Text Available Summary: Toxic epidermal necrolysis (TEN is a rare but severe adverse dermatitis that is an autoimmune reaction to drugs such as nonsteroidal anti-inflammatory drugs. TEN most severely affects the mucous membranes including the mouth and could develop into microstomia; however, microstomia in relation to TEN has rarely been reported in the literature. We describe an adult female patient who developed microstomia due to scar contracture of the bilateral oral commissures subsequent to TEN and was successfully treated by a simple surgical technique consisting solely of transverse incision of the commissure and longitudinal closure.

  5. Skull reconstruction after resection of bone tumors in a single surgical time by the association of the techniques of rapid prototyping and surgical navigation.

    Science.gov (United States)

    Anchieta, M V M; Salles, F A; Cassaro, B D; Quaresma, M M; Santos, B F O

    2016-10-01

    Presentation of a new cranioplasty technique employing a combination of two technologies: rapid prototyping and surgical navigation. This technique allows the reconstruction of the skull cap after the resection of a bone tumor in a single surgical time. The neurosurgeon plans the craniotomy previously on the EximiusMed software, compatible with the Eximius Surgical Navigator, both from the company Artis Tecnologia (Brazil). The navigator imports the planning and guides the surgeon during the craniotomy. The simulation of the bone fault allows the virtual reconstruction of the skull cap and the production of a personalized modelling mold using the Magics-Materialise (Belgium)-software. The mold and a replica of the bone fault are made by rapid prototyping by the company Artis Tecnologia (Brazil) and shipped under sterile conditions to the surgical center. The PMMA prosthesis is produced during the surgical act with the help of a hand press. The total time necessary for the planning and production of the modelling mold is four days. The precision of the mold is submillimetric and accurately reproduces the virtual reconstruction of the prosthesis. The production of the prosthesis during surgery takes until twenty minutes depending on the type of PMMA used. The modelling mold avoids contraction and dissipates the heat generated by the material's exothermic reaction in the polymerization phase. The craniectomy is performed with precision over the drawing made with the help of the Eximius Surgical Navigator, according to the planned measurements. The replica of the bone fault serves to evaluate the adaptation of the prosthesis as a support for the perforations and the placement of screws and fixation plates, as per the surgeon's discretion. This technique allows the adequate oncologic treatment associated with a satisfactory aesthetic result, with precision, in a single surgical time, reducing time and costs.

  6. Study of the standard direct costs of various techniques of advanced endoscopy. Comparison with surgical alternatives.

    Science.gov (United States)

    Loras, Carme; Mayor, Vicenç; Fernández-Bañares, Fernando; Esteve, Maria

    2018-03-12

    The complexity of endoscopy has carried out an increase in cost that has a direct effect on the healthcare systems. However, few studies have analyzed the cost of advanced endoscopic procedures (AEP). To carry out a calculation of the standard direct costs of AEP, and to make a financial comparison with their surgical alternatives. Calculation of the standard direct cost in carrying out each procedure. An endoscopist detailed the time, personnel, materials, consumables, recovery room time, stents, pathology and medication used. The cost of surgical procedures was the average cost recorded in the hospital. Thirty-eight AEP were analyzed. The technique showing lowest cost was gastroscopy + APC (€116.57), while that with greatest cost was ERCP with cholangioscopy + stent placement (€5083.65). Some 34.2% of the procedures registered average costs of €1000-2000. In 57% of cases, the endoscopic alternative was 2-5 times more cost-efficient than surgery, in 31% of cases indistinguishable or up to 1.4 times more costly. Standard direct cost of the majority of AEP is reported using a methodology that enables easy application in other centers. For the most part, endoscopic procedures are more cost-efficient than the corresponding surgical procedure. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. "A tree must be bent while it is young": teaching urological surgical techniques to schoolchildren.

    Science.gov (United States)

    Buntrock, Stefan

    2012-01-01

    Playing video games in childhood may help achieve advanced laparoscopic skills later in life. The virtual operating room will soon become a reality, as "doctor games 2.0" will doubtlessly begin to incorporate virtual laparoscopic techniques. To teach surgical skills to schoolchildren in order to attract them to urology as a professional choice later in life. As part of EAU Urology Week 2010, 108 school children aged 15-19 attended a seminar with lectures and simulators (laparoscopy, TUR, cystoscopy, and suture sets) at the 62nd Congress of the German Society of Urology in Düsseldorf. A Pub-Med and Google Scholar search was also performed in order to review the beneficial effects of early virtual surgical training. MeSh terms used were "video games," "children," and "surgical skills." Searches were performed without restriction for a certain period of time. In terms of publicity for urology, EAU Urology Week, and the German Society of Urology, the event was immensely successful. Regarding the literature search, four relevant publications were found involving children. An additional three articles evaluated the usefulness of video gaming in medical students and residents. Making use of virtual reality to attract and educate a new generation of urologists is an important step in designing the future of urology.

  8. Photon attenuation correction technique in SPECT based on nonlinear optimization

    International Nuclear Information System (INIS)

    Suzuki, Shigehito; Wakabayashi, Misato; Okuyama, Keiichi; Kuwamura, Susumu

    1998-01-01

    Photon attenuation correction in SPECT was made using a nonlinear optimization theory, in which an optimum image is searched so that the sum of square errors between observed and reprojected projection data is minimized. This correction technique consists of optimization and step-width algorithms, which determine at each iteration a pixel-by-pixel directional value of search and its step-width, respectively. We used the conjugate gradient and quasi-Newton methods as the optimization algorithm, and Curry rule and the quadratic function method as the step-width algorithm. Statistical fluctuations in the corrected image due to statistical noise in the emission projection data grew as the iteration increased, depending on the combination of optimization and step-width algorithms. To suppress them, smoothing for directional values was introduced. Computer experiments and clinical applications showed a pronounced reduction in statistical fluctuations of the corrected image for all combinations. Combinations using the conjugate gradient method were superior in noise characteristic and computation time. The use of that method with the quadratic function method was optimum if noise property was regarded as important. (author)

  9. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis.

    Science.gov (United States)

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-04-25

    Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM) techniques can further prevent the occurrence of false positives with conventional MRI, distinguish which are clinically relevant from levels of cauda equina and/or nerve root lesions based on MRI, and determine and reduce the decompression levels of lumbar spinal stenosis than MRI + NE, while ensuring or improving surgical outcomes. We compared the data between patients who underwent MRI + (PM or DTI) and patients who underwent conventional MRI + NE to determine levels of decompression for the treatment of lumbar spinal stenosis. Outcome measures were assessed at 2 weeks, 3 months, 6 months, and 12 months postoperatively. One hundred fourteen patients (59 in the control group, 54 in the experimental group) underwent decompression. The levels of decompression determined by MRI + (PM or DTI) in the experimental group were significantly less than that determined by MRI + NE in the control group (p = 0.000). The surgical time, blood loss, and surgical transfusion were significantly less in the experimental group (p = 0.001, p = 0.011, p = 0.001, respectively). There were no differences in improvement of the visual analog scale back and leg pain (VAS-BP, VAS-LP) scores and Oswestry Disability Index (ODI) scores at 2 weeks, 3 months, 6 months, and 12 months after operation between the experimental and control groups. MRI + (PM or DTI) showed clear benefits in determining decompression levels of lumbar spinal stenosis than MRI + NE. In patients with lumbar spinal

  10. Reliability analysis of large scaled structures by optimization technique

    International Nuclear Information System (INIS)

    Ishikawa, N.; Mihara, T.; Iizuka, M.

    1987-01-01

    This paper presents a reliability analysis based on the optimization technique using PNET (Probabilistic Network Evaluation Technique) method for the highly redundant structures having a large number of collapse modes. This approach makes the best use of the merit of the optimization technique in which the idea of PNET method is used. The analytical process involves the minimization of safety index of the representative mode, subjected to satisfaction of the mechanism condition and of the positive external work. The procedure entails the sequential performance of a series of the NLP (Nonlinear Programming) problems, where the correlation condition as the idea of PNET method pertaining to the representative mode is taken as an additional constraint to the next analysis. Upon succeeding iterations, the final analysis is achieved when a collapse probability at the subsequent mode is extremely less than the value at the 1st mode. The approximate collapse probability of the structure is defined as the sum of the collapse probabilities of the representative modes classified by the extent of correlation. Then, in order to confirm the validity of the proposed method, the conventional Monte Carlo simulation is also revised by using the collapse load analysis. Finally, two fairly large structures were analyzed to illustrate the scope and application of the approach. (orig./HP)

  11. Optimization Techniques for 3D Graphics Deployment on Mobile Devices

    Science.gov (United States)

    Koskela, Timo; Vatjus-Anttila, Jarkko

    2015-03-01

    3D Internet technologies are becoming essential enablers in many application areas including games, education, collaboration, navigation and social networking. The use of 3D Internet applications with mobile devices provides location-independent access and richer use context, but also performance issues. Therefore, one of the important challenges facing 3D Internet applications is the deployment of 3D graphics on mobile devices. In this article, we present an extensive survey on optimization techniques for 3D graphics deployment on mobile devices and qualitatively analyze the applicability of each technique from the standpoints of visual quality, performance and energy consumption. The analysis focuses on optimization techniques related to data-driven 3D graphics deployment, because it supports off-line use, multi-user interaction, user-created 3D graphics and creation of arbitrary 3D graphics. The outcome of the analysis facilitates the development and deployment of 3D Internet applications on mobile devices and provides guidelines for future research.

  12. Detour technique, Dipping technique, or IIeal bladder flap technique for surgical correction of uretero-ileal anastomotic stricture in orthotopic ileal neobladder

    Directory of Open Access Journals (Sweden)

    Mohamed Wishahi

    2015-08-01

    Full Text Available ABSTRACTBackground:Uretero-ileal anastomotic stricture (UIAS is a urological complication after ileal neobladder, the initial management being endourological intervention. If this fails or stricture recurs, surgical intervention will be indicated.Design and Participants:From 1994 to 2013, 129 patients were treated for UIAS after unsuccessful endourological intervention. Unilateral UIAS was present in 101 patients, and bilateral in 28 patients; total procedures were 157. The previous ileal neobladder techniques were Hautmann neobladder, detubularized U shape, or spherical shape neobladder.Surgical procedures:Dipping technique was performed in 74 UIAS. Detour technique was done in 60 renal units. Ileal Bladder flap was indicated in 23 renal units. Each procedure ended with insertion of double J, abdominal drain, and indwelling catheter.Results:Follow-up was done for 12 to 36 months. Patency of the anastomosis was found in 91.7 % of cases. Thirteen patients (8.3% underwent antegrade dilatation and insertion of double J.Conclusion:After endourological treatment for uretero-ileal anastomotic failure, basically three techniques may be indicated: dipping technique, detour technique, and ileal bladder flap. The indications are dependent on the length of the stenotic/dilated ureteral segment. Better results for long length of stenotic ureter are obtained with detour technique; for short length stenotic ureter dipping technique; when the stenotic segment is 5 cm or more with a short ureter, the ileal tube flap is indicated. The use of double J stent is mandatory in the majority of cases. Early intervention is the rule for protecting renal units from progressive loss of function.

  13. Greenhouse Environmental Control Using Optimized MIMO PID Technique

    Directory of Open Access Journals (Sweden)

    Fateh BOUNAAMA

    2011-10-01

    Full Text Available Climate control for protected crops brings the added dimension of a biological system into a physical system control situation. The thermally dynamic nature of a greenhouse suggests that disturbance attenuation (load control of external temperature, humidity, and sunlight is far more important than is the case for controlling other types of buildings. This paper investigates the application of multi-inputs multi-outputs (MIMO PID controller to a MIMO greenhouse environmental model with actuation constraints. This method is based on decoupling the system at low frequency point. The optimal tuning values are determined using genetic algorithms optimization (GA. The inside outsides climate model of the environmental greenhouse, and the automatically collected data sets of Avignon, France are used to simulate and test this technique. The control objective is to maintain a highly coupled inside air temperature and relative humidity of strongly perturbed greenhouse, at specified set-points, by the ventilation/cooling and moisturizing operations.

  14. Virtual Surgical Planning for Correction of Delayed Presentation Scaphocephaly Using a Modified Melbourne Technique.

    Science.gov (United States)

    Macmillan, Alexandra; Lopez, Joseph; Mundinger, Gerhard S; Major, Melanie; Medina, Miguel A; Dorafshar, Amir H

    2018-02-23

    Late treatment of scaphocephaly presents challenges including need for more complex surgery to achieve desired head shape. Virtual surgical planning for total vault reconstruction may mitigate some of these challenges, but has not been studied in this unique and complex clinical setting. A retrospective chart review was conducted for patients with scaphocephaly who presented to our institution between 2000 and 2014. Patients presenting aged 12 months or older who underwent virtual surgical planning-assisted cranial vault reconstruction were included. Patient demographic, intraoperative data, and postoperative outcomes were recorded. Pre- and postoperative anthropometric measurements were obtained to document the fronto-occipital (FO) and biparietal (BP) distance and calculate cephalic index (CI). Virtual surgical planning predicted, and actual postoperative anthropometric measurements were compared. Five patients were identified who fulfilled inclusion criteria. The mean age was 50.6 months. One patient demonstrated signs of elevated intracranial pressure preoperatively. Postoperatively, all but one needed no revisional surgery (Whitaker score of 1). No patient demonstrated postoperative evidence of bony defects, bossing, or suture restenosis. The mean preoperative, simulated, and actual postoperative FO length was 190.3, 182, and 184.3 mm, respectively. The mean preoperative, simulated, and actual postoperative BP length was 129, 130.7, and 131 mm, respectively. The mean preoperative, simulated, and actual postoperative CI was 66, 72, and 71.3, respectively. Based on our early experience, virtual surgical planning using a modified Melbourne technique for total vault remodeling achieves good results in the management of late presenting scaphocephaly.

  15. Satisfactory patient-based outcomes after surgical treatment for idiopathic clubfoot: includes surgeon's individualized technique.

    Science.gov (United States)

    Mahan, Susan T; Spencer, Samantha A; Kasser, James R

    2014-09-01

    Treatment of idiopathic clubfoot has shifted towards Ponseti technique, but previously surgical management was standard. Outcomes of surgery have varied, with many authors reporting discouraging results. Our purpose was to evaluate a single surgeon's series of children with idiopathic clubfoot treated with a la carte posteromedial and lateral releases using the Pediatric Outcomes Data Collection Instrument (PODCI) with a minimum of 2-year follow-up. A total of 148 patients with idiopathic clubfoot treated surgically by a single surgeon over 15 years were identified, and mailed PODCI questionnaires. Fifty percent of the patients were located and responded, resulting in 74 complete questionnaires. Median age at surgery was 10 months (range, 5.3 to 84.7 mo), male sex 53/74 (71.6%), bilateral surgery 31/74 (41.9%), and average follow-up of 9.7 years. PODCI responses were compared with previously published normal healthy controls using t test for each separate category. Included in the methods is the individual surgeon's operative technique. In PODCIs where a parent reports for their child or adolescent, there was no difference between our data and the healthy controls in any of the 5 categories. In PODCI where an adolescent self-reports, there was no difference in 4 of 5 categories; significant difference was only found between our data (mean = 95.2; SD = 7.427) and normal controls (mean = 86.3; SD = 12.5) in Happiness Scale (P = 0.0031). In this group of idiopathic clubfoot patients, treated with judicious posteromedial release by a single surgeon, primarily when surgery was treatment of choice for clubfoot, patient-based outcomes are not different from their normal healthy peers through childhood and adolescence. While Ponseti treatment has since become the treatment of choice for clubfoot, surgical treatment, in some hands, has led to satisfactory results. Level III.

  16. Planned posterior assisted levitation in severe subluxated cataract: Surgical technique and clinical results

    Directory of Open Access Journals (Sweden)

    Tova Lifshitz

    2012-01-01

    Full Text Available We report the surgical technique and outcome of planned posterior assisted levitation (P-PAL in four cases of subluxated cataract. P-PAL was planned as the preferred approach in all cases. A spatula was inserted via the pars plana, the whole lens was lifted to the anterior chamber and then removed through a scleral tunnel incision. Anterior chamber intraocular lenses were implanted in all cases. All four eyes had severe subluxation of the crystalline lenses with marked phacodonesis. Two eyes had history of blunt trauma, and the other two eyes had severe pseudoexfoliation with spontaneous lens subluxation. Follow-up ranged from 1 to 2 years in three cases. The postoperative visual acuity was 20/80 or better. No intraoperative complications were observed. In conclusion, the P-PAL technique was successfully performed during cataract surgery in four eyes with severe subluxated cataracts. There were no complications over the long-term follow-up.

  17. [Endonasal versus trans-canalicular endoscopic dacriocystorhinostomy using diode laser. Surgical techniques and outcomes].

    Science.gov (United States)

    Piédrola Maroto, David; Franco Sánchez, Javier; Reyes Eldblom, Robin; Monje Vega, Elena; Conde Jiménez, Manuel; Ortiz Rueda, Manuel

    2008-01-01

    To evaluate the benefits and disadvantages of the endoscopic endonasal versus transcanalicular approaches using diode laser, and to compare their clinical outcomes. A total of 127 patients were operated on, 80 of them with the endonasal approach (Group I) and 47 with the transcanalicular technique (Group II). Epiphora improved completely in 67 patients in Group I (83.7 %) while the other 13 (16.2 %) continued to present the same symptoms. In Group II, a successful result was achieved in 39 patients (82.9 %) and 8 (17 %) of them had to be re-operated because of the persistence of epiphora. The surgical outcomes are similar with both laser techniques. The main advantages of using diode laser are that it does not require general anaesthesia, the lower intra- and peri-operative morbidity, the lack of nasal packing and the greater ease of performing additional interventions if it fails. The only real disadvantage of laser procedures is the high cost.

  18. Utilization of two different surgical techniques in gingival recession treatment: A comparative study

    Directory of Open Access Journals (Sweden)

    Bajić Miljan

    2014-01-01

    Full Text Available Introduction. Gingival recession is a displacement of gingival margin apically to cementenamel junction. Objective. The aim of this study was to compare the results achieved with two different surgical procedures used in gingival recession treatment. Methods. Ten patients with bilateral buccal recession on maxillary canines or premolars were included in the study. Professional teeth cleaning was performed before surgery. Recession on the experimental side was treated with connective tissue graft in combination with coronally advanced, split thickness flap (tunnel technique. Control side recession was treated with connective tissue graft in combination with trapezoidal coronally advanced, full thickness flap. Coin toss was used for side decision. The following parameters were evaluated before surgery and 6 months post-op: Vertical Recession Dimension, Clinical Attachment Level, Apico-coronal width of the keratinized tissue, Healing index (Laundry, RES index, and Patient evaluation of esthetic results. Student’s t-test was used for statistical analysis. Results. Six months after surgery, mean root coverage was 91.5±14.1% and 90.1±14.6% on the experimental and on the control side, respectively. RES index, Healing index (Laundry and Patient Subjective evaluation of esthetic results showed significantly better results (p≤0.05. Conclusion. Both surgical procedures produce highly successful clinical results based on evaluated parameters, but this tunnel technique provides significantly better esthetic results. [Projekat Ministarstva nauke Republike Srbije, br. III 41008: Interakcija etiopatogenetskih mehanizama parodontopatije i periimplantitisa sa sistemskim bolestima današnjice

  19. Multivariate Analysis Techniques for Optimal Vision System Design

    DEFF Research Database (Denmark)

    Sharifzadeh, Sara

    The present thesis considers optimization of the spectral vision systems used for quality inspection of food items. The relationship between food quality, vision based techniques and spectral signature are described. The vision instruments for food analysis as well as datasets of the food items...... used in this thesis are described. The methodological strategies are outlined including sparse regression and pre-processing based on feature selection and extraction methods, supervised versus unsupervised analysis and linear versus non-linear approaches. One supervised feature selection algorithm...... (SSPCA) and DCT based characterization of the spectral diffused reflectance images for wavelength selection and discrimination. These methods together with some other state-of-the-art statistical and mathematical analysis techniques are applied on datasets of different food items; meat, diaries, fruits...

  20. Optimization of AFP-radioimmunoassay using Antibody Capture Technique

    International Nuclear Information System (INIS)

    Moustafa, K.A.

    2003-01-01

    Alpha-fetoprotein (AFP) is a substance produced by the unborn baby. When the neural tube is not properly formed large amounts of AFP pass into the amniotic fluid and reach the mother's blood. By measuring AFP in the mother's blood and amniotic fluid, it is possible to tell whether or not there is a chance that the unborn baby has a neural tube defect. AFP also used as a tumor marker for hepatocellular carcinoma. There are many different techniques for measuring AFP in blood, but the most accurate one is the immunoassay technique. The immunoassays can be classified on the basis of methodology into three classes; (1) the antibody capture assays, (2) the antigen capture assay, (3)the two-antibody sandwich assays. In this present study, the antibody capture assay in which the antigen is attached to a solid support, and labeled antibody is allowed to bind, will be optimized

  1. Surgical Techniques for Diaphragmatic Resection During Cytoreduction in Advanced or Recurrent Ovarian Carcinoma: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Bogani, Giorgio; Ditto, Antonino; Martinelli, Fabio; Lorusso, Domenica; Chiappa, Valentina; Donfrancesco, Cristina; Di Donato, Violante; Indini, Alice; Aletti, Giovanni; Raspagliesi, Francesco

    2016-02-01

    Optimal cytoreduction is one the main factors improving survival outcomes in patients affected by ovarian cancer (OC). It is estimated that approximately 40% of OC patients have gross disease located on the diaphragm. However, no mature data evaluating outcomes of surgical techniques for the management of diaphragmatic carcinosis exist. In the present study, we aimed to estimate surgery-related morbidity of different surgical techniques for diaphragmatic cytoreduction in advanced or recurrent OC. PubMed (MEDLINE), Web of Science, and Clincaltrials.gov databases were searched for records estimating outcomes of diaphragmatic peritoneal stripping (DPS) or diaphragmatic full-thickness resection (DFTR) for OC. The meta-analysis was performed using the Cochrane Review software. For the final analysis, 5 articles were available, including 272 patients. Diaphragmatic peritoneal stripping and DFTR were performed in 197 patients (72%) and 75 patients (28%), respectively. Pooled analysis suggested that the estimated pleural effusion rate was 43% and 51% after DPS and DFTR, respectively. The need for pleural punctures or chest tube placement was 4% and 9% after DPS and DFTR, respectively. The rate of postoperative pneumothorax (4% vs 9%; odds ratio, 0.31; 95% confidence interval, 0.05-2.08) and subdiaphragmatic abscess (3% vs 3%; odds ratio, 0.45; 95% confidence interval, 0.09-2.31) were similar after the execution of DPS and DFTR. Diaphragmatic surgery is a crucial step during cytoreduction for advanced or recurrent OC. Obviously, the choice to perform DPS or DFTR depends on the infiltration of the diaphragmatic muscle or not. Both the procedures are associated with a low pulmonary complication and chest tube placement rates.

  2. Optimization of analytical techniques to characterize antibiotics in aquatic systems

    International Nuclear Information System (INIS)

    Al Mokh, S.

    2013-01-01

    Antibiotics are considered as pollutants when they are present in aquatic ecosystems, ultimate receptacles of anthropogenic substances. These compounds are studied as their persistence in the environment or their effects on natural organisms. Numerous efforts have been made worldwide to assess the environmental quality of different water resources for the survival of aquatic species, but also for human consumption and health risk related. Towards goal, the optimization of analytical techniques for these compounds in aquatic systems remains a necessity. Our objective is to develop extraction and detection methods for 12 molecules of aminoglycosides and colistin in sewage treatment plants and hospitals waters. The lack of analytical methods for analysis of these compounds and the deficiency of studies for their detection in water is the reason for their study. Solid Phase Extraction (SPE) in classic mode (offline) or online followed by Liquid Chromatography analysis coupled with Mass Spectrometry (LC/MS/MS) is the most method commonly used for this type of analysis. The parameters are optimized and validated to ensure the best conditions for the environmental analysis. This technique was applied to real samples of wastewater treatment plants in Bordeaux and Lebanon. (author)

  3. An entropy flow optimization technique for helium liquefaction cycles

    International Nuclear Information System (INIS)

    Minta, M.; Smith, J.L.

    1984-01-01

    This chapter proposes a new method of analyzing thermodynamic cycles based on a continuous distribution of precooling over the temperature range of the cycle. The method gives the optimum distribution of precooling over the temperature range of the cycle by specifying the mass flow to be expanded at each temperature. The result is used to select a cycle configuration with discrete expansions and to initialize the independent variables for final optimization. Topics considered include the continuous precooling model, the results for ideal gas, the results for real gas, and the application to the design of a saturated vapor compression (SVC) cycle. The optimization technique for helium liquefaction cycles starts with the minimization of the generated entropy in a cycle model with continuous precooling. The pressure ratio, the pressure level and the distribution of the heat exchange are selected based on the results of the continuous precooling analysis. It is concluded that the technique incorporates the non-ideal behavior of helium in the procedure and allows the trade-off between heat exchange area and losses to be determined

  4. Using simulation-optimization techniques to improve multiphase aquifer remediation

    Energy Technology Data Exchange (ETDEWEB)

    Finsterle, S.; Pruess, K. [Lawrence Berkeley Laboratory, Berkeley, CA (United States)

    1995-03-01

    The T2VOC computer model for simulating the transport of organic chemical contaminants in non-isothermal multiphase systems has been coupled to the ITOUGH2 code which solves parameter optimization problems. This allows one to use linear programming and simulated annealing techniques to solve groundwater management problems, i.e. the optimization of operations for multiphase aquifer remediation. A cost function has to be defined, containing the actual and hypothetical expenses of a cleanup operation which depend - directly or indirectly - on the state variables calculated by T2VOC. Subsequently, the code iteratively determines a remediation strategy (e.g. pumping schedule) which minimizes, for instance, pumping and energy costs, the time for cleanup, and residual contamination. We discuss an illustrative sample problem to discuss potential applications of the code. The study shows that the techniques developed for estimating model parameters can be successfully applied to the solution of remediation management problems. The resulting optimum pumping scheme depends, however, on the formulation of the remediation goals and the relative weighting between individual terms of the cost function.

  5. Optimized evaporation technique for leachate treatment: Small scale implementation.

    Science.gov (United States)

    Benyoucef, Fatima; Makan, Abdelhadi; El Ghmari, Abderrahman; Ouatmane, Aziz

    2016-04-01

    This paper introduces an optimized evaporation technique for leachate treatment. For this purpose and in order to study the feasibility and measure the effectiveness of the forced evaporation, three cuboidal steel tubs were designed and implemented. The first control-tub was installed at the ground level to monitor natural evaporation. Similarly, the second and the third tub, models under investigation, were installed respectively at the ground level (equipped-tub 1) and out of the ground level (equipped-tub 2), and provided with special equipment to accelerate the evaporation process. The obtained results showed that the evaporation rate at the equipped-tubs was much accelerated with respect to the control-tub. It was accelerated five times in the winter period, where the evaporation rate was increased from a value of 0.37 mm/day to reach a value of 1.50 mm/day. In the summer period, the evaporation rate was accelerated more than three times and it increased from a value of 3.06 mm/day to reach a value of 10.25 mm/day. Overall, the optimized evaporation technique can be applied effectively either under electric or solar energy supply, and will accelerate the evaporation rate from three to five times whatever the season temperature. Copyright © 2016. Published by Elsevier Ltd.

  6. Towards Clinically Optimized MRI-guided Surgical Manipulator for Minimally Invasive Prostate Percutaneous Interventions: Constructive Design*

    Science.gov (United States)

    Eslami, Sohrab; Fischer, Gregory S.; Song, Sang-Eun; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M.; Iordachita, Iulian

    2013-01-01

    This paper undertakes the modular design and development of a minimally invasive surgical manipulator for MRI-guided transperineal prostate interventions. Severe constraints for the MRI-compatibility to hold the minimum artifact on the image quality and dimensions restraint of the bore scanner shadow the design procedure. Regarding the constructive design, the manipulator kinematics has been optimized and the effective analytical needle workspace is developed and followed by proposing the workflow for the manual needle insertion. A study of the finite element analysis is established and utilized to improve the mechanism weaknesses under some inevitable external forces to ensure the minimum structure deformation. The procedure for attaching a sterile plastic drape on the robot manipulator is discussed. The introduced robotic manipulator herein is aimed for the clinically prostate biopsy and brachytherapy applications. PMID:24683502

  7. Surgical techniques for the treatment of carpal ligament injury in the athlete.

    Science.gov (United States)

    Paci, Gabrielle M; Yao, Jeffrey

    2015-01-01

    Treatment of intercarpal ligament injuries in the athlete requires special attention due to several practical and biomechanical considerations. Optimally, the athlete will maintain as much function and range of motion as possible with return to high-impact and load-bearing activity in a timely fashion. Several cutting-edge techniques have arisen in treatment. This article discusses injury patterns in the athlete with scapholunate injury, lunotriquetral injury, scaphotrapezial-trapezoidal injury, and extrinsic ligamentous injury, and the various approaches to addressing these injuries, with a review of the classic as well as newer, innovative techniques. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Direct surgical repair of spondylolysis in athletes: indications, techniques, and outcomes.

    Science.gov (United States)

    Drazin, Doniel; Shirzadi, Ali; Jeswani, Sunil; Ching, Harry; Rosner, Jack; Rasouli, Alexandre; Kim, Terrence; Pashman, Robert; Johnson, J Patrick

    2011-11-01

    Athletes present with back pain as a common symptom. Various sports involve repetitive hyperextension of the spine along with axial loading and appear to predispose athletes to the spinal pathology spondylolysis. Many athletes with acute back pain require nonsurgical treatment methods; however, persistent recurrent back pain may indicate degenerative disc disease or spondylolysis. Young athletes have a greater incidence of spondylolysis. Surgical solutions are many, and yet there are relatively few data in the literature on both the techniques and outcomes of spondylolytic repair in athletes. In this study, the authors undertook a review of the surgical techniques and outcomes in the treatment of symptomatic spondylolysis in athletes. A systematic review of the MEDLINE and PubMed databases was performed using the following key words to identify articles published between 1950 and 2011: "spondylolysis," "pars fracture," "repair," "athlete," and/or "sport." Papers on both athletes and nonathletes were included in the review. Articles were read for data on methodology (retrospective vs prospective), type of treatment, number of patients, mean patient age, and mean follow-up. Eighteen articles were included in the review. Eighty-four athletes and 279 nonathletes with a mean age of 20 and 21 years, respectively, composed the population under review. Most of the fractures occurred at L-5 in both patient groups, specifically 96% and 92%, respectively. The average follow-up period was 26 months for athletes and 86 months for nonathletes. According to the modified Henderson criteria, 84% (71 of 84) of the athletes returned to their sports activities. The time intervals until their return ranged from 5 to 12 months. For a young athlete with a symptomatic pars defect, any of the described techniques of repair would probably produce acceptable results. An appropriate preoperative workup is important. The ideal candidate is younger than 20 years with minimal or no listhesis and

  9. Repair-oriented classification of aortic insufficiency: impact on surgical techniques and clinical outcomes.

    Science.gov (United States)

    Boodhwani, Munir; de Kerchove, Laurent; Glineur, David; Poncelet, Alain; Rubay, Jean; Astarci, Parla; Verhelst, Robert; Noirhomme, Philippe; El Khoury, Gébrine

    2009-02-01

    Valve repair for aortic insufficiency requires a tailored surgical approach determined by the leaflet and aortic disease. Over the past decade, we have developed a functional classification of AI, which guides repair strategy and can predict outcome. In this study, we analyze our experience with a systematic approach to aortic valve repair. From 1996 to 2007, 264 patients underwent elective aortic valve repair for aortic insufficiency (mean age - 54 +/- 16 years; 79% male). AV was tricuspid in 171 patients bicuspid in 90 and quadricuspid in 3. One hundred fifty three patients had type I dysfunction (aortic dilatation), 134 had type II (cusp prolapse), and 40 had type III (restrictive). Thirty six percent (96/264) of the patients had more than one identified mechanism. In-hospital mortality was 1.1% (3/264). Six patients experienced early repair failure; 3 underwent re-repair. Functional classification predicted the necessary repair techniques in 82-100% of patients, with adjunctive techniques being employed in up to 35% of patients. Mid-term follow up (median [interquartile range]: 47 [29-73] months) revealed a late mortality rate of 4.2% (11/261, 10 cardiac). Five year overall survival was 95 +/- 3%. Ten patients underwent aortic valve reoperation (1 re-repair). Freedoms from recurrent Al (>2+) and from AV reoperation at 5 years was 88 +/- 3% and 92 +/- 4% respectively and patients with type I (82 +/- 9%; 93 +/- 5%) or II (95 +/- 5%; 94 +/- 6%) had better outcomes compared to type III (76 +/- 17%; 84 +/- 13%). Aortic valve repair is an acceptable therapeutic option for patients with aortic insufficiency. This functional classification allows a systematic approach to the repair of Al and can help to predict the surgical techniques required as well as the durability of repair. Restrictive cusp motion (type III), due to fibrosis or calcification, is an important predictor for recurrent Al following AV repair.

  10. A Unique Surgical Technique for Tracheostomy in Heterotopic Ossification: A Case Report.

    Science.gov (United States)

    Cheng, Esther; Thorpe, Eric

    2016-11-01

    To describe a technique for tracheostomy in heterotopic ossification that has not yet been described in the literature. We report a case of difficult tracheostomy while using conventional techniques in a 68-year-old patient who underwent mitral valve replacement requiring warfarin therapy three months prior. Imaging revealed heterotopic ossification overlying the trachea. A literature review was performed to identify similar cases or techniques. Extensive surgical planning was pursued after the initial attempted tracheostomy failed, and the airway was eventually accessed using a lighted intubation stylet for guidance and a drill. Heterotopic ossification has been described after orthopedic and abdominal surgeries. We identified one case report in the literature of tracheostomy performed in the setting of heterotopic ossification by an unspecified mechanism. There are few reported cases of tracheobronchial calcification in cardiac patients receiving warfarin therapy; however, these patients had characteristic imaging findings that were not consistent with those of our patient. We illustrate a safe and effective technique for tracheostomy in heterotopic ossification that has not been reported. Coordination with the anesthesia service was paramount for a successful operation. © The Author(s) 2016.

  11. Performance optimization in electro- discharge machining using a suitable multiresponse optimization technique

    Directory of Open Access Journals (Sweden)

    I. Nayak

    2017-06-01

    Full Text Available In the present research work, four different multi response optimization techniques, viz. multiple response signal-to-noise (MRSN ratio, weighted signal-to-noise (WSN ratio, Grey relational analysis (GRA and VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje in Serbian methods have been used to optimize the electro-discharge machining (EDM performance characteristics such as material removal rate (MRR, tool wear rate (TWR and surface roughness (SR simultaneously. Experiments have been planned on a D2 steel specimen based on L9 orthogonal array. Experimental results are analyzed using the standard procedure. The optimum level combinations of input process parameters such as voltage, current, pulse-on-time and pulse-off-time, and percentage contributions of each process parameter using ANOVA technique have been determined. Different correlations have been developed between the various input process parameters and output performance characteristics. Finally, the optimum performances of these four methods are compared and the results show that WSN ratio method is the best multiresponse optimization technique for this process. From the analysis, it is also found that the current has the maximum effect on the overall performance of EDM operation as compared to other process parameters.

  12. Current Techniques of Teaching and Learning in Bariatric Surgical Procedures: A Systematic Review.

    Science.gov (United States)

    Kaijser, Mirjam; van Ramshorst, Gabrielle; van Wagensveld, Bart; Pierie, Jean-Pierre

    The gastric sleeve resection and gastric bypass are the 2 most commonly performed bariatric procedures. This article provides an overview of current teaching and learning methods of those techniques in resident and fellow training. A database search was performed on Pubmed, Embase, and the Education Resources Information Center (ERIC) to identify the methods used to provide training in bariatric surgery worldwide. After exclusion based on titles and abstracts, full texts of the selected articles were assessed. Included articles were reviewed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. In total, 2442 titles were identified and 14 full text articles met inclusion criteria. Four publications described an ex vivo training course, and 6 focused on at least 1 step of the gastric bypass procedure. Two randomized controlled trials (RCT) provided high-quality evidence on training aspects. Surgical coaching caused significant improvement of Bariatric Objective Structured Assessment of Technical Skills (BOSATS) scores (3.60 vs. 3.90, p = 0.017) and reduction of technical errors (18 vs. 10, p = 0.003). A preoperative warm-up increased global rating scales (GRS) scores on depth perception (p = 0.02), bimanual dexterity (p = 0.01), and efficiency of movements (p = 0.03). Stepwise education, surgical coaching, warming up, Internet-based knowledge modules, and ex vivo training courses are effective in relation to bariatric surgical training of residents and fellows, possibly shortening their learning curves. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  13. Application of virtual reality techniques in preoperative surgical planning for intracranial anterior circulation aneurysms

    Directory of Open Access Journals (Sweden)

    Shou-sen WANG

    2012-05-01

    Full Text Available Objective  To investigate the value of virtual reality (VR technique in the surgical planning for anterior circulation aneurysms of Willis circle. Methods  A total of 50 patients with 57 aneurysms confirmed by CT angiography in the anterior circle of Willis were enrolled in this study. In preoperative Hunt-Hess scale, grade Ⅰ was designated in 7 patients, grade Ⅱ in 22, grade Ⅲ in 17, grade Ⅳ in 3, grade Ⅴ in 1 patient. Among the aneurysms, 16 were small (≤5mm in diameter, 28 medium (5-15mm, 10 large (15-25mm and 3 giant (≥25mm in size. The thin-slice head scanning data were achieved by 64-slice spiral CT machine. These data was then transferred into Dextroscope image workstation. The virtual imaging system generated clear and vivid virtual images. We compared the findings between simulation surgical operation and actual operation. Results  VR system make the operator felt "personally on the scene" and was able to communicate with the imaging. It could not only visually display the anatomical structures in three dimensions, but also could simulate some surgical procedures, which basically simulated the same outcome of actual operation. All the 50 patients were successfully treated by microsurgical clipping of main aneurysmal or contributory aneurysmal necks. Conclusions  The surgeons is able to be more confident, and the identification for the complex vascular abnormality is improved by planning operative procedure in virtual-reality environment. The virtual-reality system makes the actual operative procedure more concise, thus it is of positive value in surgery for intracranial aneurysm.

  14. Optimization of coronary optical coherence tomography imaging using the attenuation-compensated technique: a validation study.

    NARCIS (Netherlands)

    Teo, Jing Chun; Foin, Nicolas; Otsuka, Fumiyuki; Bulluck, Heerajnarain; Fam, Jiang Ming; Wong, Philip; Low, Fatt Hoe; Leo, Hwa Liang; Mari, Jean-Martial; Joner, Michael; Girard, Michael J A; Virmani, Renu; Bezerra, HG.; Costa, MA.; Guagliumi, G.; Rollins, AM.; Simon, D.; Gutiérrez-Chico, JL.; Alegría-Barrero, E.; Teijeiro-Mestre, R.; Chan, PH.; Tsujioka, H.; de Silva, R.; Otsuka, F.; Joner, M.; Prati, F.; Virmani, R.; Narula, J.; Members, WC.; Levine, GN.; Bates, ER.; Blankenship, JC.; Bailey, SR.; Bittl, JA.; Prati, F.; Guagliumi, G.; Mintz, G.S.; Costa, Marco; Regar, E.; Akasaka, T.; Roleder, T.; Jąkała, J.; Kałuża, GL.; Partyka, Ł.; Proniewska, K.; Pociask, E.; Girard, MJA.; Strouthidis, NG.; Ethier, CR.; Mari, JM.; Mari, JM.; Strouthidis, NG.; Park, SC.; Girard, MJA.; van der Lee, R.; Foin, N.; Otsuka, F.; Wong, P.K.; Mari, J-M.; Joner, M.; Nakano, M.; Vorpahl, M.; Otsuka, F.; Taniwaki, M.; Yazdani, SK.; Finn, AV.; Nakano, M.; Yahagi, K.; Yamamoto, H.; Taniwaki, M.; Otsuka, F.; Ladich, ER.; Girard, MJ.; Ang, M.; Chung, CW.; Farook, M.; Strouthidis, N.; Mehta, JS.; Foin, N.; Mari, JM.; Nijjer, S.; Sen, S.; Petraco, R.; Ghione, M.; Liu, X.; Kang, JU.; Virmani, R.; Kolodgie, F.D.; Burke, AP.; Farb, A.; Schwartz, S.M.; Yahagi, K.; Kolodgie, F.D.; Otsuka, F.; Finn, AV.; Davis, HR.; Joner, M.; Kume, T.; Akasaka, T.; Kawamoto, T.; Watanabe, N.; Toyota, E.; Neishi, Y.; Rieber, J.; Meissner, O.; Babaryka, G.; Reim, S.; Oswald, M.E.; Koenig, A.S.; Tearney, G. J.; Regar, E.; Akasaka, T.; Adriaenssens, T.; Barlis, P.; Bezerra, HG.; Yabushita, H.; Bouma, BE.; Houser, S. L.; Aretz, HT.; Jang, I-K.; Schlendorf, KH.; Guo, J.; Sun, L.; Chen, Y.D.; Tian, F.; Liu, HB.; Chen, L.; Kawasaki, M.; Bouma, BE.; Bressner, J. E.; Houser, S. L.; Nadkarni, S. K.; MacNeill, BD.; Jansen, CHP.; Onthank, DC.; Cuello, F.; Botnar, RM.; Wiethoff, AJ.; Warley, A.; von Birgelen, C.; Hartmann, A. M.; Kubo, T.; Akasaka, T.; Shite, J.; Suzuki, T.; Uemura, S.; Yu, B.; Habara, M.; Nasu, K.; Terashima, M.; Kaneda, H.; Yokota, D.; Ko, E.; Virmani, R.; Burke, AP.; Kolodgie, F.D.; Farb, A.; Takarada, S.; Imanishi, T.; Kubo, T.; Tanimoto, T.; Kitabata, H.; Nakamura, N.; Hattori, K.; Ozaki, Y.; Ismail, TF.; Okumura, M.; Naruse, H.; Kan, S.; Nishio, R.; Shinke, T.; Otake, H.; Nakagawa, M.; Nagoshi, R.; Inoue, T.; Sinclair, H.D.; Bourantas, C.; Bagnall, A.; Mintz, G.S.; Kunadian, V.; Tearney, G. J.; Yabushita, H.; Houser, S. L.; Aretz, HT.; Jang, I-K.; Schlendorf, KH.; van Soest, G.; Goderie, T.; Regar, E.; Koljenović, S.; Leenders, GL. van; Gonzalo, N.; Xu, C.; Schmitt, JM.; Carlier, SG.; Virmani, R.; van der Meer, FJ; Faber, D.J.; Sassoon, DMB.; Aalders, M.C.; Pasterkamp, G.; Leeuwen, TG. van; Schmitt, JM.; Knuttel, A.; Yadlowsky, M.; Eckhaus, MA.; Karamata, B.; Laubscher, M.; Leutenegger, M.; Bourquin, S.; Lasser, T.; Lambelet, P.; Vermeer, K.A.; Mo, J.; Weda, J.J.A.; Lemij, H.G.; Boer, JF. de

    2016-01-01

    PURPOSE To optimize conventional coronary optical coherence tomography (OCT) images using the attenuation-compensated technique to improve identification of plaques and the external elastic lamina (EEL) contour. METHOD The attenuation-compensated technique was optimized via manipulating contrast

  15. Esophagogastric pathology in morbid obese patient: preoperative diagnosis and influence in the selection of surgical technique

    Directory of Open Access Journals (Sweden)

    Sergio Estévez-Fernández

    2015-07-01

    Full Text Available Introduction: Given the difficulty in accessing to the excluded stomach after gastric bypass and the increase in gastroesophageal reflux after sleeve gastrectomy, it is justified to perform a preoperative fibrogastroscopy. The influence of the fibrogastroscopy (FGS findings in the therapeutic approach is analyzed. Patients and methods: A retrospective study of preoperative FGS findings is performed, from 04/06 to 12/12. The influence of the FGS results on the surgical technique selection, in the endoscopic or medical treatment and its relation to gastric fistula is analyzed by means of multivariate regression (confounding factors: Age, body mass index, arterial hypertension, diabetes mellitus, antiplatelet therapy, surgical technique (bariatric surgery, sleeve gastrectomy. Results: Three hundred thirty one patients are included: 32.6% biopsy of gastric lesion; 27% gastritis; 18.1% hiatal hernia; 3% metaplasia; 0.6% Barrett esophagus; 2.1% esophagitis; 0.3% dysplasia; 0.3 Schatzky's ring; 1.5% incompetent cardia; 2.4% duodenitis; 0.3% gastric erosions; 0.6% gastric xanthoma; 1.8%, gastric polyp; 1.6% duodenal ulcer; 0.6% papulo-erosive gastritis; 0.6% esophageal papilloma; 0.3% submucosal tumor. Helicobacter pylori+ 30.2% (triple therapy eradication in all patients. The FGS findings led to a variation in the surgical technique or to the completion of endoscopic treatment in 22.2% of cases. The gastric lesions did not influence the development of gastric fistula. Independent prognostic factors of fistula: Sleeve gastrectomy (7.9% vs. 2.7%; p = 0.02; OR: 1.38 IC95: 1.01-1.87 and the body mass index > 50 kg/m² (6.7% vs. 2.2%; p = 0.04; OR: 3.7 IC95: 1.12-12.4. Conclusions: The diagnosis of gastroesophageal disease through preoperative FGS motivated variations in the therapeutic approach in 52% of patients, so we consider essential to include the preoperative FGS in bariatric surgery.

  16. Achieving a predictable 24-hour return to normal activities after breast augmentation: part II. Patient preparation, refined surgical techniques, and instrumentation.

    Science.gov (United States)

    Tebbetts, John B

    2006-12-01

    The goal of this study was to develop practices that would allow patients undergoing subpectoral augmentation to predictably return to full normal activities within 24 hours after the operation, free of postoperative adjuncts. Part I of this study used motion and time study principles to reduce operative times, medication dosages, perioperative morbidity, and recovery times in augmentation mammaplasty. Part II of the study focuses on details of patient education, preoperative planning, instrumentation, and surgical technique modifications that were identified, modified, and implemented to achieve the results reported in part I. Two groups of 16 patients each (groups 1 and 2) were studied retrospectively for comparison to a third group of 627 patients (group 3) studied prospectively. Patients in group 1 had axillary partial retropectoral breast augmentations in 1982-1983, using dissociative anesthesia, blunt instrument implant pocket dissection, and Dow Corning, double-lumen implants containing 20 mg of methylprednisolone and 20 cc of saline in the outer lumen of the implants. Patients in group 2 (1990) had inframammary, retromammary augmentations by using a combination of blunt and electrocautery dissection, Surgitek Replicon polyurethane-covered, silicone gel-filled implants, and general endotracheal anesthesia. Patients in group 3 (1998 to 2001, n = 627) had inframammary partial retropectoral, inframammary retromammary, and axillary partial retropectoral augmentations under general endotracheal anesthesia. Refined practices and surgical techniques from studies of groups 1 and 2 were applied in group 3. Videotapes from operative procedures of groups 1 and 2 were analyzed with macromotion and micromotion study principles, and tables of events were formulated for each move during the operation for all personnel in the operating room. Extensive details of surgical technique were examined and reexamined in 13 different stages by using principles of motion and time

  17. The Comparison Between the Complications after Two Surgical Techniques of Esophageal Cancer

    Directory of Open Access Journals (Sweden)

    Mohamad Taghi Rajabi Mashhadi

    2014-08-01

    Full Text Available Introduction: Esophageal cancer is a common gastro intestinal malignancy. One of the most common techniques of surgery in esophageal cancer is transhiatal esophagectomy with esophagogastric anastomosis in the neck. This technique is accompanied by complications like chronic gastero-esophegeal reflux and late stenosis. This study was designed to compare the risk of complications after two surgical techniques for esophageal cancer: esophagogastric anastomosis with partial fundoplication and esophagogastric anastomosis without it. Materials and Methods: In this retrospective cohort study, 100 patients with distal two thirds of esophageal cancer who underwent transhiatal esophagectomy in Ghaem and Omid hospitals Mashhad University of Medical Sciences from 2005 to 2010 were included. Esophagogastric anastomosis to the posterior gastric wall was performed with a partial gastric fundoplication in the first group but simple routine anastomosis was done to the posterior gastric wall in the second group. Results: In a retrospective cohort study 100 patients entered the study with 59 male & 41 female and with a mean age 54.6±6.4 years. Squamous cell carcinoma was observed in 77% of the patients and adenocarcinoma was reported in 23% of them. Seventy-two percent of tumours were located in distal third and 28% were in middle third of esophagus. Esophagogastric anastomotic leakage was observed in 3 cases of fundoplication group and 7 cases of simple anastomosis technique (P=0.182 so there was no significant difference between the two groups. Benign anastomosis stricture was reported in one of the patients who underwent esophagogastric anastomosis with fundoplication, but it was observed in 8 cases with simple anastomosis technique (P=0.03 so there was a significant difference between the two groups. Conclusion: Esophagogastric anastomosis with partial fundal fundoplication is a safe technique with low incidence of anatomic leakage and late stenosis.

  18. Rovibrational controlled-NOT gates using optimized stimulated Raman adiabatic passage techniques and optimal control theory

    International Nuclear Information System (INIS)

    Sugny, D.; Bomble, L.; Ribeyre, T.; Dulieu, O.; Desouter-Lecomte, M.

    2009-01-01

    Implementation of quantum controlled-NOT (CNOT) gates in realistic molecular systems is studied using stimulated Raman adiabatic passage (STIRAP) techniques optimized in the time domain by genetic algorithms or coupled with optimal control theory. In the first case, with an adiabatic solution (a series of STIRAP processes) as starting point, we optimize in the time domain different parameters of the pulses to obtain a high fidelity in two realistic cases under consideration. A two-qubit CNOT gate constructed from different assignments in rovibrational states is considered in diatomic (NaCs) or polyatomic (SCCl 2 ) molecules. The difficulty of encoding logical states in pure rotational states with STIRAP processes is illustrated. In such circumstances, the gate can be implemented by optimal control theory and the STIRAP sequence can then be used as an interesting trial field. We discuss the relative merits of the two methods for rovibrational computing (structure of the control field, duration of the control, and efficiency of the optimization).

  19. Airfoil shape optimization using non-traditional optimization technique and its validation

    Directory of Open Access Journals (Sweden)

    R. Mukesh

    2014-07-01

    Full Text Available Computational fluid dynamics (CFD is one of the computer-based solution methods which is more widely employed in aerospace engineering. The computational power and time required to carry out the analysis increase as the fidelity of the analysis increases. Aerodynamic shape optimization has become a vital part of aircraft design in the recent years. Generally if we want to optimize an airfoil we have to describe the airfoil and for that, we need to have at least hundred points of x and y co-ordinates. It is really difficult to optimize airfoils with this large number of co-ordinates. Nowadays many different schemes of parameter sets are used to describe general airfoil such as B-spline, and PARSEC. The main goal of these parameterization schemes is to reduce the number of needed parameters as few as possible while controlling the important aerodynamic features effectively. Here the work has been done on the PARSEC geometry representation method. The objective of this work is to introduce the knowledge of describing general airfoil using twelve parameters by representing its shape as a polynomial function. And also we have introduced the concept of Genetic Algorithm to optimize the aerodynamic characteristics of a general airfoil for specific conditions. A MATLAB program has been developed to implement PARSEC, Panel Technique, and Genetic Algorithm. This program has been tested for a standard NACA 2411 airfoil and optimized to improve its coefficient of lift. Pressure distribution and co-efficient of lift for airfoil geometries have been calculated using the Panel method. The optimized airfoil has improved co-efficient of lift compared to the original one. The optimized airfoil is validated using wind tunnel data.

  20. Surgical technique for ambulatory management of airsacculitis in a chimpanzee (Pan troglodytes).

    Science.gov (United States)

    Hill, L R; Lee, D R; Keeling, M E

    2001-02-01

    Bacterial infections of the air sac have been reported in many nonhuman primates. Approaches to the management of airsacculitis have included combinations of medical and surgical therapies. These strategies have often required repeated attempts to drain exudate from the affected air sac, as well as necessitating that the animal endure isolation or undergo intensive postoperative care before returning to its social group. A stoma was created via deliberate apposition of the air sac lining and skin to allow continuous drainage. Antibiotic therapy based on culture and antimicrobial susceptibility of the air sac contents was administered while the chimpanzee remained in its social group. We were able to attain complete resolution of the infection after a course of oral antibiotic therapy. The stoma closed gradually over a three-week period, and the chimpanzee has remained free of infection since that time. Despite the severity of the air sac infection in this chimpanzee, we were able to resolve the infection easily, using a simple surgical technique. This method allowed treatment without interfering with social standing or subjection to repeated anesthetic and treatment episodes. This method could be a simple, useful alternative for managing airsacculitis in nonhuman primates.

  1. Postero-Inferior Pedicle Surgical Technique for the Treatment of Grade III Gynecomastia.

    Science.gov (United States)

    Thiénot, Sophie; Bertheuil, Nicolas; Carloni, Raphaël; Méal, Cécile; Aillet, Sylvie; Herlin, Christian; Watier, Eric

    2017-06-01

    Surgical treatment of Grade III gynecomastia generally utilizes mastectomy techniques and free transplantation of the nipple-areola complex. Moreover, with rising obesity rates and the development of bariatric surgery, an increasing demand for correctional surgery for pseudogynecomastia has been observed, which is comparable to Grade III gynecomastia in terms of its surgical management. Here, we describe an innovative technique to deal with these new demands: fascio-cutaneous flap by postero-inferior pedicle. All patients in the Department of Plastic Surgery from our University Hospital suffering from Grade III gynecomastia or pseudogynecomastia underwent surgery via the postero-inferior pedicle flap technique. Briefly, we performed extensive liposuction of the infero-internal and infero-external mammary quadrants followed by liposuction of the deep tissues of the superior quadrants, except in the area of the pedicle. After removing the skin just above the dermis of the inferior quadrants and performing de-epithelialization of the postero-inferior pedicle flap, the thoracic flap was lowered and the areola transposed. Nine patients underwent surgery between March 2015 and March 2016, and their results were collected prospectively. The mean patient age was 46.6 years, the mean weight was 94.2 kg, and the mean body mass index was 30.8 kg/m 2 . In addition, the mean operative time was 132 min, the mean liposuction volume was 633 mL, the excised weight was 586 g, and the mean hospitalization and drainage durations were 3.8 days. No major complications occurred, no re-intervention was required, and no recurrence was found. We report a new operative technique using a postero-inferior pedicle. Its main advantage is preservation of neurovascular function, which makes this a promising technique for patients who wish to maintain nipple sensitivity. This surgery is reliable and reproducible. We recommend it as the first line treatment for Grade III gynecomastia because

  2. Essays on variational approximation techniques for stochastic optimization problems

    Science.gov (United States)

    Deride Silva, Julio A.

    This dissertation presents five essays on approximation and modeling techniques, based on variational analysis, applied to stochastic optimization problems. It is divided into two parts, where the first is devoted to equilibrium problems and maxinf optimization, and the second corresponds to two essays in statistics and uncertainty modeling. Stochastic optimization lies at the core of this research as we were interested in relevant equilibrium applications that contain an uncertain component, and the design of a solution strategy. In addition, every stochastic optimization problem relies heavily on the underlying probability distribution that models the uncertainty. We studied these distributions, in particular, their design process and theoretical properties such as their convergence. Finally, the last aspect of stochastic optimization that we covered is the scenario creation problem, in which we described a procedure based on a probabilistic model to create scenarios for the applied problem of power estimation of renewable energies. In the first part, Equilibrium problems and maxinf optimization, we considered three Walrasian equilibrium problems: from economics, we studied a stochastic general equilibrium problem in a pure exchange economy, described in Chapter 3, and a stochastic general equilibrium with financial contracts, in Chapter 4; finally from engineering, we studied an infrastructure planning problem in Chapter 5. We stated these problems as belonging to the maxinf optimization class and, in each instance, we provided an approximation scheme based on the notion of lopsided convergence and non-concave duality. This strategy is the foundation of the augmented Walrasian algorithm, whose convergence is guaranteed by lopsided convergence, that was implemented computationally, obtaining numerical results for relevant examples. The second part, Essays about statistics and uncertainty modeling, contains two essays covering a convergence problem for a sequence

  3. [Cardiac myxoma -- the influence of preoperative clinical presentation and surgical technique on late outcome].

    Science.gov (United States)

    Mikić, Aleksandar; Obrenović-Krcanski, Bilijana; Kocica, Mladen; Vranes, Mile; Lacković, Vesna; Velinović, Milos; Miarković, Miroslav; Kovacević, Natasa; Djukić, Petar

    2007-01-01

    Cardiac myxomas are the most frequent primary tumours of the heart in adults, and they can be found in each of four cardiac chambers. Although biologically benign, due to their unfavourable localization, myxomas are considered "functionally malignant" tumours. Diagnosis of cardiac myxoma necessitates surgical treatment. To analyse: 1) the influence of localization, size and consistency of cardiac myxomas on preoperative symptomatology; 2) the influence of different surgical techniques (left, right, biatrial approach, tumour basis solving) on early, and late outcomes. From 1982 to 2000, at the Institute for Cardiovascular Diseases, Clinical Centre of Serbia, there were 46 patients with cardiac myxomas operated on, 67.4% of them women, mean age 47.1 +/- 16.3 years. The diagnosis was made according to clinical presentation, electrocardiographic and echocardiographic examinations and cardiac catheterization. Follow-up period was 4-18 (mean 7.8) years. In 41 (89.1%) patients, myxoma was localized in the left, while in 5 (10.9%), it was found in the right atrium. Average size was 5.8 x 3.8 cm (range: 1 x l cm to 9 x 8 cm) and 6 x 4 cm (range: 3 x 2 cm to 9 x 5 cm) for the left and right atrial myxomas, respectively. A racemous form predominated in the left (82.6%) and globous in the right (80%) atrium. Fatigue was the most common general (84.8%) and dyspnoea the most common cardiologic symptom (73.9%). Preoperative embolic events were present in 8 patients (4 pulmonary, 4 systemic). In our series: 1) different localization, size and consistency had no influence on the preoperative symptomatology; 2) surgical treatment applied, regardless of different approaches and basis solving, resulted in excellent functional improvements (63.1% patients in NYHA III and IV class preoperatively vs. 6.7% patients postoperatively) and had no influence on new postoperative rhythm disturbances (8.7% patients preoperatively vs. 24.4% patients postoperatively); 3) early (97.8%), and late

  4. Optimal primary surgical management of infected pseudoaneurysm in intravenous drug abusers: ligation or reconstruction?

    International Nuclear Information System (INIS)

    Jamil, M.; Usman, R.; Afzal, M.; Malik, N.I.

    2017-01-01

    Objective: To find out the optimal primary surgical treatment options for infected pseudoaneurysm in intravenous drug abusers. Study Design: Cross sectional descriptive study. Place and Duration of Study: Department of Vascular Surgery, Combined Military Hospital Lahore, from Jan 2010 to Jun 2015. Material and Methods: A total of 31 consecutive patients with a history of intravenous drug abuse and an infected pseudoaneurysm in the groin or elbow, presenting in emergency department; were included in this study. All patients were primarily treated with ligation of the artery, excision of infected pseudoaneurysm and debridement of necrotic tissues. Only one patient underwent additional revascularization procedure. Results: All patients who underwent ligation and excision procedures did well initially. One (3.2%) patient developed severe distal ischemia after ligation of femoral artery within first 24 hours, so extra anatomic revascularization procedure was performed. Five (16.1%) patients required revascularization procedure after 16 weeks due to disabling distal ischemia. No amputation was needed and mortality rate was zero. Conclusion: Primary ligation of the artery with excision of infected pseudoaneurysm and necrotic material was found the optimal initial management for infected pseudoaneurysm in intravenous drug addicts. Ischemic complications if develop should be treated with early or late revascularization.

  5. A review of the surgical management of breast cancer: plastic reconstructive techniques and timing implications.

    Science.gov (United States)

    Rosson, Gedge D; Magarakis, Michael; Shridharani, Sachin M; Stapleton, Sahael M; Jacobs, Lisa K; Manahan, Michele A; Flores, Jaime I

    2010-07-01

    The oncologic management of breast cancer has evolved over the past several decades from radical mastectomy to modern-day preservation of chest and breast structures. The increased rate of mastectomies over recent years made breast reconstruction an integral part of the breast cancer management. Plastic surgery now offers patients a wide variety of reconstruction options from primary closure of the skin flaps to performance of microvascular and autologous tissue transplantation. Well-coordinated partnerships between surgical oncologists, plastic surgeons, and patients address concerns of tumor control, cosmesis, and patients' wishes. The gamut of breast reconstruction options is reviewed, particularly noting state-of-the-art techniques, as well as the advantages and disadvantages of various timing modalities.

  6. Traumatic intercostal arterial bleeding controlled with a novel surgical technique: a case report

    Directory of Open Access Journals (Sweden)

    Miettinen Simo

    2012-09-01

    Full Text Available Abstract Introduction A blunt thoracic trauma may cause arterial bleeding requiring operative treatment or endovascular embolization or endovascular aortic stenting. A novel damage control technique to stop such bleeding is presented. Case presentation We present the case of an 82-year-old Caucasian man who experienced rib fractures I-VII on the left side and bleeding from damaged intercostal arteries after a blunt thoracic trauma. Emergency thoracotomy was performed. Conclusions Effective hemostasis was achieved by using a rolled surgical swab and inserting it against the chest wall next to the aorta with sutures pulled through the intercostal muscles and then sutured to the back side of the patient. The patient died four days after the surgery due to a head injury sustained in the car crash.

  7. Ex-vivo partial nephrectomy after living donor nephrectomy: Surgical technique for expanding kidney donor pool

    Directory of Open Access Journals (Sweden)

    Yaw A Nyame

    2017-01-01

    Full Text Available Renal transplantation has profound improvements in mortality, morbidity, and overall quality of life compared to renal replacement therapy. This report aims to illustrate the use of ex-vivo partial nephrectomy in a patient with a renal angiomyolipoma prior to living donor transplantation. The surgical outcomes of the donor nephrectomy and recipient transplantation are reported with 2 years of follow-up. Both the donor and recipient are healthy and without any significant comorbidities. In conclusion, urologic techniques such as partial nephrectomy can be used to expand the living donor pool in carefully selected and well informed transplant recipients. Our experience demonstrated a safe and positive outcome for both the recipient and donor, and is consistent with other reported outcomes in the literature.

  8. Use of 3D Printed Bone Plate in Novel Technique to Surgically Correct Hallux Valgus Deformities

    Science.gov (United States)

    Smith, Kathryn E.; Dupont, Kenneth M.; Safranski, David L.; Blair, Jeremy; Buratti, Dawn; Zeetser, Vladimir; Callahan, Ryan; Lin, Jason; Gall, Ken

    2016-01-01

    Three-dimensional (3-D) printing offers many potential advantages in designing and manufacturing plating systems for foot and ankle procedures that involve small, geometrically complex bony anatomy. Here, we describe the design and clinical use of a Ti-6Al-4V ELI bone plate (FastForward™ Bone Tether Plate, MedShape, Inc., Atlanta, GA) manufactured through 3-D printing processes. The plate protects the second metatarsal when tethering suture tape between the first and second metatarsals and is a part of a new procedure that corrects hallux valgus (bunion) deformities without relying on doing an osteotomy or fusion procedure. The surgical technique and two clinical cases describing the use of this procedure with the 3-D printed bone plate are presented within. PMID:28337049

  9. Techniques for optimizing nanotips derived from frozen taylor cones

    Science.gov (United States)

    Hirsch, Gregory

    2017-12-05

    Optimization techniques are disclosed for producing sharp and stable tips/nanotips relying on liquid Taylor cones created from electrically conductive materials with high melting points. A wire substrate of such a material with a preform end in the shape of a regular or concave cone, is first melted with a focused laser beam. Under the influence of a high positive potential, a Taylor cone in a liquid/molten state is formed at that end. The cone is then quenched upon cessation of the laser power, thus freezing the Taylor cone. The tip of the frozen Taylor cone is reheated by the laser to allow its precise localized melting and shaping. Tips thus obtained yield desirable end-forms suitable as electron field emission sources for a variety of applications. In-situ regeneration of the tip is readily accomplished. These tips can also be employed as regenerable bright ion sources using field ionization/desorption of introduced chemical species.

  10. Neoliberal Optimism: Applying Market Techniques to Global Health.

    Science.gov (United States)

    Mei, Yuyang

    2017-01-01

    Global health and neoliberalism are becoming increasingly intertwined as organizations utilize markets and profit motives to solve the traditional problems of poverty and population health. I use field work conducted over 14 months in a global health technology company to explore how the promise of neoliberalism re-envisions humanitarian efforts. In this company's vaccine refrigerator project, staff members expect their investors and their market to allow them to achieve scale and develop accountability to their users in developing countries. However, the translation of neoliberal techniques to the global health sphere falls short of the ideal, as profits are meager and purchasing power remains with donor organizations. The continued optimism in market principles amidst such a non-ideal market reveals the tenacious ideological commitment to neoliberalism in these global health projects.

  11. Robotic transverse colectomy for mid-transverse colon cancer: surgical techniques and oncologic outcomes.

    Science.gov (United States)

    Jung, Kyung Uk; Park, Yoonah; Lee, Kang Young; Sohn, Seung-Kook

    2015-06-01

    Robot-assisted surgery for colon cancer has been reported in many studies, most of which worked on right and/or sigmoid colectomy. The aim of this study was to report our experience of robotic transverse colectomy with an intracorporeal anastomosis, provide details of the surgical technique, and present the theoretical benefits of the procedure. This is a retrospective review of prospectively collected data of robotic surgery for colorectal cancer performed by a single surgeon between May 2007 and February 2011. Out of 162 consecutive cases, we identified three robotic transverse colectomies, using a hand-sewn intracorporeal anastomosis. Two males and one female underwent transverse colectomies for malignant or premalignant disease. The mean docking time, time spent using the robot, and total operative time were 5, 268, and 307 min, respectively. There were no conversions to open or conventional laparoscopic technique. The mean length of specimen and number of lymph nodes retrieved were 14.1 cm and 6.7, respectively. One patient suffered from a wound seroma and recovered with conservative management. The mean hospital stay was 8.7 days. After a median follow-up of 72 months, there were no local or systemic recurrences. Robotic transverse colectomy seems to be a safe and feasible technique. It may minimize the necessity of mobilizing both colonic flexures, with facilitated intracorporeal hand-sewn anastomosis. However, further prospective studies with a larger number of patients are required to draw firm conclusions.

  12. Surgical treatment of an acquired posterior urethral diverticulum with cystoscopy assisted robotic technique.

    Science.gov (United States)

    Guneri, Cagri; Kirac, Mustafa; Biri, Hasan

    2017-03-01

    A 42-year-old man with a history of recurrent urethral stenosis, recurrent urinary tract infection and macroscopic hematuria has referred to our clinic. He underwent several internal urethrotomies and currently using clean intermittent self-catheterization. During the internal urethrotomy, we noted a large posterior urethral diverticulum (UD) between verumontanum and bladder neck. His obstructive symptoms were resolved after the catheter removal. But perineal discomfort, urgency and dysuria were prolonged about 3-4 weeks. Urinalysis and urine culture confirmed recurrent urinary tract infections. Due to this conditions and symptoms, we planned a surgical approach which was planned as transperitoneal robotic-assisted laparoscopic approach. This technique is still applied for the diverticulectomy of the bladder. In addition to this we utilized the cystoscopy equipments for assistance. During this process, cystoscope was placed in the UD to help the identification of UD from adjacent tissues like seminal vesicles by its movement and translumination. Operating time was 185 min. On the post-operative third day he was discharged. Foley catheter was removed after 2 weeks. Urination was quite satisfactory. His perineal discomfort was resolved. The pathology report confirmed epidermoid (tailgut) cyst of the prostate. Urethrogram showed no radiologic signs of UD after 4 weeks. Irritative and obstructive symptoms were completely resolved after 3 months. No urinary incontinence, erectile dysfunction or retrograde ejaculation was noted. While posterior UD is an extremely rare situation, surgical treatment of posterior UD remains uncertain. To our knowledge, no above-mentioned cystoscopy assisted robotic technique for the treatment was described in the literature.

  13. Surgical technique for en bloc transurethral resection of bladder tumour with a Hybrid Knife(®).

    Science.gov (United States)

    Islas-García, J J O; Campos-Salcedo, J G; López-Benjume, B I; Torres-Gómez, J J; Aguilar-Colmenero, J; Martínez-Alonso, I A; Gil-Villa, S A

    2016-05-01

    Bladder cancer is the second most common malignancy of the urinary tract and the 9th worldwide. Latin American has an incidence of 5.6 per 100,000 inhabitants per year. Seventy-five percent of newly diagnosed cases are nonmuscle invasive bladder cancer, and 25% of cases present as muscle invasive. The mainstay of treatment for nonmuscle invasive bladder cancer is loop transurethral resection. In 2013, the group led by Dr Mundhenk of the University Hospital of Tübingen, Germany, was the first to describe the Hybrid Knife(®) equipment for performing en bloc bladder tumour resection, with favourable functional and oncological results. To describe the surgical technique of en bloc bladder tumour resection with a Hybrid Knife(®) as an alternative treatment for nonmuscle invasive bladder tumours. A male patient was diagnosed by urotomography and urethrocystoscopy with a bladder tumour measuring 2×1cm on the floor. En bloc transurethral resection of the bladder tumour was performed with a Hybrid Knife(®). Surgery was performed for 35min, with 70 watts for cutting and 50 watts for coagulation, resecting and evacuating en bloc the bladder tumour, which macroscopically included the muscle layer of the bladder. There were no complications. The technique of en bloc bladder tumour resection with Hybrid Knife(®) is an effective alternative to bipolar loop transurethral resection. Resection with a Hybrid Knife(®) is a procedure with little bleeding and good surgical vision and minimises the risk of bladder perforation and tumour implants. The procedure facilitates determining the positivity of the neoplastic process, vascular infiltration and bladder muscle invasion in the histopathology study. Copyright © 2015 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Optimization Techniques for Dimensionally Truncated Sparse Grids on Heterogeneous Systems

    KAUST Repository

    Deftu, A.

    2013-02-01

    Given the existing heterogeneous processor landscape dominated by CPUs and GPUs, topics such as programming productivity and performance portability have become increasingly important. In this context, an important question refers to how can we develop optimization strategies that cover both CPUs and GPUs. We answer this for fastsg, a library that provides functionality for handling efficiently high-dimensional functions. As it can be employed for compressing and decompressing large-scale simulation data, it finds itself at the core of a computational steering application which serves us as test case. We describe our experience with implementing fastsg\\'s time critical routines for Intel CPUs and Nvidia Fermi GPUs. We show the differences and especially the similarities between our optimization strategies for the two architectures. With regard to our test case for which achieving high speedups is a "must" for real-time visualization, we report a speedup of up to 6.2x times compared to the state-of-the-art implementation of the sparse grid technique for GPUs. © 2013 IEEE.

  15. Re-implant of the right coronary artery: a surgical technique for the treatment of ostial lesions

    Directory of Open Access Journals (Sweden)

    Bongiovani Hércules Lisboa

    2002-01-01

    Full Text Available Previously described surgical treatment for ostial coronary artery stenosis relied on either venous or arterial bypasses or ostial patch angioplasty. These surgical procedures are performed with bovine pericardium, saphenous vein or internal thoracic artery. We describe a technique of right coronary artery re-implantation into the aorta. The procedure was performed in four patients with right coronary artery ostial stenosis along with other left coronary artery lesions.

  16. Comparative evaluation of diode laser ablation and surgical stripping technique for gingival depigmentation: A clinical and immunohistochemical study.

    Science.gov (United States)

    Bakutra, Gaurav; Shankarapillai, Rajesh; Mathur, Lalit; Manohar, Balaji

    2017-01-01

    There are various treatment modalities to remove the black patches of melanin pigmentation. The aim of the study is to clinically compare the diode laser ablation and surgical stripping technique for gingival depigmentation and to evaluate their effect on the histological changes in melanocyte activity. A total of 40 sites of 20 patients with bilateral melanin hyperpigmentation were treated with the surgical stripping and diode laser ablation technique. Change in Hedin index score, change in area of pigmentation using image analyzing software, pain perception, patient preference of treatment were recorded. All 40 sites were selected for immunohistochemical analysis using HMB-45 immunohistochemical marker. At 12 months post-operative visit, in all sites, repigmentation was observed with different grades of Hedin index. Paired t -test, analysis of variance, and Chi-square tests were used for statistical analysis. Repigmentation in surgical stripping is significantly lesser compared to laser ablation. Lesser numbers of melanocytes were found on immunohistological examination at 12 months postoperatively. Comparison for patient preference and pain indices give statistically significant values for diode laser techniques. Gingival hyperpigmentation is effectively managed by diode laser ablation technique and surgical stripping method. In this study, surgical stripping technique found to be better compared to diode laser ablation.

  17. Does the Implant Surgical Technique Affect the Primary and/or Secondary Stability of Dental Implants? A Systematic Review

    Science.gov (United States)

    Shadid, Rola Muhammed; Sadaqah, Nasrin Rushdi; Othman, Sahar Abdo

    2014-01-01

    Background. A number of surgical techniques for implant site preparation have been advocated to enhance the implant of primary and secondary stability. However, there is insufficient scientific evidence to support the association between the surgical technique and implant stability. Purpose. This review aimed to investigate the influence of different surgical techniques including the undersized drilling, the osteotome, the piezosurgery, the flapless procedure, and the bone stimulation by low-level laser therapy on the primary and/or secondary stability of dental implants. Materials and methods. A search of PubMed, Cochrane Library, and grey literature was performed. The inclusion criteria comprised observational clinical studies and randomized controlled trials (RCTs) conducted in patients who received dental implants for rehabilitation, studies that evaluated the association between the surgical technique and the implant primary and/or secondary stability. The articles selected were carefully read and classified as low, moderate, and high methodological quality and data of interest were tabulated. Results. Eight clinical studies were included then they were classified as moderate or high methodological quality and control of bias. Conclusions. There is a weak evidence suggesting that any of previously mentioned surgical techniques could influence the primary and/or secondary implant stability. PMID:25126094

  18. Does the Implant Surgical Technique Affect the Primary and/or Secondary Stability of Dental Implants? A Systematic Review

    Directory of Open Access Journals (Sweden)

    Rola Muhammed Shadid

    2014-01-01

    Full Text Available Background. A number of surgical techniques for implant site preparation have been advocated to enhance the implant of primary and secondary stability. However, there is insufficient scientific evidence to support the association between the surgical technique and implant stability. Purpose. This review aimed to investigate the influence of different surgical techniques including the undersized drilling, the osteotome, the piezosurgery, the flapless procedure, and the bone stimulation by low-level laser therapy on the primary and/or secondary stability of dental implants. Materials and methods. A search of PubMed, Cochrane Library, and grey literature was performed. The inclusion criteria comprised observational clinical studies and randomized controlled trials (RCTs conducted in patients who received dental implants for rehabilitation, studies that evaluated the association between the surgical technique and the implant primary and/or secondary stability. The articles selected were carefully read and classified as low, moderate, and high methodological quality and data of interest were tabulated. Results. Eight clinical studies were included then they were classified as moderate or high methodological quality and control of bias. Conclusions. There is a weak evidence suggesting that any of previously mentioned surgical techniques could influence the primary and/or secondary implant stability.

  19. Optimization of a Fuzzy-Logic-Control-Based MPPT Algorithm Using the Particle Swarm Optimization Technique

    Directory of Open Access Journals (Sweden)

    Po-Chen Cheng

    2015-06-01

    Full Text Available In this paper, an asymmetrical fuzzy-logic-control (FLC-based maximum power point tracking (MPPT algorithm for photovoltaic (PV systems is presented. Two membership function (MF design methodologies that can improve the effectiveness of the proposed asymmetrical FLC-based MPPT methods are then proposed. The first method can quickly determine the input MF setting values via the power–voltage (P–V curve of solar cells under standard test conditions (STC. The second method uses the particle swarm optimization (PSO technique to optimize the input MF setting values. Because the PSO approach must target and optimize a cost function, a cost function design methodology that meets the performance requirements of practical photovoltaic generation systems (PGSs is also proposed. According to the simulated and experimental results, the proposed asymmetrical FLC-based MPPT method has the highest fitness value, therefore, it can successfully address the tracking speed/tracking accuracy dilemma compared with the traditional perturb and observe (P&O and symmetrical FLC-based MPPT algorithms. Compared to the conventional FLC-based MPPT method, the obtained optimal asymmetrical FLC-based MPPT can improve the transient time and the MPPT tracking accuracy by 25.8% and 0.98% under STC, respectively.

  20. Optimization of DNA Sensor Model Based Nanostructured Graphene Using Particle Swarm Optimization Technique

    Directory of Open Access Journals (Sweden)

    Hediyeh Karimi

    2013-01-01

    Full Text Available It has been predicted that the nanomaterials of graphene will be among the candidate materials for postsilicon electronics due to their astonishing properties such as high carrier mobility, thermal conductivity, and biocompatibility. Graphene is a semimetal zero gap nanomaterial with demonstrated ability to be employed as an excellent candidate for DNA sensing. Graphene-based DNA sensors have been used to detect the DNA adsorption to examine a DNA concentration in an analyte solution. In particular, there is an essential need for developing the cost-effective DNA sensors holding the fact that it is suitable for the diagnosis of genetic or pathogenic diseases. In this paper, particle swarm optimization technique is employed to optimize the analytical model of a graphene-based DNA sensor which is used for electrical detection of DNA molecules. The results are reported for 5 different concentrations, covering a range from 0.01 nM to 500 nM. The comparison of the optimized model with the experimental data shows an accuracy of more than 95% which verifies that the optimized model is reliable for being used in any application of the graphene-based DNA sensor.

  1. Optimal technique for deep breathing exercises after cardiac surgery.

    Science.gov (United States)

    Westerdahl, E

    2015-06-01

    Cardiac surgery patients often develop a restrictive pulmonary impairment and gas exchange abnormalities in the early postoperative period. Chest physiotherapy is routinely prescribed in order to reduce or prevent these complications. Besides early mobilization, positioning and shoulder girdle exercises, various breathing exercises have been implemented as a major component of postoperative care. A variety of deep breathing maneuvres are recommended to the spontaneously breathing patient to reduce atelectasis and to improve lung function in the early postoperative period. Different breathing exercises are recommended in different parts of the world, and there is no consensus about the most effective breathing technique after cardiac surgery. Arbitrary instructions are given, and recommendations on performance and duration vary between hospitals. Deep breathing exercises are a major part of this therapy, but scientific evidence for the efficacy has been lacking until recently, and there is a lack of trials describing how postoperative breathing exercises actually should be performed. The purpose of this review is to provide a brief overview of postoperative breathing exercises for patients undergoing cardiac surgery via sternotomy, and to discuss and suggest an optimal technique for the performance of deep breathing exercises.

  2. A Monte Carlo simulation technique to determine the optimal portfolio

    Directory of Open Access Journals (Sweden)

    Hassan Ghodrati

    2014-03-01

    Full Text Available During the past few years, there have been several studies for portfolio management. One of the primary concerns on any stock market is to detect the risk associated with various assets. One of the recognized methods in order to measure, to forecast, and to manage the existing risk is associated with Value at Risk (VaR, which draws much attention by financial institutions in recent years. VaR is a method for recognizing and evaluating of risk, which uses the standard statistical techniques and the method has been used in other fields, increasingly. The present study has measured the value at risk of 26 companies from chemical industry in Tehran Stock Exchange over the period 2009-2011 using the simulation technique of Monte Carlo with 95% confidence level. The used variability in the present study has been the daily return resulted from the stock daily price change. Moreover, the weight of optimal investment has been determined using a hybrid model called Markowitz and Winker model in each determined stocks. The results showed that the maximum loss would not exceed from 1259432 Rials at 95% confidence level in future day.

  3. A Novel Surgical Pre-suturing Technique for the Management of ...

    African Journals Online (AJOL)

    cannot be protruded beyond lower incisor teeth because of a short lingual ... suggests that surgical interventions are absolutely safe at any age including ... Surgical procedures indicated for ankyloglossia are highly predictable but shows poor ...

  4. Design-Based Comparison of Spine Surgery Simulators: Optimizing Educational Features of Surgical Simulators.

    Science.gov (United States)

    Ryu, Won Hyung A; Mostafa, Ahmed E; Dharampal, Navjit; Sharlin, Ehud; Kopp, Gail; Jacobs, W Bradley; Hurlbert, R John; Chan, Sonny; Sutherland, Garnette R

    2017-10-01

    Simulation-based education has made its entry into surgical residency training, particularly as an adjunct to hands-on clinical experience. However, one of the ongoing challenges to wide adoption is the capacity of simulators to incorporate educational features required for effective learning. The aim of this study was to identify strengths and limitations of spine simulators to characterize design elements that are essential in enhancing resident education. We performed a mixed qualitative and quantitative cohort study with a focused survey and interviews of stakeholders in spine surgery pertaining to their experiences on 3 spine simulators. Ten participants were recruited spanning all levels of training and expertise until qualitative analysis reached saturation of themes. Participants were asked to perform lumbar pedicle screw insertion on 3 simulators. Afterward, a 10-item survey was administrated and a focused interview was conducted to explore topics pertaining to the design features of the simulators. Overall impressions of the simulators were positive with regards to their educational benefit, but our qualitative analysis revealed differing strengths and limitations. Main design strengths of the computer-based simulators were incorporation of procedural guidance and provision of performance feedback. The synthetic model excelled in achieving more realistic haptic feedback and incorporating use of actual surgical tools. Stakeholders from trainees to experts acknowledge the growing role of simulation-based education in spine surgery. However, different simulation modalities have varying design elements that augment learning in distinct ways. Characterization of these design characteristics will allow for standardization of simulation curricula in spinal surgery, optimizing educational benefit. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Real-time surgical simulation for deformable soft-tissue objects with a tumour using Boundary Element techniques

    Science.gov (United States)

    Wang, P.; Becker, A. A.; Jones, I. A.; Glover, A. T.; Benford, S. D.; Vloeberghs, M.

    2009-08-01

    A virtual-reality real-time simulation of surgical operations that incorporates the inclusion of a hard tumour is presented. The software is based on Boundary Element (BE) technique. A review of the BE formulation for real-time analysis of two-domain deformable objects, using the pre-solution technique, is presented. The two-domain BE software is incorporated into a surgical simulation system called VIRS to simulate the initiation of a cut on the surface of the soft tissue and extending the cut deeper until the tumour is reached.

  6. Real-time surgical simulation for deformable soft-tissue objects with a tumour using Boundary Element techniques

    International Nuclear Information System (INIS)

    Wang, P; Becker, A A; Jones, I A; Glover, A T; Benford, S D; Vloeberghs, M

    2009-01-01

    A virtual-reality real-time simulation of surgical operations that incorporates the inclusion of a hard tumour is presented. The software is based on Boundary Element (BE) technique. A review of the BE formulation for real-time analysis of two-domain deformable objects, using the pre-solution technique, is presented. The two-domain BE software is incorporated into a surgical simulation system called VIRS to simulate the initiation of a cut on the surface of the soft tissue and extending the cut deeper until the tumour is reached.

  7. Breast Cancer-Related Arm Lymphedema: Incidence Rates, Diagnostic Techniques, Optimal Management and Risk Reduction Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Chirag [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Vicini, Frank A., E-mail: fvicini@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States)

    2011-11-15

    As more women survive breast cancer, long-term toxicities affecting their quality of life, such as lymphedema (LE) of the arm, gain importance. Although numerous studies have attempted to determine incidence rates, identify optimal diagnostic tests, enumerate efficacious treatment strategies and outline risk reduction guidelines for breast cancer-related lymphedema (BCRL), few groups have consistently agreed on any of these issues. As a result, standardized recommendations are still lacking. This review will summarize the latest data addressing all of these concerns in order to provide patients and health care providers with optimal, contemporary recommendations. Published incidence rates for BCRL vary substantially with a range of 2-65% based on surgical technique, axillary sampling method, radiation therapy fields treated, and the use of chemotherapy. Newer clinical assessment tools can potentially identify BCRL in patients with subclinical disease with prospective data suggesting that early diagnosis and management with noninvasive therapy can lead to excellent outcomes. Multiple therapies exist with treatments defined by the severity of BCRL present. Currently, the standard of care for BCRL in patients with significant LE is complex decongestive physiotherapy (CDP). Contemporary data also suggest that a multidisciplinary approach to the management of BCRL should begin prior to definitive treatment for breast cancer employing patient-specific surgical, radiation therapy, and chemotherapy paradigms that limit risks. Further, prospective clinical assessments before and after treatment should be employed to diagnose subclinical disease. In those patients who require aggressive locoregional management, prophylactic therapies and the use of CDP can help reduce the long-term sequelae of BCRL.

  8. Breast Cancer-Related Arm Lymphedema: Incidence Rates, Diagnostic Techniques, Optimal Management and Risk Reduction Strategies

    International Nuclear Information System (INIS)

    Shah, Chirag; Vicini, Frank A.

    2011-01-01

    As more women survive breast cancer, long-term toxicities affecting their quality of life, such as lymphedema (LE) of the arm, gain importance. Although numerous studies have attempted to determine incidence rates, identify optimal diagnostic tests, enumerate efficacious treatment strategies and outline risk reduction guidelines for breast cancer–related lymphedema (BCRL), few groups have consistently agreed on any of these issues. As a result, standardized recommendations are still lacking. This review will summarize the latest data addressing all of these concerns in order to provide patients and health care providers with optimal, contemporary recommendations. Published incidence rates for BCRL vary substantially with a range of 2–65% based on surgical technique, axillary sampling method, radiation therapy fields treated, and the use of chemotherapy. Newer clinical assessment tools can potentially identify BCRL in patients with subclinical disease with prospective data suggesting that early diagnosis and management with noninvasive therapy can lead to excellent outcomes. Multiple therapies exist with treatments defined by the severity of BCRL present. Currently, the standard of care for BCRL in patients with significant LE is complex decongestive physiotherapy (CDP). Contemporary data also suggest that a multidisciplinary approach to the management of BCRL should begin prior to definitive treatment for breast cancer employing patient-specific surgical, radiation therapy, and chemotherapy paradigms that limit risks. Further, prospective clinical assessments before and after treatment should be employed to diagnose subclinical disease. In those patients who require aggressive locoregional management, prophylactic therapies and the use of CDP can help reduce the long-term sequelae of BCRL.

  9. Comparison of two surgical techniques for creating an acute myocardial infarct in rats

    Directory of Open Access Journals (Sweden)

    Luiz Guilherme Achcar Capriglione

    2014-12-01

    Full Text Available Objective: To perform a comparative assessment of two surgical techniques that are used creating an acute myocardial infarc by occluding the left anterior descending coronary artery in order to generate rats with a left ventricular ejection fraction of less than 40%. Methods: The study was completely randomized and comprised 89 halothane-anaesthetised rats, which were divided into three groups. The control group (SHAM comprised fourteen rats, whose left anterior descending coronary artery was not occluded. Group 1 (G1: comprised by 35 endotracheally intubated and mechanically ventilated rats, whose left anterior descending coronary artery was occluded. Group 2 (G2: comprised 40 rats being manually ventilated using a nasal respirator whose left anterior descending coronary artery was occluded. Other differences between the two techniques include the method of performing the thoracotomy and removing the pericardium in order to expose the heart, and the use of different methods and suture types for closing the thorax. Seven days after surgery, the cardiac function of all surviving rats was determined by echocardiography. Results: No rats SHAM group had progressed to death or had left ventricular ejection fraction less than 40%. Nine of the 16 surviving G1 rats (56.3% and six of the 20 surviving G2 rats (30% had a left ventricular ejection fraction of less than 40%. Conclusion: The results indicate a tendency of the technique used in G1 to be better than in G2. This improvement is probably due to the greater duration of the open thorax, which reduces the pressure over time from the surgeon, allowing occlusion of left anterior descending coronary artery with higher accuracy.

  10. Current surgical practices in cleft care: cleft palate repair techniques and postoperative care.

    Science.gov (United States)

    Katzel, Evan B; Basile, Patrick; Koltz, Peter F; Marcus, Jeffrey R; Girotto, John A

    2009-09-01

    The purpose of this study was to objectively report practices commonly used in cleft palate repair in the United States. This study investigates current surgical techniques, postoperative care, and complication rates for cleft palate repair surgery. All 803 surgeon members of the American Cleft Palate-Craniofacial Association were sent online and/or paper surveys inquiring about their management of cleft palate patients. Three-hundred six surveys were received, a 38 percent response rate. This represented responses of surgeons from 100 percent of American Cleft Palate-Craniofacial Association registered cleft teams. Ninety-six percent of respondents perform a one-stage repair. Eighty-five percent of surgeons perform palate surgery when the patient is between 6 and 12 months of age. The most common one-stage repair techniques are the Bardach style (two flaps) with intravelar veloplasty and the Furlow palatoplasty. After surgery, 39 percent of surgeons discharge patients within 24 hours. Another 43 percent discharge patients within 48 hours. During postoperative management, 92 percent of respondents implement feeding restrictions. Eighty-five percent of physicians use arm restraints. Surgeons' self-reported complications rates are minimal: 54 percent report a fistula in less than 5 percent of cases. The reported need for secondary speech surgery varies widely. The majority of respondents repair clefts in one stage. The most frequently used repair techniques are the Furlow palatoplasty and the Bardach style with intravelar veloplasty. After surgery, the majority of surgeons discharge patients in 1 or 2 days, and nearly all surgeons implement feeding restrictions and the use of arm restraints. The varying feeding protocols are reviewed in this article.

  11. Biodegradable Magnesium Stent Treatment of Saccular Aneurysms in a Rat Model - Introduction of the Surgical Technique.

    Science.gov (United States)

    Nevzati, Edin; Rey, Jeannine; Coluccia, Daniel; D'Alonzo, Donato; Grüter, Basil; Remonda, Luca; Fandino, Javier; Marbacher, Serge

    2017-10-01

    The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable experimental animal models to test novel embolization materials such as stents and flow diverters. The aim of the present project was to design a safe, fast, and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model. Saccular aneurysms were created from an arterial graft from the descending aorta.The aneurysms were microsurgically transplanted through end-to-side anastomosis to the infrarenal abdominal aorta of a syngenic male Wistar rat weighing >500 g. Following aneurysm anastomosis, aneurysm embolization was performed using balloon expandable magnesium stents (2.5 mm x 6 mm). The stent system was retrograde introduced from the lower abdominal aorta using a modified Seldinger technique. Following a pilot series of 6 animals, a total of 67 rats were operated according to established standard operating procedures. Mean surgery time, mean anastomosis time, and mean suturing time of the artery puncture site were 167 ± 22 min, 26 ± 6 min and 11 ± 5 min, respectively. The mortality rate was 6% (n=4). The morbidity rate was 7.5% (n=5), and in-stent thrombosis was found in 4 cases (n=2 early, n=2 late in stent thrombosis). The results demonstrate the feasibility of standardized stent occlusion of saccular sidewall aneurysms in rats - with low rates of morbidity and mortality. This stent embolization procedure combines the opportunity to study novel concepts of stent or flow diverter based devices as well as the molecular aspects of healing.

  12. Use of advanced modeling techniques to optimize thermal packaging designs.

    Science.gov (United States)

    Formato, Richard M; Potami, Raffaele; Ahmed, Iftekhar

    2010-01-01

    Through a detailed case study the authors demonstrate, for the first time, the capability of using advanced modeling techniques to correctly simulate the transient temperature response of a convective flow-based thermal shipper design. The objective of this case study was to demonstrate that simulation could be utilized to design a 2-inch-wall polyurethane (PUR) shipper to hold its product box temperature between 2 and 8 °C over the prescribed 96-h summer profile (product box is the portion of the shipper that is occupied by the payload). Results obtained from numerical simulation are in excellent agreement with empirical chamber data (within ±1 °C at all times), and geometrical locations of simulation maximum and minimum temperature match well with the corresponding chamber temperature measurements. Furthermore, a control simulation test case was run (results taken from identical product box locations) to compare the coupled conduction-convection model with a conduction-only model, which to date has been the state-of-the-art method. For the conduction-only simulation, all fluid elements were replaced with "solid" elements of identical size and assigned thermal properties of air. While results from the coupled thermal/fluid model closely correlated with the empirical data (±1 °C), the conduction-only model was unable to correctly capture the payload temperature trends, showing a sizeable error compared to empirical values (ΔT > 6 °C). A modeling technique capable of correctly capturing the thermal behavior of passively refrigerated shippers can be used to quickly evaluate and optimize new packaging designs. Such a capability provides a means to reduce the cost and required design time of shippers while simultaneously improving their performance. Another advantage comes from using thermal modeling (assuming a validated model is available) to predict the temperature distribution in a shipper that is exposed to ambient temperatures which were not bracketed

  13. Identifying optimal postmarket surveillance strategies for medical and surgical devices: implications for policy, practice and research.

    Science.gov (United States)

    Gagliardi, Anna R; Umoquit, Muriah; Lehoux, Pascale; Ross, Sue; Ducey, Ariel; Urbach, David R

    2013-03-01

    Non-drug technologies offer many benefits, but have been associated with adverse events, prompting calls for improved postmarket surveillance. There is little empirical research to guide the development of such a system. The purpose of this study was to identify optimal postmarket surveillance strategies for medical and surgical devices. Qualitative methods were used for sampling, data collection and analysis. Stakeholders from Canada and the USA representing different roles and perspectives were first interviewed to identify examples and characteristics of different surveillance strategies. These stakeholders and others they recommended were then assembled at a 1-day nominal group meeting to discuss and prioritise the components of a postmarket device surveillance system, and research needed to achieve such a system. Consultations were held with 37 participants, and 47 participants attended the 1-day meeting. They recommended a multicomponent system including reporting by facilities, clinicians and patients, supported with some external surveillance for validation and real-time trials for high-risk devices. Many considerations were identified that constitute desirable characteristics of, and means by which to implement such a system. An overarching network was envisioned to broker linkages, establish a shared minimum dataset, and support communication and decision making. Numerous research questions were identified, which could be pursued in tandem with phased implementation of the system. These findings provide unique guidance for establishing a device safety network that is based on existing initiatives, and could be expanded and evaluated in a prospective, phased fashion as it was developed.

  14. Optimized inspection techniques and structural analysis in lifetime management

    International Nuclear Information System (INIS)

    Aguado, M.T.; Marcelles, I.

    1993-01-01

    Preservation of the option of extending the service lifetime of a nuclear power plant beyond its normal design lifetime requires correct remaining lifetime management from the very beginning of plant operation. The methodology used in plant remaining lifetime management is essentially based on the use of standard inspections, surveillance and monitoring programs and calculations, such as thermal-stress and fracture mechanics analysis. The inspection techniques should be continuously optimized, in order to be able to detect and dimension existing defects with the highest possible degree of accuracy. The information obtained during the inspection is combined with the historical data of the components: design, quality, operation, maintenance, and transients, and with the results of destructive testing, fracture mechanics and thermal fatigue analysis. These data are used to estimate the remaining lifetime of nuclear power plant components, systems and structures with the highest degree possible of accuracy. The use of this methodology allows component repairs and replacements to be reduced or avoided and increases the safety levels and availability of the nuclear power plant. Use of this strategy avoids the need for heavy investments at the end of the licensing period

  15. A custom three-dimensional electron bolus technique for optimization of postmastectomy irradiation

    International Nuclear Information System (INIS)

    Perkins, George H.; McNeese, Marsha D.; Antolak, John A.; Buchholz, Thomas A.; Strom, Eric A.; Hogstrom, Kenneth R.

    2001-01-01

    Purpose: Postmastectomy irradiation (PMI) is a technically complex treatment requiring consideration of the primary tumor location, possible risk of internal mammary node involvement, varying chest wall thicknesses secondary to surgical defects or body habitus, and risk of damaging normal underlying structures. In this report, we describe the application of a customized three-dimensional (3D) electron bolus technique for delivering PMI. Methods and Materials: A customized electron bolus was designed using a 3D planning system. Computed tomography (CT) images of each patient were obtained in treatment position and the volume to be treated was identified. The distal surface of the wax bolus matched the skin surface, and the proximal surface was designed to conform to the 90% isodose surface to the distal surface of the planning target volume (PTV). Dose was calculated with a pencil-beam algorithm correcting for patient heterogeneity. The bolus was then fabricated from modeling wax using a computer-controlled milling device. To aid in quality assurance, CT images with the bolus in place were generated and the dose distribution was computed using these images. Results: This technique optimized the dose distribution while minimizing irradiation of normal tissues. The use of a single anterior field eliminated field junction sites. Two patients who benefited from this option are described: one with altered chest wall geometry (congenital pectus excavatum), and one with recurrent disease in the medial chest wall and internal mammary chain (IMC) area. Conclusion: The use of custom 3D electron bolus for PMI is an effective method for optimizing dose delivery. The radiation dose distribution is highly conformal, dose heterogeneity is reduced compared to standard techniques in certain suboptimal settings, and excellent immediate outcome is obtained

  16. Use of the Toric Surgical Marker to Aid in Intraoperative Plaque Placement for the USC Eye Physics Plaques to Treat Uveal Melanoma: A New Surgical Technique.

    Science.gov (United States)

    Berry, Jesse L; Kim, Jonathan W; Jennelle, Richard; Astrahan, Melvin

    2015-09-01

    To describe a new surgical technique for intraoperative placement of Eye Physics (EP) plaques for uveal melanoma using a toric marker. A toric marker is designed for cataract surgery to align the axis of astigmatism; its use was modified in this protocol to mark the axis of suture coordinates as calculated by Plaque Simulator (PS) software. The toric marker can be used to localize suture coordinates, in degrees, during intraoperative plaque placement. Linear marking using the toric marker decreases potential inaccuracies associated with the surgeon estimating 'clock-hours' by dot placement. Use of the toric marker aided surgical placement of EP plaques. The EP planning protocol is now designed to display the suture coordinates either by clock-hours or degrees, per surgeon preference. Future research is necessary to determine whether routine use of the toric marker improves operative efficiency. [Ophthalmic Surg Lasers Imaging Retina. 2015;46:866-870.]. Copyright 2015, SLACK Incorporated.

  17. Muscle optimization techniques impact the magnitude of calculated hip joint contact forces

    NARCIS (Netherlands)

    Wesseling, M.; Derikx, L.C.; de Groote, F.; Bartels, W.; Meyer, C.; Verdonschot, Nicolaas Jacobus Joseph; Jonkers, I.

    2015-01-01

    In musculoskeletal modelling, several optimization techniques are used to calculate muscle forces, which strongly influence resultant hip contact forces (HCF). The goal of this study was to calculate muscle forces using four different optimization techniques, i.e., two different static optimization

  18. Nurse-perceived barriers to effective communication regarding prognosis and optimal end-of-life care for surgical ICU patients: a qualitative exploration.

    Science.gov (United States)

    Aslakson, Rebecca A; Wyskiel, Rhonda; Thornton, Imani; Copley, Christina; Shaffer, Dauryne; Zyra, Marylou; Nelson, Judith; Pronovost, Peter J

    2012-08-01

    Integration of palliative care for intensive care unit (ICU) patients is important but often challenging, especially in surgical ICUs (SICUs), in part because many surgeons equate palliative care with terminal care and failure of restorative care. SICU nurses, who are key front-line clinicians, can provide insights into barriers for delivery of optimal palliative care in their setting. We developed a focus group guide to identify barriers to two key components of palliative care-optimal communication regarding prognosis and optimal end-of-life care-and used the tool to conduct focus groups of nurses providing bedside care in three SICUs at a tertiary care, academic, inner city hospital. Using content analysis technique, responses were organized into thematic domains that were validated by independent observers and a subset of participating nurses. Four focus groups included a total of 32 SICU nurses. They identified 34 barriers to optimal communication regarding prognosis, which were summarized into four domains: logistics, clinician discomfort with discussing prognosis, inadequate skill and training, and fear of conflict. For optimal end-of-life care, the groups identified 24 barriers in four domains: logistics, inability to acknowledge an end-of-life situation, inadequate skill and training, and cultural differences relating to end-of-life care. Nurses providing bedside care in SICUs identify barriers in several domains that may impede optimal discussions of prognoses and end-of-life care for patients with surgical critical illness. Consideration of these perceived barriers and the underlying SICU culture is relevant for designing interventions to improve palliative care in this setting.

  19. Localization techniques for guided surgical excision of non-palpable breast lesions.

    Science.gov (United States)

    Chan, Benjamin K Y; Wiseberg-Firtell, Jill A; Jois, Ramesh H S; Jensen, Katrin; Audisio, Riccardo A

    2015-12-31

    contrast, WGL had fewer postoperative complications to both ROLL (RR 1.18, 95% CI 0.71 to 1.98; 642 participants; four trials) and RSL (RR 1.51, 95% CI 0.75 to 3.03; 305 participants; one trial), although this was also not statistically significant.The overall quality of evidence was good. The main risk of bias amongst included studies consisted of incomplete data sets, selective reporting, and allocation concealment. Interpretation and applicability of this meta-analysis was hindered by the mixed indication of diagnostic versus therapeutic purposes when undertaking WGL, ROLL, or RSL, leading to a high level of mixed pathology in numerous trials. Other limitations include underpowered studies, lack of data in standardized format for meta-analysis, lack of complete data amongst the trials, and absence of long-term data. Owing to a lack of trials in certain localization techniques, we could only draw conclusions about ROLL and RSL versus WGL. There is no clear evidence to support one guided technique for surgically excising a non-palpable breast lesion over another. Results from this Cochrane review support the continued use of WGL as a safe and tested technique that allows for flexibility in selected cases when faced with extensive microcalcification. ROLL and RSL could be offered to patients as a comparable replacement for WGL as they are equally reliable. Other techniques such as IOUS, RCML, and CAL are of academic interest, but recommendation for routine use in the clinical environment and oncological outcomes require further validation. The results of this Cochrane review also stress the need for more fully powered RCTs to evaluate the best technique according to the comprehensive criteria described, with a more consistent and standardized approach in outcome reporting.

  20. Recurrent tricuspid insufficiency: is the surgical repair technique a risk factor?

    Science.gov (United States)

    Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

    2013-01-01

    This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair. In our clinic, 93 patients with functional tricuspid insufficiency underwent surgical tricuspid repair from May 2007 through October 2010. The study was retrospective, and all the data pertaining to the patients were retrieved from hospital records. Functional capacity, recurrent tricuspid insufficiency, and risk factors aggravating the insufficiency were analyzed for each patient. In the medium term (25.4 ± 10.3 mo), the rates of grades 3 and 4 tricuspid insufficiency in the De Vega, modified De Vega, and ring annuloplasty groups were 31%, 23.1%, and 6.1%, respectively. Logistic regression analysis revealed that chronic obstructive pulmonary disease, left ventricular dysfunction (ejection fraction, tricuspid insufficiency. Medium-term survival was 90.6% for the De Vega group, 96.3% for the modified De Vega group, and 97.1% for the ring annuloplasty group. Ring annuloplasty provided the best relief from recurrent tricuspid insufficiency when compared with DeVega annuloplasty. Modified De Vega annuloplasty might be a suitable alternative to ring annuloplasty when rings are not available.

  1. Bilateral posterior tarsal tunnel syndrome caused by accessory flexor digitorum longus; case report and surgical technique.

    Science.gov (United States)

    Schmidt-Hebbel, A; Elgueta, J; Villa, A; Mery, P; Filippi, J

    To present a case report of bilateral posterior tarsal tunnel syndrome (PTTS) caused by an accessory flexor digitorum longus (AFDL), including the surgical technique and a review of the literature. Twenty-nine year old male diagnosed with bilateral PTTS, refractory to conservative management, with 53 points on the preoperative AOFAS score. MR of both ankles showed an AFDL within the tarsal tunnel, in close relationship to the posterior tibial nerve. Bilateral tarsal tunnel decompression and AFDL resection was performed. There were no post-operative complications. At 6 months after surgery, the patient had no pain and had 87 points on the AOFAS score. The PTTS is an entrapment neuropathy of the posterior tibial nerve or one of its terminal branches. A rare cause is the presence of an AFDL, and its resection is associated with good clinical results. Careful scar tissue resection and neurolysis is recommended. Knowing the normal pathway and anatomical variability of the posterior tibial nerve and its branches is essential to avoid iatrogenic injury. In our case report, MR and intraoperative findings identified a bilateral FDLA in close relationship to the common flexor digitorum, an unusual finding, with few reports in current literature. Careful tarsal tunnel decompression and AFDL resection in our patient with bilateral symptomatic PTTS has good clinical results and no complications, particularly when diagnosed and treated early. Copyright © 2015 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Two-Stage Tissue-Expander Breast Reconstruction: A Focus on the Surgical Technique

    Directory of Open Access Journals (Sweden)

    Elisa Bellini

    2017-01-01

    Full Text Available Objective. Breast cancer, the most common malignancy in women, comprises 18% of all female cancers. Mastectomy is an essential intervention to save lives, but it can destroy one’s body image, causing both physical and psychological trauma. Reconstruction is an important step in restoring patient quality of life after the mutilating treatment. Material and Methods. Tissue expanders and implants are now commonly used in breast reconstruction. Autologous reconstruction allows a better aesthetic result; however, many patients prefer implant reconstruction due to the shorter operation time and lack of donor site morbidity. Moreover, this reconstruction strategy is safe and can be performed in patients with multiple health problems. Tissue-expander reconstruction is conventionally performed as a two-stage procedure starting immediately after mammary gland removal. Results. Mastectomy is a destructive but essential intervention for women with breast cancer. Tissue expansion breast reconstruction is a safe, reliable, and efficacious procedure with considerable psychological benefits since it provides a healthy body image. Conclusion. This article focuses on this surgical technique and how to achieve the best reconstruction possible.

  3. Distal fascia lata lengthening: an alternative surgical technique for recalcitrant trochanteric bursitis

    Science.gov (United States)

    Ortega, Javier; García-Rayo, Ramón; Resines, Carlos

    2009-01-01

    This article presents a simple technique for fascia lata lengthening that is less aggressive, can be performed under local anaesthetic with little morbidity and disability, and has excellent results. Eleven patients (13 hips) were enrolled in this study. Mean age was 54.6 years, there was one man and ten women. Outcomes were assessed by using a visual analog pain scale, Harris hip score and Lickert scale (satisfaction). There was a mean follow-up time of 43 months (range 15–84). All patients were scored by the Harris hip scale with a mean improvement from 61 (range 48–77) to 91 (range 76–95) after surgery. The mean visual analogue scale (VAS) score improved from 83 (range 60–99) to 13 (range 0–70). We had 12 of 13 patients reporting a good result. Mean surgical time was 15 min, and only one seroma was reported as a complication. No inpatient management was needed. In conclusion, distal “Z” lengthening of the fascia lata appears to be a good alternative for treatment of this condition. PMID:19214507

  4. Fixation of revision implants is improved by a surgical technique to crack the sclerotic bone rim.

    Science.gov (United States)

    Kold, Søren; Bechtold, Joan E; Mouzin, Olivier; Elmengaard, Brian; Chen, Xinqian; Søballe, Kjeld

    2005-03-01

    Revision joint replacement has poorer outcomes compared with primary joint replacement, and these poor outcomes have been associated with poorer fixation. We investigated a surgical technique done during the revision operation to improve access from the marrow space to the implant interface by locally cracking the sclerotic bone rim that forms during aseptic loosening. Sixteen implants were inserted bilaterally by distal femur articulation of the knee joint of eight dogs, using our controlled experimental model that replicates the revision setting (sclerotic bone rim, dense fibrous tissue, macrophages, elevated cytokines) by pistoning a loaded 6.0-mm implant 500 microm into the distal femur with particulate PE. At 8 weeks, one of two revision procedures was done. Both revision procedures included complete removal of the membrane, scraping, lavaging, and inserting a revision plasma-spray Ti implant. The crack revision procedure also used a splined tool to circumferentially locally perforate the sclerotic bone rim before insertion of an identical revision implant. Superior fixation was achieved with the cracking procedure in this experimental model. Revision implants inserted with the rim cracking procedure had a significantly higher pushout strength (fivefold median increase) and energy to failure (sixfold median increase), compared with the control revision procedure. Additional evaluation is needed of local perforation of sclerotic bone rim as a simple bone-sparing means to improve revision implant fixation and thereby increase revision implant longevity.

  5. Arthroscopic Surgical Technique for an Acute Talar Dome Osteochondral Lesion in a Professional Rugby League Player.

    Science.gov (United States)

    Sullivan, Martin; Fraser, Ethan J; Linklater, James; Harris, Craig; Morgan, Kieran

    2017-06-01

    Talar osteochondral lesions represent challenging clinical entities, particularly in high-demand athletes. Surgical treatment of large lesions often requires a 2-step procedure, or the use of osteotomy in the case of autologous osteochondral transfer, which can delay return to sport. A professional rugby league player underwent surgery for a complex injury to the ankle. A talar osteochondral lesion with a maximal diameter of 15 mm was treated in an arthroscopic fashion using the cartilage taken from the completely displaced osteochondral fragment. Cartilage was cut into chips and combined with bone graft product containing platelet-derived growth factor and a porous collagen scaffold. Autologous cartilage was then reimplanted arthroscopically. The patient was allowed full ankle motion from 2 weeks postoperatively, and weightbearing was commenced at 6 weeks. Follow-up imaging and functional outcomes, including return to sport, were assessed at regular intervals. The patient was able to return to professional rugby league by 23 weeks postoperatively. Magnetic resonance imaging at 16 months postoperatively showed restoration of the subchondral plate and osseous infill. At final follow-up, the patient remained pain free and was playing at preinjury level. This report describes good outcomes using a novel, 1-step cartilage repair technique to treat a large talar osteochondral lesion in a professional athlete. Level V: Expert opinion.

  6. Optimization of Thermal Aspects of Friction Stir Welding – Initial Studies Using a Space Mapping Technique

    DEFF Research Database (Denmark)

    Larsen, Anders Astrup; Bendsøe, Martin P.; Schmidt, Henrik Nikolaj Blicher

    2007-01-01

    The aim of this paper is to optimize a thermal model of a friction stir welding process. The optimization is performed using a space mapping technique in which an analytical model is used along with the FEM model to be optimized. The results are compared to traditional gradient based optimization...

  7. Laparoscopic cystostomy in pigs: Technique and comparison with traditional open cystostomy for surgical stress

    Directory of Open Access Journals (Sweden)

    Hua Zhang

    2014-01-01

    Full Text Available Cystostomy is a common procedure in veterinary surgery. We describe a technique for laparoscopic cystostomy (LC group; n = 7 in Bama miniature pigs and compare the surgical stress induced by this procedure to open cystostomy (OC group; n = 7. A three-portal approach was used for laparoscopic cystostomy. First, we placed 2 simple interrupted sutures between the ventral body wall and urinary bladder. Then, a purse-string suture was placed in the urinary bladder wall, approximately 1 cm cranially to the two sutures. A stab incision was made at the center of the purse-string suture and a 12-F Foley catheter advanced into the urinary bladder; the suture was then pulled tightly and tied. Again, two interrupted sutures were placed 1 cm cranially to the catheter, between the ventral body wall and the bladder, to establish cystopexy. The extracorporeal portion of the catheter was fixed to the skin by a finger-trap suture. Blood samples were collected to measure the white blood cell count and serum concentrations of cortisol, interleukin-6, and C-reactive protein; follow-up laparoscopy was performed 1 month after the surgery. Laparoscopic cystotomy was successfully performed in all the pigs; the mean operating time was 43 ± 5 min. The levels of the stress markers reflected a lower stress response for LC than OC. Thus, LC appears to be better than OC both in terms of technique and physiological responses elicited, and may be more suitable than OC in the creation of experimental animal models for investigations on urinary diseases and those requiring diversion of urine flow.

  8. Pilot study: evaluation of the use of the convergent interview technique in understanding the perception of surgical design and simulation.

    Science.gov (United States)

    Logan, Heather; Wolfaardt, Johan; Boulanger, Pierre; Hodgetts, Bill; Seikaly, Hadi

    2013-06-19

    It is important to understand the perceived value of surgical design and simulation (SDS) amongst surgeons, as this will influence its implementation in clinical settings. The purpose of the present study was to examine the application of the convergent interview technique in the field of surgical design and simulation and evaluate whether the technique would uncover new perceptions of virtual surgical planning (VSP) and medical models not discovered by other qualitative case-based techniques. Five surgeons were asked to participate in the study. Each participant was interviewed following the convergent interview technique. After each interview, the interviewer interpreted the information by seeking agreements and disagreements among the interviewees in order to understand the key concepts in the field of SDS. Fifteen important issues were extracted from the convergent interviews. In general, the convergent interview was an effective technique in collecting information about the perception of clinicians. The study identified three areas where the technique could be improved upon for future studies in the SDS field.

  9. An evaluation of surgical outcome of bilateral cleft lip surgery using a modified Millard′s (Fork Flap technique

    Directory of Open Access Journals (Sweden)

    W L Adeyemo

    2013-01-01

    Full Text Available Background: The central third of the face is distorted by the bilateral cleft of the lip and palate and restoring the normal facial form is one of the primary goals for the reconstructive surgeons. The history of bilateral cleft lip repair has evolved from discarding the premaxilla and prolabium and approximating the lateral lip elements to a definitive lip and primary cleft nasal repair utilising the underlying musculature. The aim of this study was to review surgical outcome of bilateral cleft lip surgery (BCLS done at the Lagos University Teaching Hospital. Materials and Methods: A review of all cases of BCLS done between January 2007 and December 2012 at the Lagos University Teaching Hospital was done. Data analysis included age and sex of patients, type of cleft deformity and type of surgery (primary or secondary and whether the cleft deformity was syndromic and non-syndromic. Techniques of repair, surgical outcome and complications were also recorded. Results: A total of 39 cases of BCLS involving 21 males and 18 females were done during the period. This constituted 10% (39/390 of all cases of cleft surgery done during the period. There were 5 syndromic and 34 non-syndromic cases. Age of patients at time of surgery ranged between 3 months and 32 years. There were 24 bilateral cleft lip and palate deformities and 15 bilateral cleft lip deformities. Thirty-one of the cases were primary surgery, while 8 were secondary (revision surgery. The most common surgical technique employed was modified Fork flap (Millard technique, which was employed in 37 (95% cases. Conclusion: Bilateral cleft lip deformity is a common cleft deformity seen in clinical practice, surgical repair of which can be a challenge to an experienced surgeon. A modified Fork flap technique for repair of bilateral cleft lip is a reliable and versatile technique associated with excellent surgical outcome.

  10. Accelerating orthodontic tooth movement: A new, minimally-invasive corticotomy technique using a 3D-printed surgical template

    Science.gov (United States)

    Giansanti, Matteo

    2016-01-01

    Background A reduction in orthodontic treatment time can be attained using corticotomies. The aggressive nature of corticotomy due to the elevation of muco-periosteal flaps and to the duration of the surgery raised reluctance for its employ among patients and dental community. This study aims to provide detailed information on the design and manufacture of a 3D-printed CAD-CAM (computer-aided design and computer-aided manufacturing) surgical guide which can aid the clinician in achieving a minimally-invasive, flapless corticotomy. Material and Methods An impression of dental arches was created; the models were digitally-acquired using a 3D scanner and saved as STereoLithography ( STL ) files. The patient underwent cone beam computed tomography (CBCT): images of jaws and teeth were transformed into 3D models and saved as an STL file. An acrylic template with the design of a surgical guide was manufactured and scanned. The STLs of jaws, scanned casts, and acrylic templates were matched. 3D modeling software allowed the view of the 3D models from different perspectives and planes with perfect rendering. The 3D model of the acrylic template was transformed into a surgical guide with slots designed to guide, at first, a scalpel blade and then a piezoelectric cutting insert. The 3D STL model of the surgical guide was printed. Results This procedure allowed the manufacturing of a 3D-printed CAD/CAM surgical guide, which overcomes the disadvantages of the corticotomy, removing the need for flap elevation. No discomfort, early surgical complications or unexpected events were observed. Conclusions The effectiveness of this minimally-invasive surgical technique can offer the clinician a valid alternative to other methods currently in use. Key words:Corticotomy, orthodontics, CAD/CAM, minimally invasive, surgical template, 3D printer. PMID:27031067

  11. Optimal fringe angle selection for digital fringe projection technique.

    Science.gov (United States)

    Wang, Yajun; Zhang, Song

    2013-10-10

    Existing digital fringe projection (DFP) systems mainly use either horizontal or vertical fringe patterns for three-dimensional shape measurement. This paper reveals that these two fringe directions are usually not optimal where the phase change is the largest to a given depth variation. We propose a novel and efficient method to determine the optimal fringe angle by projecting a set of horizontal and vertical fringe patterns onto a step-height object and by further analyzing two resultant phase maps. Experiments demonstrate the existence of the optimal angle and the success of the proposed optimal angle determination method.

  12. One-Step Cartilage Repair Technique as a Next Generation of Cell Therapy for Cartilage Defects: Biological Characteristics, Preclinical Application, Surgical Techniques, and Clinical Developments.

    Science.gov (United States)

    Zhang, Chi; Cai, You-Zhi; Lin, Xiang-Jin

    2016-07-01

    To provide a comprehensive overview of the basic science rationale, surgical technique, and clinical outcomes of 1-step cartilage repair technique used as a treatment strategy for cartilage defects. A systematic review was performed in the main medical databases to evaluate the several studies concerning 1-step procedures for cartilage repair. The characteristics of cell-seed scaffolds, behavior of cells seeded into scaffolds, and surgical techniques were also discussed. Clinical outcomes and quality of repaired tissue were assessed using several standardized outcome assessment tools, magnetic resonance imaging scans, and biopsy histology. One-step cartilage repair could be divided into 2 types: chondrocyte-matrix complex (CMC) and autologous matrix-induced chondrogenesis (AMIC), both of which allow a simplified surgical approach. Studies with Level IV evidence have shown that 1-step cartilage repair techniques could significantly relieve symptoms and improve functional assessment (P studies clearly showed hyaline-like cartilage tissue in biopsy tissues by second-look arthroscopy. The 1-step cartilage repair technique, with its potential for effective, homogeneous distribution of chondrocytes and multipotent stem cells on the surface of the cartilage defect, is able to regenerate hyaline-like cartilage tissue, and it could be applied to cartilage repair by arthroscopy. Level IV, systematic review of Level II and IV studies. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  13. Microscope-integrated intraoperative optical coherence tomography-guided small-incision lenticule extraction: New surgical technique.

    Science.gov (United States)

    Sharma, Namrata; Urkude, Jayanand; Chaniyara, Manthan; Titiyal, Jeewan S

    2017-10-01

    We describe the surgical technique of microscope-integrated intraoperative optical coherence tomography (OCT)-guided small-incision lenticule extraction. The technique enables manual tracking of surgical instruments and identification of the desired dissection plane. It also helps discern the relation between the dissector and the intrastromal lenticule. The dissection plane becomes hyperreflective on dissection, ensuring complete separation of the intrastromal lenticule from the overlying and underlying stroma. Inadvertent posterior plane entry, cap-lenticule adhesion, incomplete separation of the lenticule, creation of a false plane, and lenticule remnants may be recognized intraoperatively so corrective steps can be taken immediately. In cases with a hazy overlying cap, microscope-integrated intraoperative OCT enables localization and extraction of the lenticule. The technique is helpful for inexperienced surgeons, especially in cases with low amplitudes of refractive errors, ie, thin lenticules. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  14. Surgical techniques in radiation induced temporal lobe necrosis in nasopharyngeal carcinoma patients.

    Science.gov (United States)

    Alfotih, Gobran Taha Ahmed; Zheng, Mei Guang; Cai, Wang Qing; Xu, Xin Ke; Hu, Zhen; Li, Fang Cheng

    2016-01-01

    Radiation induced brain injury ranges from acute reversible edema to late, irreversible radiation necrosis. Radiation induced temporal lobe necrosis is associated with permanent neurological deficits and occasionally progresses to death. We present our experience with surgery on radiation induced temporal lobe necrosis (RTLN) in nasopharyngeal carcinoma (NPC) patients with special consideration of clinical presentation, surgical technique, and outcomes. This retrospective study includes 12 patients with RTLN treated by the senior author between January 2010 and December 2014. Patients initially sought medical treatment due to headache; other symptoms were hearing loss, visual deterioration, seizure, hemiparesis, vertigo, memory loss and agnosia. A temporal approach through a linear incision was performed for all cases. RTLN was found in one side in 7 patients, and bilaterally in 5. 4 patients underwent resection of necrotic tissue bilaterally and 8 patients on one side. No death occurred in this series of cases. There were no post-operative complications, except 1 patient who developed aseptic meningitis. All 12 patients were free from headache. No seizure occurred in patients with preoperative epilepsy. Other symptoms such as hemiparesis and vertigo improved in all patients. Memory loss, agnosia and hearing loss did not change post-operatively in all cases. The follow-up MR images demonstrated no recurrence of necrotic lesions in all 12 patients. Neurosurgical intervention through a temporal approach with linear incision is warranted in patients with radiation induced temporal lobe necrosis with significant symptoms and signs of increased intracranial pressure, minimum space occupying effect on imaging, or neurological deterioration despite conservative management. Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. Pediatric endocanalicular diode laser dacryocystorhinostomy: results of a minimally invasive surgical technique.

    Science.gov (United States)

    Uysal, Ismail Onder; Ozçimen, Muammer; Yener, Halil Ibrahim; Kal, Ali

    2011-09-01

    The purpose of this study was to evaluate the effectiveness of endocanalicular diode laser dacryocystorhinostomy (DCR), which is a minimally invasive surgical technique, in pediatric patients with congenital nasolacrimal duct obstruction (NLDO). A retrospective study was carried out on patients treated between October 2008 and August 2009 for nasolacrimal duct obstruction with an endocanalicular diode laser procedure. Patients diagnosed as having nasolacrimal duct obstruction were included in this study and an endocanalicular diode laser procedure was performed. The main outcome measures were patients' previous treatments, clinical presentation, operative and postoperative complications, postoperative follow-up and resolution of epiphora. Eighteen children (10 girls, 8 boys) with a mean age of 6.11 ± 2.08 years (range, 4-10) underwent 20 endocanalicular laser DCR operations for congenital NLDO. In all eyes (100%), there was a history of epiphora and chronic dacryocystitis; two (10%) presented with acute dacryocystitis. Previous procedures included probing and irrigation of all eyes (100%) and silicone tube intubation in nine eyes (45%). None of the patients underwent any previous DCR operations. During a mean postoperative follow-up period of 20.50 ± 3.24 months (range, 14-24 months), the anatomical success rate (patency of ostium on nasal endoscopy) was 100%, and the clinical success rate (resolution of epiphora) was 85%. Endocanalicular diode laser DCR is an effective treatment modality for pediatric patients with congenital NLDO that compares favorably with the reported success rates of external and endoscopic endonasal DCR. Moreover, it has an added advantage of shorter operative time, less morbidity and avoidance of overnight admission.

  16. Surgical treatment of gynecomastia with severe ptosis: periareolar incision and dermal double areolar pedicle technique.

    Science.gov (United States)

    Cannistra, Claudio; Piedimonte, Andrea; Albonico, Fiorella

    2009-11-01

    Gynecomastia is a morphostructural impairment of the mammary region in men caused by parenchymal hypertrophy or a cutaneous distortion of breast skin covering or both. The clinical classification introduced by Simon et al. in 1973 ranks gynecomastia in three degrees. Each subtype can be treated with a specific technique. This article describes an alternative surgical procedure for treating gynecomastia with severe ptosis(type III and type IIIb of Simon's classification). Fifty-eight patients were treated for gynecomastia in our Plastic Surgery Unit from 1996 to 2004. The cutaneous excess of periareolar skin is evaluated by a pinching test. A circular periareolar mark is traced corresponding to the cutaneous excess that has to be removed.Initially, liposuction of adipous tissue on the periphery of the mammary region is performed through two cutaneous 3-mm incisions at the 3 o'clock and 9 o'clock positions around the areola. After this, the liposuction incisions are enlarged from 10 o'clock to 8 o'clock and from 2 o'clockto 4 o'clock to create access for the mastectomy. This dissection creates a double dermal areolar pedicle. The new areolar position is fixed with a Benelli round block suture. A resolution of the morphologic deformity without evident scars after hair growth and a correction of the breast deformity has been observed in the 6-month follow-ups conducted for all the patients. We observed that the vascular-nervous net under the areola at 12 o'clock and 6 o'clock is very important, more so than the lateral pedicle, and the conservation of a double vascular-nervous pedicle reduces significantly the risk of areolar necrosis, especially in cases of gynecomastia type III and in cases where there is a high degree of breast malformation such as the tuberous breast.

  17. The modified Pirogoff's amputation in treating diabetic foot infections: surgical technique and case series

    Directory of Open Access Journals (Sweden)

    Aziz Nather

    2014-04-01

    Full Text Available Background: This paper describes the surgical technique of a modified Pirogoff's amputation performed by the senior author and reports the results of this operation in a single surgeon case series for patients with diabetic foot infections. Methods: Six patients with diabetic foot infections were operated on by the National University Hospital (NUH diabetic foot team in Singapore between November 2011 and January 2012. All patients underwent a modified Pirogoff's amputation for diabetic foot infections. Inclusion criteria included the presence of a palpable posterior tibial pulse, ankle brachial index (ABI of more than 0.7, and distal infections not extending proximally beyond the midfoot level. Clinical parameters such as presence of pulses and ABI were recorded. Preoperative blood tests performed included a glycated hemoglobin level, hemoglobin, total white blood cell count, C-reactive protein, erythrocyte sedimentation rate, albumin, and creatinine levels. All patients were subjected to 14 sessions of hyperbaric oxygen therapy postoperatively and were followed up for a minimum of 10 months. Results: All six patients had good wound healing. Tibio-calcaneal arthrodesis of the stump was achieved in all cases by 6 months postoperatively. All patients were able to walk with the prosthesis. Conclusions: The modified Pirogoff's amputation has been found to show good results in carefully selected patients with diabetic foot infections. The selection criteria included a palpable posterior tibial pulse, distal infections not extending proximally beyond the midfoot level, ABI of more than 0.7, hemoglobin level of more than 10 g/dL, and serum albumin level of more than 30 g/L.

  18. [The sural medial perforator flap: Anatomical bases, surgical technique and indications in head and neck reconstruction].

    Science.gov (United States)

    Struk, S; Schaff, J-B; Qassemyar, Q

    2018-04-01

    The medial sural artery perforator (MSAP) flap is defined as a thin cutaneo-adipose perforator flap harvested on the medial aspect of the leg. The aims of this study were to describe the anatomical basis as well as the surgical technique and discuss the indications in head and neck reconstructive surgery. We harvested 10 MSAP flap on 5 fresh cadavers. For each case, the number and the location of the perforators were recorded. For each flap, the length of pedicle, the diameter of source vessels and the thickness of the flap were studied. Finally, we performed a clinical application of a MSAP flap. A total of 23 perforators with a diameter superior than 1mm were dissected on 10 legs. The medial sural artery provided between 1 and 4 musculocutaneous perforators. Perforators were located in average at 10.3cm±2cm from the popliteal fossa and at 3.6cm±1cm from the median line of the calf. The mean pedicle length was 12.1cm±2.5cm. At its origin, the source artery diameter was 1.8mm±0.25mm and source veins diameters were 2.45mm±0.9mm in average. There was no complication in our clinical application. This study confirms the reliability of previous anatomical descriptions of the medial sural artery perforator flap. This flap was reported as thin and particularly adapted for oral cavity reconstruction and for facial or limb resurfacing. Sequelae might be reduced as compared to those of the radial forearm flap with comparable results. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. A novel single-step surgical technique for vestibular deepening using laser in conjunction with periodontal flap surgery

    Directory of Open Access Journals (Sweden)

    Ashu Bhardwaj

    2016-01-01

    Full Text Available Moderate-to-severe chronic periodontitis results in clinical loss of attachment, reduced width of attached gingiva (AG, periodontal pockets beyond mucogingival junction (MGJ, gingival recession, loss of alveolar bone, and decreased vestibular depth (VD. The encroachment of frenal and muscle attachments on marginal gingiva increases the rate of progression of periodontal pockets, prevents healing, and causes their recurrence after therapy. Loss of VD and AG associated with continuous progression of pocket formation and bone loss requires two-stage surgical procedures. In this article, one-stage surgical procedure is being described for the first time, to treat the periodontal pockets extending beyond the MGJ by periodontal flap surgery along with vestibular deepening with diode laser to increase the AG. One-step surgical technique is illustrated whereby pocket therapy with reconstruction of lost periodontal tissues can be done along with gingival augmentation by vestibular deepening.

  20. Para-axillary subcutaneous endoscopic approach in torticollis: tips and tricks in the surgical technique.

    Science.gov (United States)

    Tokar, Baran; Karacay, Safak; Arda, Surhan; Alici, Umut

    2015-04-01

    An obvious scar on the neck may appear following the open surgery for congenital muscular torticollis (CMT). The cosmetic result may displease the patient and the family. In this study, we describe a minimally invasive technique, para-axillary subcutaneous endoscopic approach (PASEA) in CMT. A total of 11 children (seven girls and four boys with the age range between 1 and 15 years) were operated for torticollis by PASEA. All patients had facial asymmetry and head and neck postural abnormality. Following an incision at the ipsilateral para-axillary region, a subcutaneous cavernous working space is formed toward sternocleidomastoid (SCM) muscle. The muscle and fascia are cut by cautery under endoscopic vision. The patients had postoperative 2nd-week and 3rd-month visits. The incision scar, inspection, and palpation findings of the region, head posture, and shoulder position of the affected side were considered in evaluation of the cosmetic outcome. Preoperative and postoperative range of motion of the head and neck were compared for functional outcome. We preferred single incision surgery in our last two patients; the rest had double para-axillary incision for port insertion. Incomplete transection of the muscle was not observed. There was no serious complication. Postoperatively, head posture and shoulder elevation were corrected significantly. Range of motion of the head was improved. Postoperatively, all the patients had rotation capacity with more than 30 degrees. The range of postoperative flexion and extension movements was between 45 and 60 degrees. The open surgery techniques of CMT causes visible lifelong incision scar on the neck. PASEA leaves a cosmetically hidden scar in the axillary region. A single incision surgery is also possible. A well-formed cavernous working space is needed. External manual palpation, delicate dissection, and cutting of SCM muscle with cautery are the important components of the procedure. Surgeons having experience in pediatric

  1. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis

    OpenAIRE

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-01-01

    Background Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM...

  2. Complicated problem solution techniques in optimal parameter searching

    International Nuclear Information System (INIS)

    Gergel', V.P.; Grishagin, V.A.; Rogatneva, E.A.; Strongin, R.G.; Vysotskaya, I.N.; Kukhtin, V.V.

    1992-01-01

    An algorithm is presented of a global search for numerical solution of multidimentional multiextremal multicriteria optimization problems with complicated constraints. A boundedness of object characteristic changes is assumed at restricted changes of its parameters (Lipschitz condition). The algorithm was realized as a computer code. The algorithm was realized as a computer code. The programme was used to solve in practice the different applied optimization problems. 10 refs.; 3 figs

  3. Advanced Gradient Based Optimization Techniques Applied on Sheet Metal Forming

    International Nuclear Information System (INIS)

    Endelt, Benny; Nielsen, Karl Brian

    2005-01-01

    The computational-costs for finite element simulations of general sheet metal forming processes are considerable, especially measured in time. In combination with optimization, the performance of the optimization algorithm is crucial for the overall performance of the system, i.e. the optimization algorithm should gain as much information about the system in each iteration as possible. Least-square formulation of the object function is widely applied for solution of inverse problems, due to the superior performance of this formulation.In this work focus will be on small problems which are defined as problems with less than 1000 design parameters; as the majority of real life optimization and inverse problems, represented in literature, can be characterized as small problems, typically with less than 20 design parameters.We will show that the least square formulation is well suited for two classes of inverse problems; identification of constitutive parameters and process optimization.The scalability and robustness of the approach are illustrated through a number of process optimizations and inverse material characterization problems; tube hydro forming, two step hydro forming, flexible aluminum tubes, inverse identification of material parameters

  4. A comprehensive review of prostate cancer brachytherapy: defining an optimal technique

    International Nuclear Information System (INIS)

    Vicini, Frank A.; Kini, Vijay R.; Edmundson, Gregory B.S.; Gustafson, Gary S.; Stromberg, Jannifer; Martinez, Alvaro

    1999-01-01

    Purpose: A comprehensive review of prostate cancer brachytherapy literature was performed to determine if an optimal method of implantation could be identified, and to compare and contrast techniques currently in use. Methods and Materials: A MEDLINE search was conducted to obtain all articles in the English language on prostate cancer brachytherapy from 1985 through 1998. Articles were reviewed and grouped to determine the primary technique of implantation, the method or philosophy of source placement and/or dose specification, the technique to evaluate implant quality, overall treatment results (based upon pretreatment prostate specific antigen, (PSA), and biochemical control) and clinical, pathological or biochemical outcome based upon implant quality. Results: A total of 178 articles were identified in the MEDLINE database. Of these, 53 studies discussed evaluable techniques of implantation and were used for this analysis. Of these studies, 52% used preoperative ultrasound to determine the target volume to be implanted, 16% used preoperative computerized tomography (CT) scans, and 18% placed seeds with an open surgical technique. An additional 11% of studies placed seeds or needles under ultrasound guidance using interactive real-time dosimetry. The number and distribution of radioactive sources to be implanted or the method used to prescribe dose was determined using nomograms in 27% of studies, a least squares optimization technique in 11%, or not stated in 35%. In the remaining 26%, sources were described as either uniformly, differentially, or peripherally placed in the gland. To evaluate implant quality, 28% of studies calculated some type of dose-volume histogram, 21% calculated the matched peripheral dose, 19% the minimum peripheral dose, 14% used some type of CT-based qualitative review and, in 18% of studies, no implant quality evaluation was mentioned. Six studies correlated outcome with implant dose. One study showed an association of implant dose

  5. Surgical extrusion: A reliable technique for saving compromised teeth. A 5-years follow-up case report

    Directory of Open Access Journals (Sweden)

    Jenner Argueta

    2018-06-01

    Full Text Available Aim: To present a long term follow up clinical case in which a compromised anterior tooth was saved by a surgical extrusion procedure. Summary: Although different techniques have been suggested for clinical crown lengthening in the anterior zone, some of them have limitations in terms of aesthetics and procedural requirements. The current case report demonstrates how a simplified surgical extrusion procedure was successfully performed for saving a severely damaged anterior tooth; furthermore, it is possible to apply the technique described in this case using minimum and simple armamentarium like a scalpel, elevators, forceps and splinting flexible cord. Key-learning points: Saving severely compromised anterior teeth is possible by applying surgical extrusion techniques when crown-root ratio allows it. Risk of root resorption or ankylosis is minimum. Riassunto: Obiettivo: Presentare un caso clinico con controllo a 5 anni in cui un dente anteriore compromesso è stato recuperato con una procedura di estrusione chirurgica. Riassunto: Sebbene siano state suggerite diverse tecniche per l’allungamento della corona clinica nella zona anteriore, alcune di esse presentano limitazioni in termini di estetica e competenza nelle procedure. Il presente case report dimostra come una procedura di estrusione chirurgica semplificata sia stata eseguita con successo per salvare un dente anteriore gravemente danneggiato. Va sottolineato che la tecnica descritta in questo caso può essere portata a termine utilizzando un armamentario minimo e molto semplice come un bisturi, leve, pinze e uno splintaggio flessibile. Key learning points: E’ possibile salvare elementi dentari gravemente compromessi applicando tecniche di estrusione chirurgica quando il rapporto corona-radice lo consente. Il rischio di riassorbimento della radice o anchilosi è minimo. Keywords: Crown fracture, Crown lengthening, Surgical extrusion, Surgical repositioning, Biologic width, Parole

  6. Machine learning techniques for optical communication system optimization

    DEFF Research Database (Denmark)

    Zibar, Darko; Wass, Jesper; Thrane, Jakob

    In this paper, machine learning techniques relevant to optical communication are presented and discussed. The focus is on applying machine learning tools to optical performance monitoring and performance prediction.......In this paper, machine learning techniques relevant to optical communication are presented and discussed. The focus is on applying machine learning tools to optical performance monitoring and performance prediction....

  7. Optimal Technique for Abdominal Fascial Closure in Liver Transplant Patients

    Directory of Open Access Journals (Sweden)

    Unal Aydin

    2010-01-01

    Conclusion: Our results indicate that the novel technique used in this study contributed to overcoming early and late postoperative complications associated with closure of the abdominal fascia in liver transplant patients. In addition, this new technique has proven to be easily applicable, faster, safer and efficient in these patients; it is also potentially useful for conventional surgery.

  8. The Cost-Effectiveness of Conventional Discectomy Compared to Other Surgical Techniques for Lumbar Disk Herniation. A Systematic Review

    DEFF Research Database (Denmark)

    Thorsen, May Tone; Ødegaard-Olsen, Øystein; Leboeuf-Yde, Charlotte

    2018-01-01

    Background: The current study reviews the literature on the cost-effectiveness of conventional diskectomy compared to other surgical techniques, by assessing studies with economical evaluation and studies using proxy measures of cost-effectiveness. Methods: In April 2016, a comprehensive search w...... studies. The available evidence, however, suggests that any cost-effectiveness difference between conventional diskectomy and the alternatives is unlikely to be great.......Background: The current study reviews the literature on the cost-effectiveness of conventional diskectomy compared to other surgical techniques, by assessing studies with economical evaluation and studies using proxy measures of cost-effectiveness. Methods: In April 2016, a comprehensive search......-four articles were included in the review, 9 retrieved from the original search, and an additional 15 from reference lists. Four studies included an economical evaluation and 20 reported proxy measures of cost-effectiveness. The quality of studies varied considerably and results were ambiguous; the four...

  9. "Two-step" technique with OsiriXTM to evaluate feasibility of C2 pedicle for surgical fixation

    Directory of Open Access Journals (Sweden)

    Luis Miguel Sousa Marques

    2016-01-01

    Full Text Available Background: Surgical treatment of craniovertebral junction pathology has evolved considerably in recent decades with the implementation of short atlanto-axial fixation techniques, notwhithstanding increasing neurovascular risks. Also, there is strong evidence that fixation of C2 anatomical pedicle has the best biomechanical profile of the entire cervical spine. However, it is often difficult and misleading, to evaluate anatomical bony and vascular anomalies using the three orthogonal planes (axial, coronal, and sagittal of CT. Objectives: The authors describe an innovative and simple technique to evaluate the feasibility of C2 pedicle for surgical screw fixation using preoperative planning with the free DICOM (Digital Imaging and Communications in Medicine software OsiriX TM . Materials and Methods: The authors report the applicatin of this novel technique in 5 cases (3 traumatic, 1 Os Odontoideum, and 1 complex congenital malformation collected from our general case series of the Department in the last 5 years. Results: In this "proof of concept" study, the pre-operative analysis with the "two-step" tecnique was detrimental for choosing the surgical tecnique. Detailed post-operative analysis confirmed correct position of C2 screws without cortical breach. There were no complications or mortality reported. Conclusion: This "two-step" technique is an easy and reliable way to determine the feasibility of C2 pedicle for surgical fixation. The detailed tridimensional radiological preoperative evaluation of craniovertebral junction anatomy is critical to the sucess and safety of this surgeries, and can avoid, to certain degree, expensive intra-operative tridimensional imaging facilities.

  10. Clinical experience with a C-section surgical technique in patients with morbid obesity: a case series

    Directory of Open Access Journals (Sweden)

    Mayra Elena Hernández Carrazco

    2014-07-01

    Full Text Available Obesity is a public health challenge that has crossed into the area of reproductive health. An obese pregnant woman has multiple complications before, during, and after pregnancy. Likewise, cesarean section is more difficult and has slower recovery times in this group of patients. This paper proposes a surgical technique adapted to the morbidly obese pregnant patient that aims to reduce cesarean section complications

  11. Development of an adhesive surgical ward round checklist: a technique to improve patient safety.

    LENUS (Irish Health Repository)

    Dhillon, P

    2012-02-01

    Checklists have been shown to improve patient outcomes. Checklist use is seen in the pre-operative to post-operative phases of the patient pathway. An adhesive checklist was developed for ward rounds due to the positive impact it could have on improving patient safety. Over an eight day period data were collected from five consultant-led teams that were randomly selected from the surgical department and divided into sticker groups and control groups. Across the board percentage adherence to the Good Surgical Practice Guidelines (GSPG) was markedly higher in the sticker study group, 1186 (91%) in comparison with the control group 718 (55%). There was significant improvement of documentation across all areas measured. An adhesive checklist for ward round note taking is a simple and cost-effective way to improve documentation, communication, hand-over, and patient safety. Successfully implemented in a tertiary level centre in Dublin, Ireland it is easily transferable to other surgical departments globally.

  12. Optimization Techniques for Dimensionally Truncated Sparse Grids on Heterogeneous Systems

    KAUST Repository

    Deftu, A.; Murarasu, A.

    2013-01-01

    and especially the similarities between our optimization strategies for the two architectures. With regard to our test case for which achieving high speedups is a "must" for real-time visualization, we report a speedup of up to 6.2x times compared to the state

  13. An improved technique for the prediction of optimal image resolution ...

    African Journals Online (AJOL)

    Past studies to predict optimal image resolution required for generating spatial information for savannah ecosystems have yielded different outcomes, hence providing a knowledge gap that was investigated in the present study. The postulation, for the present study, was that by graphically solving two simultaneous ...

  14. Optimal Component Lumping: problem formulation and solution techniques

    DEFF Research Database (Denmark)

    Lin, Bao; Leibovici, Claude F.; Jørgensen, Sten Bay

    2008-01-01

    This paper presents a systematic method for optimal lumping of a large number of components in order to minimize the loss of information. In principle, a rigorous composition-based model is preferable to describe a system accurately. However, computational intensity and numerical issues restrict ...

  15. Optimization of an embedded rail structure using a numerical technique

    NARCIS (Netherlands)

    Markine, V.L.; De Man, A.P.; Esveld, C.

    2000-01-01

    This paper presents several steps of a procedure for design of a railway track aiming at the development of optimal track structures under various predefined service and environmental conditions. The structural behavior of the track is analyzed using a finite element model in which the track and a

  16. Nuclear-fuel-cycle optimization: methods and modelling techniques

    International Nuclear Information System (INIS)

    Silvennoinen, P.

    1982-01-01

    This book present methods applicable to analyzing fuel-cycle logistics and optimization as well as in evaluating the economics of different reactor strategies. After an introduction to the phases of a fuel cycle, uranium cost trends are assessed in a global perspective. Subsequent chapters deal with the fuel-cycle problems faced by a power utility. The fuel-cycle models cover the entire cycle from the supply of uranium to the disposition of spent fuel. The chapter headings are: Nuclear Fuel Cycle, Uranium Supply and Demand, Basic Model of the LWR (light water reactor) Fuel Cycle, Resolution of Uncertainties, Assessment of Proliferation Risks, Multigoal Optimization, Generalized Fuel-Cycle Models, Reactor Strategy Calculations, and Interface with Energy Strategies. 47 references, 34 figures, 25 tables

  17. Purchasing and inventory management techniques for optimizing inventory investment

    International Nuclear Information System (INIS)

    McFarlane, I.; Gehshan, T.

    1993-01-01

    In an effort to reduce operations and maintenance costs among nuclear plants, many utilities are taking a closer look at their inventory investment. Various approaches for inventory reduction have been used and discussed, but these approaches are often limited to an inventory management perspective. Interaction with purchasing and planning personnel to reduce inventory investment is a necessity in utility efforts to become more cost competitive. This paper addresses the activities that purchasing and inventory management personnel should conduct in an effort to optimize inventory investment while maintaining service-level goals. Other functions within a materials management organization, such as the warehousing and investment recovery functions, can contribute to optimizing inventory investment. However, these are not addressed in this paper because their contributions often come after inventory management and purchasing decisions have been made

  18. Optimal fuel loading pattern design using artificial intelligence techniques

    International Nuclear Information System (INIS)

    Kim, Han Gon; Chang, Soon Heung; Lee, Byung Ho

    1993-01-01

    The Optimal Fuel Shuffling System (OFSS) is developed for optimal design of PWR fuel loading pattern. OFSS is a hybrid system that a rule based system, a fuzzy logic, and an artificial neural network are connected each other. The rule based system classifies loading patterns into two classes using several heuristic rules and a fuzzy rule. A fuzzy rule is introduced to achieve more effective and fast searching. Its membership function is automatically updated in accordance with the prediction results. The artificial neural network predicts core parameters for the patterns generated from the rule based system. The back-propagation network is used for fast prediction of core parameters. The artificial neural network and the fuzzy logic can be used as the tool for improvement of existing algorithm's capabilities. OFSS was demonstrated and validated for cycle 1 of Kori unit 1 PWR. (Author)

  19. New diagnostic techniques in staging in the surgical treatment of cutaneous malignant melanoma

    NARCIS (Netherlands)

    Cobben, DCP; Koopal, S; Tiebosch, ATMG; Jager, PL; Elsinga, PH; Wobbes, T; Hoekstra, HJ

    2002-01-01

    The emphasis of the research on the surgical treatment of melanoma has been on the resection margins, the role of elective lymph node dissection. in high risk patients and the value of adjuvant regional treatment with hyperthermic isolated lymph perfusion with melphalan. Parallel to this research,

  20. Journal of Surgical Technique and Case Report - Vol 2, No 1 (2010)

    African Journals Online (AJOL)

    Mayer-Rokitansky-Kuster-Hauser syndrome: Surgical management of two cases · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. L.A Mungadi, Y Ahmad, G.H Yunusa, N.P Agwu, S Ismail, 39-43. http://dx.doi.org/10.4103/2006-8808.63725 ...

  1. Intelligent Heuristic Techniques for the Optimization of the Transshipment and Storage Operations at Maritime Container Terminals

    Directory of Open Access Journals (Sweden)

    Christopher Expósito-Izquierdo

    2017-02-01

    Full Text Available This paper summarizes the main contributions of the Ph.D. thesis of Christopher Exp\\'osito-Izquierdo. This thesis seeks to develop a wide set of intelligent heuristic and meta-heuristic algorithms aimed at solving some of the most highlighted optimization problems associated with the transshipment and storage of containers at conventional maritime container terminals. Under the premise that no optimization technique can have a better performance than any other technique under all possible assumptions, the main point of interest in the domain of maritime logistics is to propose optimization techniques superior in terms of effectiveness and computational efficiency to previous proposals found in the scientific literature when solving individual optimization problems under realistic scenarios. Simultaneously, these optimization techniques should be enough competitive to be potentially implemented in practice. }}

  2. A Novel Surgical Technique for Fixation of Recurrent Acromioclavicular Dislocations: AC Dog Bone Technique in Combination with Autogenous Semitendinosus Tendon Graft

    Directory of Open Access Journals (Sweden)

    Patrick Holweg

    2017-01-01

    Full Text Available Various surgical techniques have been described for the fixation of acromioclavicular (AC dislocations. However, recurrent dislocation is one of the main complications associated with the majority of these techniques. We report a case of postoperative AC joint redislocation. In order to overcome recurrent dislocation after revision surgery, a reconstruction of the conoid and trapezoid ligament with the use of a free tendon graft in combination with a FiberTape was provided within a novel surgical technique. After 12 months, the patient was very satisfied with the functional outcome. The patient achieved excellent results in the Constant (98 points, SPADI (0 points, and QuickDASH score (0 points. The described technique results in an anatomic reconstruction of the AC joint. The nonrigid nature of the intervention seems to restore the normal arthrokinematics by reconstructing the coracoclavicular ligaments with an autograft which is then protected by the AC Dog Bone artificial ligaments during the healing period. The arthroscopic approach to the AC joint with minimal exposure reduces the risks and complications of the intervention. This is the first case in literature that utilizes the artificial dog bone ligament securing the autograft in an anatomic AC reconstruction.

  3. Optimization of connection techniques for multipoint satellite videoconference

    Science.gov (United States)

    Perrone, A.; Puccio, A.; Tirro, S.

    1985-12-01

    Videoconferencing is increasingly considered a convenient substitute for business travels, and satellites will remain for a long time the most convenient means for quick network implementation. The paper gives indications about the most promising connection and demand assignment techniques, and defines a possible protocol for information exchange among involved entities.

  4. Optimizing Nuclear Reactor Operation Using Soft Computing Techniques

    NARCIS (Netherlands)

    Entzinger, J.O.; Ruan, D.; Kahraman, Cengiz

    2006-01-01

    The strict safety regulations for nuclear reactor control make it di±cult to implement new control techniques such as fuzzy logic control (FLC). FLC however, can provide very desirable advantages over classical control, like robustness, adaptation and the capability to include human experience into

  5. Inferior Alveolar Nerve Lateralization and Transposition for Dental Implant Placement. Part I: a Systematic Review of Surgical Techniques

    Directory of Open Access Journals (Sweden)

    Boris Abayev

    2015-03-01

    Full Text Available Objectives: The purpose of this first part of a two-part series was to review the literature concerning the indications, contraindications, advantages, disadvantages and surgical techniques of the lateralization and transposition of the inferior alveolar nerve, followed by the placement of an implant in an edentulous atrophic posterior mandible. Material and Methods: A comprehensive review of the current literature was conducted according to the PRISMA guidelines by accessing the NCBI PubMed and PMC database, academic sites and books. The articles were searched from January 1997 to July 2014 and comprised English-language articles that included adult patients between 18 and 80 years old with minimal residual bone above the mandibular canal who had undergone inferior alveolar nerve (IAN repositioning with a minimum 6 months of follow-up. Results: A total of 16 studies were included in this review. Nine were related to IAN transposition, 4 to IAN lateralization and 3 to both transposition and lateralization. Implant treatment results and complications were presented. Conclusions: Inferior alveolar nerve lateralization and transposition in combination with the installation of dental implants is sometimes the only possible procedure to help patients to obtain a fixed prosthesis, in edentulous atrophic posterior mandibles. With careful pre-operative surgical and prosthetic planning, imaging, and extremely precise surgical technique, this procedure can be successfully used for implant placement in edentulous posterior mandibular segments.

  6. Decomposition based parallel processing technique for efficient collaborative optimization

    International Nuclear Information System (INIS)

    Park, Hyung Wook; Kim, Sung Chan; Kim, Min Soo; Choi, Dong Hoon

    2000-01-01

    In practical design studies, most of designers solve multidisciplinary problems with complex design structure. These multidisciplinary problems have hundreds of analysis and thousands of variables. The sequence of process to solve these problems affects the speed of total design cycle. Thus it is very important for designer to reorder original design processes to minimize total cost and time. This is accomplished by decomposing large multidisciplinary problem into several MultiDisciplinary Analysis SubSystem (MDASS) and processing it in parallel. This paper proposes new strategy for parallel decomposition of multidisciplinary problem to raise design efficiency by using genetic algorithm and shows the relationship between decomposition and Multidisciplinary Design Optimization(MDO) methodology

  7. Electric power systems advanced forecasting techniques and optimal generation scheduling

    CERN Document Server

    Catalão, João P S

    2012-01-01

    Overview of Electric Power Generation SystemsCláudio MonteiroUncertainty and Risk in Generation SchedulingRabih A. JabrShort-Term Load ForecastingAlexandre P. Alves da Silva and Vitor H. FerreiraShort-Term Electricity Price ForecastingNima AmjadyShort-Term Wind Power ForecastingGregor Giebel and Michael DenhardPrice-Based Scheduling for GencosGovinda B. Shrestha and Songbo QiaoOptimal Self-Schedule of a Hydro Producer under UncertaintyF. Javier Díaz and Javie

  8. An optimized staining technique for the detection of Gram positive and Gram negative bacteria within tissue.

    Science.gov (United States)

    Becerra, Sandra C; Roy, Daniel C; Sanchez, Carlos J; Christy, Robert J; Burmeister, David M

    2016-04-12

    Bacterial infections are a common clinical problem in both acute and chronic wounds. With growing concerns over antibiotic resistance, treatment of bacterial infections should only occur after positive diagnosis. Currently, diagnosis is delayed due to lengthy culturing methods which may also fail to identify the presence of bacteria. While newer costly bacterial identification methods are being explored, a simple and inexpensive diagnostic tool would aid in immediate and accurate treatments for bacterial infections. Histologically, hematoxylin and eosin (H&E) and Gram stains have been employed, but are far from optimal when analyzing tissue samples due to non-specific staining. The goal of the current study was to develop a modification of the Gram stain that enhances the contrast between bacteria and host tissue. A modified Gram stain was developed and tested as an alternative to Gram stain that improves the contrast between Gram positive bacteria, Gram negative bacteria and host tissue. Initially, clinically relevant strains of Pseudomonas aeruginosa and Staphylococcus aureus were visualized in vitro and in biopsies of infected, porcine burns using routine Gram stain, and immunohistochemistry techniques involving bacterial strain-specific fluorescent antibodies as validation tools. H&E and Gram stain of serial biopsy sections were then compared to a modification of the Gram stain incorporating a counterstain that highlights collagen found in tissue. The modified Gram stain clearly identified both Gram positive and Gram negative bacteria, and when compared to H&E or Gram stain alone provided excellent contrast between bacteria and non-viable burn eschar. Moreover, when applied to surgical biopsies from patients that underwent burn debridement this technique was able to clearly detect bacterial morphology within host tissue. We describe a modification of the Gram stain that provides improved contrast of Gram positive and Gram negative microorganisms within host

  9. Technique of Antireflux Procedure without Creating Submucosal Tunnel for Surgical Correction of Vesicoureteric Reflux during Bladder Closure in Exstrophy.

    Science.gov (United States)

    Sunil, Kanoujia; Gupta, Archika; Chaubey, Digamber; Pandey, Anand; Kureel, Shiv Narain; Verma, Ajay Kumar

    2018-01-01

    To report the clinical application of the new surgical technique of antireflux procedure without creating submucosal tunnel for surgical correction of vesicoureteric reflux during bladder closure in exstrophy. Based on the report of published experimental technique, the procedure was clinically executed in seven patients of classic exstrophy bladder with small bladder plate with polyps, where the creation of submucosal tunnel was not possible, in last 18 months. Ureters were mobilized. A rectangular patch of bladder mucosa at trigone was removed exposing the detrusor. Mobilized urteres were advanced, crossed and anchored to exposed detrusor parallel to each other. Reconstruction included bladder and epispadias repair with abdominal wall closure. The outcome was measured with the assessment of complications, abolition of reflux on cystogram and upper tract status. At 3-month follow-up cystogram, reflux was absent in all. Follow-up ultrasound revealed mild dilatation of pelvis and ureter in one. The technique of extra-mucosal ureteric reimplantation without the creation of submucosal tunnel is simple to execute without risk and complications and effectively provides an antireflux mechanism for the preservation of upper tract in bladder exstrophy. With the use of this technique, reflux can be prevented since the very beginning of exstrophy reconstruction.

  10. Robotic-assisted partial nephrectomy: surgical technique using a 3-arm approach and sliding-clip renorrhaphy

    Directory of Open Access Journals (Sweden)

    Jose M. Cabello

    2009-04-01

    Full Text Available INTRODUCTION: For the treatment of renal tumors, minimally invasive nephron-sparing surgery has become increasingly performed due to proven efficiency and excellent functional and oncological outcomes. The introduction of robotics into urologic laparoscopic surgery has allowed surgeons to perform challenging procedures in a reliable and reproducible manner. We present our surgical technique for robotic assisted partial nephrectomy (RPN using a 3-arm approach, including a sliding-clip renorrhaphy. MATERIAL AND METHODS: Our RPN technique is presented which describes the trocar positioning, hilar dissection, tumor identification using intraoperative ultrasound for margin determination, selective vascular clamping, tumor resection, and reconstruction using a sliding-clip technique. CONCLUSION: RPN using a sliding-clip renorrhaphy is a valid and reproducible surgical technique that reduces the challenge of the procedure by taking advantage of the enhanced visualization and control afforded by the robot. The renorrhaphy described is performed under complete control of the console surgeon, and has demonstrated a reduction in the warm ischemia times in our series.

  11. The management of thoracic inlet syndrome associated with Hurler's syndrome: a novel surgical technique.

    LENUS (Irish Health Repository)

    Ahsan, Rauf M

    2012-02-01

    A 21-year-old male developed significant swelling of his tongue after a respiratory arrest. The patient had a history of Hurler\\'s syndrome. Magnetic resonance imaging (MRI) angiogram delineated that the swelling was due to compression of his internal jugular veins at the level of the first rib, resulting in thoracic inlet obstruction. The standard surgical treatment of thoracic inlet obstruction was not suitable in this patient\\'s case due to his short thick neck and his characteristic Hurler\\'s syndrome body habitus. Therefore, a novel surgical strategy was used to decompress his head and neck vessels. The manubrium was widened using an iliac crest bone graft, stabilised using internal fixation plates and reconstructed with a pectoral muscle flap.

  12. Duodenum preserving pancreatectomy in chronic pancreatitis: Design of a randomized controlled trial comparing two surgical techniques [ISRCTN50638764

    Directory of Open Access Journals (Sweden)

    Reidel Margot A

    2006-05-01

    Full Text Available Abstract Background Chronic pancreatitis is an inflammatory disease which is characterized by an irreversible conversion of pancreatic parenchyma to fibrous tissue. Beside obstructive jaundice and pseudocyst formation, about half of the patients need surgical intervention due to untreatable chronic pain during the course of the disease. In most of the patients with chronic pancreatitis, the head of the pancreas is the trigger of the chronic inflammatory process. Therefore, resection of pancreatic head tissue must be the central part of any surgical intervention. However, it is unclear to which extent the surgical procedure must be radical in order to obtain a favourable outcome for the patients. Design A single centre randomized controlled, superiority trial to compare two techniques of duodenum preserving pancreatic head resection. Sample size: 65 patients will be included and randomized intraoperatively. Eligibility criteria: All patients with chronic pancreatitis and indication for surgical resection and signed informed consent. Cumulative primary endpoint (hierarchical model: duration of surgical procedure, quality of life after one year, duration of intensive care unit stay, duration of hospital stay. Reference treatment: Resection of the pancreatic head with dissection of the pancreas from the portal vein and transsection of the gland (Beger procedure. Intervention: Partial Resection of the pancreatic head without transsection of the organ and visualization of the portal vein (Berne procedure. Duration: September 2003-October 2007. Organisation/responsibility The trial is conducted in compliance with the protocol and in accordance with the moral, ethical, regulatory and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989 and the Good Clinical Practice guideline (GCP. The Center for Clinical Studies of the Department of Surgery Heidelberg is responsible for planning, conducting and final

  13. Efficiency Optimization by Considering the High Voltage Flyback Transformer Parasitics using an Automatic Winding Layout Technique

    DEFF Research Database (Denmark)

    Thummala, Prasanth; Schneider, Henrik; Zhang, Zhe

    2015-01-01

    .The energy efficiency is optimized using a proposed new automatic winding layout (AWL) technique and a comprehensive loss model.The AWL technique generates a large number of transformer winding layouts.The transformer parasitics such as dc resistance, leakage inductance and self-capacitance are calculated...... for each winding layout.An optimization technique is formulated to minimize the sum of energy losses during charge and discharge operations.The efficiency and energy loss distribution results from the optimization routine provide a deep insight into the high voltage transformer designand its impact...

  14. Visualization and simulation techniques for surgical simulators using actual patient's data.

    Science.gov (United States)

    Radetzky, Arne; Nürnberger, Andreas

    2002-11-01

    Because of the increasing complexity of surgical interventions research in surgical simulation became more and more important over the last years. However, the simulation of tissue deformation is still a challenging problem, mainly due to the short response times that are required for real-time interaction. The demands to hard and software are even larger if not only the modeled human anatomy is used but the anatomy of actual patients. This is required if the surgical simulator should be used as training medium for expert surgeons rather than students. In this article, suitable visualization and simulation methods for surgical simulation utilizing actual patient's datasets are described. Therefore, the advantages and disadvantages of direct and indirect volume rendering for the visualization are discussed and a neuro-fuzzy system is described, which can be used for the simulation of interactive tissue deformations. The neuro-fuzzy system makes it possible to define the deformation behavior based on a linguistic description of the tissue characteristics or to learn the dynamics by using measured data of real tissue. Furthermore, a simulator for minimally-invasive neurosurgical interventions is presented that utilizes the described visualization and simulation methods. The structure of the simulator is described in detail and the results of a system evaluation by an experienced neurosurgeon--a quantitative comparison between different methods of virtual endoscopy as well as a comparison between real brain images and virtual endoscopies--are given. The evaluation proved that the simulator provides a higher realism of the visualization and simulation then other currently available simulators. Copyright 2002 Elsevier Science B.V.

  15. Robotic-assisted transperitoneal nephron-sparing surgery for small renal masses with associated surgical procedures: surgical technique and preliminary experience.

    Science.gov (United States)

    Ceccarelli, Graziano; Codacci-Pisanelli, Massimo; Patriti, Alberto; Ceribelli, Cecilia; Biancafarina, Alessia; Casciola, Luciano

    2013-09-01

    Small renal masses (T1a) are commonly diagnosed incidentally and can be treated with nephron-sparing surgery, preserving renal function and obtaining the same oncological results as radical surgery. Bigger lesions (T1b) may be treated in particular situations with a conservative approach too. We present our surgical technique based on robotic assistance for nephron-sparing surgery. We retrospectively analysed our series of 32 consecutive patients (two with 2 tumours and one with 4 bilateral tumours), for a total of 37 robotic nephron-sparing surgery (RNSS) performed between June 2008 and July 2012 by a single surgeon (G.C.). The technique differs depending on tumour site and size. The mean tumour size was 3.6 cm; according to the R.E.N.A.L. Nephrometry Score 9 procedures were considered of low, 14 of moderate and 9 of hight complexity with no conversion in open surgery. Vascular clamping was performed in 22 cases with a mean warm ischemia time of 21.5 min and the mean total procedure time was 149.2 min. Mean estimated blood loss was 187.1 ml. Mean hospital stay was 4.4 days. Histopathological evaluation confirmed 19 cases of clear cell carcinoma (all the multiple tumours were of this nature), 3 chromophobe tumours, 1 collecting duct carcinoma, 5 oncocytomas, 1 leiomyoma, 1 cavernous haemangioma and 2 benign cysts. Associated surgical procedures were performed in 10 cases (4 cholecystectomies, 3 important lyses of peritoneal adhesions, 1 adnexectomy, 1 right hemicolectomy, 1 hepatic resection). The mean follow-up time was 28.1 months ± 12.3 (range 6-54). Intraoperative complications were 3 cases of important bleeding not requiring conversion to open or transfusions. Regarding post-operative complications, there were a bowel occlusion, 1 pleural effusion, 2 pararenal hematoma, 3 asymptomatic DVT (deep vein thrombosis) and 1 transient increase in creatinine level. There was no evidence of tumour recurrence in the follow-up. RNSS is a safe and feasible technique

  16. Optimization of fast dissolving etoricoxib tablets prepared by sublimation technique

    OpenAIRE

    Patel D; Patel M

    2008-01-01

    The purpose of this investigation was to develop fast dissolving tablets of etoricoxib. Granules containing etoricoxib, menthol, crospovidone, aspartame and mannitol were prepared by wet granulation technique. Menthol was sublimed from the granules by exposing the granules to vacuum. The porous granules were then compressed in to tablets. Alternatively, tablets were first prepared and later exposed to vacuum. The tablets were evaluated for percentage friability and disintegration time. A 3 2 ...

  17. Optimal deep neural networks for sparse recovery via Laplace techniques

    OpenAIRE

    Limmer, Steffen; Stanczak, Slawomir

    2017-01-01

    This paper introduces Laplace techniques for designing a neural network, with the goal of estimating simplex-constraint sparse vectors from compressed measurements. To this end, we recast the problem of MMSE estimation (w.r.t. a pre-defined uniform input distribution) as the problem of computing the centroid of some polytope that results from the intersection of the simplex and an affine subspace determined by the measurements. Owing to the specific structure, it is shown that the centroid ca...

  18. Transvaginal Cystocele Repair by Purse-String Technique Reinforced with Three Simple Sutures: Surgical Technique and Results

    Directory of Open Access Journals (Sweden)

    Ho-Sook Song

    2012-09-01

    Full Text Available Purpose Different techniques for cystocele repair including the conventional anterior colporrhaphy and mesh technique are known. Our goal was to evaluate the anatomical success and safety of our method of transvaginal anterior vaginal wall repair by the purse-string technique reinforced with three simple additional sutures in the repair of cystocele over a 4-year follow-up period. Methods This was a retrospective review of 69 consecutive patients (grades 2 to 4 who underwent the above operations between 2001 and 2011, including their success rates as assessed by use of the Baden-Walker halfway classification system. Results Of the patients, 62 patients (98% were completely cured of cystocele and 1 patient showed grade 2 cystocele recurrence that required no further treatment. Two patients with grade 4 cystocele were completely cured. There was no vaginal erosion related to the cystocele repair. Conclusions Transvaginal anterior colporrhaphy by a purse-string technique reinforced with simple additive sutures appears to be a simple, safe, and easily performed approach in cystocele repair. There is no need for other material for reinforcement, even in high-grade cystocele, which is an advantage of our technique.

  19. Three-Year Outcome of Fixed Partial Rehabilitations Supported by Implants Inserted with Flap or Flapless Surgical Techniques.

    Science.gov (United States)

    Maló, Paulo; de Araújo Nobre, Miguel; Lopes, Armando

    2016-07-01

    The aim of this prospective clinical study was to evaluate the 3-year outcome of fixed partial prostheses supported by implants with immediate provisionalization without occlusal contacts inserted in predominantly soft bone with flap and flapless protocols. Forty-one patients partially rehabilitated with 72 NobelSpeedy implants (51 maxillary; 21 mandibular) were consecutively included and treated with a flapless surgical protocol (n = 20 patients; 32 implants) and flapped surgical protocol (n = 21 patients; 40 implants). Primary outcome measure was implant survival; secondary outcome measures were marginal bone resorption (comparing the bone levels at 1 and 3 years with baseline) and the incidence of biological, mechanical, and esthetic complications. Survival was computed through life tables; descriptive statistics were applied to the remaining variables of interest. Eight patients with eight implants dropped out of the study. One implant failed in one patient (flapless group) giving an overall cumulative survival rate (CSR) of 98.6%. No failures were noted with the flapped protocol (CSR 100%), while for the implants placed with the flapless surgical technique, a 96.9% CSR was registered. The overall average marginal bone resorption at 3 years was 1.37 mm (SD = 0.94 mm), with 1.14 mm (SD = 0.49 mm) and 1.60 mm (SD = 1.22 mm) for the flap and flapless groups, respectively. Mechanical complications occurred in nine patients (n = 5 patients in the flapless group; n = 4 patients in the flap group). Implant infection was registered in three implants and three patients (flapless group), who exhibited inadequate oral hygiene levels. Partial edentulism rehabilitation through immediate provisionalization fixed prosthesis supported by dental implants inserted through flap or flapless surgical techniques in areas of predominantly soft bone was viable at 3 years of follow-up. The limitations and risks of the "free-hand" method in flapless surgery should be considered when

  20. Parallel processing based decomposition technique for efficient collaborative optimization

    International Nuclear Information System (INIS)

    Park, Hyung Wook; Kim, Sung Chan; Kim, Min Soo; Choi, Dong Hoon

    2001-01-01

    In practical design studies, most of designers solve multidisciplinary problems with large sized and complex design system. These multidisciplinary problems have hundreds of analysis and thousands of variables. The sequence of process to solve these problems affects the speed of total design cycle. Thus it is very important for designer to reorder the original design processes to minimize total computational cost. This is accomplished by decomposing large multidisciplinary problem into several MultiDisciplinary Analysis SubSystem (MDASS) and processing it in parallel. This paper proposes new strategy for parallel decomposition of multidisciplinary problem to raise design efficiency by using genetic algorithm and shows the relationship between decomposition and Multidisciplinary Design Optimization(MDO) methodology

  1. OPTIMAL DATA REPLACEMENT TECHNIQUE FOR COOPERATIVE CACHING IN MANET

    Directory of Open Access Journals (Sweden)

    P. Kuppusamy

    2014-09-01

    Full Text Available A cooperative caching approach improves data accessibility and reduces query latency in Mobile Ad hoc Network (MANET. Maintaining the cache is challenging issue in large MANET due to mobility, cache size and power. The previous research works on caching primarily have dealt with LRU, LFU and LRU-MIN cache replacement algorithms that offered low query latency and greater data accessibility in sparse MANET. This paper proposes Memetic Algorithm (MA to locate the better replaceable data based on neighbours interest and fitness value of cached data to store the newly arrived data. This work also elects ideal CH using Meta heuristic search Ant Colony Optimization algorithm. The simulation results shown that proposed algorithm reduces the latency, control overhead and increases the packet delivery rate than existing approach by increasing nodes and speed respectively.

  2. Nuclear fuel cycle optimization - methods and modelling techniques

    International Nuclear Information System (INIS)

    Silvennoinen, P.

    1982-01-01

    This book is aimed at presenting methods applicable in the analysis of fuel cycle logistics and optimization as well as in evaluating the economics of different reactor strategies. After a succinct introduction to the phases of a fuel cycle, uranium cost trends are assessed in a global perspective and subsequent chapters deal with the fuel cycle problems faced by a power utility. A fundamental material flow model is introduced first in the context of light water reactor fuel cycles. Besides the minimum cost criterion, the text also deals with other objectives providing for a treatment of cost uncertainties and of the risk of proliferation of nuclear weapons. Methods to assess mixed reactor strategies, comprising also other reactor types than the light water reactor, are confined to cost minimization. In the final Chapter, the integration of nuclear capacity within a generating system is examined. (author)

  3. Optimization of surgical treatment of cataract in patients with diabetes mellitus

    OpenAIRE

    Lipatov, D.; Chistyakov, T.; Kuzmin, A.

    2010-01-01

    Aim. To compare different methods for surgical treatment of cataract in patients with diabetes melli-tus (DM) and substantiate the choice of its optimalmodality. Materials and methods. Analysis included data on 209 patients (221 eyes) treated from January 2008 to December 2009 in the Department ofRetinopathy and Ophthalmosurgey, Endocrinological Research Centre. Diabetic cataract was managed using UNIVERSAL-II, LEGACY EVEREST,and INFINITI phacoemulsifiers. Parameters studied inc...

  4. Optimization of surgical correction of genital prolapse with subsequent tubal sterilization

    OpenAIRE

    NASIMOVA NIGINA RUSTAMOVNA

    2015-01-01

    Currently, pelvic organ prolapse is the most common pathology among women of reproductive age. For these patients it is relevant not only the correction of pelvic organ prolapse but also the search for the most effective contraceptive methods. Treatment of prolapse with simultaneous contraception for these patients is an actual problem of modern gynecology. This paper proposes a method of transvaginal voluntary surgical contraception, produced in conjunction with surgery descent and prolapse ...

  5. Patient-specific surgical planning and hemodynamic computational fluid dynamics optimization through free-form haptic anatomy editing tool (SURGEM).

    Science.gov (United States)

    Pekkan, Kerem; Whited, Brian; Kanter, Kirk; Sharma, Shiva; de Zelicourt, Diane; Sundareswaran, Kartik; Frakes, David; Rossignac, Jarek; Yoganathan, Ajit P

    2008-11-01

    The first version of an anatomy editing/surgical planning tool (SURGEM) targeting anatomical complexity and patient-specific computational fluid dynamics (CFD) analysis is presented. Novel three-dimensional (3D) shape editing concepts and human-shape interaction technologies have been integrated to facilitate interactive surgical morphology alterations, grid generation and CFD analysis. In order to implement "manual hemodynamic optimization" at the surgery planning phase for patients with congenital heart defects, these tools are applied to design and evaluate possible modifications of patient-specific anatomies. In this context, anatomies involve complex geometric topologies and tortuous 3D blood flow pathways with multiple inlets and outlets. These tools make it possible to freely deform the lumen surface and to bend and position baffles through real-time, direct manipulation of the 3D models with both hands, thus eliminating the tedious and time-consuming phase of entering the desired geometry using traditional computer-aided design (CAD) systems. The 3D models of the modified anatomies are seamlessly exported and meshed for patient-specific CFD analysis. Free-formed anatomical modifications are quantified using an in-house skeletization based cross-sectional geometry analysis tool. Hemodynamic performance of the systematically modified anatomies is compared with the original anatomy using CFD. CFD results showed the relative importance of the various surgically created features such as pouch size, vena cave to pulmonary artery (PA) flare and PA stenosis. An interactive surgical-patch size estimator is also introduced. The combined design/analysis cycle time is used for comparing and optimizing surgical plans and improvements are tabulated. The reduced cost of patient-specific shape design and analysis process, made it possible to envision large clinical studies to assess the validity of predictive patient-specific CFD simulations. In this paper, model

  6. Combined Surgical Treatment of Gynecomastia

    Directory of Open Access Journals (Sweden)

    Yordanov Y.

    2015-05-01

    Full Text Available Surgical treatment of gynecomastia could present unique challenges for the plastic surgeon. Achieving a good balance between effectiveness of the selected approach and the satisfactory aesthetic outcome often is a difficult endeavor. Optimal surgical treatment involves a combination of liposuction and direct excision. In the present study the charts of 11 patients treated with suction-assisted liposuction and direct surgical excision were retrospectively reviewed; a special emphasis is placed on the surgical technique. The mean follow-up period of the patients was 11.6 months. No infection, hematoma, nipple-areola complex necrosis and nipple retraction was encountered in this series. The combined surgical treatment of gynecomastia has shown to be a reliable technique in both small and moderate breast enlargement including those with skin excess.

  7. 3D Computer graphics simulation to obtain optimal surgical exposure during microvascular decompression of the glossopharyngeal nerve.

    Science.gov (United States)

    Hiraishi, Tetsuya; Matsushima, Toshio; Kawashima, Masatou; Nakahara, Yukiko; Takahashi, Yuichi; Ito, Hiroshi; Oishi, Makoto; Fujii, Yukihiko

    2013-10-01

    The affected artery in glossopharyngeal neuralgia (GPN) is most often the posterior inferior cerebellar artery (PICA) from the caudal side or the anterior inferior cerebellar artery (AICA) from the rostral side. This technical report describes two representative cases of GPN, one with PICA as the affected artery and the other with AICA, and demonstrates the optimal approach for each affected artery. We used 3D computer graphics (3D CG) simulation to consider the ideal transposition of the affected artery in any position and approach. Subsequently, we performed microvascular decompression (MVD) surgery based on this simulation. For PICA, we used the transcondylar fossa approach in the lateral recumbent position, very close to the prone position, with the patient's head tilted anteriorly for caudal transposition of PICA. In contrast, for AICA, we adopted a lateral suboccipital approach with opening of the lateral cerebellomedullary fissure, to visualize better the root entry zone of the glossopharyngeal nerve and to obtain a wide working space in the cerebellomedullary cistern, for rostral transposition of AICA. Both procedures were performed successfully. The best surgical approach for MVD in patients with GPN is contingent on the affected artery--PICA or AICA. 3D CG simulation provides tailored approach for MVD of the glossopharyngeal nerve, thereby ensuring optimal surgical exposure.

  8. Assessment of resectability of pancreatic cancer with dynamic contrast-enhanced MR imaging: technique, surgical correlation and patient outcome

    International Nuclear Information System (INIS)

    Spencer, J.A.; Ward, J.; Guthrie, J.A.; Robinson, P.J.A.; Guillou, P.J.

    1998-01-01

    The aim of our work was to investigate the use of a dynamic contrast-enhanced MR (DCEMR) technique for staging apparently localised pancreatic cancer, and to determine the patterns of tumour and vascular enhancement with this technique. Thirty-five consecutive patients were examined. The MR findings were correlated with surgical findings in 13 patients and with clinical outcome in 22 patients. Breath-hold gradient-echo fast low angle shot (TR = 100, TE = 4, flip angle 80 ) acquisitions were obtained at 10 and 40 s (right anterior coronal oblique plane) and at 90 s (axial plane) following intravenous gadolinium. Mean contrast-to-noise ratio was higher on the first than the second acquisition (p < 0.001) and higher on the second acquisition than the third (p < 0.005). Tumour conspicuity was greatest and arterial anatomy was best demonstrated on the first acquisition and the portal venous anatomy on the second. Small tumours were isointense by the third acquisition. Maximal intensity projections were helpful. The MR findings correctly predicted the surgical findings in 11 of 13 cases (85 %) and the clinical course in the other 22 patients. The DCEMR imaging technique is valuable in the staging of patients with pancreatic cancer. Capillary and portal venous phase images are both required for complete local staging. (orig.)

  9. Bilateral sacroiliac luxation fixation using a single transiliosacral pin: surgical technique and clinical outcomes in eight cats.

    Science.gov (United States)

    Parslow, A; Simpson, D J

    2017-06-01

    A very limited safe anatomical window for transiliosacral implant placement exists in cats (sacroiliac fixation in cats using a single implant to minimise inadvertent iatrogenic damage to local structures and restore pelvic canal diameter. Eight cats underwent surgical fixation for traumatic bilateral sacroiliac luxation using a single smooth intramedullary pin. The pin spanned both ilial wings and sacrum. Implants were applied using a Universal C-guide. Pre- and postsurgery pelvic canal diameter ratios were calculated. Short-term follow-up was performed at 10 to 14 days postoperatively. Long-term follow-up was performed using the Feline Musculoskeletal Pain Index Questionnaire. Long-term radiographic assessment was available in two cases. The technique achieved safe and accurate implant position with precise sacroiliac joint reduction. Pelvic canal diameter ratios were restored to normal in all cases. Rapid return to normal hind leg function and excellent long-term clinical outcomes were achieved. This technique offers a simple, safe, repeatable and affordable technique for treating bilateral sacroiliac luxations in the cat without the aid of fluoroscopy. The procedure can be performed using surgical tools and inventory readily available in general small animal practices. © 2017 British Small Animal Veterinary Association.

  10. Transanal endoscopic microsurgery as technique surgical for the treatment of the rectal adenocarcinoma: history, evolution and current tendency

    International Nuclear Information System (INIS)

    Vega Padilla, Luis Carlos

    2013-01-01

    The modalities of local and minimally invasive treatment were described for early rectal adenocarcinomas. The most adequate diagnostic studies and interdisciplinary interactions involved were considered in the process and the therapeutic results, in comparison with the current radical treatments. The historical evolution of the different surgical techniques developed over time, and the anatomical and physiological concepts were reviewed. The epidemiological behavior of the disease was documented according to gender, age and most prevalent sites to direct the possible risk groups to suffer the disease. Risk factors that affect patients with colorectal cancer were identified and related to the environment, social habits and hereditary. The different genetic syndromes involved in colorectal cancer, its physiopathology and clinical manifestations and implications were examined with respect to colorectal cancer. Colorectal cancer was defined according to the updated classifications of the American Joint Cancer Committee, according to the depth, affectation of lymph nodes and metastasis to distant organs, in relation to its clinical stage. Current surgical techniques were named to treat early adenocarcinomas of inferior rectus. The different risk factors were analyzed to allow local resections of the early rectal tumors, from the histopalogical, radiological and clinical point of view. The traditional techniques of transanal and radical resection were compared against the transanal endoscopic microsurgery between different aspects such as technical difficulty, recurrence rate, morbidity and mortality, and economic cost [es

  11. Fixation of Hydroxyapatite-Coated Revision Implants Is Improved by the Surgical Technique of Cracking the Sclerotic Bone Rim

    Science.gov (United States)

    Elmengaard, Brian; Bechtold, Joan E.; Chen, Xinqian; Søballe, Kjeld

    2013-01-01

    Revision joint replacement has poorer outcomes that have been associated with poorer mechanical fixation. We investigate a new bone-sparing surgical technique that locally cracks the sclerotic bone rim formed during aseptic loosening. We inserted 16 hydroxyapatite-coated implants bilaterally in the distal femur of eight dogs, using a controlled weight-bearing experimental model that replicates important features of a typical revision setting. At 8 weeks, a control revision procedure and a crack revision procedure were performed on contralateral implants. The crack procedure used a splined tool to perform a systematic local perforation of the sclerotic bone rim of the revision cavity. After 4 weeks, the hydroxyapatite-coated implants were evaluated for mechanical fixation by a push-out test and for tissue distribution by histomorphometry. The cracking revision procedure resulted in significantly improved mechanical fixation, significantly more bone ongrowth and bone volume in the gap, and reduced fibrous tissue compared to the control revision procedure. The study demonstrates that the sclerotic bone rim prevents bone ingrowth and promotes fixation by fibrous tissue. The effect of the cracking technique may be due to improved access to the vascular compartment of the bone. The cracking technique is a simple surgical method that potentially can improve the fixation of revision implants in sclerotic regions important for obtaining the fixation critical for overall implant stability. PMID:19148940

  12. Pulmonary CT angiography: optimization of contrast enhancement technique

    International Nuclear Information System (INIS)

    Ma Lianju; Tang Guangjian; Fu Jiazhen

    2012-01-01

    Objective: To derive and evaluate the formula of exactly calculating the contrast dosage used during pulmonary CT angiography (CTPA). Methods: Time density curves in 27 patients who underwent CTPA were collected and analyzed,the formula for calculating contrast dosage during CTPA was derived. 68 patients suspected of pulmonary embolism (PE) clinically but no PE on CTPA were divided randomly into group A, with bolus tracing technique (n=26), and group B, with small dose injection contrast test (SDCT) (n=42). The CT values of the right main pulmonary artery (RMPA), right upper pulmonary vein (RUPV), right posterior basal PA, right lower PV (RLPV) and the aorta were calculated. The total contrast dosage and the hard beam artifact in the SVC were compared between the two groups.Student's t test, Chi-square test and Mann-Whitney U test were used. Results: The ratio of the time from starting injection to enhancement peak of caudal end of SVC and the time to enhancement peak of the main pulmonary trunk was 0.65 ±0.09 (about 2/3), the formula for contrast dosage calculation was derived as (DTs/3 + STs/2) FR ml/s. The CT values of RMPA and RLPA between the two groups [(301 ±117), (329 ± 122) and (283 ±95), (277 ±98) HU respectively] were not significantly different (t=1.060, P=0.292; t=2.056, P=0.044), but the differences of CT values in the paired PA and PV between the two groups (median were 22.5, 58.0 and 170.5, 166.5 HU respectively) were significant (U=292, P=0.001 and U=325, P=0.005), contrast artifact of the SVC (grade 1-3) in group B (n=34, 7, 1 respectively) was significantly less than in group A (n=11, 10, 5 respectively, χ 2 =10.714, P=0.002), the contrast dosage injected in group A was ( 87.6 ± 7.3) ml, and in group B was (40.0 ±5.4) ml (P<0.01). Conclusion: CTPA with SDCT technique is superior to that with conventional bolus tracing technique regarding contrast dosage and contrast artifact in the SVC. (authors)

  13. Efficacy of surgical techniques and factors affecting residual stone rate in the treatment of kidney stones.

    Science.gov (United States)

    Aydemir, Hüseyin; Budak, Salih; Kumsar, Şükrü; Köse, Osman; Sağlam, Hasan Salih; Adsan, Öztuğ

    2014-09-01

    In this study, we aimed to evaluate, the efficacy of surgical methods and the factors affecting the residual stone rate by scrutinizing retrospectively the patients who had undergone renal stone surgery. Records of 109 cases of kidney stones who had been surgically treated between January 2010, and July 2013 were reviewed. Patients were divided into three groups in terms of surgical treatment; open stone surgery, percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgery (RIRS). Patients' history, physical examination, biochemical and radiological images and operative and postoperative data were recorded. The patients had undergone PNL (n=74; 67.9%), RIRS (n=22;20.2%), and open renal surgery (n=13; 11.9%). The mean and median ages of the patients were 46±9, 41 (21-75) and, 42 (23-67) years, respectively. The mean stone burden was 2.6±0.7 cm(2) in the PNL, 1.4±0.1 cm(2) in the RIRS, and 3.1±0.9 cm(2) in the open surgery groups. The mean operative times were 126±24 min in the PNL group, 72±12 min in the RIRS group and 82±22 min in the open surgery group. The duration of hospitalisation was 3.1±0.2 days, 1.2±0.3 days and 3.4±1.1 days respectively. While the RIRS group did not need blood transfusion, in the PNL group blood transfusions were given in the PNL (n=18), and open surgery (n=2) groups. Residual stones were detected in the PNL (n=22), open surgery (n=2), and RIRS (n=5) groups. PNL and RIRS have been seen as safe and effective methods in our self application too. However, it should not be forgotten that as a basical method, open surgery may be needed in cases of necessity.

  14. Surgical closure of persistent arterial duct with minimal invasive anterior thoracotomy: an alternative technique.

    Science.gov (United States)

    Fouilloux, Virginie; Gran, Célia; Kreitmann, Bernard

    2014-10-01

    Surgical approach for persistent ductus arteriosus ligation is typically a left lateral thoracotomy opening the pleural-space with left lung retraction. We describe an alternative approach, with a minimally invasive anterior parasternal incision. This is particularly adapted to preterm infants weighing less than 1.5 kg. This approach ensures a good exposure of vessels. We believe that it is safe, reliable and reproducible. The learning curve should not be an issue for surgeons used to manage low weight patients. Georg Thieme Verlag KG Stuttgart · New York.

  15. Optimal time-domain technique for pulse width modulation in power electronics

    Directory of Open Access Journals (Sweden)

    I. Mayergoyz

    2018-05-01

    Full Text Available Optimal time-domain technique for pulse width modulation is presented. It is based on exact and explicit analytical solutions for inverter circuits, obtained for any sequence of input voltage rectangular pulses. Two optimal criteria are discussed and illustrated by numerical examples.

  16. Application of Advanced Particle Swarm Optimization Techniques to Wind-thermal Coordination

    DEFF Research Database (Denmark)

    Singh, Sri Niwas; Østergaard, Jacob; Yadagiri, J.

    2009-01-01

    wind-thermal coordination algorithm is necessary to determine the optimal proportion of wind and thermal generator capacity that can be integrated into the system. In this paper, four versions of Particle Swarm Optimization (PSO) techniques are proposed for solving wind-thermal coordination problem...

  17. Static antibiotic spacers augmented by calcium sulphate impregnated beads in revision TKA: Surgical technique and review of literature.

    Science.gov (United States)

    Risitano, Salvatore; Sabatini, Luigi; Atzori, Francesco; Massè, Alessandro; Indelli, Pier Francesco

    2018-06-01

    Periprosthetic joint infection (PJI) is a serious complication in total knee arthroplasty (TKA) and represents one of the most common causes of revision. The challenge for surgeons treating an infected TKA is to quickly obtain an infection-free joint in order to re-implant, when possible, a new TKA. Recent literature confirms the role of local antibiotic-loaded beads as a strong bactericidal, allowing higher antibiotic elution when compared with antibiotic loaded spacers only. Unfortunately, classical Polymethylmethacrylate (PMMA) beads might allow bacteria adhesion, secondary development of antibiotic resistance and eventually surgical removal once antibiotics have eluted. This article describes a novel surgical technique using static, custom-made antibiotic loaded spacers augmented by calcium sulphate antibiotic-impregnated beads to improve the success rate of revision TKA in a setting of PJI. The use of calcium sulphate beads has several potential benefits, including a longer sustained local antibiotic release when compared with classical PMMA beads and, being resorbable, not requiring accessory surgical interventions.

  18. “A Tree Must Be Bent While It Is Young”: Teaching Urological Surgical Techniques to Schoolchildren

    Science.gov (United States)

    Buntrock, Stefan

    2012-01-01

    Background Playing video games in childhood may help achieve advanced laparoscopic skills later in life. The virtual operating room will soon become a reality, as “doctor games 2.0” will doubtlessly begin to incorporate virtual laparoscopic techniques. Objectives To teach surgical skills to schoolchildren in order to attract them to urology as a professional choice later in life. Materials and Methods As part of EAU Urology Week 2010, 108 school children aged 15–19 attended a seminar with lectures and simulators (laparoscopy, TUR, cystoscopy, and suture sets) at the 62nd Congress of the German Society of Urology in Düsseldorf. A Pub-Med and Google Scholar search was also performed in order to review the beneficial effects of early virtual surgical training. MeSh terms used were “video games,” “children,” and “surgical skills.” Searches were performed without restriction for a certain period of time. Results In terms of publicity for urology, EAU Urology Week, and the German Society of Urology, the event was immensely successful. Regarding the literature search, four relevant publications were found involving children. An additional three articles evaluated the usefulness of video gaming in medical students and residents. Conclusions Making use of virtual reality to attract and educate a new generation of urologists is an important step in designing the future of urology. PMID:23573467

  19. When Is the Optimal Timing of the Surgical Treatment for Secondary Spontaneous Pneumothorax?

    Science.gov (United States)

    Jeon, Hyun Woo; Kim, Young-Du; Choi, Si Young; Park, Jae Kil

    2017-01-01

    Objectives  The definition of spontaneous pneumothorax is accumulation of air in the pleural space, resulting in dyspnea or chest pain. Unlike primary spontaneous pneumothorax, secondary pneumothorax can be a life-threatening condition and spontaneous healing rate is uncommon. Although surgery is the most effective treatment modality for pneumothorax, surgical management and timing is difficult where there is underlying lung disease and/or medical comorbidities. Prolonged air leakage increases the morbidity and mortality in thoracic surgery. We hypothesized that duration of air leakage before operation may lead to increase in complications. Methods  This study is a retrospective review of 155 consecutive patients with air leakage who underwent bullectomy for secondary spontaneous pneumothorax from January 2005 to July 2013. The patients were divided according to the duration of preoperative air leakage. The patients were followed-up until the time of last visit or death. Postoperative morbidity and mortality were assessed and the risk factors for complications were analyzed. Results  The median age was 65 years (range, 52-88) with male predominance (96.13%). The median duration of preoperative air leakage was 6 days (range, 1-30). The median surgery time was 90 minutes (range, 25-300) and median hospital stay after operation was 7 days (range, 3-75). Postoperative complications occurred in 38 patients (24.52%) and postoperative recurrence was shown to have occurred in 8 patients (5.16%). With multivariate analysis, risk factors for postoperative complications were: underlying interstitial lung disease and air leakage > 5 days before operation. Conclusion  Persistent air leakage was a major surgical indication for pneumothorax. Early surgical treatment reduced postoperative complications for secondary spontaneous pneumothorax. Georg Thieme Verlag KG Stuttgart · New York.

  20. Optimization of the extent of surgical treatment in patients with stage I in cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshova, A. L.; Lyapunov, A. Yu., E-mail: Lyapunov1720.90@mail.ru [Tomsk Cancer Research Institute, Kooperativny Street 5, Tomsk, 634050 (Russian Federation); Kolomiets, L. A. [Tomsk Cancer Research Institute, Kooperativny Street 5, Tomsk, 634050 (Russian Federation); Siberian State Medical University, Moskovsky Trakt 2, Tomsk, 634050 (Russian Federation); Sinilkin, I. G.; Chernov, V. I. [Tomsk Cancer Research Institute, Kooperativny Street 5, Tomsk, 634050 (Russian Federation); Tomsk Polytechnic University, Lenin Avenue 30, Tomsk, 634050 (Russian Federation)

    2016-08-02

    The study included 26 patients with FIGO stage Ia1–Ib1 cervical cancer who underwent fertility-sparing surgery (transabdominaltrachelectomy). To visualize sentinel lymph nodes, lymphoscintigraphy with injection of 99mTc-labelled nanocolloid was performed the day before surgery. Intraoperative identification of sentinel lymph nodes using hand-held gamma probe was carried out to determine the radioactive counts over the draining lymph node basin. The sentinel lymph node detection in cervical cancer patients contributes to the accurate clinical assessment of the pelvic lymph node status, precise staging of the disease and tailoring of surgical treatment to individual patient.

  1. Surgical management of peptic ulcer disease today--indication, technique and outcome.

    Science.gov (United States)

    Zittel, T T; Jehle, E C; Becker, H D

    2000-03-01

    The current surgical management of peptic ulcer disease and its outcome have been reviewed. Today, surgery for peptic ulcer disease is largely restricted to the treatment of complications. In peptic ulcer perforation, a conservative treatment trial can be given in selected cases. If laparotomy is necessary, simple closure is sufficient in the large majority of cases, and definitive ulcer surgery to reduce gastric acid secretion is no longer justified in these patients. Laparoscopic surgery for perforated peptic ulcer has failed to prove to be a significant advantage over open surgery. In bleeding peptic ulcers, definitive hemostasis can be achieved by endoscopic treatment in more than 90% of cases. In 1-2% of cases, immediate emergency surgery is necessary. Some ulcers have a high risk of re-bleeding, and early elective surgery might be advisable. Surgical bleeding control can be achieved by direct suture and extraluminal ligation of the gastroduodenal artery or by gastric resection. Benign gastric outlet obstruction can be controlled by endoscopic balloon dilatation in 70% of cases, but gastrojejunostomy or gastric resection are necessary in about 30% of cases. Elective surgery for peptic ulcer disease has been largely abandoned, and bleeding or obstructing ulcers can be managed safely by endoscopic treatment in most cases. However, surgeons will continue to encounter patients with peptic ulcer disease for emergency surgery. Currently, laparoscopic surgery has no proven advantage in peptic ulcer surgery.

  2. Lateral Interbody Fusion for Treatment of Discogenic Low Back Pain: Minimally Invasive Surgical Techniques

    Directory of Open Access Journals (Sweden)

    Luis Marchi

    2012-01-01

    Full Text Available Low back pain is one of the most common ailments in the general population, which tends to increase in severity along with aging. While few patients have severe enough symptoms or underlying pathology to warrant surgical intervention, in those select cases treatment choices remain controversial and reimbursement is a substancial barrier to surgery. The object of this study was to examine outcomes of discogenic back pain without radiculopathy following minimally-invasive lateral interbody fusion. Twenty-two patients were treated at either one or two levels (28 total between L2 and 5. Discectomy and interbody fusion were performed using a minimallyinvasive retroperitoneal lateral transpsoas approach. Clinical and radiographic parameters were analyzed at standard pre- and postoperative intervals up to 24 months. Mean surgical duration was 72.1 minutes. Three patients underwent supplemental percutaneous pedicle screw instrumentation. Four (14.3% stand-alone levels experienced cage subsidence. Pain (VAS and disability (ODI improved markedly postoperatively and were maintained through 24 months. Segmental lordosis increased significantly and fusion was achieved in 93% of levels. In this series, isolated axial low back pain arising from degenerative disc disease was treated with minimally-invasive lateral interbody fusion in significant radiographic and clinical improvements, which were maintained through 24 months.

  3. Repair of Total Tractional Retinal Detachment in Norrie Disease: Report of Technique and Successful Surgical Outcome.

    Science.gov (United States)

    Todorich, Bozho; Thanos, Aristomenis; Yonekawa, Yoshihiro; Capone, Antonio

    2017-03-01

    Norrie disease is a rare, but devastating cause of pediatric retinal detachment, universally portending a poor visual prognosis. This paper describes successful surgical management of an infant with total retinal detachment associated with Norrie disease mutation. The infant was a full-term white male who presented with bilateral total funnel retinal detachments (RDs). He underwent genetic testing, which demonstrated single-point mutation 133 G>A transition in exon 2 of the NDP gene. The retinal detachment was managed with translimbal iridectomy, lensectomy, capsulectomy, and vitrectomy. Careful dissection of the retrolental membranes resulted in opening of the funnel. Single-stage surgery in this child's eye achieved re-attachment of the posterior pole with progressive reabsorption of subretinal fluid and cholesterol without the need for external drainage. Fluorescein angiography, performed at 2 months postoperatively, demonstrated perfusion of major vascular arcades, but with significant abnormalities and aneurysmal changes of higher-order vessels, suggestive of retinal and vascular dysplasia. The child has maintained brisk light perception vision. Early surgical intervention with careful dissection of tractional tissues can potentially result in good anatomic outcomes in some patients with Norrie disease-associated retinal detachment. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:260-262.]. Copyright 2017, SLACK Incorporated.

  4. Optimization in multi-implant placement for immediate loading in edentulous arches using a modified surgical template and prototyping: a case report.

    Science.gov (United States)

    Jayme, Sérgio J; Muglia, Valdir A; de Oliveira, Rafael R; Novaes, Arthur B Júnior

    2008-01-01

    Immediate loading of dental implants shortens the treatment time and makes it possible to give the patient an esthetic appearance throughout the treatment period. Placement of dental implants requires precise planning that accounts for anatomic limitations and restorative goals. Diagnosis can be made with the assistance of computerized tomographic scanning, but transfer of planning to the surgical field is limited. Recently, novel CAD/CAM techniques such as stereolithographic rapid prototyping have been developed to build surgical guides in an attempt to improve precision of implant placement. The aim of this case report was to show a modified surgical template used throughout implant placement as an alternative to a conventional surgical guide.

  5. Optimized digital filtering techniques for radiation detection with HPGe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Salathe, Marco, E-mail: marco.salathe@mpi-hd.mpg.de; Kihm, Thomas, E-mail: mizzi@mpi-hd.mpg.de

    2016-02-01

    This paper describes state-of-the-art digital filtering techniques that are part of GEANA, an automatic data analysis software used for the GERDA experiment. The discussed filters include a novel, nonlinear correction method for ballistic deficits, which is combined with one of three shaping filters: a pseudo-Gaussian, a modified trapezoidal, or a modified cusp filter. The performance of the filters is demonstrated with a 762 g Broad Energy Germanium (BEGe) detector, produced by Canberra, that measures γ-ray lines from radioactive sources in an energy range between 59.5 and 2614.5 keV. At 1332.5 keV, together with the ballistic deficit correction method, all filters produce a comparable energy resolution of ~1.61 keV FWHM. This value is superior to those measured by the manufacturer and those found in publications with detectors of a similar design and mass. At 59.5 keV, the modified cusp filter without a ballistic deficit correction produced the best result, with an energy resolution of 0.46 keV. It is observed that the loss in resolution by using a constant shaping time over the entire energy range is small when using the ballistic deficit correction method.

  6. Optimization of digital radiography techniques for specific application

    International Nuclear Information System (INIS)

    Harara, W.

    2010-12-01

    A low cost digital radiography system (DRS) for testing weld joints and castings in laboratory was assembled. The DRS is composed from X-ray source, scintillator, first surface mirror with Aluminum coating, charged coupled device (CCD) camera and lens. The DRS was used to test flawed carbon steel welded plates with thicknesses up to 12 mm. The comparison between the digital radiographs of the plates weldments and the radiographs of the same plates weldments using medium speed film type had shown that, the detection capability of the weld flaws are nearly identical for the two radiography techniques, while the sensitivity achieved in digital radiography of the plates weldments was one IQI wire less than the sensitivity achieved by conventional radiography of the same plates weldments according to EN 462-1. Further, the DRS was also successfully used to test (100 x 100 x 100) mm Aluminum casting with artificial flaws of varied dimensions and orientations. The resulted digital radiographs of the casting show that, all the flaws had been detected and their dimensions can be measured accurately, this confirm that, The proposed DRS can be used to detect and measure the flaws in the Aluminum and others light metals castings accurately. (author)

  7. Orange Peel Excision of Gland: A Novel Surgical Technique for Treatment of Gynecomastia.

    Science.gov (United States)

    S S, Shirol

    2016-12-01

    Gynecomastia is a common aesthetic problem faced by men with reported incidence as high as 65% with serious psychosocial impact. Although various techniques of liposculpture combined with glandular excision is the standard of treatment, many of the glandular excision techniques have inherent limitations and complications such as leaving a long scar, long operative time, contour abnormalities, and increased risk of hematoma. Here, we describe an innovative "the orange peel excision of gland (OPEG) technique" which overcomes these limitations with excellent cosmetic results. A total of 38 breasts were operated in 20 patients (18 bilateral and 2 unilateral). All the patients underwent suction-assisted liposuction and glandular excision under general anesthesia by our OPEG technique. The average operative time per breast was 60 minutes. One patient had a small hematoma which did not require evacuation. The patient satisfaction rate was 95%. The technique has reduced operative time and avoids residual gland and hematoma with excellent aesthetic outcome.

  8. 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.

  9. Contralateral breast doses measured by film dosimetry: tangential techniques and an optimized IMRT technique

    International Nuclear Information System (INIS)

    Saur, S; Frengen, J; Fjellsboe, L M B; Lindmo, T

    2009-01-01

    The contralateral breast (CLB) doses for three tangential techniques were characterized by using a female thorax phantom and GafChromic EBT film. Dose calculations by the pencil beam and collapsed cone algorithms were included for comparison. The film dosimetry reveals a highly inhomogeneous dose distribution within the CLB, and skin doses due to the medial fields that are several times higher than the interior dose. These phenomena are not correctly reproduced by the calculation algorithms. All tangential techniques were found to give a mean CLB dose of approximately 0.5 Gy. All wedged fields resulted in higher CLB doses than the corresponding open fields, and the lateral open fields resulted in higher CLB doses than the medial open fields. More than a twofold increase in the mean CLB dose from the medial open field was observed for a 90 deg. change of the collimator orientation. Replacing the physical wedge with a virtual wedge reduced the mean dose to the CLB by 35% and 16% for the medial and lateral fields, respectively. Lead shielding reduced the skin dose for a tangential technique by approximately 50%, but the mean CLB dose was only reduced by approximately 11%. Finally, a technique based on open medial fields in combination with several IMRT fields is proposed as a technique for minimizing the CLB dose. With and without lead shielding, the mean CLB dose using this technique was found to be 0.20 and 0.27 Gy, respectively.

  10. Treatment of complex internal carotid artery aneurysms using radial artery grafts. Surgical technique, perioperative complications, and results in 17 patients

    International Nuclear Information System (INIS)

    Murai, Yasuo; Teramoto, Akira; Mizunari, Takayuki; Kobayashi, Shiro; Kamiyama, Hiroyasu

    2007-01-01

    Complex giant or large internal carotid artery aneurysms present a surgical challenge because limitations and difficulty are encountered with either clipping or endovascular treatment. Our review of previous reports suggests that no current vascular assessment can accurately predict the occurrence of ischemic complications after internal carotid artery ligation. The present study concerns surgical technique, complications, and clinical outcome of radial artery grafting followed by parent artery trapping or proximal occlusion for management of these difficult lesions. Between September 1997 and October 2005, we performed radial artery grafting followed immediately by parent artery occlusion in 17 patients with giant or large complex intracranial carotid aneurysms (3 men, 14 women; mean follow-up duration, 62 months). All patients underwent postoperative digital subtraction angiography to assess graft patency and aneurysm obliteration. All 17 aneurysms were excluded from the cerebral circulation, with all radial artery grafts patent. Among 4 patients with cranial nerve disturbances, dysfunction was temporary in 5; in the others, oculomotor nerve paresis persisted. No perioperative cerebral infarction occurred. Sensory aphasia reflecting cerebral contusions caused by temporal lobe retraction resolved within 2 months, as did hemiparesis from a postoperative epidural hematoma. With appropriate attention to surgical technique, radial artery grafting followed by acute parent artery occlusion is a safe treatment for complex internal carotid artery aneurysms. Graft patency and aneurysm thrombosis were achieved in all patients. Cranial nerve dysfunction (III, VI) caused by altered blood flow from the internal carotid artery after occlusion was the most common complication and typically was temporary. In our experience with these difficult aneurysms, not only clipping but also reconstruction of the internal carotid artery was required, especially for wide-necked symptomatic

  11. A critical analysis of penile enhancement procedures for patients with normal penile size: surgical techniques, success, and complications.

    Science.gov (United States)

    Vardi, Yoram; Har-Shai, Yaron; Harshai, Yaron; Gil, Tamir; Gruenwald, Ilan

    2008-11-01

    Most men who request surgical penile enhancement have a normal-sized and fully functional penis but visualize their penises as small (psychological dysmorphism). The aim of this review is to describe the various reported techniques and to provide the available scientific data on the success and complication rates of penile enhancement procedures. We performed an extensive systematic review based on a search of the MEDLINE database for articles published between 1965 and 2008. The following key words were used: penis, enhancement, enlargement, phalloplasty, reconstruction, girth, lengthening, and augmentation. Only English-language articles that were related to penile surgery and dysmorphobia were sought. We excluded articles in which fewer than five cases were described and articles in which the type of surgical treatment and the outcome were not clear. Of the 176 papers found, 34 were selected and critically analyzed. We found only a small number of well-designed and comprehensive studies, and most of the published articles reported data that were obtained from small cohorts of patients. The more recently published studies presented better methodologies and descriptions of the surgical techniques than did the older publications. In general, penile enhancement surgery can cause a 1-2-cm increase in penile length and a 2.5-cm augmentation of penile girth. Unwanted outcomes and complications, namely penile deformity, paradoxical penile shortening, disagreeable scarring, granuloma formation, migration of injected material, and sexual dysfunction were reported frequently in these studies. Disappointing short- and long-term patient satisfaction rates following these procedures were also reported in most studies. To date, the use of cosmetic surgery to enlarge the penis remains highly controversial. There is a lack of any standardization of all described procedures. Indications and outcome measures are poorly defined, and the reported complications are unacceptably high

  12. Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio-Inspired Optimization Techniques

    Science.gov (United States)

    2017-11-01

    on Bio -Inspired Optimization Techniques by Canh Ly, Nghia Tran, and Ozlem Kilic Approved for public release; distribution is...Research Laboratory Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio -Inspired Optimization Techniques by...SUBTITLE Methodology for Designing and Developing a New Ultra-Wideband Antenna Based on Bio -Inspired Optimization Techniques 5a. CONTRACT NUMBER

  13. Recurrent Tricuspid Insufficiency: Is the Surgical Repair Technique a Risk Factor?

    OpenAIRE

    Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

    2013-01-01

    This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair.

  14. A surgical technique for lengthening tight hamstring muscles in patients with low back pain.

    Science.gov (United States)

    Anglès, F G; Manubens, X B; Anglès, F C

    1997-01-01

    An original technique for lengthening primary tight semitendinosus and semimembranosus muscles in their proximal portion is presented. The authors consider that primary shortening of these muscles rebounds on hip biomechanics and on the spine kinematics chain.

  15. The optimal injection technique for the osteoarthritic ankle: A randomized, cross-over trial

    NARCIS (Netherlands)

    Witteveen, Angelique G. H.; Kok, Aimee; Sierevelt, Inger N.; Kerkhoffs, Gino M. M. J.; van Dijk, C. Niek

    2013-01-01

    Background: To optimize the injection technique for the osteoarthritic ankle in order to enhance the effect of intra-articular injections and minimize adverse events. Methods: Randomized cross-over trial. Comparing two injection techniques in patients with symptomatic ankle osteoarthritis. Patients

  16. Virtual Power Plant and Microgrids controller for Energy Management based on optimization techniques

    Directory of Open Access Journals (Sweden)

    Maher G. M. Abdolrasol

    2017-06-01

    Full Text Available This paper discuss virtual power plant (VPP and Microgrid controller for energy management system (EMS based on optimization techniques by using two optimization techniques namely Backtracking search algorithm (BSA and particle swarm optimization algorithm (PSO. The research proposes use of multi Microgrid in the distribution networks to aggregate the power form distribution generation and form it into single Microgrid and let these Microgrid deal directly with the central organizer called virtual power plant. VPP duties are price forecast, demand forecast, weather forecast, production forecast, shedding loads, make intelligent decision and for aggregate & optimizes the data. This huge system has been tested and simulated by using Matlab simulink. These paper shows optimizations of two methods were really significant in the results. But BSA is better than PSO to search for better parameters which could make more power saving as in the results and the discussion.

  17. Professional burnout syndrome in doctors of surgical specialties in Ukraine: causes, consequences, labor optimization ways.

    Science.gov (United States)

    Skurupii, Dmytro A; Kholod, Dmytro A; Sonnik, Evgen G

    The professional burnout syndrome (PBS) affects quality of medical care provision for people, which is acquires the special actuality in terms of reforming the health care system. To study ways to improve the efficiency of doctors of surgical specialties based on analyzes of PBS and its consequences. A survey of psychological tests and 62 surgical doctors was carried out. It was found out that the PBS reaches a peak after 11 to 15 years of working experience. Anesthesiologists have high levels of PBS, emotional exhaustion, cynicism, low desire for career growth, frequent misunderstanding with the administration, they prefer 8-hour working day, and relieve stress by sleeping and consuming alcohol. Obstetrician-gynecologists show moderate level of PBS and emotional exhaustion, high degree of cynicism, strong desire for career growth, frequent misunderstandings with patients and their relatives, prefer 8-hour working day, relieve stress by smoking and socializing with family and friends. Traumatic surgeons have moderate level of PBS, emotional exhaustion, high degree of cynicism, strong desire for career growth, frequent misunderstandings with their colleagues of related specialties, prefer the 24-hour working day, and reli eve their stress with alcohol and sports. Surgeons have moderate level of PBS, emotional exhaustion, low degree of cynicism, moderate desire for career growth, frequent misunderstandings with their colleagues of related specialties, prefer the 8-hour working day, and relieve stress by smoking and sleeping. PBS is most expressed in doctors having working experience of 11 to 15 years and in anesthesiologists. They get professional deformations. These features should be considered in course of organization of working process of medical teams.

  18. Heuristic Optimization Techniques for Determining Optimal Reserve Structure of Power Generating Systems

    DEFF Research Database (Denmark)

    Ding, Yi; Goel, Lalit; Wang, Peng

    2012-01-01

    cost of the system will also increase. The reserve structure of a MSS should be determined based on striking a balance between the required reliability and the reserve cost. The objective of reserve management for a MSS is to schedule the reserve at the minimum system reserve cost while maintaining......Electric power generating systems are typical examples of multi-state systems (MSS). Sufficient reserve is critically important for maintaining generating system reliabilities. The reliability of a system can be increased by increasing the reserve capacity, noting that at the same time the reserve...... the required level of supply reliability to its customers. In previous research, Genetic Algorithm (GA) has been used to solve most reliability optimization problems. However, the GA is not very computationally efficient in some cases. In this chapter a new heuristic optimization technique—the particle swarm...

  19. THD Minimization from H-Bridge Cascaded Multilevel Inverter Using Particle Swarm Optimization Technique

    Directory of Open Access Journals (Sweden)

    MUDASIR AHMED MEMON

    2017-01-01

    Full Text Available In this paper, PSO (Particle Swarm Optimization based technique is proposed to derive optimized switching angles that minimizes the THD (Total Harmonic Distortion and reduces the effect of selected low order non-triple harmonics from the output of the multilevel inverter. Conventional harmonic elimination techniques have plenty of limitations, and other heuristic techniques also not provide the satisfactory results. In this paper, single phase symmetrical cascaded H-Bridge 11-Level multilevel inverter is considered, and proposed algorithm is utilized to obtain the optimized switching angles that reduced the effect of 5th, 7th, 11th and 13th non-triplen harmonics from the output voltage of the multilevel inverter. A simulation result indicates that this technique outperforms other methods in terms of minimizing THD and provides high-quality output voltage waveform.

  20. THD minimization from h-bridge cascaded multilevel inverter using particle swarm optimization technique

    International Nuclear Information System (INIS)

    Memon, M.A.; Memon, S.; Khan, S.

    2017-01-01

    In this paper, PSO (Particle Swarm Optimization) based technique is proposed to derive optimized switching angles that minimizes the THD (Total Harmonic Distortion) and reduces the effect of selected low order non-triple harmonics from the output of the multilevel inverter. Conventional harmonic elimination techniques have plenty of limitations, and other heuristic techniques also not provide the satisfactory results. In this paper, single phase symmetrical cascaded H-Bridge 11-Level multilevel inverter is considered, and proposed algorithm is utilized to obtain the optimized switching angles that reduced the effect of 5th, 7th, 11th and 13th non-triplen harmonics from the output voltage of the multilevel inverter. A simulation result indicates that this technique outperforms other methods in terms of minimizing THD and provides high-quality output voltage waveform. (author)

  1. Resizing Technique-Based Hybrid Genetic Algorithm for Optimal Drift Design of Multistory Steel Frame Buildings

    Directory of Open Access Journals (Sweden)

    Hyo Seon Park

    2014-01-01

    Full Text Available Since genetic algorithm-based optimization methods are computationally expensive for practical use in the field of structural optimization, a resizing technique-based hybrid genetic algorithm for the drift design of multistory steel frame buildings is proposed to increase the convergence speed of genetic algorithms. To reduce the number of structural analyses required for the convergence, a genetic algorithm is combined with a resizing technique that is an efficient optimal technique to control the drift of buildings without the repetitive structural analysis. The resizing technique-based hybrid genetic algorithm proposed in this paper is applied to the minimum weight design of three steel frame buildings. To evaluate the performance of the algorithm, optimum weights, computational times, and generation numbers from the proposed algorithm are compared with those from a genetic algorithm. Based on the comparisons, it is concluded that the hybrid genetic algorithm shows clear improvements in convergence properties.

  2. A CMOS-compatible silicon substrate optimization technique and its application in radio frequency crosstalk isolation

    International Nuclear Information System (INIS)

    Li Chen; Liao Huailin; Huang Ru; Wang Yangyuan

    2008-01-01

    In this paper, a complementary metal-oxide semiconductor (CMOS)-compatible silicon substrate optimization technique is proposed to achieve effective isolation. The selective growth of porous silicon is used to effectively suppress the substrate crosstalk. The isolation structures are fabricated in standard CMOS process and then this post-CMOS substrate optimization technique is carried out to greatly improve the performances of crosstalk isolation. Three-dimensional electro-magnetic simulation is implemented to verify the obvious effect of our substrate optimization technique. The morphologies and growth condition of porous silicon fabricated have been investigated in detail. Furthermore, a thick selectively grown porous silicon (SGPS) trench for crosstalk isolation has been formed and about 20dB improvement in substrate isolation is achieved. These results demonstrate that our post-CMOS SGPS technique is very promising for RF IC applications. (cross-disciplinary physics and related areas of science and technology)

  3. Supraretinacular endoscopic carpal tunnel release: surgical technique with prospective case series.

    Science.gov (United States)

    Ecker, J; Perera, N; Ebert, J

    2015-02-01

    Current techniques for endoscopic carpal tunnel release use an infraretinacular approach, inserting the endoscope deep to the flexor retinaculum. We present a supraretinacular endoscopic carpal tunnel release technique in which a dissecting endoscope is inserted superficial to the flexor retinaculum, which improves vision and the ability to dissect and manipulate the median nerve and tendons during surgery. The motor branch of the median nerve and connections between the median and ulnar nerve can be identified and dissected. Because the endoscope is inserted superficial to the flexor retinaculum, the median nerve is not compressed before division of the retinaculum and, as a result, we have observed no cases of the transient median nerve deficits that have been reported using infraretinacular endoscopic techniques. © The Author(s) 2014.

  4. Mechanoluminescence assisting agile optimization of processing design on surgical epiphysis plates

    Science.gov (United States)

    Terasaki, Nao; Toyomasu, Takashi; Sonohata, Motoki

    2018-04-01

    We propose a novel method for agile optimization of processing design by visualization of mechanoluminescence. To demonstrate the effect of the new method, epiphysis plates were processed to form dots (diameters: 1 and 1.5 mm) and the mechanical information was evaluated. As a result, the appearance of new strain concentration was successfully visualized on the basis of mechanoluminescence, and complex mechanical information was instinctively understood by surgeons as the designers. In addition, it was clarified by mechanoluminescence analysis that small dots do not have serious mechanical effects such as strength reduction. Such detail mechanical information evaluated on the basis of mechanoluminescence was successfully applied to the judgement of the validity of the processing design. This clearly proves the effectiveness of the new methodology using mechanoluminescence for assisting agile optimization of the processing design.

  5. An adaptive dual-optimal path-planning technique for unmanned air vehicles

    Directory of Open Access Journals (Sweden)

    Whitfield Clifford A.

    2016-01-01

    Full Text Available A multi-objective technique for unmanned air vehicle path-planning generation through task allocation has been developed. The dual-optimal path-planning technique generates real-time adaptive flight paths based on available flight windows and environmental influenced objectives. The environmentally-influenced flight condition determines the aircraft optimal orientation within a downstream virtual window of possible vehicle destinations that is based on the vehicle’s kinematics. The intermittent results are then pursued by a dynamic optimization technique to determine the flight path. This path-planning technique is a multi-objective optimization procedure consisting of two goals that do not require additional information to combine the conflicting objectives into a single-objective. The technique was applied to solar-regenerative high altitude long endurance flight which can benefit significantly from an adaptive real-time path-planning technique. The objectives were to determine the minimum power required flight paths while maintaining maximum solar power for continual surveillance over an area of interest (AOI. The simulated path generation technique prolonged the flight duration over a sustained turn loiter flight path by approximately 2 months for a year of flight. The potential for prolonged solar powered flight was consistent for all latitude locations, including 2 months of available flight at 60° latitude, where sustained turn flight was no longer capable.

  6. Two Techniques of Intestinal Wall Suture in Surgical Treatment of Ileus in Dogs and the Importance of Omentalisation

    Directory of Open Access Journals (Sweden)

    M. Crha

    2008-01-01

    Full Text Available Model experimental studies focused on the intestinal suture techniques in relation to healing, postoperative narrowing of the intestinal lumen or adhesion formation can not comprise a number of clinical factors (foreign body presence in the intestine, haematological abnormalities, septic peritonitis, different age of patients, etc. that under clinical practice conditions may have an effect on the healing of the intestinal suture. The aim of this clinical study was to confirm in a group of dogs surgically treated for small bowel obstruction, whether different techniques of its wall suture may affect the frequency of possible dehiscence occurrence. This study compares two different techniques of intestinal wall suture in relation to postoperative dehiscence of the intestinal wall closure. Based on the clinical observation with regard to the risk of postoperative dehiscence and possible complications in form of adhesions, also the importance of omentalisation in the suture of small bowel was evaluated. No significant difference was demonstrated (p > 0.05 in the frequency of postoperative dehiscence at the site of the intestinal wall closure between the two-layer inverting and singlelayer appositional techniques of suture. Likewise, no significant difference was demonstrated (p > 0.05 in the frequency of dehiscence of intestinal wall suture between patients that underwent intestinal suture omentalisation and those whose intestinal wall suture was not complemented with omentalisation. Based on the results of this clinical study it may be stated that both manual single-layer approximation technique and two-layer inverting technique of the intestinal wall suture are equally safe from the viewpoint of possible dehiscence, and it depends on the surgeon's preference, which one of the said techniques he or she chooses. Concurrently it may be assumed that an exactly performed suture of the intestinal wall does not necessarily require omentalisation.

  7. [A new technique for ensuring negative surgical margins during partial nephrectomy: the ex vivo ultrasound control].

    Science.gov (United States)

    Desmonts, A; Tillou, X; Le Gal, S; Secco, M; Orczyk, C; Bensadoun, H; Doerfler, A

    2013-10-01

    To evaluate the feasibility and the efficiency of intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy by urologist. Patients undergoing partial nephrectomy from July 2010 to November 2012 for T1-T2 renal tumors were included in analysis. Tumor margin status was immediately determined by ex vivo ultrasound done by the surgeon himself. Results were compared with margin status on definitive pathological evaluation. A total of 26 men and 15 women with a median age of 61 (30-82) years old were included in analysis. Intraoperative ex vivo ultrasound revealed negative surgical margins in 38 cases and positive margins in two. Final pathological results revealed negative margins in all except one case. Ultrasound sensitivity and specificity were 100% and 97%, respectively. Mean ultrasound duration was 1minute±1. Mean tumor and margin sizes were 3.4±1.8cm and 2.38±1.76mm, respectively. Intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy by a urologist seemed to be feasible, efficient and easy. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. [Pay attention to the standardized application of new techniques in surgical treatment of thyroid disease].

    Science.gov (United States)

    Tian, W; Xi, H Q; Wang, B

    2017-08-01

    The continuous development and application of new technology in thyroid surgery has promoted the rapid improvement of thyroid surgery. New technology in the field of thyroid surgery has developed rapidly. The application of neural monitoring technology has enabled the thyroid surgery to enter an accurate era. Imtraoperative neuromonitoring and continuous intraoperative neuromonitoring have made the recurrent laryngeal nerve protection more secure. Nano-carbon parathyroid gland negative imaging technology could identify parathyroid gland more precise. However, when the nano-carbon was used, the injection time, position and dosage should be grasped so as to achieve the best effect of negative imaging. Endoscopic and robotic thyroid surgery could meet the demand of cosmetic. "Treatment first, beauty second" is still the principle to be strictly followed. Do not blindly expand indications and pursue endoscopic surgery. Energy surgical instruments' update made the operation more efficient, while the instruments have some disadvantages. Thyroid surgeon must correctly understand the working principle of new energy devices and use them rationally. Through grasping the working principle and application skills of new technology in clinical work, definiting its advantages and disadvantages, adhereing to the "reasonable choice, standard application" principle, learning the pioneers' experience, the application of new thyroid diagnosis and treatment technology could be more reasonable and safe.

  9. Numerical Methods Are Feasible for Assessing Surgical Techniques: Application to Astigmatic Keratotomy

    Energy Technology Data Exchange (ETDEWEB)

    Ariza-Gracia, M.A.; Ortilles, A.; Cristobal, J.A.; Rodriguez, J.F.; Calvo, B.

    2016-07-01

    The present study proposes an experimental-numerical protocol whose novelty relies on using both the inflation and the indentation experiments simultaneously to obtain a set of material parameters which accounts for both deformation modes of the cornea: the physiological (biaxial tension) and the non-physiological (bending). The experimental protocol characterizes the corneal geometry and the mechanical response of the cornea when subjected to the experimental tests using an animal model (New Zealand rabbit's cornea). The numerical protocol reproduces the experimental tests by means of an inverse finite element methodology to obtain the set of material properties that minimizes both mechanical responses at the same time. To validate the methodology, an Astigmatic Keratotomy refractive surgery is performed on 4 New Zealand rabbit corneas. The pre and post-surgical topographies of the anterior corneal surface were measured using a MODI topographer (CSO, Italy) to control the total change in astigmatism. Afterwards, the surgery is numerically reproduced to predict the overall change of the cornea. Results showed an acceptable numerical prediction, close to the average experimental correction, validating the material parameters obtained with the proposed protocol. (Author)

  10. Journal of Surgical Technique and Case Report - Vol 5, No 1 (2013)

    African Journals Online (AJOL)

    A Simple Technique for Adjustment of the Femoral Offset at the Site of Hip Spacer Implantation · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. K Anagnostakos, O Lorbach, P Orth, K Koch, 18-20. http://dx.doi.org/10.4103/2006-8808.118605 ...

  11. Surgical Management of Large Periorbital Cutaneous Defects: Aesthetic Considerations and Technique Refinements.

    Science.gov (United States)

    Zou, Yun; Hu, Li; Tremp, Mathias; Jin, Yunbo; Chen, Hui; Ma, Gang; Lin, Xiaoxi

    2018-02-23

    The aim of this study was to repair large periorbital cutaneous defects by an innovative technique called PEPSI (periorbital elevation and positioning with secret incisions) technique with functional and aesthetic outcomes. In this retrospective study, unilateral periorbital cutaneous defects in 15 patients were repaired by the PEPSI technique. The ages of patients ranged from 3 to 46 years (average, 19 years). The outcome evaluations included scars (Vancouver Scar Scale and visual analog scale score), function and aesthetic appearance of eyelids, and patient satisfaction. The repair size was measured by the maximum advancement distance of skin flap during operation. All patients achieved an effective repair with a mean follow-up of 18.3 months. Except one with a small (approximately 0.3 cm) necrosis, all patients healed with no complication. The mean Vancouver Scar Scale and visual analog scale scores were 2.1 ± 1.7 and 8.5 ± 1.2, respectively. Ideal cosmetic and functional outcomes were achieved in 14 patients (93.3%). All patients achieved complete satisfaction except 1 patient with partial satisfaction. The mean maximum advancement distance of skin flap was 20.2 mm (range, 8-50 mm). This study demonstrated that the PEPSI technique is an effective method to repair large periorbital cutaneous defects with acceptable functional and aesthetic outcomes.

  12. Biological limits of the undersized surgical technique: a study in goats

    NARCIS (Netherlands)

    Tabassum, A.; Meijer, G.J.; Walboomers, X.F.; Jansen, J.A.

    2011-01-01

    OBJECTIVE: The purpose of the present study was to investigate the influence of different implant placement techniques on the early bone healing response in an animal model. MATERIAL AND METHODS: In the present study, 24 cylindrical-screw-type implants with a diameter of 4.2 mm (Dyna(R)) were

  13. Comparison of various spring analogy related mesh deformation techniques in two-dimensional airfoil design optimization

    Science.gov (United States)

    Yang, Y.; Özgen, S.

    2017-06-01

    During the last few decades, CFD (Computational Fluid Dynamics) has developed greatly and has become a more reliable tool for the conceptual phase of aircraft design. This tool is generally combined with an optimization algorithm. In the optimization phase, the need for regenerating the computational mesh might become cumbersome, especially when the number of design parameters is high. For this reason, several mesh generation and deformation techniques have been developed in the past decades. One of the most widely used techniques is the Spring Analogy. There are numerous spring analogy related techniques reported in the literature: linear spring analogy, torsional spring analogy, semitorsional spring analogy, and ball vertex spring analogy. This paper gives the explanation of linear spring analogy method and angle inclusion in the spring analogy method. In the latter case, two di¨erent solution methods are proposed. The best feasible method will later be used for two-dimensional (2D) Airfoil Design Optimization with objective function being to minimize sectional drag for a required lift coe©cient at di¨erent speeds. Design variables used in the optimization include camber and thickness distribution of the airfoil. SU2 CFD is chosen as the §ow solver during the optimization procedure. The optimization is done by using Phoenix ModelCenter Optimization Tool.

  14. Comparative evaluation of gingival depigmentation by tetrafluroethane cryosurgery and surgical scalpel technique. A randomized clinical study

    Directory of Open Access Journals (Sweden)

    Suraj D Narayankar

    2017-01-01

    Full Text Available Introduction: Importance of good smile cannot be underestimated in enhancement of beauty, self-confidence and personality of a person. Health and appearance of gingiva is an essential part of attractive smile. Gingival pigmentation gives rise to unesthetic smile line. In present world, with increasing awareness to esthetic, people have become highly concerned about black gums. Various treatment modalities like abrasion, scrapping, scalpel technique, cryosurgery, electrosurgery and laser are available for treatment of gingival pigmentation. The present study was conducted with an objective of comparing efficacy of gingival depigmentation by cryosurgery and scalpel technique. Method: A Randomized control split mouth study was conducted for 25 patients with gingival pigmentation. Gingival pigmentation Index (GPI for pigmentation and Visual Analoug Scale (VAS for pain was evaluated for both test (Cryosurgery and control sites (Scalpel technique at baseline, 1month, 3months and 6 months. Results: GPI score was 3 and 2 for 21/25 and 4/25 control sites and was 22/25 and 3/25 test sites respectively at baseline. Both the groups showed significant reduction in GPI score i.e., 0 at 1 and 3 months interval after treatment. GPI score increased to 1 for 5/25 sites treated with scalpel technique and 2/25 sites treated with cryosurgery at 6 months interval (P=0.0691. This indicates recurrence rate for pigmentation is higher after scalpel treatment. VAS Score was 3 for 10/25 sites treated with scalpel and was 2 for 12/25 sites treated with cryosurgery (P<0.001. Conclusion: It can be concluded that cryosurgery can be effectively and efficiently used for depigmentation by keeping patients acceptance and comfort in mind and also the long term results and ease of use when compared to scalpel technique.

  15. A classification system of intraocular lens dislocation sites under operating microscopy, and the surgical techniques and outcomes of exchange surgery.

    Science.gov (United States)

    Hayashi, Ken; Ogawa, Soichiro; Manabe, Shin-Ichi; Hirata, Akira; Yoshimura, Koichi

    2016-03-01

    The aim of this study was to examine the recent status of intraocular lens (IOL) dislocation according to a classification system based on vertical dislocation position, as well as the surgical techniques and outcomes of IOL exchange surgery. The medical records of 230 eyes from 214 consecutive patients who experienced IOL dislocation and underwent exchange surgery between 2006 and 2014 were reviewed. Vertical dislocation sites observed preoperatively under operating microscopy were examined, along with the surgical techniques and outcomes of IOL exchange. Dislocation sites included (1) the anterior chamber (12.2 %), (2) pseudophakodonesis (19.1 %), (3) the anterior vitreous cavity (47.4 %), (4) trap door-like dislocation (dangling in the peripheral vitreous cavity; 16.1 %), and (5) the retinal surface (5.2 %). The IOL retained in the anterior segment was moved onto the iris by pulling it up through the limbal side ports with an anterior vitrectomy (67.8 %), or by pushing it up from the pars plana with an anterior vitrectomy (26.5 %), while the IOL dropped on the retina was lifting it up from the retina after pars plana vitrectomy (5.7 %). Mean uncorrected and distance-corrected visual acuity significantly improved postoperatively (p system, approximately 95 % of dislocated IOLs were retained in the anterior segment, and these IOLs were exchanged using an anterior approach through limbal incisions with an anterior vitrectomy. Visual acuity improved significantly, and serious complications were uncommon, probably because the IOL exchange techniques were standardized and simplified without pars plana vitrectomy.

  16. Three-Dimensional Implant Positioning with a Piezosurgery Implant Site Preparation Technique and an Intraoral Surgical Navigation System: Case Report.

    Science.gov (United States)

    Pellegrino, Gerardo; Taraschi, Valerio; Vercellotti, Tomaso; Ben-Nissan, Besim; Marchetti, Claudio

    This case report describes new implant site preparation techniques joining the benefits of using an intraoral navigation system to optimize three-dimensional implant site positioning in combination with an ultrasonic osteotomy. A report of five patients is presented, and the implant positions as planned in the navigation software with the postoperative scan image were compared. The preliminary results are useful, although further clinical studies with larger populations are needed to confirm these findings.

  17. Comparison of optimization techniques for MRR and surface roughness in wire EDM process for gear cutting

    Directory of Open Access Journals (Sweden)

    K.D. Mohapatra

    2016-11-01

    Full Text Available The objective of the present work is to use a suitable method that can optimize the process parameters like pulse on time (TON, pulse off time (TOFF, wire feed rate (WF, wire tension (WT and servo voltage (SV to attain the maximum value of MRR and minimum value of surface roughness during the production of a fine pitch spur gear made of copper. The spur gear has a pressure angle of 20⁰ and pitch circle diameter of 70 mm. The wire has a diameter of 0.25 mm and is made of brass. Experiments were conducted according to Taguchi’s orthogonal array concept with five factors and two levels. Thus, Taguchi quality loss design technique is used to optimize the output responses carried out from the experiments. Another optimization technique i.e. desirability with grey Taguchi technique has been used to optimize the process parameters. Both the optimized results are compared to find out the best combination of MRR and surface roughness. A confirmation test was carried out to identify the significant improvement in the machining performance in case of Taguchi quality loss. Finally, it was concluded that desirability with grey Taguchi technique produced a better result than the Taguchi quality loss technique in case of MRR and Taguchi quality loss gives a better result in case of surface roughness. The quality of the wire after the cutting operation has been presented in the scanning electron microscopy (SEM figure.

  18. Optimization of freeform surfaces using intelligent deformation techniques for LED applications

    Science.gov (United States)

    Isaac, Annie Shalom; Neumann, Cornelius

    2018-04-01

    For many years, optical designers have great interests in designing efficient optimization algorithms to bring significant improvement to their initial design. However, the optimization is limited due to a large number of parameters present in the Non-uniform Rationaly b-Spline Surfaces. This limitation was overcome by an indirect technique known as optimization using freeform deformation (FFD). In this approach, the optical surface is placed inside a cubical grid. The vertices of this grid are modified, which deforms the underlying optical surface during the optimization. One of the challenges in this technique is the selection of appropriate vertices of the cubical grid. This is because these vertices share no relationship with the optical performance. When irrelevant vertices are selected, the computational complexity increases. Moreover, the surfaces created by them are not always feasible to manufacture, which is the same problem faced in any optimization technique while creating freeform surfaces. Therefore, this research addresses these two important issues and provides feasible design techniques to solve them. Finally, the proposed techniques are validated using two different illumination examples: street lighting lens and stop lamp for automobiles.

  19. Optimization of surgical treatment of cataract in patients with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Dmitriy Valentinovich Lipatov

    2010-06-01

    Full Text Available Aim. To compare different methods for surgical treatment of cataract in patients with diabetes melli-tus (DM and substantiate the choice of its optimalmodality. Materials and methods. Analysis included data on 209 patients (221 eyes treated from January 2008 to December 2009 in the Department ofRetinopathy and Ophthalmosurgey, Endocrinological Research Centre. Diabetic cataract was managed using UNIVERSAL-II, LEGACY EVEREST,and INFINITI phacoemulsifiers. Parameters studied included time of ultrasound (US ex-posure, US power, and retinal characteristics in the earlypostoperative period. In addition, analysis included data on the location of lens opacity in 1047 patients (1897 eyes with diabetic cataract. Results. Relatively low corrected and uncorrected visual acuity in the early postoperative period was attributable to concomitant DM-related retinalpathology. Analysis of lenticular opacity showed that it in the first place affected collagen fibers beneath the posterior capsule. The use of torsional USin INFINITI for cataract phacoemulsification produced almost 4-fold reduction in the exposure time of ocular tissues. As a result, the postoperativeoedema was significantly smaller than in patients undergoing combined treatment (AQUALASE hydromonitoring and OZIL ultrasound system. Conclusion. Combination of ultrasound and hydromonitoring phacoemulsification for the treatment of cataract in DM patients reduces exposure timeof ocular tissues and postoperative oedema which creates prerequisites for faster recovery of visual acuity after surgery. Functional results of surgicaltreatment of diabetic cataract can be further improved by early diagnosis of lens opacity and the use of US and hydromonitoring phacoemulsificationtechniques.

  20. Total pancreatectomy and islet autotransplantation in children for chronic pancreatitis: indication, surgical techniques, postoperative management, and long-term outcomes.

    Science.gov (United States)

    Chinnakotla, Srinath; Bellin, Melena D; Schwarzenberg, Sarah J; Radosevich, David M; Cook, Marie; Dunn, Ty B; Beilman, Gregory J; Freeman, Martin L; Balamurugan, A N; Wilhelm, Josh; Bland, Barbara; Jimenez-Vega, Jose M; Hering, Bernhard J; Vickers, Selwyn M; Pruett, Timothy L; Sutherland, David E R

    2014-07-01

    Describe the surgical technique, complications, and long-term outcomes of total pancreatectomy and islet autotransplantation (TP-IAT) in a large series of pediatric patients. Surgical management of childhood pancreatitis is not clear; partial resection or drainage procedures often provide transient pain relief, but long-term recurrence is common due to the diffuse involvement of the pancreas. Total pancreatectomy (TP) removes the source of the pain, whereas islet autotransplantation (IAT) potentially can prevent or minimize TP-related diabetes. Retrospective review of 75 children undergoing TP-IAT for chronic pancreatitis who had failed medical, endoscopic, or surgical treatment between 1989 and 2012. Pancreatitis pain and the severity of pain statistically improved in 90% of patients after TP-IAT (P Puestow procedure (P = 0.018), lower body surface area (P = 0.048), higher islet equivalents (IEQ) per kilogram body weight (P = 0.001), and total IEQ (100,000) (P = 0.004) were associated with insulin independence. By multivariate analysis, 3 factors were associated with insulin independence after TP-IAT: (1) male sex, (2) lower body surface area, and (3) higher total IEQ per kilogram body weight. Total IEQ (100,000) was the single factor most strongly associated with insulin independence (odds ratio = 2.62; P < 0.001). Total pancreatectomy and islet autotransplantation provides sustained pain relief and improved quality of life. The β-cell function is dependent on islet yield. Total pancreatectomy and islet autotransplantation is an effective therapy for children with painful pancreatitis that failed medical and/or endoscopic management.

  1. Esthetic judgments of palatally displaced canines 3 months postdebond after surgical exposure with either a closed or an open technique.

    Science.gov (United States)

    Parkin, Nicola A; Freeman, Jennifer V; Deery, Chris; Benson, Philip E

    2015-02-01

    The aim of this study was to compare the esthetic judgments of orthodontists and laypeople regarding the appearance of palatally displaced canines 3 months after treatment with either a closed or an open surgical exposure and orthodontic alignment. A multicenter randomized controlled trial was undertaken in 3 hospitals in the United Kingdom. Patients with unilateral palatally displaced canines were randomly allocated to receive either a closed or an open surgical exposure. The teeth were aligned with fixed appliances, and 3 months after debond, intraoral photographs were taken. The photographs were projected in random order to 2 panels of judges (orthodontists and laypeople), who completed a questionnaire. The images of 67 participants (closed, 33; open, 34) were included. The laypeople were able to identify the operated tooth only 49.7% of the time (95% CI, 45.3%-54.0%); this was no better than chance (P = 0.880). The orthodontists were more successful but still identified the treated canine with certainty only 60.7% of the time (95% CI, 53.7%-67.8%; P = 0.003). Both panels more frequently assessed the unoperated canine to have a better appearance than the contralateral operated canine; however, there were no differences between the closed and open groups (proportion preferring unoperated canine-laypeople: closed, 58.7%; open, 57.0%; P = 0.43; and orthodontists: closed, 60.9%; open, 60.6%; P = 0.27). There is an esthetic impact to aligning a palatally displaced canine, but it is mostly minor and unlikely to be detectable by laypeople. The esthetic impact was the same, whether the canine was exposed with a closed or an open surgical technique. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  2. Acetabular osteotomy for double boarding in lateral decubitus. Anatomical bases and surgical technique

    International Nuclear Information System (INIS)

    Lazennec, J Y; Del Vecchio, R; Saillant, G

    2001-01-01

    The periacetabular osteotomies of reorientation of the eotilo have a reputation of being difficult from the technical point of view. The authors present a technique of juxta acetabular osteotomy that respects the posterior column of the acetabulo the same as the GANZ technique. The osteotomy is of simpler realization thanks to an installation that allows carrying out two simultaneous boarding. The osteotomy lines, their rectilinear and controllable in permanency through of images intensificator and they don't constitute any risk for the essential vascular contribution of the obturatriz artery and their branches. Their other interest comes represented by the possibility of correcting easily the parasitic retroversion associated to the descent of the whole eotilo, that it allows to avoid the bad positions that they affect the center of the articulation and the widths acetabular

  3. Surgical technique for permanent intracoelomic radiotransmitter placement in Anegada iguanas (Cyclura pinguis).

    Science.gov (United States)

    Ferrell, Shannon T; Marlar, Annajane B; Alberts, Allison C; Young, Lee A; Bradley, Kelly; Hurlbut, Sandra L; Lung, Nancy P

    2005-12-01

    Twenty-four juvenile to subadult Anegada iguanas (Cyclura pinguis), captive-reared in a propagation facility, were designated by a coordinated recovery program for release in the summer of 2003. To facilitate postrelease monitoring, a radiotransmitter device was placed within the coelomic cavity of each animal under general anesthesia before release. The equipment sterilization technique and the method of attachment of the transmitters to the coelomic body wall resulted in functional transmitters and acceptably low rates of mortality associated with the procedure.

  4. Shoulder arthroplasty in osteoarthritis: current concepts in biomechanics and surgical technique

    Science.gov (United States)

    Merolla, G; Nastrucci, G; Porcellini, G

    Shoulder arthroplasty is a technically demanding procedure to restore shoulder function in patients with severe osteoarthritis of the glenohumeral joint. The modern prosthetic system exploit the benefits of modularity and the availibility of additional sizes of the prosthetic components. In this paper we describe the biomechanics of shoulder arthroplasty and the technique for shoulder replacement including total shoulder arthroplasty (TSA) with all-polyethylene and metal-backed glenoid component, humeral head resurfacing and stemless humeral replacement. PMID:24251240

  5. Unstable elbow dislocations: the description and cadaveric feasibility study of a new surgical technique

    Directory of Open Access Journals (Sweden)

    Harris Mark

    2015-01-01

    Full Text Available Introduction: A small proportion of simple elbow dislocations are grossly unstable and joint congruence is not maintained after reduction. In this rare situation operative treatment is indicated. We describe a new intra articular reconstruction that utilises a slip of triceps tendon to provide immediate stability to the elbow. Methods: We assessed 20 cadaveric elbows, measuring the length of triceps tendon available and required to complete the reconstruction. We then sequentially sectioned the ligamentous stabilisers of an elbow before performing the new technique. We measured the displacement and angulation possible at the elbow before and after the reconstruction. Results: All 20 elbows had sufficient triceps tendon length to complete the new technique. Prior to the reconstruction greater than 30 mm of joint distraction and 90 degrees varus or valgus angulation was possible. Following the reconstruction it was not possible to re-dislocate the elbow. Only 2 mm of joint distraction and 10 degrees of varus or valgus angulation were possible with the triceps graft fixed in position. Discussion: This novel technique elegantly avoids many of the problems associated with current methods. We have demonstrated that it is technically feasible and easy to perform with minimal equipment requirements or costs.

  6. Limbal Stem Cell-Sparing Corneoscleroplasty with Peripheral Intralamellar Tuck: A New Surgical Technique for Keratoglobus

    Directory of Open Access Journals (Sweden)

    Elias Jarade

    2017-04-01

    Full Text Available Purpose: To describe the technique of limbal stem cell-sparing corneoscleroplasty for the management of advanced keratoglobus. Methods: A patient with bilateral advanced keratoglobus, with best-corrected visual acuity of 20/400 in the right eye and 20/200 in the left eye, underwent limbal stem cell-sparing corneoscleroplasty of the right eye. Initially, a 360-degree limbal incision with 200-μm depth was created, followed by a sublimbal tunnel dissection into the sclera, in order to conserve stem cells. Next, a limbus-to-limbus lamellar keratectomy at 200-μm depth was performed. Meanwhile, a donor corneoscleral button with preserved endothelium of the central 8 mm was fashioned. Prior to suturing the donor corneoscleral graft using a modified suturing technique to cover its scleral component, a full-thickness trephination of 8-mm diameter was completed in the central host cornea. Results: Reepithelialization occurred within the first week. No episodes of rejection, intraocular pressure spikes, or epithelial breakdown were observed postoperatively. At the 6-month follow-up, the patient had 20/70 best-corrected vision and a smooth cornea with regular astigmatism on topography. Conclusion: Limbal stem cell-sparing corneoscleroplasty is a single-step technique for restoring the structural integrity of the cornea in advanced keratoglobus while preserving the host limbal stem cells.

  7. Robust design of decentralized power system stabilizers using meta-heuristic optimization techniques for multimachine systems

    Directory of Open Access Journals (Sweden)

    Jeevanandham Arumugam

    2009-01-01

    Full Text Available In this paper a classical lead-lag power system stabilizer is used for demonstration. The stabilizer parameters are selected in such a manner to damp the rotor oscillations. The problem of selecting the stabilizer parameters is converted to a simple optimization problem with an eigen value based objective function and it is proposed to employ simulated annealing and particle swarm optimization for solving the optimization problem. The objective function allows the selection of the stabilizer parameters to optimally place the closed-loop eigen values in the left hand side of the complex s-plane. The single machine connected to infinite bus system and 10-machine 39-bus system are considered for this study. The effectiveness of the stabilizer tuned using the best technique, in enhancing the stability of power system. Stability is confirmed through eigen value analysis and simulation results and suitable heuristic technique will be selected for the best performance of the system.

  8. Studies Regarding Design and Optimization of Mechanisms Using Modern Techniques of CAD and CAE

    Directory of Open Access Journals (Sweden)

    Marius Tufoi

    2010-01-01

    Full Text Available The paper presents applications of modern techniques of CAD (Computer Aided Design and CAE (Computer Aided Engineering to design and optimize the mechanisms used in mechanical engineering. The use exemplification of these techniques was achieved by designing and optimizing parts of a drawing installation for horizontal continuous casting of metals. By applying these design methods and using finite element method at simulations on designed mechanisms results a number of advantages over traditional methods of drawing and design: speed in drawing, design and optimization of parts and mechanisms, kinematic analysis option, kinetostatic and dynamic through simulation, without requiring physical realization of the part or mechanism, the determination by finite element method of tension, elongations, travel and safety factor and the possibility of optimization for these sizes to ensure the mechanical strength of each piece separately. Achieving these studies was possible using SolidWorks 2009 software suite.

  9. The Demographics of Patients with Skin Cancer who Underwent Surgery in Diyarbakır and Performed Surgical Techniques

    Directory of Open Access Journals (Sweden)

    Burhan Özalp

    2018-06-01

    Full Text Available Objective: The major factor for developing malignant skin cancers is sunlight exposure. This study aimed to evaluate the demographics of patients with skin cancers who underwent surgery in Diyarbakır where the population is exposed to more sunlight than most other Turkish cities. Methods: The medical records of patients who underwent surgery for malignant skin cancer excision between 2011 and 2016 were searched using University Hospital’s patient database program. Data about patients’ demographics, cancer features, and the surgical techniques performed were collected. Results: Over a 5-year period, 190 patients underwent surgical excision. The male to female ratio was 1.56, and the mean age was 65.8 ± 15.7 (range, 20-94 years. The most common skin cancer was basal cell carcinoma (n=138, 72.7%, followed by squamous cell carcinoma (n=45, 23.7% and malignant melanoma (n=5, 2.6%. The most common surgery was primary excision, which was performed in 90 of 190 patients (47.36%; tissue reconstruction with a skin graft or flap surgery was required for the remaining 100 (52.63%, showing a significant difference (p<0.001. Conclusion: Basal cell carcinoma is the most common skin cancer, and less than half of the patients sought treatment immediately after they recognized the lesion. The public should be educated about skin cancers to increase early diagnosis and encourage timely treatment, thereby decreasing morbidity and mortality from skin cancer.

  10. Current surgical treatment option, utilizing robot-assisted laparoscopic surgery in obese women with endometrial cancer: Farghalys technique

    International Nuclear Information System (INIS)

    Farghaly, S.A.

    2013-01-01

    Background: Endometrial cancer is the most prevalent cancer of the female genital tract in North America. Minimally invasive laparoscopic-assisted surgery and panniculectomy in obese women with endometrial cancer are associated with an improved lymph node count, and lower rate of incisional complications than laparotomy. Methods: Technique for robot-assisted laparoscopic surgery for obese women with endometrial cancer is detailed. Results: Robot-assisted laparoscopic surgical staging, pelvic and para-aortic lymphadenectomy and panniculectomy allow us to avoid the use of postoperative pelvic radiation which is recommended in women with histopathology high-risk findings: deep myometrial invasion or high grade histology. The procedure has the advantage of three-dimensional vision, ergonomic, intuitive control, and wristed instrument that approximate the motion of the human hand. Conclusion: Robot-assisted laparoscopic surgical staging, and panniculectomy in these patients are a safe, and effective alternative to laparoscopic, and laparotomy surgery. It is an ideal tool for performing the complex oncologic procedures encountered in endometrial cancer staging that requires delicate retroperitoneal, pelvic and para-aortic lymph node dissection, while maintaining the principles of oncologic surgery but in a minimally invasive fashion.

  11. Optimizing Patient Surgical Management Using WhatsApp Application in the Italian Healthcare System.

    Science.gov (United States)

    Nardo, Bruno; Cannistrà, Marco; Diaco, Vincenzo; Naso, Agostino; Novello, Matteo; Zullo, Alessandra; Ruggiero, Michele; Grande, Raffaele; Sacco, Rosario

    2016-09-01

    Smartphones changed the method by which doctors communicate with each other, offer modern functionalities sensitive to the context of use, and can represent a valuable ally in the healthcare system. Studies have shown that WhatsApp™ application can facilitate communication within the healthcare team and provide the attending physician a constant oversight of activities performed by junior team members. The aim of the study was to use WhatsApp between two distant surgical teams involved in a program of elective surgery to verify if it facilitates communication, enhances learning, and improves patient care preserving their privacy. We conducted a focused group of surgeons over a 28-month period (from March 2013 to July 2015), and from September 2014 to July 2015, a group of selected specialists communicated healthcare matters through the newly founded "WhatsApp Surgery Group." Each patient enrolled in the study signed a consent form to let the team communicate his/her clinical data using WhatsApp. Communication between team members, response times, and types of messages were evaluated. Forty six (n = 46) patients were enrolled in the study. A total of 1,053 images were used with an average of 78 images for each patient (range 41-143). 125 h of communication were recorded, generating 354 communication events. The expert surgeon had received the highest number of questions (P, 0.001), while the residents asked clinical questions (P, 0.001) and were the fastest responders to communications (P, 0.001). Our study investigated how two distant clinical teams may exploit such a communication system and quantifies both the direction and type of communication between surgeons. WhatsApp is a low cost, secure, and fast technology and it offers the opportunity to facilitate clinical and nonclinical communications, enhance learning, and improve patient care preserving their privacy.

  12. Outcome of different oncoplastic surgical (OPs) techniques for centrally located breast cancer (CLBC)

    International Nuclear Information System (INIS)

    Moustafa, A.; Fakhr, I.

    2014-01-01

    Background: Oncoplastic breast surgery is a standard treatment of early breast cancer, offering a balance between good cosmetic outcome and limited risk of locoregional recurrence, by enabling proper resection margins. Aim of study: To present multiple techniques of partial breast reconstruction following the resection of centrally located breast cancer (CLBC) resection. Patients and methods: From January 2011 to August 2014, 21 patients underwent central quadrantectomy for carcinoma of the central region of the breast. Excisions included the nipple/areola complex, in most of the cases, down to the pectoralis fascia with a wide safety margin, and proper axillary management. Oncoplastic approaches included latissimus dorsi flap, inferior pedicle flap, Melon slice, Grisotti and round block techniques. Results: Mean age of patients was 49.5 ± 10.61 years. Tumor size ranged from 1.5 to 4.5 cm. Postoperative pathology revealed a tumor mean safety margin of 2.5± 0.83 cm, with positive axillary lymph nodes in 15 (75.0%) patients. Nineteen (95.0%) patients received postoperative breast radiotherapy, while 9/20 (45.0%) and 3/20 (15.0%) received adjuvant chemotherapy or hormonal therapy, respectively, and only 8/20 (40.0%) patients received both therapies. During a median follow- up period of 14.89 months, neither local nor distant metastasis, were detected. The postoperative cosmetic result evaluated by the patients was excellent in 6/20 patients (30.0%), good in 11/20 patients (55.0%), fair in 3/20 (15.0%) with neither poor nor bad results, with an overall mean of 4.0 ± 0.5 equivalent to 80% satisfaction. Conclusion: Multiple oncoplastic breast surgery techniques can be used for the resection of CLBC with satisfying cosmetic outcomes.

  13. Correlation between histological outcome and surgical cartilage repair technique in the knee: A meta-analysis.

    Science.gov (United States)

    DiBartola, Alex C; Everhart, Joshua S; Magnussen, Robert A; Carey, James L; Brophy, Robert H; Schmitt, Laura C; Flanigan, David C

    2016-06-01

    Compare histological outcomes after microfracture (MF), autologous chondrocyte implantation (ACI), and osteochondral autograft transfer (OATS). Literature review using PubMed MEDLINE, SCOPUS, Cumulative Index for Nursing and Allied Health Literature (CINAHL), and Cochrane Collaboration Library. Inclusion criteria limited to English language studies International Cartilage Repair Society (ICRS) grading criteria for cartilage analysis after ACI (autologous chondrocyte implantation), MF (microfracture), or OATS (osteochondral autografting) repair techniques. Thirty-three studies investigating 1511 patients were identified. Thirty evaluated ACI or one of its subtypes, six evaluated MF, and seven evaluated OATS. There was no evidence of publication bias (Begg's p=0.48). No statistically significant correlation was found between percent change in clinical outcome and percent biopsies showing ICRS Excellent scores (R(2)=0.05, p=0.38). Percent change in clinical outcome and percent of biopsies showing only hyaline cartilage were significantly associated (R(2)=0.24, p=0.024). Mean lesion size and histological outcome were not correlated based either on percent ICRS Excellent (R(2)=0.03, p=0.50) or percent hyaline cartilage only (R(2)=0.01, p=0.67). Most common lesion location and histological outcome were not correlated based either on percent ICRS Excellent (R(2)=0.03, p=0.50) or percent hyaline cartilage only (R(2)=0.01, p=0.67). Microfracture has poorer histologic outcomes than other cartilage repair techniques. OATS repairs primarily are comprised of hyaline cartilage, followed closely by cell-based techniques, but no significant difference was found cartilage quality using ICRS grading criteria among OATS, ACI-C, MACI, and ACI-P. IV, meta-analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. [TVT and TOT for surgical correction of female stress urinary incontinence. Comparison between techniques].

    Science.gov (United States)

    Torres Zambrano, G; Lujan Galán, M; Martín García, C; García Tello, A; Rodríguez García, N; Berenguer Sánchez, A

    2008-10-01

    Retrospective analysis of a series of patients with stress urinary incontinence that underwent surgery in our department, by means of the TVT and TOT techniques. We evaluate post operative continence, considering "cured" the patient with complete continence and "failure" any type of involuntary stress urine leak, independently of its severity registering the time of its appearance. For this purpose we used the Kaplan-Meier analysis comparing both techniques with the Breslow test. Additionally, postoperative complications were evaluated. 128 patients who underwent surgery by TVT (69 patients, 53.9%) and TOT (59 patients, 46.1%). Mean age was 54.4 years for TVT (95% CI 52.0-56.8) and 59 years for TOT (95% CI 55.9-62.1). Mean follow-up time was 18.7 months for TVT (95% CI 15.6-21.9) and 7.4 months for TOT (95% CI 5.8-8.9). Overall continence rate was 86.7%, 88.4% for TVT and 84.7% for TOT The probability of being continent six months after surgery was 89.1% for TVT and 78.2% for TOT (no significant differences, p = 0.31), with almost all failures within the first six months after surgery. TVT was more frecuently associated with urgency symptoms (33.3%, p = 0.001) and urge incontinence (18.8%,p = 0.16), urinary retention (11.6%, p = 0.38), and prevesical hematoma requiring mesh retrieval. Greater post operative pain was observed with TOT (20.3%, p = 0.005). Our results evidence a similar efficacy with both techniques, with the failures appearing over the first months after surgery. Complications of the voiding urgency type are significantly more frequent with TVT.

  15. What is the optimal minimally invasive surgical procedure for endometrial cancer staging in the obese and morbidly obese woman?

    Science.gov (United States)

    Gehrig, Paola A; Cantrell, Leigh A; Shafer, Aaron; Abaid, Lisa N; Mendivil, Alberto; Boggess, John F

    2008-10-01

    Thirty-three percent of U.S. women are either obese or morbidly obese. This is associated with an increased risk of death from all causes and is also associated with an increased risk of endometrial carcinoma. We sought to compare minimally invasive surgical techniques for staging the obese and morbidly obese woman with endometrial cancer. Consecutive robotic endometrial cancer staging procedures were collected from 2005-2007 and were compared to consecutive laparoscopic cases (2000-2004). Demographics including age, weight, body mass index (BMI), operative time, estimated blood loss, lymph node retrieval, hospital stay and complications were collected and compared. During the study period, there were 36 obese and 13 morbidly obese women who underwent surgery with the DaVinci robotic system and 25 obese and 7 morbidly obese women who underwent traditional laparoscopy. For both the obese and morbidly obese patient, robotic surgery was associated with shorter operative time (p=0.0004), less blood loss (ptool for the comprehensive surgical staging of the obese and morbidly obese woman with endometrial cancer. As this patient population is at increased risk of death from all causes, including post-operative complications, all efforts should be made to improve their outcomes and minimally invasive surgery provides a useful platform by which this can occur.

  16. The results of surgical treatment of oviductal infertility with use of microsurgical technique

    International Nuclear Information System (INIS)

    Cislo, M.; Murawski, M.; Palczynski, B.

    1993-01-01

    40 women were operated on infertility due to oviductal factor. This kind of infertility has been previously diagnosed by hysterosalpingography examination and then verified in 22 cases (55%) by laparoscopy combined with chromotubation. The operations were carried out with use of microsurgical technique and instruments. At the same time the prophylactics of postoperative intraperitoneal adhesions was applied. Seven pregnancies were obtained, that makes 17.5% of success. It is an outcome comparable with results presented by many other world centers of gynecological microsurgery. (author)

  17. Lateral high abdominal ovariopexy: an original surgical technique for protection of the ovaries during curative radiotherapy for Hodgkin's disease

    International Nuclear Information System (INIS)

    Gaetini, A.; De Simone, M.; Urgesi, A.; Levis, A.; Resegotti, A.; Ragona, R.; Anglesio, S.

    1988-01-01

    An original surgical method for gonadal protection in young women given pelvic radiation for Hodgkin's disease is presented. Lateral high ovarian transposition (LHAO) consists of the transposition of the ovaries into the paracolic gutter during staging laparotomy, after disconnecting the gonads from the fallopian tubes by dividing the tubo-ovarian vessels. The technique's effectiveness was assessed by a study using clinical investigation, radioimmunoassay (RIA) determination of sex hormones, and dosimetry; of 18 patients treated, 10 participated in the study. All but one have normal menses and hormone values, and one pregnancy occurred. We also calculated the doses absorbed by the ovaries and proved that, during inverted Y irradiation following LHAO, the ovaries are exposed to nearly one-half the dose they receive after traditional medial transposition. During subtotal nodal irradiation after LHAO, the irradiation dose is higher than after medialisation, but absolute values are minimal and castration is not induced

  18. Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial.

    Science.gov (United States)

    Ibrahim, Ahmed; Alfa, Attahiru

    2017-08-01

    This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes.

  19. Radiographic failure and rates of re-operation after acromioclavicular joint reconstruction: a comparison of surgical techniques.

    Science.gov (United States)

    Spencer, H T; Hsu, L; Sodl, J; Arianjam, A; Yian, E H

    2016-04-01

    To compare radiographic failure and re-operation rates of anatomical coracoclavicular (CC) ligament reconstructional techniques with non-anatomical techniques after chronic high grade acromioclavicular (AC) joint injuries. We reviewed chronic AC joint reconstructions within a region-wide healthcare system to identify surgical technique, complications, radiographic failure and re-operations. Procedures fell into four categories: (1) modified Weaver-Dunn, (2) allograft fixed through coracoid and clavicular tunnels, (3) allograft loop coracoclavicular fixation, and (4) combined allograft loop and synthetic cortical button fixation. Among 167 patients (mean age 38.1 years, (standard deviation (sd) 14.7) treated at least a four week interval after injury, 154 had post-operative radiographs available for analysis. Radiographic failure occurred in 33/154 cases (21.4%), with the lowest rate in Technique 4 (2/42 4.8%, p = 0.001). Half the failures occurred by six weeks, and the Kaplan-Meier survivorship at 24 months was 94.4% (95% confidence interval (CI) 79.6 to 98.6) for Technique 4 and 69.9% (95% CI 59.4 to 78.3) for the other techniques when combined. In multivariable survival analysis, Technique 4 had better survival than other techniques (Hazard Ratio 0.162, 95% CI 0.039 to 0.068, p = 0.013). Among 155 patients with a minimum of six months post-operative insurance coverage, re-operation occurred in 9.7% (15 patients). However, in multivariable logistic regression, Technique 4 did not reach a statistically significant lower risk for re-operation (odds ratio 0.254, 95% CI 0.05 to 1.3, p = 0.11). In this retrospective series, anatomical CC ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure. Anatomical coracoclavicular ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure. ©2016 The British Editorial

  20. New Techniques for Optimal Treatment Planning for LINAC-based Sterotactic Radiosurgery

    International Nuclear Information System (INIS)

    Suh, Tae Suk

    1992-01-01

    Since LINAC-based stereotactic radiosurgery uses multiple noncoplanar arcs, three-dimensional dose evaluation and many beam parameters, a lengthy computation time is required to optimize even the simplest case by a trial and error. The basic approach presented in this paper is to show promising methods using an experimental optimization and an analytic optimization. The purpose of this paper is not to describe the detailed methods, but introduce briefly, proceeding research done currently or in near future. A more detailed description will be shown in ongoing published papers. Experimental optimization is based on two approaches. One is shaping the target volumes through the use of multiple isocenters determined from dose experience and testing. The other method is conformal therapy using a beam eye view technique and field shaping. The analytic approach is to adapt computer-aided design optimization in finding optimum irradiation parameters automatically

  1. Connection between optimal control theory and adiabatic-passage techniques in quantum systems

    Science.gov (United States)

    Assémat, E.; Sugny, D.

    2012-08-01

    This work explores the relationship between optimal control theory and adiabatic passage techniques in quantum systems. The study is based on a geometric analysis of the Hamiltonian dynamics constructed from Pontryagin's maximum principle. In a three-level quantum system, we show that the stimulated Raman adiabatic passage technique can be associated to a peculiar Hamiltonian singularity. One deduces that the adiabatic pulse is solution of the optimal control problem only for a specific cost functional. This analysis is extended to the case of a four-level quantum system.

  2. Scalable Clustering of High-Dimensional Data Technique Using SPCM with Ant Colony Optimization Intelligence

    Directory of Open Access Journals (Sweden)

    Thenmozhi Srinivasan

    2015-01-01

    Full Text Available Clusters of high-dimensional data techniques are emerging, according to data noisy and poor quality challenges. This paper has been developed to cluster data using high-dimensional similarity based PCM (SPCM, with ant colony optimization intelligence which is effective in clustering nonspatial data without getting knowledge about cluster number from the user. The PCM becomes similarity based by using mountain method with it. Though this is efficient clustering, it is checked for optimization using ant colony algorithm with swarm intelligence. Thus the scalable clustering technique is obtained and the evaluation results are checked with synthetic datasets.

  3. The use of singular value gradients and optimization techniques to design robust controllers for multiloop systems

    Science.gov (United States)

    Newsom, J. R.; Mukhopadhyay, V.

    1983-01-01

    A method for designing robust feedback controllers for multiloop systems is presented. Robustness is characterized in terms of the minimum singular value of the system return difference matrix at the plant input. Analytical gradients of the singular values with respect to design variables in the controller are derived. A cumulative measure of the singular values and their gradients with respect to the design variables is used with a numerical optimization technique to increase the system's robustness. Both unconstrained and constrained optimization techniques are evaluated. Numerical results are presented for a two output drone flight control system.

  4. Surgical management of first branchial cleft anomaly presenting as infected retroauricular mass using a microscopic dissection technique.

    Science.gov (United States)

    Chan, Kai-Chieh; Chao, Wei-Chieh; Wu, Che-Ming

    2012-01-01

    This is a detailed description of the clinical and anatomical presentation of the first branchial cleft anomaly presenting as retroauricular infected mass. Our experience with a microscopic dissection with control of the sinus lumen from within the cyst is also described. Between 2001 and 2008, patients with the final histologic diagnosis of first branchial cleft anomaly in the retroauricular area were managed with a microscopic dissection technique with control of the sinus lumen from within the cyst. Classifications were done in accordance with Work, Olsen, and Chilla. Outcomes measured intervention as a function of disease recurrence and complications including facial nerve function was used. Eight patients with a mean age of 14.2 years were enrolled, and this included 4 females and 4 males. Four type 1 and 4 type 2 lesions as per the Work's and Chilla's classification were found, and there were 5 sinuses, 2 fistulae, and 1 cyst according to Olsen's classification. All patients presented to the department with acute infection at the time of diagnosis. Five of the 8 patients had previous surgical treatment, 2 of those had up to 3 previous operations. None of the patients were complicated by disease recurrence or had surgical related complications (facial nerve paresis or paralysis, infection, canal stenosis) requiring reoperation with more than 1 year of follow-up. First branchial cleft anomaly presenting as retroauricular infected mass can be effectively treated by adopting a microscopic dissection technique with control of the sinus lumen from within the cyst. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. A Randomized Controlled Trial of Video Education versus Skill Demonstration: Which Is More Effective in Teaching Sterile Surgical Technique?

    Science.gov (United States)

    Pilieci, Stephanie N; Salim, Saad Y; Heffernan, Daithi S; Itani, Kamal M F; Khadaroo, Rachel G

    2018-04-01

    Video education has many advantages over traditional education including efficiency, convenience, and individualized learning. Learning sterile surgical technique (SST) is imperative for medical students, because proper technique helps prevent surgical site infections (SSIs). We hypothesize that video education is at least as effective as traditional skill demonstration in teaching first-year medical students SST. A video series was created to demonstrate SST ( https://www.youtube.com/playlist?list=PLcRU-gvOmxE2mwMWkowouBkxGXkLZ8Uis ). A randomized controlled trial was designed to assess which education method best teaches SST: video education or skill demonstration. First-year medical students (n = 129) were consented and randomly assigned into two groups: those who attended a skill demonstration (control group; n = 70) and those who watched the video series (experimental group; n = 59). The control group attended a pre-existing 90-minute nurse educator-led skill demonstration. Participants then completed a 30-item multiple choice quiz to test their knowledge. Each group then received the alternate education method and completed a 23-item follow-up survey to determine their preferred method. Seven 2- to 6-minute videos (30 minutes total) were created on surgical attire, scrubbing, gowning and gloving, and maintaining sterility. The experimental group (n = 51) scored higher on the quiz compared with the control group (n = 63) (88% ± 1% versus 72% ± 1%; p < 0.0001). Students preferred the videos when it came to convenience, accessibility, efficiency, and review, and preferred the skill demonstration when it came to knowledge retention, preparedness, and ease of completion. Video education is superior to traditional skill demonstration in providing medical students with knowledge of SST. Students identified strengths to each method of teaching. Video education can augment medical students' knowledge prior to their operating room

  6. Fixation of revision implants is improved by new surgical technique to crack the sclerotic endosteal rim.

    Science.gov (United States)

    Kold, S; Soballe, K; Mouzin, O; Chen, Xiangmei; Toft, M; Bechtold, J

    2002-01-01

    We used an experimental model producing a tissue response with a sclerotic endosteal neo-cortical rim associated with implant loosening in humans: a 6 mm PMMA cylinder pistoned 500 m concentrically in a 7.5 mm hole, with polyethylene particles. At a second operation at eight weeks, the standard revision procedure removed the fibrous membrane in one knee, and the crack revision procedure was used to crack the sclerotic endosteal rim in the contralateral knee. Once stability was achieved following the revision procedures, loaded Ti plasma sprayed implants were inserted into the revision cavities of 8 dogs for an additional 4 weeks. Revision implant fixation (ultimate shear strength and energy absorption) was significantly enhanced by cracking the sclerotic endosteal rim. In conclusion, we demonstrated a simple technique of cracking the sclerotic endosteal rim as an additional method for improving revision fixation. (Hip International 2002; 2: 77-9).

  7. Advances in surgical techniques in non-small cell lung cancer.

    Science.gov (United States)

    Kim, Anthony W; Detterbeck, Frank C

    2013-12-01

    Thoracic surgery is a dynamic field, and many scientific, technological, technical, and organizational changes are occurring. A prominent example is the use of less invasive approaches to major resection of non-small cell lung cancer (NSCLC), both thoracoscopic and robotic. Sophisticated technology corroborated by clinical data has led to these approaches becoming accepted additions to the armamentarium. Additionally, improvements in perioperative pain management have also contributed to dramatically changing the experience of patients who undergo modern thoracic surgery. Lung cancer is being detected more often at an early stage. At the same time, advances in techniques, patient care, clinical science, and multidisciplinary treatment support an increased role for aggressive resection in the face of larger locally advanced tumors or for those with limited metastatic disease. These advances, conducted in the setting of multidisciplinary decision making, have resulted in real and palpable advancements for patients with lung cancer. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  8. Transplantation of infant kidneys - the surgical technique en bloc and transplant position variation: A case report

    Directory of Open Access Journals (Sweden)

    Popović Vladan

    2015-01-01

    Full Text Available Introduction. Due to the ever-present lack of kidney transplant grafts, more and more organs obtained from the so-called “marginal donors” group are accepted, which can provide suboptimal effect of transplantation, depending on their characteristics and/or implantation techniques. Case report. We presented a case with successful variation of kidney position with modified approach of kidney transplantation from an infant to an adult female patient with normal postoperative recovery. Urethral anastomosis was performed without antireflux procedure and this has not led to the development of reflux disease at an early stage. Conclusion. The position of a pair of kidneys proved to be satisfactory despite the growth of the kidney to the expected size and relatively small pelvis. There were no problems with venous stasis and kidney function from the very beginning was good.

  9. Comparison of surgical techniques of 111 medial malleolar fractures classified by fracture geometry.

    Science.gov (United States)

    Ebraheim, Nabil A; Ludwig, Todd; Weston, John T; Carroll, Trevor; Liu, Jiayong

    2014-05-01

    Evaluation of operative techniques used for medial malleolar fractures by classifying fracture geometry has not been well documented. One hundred eleven patients with medial malleolar fractures (transverse n = 63, oblique n = 29, vertical n = 7, comminuted n = 12) were included in this study. Seventy-two patients had complicating comorbidities. All patients were treated with buttress plate, lag screw, tension band, or K-wire fixation. Treatment outcomes were evaluated on the basis of radiological outcome (union, malunion, delayed union, or nonunion), need for operative revision, presence of postoperative complications, and AOFAS Ankle-Hindfoot score. For transverse fractures, tension band fixation showed the highest rate of union (79%), highest average AOFAS score (86), lowest revision rate (5%), and lowest complication rate (16%). For oblique fractures, lag screws showed the highest rate of union (71%), highest average AOFAS score (80), lowest revision rate (19%), and lowest complication rate (33%) of the commonly used fixation techniques. For vertical fractures, buttress plating was used in every case but 1, achieving union (whether normal or delayed) in all cases with an average AOFAS score of 84, no revisions, and a 17% complication rate. Comminuted fractures had relatively poor outcomes regardless of fixation method. The results of this study suggest that both tension bands and lag screws result in similar rates of union for transverse fractures of the medial malleolus, but that tension band constructs are associated with less need for revision surgery and fewer complications. In addition, our data demonstrate that oblique fractures were most effectively treated with lag screws and that vertical fractures attained superior outcomes with buttress plating. Level III, retrospective comparative series.

  10. Advances in the Surgical Management of Articular Cartilage Defects: Autologous Chondrocyte Implantation Techniques in the Pipeline.

    Science.gov (United States)

    Stein, Spencer; Strauss, Eric; Bosco, Joseph

    2013-01-01

    The purpose of this review is to gain insight into the latest methods of articular cartilage implantation (ACI) and to detail where they are in the Food and Drug Administration approval and regulatory process. A PubMed search was performed using the phrase "Autologous Chondrocyte Implantation" alone and with the words second generation and third generation. Additionally, clinicaltrials.gov was searched for the names of the seven specific procedures and the parent company websites were referenced. Two-Stage Techniques: BioCart II uses a FGF2v1 culture and a fibrinogen, thrombin matrix, whereas Hyalograft-C uses a Hyaff 11 matrix. MACI uses a collagen I/III matrix. Cartipatch consists of an agarose-alginate hydrogel. Neocart uses a high-pressure bioreactor for culturing with a type I collagen matrix. ChondroCelect makes use of a gene expression analysis to predict chondrocyte proliferation and has demonstrated significant clinical improvement, but failed to show superiority to microfracture in a phase III trial. One Step Technique: CAIS is an ACI procedure where harvested cartilage is minced and implanted into a matrix for defect filling. As full thickness defects in articular cartilage continue to pose a challenge to treat, new methods of repair are being researched. Later generation ACI has been developed to address the prevalence of fibrocartilage with microfracture and the complications associated with the periosteal flap of first generation ACI such as periosteal hypertrophy. The procedures and products reviewed here represent advances in tissue engineering, scaffolds and autologous chondrocyte culturing that may hold promise in our quest to alter the natural history of symptomatic chondral disease.

  11. Tuning of PID controller using optimization techniques for a MIMO process

    Science.gov (United States)

    Thulasi dharan, S.; Kavyarasan, K.; Bagyaveereswaran, V.

    2017-11-01

    In this paper, two processes were considered one is Quadruple tank process and the other is CSTR (Continuous Stirred Tank Reactor) process. These are majorly used in many industrial applications for various domains, especially, CSTR in chemical plants.At first mathematical model of both the process is to be done followed by linearization of the system due to MIMO process and controllers are the major part to control the whole process to our desired point as per the applications so the tuning of the controller plays a major role among the whole process. For tuning of parameters we use two optimizations techniques like Particle Swarm Optimization, Genetic Algorithm. The above techniques are majorly used in different applications to obtain which gives the best among all, we use these techniques to obtain the best tuned values among many. Finally, we will compare the performance of the each process with both the techniques.

  12. A Novel Analytical Technique for Optimal Allocation of Capacitors in Radial Distribution Systems

    Directory of Open Access Journals (Sweden)

    Sarfaraz Nawaz

    2017-07-01

    Full Text Available In this paper, a novel analytical technique is proposed to determine the optimal size and location of shunt capacitor units in radial distribution systems. An objective function is formulated to reduce real power loss, to improve the voltage profile and to increase annual cost savings. A new constant, the Loss Sensitivity Constant (LSC, is proposed here. The value of LSC decides the location and size of candidate buses. The technique is demonstrated on an IEEE-33 bus system at different load levels and the 130-bus distribution system of Jamawa Ramgarh village, Jaipur city. The obtained results are compared with the latest optimization techniques to show the effectiveness and robustness of the proposed technique.

  13. Real-time Continuous Esophageal High-resolution Manometry (HRM) During Laparoscopic Heller Myotomy and Dor Fundoplication for the Treatment of Achalasia. A Promising Novelty in Regards of Perfecting Surgical Technique: Could It Guide Surgical Technique Toward Excellent Results?

    Science.gov (United States)

    Triantafyllou, Tania; Doulami, Georgia; Papailiou, Joanna; Mantides, Apostolos; Zografos, Georgios; Theodorou, Dimitrios

    2016-12-01

    High-resolution manometry (HRM) is the gold-standard diagnostic tool for achalasia of the esophagus. Laparoscopic Heller-Dor technique is the preferred surgical approach with success rate estimated 90%. The use of intraoperative HRM provides real-time estimation of intraluminal esophageal pressures and identifies the exact points of esophageal luminal pressure during laparoscopy. Ten patients with achalasia underwent surgery. All patients preoperatively completed 1 manometric study and Quality of Life questionnaires (EORTC QLQ-C30 version 3.0) with Eckardt scores. We collected intraoperative manometry data and repeated manometric studies, EORTC QLQ-C30, and Eckardt scores postoperatively. Median Eckardt score was decreased from 7.5 to 0.5, mean resting pressure decreased from 51.4 to 11.9 mm Hg, whereas mean residual pressure diminished from 45.9 to 9.5 mm Hg postoperatively. The simultaneous use of HRM during the Heller-Dor technique may lead to an individualized management of the disease.

  14. Better Drumming Through Calibration: Techniques for Pre-Performance Robotic Percussion Optimization

    OpenAIRE

    Murphy, Jim; Kapur, Ajay; Carnegie, Dale

    2012-01-01

    A problem with many contemporary musical robotic percussion systems lies in the fact that solenoids fail to respond lin-early to linear increases in input velocity. This nonlinearity forces performers to individually tailor their compositions to specific robotic drummers. To address this problem, we introduce a method of pre-performance calibration using metaheuristic search techniques. A variety of such techniques are introduced and evaluated and the results of the optimized solenoid-based p...

  15. Surgical complications in 2,840 cases of hemorrhoidectomy by Milligan-Morgan, Ferguson and combined techniques

    Directory of Open Access Journals (Sweden)

    Guilherme de Almeida Santos

    2012-09-01

    Full Text Available The analysis of 2,840 cases of hemorrhoidectomy by open techniques of Milligan-Morgan (2,189 cases, Ferguson (341 cases and mixed (310 cases in 11,043 patients with hemorrhoidal disease (HD allowed the following conclusions. The patients' acceptance of surgical indication for hemorrhoidectomy was 25.7%. Hemorrhoidectomy was more common among women (53.8% than men (46.2%, and more accepted by women (26.5% than men (24.8%. Hemorrhoidectomy was more common in patients of the fourth (27.7%, fifth (21.9% and third (21.0% decades of age. Most patients who agreed to undergo hemorrhoidectomy were those of the second (38.2%, eighth (35.9% and ninth (34.5% decades of age. The overall incidence of surgical complications was 3.0% (87 cases: anal stenosis (1.8%, bleeding (0.8%, worsening of anal hypotonia (0.2%, sepsis (0.1% and systemic complications (0.1%, with no difference among the techniques used. The incidence of surgical complications by Milligan-Morgan technique was 3.0% - stenosis (1.9%, bleeding (1.9%, worsening of anal hypotonia (0.2% and systemic complications (0.04%. The incidence of surgical complications by Ferguson's technique was 3.5% - stenosis (1.7%, bleeding (0.6%, worsening of anal hypotonia (0.6% and sepsis (0.6%. And the incidence of surgical complications by mixed techniques was 2.5% - stenosis (1.0%, bleeding (0.3%, worsening of anal hypotonia (0.3%, sepsis (0.3% and systemic complications (0.3%. The incidence of surgical complications according to gender was 3.0% among women and 3.2% among men, with higher incidence of stenosis in women (2.0% and hemorrhage in men (1.1%. Surgical complications were more observed in the eighth (5.1% and seventh (3.8% decades of age. The incidence of anal stenosis was 1.8%, being 64.0% without hypotonia and 66.0% without anal fissure (66.0%, with annular stenosis as the most common anatomical shape (70.0%. Anal stenosis was more common among women (2.0% presenting mean age of 38.2 years, with no

  16. Massive cuff tears treated with arthroscopically assisted latissimus dorsi transfer. Surgical technique

    Science.gov (United States)

    De Cupis, Vincenzo; De Cupis, Mauro

    2012-01-01

    Summary Latissimus dorsi transfer is our preferred treatment for active disabled patients with a posterosuperior massive cuff tear. We present an arthroscopically assisted technique which avoids an incision through the deltoid obtaining a better and faster clinical outcome. The patient is placed in lateral decubitus. After the arthroscopic evaluation of the lesion through a posterior and a posterolateral portal, with the limb in traction we perform the preparation of the greater tuberosity of the humerus. We place the arm in abduction and internal rotation and we proceed to the harvest of the latissimus dorsi and the tendon preparation by stitching the two sides using very resistant sutures. After restoring limb traction, under arthroscopic visualization, we pass a curved grasper through the posterolateral portal by going to the armpit in the space between the teres minor and the posterior deltoid. Once the grasper has exited the access at the level of the axilla we fix two drainage transparent tubes, each with a wire inside, and, withdrawing it back, we shuttle the two tubes in the subacromial space. After tensioning the suture wires from the anterior portals these are assembled in a knotless anchor of 5.5 mm that we place in the prepared site on the greater tuberosity of the humerus. A shoulder brace at 15° of abduction and neutral rotation protect the patient for the first month post-surgery but physical therapy can immediately start. PMID:23738290

  17. Results of a protocol of transfusion threshold and surgical technique on transfusion requirements in burn patients.

    Science.gov (United States)

    O'Mara, Michael S; Hayetian, Fernando; Slater, Harvey; Goldfarb, I William; Tolchin, Eric; Caushaj, Philip F

    2005-08-01

    Blood loss and high rates of transfusion in burn centers remains an area of ongoing concern. Blood use brings the risk of infection, adverse reaction, and immunosuppression. A protocol to reduce blood loss and blood use was implemented. Analysis included 3-year periods before and after institution of the protocol. All patients were transfused for a hemoglobin below 8.0 gm/dL. Operations per admission did not change during the two time periods (0.78 in each). Overall units transfused per operation decreased from 1.56+/-0.06 to 1.25+/-0.14 units after instituting the protocol (pburns of less than 20% surface area, declining from 386 to 46 units after protocol institution, from 0.37 to 0.04 units per admission, and from 0.79 to 0.08 units per operation in this group of smallest burns. There was no change noted in the larger burns. This study suggests that a defined protocol of hemostasis, technique, and transfusion trigger should be implemented in the process of burn excision and grafting. This will help especially those patients with the smallest burns, essentially eliminating transfusion need in that group.

  18. Reconstruction of the mandible and the maxilla: the evolution of surgical technique.

    Science.gov (United States)

    Genden, Eric M

    2010-01-01

    The upper and lower jaws play an essential role in mastication, articulation, and cosmetic form. The mandible provides support for tongue position and elevation of the larynx during swallowing, while the maxilla provides support for the nasal structures as well as an opposing structure to the mandible during mastication. The evolution of mandibular and maxillary reconstruction dates back to the early 19th century. Before the introduction of free tissue transfer, a variety of local flaps, regional flaps, and prosthetics were introduced, yet each was met with eventual failure. Since the introduction of free tissue transfer, mandibular and maxillary reconstruction has become as much of an art as it has a science. Whether the mandibular or the palatomaxillary defects are a result of trauma, congenital deformity, or tumor extirpation, the resultant effect often disrupts both form and function. With these considerations taken together, jaw reconstruction is a unique undertaking in which the artistic reconstruction of the facial skeleton is met with the science of reestablishing the mechanics of mastication. The site, size, and associated soft-tissue defects represent the 3 most important factors in determining the impact of a given defect on function and aesthetics. There is also an inherent difference between defects that are sustained in a controlled fashion, such as during cancer ablation, and those that result from trauma. The consideration of these complexities in jaw reconstruction is reflected in the wide variety of approaches and techniques that have evolved over the past century.

  19. Advantages, Disadvantages, Indications, Contraindications and Surgical Technique of Laryngeal Airway Mask.

    Science.gov (United States)

    Jannu, Anubhav; Shekar, Ashim; Balakrishna, Ramdas; Sudarshan, H; Veena, G C; Bhuvaneshwari, S

    2017-12-01

    The beauty of the laryngeal mask is that it forms an air tight seal enclosing the larynx rather than plugging the pharynx, and avoid airway obstruction in the oropharynx. The goal of its development was to create an intermediate form of airway management face mask and endotracheal tube. Indication for its use includes any procedure that would normally involve the use of a face mask. The laryngeal mask airway was designed as a new concept in airway management and has been gaining a firm position in anesthetic practice. Despite wide spread use the definitive role of the laryngeal mask airway is yet to be established. In some situations, such as after failed tracheal intubation or in oral surgery its use is controversial. There are several unresolved issues, for example the effect of the laryngeal mask on regurgitation and whether or not cricoids pressure prevents placement of mask. We review the techniques of insertion, details of misplacement, and complications associated with use of the laryngeal mask. We then attempt to clarify the role of laryngeal mask in air way management during anesthesia, discussing the advantages and disadvantages as well as indications and contraindications of its use in oral and maxillofacial surgery.

  20. Novel surgical technique for complete traumatic rupture of the pancreas: A case report

    Directory of Open Access Journals (Sweden)

    Jauch Karl-Walter

    2011-09-01

    Full Text Available Abstract Introduction Complete pancreatic rupture is a rare injury. The typical mechanism by which this occurs is overstretching of the pancreas across the vertebral column during blunt abdominal trauma. The management of this injury depends on the location and extent of the injury. Case presentation A 45-year-old Caucasian woman presented with blunt abdominal trauma after she fell onto the end of a handlebar during a bicycle accident. She arrived in the emergency room with stable vital signs and an isolated bruise just above the umbilicus. A computed tomography scan revealed a complete rupture of the pancreas, just ventral to her superior mesenteric vein, and an accompanying hematoma but no additional injuries. An emergency laparotomy was performed; the head of the pancreas was oversewn with interrupted sutures and this was followed by a two-layer pancreaticojejunostomy with the tail of the pancreas. The recovery after surgery was completely uneventful. Conclusions Isolated complete pancreatic rupture is a rare injury that can be managed with complete organ preservation. The combination of suturing the pancreatic head and two-layer pancreaticojejunostomy with the pancreatic tail is a feasible technique to manage this condition.

  1. Novel Techniques with the Aid of a Staged CBCT Guided Surgical Protocol

    Directory of Open Access Journals (Sweden)

    Evdokia Chasioti

    2015-01-01

    Full Text Available The case report will present some novel techniques for using a “staged” protocol utilizing strategic periodontally involved teeth as transitional abutments in combination with CBCT guided implant surgery. Staging the case prevented premature loading of the grafted sites during the healing phase. A CBCT following a tenting screw guided bone regeneration procedure ensured adequate bone to place an implant fixture. Proper assessment of the CBCT allowed the surgeon to do an osteotome internal sinus lift in an optimum location. The depth of the bone needed for the osteotome sinus floor elevation was planned. The staged appliance allowed these sinus-augmented sites to heal for an extended period of time compared to implants, which were uncovered and loaded at an earlier time frame. The staged protocol and CBCT analysis enabled the immediate implants to be placed in proper alignment to the adjacent fixture. After teeth were extracted, the osseointegrated implants were converted to abutments for the transitional appliance. Finally, the staged protocol allowed for soft tissue enhancement in the implant and pontic areas prior to final insertion of the prosthesis.

  2. Optimal Timing of Surgical Antimicrobial Prophylaxis with Cefuroxim: Challenging the WHO Guidelines with 121,000 Prospectively Followed Patients

    Science.gov (United States)

    Widmer, Andreas F; Troillet, Nicolas; Thurneysen, Maurus; Atkinson, Andrew; Dangel, Marc; Kuster, Stefan P; Marschall, Jonas

    2017-01-01

    Abstract Background Surgical antimicrobial prophylaxis (SAP) is standard of care in clean surgery involving implants and in clean-contaminated surgical procedures. Timing of application of the antibiotic remains a debate: WHO recently extended the time prior to incision from 60 to 120 minutes, while CDC considers the availabdata insufficient to provide evidence-based guideline for timing. In addition, studies to date included different types of antibiotics with different T ½. Therefore, we prospectively followed 250’000 patients to further define the optimal timing for SAP Methods The Swiss national center for infection prevention (www.swissnoso.ch) started surveillance for surgical site infection (SSI) in 2009. Currently, 172 institutions participate throughout Switzerland, with routine postdicharge surveillance (adherence >90%) and on-site quality audits by a physician or infection control practitioner. The data collection includes age, sex, type of surgery, timing of SAP in minutes prior to incision, BMI, ASA score, antimicrobial agent. Inclusion criteria for this study were: adult patients undergoing cardiac surgery, orthopedic or abdominal surgery, antimicrobial prophylaxis with cefuroxime only (+metronidazole for abdominal surgery) and pathogen identified in cases of SSI was cefuroxime-susceptible. Data were analyzed using a generalized additive model (GAM) to allow non-parametric fits with relaxed assumptions on the actual relationship between response and predictor Results Of the 258’481 patients in the national SSI surveillance database 121’645 fulfilled the inclusion criteria (38% of patients did not require SAP, 18% had surgery with contaminated or dirty wounds, 2.7% were <18 years and data on timing and class of antibiotic were missing in 5.7%). The lowest risk of SSI was observed with application of SAP 0–30min prior incision, even after adjustment for age, sex, ASA score, type of surgery, BMI, and T1/2. (Figure, CI95 in blue

  3. Minimally invasive surgical technique: Percutaneous external fixation combined with titanium elastic nails for selective treatment of tibial fractures.

    Science.gov (United States)

    Tu, Kai-Kai; Zhou, Xian-Ting; Tao, Zhou-Shan; Chen, Wei-Kai; Huang, Zheng-Liang; Sun, Tao; Zhou, Qiang; Yang, Lei

    2015-12-01

    Several techniques have been described to treat tibial fractures, which respectively remains defects. This article presents a novel intra- and extramedullary fixation technique: percutaneous external fixator combined with titanium elastic nails (EF-TENs system). The purpose of this study is to introduce this new minimally invasive surgical technique and selective treatment of tibial fractures, particularly in segmental fractures, diaphysis fractures accompanied with distal or proximal bone subfissure, or fractures with poor soft-tissue problems. Following ethical approval, thirty-two patients with tibial fractures were treated by the EF-TENs system between January 2010 and December 2012. The follow-up studies included clinical and radiographic examinations. All relevant outcomes were recorded during follow-up. All thirty-two patients were achieved follow-ups. According to the AO classification, 3 Type A, 9 Type B and 20 Type C fractures were included respectively. According to the Anderson-Gustilo classification, there were 5 Type Grade II, 3 Type Grade IIIA and 2 Type Grade IIIB. Among 32 patients, 8 of them were segmental fractures. 12 fractures accompanied with bone subfissure. Results showed no nonunion case, with an average time of 23.7 weeks (range, 14-32 weeks). Among them, there were 3/32 delayed union patients and 0/32 malunion case. 4/32 patients developed a pin track infection and no patient suffered deep infection. The external fixator was removed with a mean time of 16.7 weeks (range, 10-26 weeks). Moreover, only 1/32 patient suffered with the restricted ROM of ankle, none with the restricted ROM of knee. This preliminary study indicated that the EF-TENs system, as a novel intra- and extramedullary fixation technique, had substantial effects on selective treatment of tibial fractures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Applying industrial process improvement techniques to increase efficiency in a surgical practice.

    Science.gov (United States)

    Reznick, David; Niazov, Lora; Holizna, Eric; Siperstein, Allan

    2014-10-01

    The goal of this study was to examine how industrial process improvement techniques could help streamline the preoperative workup. Lean process improvement was used to streamline patient workup at an endocrine surgery service at a tertiary medical center utilizing multidisciplinary collaboration. The program consisted of several major changes in how patients are processed in the department. The goal was to shorten the wait time between initial call and consult visit and between consult and surgery. We enrolled 1,438 patients enrolled in the program. The wait time from the initial call until consult was reduced from 18.3 ± 0.7 to 15.4 ± 0.9 days. Wait time from consult until operation was reduced from 39.9 ± 1.5 to 33.9 ± 1.3 days for the overall practice and to 15.0 ± 4.8 days for low-risk patients. Patient cancellations were reduced from 27.9 ± 2.4% to 17.3 ± 2.5%. Overall patient flow increased from 30.9 ± 5.1 to 52.4 ± 5.8 consults per month (all P process improvement methodology, surgery patients can benefit from an improved, streamlined process with significant reduction in wait time from call to initial consult and initial consult to surgery, with reduced cancellations. This generalized process has resulted in increased practice throughput and efficiency and is applicable to any surgery practice. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Basal cell carcinoma of the outer nose: Overview on surgical techniques and analysis of 312 patients

    Directory of Open Access Journals (Sweden)

    Uwe Wollina

    2014-01-01

    Full Text Available Background: Basal cell carcinoma of the nose is common, with a potential of local recurrence and high-risk features. Materials and Methods: We provide a review on anatomy of the nose, tumour surgery and defect closure on the nose. We analysed our own patients with nasal BCC of a 24 months period. Results: We identified 321 patients with nasal BCC. There was a predominance of female patients of 1.2 to 1. The mean age was 74.8 years. Slow Mohs technique was employed for all tumours until 3D tumour-free margins were achieved. That resulted on average in 1.8 ± 0.7 Mohs stages. The most common histologic types were solitary (n = 182, morpheic (79, and micronodular (20, Perineural infiltration was evident in 56 tumours. Primary closure after mobilisation of soft tissue was possible in 105 BCCs. Advancement flaps were used in 91 tumours, rotation flaps in 47, transposition flaps in 34 tumours, and combined procedures in 6 cases. In 36 patients full-thickness skin grafting was performed. In two patients healing by second intention was preferred. Partial flap loss was seen in four patients (1.4%. All of them had significant underlying pathologies. None of the tumours treated showed a relapse during the observation time. However, this is a limitation of the present study since follow-up was on average only 10 months. Conclusions: BCCs of the nose are common. Only 3D-controlled micrographic surgery (Mohs or slow Mohs guarantee a high rate of complete tumour removal and a very low risk of recurrence.

  6. Solar photovoltaic power forecasting using optimized modified extreme learning machine technique

    Directory of Open Access Journals (Sweden)

    Manoja Kumar Behera

    2018-06-01

    Full Text Available Prediction of photovoltaic power is a significant research area using different forecasting techniques mitigating the effects of the uncertainty of the photovoltaic generation. Increasingly high penetration level of photovoltaic (PV generation arises in smart grid and microgrid concept. Solar source is irregular in nature as a result PV power is intermittent and is highly dependent on irradiance, temperature level and other atmospheric parameters. Large scale photovoltaic generation and penetration to the conventional power system introduces the significant challenges to microgrid a smart grid energy management. It is very critical to do exact forecasting of solar power/irradiance in order to secure the economic operation of the microgrid and smart grid. In this paper an extreme learning machine (ELM technique is used for PV power forecasting of a real time model whose location is given in the Table 1. Here the model is associated with the incremental conductance (IC maximum power point tracking (MPPT technique that is based on proportional integral (PI controller which is simulated in MATLAB/SIMULINK software. To train single layer feed-forward network (SLFN, ELM algorithm is implemented whose weights are updated by different particle swarm optimization (PSO techniques and their performance are compared with existing models like back propagation (BP forecasting model. Keywords: PV array, Extreme learning machine, Maximum power point tracking, Particle swarm optimization, Craziness particle swarm optimization, Accelerate particle swarm optimization, Single layer feed-forward network

  7. Experimental evaluation of optimal Vehicle Dynamic Control based on the State Dependent Riccati Equation technique

    NARCIS (Netherlands)

    Alirezaei, M.; Kanarachos, S.A.; Scheepers, B.T.M.; Maurice, J.P.

    2013-01-01

    Development and experimentally evaluation of an optimal Vehicle Dynamic Control (VDC) strategy based on the State Dependent Riccati Equation (SDRE) control technique is presented. The proposed nonlinear controller is based on a nonlinear vehicle model with nonlinear tire characteristics. A novel

  8. Space-mapping techniques applied to the optimization of a safety isolating transformer

    NARCIS (Netherlands)

    T.V. Tran; S. Brisset; D. Echeverria (David); D.J.P. Lahaye (Domenico); P. Brochet

    2007-01-01

    textabstractSpace-mapping optimization techniques allow to allign low-fidelity and high-fidelity models in order to reduce the computational time and increase the accuracy of the solution. The main idea is to build an approximate model from the difference of response between both models. Therefore

  9. Expert system and process optimization techniques for real-time monitoring and control of plasma processes

    Science.gov (United States)

    Cheng, Jie; Qian, Zhaogang; Irani, Keki B.; Etemad, Hossein; Elta, Michael E.

    1991-03-01

    To meet the ever-increasing demand of the rapidly-growing semiconductor manufacturing industry it is critical to have a comprehensive methodology integrating techniques for process optimization real-time monitoring and adaptive process control. To this end we have accomplished an integrated knowledge-based approach combining latest expert system technology machine learning method and traditional statistical process control (SPC) techniques. This knowledge-based approach is advantageous in that it makes it possible for the task of process optimization and adaptive control to be performed consistently and predictably. Furthermore this approach can be used to construct high-level and qualitative description of processes and thus make the process behavior easy to monitor predict and control. Two software packages RIST (Rule Induction and Statistical Testing) and KARSM (Knowledge Acquisition from Response Surface Methodology) have been developed and incorporated with two commercially available packages G2 (real-time expert system) and ULTRAMAX (a tool for sequential process optimization).

  10. Application of Genetic Algorithm and Particle Swarm Optimization techniques for improved image steganography systems

    Directory of Open Access Journals (Sweden)

    Jude Hemanth Duraisamy

    2016-01-01

    Full Text Available Image steganography is one of the ever growing computational approaches which has found its application in many fields. The frequency domain techniques are highly preferred for image steganography applications. However, there are significant drawbacks associated with these techniques. In transform based approaches, the secret data is embedded in random manner in the transform coefficients of the cover image. These transform coefficients may not be optimal in terms of the stego image quality and embedding capacity. In this work, the application of Genetic Algorithm (GA and Particle Swarm Optimization (PSO have been explored in the context of determining the optimal coefficients in these transforms. Frequency domain transforms such as Bandelet Transform (BT and Finite Ridgelet Transform (FRIT are used in combination with GA and PSO to improve the efficiency of the image steganography system.

  11. Optimization long hole blast fragmentation techniques and detonating circuit underground uranium mine stope

    International Nuclear Information System (INIS)

    Li Qin; Yang Lizhi; Song Lixia; Qin De'en; Xue Yongshe; Wang Zhipeng

    2012-01-01

    Aim at high rate of large blast fragmentation, a big difficulty in long hole drilling and blasting underground uranium mine stope, it is pointed out at the same time of taking integrated technical management measures, the key is to optimize the drilling and blasting parameters and insure safety the act of one that primes, adopt 'minimum burden' blasting technique, renew the stope fragmentation process, and use new process of hole bottom indirect initiation fragmentation; optimize the detonating circuit and use safe, reliable and economically rational duplex non-electric detonating circuit. The production practice shows that under the guarantee of strictly controlled construction quality, the application of optimized blast fragmentation technique has enhanced the reliability of safety detonation and preferably solved the problem of high rate of large blast fragments. (authors)

  12. Vertical-to-Horizontal Rotational Myocutaneous Flap for Repairing Cicatricial Lower Lid Ectropion: A Novel Surgical Technique

    Directory of Open Access Journals (Sweden)

    Yu-Fan Chang

    2017-01-01

    Full Text Available Objective. To evaluate the efficacy and complications of a novel surgical technique for cicatricial lower lid ectropion that uses a vertical-to-horizontal (V-to-H rotational myocutaneous flap procedure (Tsai procedure. Methods. We performed the V-to-H rotational myocutaneous flap procedure on 20 eyelids in 20 patients with mild to moderate cicatricial lower lid ectropion. A vertical myocutaneous flap was created from the anterior lamella of the vertical pedicle in the lateral third of the lower eyelid. Following a horizontal relaxing incision from the base of the flap, a vertical myocutaneous flap was created and rotated to horizontal. Two patients with combined cicatricial ectropion and paralytic lagophthalmos simultaneously underwent additional lateral tarsorrhaphy. Results. After a minimum follow-up period of 6 months, all patients showed good anatomical and functional improvement with decreased dependence on topical lubricants and a satisfactory cosmetic appearance. Two patients with combined cicatricial and paralytic ectropion had mild residual asymptomatic lagophthalmos. No patients required further revision surgery and there were no complications or recurrence. Conclusion. The V-to-H rotational myocutaneous flap technique was an effective and simple one-stage procedure for correcting cicatricial lower lid ectropion. It lengthened the anterior lamella and tightened horizontal eyelid laxity without the need for a free skin graft.

  13. Surgical timing after chemoradiotherapy for rectal cancer, analysis of technique (STARRCAT): results of a feasibility multi-centre randomized controlled trial.

    Science.gov (United States)

    Foster, J D; Ewings, P; Falk, S; Cooper, E J; Roach, H; West, N P; Williams-Yesson, B A; Hanna, G B; Francis, N K

    2016-10-01

    The optimal time of rectal resection after long-course chemoradiotherapy (CRT) remains unclear. A feasibility study was undertaken for a multi-centre randomized controlled trial evaluating the impact of the interval after chemoradiotherapy on the technical complexity of surgery. Patients with rectal cancer were randomized to either a 6- or 12-week interval between CRT and surgery between June 2012 and May 2014 (ISRCTN registration number: 88843062). For blinded technical complexity assessment, the Observational Clinical Human Reliability Analysis technique was used to quantify technical errors enacted within video recordings of operations. Other measured outcomes included resection completeness, specimen quality, radiological down-staging, tumour cell density down-staging and surgeon-reported technical complexity. Thirty-one patients were enrolled: 15 were randomized to 6 and 16-12 weeks across 7 centres. Fewer eligible patients were identified than had been predicted. Of 23 patients who underwent resection, mean 12.3 errors were observed per case at 6 weeks vs. 10.7 at 12 weeks (p = 0.401). Other measured outcomes were similar between groups. The feasibility of measurement of operative performance of rectal cancer surgery as an endpoint was confirmed in this exploratory study. Recruitment of sufficient numbers of patients represented a challenge, and a proportion of patients did not proceed to resection surgery. These results suggest that interval after CRT may not substantially impact upon surgical technical performance.

  14. Design refinement of multilayer optical thin film devices with two optimization techniques

    International Nuclear Information System (INIS)

    Apparao, K.V.S.R.

    1992-01-01

    The design efficiency of two different optimization techniques of designing multilayer optical thin film devices is compared. Ten different devices of varying complexities are chosen as design examples for the comparison. The design refinement efficiency and the design parameter characteristics of all the sample designs obtained with the two techniques are compared. The results of the comparison demonstrate that the new method of design developed using damped least squares technique with indirect derivatives give superior and efficient designs compared to the method developed with direct derivatives. (author). 23 refs., 4 tabs., 14 figs

  15. A Standalone PV System with a Hybrid P&O MPPT Optimization Technique

    Directory of Open Access Journals (Sweden)

    S. Hota

    2017-12-01

    Full Text Available In this paper a maximum power point tracking (MPPT design for a photovoltaic (PV system using a hybrid optimization technique is proposed. For maximum power transfer, maximum harvestable power from a PV cell in a dynamically changing surrounding should be known. The proposed technique is compared with the conventional Perturb and Observe (P&O technique. A comparative analysis of power-voltage and current-voltage characteristics of a PV cell with and without the MPPT module when connected to the grid was performed in SIMULINK, to demonstrate the increment in the efficiency of the PV module after using the MPPT module.

  16. Optimization Techniques for Improving the Performance of Silicone-Based Dielectric Elastomers

    DEFF Research Database (Denmark)

    Skov, Anne Ladegaard; Yu, Liyun

    2017-01-01

    the electro-mechanical performance of dielectric elastomers are highlighted. Various optimization methods for improved energy transduction are investigated and discussed, with special emphasis placed on the promise each method holds. The compositing and blending of elastomers are shown to be simple, versatile...... methods that can solve a number of optimization issues. More complicated methods, involving chemical modification of the silicone backbone as well as controlling the network structure for improved mechanical properties, are shown to solve yet more issues. From the analysis, it is obvious...... that there is not a single optimization technique that will lead to the universal optimization of dielectric elastomer films, though each method may lead to elastomers with certain features, and thus certain potentials....

  17. Radiation dose optimization research: Exposure technique approaches in CR imaging – A literature review

    International Nuclear Information System (INIS)

    Seeram, Euclid; Davidson, Rob; Bushong, Stewart; Swan, Hans

    2013-01-01

    The purpose of this paper is to review the literature on exposure technique approaches in Computed Radiography (CR) imaging as a means of radiation dose optimization in CR imaging. Specifically the review assessed three approaches: optimization of kVp; optimization of mAs; and optimization of the Exposure Indicator (EI) in practice. Only papers dating back to 2005 were described in this review. The major themes, patterns, and common findings from the literature reviewed showed that important features are related to radiation dose management strategies for digital radiography include identification of the EI as a dose control mechanism and as a “surrogate for dose management”. In addition the use of the EI has been viewed as an opportunity for dose optimization. Furthermore optimization research has focussed mainly on optimizing the kVp in CR imaging as a means of implementing the ALARA philosophy, and studies have concentrated on mainly chest imaging using different CR systems such as those commercially available from Fuji, Agfa, Kodak, and Konica-Minolta. These studies have produced “conflicting results”. In addition, a common pattern was the use of automatic exposure control (AEC) and the measurement of constant effective dose, and the use of a dose-area product (DAP) meter

  18. A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy

    Science.gov (United States)

    Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

    2018-01-01

    With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

  19. A singular value decomposition linear programming (SVDLP) optimization technique for circular cone based robotic radiotherapy.

    Science.gov (United States)

    Liang, Bin; Li, Yongbao; Wei, Ran; Guo, Bin; Xu, Xuang; Liu, Bo; Li, Jiafeng; Wu, Qiuwen; Zhou, Fugen

    2018-01-05

    With robot-controlled linac positioning, robotic radiotherapy systems such as CyberKnife significantly increase freedom of radiation beam placement, but also impose more challenges on treatment plan optimization. The resampling mechanism in the vendor-supplied treatment planning system (MultiPlan) cannot fully explore the increased beam direction search space. Besides, a sparse treatment plan (using fewer beams) is desired to improve treatment efficiency. This study proposes a singular value decomposition linear programming (SVDLP) optimization technique for circular collimator based robotic radiotherapy. The SVDLP approach initializes the input beams by simulating the process of covering the entire target volume with equivalent beam tapers. The requirements on dosimetry distribution are modeled as hard and soft constraints, and the sparsity of the treatment plan is achieved by compressive sensing. The proposed linear programming (LP) model optimizes beam weights by minimizing the deviation of soft constraints subject to hard constraints, with a constraint on the l 1 norm of the beam weight. A singular value decomposition (SVD) based acceleration technique was developed for the LP model. Based on the degeneracy of the influence matrix, the model is first compressed into lower dimension for optimization, and then back-projected to reconstruct the beam weight. After beam weight optimization, the number of beams is reduced by removing the beams with low weight, and optimizing the weights of the remaining beams using the same model. This beam reduction technique is further validated by a mixed integer programming (MIP) model. The SVDLP approach was tested on a lung case. The results demonstrate that the SVD acceleration technique speeds up the optimization by a factor of 4.8. Furthermore, the beam reduction achieves a similar plan quality to the globally optimal plan obtained by the MIP model, but is one to two orders of magnitude faster. Furthermore, the SVDLP

  20. Clinical results of a surgical technique using endobuttons for complete tendon tear of pectoralis major muscle: report of five cases

    Directory of Open Access Journals (Sweden)

    Uchiyama Yoshiyasu

    2011-09-01

    Full Text Available Abstract Background We herein describe a surgical technique for the repair of complete tear of the pectoralis major (PM tendon using endobuttons to strengthen initial fixation. Methods Five male patients (3 judo players, 1 martial arts player, and 1 body builder were treated within 2 weeks of sustaining complete tear of the PM tendon. Average age at surgery and follow-up period were 28.4 years (range, 23-33 and 28.8 months (range, 24-36. A rectangular bone trough (about 1 × 4 cm was created on the humerus at the insertion of the distal PM tendon. The tendon stump was introduced into this trough, and fixed to the reverse side of the humeral cortex using endobuttons and non-absorbable suture. Clinical assessment of re-tear was examined by MRI. Shoulder range of motion (ROM, outcome of treatment, and isometric power were measured at final follow-up. Results There were no clinical re-tears, and MRI findings also showed continuity of the PM tendon in all cases at final follow-up. Average ROM did not differ significantly between the affected and unaffected shoulders. The clinical outcomes at final follow-up were excellent (4/5 cases or good (1/5. In addition, postoperative isometric power in horizontal flexion of the affected shoulder showed complete recovery when compared with the unaffected side. Conclusions Satisfactory outcomes could be obtained when surgery using the endobutton technique was performed within 2 weeks after complete tear of the PM tendon. Therefore, our new technique appears promising as a useful method to treat complete tear of the PM tendon.

  1. Optimization and validation of an existing, surgical and robust dry eye rat model for the evaluation of therapeutic compounds.

    Science.gov (United States)

    Joossen, Cedric; Lanckacker, Ellen; Zakaria, Nadia; Koppen, Carina; Joossens, Jurgen; Cools, Nathalie; De Meester, Ingrid; Lambeir, Anne-Marie; Delputte, Peter; Maes, Louis; Cos, Paul

    2016-05-01

    The aim of this research was to optimize and validate an animal model for dry eye, adopting clinically relevant evaluation parameters. Dry eye was induced in female Wistar rats by surgical removal of the exorbital lacrimal gland. The clinical manifestations of dry eye were evaluated by tear volume measurements, corneal fluorescein staining, cytokine measurements in tear fluid, MMP-9 mRNA expression and CD3(+) cell infiltration in the conjunctiva. The animal model was validated by treatment with Restasis(®) (4 weeks) and commercial dexamethasone eye drops (2 weeks). Removal of the exorbital lacrimal gland resulted in 50% decrease in tear volume and a gradual increase in corneal fluorescein staining. Elevated levels of TNF-α and IL-1α have been registered in tear fluid together with an increase in CD3(+) cells in the palpebral conjunctiva when compared to control animals. Additionally, an increase in MMP-9 mRNA expression was recorded in conjunctival tissue. Reference treatment with Restasis(®) and dexamethasone eye drops had a positive effect on all evaluation parameters, except on tear volume. This rat dry eye model was validated extensively and judged appropriate for the evaluation of novel compounds and therapeutic preparations for dry eye disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Prospective Study of the Surgical Techniques Used in Primary Rhinoplasty on the Caucasian Nose and Comparison of the Preoperative and Postoperative Anthropometric Nose Measurements

    Science.gov (United States)

    Berger, Cezar Augusto Sarraf; Freitas, Renato da Silva; Malafaia, Osvaldo; Pinto, José Simão de Paula; Macedo Filho, Evaldo Dacheux; Mocellin, Marcos; Fagundes, Marina Serrato Coelho

    2014-01-01

    Introduction The knowledge and study of surgical techniques and anthropometric measurements of the nose make possible a qualitative and quantitative analysis of surgical results. Objective Study the main technique used in rhinoplasty on Caucasian noses and compare preoperative and postoperative anthropometric measurements of the nose. Methods A prospective study with 170 patients was performed at a private hospital. Data were collected using the Electronic System Integrated of Protocols software (Sistema Integrado de Protocolos Eletrônicos, SINPE©). The surgical techniques used in the nasal dorsum and tip were evaluated. Preoperative and 12-month follow-up photos as well as the measurements compared with the ideal aesthetic standard of a Caucasian nose were analyzed objectively. Student t test and standard deviation test were applied. Results There was a predominance of endonasal access (94.4%). The most common dorsum technique was hump removal (33.33%), and the predominance of sutures (24.76%) was observed on the nasal tip, with the lateral intercrural the most frequent (32.39%). Comparison between preoperative and postoperative photos found statistically significant alterations on the anthropometric measurements of the noses. Conclusion The main surgical techniques on Caucasian noses were evaluated, and a great variety was found. The evaluation of anthropometric measurements of the nose proved the efficiency of the performed procedures. PMID:25992149

  3. Prospective Study of the Surgical Techniques Used in Primary Rhinoplasty on the Caucasian Nose and Comparison of the Preoperative and Postoperative Anthropometric Nose Measurements

    Directory of Open Access Journals (Sweden)

    Berger, Cezar Augusto Sarraf

    2014-12-01

    Full Text Available Introduction The knowledge and study of surgical techniques and anthropometric measurements of the nose make possible a qualitative and quantitative analysis of surgical results. Objective Study the main technique used in rhinoplasty on Caucasian noses and compare preoperative and postoperative anthropometric measurements of the nose. Methods A prospective study with 170 patients was performed at a private hospital. Data were collected using the Electronic System Integrated of Protocols software (Sistema Integrado de Protocolos Eletrônicos, SINPE©. The surgical techniques used in the nasal dorsum and tip were evaluated. Preoperative and 12-month follow-up photos as well as the measurements compared with the ideal aesthetic standard of a Caucasian nose were analyzed objectively. Student t test and standard deviation test were applied. Results There was a predominance of endonasal access (94.4%. The most common dorsum technique was hump removal (33.33%, and the predominance of sutures (24.76% was observed on the nasal tip, with the lateral intercrural the most frequent (32.39%. Comparison between preoperative and postoperative photos found statistically significant alterations on the anthropometric measurements of the noses. Conclusion The main surgical techniques on Caucasian noses were evaluated, and a great variety was found. The evaluation of anthropometric measurements of the nose proved the efficiency of the performed procedures.

  4. Surgical orthodontics.

    Science.gov (United States)

    Strohl, Alexis M; Vitkus, Lauren

    2017-08-01

    The article reviews some commonly used orthodontic treatments as well as new strategies to assist in the correction of malocclusion. Many techniques are used in conjunction with surgical intervention and are a necessary compliment to orthognathic surgery. Basic knowledge of these practices will aid in the surgeon's ability to adequately treat the patient. Many orthodontists and surgeons are eliminating presurgical orthodontics to adopt a strategy of 'surgery first' orthodontics in orthognathic surgery. This has the benefit of immediate improvement in facial aesthetics and shorter treatment times. The advent of virtual surgical planning has helped facilitate the development of this new paradigm by making surgical planning faster and easier. Furthermore, using intraoperative surgical navigation is improving overall precision and outcomes. A variety of surgical and nonsurgical treatments may be employed in the treatment of malocclusion. It is important to be familiar with all options available and tailor the patient's treatment plan accordingly. Surgery-first orthodontics, intraoperative surgical navigation, virtual surgical planning, and 3D printing are evolving new techniques that are producing shorter treatment times and subsequently improving patient satisfaction without sacrificing long-term stability.

  5. Surgical stabilization of rib fractures using Inion OTPS wraps--techniques and quality of life follow-up.

    Science.gov (United States)

    Campbell, Nicole; Conaglen, Paul; Martin, Katherine; Antippa, Phillip

    2009-09-01

    A variety of operative techniques have been described in the past for the surgical stabilization of fractured ribs. From February 2004 to November 2008, consecutive patients who underwent open reduction and internal fixation of traumatic fractured ribs during their index admission using the Inion orthopedic trauma plating system (OTPS) at a Level I trauma center were retrospectively analyzed. Demographics, Injury Severity Scores, number and site of rib fractures, operative details, and complications were recorded. All patients were followed-up with a questionnaire assessing chest symptoms, disability, and quality of life. Thirty-two patients underwent surgical stabilization with Inion OTPS. Road crashes were the commonest mechanism of injury (81%), followed by falls. Seventy-two percent of patients were male, with a median age at operation of 53 years (interquartile range [IQR], 40-64 years). Median number of ribs fixed was 3 (IQR, 2-4), while median number of fractures was 9 (IQR, 6-13). Median time to fixation was 5 days (IQR, 3-7 days), intensive care unit stay 3 days (IQR, 0.8-6.3 days), and total hospital stay 13.5 days (IQR, 8.8-22 days). Wound infection occurred in 19%, with nonunion of a fixed fracture in one patient. Sixty-three percent of patients completed the survey with a mean time between open reduction and internal fixation and questionnaire of 1,039 days (+/-480 days). Patients reported low levels of pain at rest and with coughing (median at rest 1.0/10 [IQR, 0-2.3/10]; with coughing 1.3/10 [IQR, 0-3.75/10]). Chest wall stiffness was experienced by 60% of patients, while dyspnoea at rest was reported by 20% of patients. Mean return to work (for 55%) was 3.9 months (+/-3.3 months). All patients were satisfied with the results of their operation. Patients demonstrated low levels of pain and satisfactory rehabilitation. The Inion OTPS system has several advantages including gradual transference of stress loads to bone, micromotion across the fracture

  6. Rotor Pole Shape Optimization of Permanent Magnet Brushless DC Motors Using the Reduced Basis Technique

    Directory of Open Access Journals (Sweden)

    GHOLAMIAN, A. S.

    2009-06-01

    Full Text Available In this paper, a magnet shape optimization method for reduction of cogging torque and torque ripple in Permanent Magnet (PM brushless DC motors is presented by using the reduced basis technique coupled by finite element and design of experiments methods. The primary objective of the method is to reduce the enormous number of design variables required to define the magnet shape. The reduced basis technique is a weighted combination of several basis shapes. The aim of the method is to find the best combination using the weights for each shape as the design variables. A multi-level design process is developed to find suitable basis shapes or trial shapes at each level that can be used in the reduced basis technique. Each level is treated as a separated optimization problem until the required objective is achieved. The experimental design of Taguchi method is used to build the approximation model and to perform optimization. This method is demonstrated on the magnet shape optimization of a 6-poles/18-slots PM BLDC motor.

  7. A characteristic study of CCF modeling techniques and optimization of CCF defense strategies

    International Nuclear Information System (INIS)

    Kim, Min Chull

    2000-02-01

    Common Cause Failures (CCFs ) are among the major contributors to risk and core damage frequency (CDF ) from operating nuclear power plants (NPPs ). Our study on CCF focused on the following aspects : 1) a characteristic study on the CCF modeling techniques and 2) development of the optimal CCF defense strategy. Firstly, the characteristics of CCF modeling techniques were studied through sensitivity study of CCF occurrence probability upon system redundancy. The modeling techniques considered in this study include those most widely used worldwide, i.e., beta factor, MGL, alpha factor, and binomial failure rate models. We found that MGL and alpha factor models are essentially identical in terms of the CCF probability. Secondly, in the study for CCF defense, the various methods identified in the previous studies for defending against CCF were classified into five different categories. Based on these categories, we developed a generic method by which the optimal CCF defense strategy can be selected. The method is not only qualitative but also quantitative in nature: the selection of the optimal strategy among candidates is based on the use of analytic hierarchical process (AHP). We applied this method to two motor-driven valves for containment sump isolation in Ulchin 3 and 4 nuclear power plants. The result indicates that the method for developing an optimal CCF defense strategy is effective

  8. Loading pattern optimization by multi-objective simulated annealing with screening technique

    International Nuclear Information System (INIS)

    Tong, K. P.; Hyun, C. L.; Hyung, K. J.; Chang, H. K.

    2006-01-01

    This paper presents a new multi-objective function which is made up of the main objective term as well as penalty terms related to the constraints. All the terms are represented in the same functional form and the coefficient of each term is normalized so that each term has equal weighting in the subsequent simulated annealing optimization calculations. The screening technique introduced in the previous work is also adopted in order to save computer time in 3-D neutronics evaluation of trial loading patterns. For numerical test of the new multi-objective function in the loading pattern optimization, the optimum loading patterns for the initial and the cycle 7 reload PWR core of Yonggwang Unit 4 are calculated by the simulated annealing algorithm with screening technique. A total of 10 optimum loading patterns are obtained for the initial core through 10 independent simulated annealing optimization runs. For the cycle 7 reload core one optimum loading pattern has been obtained from a single simulated annealing optimization run. More SA optimization runs will be conducted to optimum loading patterns for the cycle 7 reload core and results will be presented in the further work. (authors)

  9. A study of optimization techniques in HDR brachytherapy for the prostate

    Science.gov (United States)

    Pokharel, Ghana Shyam

    . Based on our study, DVH based objective function performed better than traditional variance based objective function in creating a clinically acceptable plan when executed under identical conditions. Thirdly, we studied the multiobjective optimization strategy using both DVH and variance based objective functions. The optimization strategy was to create several Pareto optimal solutions by scanning the clinically relevant part of the Pareto front. This strategy was adopted to decouple optimization from decision such that user could select final solution from the pool of alternative solutions based on his/her clinical goals. The overall quality of treatment plan improved using this approach compared to traditional class solution approach. In fact, the final optimized plan selected using decision engine with DVH based objective was comparable to typical clinical plan created by an experienced physicist. Next, we studied the hybrid technique comprising both stochastic and deterministic algorithm to optimize both dwell positions and dwell times. The simulated annealing algorithm was used to find optimal catheter distribution and the DVH based algorithm was used to optimize 3D dose distribution for given catheter distribution. This unique treatment planning and optimization tool was capable of producing clinically acceptable highly reproducible treatment plans in clinically reasonable time. As this algorithm was able to create clinically acceptable plans within clinically reasonable time automatically, it is really appealing for real time procedures. Next, we studied the feasibility of multiobjective optimization using evolutionary algorithm for real time HDR brachytherapy for the prostate. The algorithm with properly tuned algorithm specific parameters was able to create clinically acceptable plans within clinically reasonable time. However, the algorithm was let to run just for limited number of generations not considered optimal, in general, for such algorithms. This was

  10. Radioactive tracer technique in process optimization: applications in the chemical industry

    International Nuclear Information System (INIS)

    Charlton, J.S.

    1989-01-01

    Process optimization is concerned with the selection of the most appropriate technological design of the process and with controlling its operation to obtain maximum benefit. The role of radioactive tracers in process optimization is discussed and the various circumstances under which such techniques may be beneficially applied are identified. Case studies are presented which illustrate how radioisotopes may be used to monitor plant performance under dynamic conditions to improve production efficiency and to investigate the cause of production limitations. In addition, the use of sealed sources to provide information complementary to the tracer study is described. (author)

  11. Analysis on the Metrics used in Optimizing Electronic Business based on Learning Techniques

    Directory of Open Access Journals (Sweden)

    Irina-Steliana STAN

    2014-09-01

    Full Text Available The present paper proposes a methodology of analyzing the metrics related to electronic business. The drafts of the optimizing models include KPIs that can highlight the business specific, if only they are integrated by using learning-based techniques. Having set the most important and high-impact elements of the business, the models should get in the end the link between them, by automating business flows. The human resource will be found in the situation of collaborating more and more with the optimizing models which will translate into high quality decisions followed by profitability increase.

  12. Linear triangular optimization technique and pricing scheme in residential energy management systems

    Science.gov (United States)

    Anees, Amir; Hussain, Iqtadar; AlKhaldi, Ali Hussain; Aslam, Muhammad

    2018-06-01

    This paper presents a new linear optimization algorithm for power scheduling of electric appliances. The proposed system is applied in a smart home community, in which community controller acts as a virtual distribution company for the end consumers. We also present a pricing scheme between community controller and its residential users based on real-time pricing and likely block rates. The results of the proposed optimization algorithm demonstrate that by applying the anticipated technique, not only end users can minimise the consumption cost, but it can also reduce the power peak to an average ratio which will be beneficial for the utilities as well.

  13. Intermediate-Term Outcomes of Dual Adult versus Single-Kidney Transplantation: Evolution of a Surgical Technique

    Directory of Open Access Journals (Sweden)

    Ana K. Islam

    2016-01-01

    Full Text Available Background. Acceptance of dual kidney transplantation (DKT has proven difficult, due to surgical complexity and concerns regarding long-term outcomes. We herein present a standard technique for ipsilateral DKT and compare outcomes to single-kidney transplant (SKT recipients. Methods. A retrospective single-center comparison of DKT and SKT performed between February 2007 and July 2013. Results. Of 516 deceased donor kidney transplants, 29 were DKT and 487 were SKT. Mean follow-up was 43 ± 67 months. DKT recipients were older and more likely than SKT recipients to receive an extended criteria graft (p<0.001. For DKT versus SKT, the rates of delayed graft function (10.3 versus 9.2% and acute rejection (20.7 versus 22.4% were equivalent (p = ns. A higher than expected urologic complication rate in the DKT cohort (14 versus 2%, p<0.01 was reduced through modification of the ureteral anastomosis. Graft survival was equivalent between DKT and SKT groups (p = ns with actuarial 3-year DKT patient and graft survivals of 100% and 93%. At 3 years, the groups had similar renal function (p = ns. Conclusions. By utilizing extended criteria donor organs as DKT, the donor pool was enlarged while providing excellent patient and graft survival. The DKT urologic complication rate was reduced by modification of the ureteral anastomosis.

  14. Intermediate-Term Outcomes of Dual Adult versus Single-Kidney Transplantation: Evolution of a Surgical Technique.

    Science.gov (United States)

    Islam, Ana K; Knight, Richard J; Mayer, Wesley A; Hollander, Adam B; Patel, Samir; Teeter, Larry D; Graviss, Edward A; Saharia, Ashish; Podder, Hemangshu; Asham, Emad H; Gaber, A Osama

    2016-01-01

    Background. Acceptance of dual kidney transplantation (DKT) has proven difficult, due to surgical complexity and concerns regarding long-term outcomes. We herein present a standard technique for ipsilateral DKT and compare outcomes to single-kidney transplant (SKT) recipients. Methods. A retrospective single-center comparison of DKT and SKT performed between February 2007 and July 2013. Results. Of 516 deceased donor kidney transplants, 29 were DKT and 487 were SKT. Mean follow-up was 43 ± 67 months. DKT recipients were older and more likely than SKT recipients to receive an extended criteria graft (p DKT versus SKT, the rates of delayed graft function (10.3 versus 9.2%) and acute rejection (20.7 versus 22.4%) were equivalent (p = ns). A higher than expected urologic complication rate in the DKT cohort (14 versus 2%, p DKT and SKT groups (p = ns) with actuarial 3-year DKT patient and graft survivals of 100% and 93%. At 3 years, the groups had similar renal function (p = ns). Conclusions. By utilizing extended criteria donor organs as DKT, the donor pool was enlarged while providing excellent patient and graft survival. The DKT urologic complication rate was reduced by modification of the ureteral anastomosis.

  15. Management of Excessive Weight Loss Following Laparoscopic Roux-en-Y Gastric Bypass: Clinical Algorithm and Surgical Techniques.

    Science.gov (United States)

    Akusoba, Ikemefuna; Birriel, T Javier; El Chaar, Maher

    2016-01-01

    There are no clinical guidelines or published studies addressing excessive weight loss and protein calorie malnutrition following a standard Roux-en-Y gastric bypass (RYGB) to guide nutritional management and treatment strategies. This study demonstrates the presentation, clinical algorithm, surgical technique, and outcomes of patients afflicted and successfully treated with excessive weight loss following a standard RYGB. Three patients were successfully reversed to normal anatomy after evaluation, management, and treatment by multidisciplinary team. Lowest BMI (kg/m(2)) was 18.9, 17.9, and 14.2, respectively. Twelve-month post-operative BMI (kg/m(2)) was 28.9, 22.8, and 26.1, respectively. Lowest weight (lbs) was 117, 128, and 79, respectively. Twelve-month post-operative weight (lbs) was 179, 161, and 145, respectively. Pre-reversal gastrostomy tube was inserted into the remnant stomach to demonstrate weight gain and improve nutritional status prior to reversal to original anatomy. We propose a practical clinical algorithm for the work-up and management of patients with excessive weight loss and protein calorie malnutrition after standard RYGB including reversal to normal anatomy.

  16. Comparison of four surgical techniques for management of pseudophakic and aphakic retinal detachment: a multicenter clinical trial.

    Science.gov (United States)

    Moradian, Siamak; Ahmadieh, Hamid; Faghihi, Hooshang; Ramezani, Alireza; Entezari, Morteza; Banaee, Touka; Heidari, Ebadollah; Behboudi, Hassan; Yasseri, Mehdi

    2016-09-01

    To compare the visual and anatomical outcomes of four surgical techniques to manage pseudophakic and aphakic retinal detachment (PARD). In a multicenter randomized clinical trial, 211 eyes of 211 patients with PARD and proliferative vitreoretinopathy (PVR) grade B or less were randomly assigned to one of the four treatment groups: (1) scleral buckling (SB), 50 eyes, (2) vitrectomy without band, 51 eyes, (3) vitrectomy with encircling band (EB), 58 eyes, and (4) triamcinolone acetonide (TA) assisted vitrectomy, 52 eyes. Patients were followed for 12 months after the surgery. The best-corrected visual acuity (BCVA) and retinal reattachment rate at each follow-up time point were considered as the primary outcome measures. PVR, macular pucker, and cystoid macular edema were considered as the secondary outcomes. Visual improvement was achieved in all treatment groups relative to the baseline at all time points (all Ps  0.99). There were no statistically significant differences among the groups in terms of adverse events. SB, TA-assisted vitrectomy, and vitrectomy with and without buckle had comparable outcomes in the management of PARD.

  17. [Liver transplantation--indications, surgical technique, results--the analysis of a clinical series of 200 cases].

    Science.gov (United States)

    Popescu, I; Ionescu, M; Braşoveanu, V; Hrehoreţ, D; Matei, E; Dorobantu, B; Zamfir, R; Alexandrescu, S; Grigorie, M; Tulbure, D; Popa, L; Ungureanu, M; Tomescu, D; Droc, G; Popescu, H; Cristea, A; Gheorghe, L; Iacob, S; Gheorghe, C; Boroş, M; Lupescu, I; Vlad, L; Herlea, V; Croitoru, M; Platon, P; Alloub, A

    2010-01-01

    Initially considered experimental, liver transplantation (LT) has become the treatment of choice for the patients with end-stage liver diseases. Between April 2000 and October 2009, 200 LTs (10 reLTs) were performed in 190 patients, this study being retrospective. There were transplanted 110 men and 80 women, 159 adults and 31 children with the age between 1 and 64 years old (mean age--39.9). The main indication in the adult group was represented by viral cirrhosis, while the pediatric series the etiology was mainly glycogenosis and biliary atresia. There were performed 143 whole graft LTs, 46 living donor LTs, 6 split LTs, 4 reduced LTs and one domino LT RESULTS: The postoperative survival was 90% (170 patients). The patient and graft one-year and five-year survivals were 76.9%, 73.6% and 71%, 68.2%, respectively. The early complications occurred in 127 patients (67%). The late complications were recorded in 71 patients (37.3%). The intraoperative and early postoperative mortality rate was 9.5% (18 patients). The Romanian liver transplantation program from Fundeni includes all types of current surgical techniques and the results are comparable with those from other international centers.

  18. Influence of the surgical technique and surface roughness on the primary stability of an implant in artificial bone with a density equivalent to maxillary bone: a laboratory study.

    NARCIS (Netherlands)

    Tabassum, A.; Meijer, G.J.; Wolke, J.G.C.; Jansen, J.A.

    2009-01-01

    OBJECTIVE: The aim of this biomechanical study was to assess the effect of surgical technique and surface roughness on primary implant stability in low-density bone. MATERIAL AND METHODS: Eighty screw-shaped (Biocomp) implants with machined or etched surface topography were inserted into a

  19. Influence of surgical technique and surface roughness on the primary stability of an implant in artificial bone with different cortical thickness: a laboratory study.

    NARCIS (Netherlands)

    Tabassum, A.; Meijer, G.J.; Wolke, J.G.C.; Jansen, J.A.

    2010-01-01

    OBJECTIVE: The aim of this biomechanical study was to assess the interrelated effect of both surface roughness and surgical technique on the primary stability of dental implants. MATERIAL AND METHODS: For the experiment, 160 screw-designed implants (Biocomp), with either a machined or an etched

  20. Optimizing patient flow in a large hospital surgical centre by means of discrete-event computer simulation models.

    Science.gov (United States)

    Ferreira, Rodrigo B; Coelli, Fernando C; Pereira, Wagner C A; Almeida, Renan M V R

    2008-12-01

    This study used the discrete-events computer simulation methodology to model a large hospital surgical centre (SC), in order to analyse the impact of increases in the number of post-anaesthetic beds (PABs), of changes in surgical room scheduling strategies and of increases in surgery numbers. The used inputs were: number of surgeries per day, type of surgical room scheduling, anaesthesia and surgery duration, surgical teams' specialty and number of PABs, and the main outputs were: number of surgeries per day, surgical rooms' use rate and blocking rate, surgical teams' use rate, patients' blocking rate, surgery delays (minutes) and the occurrence of postponed surgeries. Two basic strategies were implemented: in the first strategy, the number of PABs was increased under two assumptions: (a) following the scheduling plan actually used by the hospital (the 'rigid' scheduling - surgical rooms were previously assigned and assignments could not be changed) and (b) following a 'flexible' scheduling (surgical rooms, when available, could be freely used by any surgical team). In the second, the same analysis was performed, increasing the number of patients (up to the system 'feasible maximum') but fixing the number of PABs, in order to evaluate the impact of the number of patients over surgery delays. It was observed that the introduction of a flexible scheduling/increase in PABs would lead to a significant improvement in the SC productivity.

  1. A Preconditioning Technique for First-Order Primal-Dual Splitting Method in Convex Optimization

    Directory of Open Access Journals (Sweden)

    Meng Wen

    2017-01-01

    Full Text Available We introduce a preconditioning technique for the first-order primal-dual splitting method. The primal-dual splitting method offers a very general framework for solving a large class of optimization problems arising in image processing. The key idea of the preconditioning technique is that the constant iterative parameters are updated self-adaptively in the iteration process. We also give a simple and easy way to choose the diagonal preconditioners while the convergence of the iterative algorithm is maintained. The efficiency of the proposed method is demonstrated on an image denoising problem. Numerical results show that the preconditioned iterative algorithm performs better than the original one.

  2. Artificial intelligence search techniques for optimization of the cold source geometry

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1988-01-01

    Most optimization studies of cold neutron sources have concentrated on the numerical prediction or experimental measurement of the cold moderator optimum thickness which produces the largest cold neutron leakage for a given thermal neutron source. Optimizing the geometrical shape of the cold source, however, is a more difficult problem because the optimized quantity, the cold neutron leakage, is an implicit function of the shape which is the unknown in such a study. We draw an analogy between this problem and a state space search, then we use a simple Artificial Intelligence (AI) search technique to determine the optimum cold source shape based on a two-group, r-z diffusion model. We implemented this AI design concept in the computer program AID which consists of two modules, a physical model module and a search module, which can be independently modified, improved, or made more sophisticated. 7 refs., 1 fig

  3. Artificial intelligence search techniques for the optimization of cold source geometry

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1988-01-01

    Most optimization studies of cold neutron sources have concentrated on the numerical prediction or experimental measurement of the cold moderator optimum thickness that produces the largest cold neutron leakage for a given thermal neutron source. Optimizing the geometric shape of the cold source, however, is a more difficult problem because the optimized quantity, the cold neutron leakage, is an implicit function of the shape, which is the unknown in such a study. An analogy is drawn between this problem and a state space search, then a simple artificial intelligence (AI) search technique is used to determine the optimum cold source shape based on a two-group, r-z diffusion model. This AI design concept was implemented in the computer program AID, which consists of two modules, a physical model module, and a search module, which can be independently modified, improved, or made more sophisticated

  4. Active load sharing technique for on-line efficiency optimization in DC microgrids

    DEFF Research Database (Denmark)

    Sanseverino, E. Riva; Zizzo, G.; Boscaino, V.

    2017-01-01

    Recently, DC power distribution is gaining more and more importance over its AC counterpart achieving increased efficiency, greater flexibility, reduced volumes and capital cost. In this paper, a 24-120-325V two-level DC distribution system for home appliances, each including three parallel DC......-DC converters, is modeled. An active load sharing technique is proposed for the on-line optimization of the global efficiency of the DC distribution network. The algorithm aims at the instantaneous efficiency optimization of the whole DC network, based on the on-line load current sampling. A Look Up Table......, is created to store the real efficiencies of the converters taking into account components tolerances. A MATLAB/Simulink model of the DC distribution network has been set up and a Genetic Algorithm has been employed for the global efficiency optimization. Simulation results are shown to validate the proposed...

  5. Optimization models and techniques for implementation and pricing of electricity markets

    International Nuclear Information System (INIS)

    Madrigal Martinez, M.

    2001-01-01

    The operation and planning of vertically integrated electric power systems can be optimized using models that simulate solutions to problems. As the electric power industry is going through a period of restructuring, there is a need for new optimization tools. This thesis describes the importance of optimization tools and presents techniques for implementing them. It also presents methods for pricing primary electricity markets. Three modeling groups are studied. The first considers a simplified continuous and discrete model for power pool auctions. The second considers the unit commitment problem, and the third makes use of a new type of linear network-constrained clearing system model for daily markets for power and spinning reserve. The newly proposed model considers bids for supply and demand and bilateral contracts. It is a direct current model for the transmission network

  6. Integration of artificial intelligence and numerical optimization techniques for the design of complex aerospace systems

    International Nuclear Information System (INIS)

    Tong, S.S.; Powell, D.; Goel, S.

    1992-02-01

    A new software system called Engineous combines artificial intelligence and numerical methods for the design and optimization of complex aerospace systems. Engineous combines the advanced computational techniques of genetic algorithms, expert systems, and object-oriented programming with the conventional methods of numerical optimization and simulated annealing to create a design optimization environment that can be applied to computational models in various disciplines. Engineous has produced designs with higher predicted performance gains that current manual design processes - on average a 10-to-1 reduction of turnaround time - and has yielded new insights into product design. It has been applied to the aerodynamic preliminary design of an aircraft engine turbine, concurrent aerodynamic and mechanical preliminary design of an aircraft engine turbine blade and disk, a space superconductor generator, a satellite power converter, and a nuclear-powered satellite reactor and shield. 23 refs

  7. A reduced scale two loop PWR core designed with particle swarm optimization technique

    International Nuclear Information System (INIS)

    Lima Junior, Carlos A. Souza; Pereira, Claudio M.N.A; Lapa, Celso M.F.; Cunha, Joao J.; Alvim, Antonio C.M.

    2007-01-01

    Reduced scale experiments are often employed in engineering projects because they are much cheaper than real scale testing. Unfortunately, designing reduced scale thermal-hydraulic circuit or equipment, with the capability of reproducing, both accurately and simultaneously, all physical phenomena that occur in real scale and at operating conditions, is a difficult task. To solve this problem, advanced optimization techniques, such as Genetic Algorithms, have been applied. Following this research line, we have performed investigations, using the Particle Swarm Optimization (PSO) Technique, to design a reduced scale two loop Pressurized Water Reactor (PWR) core, considering 100% of nominal power and non accidental operating conditions. Obtained results show that the proposed methodology is a promising approach for forced flow reduced scale experiments. (author)

  8. A Suboptimal PTS Algorithm Based on Particle Swarm Optimization Technique for PAPR Reduction in OFDM Systems

    Directory of Open Access Journals (Sweden)

    Ho-Lung Hung

    2008-08-01

    Full Text Available A suboptimal partial transmit sequence (PTS based on particle swarm optimization (PSO algorithm is presented for the low computation complexity and the reduction of the peak-to-average power ratio (PAPR of an orthogonal frequency division multiplexing (OFDM system. In general, PTS technique can improve the PAPR statistics of an OFDM system. However, it will come with an exhaustive search over all combinations of allowed phase weighting factors and the search complexity increasing exponentially with the number of subblocks. In this paper, we work around potentially computational intractability; the proposed PSO scheme exploits heuristics to search the optimal combination of phase factors with low complexity. Simulation results show that the new technique can effectively reduce the computation complexity and PAPR reduction.

  9. A Suboptimal PTS Algorithm Based on Particle Swarm Optimization Technique for PAPR Reduction in OFDM Systems

    Directory of Open Access Journals (Sweden)

    Lee Shu-Hong

    2008-01-01

    Full Text Available Abstract A suboptimal partial transmit sequence (PTS based on particle swarm optimization (PSO algorithm is presented for the low computation complexity and the reduction of the peak-to-average power ratio (PAPR of an orthogonal frequency division multiplexing (OFDM system. In general, PTS technique can improve the PAPR statistics of an OFDM system. However, it will come with an exhaustive search over all combinations of allowed phase weighting factors and the search complexity increasing exponentially with the number of subblocks. In this paper, we work around potentially computational intractability; the proposed PSO scheme exploits heuristics to search the optimal combination of phase factors with low complexity. Simulation results show that the new technique can effectively reduce the computation complexity and PAPR reduction.

  10. A Note on Using Partitioning Techniques for Solving Unconstrained Optimization Problems on Parallel Systems

    Directory of Open Access Journals (Sweden)

    Mehiddin Al-Baali

    2015-12-01

    Full Text Available We deal with the design of parallel algorithms by using variable partitioning techniques to solve nonlinear optimization problems. We propose an iterative solution method that is very efficient for separable functions, our scope being to discuss its performance for general functions. Experimental results on an illustrative example have suggested some useful modifications that, even though they improve the efficiency of our parallel method, leave some questions open for further investigation.

  11. Method and apparatus for optimizing operation of a power generating plant using artificial intelligence techniques

    Science.gov (United States)

    Wroblewski, David [Mentor, OH; Katrompas, Alexander M [Concord, OH; Parikh, Neel J [Richmond Heights, OH

    2009-09-01

    A method and apparatus for optimizing the operation of a power generating plant using artificial intelligence techniques. One or more decisions D are determined for at least one consecutive time increment, where at least one of the decisions D is associated with a discrete variable for the operation of a power plant device in the power generating plant. In an illustrated embodiment, the power plant device is a soot cleaning device associated with a boiler.

  12. Multiple sensitive estimation and optimal sample size allocation in the item sum technique.

    Science.gov (United States)

    Perri, Pier Francesco; Rueda García, María Del Mar; Cobo Rodríguez, Beatriz

    2018-01-01

    For surveys of sensitive issues in life sciences, statistical procedures can be used to reduce nonresponse and social desirability response bias. Both of these phenomena provoke nonsampling errors that are difficult to deal with and can seriously flaw the validity of the analyses. The item sum technique (IST) is a very recent indirect questioning method derived from the item count technique that seeks to procure more reliable responses on quantitative items than direct questioning while preserving respondents' anonymity. This article addresses two important questions concerning the IST: (i) its implementation when two or more sensitive variables are investigated and efficient estimates of their unknown population means are required; (ii) the determination of the optimal sample size to achieve minimum variance estimates. These aspects are of great relevance for survey practitioners engaged in sensitive research and, to the best of our knowledge, were not studied so far. In this article, theoretical results for multiple estimation and optimal allocation are obtained under a generic sampling design and then particularized to simple random sampling and stratified sampling designs. Theoretical considerations are integrated with a number of simulation studies based on data from two real surveys and conducted to ascertain the efficiency gain derived from optimal allocation in different situations. One of the surveys concerns cannabis consumption among university students. Our findings highlight some methodological advances that can be obtained in life sciences IST surveys when optimal allocation is achieved. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Search method optimization technique for thermal design of high power RFQ structure

    International Nuclear Information System (INIS)

    Sharma, N.K.; Joshi, S.C.

    2009-01-01

    RRCAT has taken up the development of 3 MeV RFQ structure for the low energy part of 100 MeV H - ion injector linac. RFQ is a precision machined resonating structure designed for high rf duty factor. RFQ structural stability during high rf power operation is an important design issue. The thermal analysis of RFQ has been performed using ANSYS finite element analysis software and optimization of various parameters is attempted using Search Method optimization technique. It is an effective optimization technique for the systems governed by a large number of independent variables. The method involves examining a number of combinations of values of independent variables and drawing conclusions from the magnitude of the objective function at these combinations. In these methods there is a continuous improvement in the objective function throughout the course of the search and hence these methods are very efficient. The method has been employed in optimization of various parameters (called independent variables) of RFQ like cooling water flow rate, cooling water inlet temperatures, cavity thickness etc. involved in RFQ thermal design. The temperature rise within RFQ structure is the objective function during the thermal design. Using ANSYS Programming Development Language (APDL), various multiple iterative programmes are written and the analysis are performed to minimize the objective function. The dependency of the objective function on various independent variables is established and the optimum values of the parameters are evaluated. The results of the analysis are presented in the paper. (author)

  14. An Adaptive Image Enhancement Technique by Combining Cuckoo Search and Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Zhiwei Ye

    2015-01-01

    Full Text Available Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper.

  15. An adaptive image enhancement technique by combining cuckoo search and particle swarm optimization algorithm.

    Science.gov (United States)

    Ye, Zhiwei; Wang, Mingwei; Hu, Zhengbing; Liu, Wei

    2015-01-01

    Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO) for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper.

  16. Combinatorial techniques to efficiently investigate and optimize organic thin film processing and properties.

    Science.gov (United States)

    Wieberger, Florian; Kolb, Tristan; Neuber, Christian; Ober, Christopher K; Schmidt, Hans-Werner

    2013-04-08

    In this article we present several developed and improved combinatorial techniques to optimize processing conditions and material properties of organic thin films. The combinatorial approach allows investigations of multi-variable dependencies and is the perfect tool to investigate organic thin films regarding their high performance purposes. In this context we develop and establish the reliable preparation of gradients of material composition, temperature, exposure, and immersion time. Furthermore we demonstrate the smart application of combinations of composition and processing gradients to create combinatorial libraries. First a binary combinatorial library is created by applying two gradients perpendicular to each other. A third gradient is carried out in very small areas and arranged matrix-like over the entire binary combinatorial library resulting in a ternary combinatorial library. Ternary combinatorial libraries allow identifying precise trends for the optimization of multi-variable dependent processes which is demonstrated on the lithographic patterning process. Here we verify conclusively the strong interaction and thus the interdependency of variables in the preparation and properties of complex organic thin film systems. The established gradient preparation techniques are not limited to lithographic patterning. It is possible to utilize and transfer the reported combinatorial techniques to other multi-variable dependent processes and to investigate and optimize thin film layers and devices for optical, electro-optical, and electronic applications.

  17. Combinatorial Techniques to Efficiently Investigate and Optimize Organic Thin Film Processing and Properties

    Directory of Open Access Journals (Sweden)

    Hans-Werner Schmidt

    2013-04-01

    Full Text Available In this article we present several developed and improved combinatorial techniques to optimize processing conditions and material properties of organic thin films. The combinatorial approach allows investigations of multi-variable dependencies and is the perfect tool to investigate organic thin films regarding their high performance purposes. In this context we develop and establish the reliable preparation of gradients of material composition, temperature, exposure, and immersion time. Furthermore we demonstrate the smart application of combinations of composition and processing gradients to create combinatorial libraries. First a binary combinatorial library is created by applying two gradients perpendicular to each other. A third gradient is carried out in very small areas and arranged matrix-like over the entire binary combinatorial library resulting in a ternary combinatorial library. Ternary combinatorial libraries allow identifying precise trends for the optimization of multi-variable dependent processes which is demonstrated on the lithographic patterning process. Here we verify conclusively the strong interaction and thus the interdependency of variables in the preparation and properties of complex organic thin film systems. The established gradient preparation techniques are not limited to lithographic patterning. It is possible to utilize and transfer the reported combinatorial techniques to other multi-variable dependent processes and to investigate and optimize thin film layers and devices for optical, electro-optical, and electronic applications.

  18. Heat generation during implant placement in low-density bone: effect of surgical technique, insertion torque and implant macro design.

    Science.gov (United States)

    Marković, Aleksa; Mišić, Tijana; Miličić, Biljana; Calvo-Guirado, Jose Luis; Aleksić, Zoran; Ðinić, Ana

    2013-07-01

    The study aimed to investigate the effect of surgical technique, implant macrodesign and insertion torque on bone temperature changes during implant placement. In the in vitro study, 144 self-tapping (blueSKY(®) 4 × 10 mm; Bredent) and 144 non-self-tapping (Standard implant(®) 4.1 × 10 mm; Straumann) were placed in osteotomies prepared in pig ribs by lateral bone condensing or bone drilling techniques. The maximum insertion torque values of 30, 35 and 40 Ncm were used. Real-time bone temperature measurement during implant placement was performed by three thermocouples positioned vertically, in tripod configuration around every osteotomy, at a distance of 5 mm from it and at depths of 1, 5 and 10 mm. Data were analysed using Kruskal-Wallis, Mann-Whitney U-tests and Regression analysis. Significant predictor of bone temperature at the osteotomy depth of 1 mm was insertion torque (P = 0.003) and at the depth of 10-mm implant macrodesign (P = 0.029), while no significant predictor at depth of 5 mm was identified (P > 0.05). Higher insertion torque values as well as non-self-tapping implant macrodesign were related to higher temperatures. Implant placement in sites prepared by bone drilling induced significantly higher temperature increase (P = 0.021) compared with bone condensing sites at the depth of 5 mm, while no significant difference was recorded at other depths. Compared with 30 Ncm, insertion torque values of 35 and 40 Ncm produced significantly higher temperature increase (P = 0.005; P = 0.003, respectively) at the depth of 1 mm. There was no significant difference in temperature change induced by 35 and 40 Ncm, neither by implant macrodesign at all investigated depths (P > 0.05). Placement of self-tapping implants with low insertion torque into sites prepared by lateral bone condensing technique might be advantageous in terms of thermal effect on bone. © 2012 John Wiley & Sons A/S.

  19. Surgical treatment of Chiari malformation: review and progress

    Directory of Open Access Journals (Sweden)

    ZHANG Yuan-zheng

    2012-08-01

    Full Text Available The surgical treatment of Chiari malformation (CM began in 1932. With the advance of medical technology, the surgical technique of CM is also in constant improvement. But due to its pathogenesis has not yet clear, there is no accepted optimal method, and different levels of the operation is still controversial. The author reviewed the concept, pathogenesis, diagnosis and surgical treatment of CM. The hot topics and new technological application were also reviewed in this article.

  20. Towards automating the discovery of certain innovative design principles through a clustering-based optimization technique

    Science.gov (United States)

    Bandaru, Sunith; Deb, Kalyanmoy

    2011-09-01

    In this article, a methodology is proposed for automatically extracting innovative design principles which make a system or process (subject to conflicting objectives) optimal using its Pareto-optimal dataset. Such 'higher knowledge' would not only help designers to execute the system better, but also enable them to predict how changes in one variable would affect other variables if the system has to retain its optimal behaviour. This in turn would help solve other similar systems with different parameter settings easily without the need to perform a fresh optimization task. The proposed methodology uses a clustering-based optimization technique and is capable of discovering hidden functional relationships between the variables, objective and constraint functions and any other function that the designer wishes to include as a 'basis function'. A number of engineering design problems are considered for which the mathematical structure of these explicit relationships exists and has been revealed by a previous study. A comparison with the multivariate adaptive regression splines (MARS) approach reveals the practicality of the proposed approach due to its ability to find meaningful design principles. The success of this procedure for automated innovization is highly encouraging and indicates its suitability for further development in tackling more complex design scenarios.

  1. Dynamic optimization of distributed biological systems using robust and efficient numerical techniques.

    Science.gov (United States)

    Vilas, Carlos; Balsa-Canto, Eva; García, Maria-Sonia G; Banga, Julio R; Alonso, Antonio A

    2012-07-02

    Systems biology allows the analysis of biological systems behavior under different conditions through in silico experimentation. The possibility of perturbing biological systems in different manners calls for the design of perturbations to achieve particular goals. Examples would include, the design of a chemical stimulation to maximize the amplitude of a given cellular signal or to achieve a desired pattern in pattern formation systems, etc. Such design problems can be mathematically formulated as dynamic optimization problems which are particularly challenging when the system is described by partial differential equations.This work addresses the numerical solution of such dynamic optimization problems for spatially distributed biological systems. The usual nonlinear and large scale nature of the mathematical models related to this class of systems and the presence of constraints on the optimization problems, impose a number of difficulties, such as the presence of suboptimal solutions, which call for robust and efficient numerical techniques. Here, the use of a control vector parameterization approach combined with efficient and robust hybrid global optimization methods and a reduced order model methodology is proposed. The capabilities of this strategy are illustrated considering the solution of a two challenging problems: bacterial chemotaxis and the FitzHugh-Nagumo model. In the process of chemotaxis the objective was to efficiently compute the time-varying optimal concentration of chemotractant in one of the spatial boundaries in order to achieve predefined cell distribution profiles. Results are in agreement with those previously published in the literature. The FitzHugh-Nagumo problem is also efficiently solved and it illustrates very well how dynamic optimization may be used to force a system to evolve from an undesired to a desired pattern with a reduced number of actuators. The presented methodology can be used for the efficient dynamic optimization of

  2. Improving Pre-Operative Flexion in Primary TKA: A Surgical Technique Emphasizing Knee Flexion with 5-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Edward McPherson

    2014-06-01

    Full Text Available This study prospectively reviews a consecutive series of 228 primary total knee arthroplasty (TKA procedures utilizing a technique to optimize knee flexion. The main features include: (1the use of a “patellar friendly” femoral component and reduced thickness patellar components, (2 patient individualized adjustment of the femoral component rotation set strictly to the anterior-posterior femoral axis, (3a rigorous flexion compartment debridement to remove non-essential posterior femoral bone with a Z-osteotome, and (4incorporation of a rapid recovery protocol with features to promote knee flexion. Results were categorized into three groups: low pre-op flexion (90 degrees and below, regular pre-op flexion (91-125 degrees, and high pre-op flexion (126 degrees and above. Average flexion in the low flexion group improved by 20 degrees at 6 weeks, 28 degrees at 3 months, 31 degrees at 1 year, and 30 degrees at 5 years. In the regular flexion group, average flexion improved by 2 degrees at 6 weeks, 10 degrees at 3 months, 12 degrees at 1 year, and 13 degrees at 5 years. Finally, in the high flexion group, average flexion decreased by 7 degrees at 6 weeks, regained preoperative levels at 3 months, and increased by 3 degrees at 1 year and 4 degrees at 5 years. In summary, a technique that emphasizes patellofemoral kinematics can consistently improve flexion in TKA in short and long-term follow-up.

  3. Commissioning of the laboratory of Atucha II NPP. Implementation and optimization of analytical techniques, quality aspects

    International Nuclear Information System (INIS)

    Schoenbrod, Betina; Quispe, Benjamin; Cattaneo, Alberto; Rodriguez, Ivanna; Chocron, Mauricio; Farias, Silvia

    2012-09-01

    Atucha II NPP is a Pressurized Vessel Heavy Water Reactor (PVHWR) of 740 MWe designed by SIEMENSKWU. After some years of delay, this NPP is in advanced construction state, being the beginning of commercial operation expected for 2013. Nucleoelectrica Argentina (N.A.S.A.) is the company in charge of the finalization of this project and the future operation of the plant. The Comision Nacional de Energia Atomica (C.N.E.A.) is the R and D nuclear institution in the country that, among many other topics, provides technical support to the stations. The Commissioning Chemistry Division of CNAII is in charge of the commissioning of the demineralization water plant and the organization of the chemical laboratory. The water plant started operating successfully in July 2010 and is providing the plant with nuclear grade purity water. Currently, in the conventional ('cold') laboratory several activities are taking place. On one hand, analytical techniques for the future operation of the plant are being tested and optimized. On the other hand, the laboratory is participating in the cleaning and conservation of the different components of the plant, providing technical support and the necessary analysis. To define the analytical techniques for the normal operation of the plant, the parameters to be measured and their range were established in the Chemistry Manual. The necessary equipment and reagents were bought. In this work, a summary of the analytical techniques that are being implemented and optimized is presented. Common anions (chloride, sulfate, fluoride, bromide and nitrate) are analyzed by ion chromatography. Cations, mainly sodium, are determined by absorption spectrometry. A UV-Vis spectrometer is used to determine silicates, iron, ammonia, DQO, total solids, true color and turbidity. TOC measurements are performed with a TOC analyzer. To optimize the methods, several parameters are evaluated: linearity, detection and quantification limits, precision and

  4. Determination of the optimal tolerance for MLC positioning in sliding window and VMAT techniques

    International Nuclear Information System (INIS)

    Hernandez, V.; Abella, R.; Calvo, J. F.; Jurado-Bruggemann, D.; Sancho, I.; Carrasco, P.

    2015-01-01

    Purpose: Several authors have recommended a 2 mm tolerance for multileaf collimator (MLC) positioning in sliding window treatments. In volumetric modulated arc therapy (VMAT) treatments, however, the optimal tolerance for MLC positioning remains unknown. In this paper, the authors present the results of a multicenter study to determine the optimal tolerance for both techniques. Methods: The procedure used is based on dynalog file analysis. The study was carried out using seven Varian linear accelerators from five different centers. Dynalogs were collected from over 100 000 clinical treatments and in-house software was used to compute the number of tolerance faults as a function of the user-defined tolerance. Thus, the optimal value for this tolerance, defined as the lowest achievable value, was investigated. Results: Dynalog files accurately predict the number of tolerance faults as a function of the tolerance value, especially for low fault incidences. All MLCs behaved similarly and the Millennium120 and the HD120 models yielded comparable results. In sliding window techniques, the number of beams with an incidence of hold-offs >1% rapidly decreases for a tolerance of 1.5 mm. In VMAT techniques, the number of tolerance faults sharply drops for tolerances around 2 mm. For a tolerance of 2.5 mm, less than 0.1% of the VMAT arcs presented tolerance faults. Conclusions: Dynalog analysis provides a feasible method for investigating the optimal tolerance for MLC positioning in dynamic fields. In sliding window treatments, the tolerance of 2 mm was found to be adequate, although it can be reduced to 1.5 mm. In VMAT treatments, the typically used 5 mm tolerance is excessively high. Instead, a tolerance of 2.5 mm is recommended

  5. Surgical treatment of choanal atresia with transnasal endoscopic approach with stentless single side-hinged flap technique: 5 year retrospective analysis

    Directory of Open Access Journals (Sweden)

    Carmelo Saraniti

    Full Text Available Abstract Introduction: Choanal atresia is a rare congenital malformation of the nasal cavity characterized by the complete obliteration of the posterior choanae. In 67% of cases choanal atresia is unilateral, affecting mainly (71% the right nasal cavity. In contrast to the unilateral form, bilateral choanal atresia is a life-threatening condition often associated with respiratory distress with feeding and intermittent cyanosis exacerbated by crying. Surgical treatment remains the only therapeutic option. Objective: To report our experience in the use of a transnasal endoscopic approach with stentless single side-hinged flap technique for the surgical management of choanal atresia. Methods: A 5 year retrospective analysis of surgical outcomes of 18 patients treated for choanal atresia with a transnasal technique employing a single side-hinged flap without stent placement. All subjects were assessed preoperatively with a nasal endoscopy and a Maxillofacial computed tomography scan. Results: Ten males and eight females with a mean age at the time of surgery of 20.05 ± 11.32 years, underwent surgery for choanal atresia. Fifteen subjects (83.33% had a bony while 3 (26.77% a mixed bony-membranous atretic plate. Two and sixteen cases suffered from bilateral and unilateral choanal atresia respectively. No intra- and/or early postoperative complications were observed. Between 2 and 3 months after surgery two cases (11.11% of partial restenosis were found. Only one of these presented a relapse of the nasal obstruction and was subsequently successfully repaired with a second endoscopic procedure. Conclusion: The surgical technique described follows the basic requirements of corrective surgery and allows good visualization, evaluation and treatment of the atretic plate and the posterior third of the septum, in order to create the new choanal opening. We believe that the use of a stent is not necessary, as recommended in case of other surgical techniques

  6. Constrained Optimization Based on Hybrid Evolutionary Algorithm and Adaptive Constraint-Handling Technique

    DEFF Research Database (Denmark)

    Wang, Yong; Cai, Zixing; Zhou, Yuren

    2009-01-01

    A novel approach to deal with numerical and engineering constrained optimization problems, which incorporates a hybrid evolutionary algorithm and an adaptive constraint-handling technique, is presented in this paper. The hybrid evolutionary algorithm simultaneously uses simplex crossover and two...... mutation operators to generate the offspring population. Additionally, the adaptive constraint-handling technique consists of three main situations. In detail, at each situation, one constraint-handling mechanism is designed based on current population state. Experiments on 13 benchmark test functions...... and four well-known constrained design problems verify the effectiveness and efficiency of the proposed method. The experimental results show that integrating the hybrid evolutionary algorithm with the adaptive constraint-handling technique is beneficial, and the proposed method achieves competitive...

  7. A novel technique for preventing skin pressure sores using a rubber tube during surgical treatment of mandibular condyle fractures.

    Science.gov (United States)

    Kawase-Koga, Yoko; Mori, Yoshiyuki; Hoshi, Kazuhito; Takato, Tsuyoshi

    2013-11-01

    Craniofacial surgery occasionally results in sores and necrosis of the facial skin because of pressure from surgical instruments. During surgical treatment of mandibular condylar process fractures, the main mandibular fragment is routinely retracted downward using a wire to achieve a satisfactory anatomic reduction. This procedure may injure the facial skin. This potential complication is easily overlooked by medical staff, but it is easily preventable. We herein describe a method of using a rubber tube to avoid causing pressure sores of the facial skin during surgical treatment of mandibular condylar process fractures.

  8. Optimizing charge breeding techniques for ISOL facilities in Europe: Conclusions from the EMILIE project

    Energy Technology Data Exchange (ETDEWEB)

    Delahaye, P., E-mail: delahaye@ganil.fr; Jardin, P.; Maunoury, L. [GANIL, CEA/DSM-CNRS/IN2P3, Blvd. Becquerel, BP 55027, 14076 Caen Cedex 05 (France); Galatà, A.; Patti, G. [INFN–Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro (Padova) (Italy); Angot, J.; Lamy, T.; Thuillier, T. [LPSC–Université Grenoble Alpes–CNRS/IN2P3, 53 rue des Martyrs, 38026 Grenoble Cedex (France); Cam, J. F.; Traykov, E.; Ban, G. [LPC Caen, 6 Blvd. Maréchal Juin, 14050 Caen Cedex (France); Celona, L. [INFN–Laboratori Nazionali del Sud, via S. Sofia 62, 95125 Catania (Italy); Choinski, J.; Gmaj, P. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5a, 02 093 Warsaw (Poland); Koivisto, H.; Kolhinen, V.; Tarvainen, O. [Department of Physics, University of Jyväskylä, PB 35 (YFL), 40351 Jyväskylä (Finland); Vondrasek, R. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439 (United States); Wenander, F. [ISOLDE, CERN, 1211 Geneva 23 (Switzerland)

    2016-02-15

    The present paper summarizes the results obtained from the past few years in the framework of the Enhanced Multi-Ionization of short-Lived Isotopes for Eurisol (EMILIE) project. The EMILIE project aims at improving the charge breeding techniques with both Electron Cyclotron Resonance Ion Sources (ECRIS) and Electron Beam Ion Sources (EBISs) for European Radioactive Ion Beam (RIB) facilities. Within EMILIE, an original technique for debunching the beam from EBIS charge breeders is being developed, for making an optimal use of the capabilities of CW post-accelerators of the future facilities. Such a debunching technique should eventually resolve duty cycle and time structure issues which presently complicate the data-acquisition of experiments. The results of the first tests of this technique are reported here. In comparison with charge breeding with an EBIS, the ECRIS technique had lower performance in efficiency and attainable charge state for metallic ion beams and also suffered from issues related to beam contamination. In recent years, improvements have been made which significantly reduce the differences between the two techniques, making ECRIS charge breeding more attractive especially for CW machines producing intense beams. Upgraded versions of the Phoenix charge breeder, originally developed by LPSC, will be used at SPES and GANIL/SPIRAL. These two charge breeders have benefited from studies undertaken within EMILIE, which are also briefly summarized here.

  9. The trans-frontal-sinus subcranial approach for removal of large olfactory groove meningiomas: surgical technique and comparison to other approaches.

    Science.gov (United States)

    Boari, Nicola; Gagliardi, Filippo; Roberti, Fabio; Barzaghi, Lina Raffaella; Caputy, Anthony J; Mortini, Pietro

    2013-05-01

    Several surgical approaches have been previously reported for the treatment of olfactory groove meningiomas (OGM).The trans-frontal-sinus subcranial approach (TFSSA) for the removal of large OGMs is described, comparing it with other reported approaches in terms of advantages and drawbacks. The TFSSA was performed on cadaveric specimens to illustrate the surgical technique. The surgical steps of the TFSSA and the related anatomical pictures are reported. The approach was adopted in a clinical setting; a case illustration is reported to demonstrate the feasibility of the described approach and to provide intraoperative pictures. The TFSSA represents a possible route to treat large OGMs. The subcranial approach provides early devascularization of the tumor, direct tumor access from the base without traction on the frontal lobes, good overview of dissection of the optic nerves and anterior cerebral arteries, and dural reconstruction with pedicled pericranial flap. Georg Thieme Verlag KG Stuttgart · New York.

  10. Treatment outcomes of the simple bone cyst: A comparative study of 2 surgical techniques using artificial bone substitutes.

    Science.gov (United States)

    Higuchi, Takashi; Yamamoto, Norio; Shirai, Toshiharu; Hayashi, Katsuhiro; Takeuchi, Akihiko; Kimura, Hiroaki; Miwa, Shinji; Abe, Kensaku; Taniguchi, Yuta; Tsuchiya, Hiroyuki

    2018-05-01

    Simple bone cysts (SBCs) are benign lesions of unknown etiology. Because of its high relapse rate, they occasionally need a long period of treatment and restriction of activities in children and adolescent. Although various treatment modalities with variable differing outcomes have been described in the literature, no consensus has been reached regarding the standard treatment. The purpose of this study was to evaluate the outcome of a minimally invasive technique that uses a ceramic hydroxyapatite cannulated pin (HA pin) for the treatment of SBCs.Between 1998 and 2015, we have treated 75 patients with SBCs either with continuous decompression by inserting HA pins after curettage and multiple drilling (group 1, n = 39 patients) or with calcium phosphate cement (CPC) filling after curettage (group 2, n = 36 patients). These patients were retrospectively analyzed for recurrence-free survival (RFS) and factors implicated in SBC recurrence.Seventy-five patients (50 man and 25 females) with a mean age of 17.5 ± 11.6 years and a histopathologically confirmed diagnosis of SBCs were included. The mean follow-up period was 33 ± 25.3 months. RFS were 88% at 1 year and 81% at 5 years. Residual or progressing cysts were observed in 12 patients after the surgery and 10 of them underwent additional surgery. Recurrence rate was significantly higher in patients under the age of 10 years (P = .01), in long bone cysts (P = .01), and in active phase cysts (P = .003) (log-rank test). Multivariate analysis results revealed that age less than 10 years was an independent risk factor of recurrence (P = .04). No significant difference in recurrence rate was observed between groups 1 and 2. However, the mean operating time was significantly shorter in group 1. (62.4 ± 25.6 vs 110.5 ± 48.4 minutes in group 2).Continuous decompression using HA pin is a less invasive surgical technique for the treatment of SBCs compared with CPC filling and has a

  11. Artificial intelligent techniques for optimizing water allocation in a reservoir watershed

    Science.gov (United States)

    Chang, Fi-John; Chang, Li-Chiu; Wang, Yu-Chung

    2014-05-01

    This study proposes a systematical water allocation scheme that integrates system analysis with artificial intelligence techniques for reservoir operation in consideration of the great uncertainty upon hydrometeorology for mitigating droughts impacts on public and irrigation sectors. The AI techniques mainly include a genetic algorithm and adaptive-network based fuzzy inference system (ANFIS). We first derive evaluation diagrams through systematic interactive evaluations on long-term hydrological data to provide a clear simulation perspective of all possible drought conditions tagged with their corresponding water shortages; then search the optimal reservoir operating histogram using genetic algorithm (GA) based on given demands and hydrological conditions that can be recognized as the optimal base of input-output training patterns for modelling; and finally build a suitable water allocation scheme through constructing an adaptive neuro-fuzzy inference system (ANFIS) model with a learning of the mechanism between designed inputs (water discount rates and hydrological conditions) and outputs (two scenarios: simulated and optimized water deficiency levels). The effectiveness of the proposed approach is tested on the operation of the Shihmen Reservoir in northern Taiwan for the first paddy crop in the study area to assess the water allocation mechanism during drought periods. We demonstrate that the proposed water allocation scheme significantly and substantially avails water managers of reliably determining a suitable discount rate on water supply for both irrigation and public sectors, and thus can reduce the drought risk and the compensation amount induced by making restrictions on agricultural use water.

  12. A review on optimization production and upgrading biogas through CO2 removal using various techniques.

    Science.gov (United States)

    Andriani, Dian; Wresta, Arini; Atmaja, Tinton Dwi; Saepudin, Aep

    2014-02-01

    Biogas from anaerobic digestion of organic materials is a renewable energy resource that consists mainly of CH4 and CO2. Trace components that are often present in biogas are water vapor, hydrogen sulfide, siloxanes, hydrocarbons, ammonia, oxygen, carbon monoxide, and nitrogen. Considering the biogas is a clean and renewable form of energy that could well substitute the conventional source of energy (fossil fuels), the optimization of this type of energy becomes substantial. Various optimization techniques in biogas production process had been developed, including pretreatment, biotechnological approaches, co-digestion as well as the use of serial digester. For some application, the certain purity degree of biogas is needed. The presence of CO2 and other trace components in biogas could affect engine performance adversely. Reducing CO2 content will significantly upgrade the quality of biogas and enhancing the calorific value. Upgrading is generally performed in order to meet the standards for use as vehicle fuel or for injection in the natural gas grid. Different methods for biogas upgrading are used. They differ in functioning, the necessary quality conditions of the incoming gas, and the efficiency. Biogas can be purified from CO2 using pressure swing adsorption, membrane separation, physical or chemical CO2 absorption. This paper reviews the various techniques, which could be used to optimize the biogas production as well as to upgrade the biogas quality.

  13. Pre-optimization of radiotherapy treatment planning: an artificial neural network classification aided technique

    International Nuclear Information System (INIS)

    Hosseini-Ashrafi, M.E.; Bagherebadian, H.; Yahaqi, E.

    1999-01-01

    A method has been developed which, by using the geometric information from treatment sample cases, selects from a given data set an initial treatment plan as a step for treatment plan optimization. The method uses an artificial neural network (ANN) classification technique to select a best matching plan from the 'optimized' ANN database. Separate back-propagation ANN classifiers were trained using 50, 60 and 77 examples for three groups of treatment case classes (up to 21 examples from each class were used). The performance of the classifiers in selecting the correct treatment class was tested using the leave-one-out method; the networks were optimized with respect their architecture. For the three groups used in this study, successful classification fractions of 0.83, 0.98 and 0.93 were achieved by the optimized ANN classifiers. The automated response of the ANN may be used to arrive at a pre-plan where many treatment parameters may be identified and therefore a significant reduction in the steps required to arrive at the optimum plan may be achieved. Treatment planning 'experience' and also results from lengthy calculations may be used for training the ANN. (author)

  14. A Survey on Optimal Signal Processing Techniques Applied to Improve the Performance of Mechanical Sensors in Automotive Applications

    Science.gov (United States)

    Hernandez, Wilmar

    2007-01-01

    In this paper a survey on recent applications of optimal signal processing techniques to improve the performance of mechanical sensors is made. Here, a comparison between classical filter